Solid-state cell and manufacturing method therefor, solid-state battery, and electric device

Abstract

The present application relates to a solid-state cell and a manufacturing method therefor, a solid-state battery, and an electric device. The solid-state cell comprises a solid electrolyte portion, and a positive electrode portion and a negative electrode portion which are separated by the solid electrolyte portion; any electrode portion independently comprises an electrode body and a tab portion connected to the electrode body; the electrode body comprises at least one electrode layer; and the electrode layer comprises a current collector layer and an electrode active material layer located on at least one side of the current collector layer. Two composite recesses used for accommodating positive and negative tab portions are formed on at least one side edge of the solid-state cell in the height direction thereof. Each electrode layer is provided with recesses corresponding to the two composite recesses. In the at least one electrode layer, the current collector layer is connected to a corresponding tab at the bottom of at least one recess; and the electrode layer further comprises a conductive adhesive layer located between the current collector layer and the electrode active material layer and at least covering a die-cut edge region of the tab recess.

Description

Solid-state battery cells and their preparation methods, solid-state batteries and electrical devices

[0001] Related applications

[0002] This application claims priority to Chinese patent application No. CN2024110450465, filed on July 31, 2024, entitled "Solid-state battery cell and method for preparation thereof, solid-state battery and power device", the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of solid-state battery technology, and further to solid-state cells and their preparation methods, solid-state batteries and electrical devices. Background Technology

[0004] The statements herein are provided only as background information in connection with this application and do not necessarily constitute prior art.

[0005] Solid-state batteries use a non-flammable solid electrolyte instead of the organic electrolyte in traditional liquid secondary batteries, significantly improving battery safety and are considered the next generation of batteries closest to industrialization. Further improvements in the energy density and cycle performance of solid-state batteries are crucial for advancing their industrialization. Summary of the Invention

[0006] According to various embodiments and examples of this application, this application provides a solid-state battery cell, a method for fabricating the same, a solid-state battery, and an electrical device. This solid-state battery cell can improve the energy density and cycle performance of solid-state batteries; furthermore, it can also improve the reliability of solid-state batteries.

[0007] In a first aspect of this application, a solid-state battery cell is provided, comprising a solid electrolyte portion and two electrode portions, one of which is a positive electrode portion and the other is a negative electrode portion, wherein the positive electrode portion and the negative electrode portion are isolated by the solid electrolyte portion; each of the electrode portions independently includes an electrode body and a tab portion connected to the electrode body, the electrode body including at least one electrode layer, the electrode layer including a current collector layer and an electrode active material layer located on at least one side of the current collector layer; the tab portion in the positive electrode portion is a positive tab portion, and the tab portion in the negative electrode portion is a negative tab portion;

[0008] The height direction of the solid-state battery cell is denoted as the Y direction, the width direction as the X direction, and the thickness direction as the Z direction; the X direction, the Y direction, and the Z direction are perpendicular to each other;

[0009] At at least one edge in the Y direction, the solid-state battery cell has two composite grooves, referred to as the first composite groove and the second composite groove, respectively; the first composite groove is used to accommodate at least a portion of the positive electrode tab, and the second composite groove is used to accommodate at least a portion of the negative electrode tab; each electrode layer has grooves corresponding to the first composite groove and the second composite groove, respectively.

[0010] In the at least one electrode layer, the current collector layer is connected to a tab at the bottom of at least one of the grooves, and the electrode layer further includes a conductive adhesive layer located between the current collector layer and the electrode active material layer, the conductive adhesive layer at least covering the die-cut edge region of the groove where the tab is located.

[0011] This solid-state battery cell features a first composite groove at the positive electrode tab, allowing it to bend inwards, and a second composite groove at the negative electrode tab, also allowing for inward bending. An active expansion region is formed in the area outside the first and second composite grooves along the width of the solid-state battery cell, at the same height. In other words, along the width of the solid-state battery cell, an active expansion region with the same height as the first and second composite grooves is provided in the space outside the positive and negative electrode tabs. This allows the solid-state battery cell to better utilize the space at the tabs, significantly increasing the volumetric energy density of the electrodes and thus improving the overall volumetric energy density of the solid-state battery. The two composite grooves also provide protection for the tabs, reducing the risk of tab breakage. Furthermore, a conductive adhesive layer is provided in the die-cut edge area of ​​the groove where the tab is located. On the one hand, the conductive adhesive layer can also provide good conductivity between the current collector layer and the electrode active material layer. In addition, the improved adhesion is beneficial to improving the cycle performance of the solid-state battery. On the other hand, it can improve the adhesion between the electrode active material layer and the current collector layer, which is conducive to forming a tab groove with neat edges when die-cutting the tab. It can reduce the shedding of electrode active material, which is beneficial to reducing the risk of internal short circuit and improving the reliability and production yield of the battery.

[0012] Furthermore, in one method for preparing this solid-state battery cell, when an electrode active material layer is introduced, the active pre-coating layer can also cover the tab groove area. The difference in adhesion between the active pre-coating layer and the current collector layer and the conductive adhesive layer can be used to more easily and selectively remove the electrode active material at the tab groove. This allows the electrode active material layer to form a neat edge contour during the die-cutting of the tab, reducing the shedding of electrode active material powder. This can improve the production yield of solid-state battery cells and solid-state batteries, and also improve the cycle performance of the prepared solid-state battery cells and solid-state batteries.

[0013] In some embodiments, the conductive adhesive layer at least covers the die-cut edge region of each groove in the electrode layer.

[0014] By ensuring that the conductive adhesive layer covers at least the die-cut edge area of ​​each groove in the electrode layer, the increased coverage area of ​​the conductive adhesive layer is more conducive to improving the adhesion and conductivity between the current collector layer and the electrode active material layer, which is beneficial to further improving the cycle performance of the solid-state battery. On the other hand, it can also improve the edge neatness of the electrode active material layer at each groove, reduce the shedding of electrode active material at each groove, which is more conducive to reducing the risk of internal short circuits and improving the reliability and production yield of the battery.

[0015] In some embodiments, the conductive adhesive layer at least covers the cut edge region of the electrode layer.

[0016] By ensuring that the conductive adhesive layer at least covers the cut edge area of ​​the electrode layer, it is more conducive to improving the adhesion and conductivity between the current collector layer and the electrode active material layer, which is beneficial to further improving the cycle performance of solid-state batteries. On the other hand, it can improve the edge neatness of the electrode active material layer at each cut position, further reduce the shedding of electrode active material, which is more conducive to reducing the risk of internal short circuits, and more conducive to improving the reliability and production yield of batteries.

[0017] In some embodiments, in the electrode layer including the conductive adhesive layer, the region between the electrode active material layer and the current collector layer includes a covered area provided with the conductive adhesive layer, and may or may not include a blank area where the conductive adhesive layer is not provided; the percentage of the area of ​​the covered area relative to the area of ​​the electrode active material layer is 64% to 100% when projected along the Z direction.

[0018] In some embodiments, in the electrode layer including the conductive adhesive layer, the projected area of ​​the conductive adhesive layer coincides with that of the electrode active material layer, measured along the Z direction.

[0019] Increasing the coverage area of ​​the conductive adhesive layer is more conducive to improving the adhesion and electronic conductivity between the current collector layer and the electrode active material layer, which is beneficial to further improving the cycle performance of solid-state batteries.

[0020] In some embodiments, the conductive adhesive layer includes an adhesive substrate and a conductive material.

[0021] In some embodiments, the electrode layer including the conductive adhesive layer satisfies one or more of the following characteristics:

[0022] The viscous matrix comprises a polyolefin resin; the polyolefin resin comprises one or more of the following polyolefin resins and polyolefin modified resins based on any of the following polyolefin resins: polyethylene, polypropylene, ethylene-vinyl acetate copolymer, styrene-butadiene copolymer, styrene-ethylene-butene-styrene block copolymer, styrene-isoprene-styrene block copolymer, and amorphous polyalphaolefin; the polyolefin modified resin is a copolymer of the polyolefin resin with maleic anhydride and petroleum resin;

[0023] The conductive material includes carbon conductive materials;

[0024] In the conductive adhesive layer, the mass ratio of the adhesive matrix to the conductive material is (0.6–1.5):1;

[0025] The resistivity of the electrode layer including the conductive adhesive layer is 10 Ω·m to 1000 Ω·m, and the adhesion between the current collector layer and the electrode active material layer in the electrode layer is 1 N / m to 50 N / m.

[0026] In some embodiments, the conductive adhesive layer satisfies one or more of the following characteristics:

[0027] The viscous matrix includes a polyolefin modified resin, which is a copolymer of the polyolefin resin, maleic anhydride, and petroleum resin in a mass ratio of 30:(2-5):(8-12).

[0028] The conductive material includes carbon conductive materials, which include one or more of the following: superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, carbon nanofibers, and mesophase carbon microspheres.

[0029] The sum of the masses of the adhesive matrix and the conductive material accounts for 90% to 98% of the mass of the conductive adhesive layer.

[0030] In the conductive adhesive layer, the mass ratio of the adhesive matrix to the conductive material is (0.8–1.4):1;

[0031] The resistivity of the electrode layer including the conductive adhesive layer is 10 Ω·m to 200 Ω·m, and the adhesion between the current collector layer and the electrode active material layer in the electrode layer is 3 N / m to 20 N / m.

[0032] By selecting the aforementioned conductive adhesive layer composition, it is beneficial to balance the adhesion and conductivity between the electrode active material layer and the current collector layer, which is beneficial to better improve the cycle performance of solid-state batteries, and also more beneficial to achieve a comprehensive improvement in the cycle performance, reliability and production yield of solid-state batteries.

[0033] In some embodiments, the electrode active material layer includes a conductive agent; and in the same electrode layer, taking one side of the current collector layer as a reference, the mass percentage of the conductive material in the conductive adhesive layer is higher than the mass percentage of the conductive agent in the electrode active material layer.

[0034] By controlling the content gradient of conductive material in the conductive adhesive layer and conductive agent in the electrode active material layer, it is more beneficial to improve the conductivity between the electrode active material layer and the current collector layer.

[0035] In some embodiments, the thickness of the conductive adhesive layer in the corresponding electrode layer is 0.5 μm to 3 μm, measured on one side of the current collector layer.

[0036] In some embodiments, the thickness of the conductive adhesive layer in the corresponding electrode layer, measured on one side of the current collector layer, is 0.5 μm to 1.5 μm.

[0037] By controlling the thickness of the conductive adhesive layer within the aforementioned range, it is beneficial to improve the adhesion and conductivity between the electrode active material layer and the current collector layer while also taking into account the high energy density advantage of solid-state cells.

[0038] In some embodiments, the active region in the solid-state cell located at the height of the first composite groove and the second composite groove is referred to as the cell active extension region;

[0039] The height of the electrode body at the active extension region of the battery cell is higher than the height of the electrode body at any composite groove.

[0040] In the aforementioned solid-state cell structure, the height of the positive electrode body at the active extension region of the cell is higher than the height of the positive electrode body at the first composite groove, and the height of the negative electrode body at the active extension region of the cell is higher than the height of the negative electrode body at the second composite groove. This allows the solid-state cell to make better use of the space at the tabs, thereby significantly increasing the space volume occupied by the electrode part in the solid-state cell and significantly improving the volumetric energy density of the solid-state cell and solid-state battery.

[0041] In some embodiments, the height of the solid-state cell in the Y direction is denoted as H0; the maximum height of the cell's active extension region in the Y direction is denoted as H. Δ The utilization rate ψ of the active extension region of the cell in the Y direction Y =H Δ / H0×100%;

[0042] Let W0 be the width of the solid-state battery cell in the X direction, and let W be the width of the active extension region of the battery cell in the X direction. Δ The utilization rate ψ of the active extension region of the cell in the X direction.X =W Δ / W0×100%;

[0043] Let A0 be the projected area of ​​the solid-state battery cell along the Z direction, and let A be the projected area of ​​the active extension region of the battery cell along the Z direction. Δ The two-dimensional utilization rate ψ of the active extended region of the battery cell A =A Δ / A0×100%;

[0044] The solid-state battery cell satisfies one or more of the following characteristics:

[0045] H Δ ≥0.05mm;

[0046] ψ Y ≥0.05%;

[0047] W Δ ≥50mm;

[0048] ψ X ≥60%;

[0049] ψ A ≥0.04%.

[0050] In some embodiments, the solid-state battery cell satisfies one or more of the following characteristics:

[0051] 0.05mm≤H Δ ≤1mm;

[0052] 0.1%≤ψ Y ≤2%;

[0053] 50mm≤W Δ ≤1000mm;

[0054] 60%≤ψ X ≤95%;

[0055] 0.04%≤ψ A ≤1.5%.

[0056] By adjusting the height parameter h of the active extension region of the battery cell Δ and utilization parameter ψ Y One or two of the aforementioned adjustments are beneficial for better utilizing the space in the height direction at the pole position.

[0057] By adjusting the width parameter w of the active extension region of the battery cell Δ and utilization parameter ψ X One or two of the aforementioned adjustments are beneficial for better utilizing the space in the width direction at the electrode position.

[0058] By increasing the two-dimensional utilization rate ψ of the cell's active extension region A Within the aforementioned range, regulation is conducive to better comprehensive utilization of the idle space at the electrode tab.

[0059] In some embodiments, the groove in the electrode layer where the tab is provided is referred to as the tab groove, and the extension height of any tab in the Y direction is greater than the height of the corresponding tab groove in the Y direction.

[0060] By reserving a certain extension height for the positive or negative tab, it is easy to use it as a soft tab to be transferred to a hard tab in subsequent processes.

[0061] In some embodiments, at least a portion of the tabs has a bent section within the corresponding groove.

[0062] At least a portion of the tab can be bent into the reserved groove, which helps to further increase the volume occupancy of the electrode part in the solid-state cell, and can significantly improve the volumetric energy density of the solid-state cell and solid-state battery.

[0063] In some embodiments, the width of the positive electrode tab in the X direction is smaller than the width of the first composite groove in the X direction; the width of the negative electrode tab in the X direction is smaller than the width of the second composite groove in the X direction.

[0064] In some embodiments, in the X direction, there is a gap between the positive electrode ear and the two side edges of the first composite groove, and a gap between the negative electrode ear and the two side edges of the second composite groove.

[0065] By leaving a certain gap on both sides of the corresponding electrode tab at the composite groove, a suitable space for movement can be reserved for the positive and negative electrode tabs, and it is also possible to bend the positive and negative electrode tabs into the composite groove more easily.

[0066] In some embodiments, the solid-state battery cell has a stacked structure.

[0067] In some embodiments, the positive electrode portion includes a positive electrode body and a positive electrode tab connected to the positive electrode body. The positive electrode body includes at least one positive electrode layer, which includes a positive electrode current collector layer and a positive electrode active material layer located on at least one side of the positive electrode current collector layer. Each positive electrode layer has a groove corresponding to the first composite groove and the second composite groove, respectively. In the at least one positive electrode layer, the positive electrode current collector layer is connected to the bottom of at least one of the grooves with a positive electrode tab. The positive electrode layer also includes a positive electrode conductive adhesive layer located between the positive electrode current collector layer and the positive electrode active material layer. The positive electrode conductive adhesive layer at least covers the die-cut edge region of the groove where the positive electrode tab is located. All the positive electrode tabs connected to the positive electrode body together constitute at least a portion of the positive electrode tab portion.

[0068] The negative electrode portion includes a negative electrode body and a negative electrode tab connected to the negative electrode body. The negative electrode body includes at least one negative electrode layer, which includes a negative electrode current collector layer and a negative electrode active material layer located on at least one side of the negative electrode current collector layer. Each negative electrode layer has a groove corresponding to the first composite groove and the second composite groove, respectively. In the at least one negative electrode layer, the negative electrode current collector layer is connected to the bottom of at least one of the grooves with a negative electrode tab. The negative electrode layer also includes a negative electrode conductive adhesive layer located between the negative electrode current collector layer and the negative electrode active material layer. The negative electrode conductive adhesive layer at least covers the die-cut edge area of ​​the groove where the negative electrode tab is located. All the negative electrode tabs connected to the negative electrode body together constitute at least a part of the negative electrode tab portion.

[0069] The solid electrolyte section includes at least one solid electrolyte layer, and any adjacent positive electrode layer and negative electrode layer are isolated by the solid electrolyte layer; each solid electrolyte layer is provided with an empty groove corresponding to the first composite groove and the second composite groove respectively.

[0070] When a solid-state battery cell adopts the aforementioned stacked structure, at the first composite groove, the positive electrode tab groove on the positive electrode layer, the empty groove on the negative electrode layer, and the empty groove on the solid electrolyte layer can be combined to form a concave space that allows the positive electrode tab to bend inward; at the second composite groove, the negative electrode tab groove on the negative electrode layer, the empty groove on the positive electrode layer, and the empty groove on the solid electrolyte layer can be combined to form a concave space that allows the negative electrode tab to bend inward. This significantly expands the active area of ​​the solid-state battery cell, allowing it to better utilize the space at the tabs, greatly increasing the volume occupied by the electrodes in the solid-state battery cell, and significantly improving the volumetric energy density of the solid-state battery cell and the solid-state battery. The two composite grooves also provide protection for the tabs, reducing the risk of tab breakage. Furthermore, a conductive adhesive layer is provided in the die-cut edge area of ​​the groove where the tab is located. On the one hand, the conductive adhesive layer can also provide good conductivity between the current collector layer and the electrode active material layer. In addition, the improved adhesion is beneficial to improving the cycle performance of the solid-state battery. On the other hand, it can improve the adhesion between the electrode active material layer and the current collector layer, which is conducive to forming a tab groove with neat edges when die-cutting the tab. It can reduce the shedding of electrode active material, which is beneficial to reducing the risk of internal short circuit and improving the reliability and production yield of the battery.

[0071] Furthermore, in one method for preparing this solid-state battery cell, when an electrode active material layer is introduced, the active pre-coating layer can also cover the tab groove area. The difference in adhesion between the active pre-coating layer and the current collector layer and the conductive adhesive layer can be used to more easily and selectively remove the electrode active material at the tab groove. This allows the electrode active material layer to form a neat edge contour during the die-cutting of the tab, reducing the shedding of electrode active material powder. This can improve the production yield of solid-state battery cells and solid-state batteries, and also improve the cycle performance of the prepared solid-state battery cells and solid-state batteries.

[0072] In some embodiments, the positive electrode body has multiple positive electrode layers; the negative electrode body has a number of negative electrode layers that matches the number of positive electrode layers in the positive electrode body.

[0073] When the number of positive electrode layers in the positive electrode body is multi-layered and the number of negative electrode layers in the negative electrode body is a matching multi-layered structure, the stacked structure corresponds to a multi-layered stacked structure. In this case, by utilizing the aforementioned cell active extension region structure design, it is beneficial to gain more volumetric energy density in the tab space.

[0074] In some embodiments, a plurality of positive electrode layers in the positive electrode body are connected to the positive electrode tabs; and a plurality of negative electrode layers in the negative electrode body are connected to the negative electrode tabs.

[0075] When multiple positive electrode layers in the positive electrode body are connected to positive electrode tabs and multiple negative electrode layers in the negative electrode body are connected to negative electrode tabs, it is more conducive to saving the waste of internal space caused by the stacking of multiple electrode tabs.

[0076] In a second aspect of this application, a method for preparing a solid-state battery cell is provided, comprising the following steps:

[0077] Prepare a required number of positive electrode sheets, each positive electrode sheet comprising a positive current collector layer and a positive active material layer located on at least one side of the positive current collector layer; at at least one edge in the height direction of the positive electrode sheet, the positive electrode sheet is provided with a positive tab groove and a first empty groove; at least one of the positive electrode sheets further comprises a positive tab connected to the positive current collector layer and a conductive adhesive layer located between the positive current collector layer and the positive active material layer, the conductive adhesive layer being referred to as the positive conductive adhesive layer, the positive tab being connected to the bottom of the positive tab groove of the corresponding positive electrode sheet, the positive conductive adhesive layer at least covering the die-cut edge area of ​​the positive tab groove;

[0078] Prepare a required number of negative electrode sheets, each negative electrode sheet comprising a negative electrode current collector layer and a negative electrode active material layer located on at least one side of the negative electrode current collector layer; at at least one edge in the height direction of the negative electrode sheet, the negative electrode sheet is provided with a negative electrode tab groove and a second empty groove; at least one of the negative electrode sheets further comprises a negative electrode tab connected to the negative electrode current collector layer and a conductive adhesive layer located between the negative electrode current collector layer and the negative electrode active material layer, the conductive adhesive layer being referred to as the negative electrode conductive adhesive layer, the negative electrode tab being connected to the bottom of the negative electrode tab groove of the corresponding negative electrode sheet, the negative electrode conductive adhesive layer at least covering the die-cut edge area of ​​the negative electrode tab groove;

[0079] Prepare the specified number of solid electrolyte membranes, wherein the solid electrolyte membranes are provided with a fourth cavity and a third cavity;

[0080] The positive electrode, the solid electrolyte membrane, and the negative electrode are stacked in the required quantities, with the positive and negative electrode separated by the solid electrolyte membrane. The outlines of the positive electrode tab groove, the fourth empty groove, and the second empty groove are aligned to form a first composite groove, and the outlines of the negative electrode tab groove, the third empty groove, and the first empty groove are aligned to form a second composite groove, thus obtaining a laminated component. Each positive electrode constitutes a positive electrode portion, each negative electrode constitutes a negative electrode portion, and each solid electrolyte membrane constitutes a solid electrolyte portion. Each positive electrode tab of the positive electrode portion constitutes a positive electrode tab soft segment, and at least a portion of the positive electrode tab soft segment is accommodated within the first composite groove. Each negative electrode tab of the negative electrode portion constitutes a negative electrode tab soft segment, and at least a portion of the negative electrode tab soft segment is accommodated within the second composite groove.

[0081] The laminated components are rolled to form the solid-state battery cell.

[0082] By assembling a positive electrode plate with the positive tab embedded in the positive tab groove, a negative electrode plate with the negative tab embedded in the negative tab groove, and a solid electrolyte membrane with corresponding empty grooves, the space utilization rate of solid-state battery cells can be greatly improved, and the volumetric energy density of solid-state battery cells can be significantly increased. Furthermore, by providing a positive conductive adhesive layer that covers at least the die-cut edge area of ​​the positive electrode tab groove between the positive active material layer and the positive current collector layer, the adhesion and conductivity between the positive active material layer and the positive current collector layer can be improved. This facilitates the formation of a neatly edged positive electrode tab groove during die-cutting and reduces the shedding of positive active material powder. Similarly, by providing a negative conductive adhesive layer that covers at least the die-cut edge area of ​​the negative electrode tab groove between the negative active material layer and the negative current collector layer, the adhesion and conductivity between the negative active material layer and the negative current collector layer can be improved. This is beneficial for improving the cycle performance of solid-state batteries and also facilitates the formation of a neatly edged negative electrode tab groove during die-cutting, reducing the shedding of negative active material powder. The provision of both positive and negative conductive adhesive layers helps reduce the risk of internal short circuits, thereby improving battery reliability and production yield.

[0083] In some embodiments, the positive electrode sheet including the positive tab is prepared by a method comprising the following steps:

[0084] On the surface of the positive electrode current collector membrane, a positive electrode body region and a positive electrode inactive region adjacent to each other are identified by a first boundary line. The first boundary line extends along the width direction of the positive electrode current collector membrane in a concave shape, such that the positive electrode inactive region includes a positive electrode tab concave region and a first concave region concave towards the positive electrode body region, and the positive electrode tab concave region and the first concave region are separated by the positive electrode body region; wherein, the positive electrode tab concave region is matched with the position of the positive electrode tab groove, and the first concave region is matched with the position of the first empty groove;

[0085] On at least one side surface of the positive electrode current collector film, the positive electrode conductive adhesive layer is applied to at least a portion of the positive electrode body region with the first dividing line as the coating boundary.

[0086] On at least one side surface of the positive electrode current collector membrane to which the positive electrode conductive adhesive layer is attached, a positive electrode active pre-coating layer is applied so that the positive electrode active pre-coating layer covers the positive electrode body region, the positive electrode tab recess region and the first recess region.

[0087] Remove the portion of the positive electrode active pre-coating that covers the concave area of ​​the positive electrode tab and the first concave area, exposing the corresponding positive electrode current collector film surface, to obtain a positive electrode die slice; wherein, the remaining portion of the positive electrode active pre-coating corresponds to the positive electrode active material layer, and the portion of the positive electrode current collector film covered by the positive electrode active material layer corresponds to the positive electrode current collector layer;

[0088] The positive electrode sheet is die-cut according to the first dividing line to form the positive electrode plate; wherein, the die-cutting process of the positive electrode sheet according to the first dividing line includes: die-cutting out the corresponding contour of the positive active material layer except for the concave area of ​​the positive electrode tab, die-cutting out the contour of the two side edges of the positive electrode tab groove and the positive electrode tab connected to the positive current collector layer in the concave area of ​​the positive electrode tab, and die-cutting out the first empty groove in the first concave area according to the first dividing line.

[0089] In the process of preparing the aforementioned positive electrode sheet including the positive electrode tab, before coating the positive active pre-coating layer, a conductive adhesive layer with a concave region is provided on the positive current collector film. On the one hand, this can improve the adhesion and conductivity between the positive active material layer and the positive current collector film. On the other hand, when the positive active material layer is introduced, the positive active pre-coating layer can cover the concave region as well. The difference in adhesion between the positive active pre-coating layer and the positive current collector film and the conductive adhesive layer can be used to more easily and selectively remove the positive active material in the concave region, thereby exposing the surface of the positive current collector film at the corresponding position. Then, the positive electrode tab can be die-cut in the concave region. The conductive adhesive layer can improve the adhesion and conductivity between the positive active material layer and the positive current collector film. When die-cutting the positive electrode tab, it is beneficial to form a neat edge contour, which can reduce the shedding of positive active material powder, thereby improving the production yield of solid-state cells and solid-state batteries, and also improving the cycle performance of the prepared solid-state cells and solid-state batteries. In the prepared positive electrode sheet, the positive tab can be bent inward into the positive tab groove, thereby increasing the space occupancy of the positive active material layer and improving the volumetric energy density of the solid-state cell and solid-state battery. Furthermore, the positive tab groove also provides protection for the positive tab, reducing the risk of tab breakage.

[0090] In some embodiments, the negative electrode sheet including the negative electrode tab is prepared by a method comprising the following steps:

[0091] On the surface of the negative electrode current collector membrane, a negative electrode body region and a negative electrode inactive region adjacent to each other are identified by a second boundary line. The second boundary line extends along the width direction of the negative electrode current collector membrane in a concave shape, such that the negative electrode inactive region includes a negative electrode tab concave region and a second concave region concave towards the negative electrode body region, and the negative electrode tab concave region and the second concave region are separated by the negative electrode body region; wherein, the negative electrode tab concave region is matched with the negative electrode tab groove, and the second concave region is matched with the second empty groove.

[0092] On at least one side surface of the negative electrode current collector film, the negative electrode conductive adhesive layer is applied to at least a portion of the negative electrode body region with the second dividing line as the coating boundary.

[0093] On at least one side surface of the negative electrode current collector film to which the negative electrode conductive adhesive layer is attached, an additional negative electrode active pre-coating layer is applied so that the negative electrode active pre-coating layer covers the negative electrode body region, the negative electrode tab recess region, and the second recess region.

[0094] Remove the portion of the negative electrode active pre-coating layer covering the negative electrode tab recess and the second recess, exposing the corresponding negative electrode current collector film surface to obtain a negative electrode die slice; wherein, the remaining portion of the negative electrode active pre-coating layer corresponds to the negative electrode active material layer, and the portion of the negative electrode current collector film covered by the negative electrode active material layer corresponds to the negative electrode current collector layer;

[0095] The negative electrode sheet is die-cut according to the second dividing line to form the negative electrode sheet; wherein, the die-cutting process of the negative electrode sheet according to the second dividing line includes: die-cutting out the corresponding contour of the area of ​​the negative electrode active material layer other than the negative electrode tab concave area, die-cutting out the contour of the two side edges of the negative electrode tab groove and the negative electrode tab connected to the negative electrode current collector layer in the negative electrode tab concave area, and die-cutting out the second empty groove in the second concave area according to the second dividing line.

[0096] In the process of preparing the aforementioned negative electrode sheet including the negative electrode tab, before coating the negative active pre-coating layer, a conductive adhesive layer with a concave region is provided on the negative current collector film. On the one hand, this can improve the adhesion and conductivity between the negative active material layer and the negative current collector film. On the other hand, when the negative active material layer is introduced, the negative active pre-coating layer can cover the concave region as well. The difference in adhesion between the negative active pre-coating layer and the negative current collector film and the conductive adhesive layer can be used to more easily and selectively remove the negative active material in the concave region, thereby exposing the surface of the negative current collector film at the corresponding position. Then, the negative electrode tab can be die-cut in the concave region. The conductive adhesive layer can improve the adhesion and conductivity between the negative active material layer and the negative current collector film. When die-cutting the negative electrode tab, it is beneficial to form a neat edge contour, which can reduce the shedding of negative active material powder. This can improve the production yield of solid-state cells and solid-state batteries, and also improve the cycle performance of the prepared solid-state cells and solid-state batteries. In the prepared negative electrode sheet, the negative electrode tab can be bent inward into the negative electrode tab groove, thereby increasing the space occupancy of the negative electrode active material layer and improving the volumetric energy density of the solid-state cell and solid-state battery. Furthermore, the negative electrode tab groove also provides protection for the negative electrode tab, reducing the risk of tab breakage.

[0097] In some embodiments, the method for preparing the solid-state battery cell satisfies one or more of the following characteristics:

[0098] During the preparation of the positive electrode sheet including the positive tab, the positive electrode conductive adhesive layer is coated on at least one side surface of the positive electrode current collector film, with the first dividing line as the coating boundary, over the entire area of ​​the positive electrode body region.

[0099] In the process of preparing the negative electrode sheet including the negative electrode tab, the negative electrode conductive adhesive layer is coated on at least one side surface of the negative electrode current collector film, with the second dividing line as the coating boundary, over the entire area of ​​the negative electrode body region.

[0100] Increasing the coverage area of ​​the conductive adhesive layer is also more conducive to improving the adhesion and conductivity between the current collector layer and the electrode active material layer, which is beneficial to further improving the cycle performance of solid-state batteries.

[0101] In some embodiments, the method for preparing the solid-state battery cell satisfies one or more of the following characteristics:

[0102] In the positive electrode sheet including the positive tab, in the height direction of the positive electrode sheet, the extension height of the positive tab in the positive electrode sheet is greater than the height of the corresponding positive tab groove in the positive electrode sheet;

[0103] In the negative electrode sheet including the negative electrode tab, in the height direction of the negative electrode sheet, the extension height of the negative electrode tab in the negative electrode sheet is greater than the height of the corresponding negative electrode tab groove in the negative electrode sheet.

[0104] By reserving a certain extension height for the positive or negative tab, it is easy to use it as a soft tab to be transferred to a hard tab in subsequent processes.

[0105] In some embodiments, the method for preparing the solid-state battery cell satisfies one or more of the following characteristics:

[0106] In the prepared solid-state battery cell, at least a portion of the positive electrode tab has a bent section within the first composite groove;

[0107] In the prepared solid-state battery cell, at least a portion of the negative electrode tab has a bent section within the second composite groove.

[0108] At least a portion of the tab can be bent into the corresponding composite groove, which can significantly improve the volumetric energy density of solid-state cells and solid-state batteries.

[0109] In some embodiments, the method for preparing the solid-state battery cell satisfies one or more of the following characteristics:

[0110] In the positive electrode sheet including the positive electrode tab, the width of the positive electrode tab is smaller than the width of the corresponding positive electrode tab groove in the width direction of the positive electrode sheet;

[0111] In the negative electrode sheet including the negative electrode tab, the width of the negative electrode tab is smaller than the width of the corresponding negative electrode tab groove in the width direction of the negative electrode sheet.

[0112] In some embodiments, the method for preparing the solid-state battery cell satisfies one or more of the following characteristics:

[0113] In the positive electrode sheet including the positive electrode tab, there is a gap between the positive electrode tab and the two side edges of the positive electrode tab groove in the width direction of the positive electrode sheet;

[0114] In the negative electrode sheet including the negative electrode tab, there is a gap between the negative electrode tab and the two side edges of the negative electrode tab groove in the width direction of the negative electrode sheet.

[0115] By leaving a certain gap on both sides of the corresponding electrode at the electrode groove, a suitable space for movement can be reserved for the positive and negative electrodes, and it also allows the positive and negative electrodes to be bent into the corresponding composite groove more easily.

[0116] In some implementations, the required number of positive electrode sheets is multiple; the required number of negative electrode sheets matches the required number of positive electrode sheets.

[0117] When there are multiple positive electrode plates used in assembling solid-state cells, there are correspondingly multiple negative electrode plates. At this time, the stacked structure corresponds to a multi-layer stacked structure. By utilizing the aforementioned cell active extension region structure design, it is beneficial to gain more volumetric energy density in the tab space.

[0118] In some embodiments, the plurality of positive electrode plates include the positive electrode tab; the plurality of negative electrode plates include the negative electrode tab.

[0119] When multiple positive electrode plates include positive tabs and multiple negative electrode plates include negative tabs, it is more beneficial to save the waste of internal space caused by the stacking of multiple tabs.

[0120] In some embodiments, the solid-state battery cell prepared is the solid-state battery cell described in the first aspect of this application.

[0121] In a third aspect of this application, a solid-state battery is provided, comprising at least one of the solid-state cells described in the first aspect of this application and solid-state cells prepared by the method for preparing solid-state cells described in the second aspect of this application.

[0122] In some embodiments, the solid-state battery is an all-solid-state battery.

[0123] Solid-state batteries, including the aforementioned solid-state cells, increase the volume of the electrode body at the tab height, thereby improving the space occupancy of the electrode active material layer and significantly increasing the volumetric energy density. Furthermore, the conductive adhesive layer enhances the adhesion and conductivity between the electrode active material layer and the current collector layer, facilitating the formation of neatly edged tab grooves during die-cutting. This reduces powder shedding from the electrode active material, improves the cycle performance of the solid-state battery, and also helps reduce the risk of internal short circuits, thus improving battery reliability and production yield.

[0124] In a fourth aspect of this application, an electrical device is provided, comprising at least one of the solid-state battery cell described in the first aspect of this application, a solid-state battery cell prepared by the method for preparing a solid-state battery cell described in the second aspect of this application, and a solid-state battery described in the third aspect of this application.

[0125] Details of one or more embodiments or examples of this application are set forth in the following drawings and description. Other features, objects, and advantages of this application will become apparent from the specification, drawings, and claims. Attached Figure Description

[0126] To better describe and illustrate the embodiments, examples, or models provided in this application, reference may be made to one or more accompanying drawings. Additional details or examples used to describe the drawings should not be considered as limiting the scope of any of the disclosed applications, the currently described embodiments, examples, or models, or the best mode of these applications as currently understood. Furthermore, the same reference numerals denote the same parts throughout the drawings. It should also be noted that the drawings are drawn in a simplified form and are only intended to facilitate and clarify the illustration of this application. The various dimensions of each part shown in the drawings are arbitrarily shown and may be precise or not drawn to scale. For example, the dimensions of parts are appropriately exaggerated in some places in the drawings to make the illustration clearer. Unless otherwise specified, the parts in the drawings are not drawn to scale. This application does not limit every dimension of every part.

[0127] In the attached diagram:

[0128] Figure 1 is a schematic diagram of the structure of a solid-state battery cell in one embodiment of this application; wherein (a) is the main view, (AA), (BB) and (CC) are cross-sectional views of the positions of AA, BB and CC respectively; the dashed lines are reference lines.

[0129] Figure 2 is a schematic diagram of the preparation process of the positive electrode and the negative electrode in one embodiment of this application; wherein, (a) from left to right corresponds to the four structures involved in the preparation process of the positive electrode, namely, the positive current collector film, the multilayer structure formed by stacking a positive conductive adhesive layer on the surface of the positive current collector film, the multilayer structure formed by continuing to coat the positive active pre-coating layer, and the positive electrode sheet including the positive electrode tab formed by die cutting; (b) from left to right corresponds to the four structures involved in the preparation process of the negative electrode, namely, the negative current collector film, the multilayer structure formed by stacking a negative conductive adhesive layer on the surface of the negative current collector film, the multilayer structure formed by continuing to coat the negative active pre-coating layer, and the negative electrode sheet including the negative electrode tab formed by die cutting.

[0130] Figure 3 is a schematic diagram of the structure of the positive electrode sheet in one embodiment of this application; where (a) is the front view and (DD) is the cross-sectional view at the DD position.

[0131] Figure 4 is a schematic diagram of the negative electrode sheet in one embodiment of this application; where (a) is the front view and (EE) is a cross-sectional view at the EE position.

[0132] Figure 5 is a schematic diagram of a solid-state battery cell according to an embodiment of this application.

[0133] Figure 6 is an exploded view of a solid-state battery cell according to an embodiment of this application, as shown in Figure 5.

[0134] Figure 7 is a schematic diagram of a battery module according to one embodiment of this application.

[0135] Figure 8 is a schematic diagram of a battery pack according to one embodiment of this application.

[0136] Figure 9 is an exploded view of the battery pack of one embodiment of this application shown in Figure 8.

[0137] Figure 10 is a schematic diagram of an electrical device using a solid-state battery as a power source according to an embodiment of this application.

[0138] Explanation of reference numerals in the attached figures: 10, positive electrode layer; 20, solid electrolyte layer; 30, negative electrode layer; 1300, positive electrode tab; 1302, first composite groove; 3300, negative electrode tab; 3302, second composite groove; X, X direction; Y, Y direction; Z, Z direction; 100, positive electrode sheet; 111, positive electrode current collector film; 1000, first boundary line; 1112, positive electrode body region; 1110, positive electrode inactive region; 1220, positive electrode tab recessed region; 1240, first recessed region; 120, positive electrode conductive adhesive layer; 1402, positive electrode active pre-coating layer; 110, positive electrode current collector layer; 140, positive electrode active material layer; 130, positive electrode tab; 122, positive electrode tab. 1. Groove; 124. First empty groove; 300. Negative electrode sheet; 311. Negative electrode current collector film; 3000. Second dividing line; 3112. Negative electrode body area; 3110. Negative electrode inactive area; 3220. Negative electrode tab recessed area; 3240. Second recessed area; 320. Negative electrode conductive adhesive layer; 3402. Negative electrode active pre-coating layer; 310. Negative electrode current collector layer; 340. Negative electrode active material layer; 330. Negative electrode tab; 322. Negative electrode tab groove; 324. Second empty groove; 1. Battery pack; 2. Upper casing; 3. Lower casing; 4. Battery module; 5. Solid-state battery cell; 51. Housing; 52. Solid-state cell; 53. Cover plate; 6. Electrical device. Detailed Implementation

[0139] The following describes in detail, with appropriate reference to the accompanying drawings, some embodiments of the solid-state battery cell, its fabrication method, solid-state battery, and power-consuming device of this application. However, some unnecessary details may be omitted. For example, detailed descriptions of well-known matters and repetitive descriptions of practically identical structures may be omitted. This is to avoid unnecessarily lengthy descriptions and to facilitate understanding by those skilled in the art. Furthermore, the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand this application and are not intended to limit the subject matter of the claims.

[0140] The "range" disclosed in this application can be defined in the form of a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of a particular range. Ranges defined in this way can include or exclude endpoints. Any endpoint can be included or excluded independently and can be combined arbitrarily; that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for a specific parameter, it is expected that ranges of 60-110 and 80-120 are also included. Furthermore, if minimum range values ​​1 and 2 are listed, and maximum range values ​​3, 4, and 5 are also listed, then the following ranges are all expected: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5. In this application, unless otherwise stated, the numerical range "ab" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0-5" indicates that all real numbers between "0" and "5" have been listed in this article; "0-5" is simply a shortened representation of these numerical combinations. Furthermore, when describing a parameter as an integer ≥ 2, it is equivalent to listing integers such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12 for that parameter. For instance, when describing a parameter as an integer selected from "2-10", it is equivalent to listing the integers 2, 3, 4, 5, 6, 7, 8, 9, and 10.

[0141] In this application, unless otherwise specified, "about" means within a reasonable range above and below the stated number, and the range of fluctuation may vary depending on the type and value of the stated number. For example, a range of ±10%, ±5%, ±2%, ±1%, etc., may be allowed. For example, taking "about 20°C" and its approximation as ±1°C, approximate values ​​such as 19°C, 19.5°C, etc., within the approximation range indicated by "about 20°C" should also be included in the range indicated by "about 20°C".

[0142] In this application, the terms "multiple," "various," "multiple items," "several," etc., unless otherwise specified, refer to a quantity greater than or equal to 2. For example, "one or more" means one or more (greater than or equal to) two. It can be understood that when "any number of" items are involved, it refers to any suitable combination of multiple items, that is, a combination of "any number of" items in a manner that does not conflict and enables the implementation of this application.

[0143] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0144] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment or implementation of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments. The term "implementation" as used herein has a similar understanding.

[0145] Those skilled in the art will understand that the order in which the steps are written in the methods of various embodiments or examples does not imply a strict execution order and does not constitute any limitation on the implementation process. The detailed execution order of each step should be determined by its function and possible internal logic. Unless otherwise specified, all steps of this application may be performed sequentially or randomly, but are preferably performed sequentially. For example, if method M includes steps (a) and (b), it means that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, method M may also include step (c), meaning that step (c) can be added to method M in any order. For example, method M may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0146] In this application, open-ended technical features or solutions described using terms such as "containing," "comprising," or "including" do not exclude additional members beyond those listed unless otherwise specified. They can be considered as providing both closed-ended features or solutions comprised of the listed members and open-ended features or solutions that include additional members beyond the listed members. For example, if 'a' includes a1, a2, and a3, it may also include other members or exclude additional members unless otherwise specified. This can be considered as providing both features or solutions where "a consists of a1, a2, and a3" or "a is selected from a1, a2, and a3," and features or solutions where "a includes not only a1, a2, and a3, but also other members."

[0147] In this application, unless otherwise specified, M (e.g., m1) means that m1 is a non-limiting example of M, and it is understood that M is not limited to m1.

[0148] In this application, "optionally," "optionally," and "optional" mean that something is optional, that is, it is selected from either "with" or "without." If multiple "options" appear in a technical solution, unless otherwise specified and there are no contradictions or mutual constraints, each "option" is independent. Unless otherwise specified, the descriptions such as "optionally include" and "optionally contain" in this application, taking "optionally include" as an example, mean "may include or not include."

[0149] In this application, unless otherwise specified, the features or solutions corresponding to "and / or" include any one of two or more of the related listed items, as well as any and all combinations of the related listed items. Any and all combinations include any two related listed items, any more related listed items, or a combination of all related listed items. For example, "M and / or N" represents the group consisting of M, N, and "a combination of M and N". "Containing M and / or N" can mean "containing M, containing N, and containing both M and N", or "containing M, containing N, or containing both M and N", and can be appropriately understood according to the context.

[0150] The terms “combinations of,” “any combination of,” and “any combination of” used in this article include all suitable combinations of any two or more of the listed items.

[0151] In this document, the term "suitable" in phrases such as "suitable combination," "suitable method," and "any suitable method" refers to the technical solution that enables the implementation of this application.

[0152] In this document, terms such as "preferred," "better," "more suitable," "ideal," "good," and "superior" are merely descriptions of more effective implementation methods or embodiments, and should be understood not to limit the scope of protection of this application. If multiple "preferred" terms appear in a technical solution, unless otherwise specified and there are no contradictions or mutual constraints, each "preferred" term shall be independent.

[0153] In this application, terms such as "further," "even more," "especially," "for example," "as," "example," and "exemplary" are used for descriptive purposes to indicate differences in content, but should not be construed as limiting the scope of protection of this application.

[0154] In this application, the terms "first aspect," "second aspect," "third aspect," "fourth aspect," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or quantity, nor should they be construed as implicitly indicating the importance or quantity of the indicated technical features. Moreover, "first," "second," "third," "fourth," etc., serve only as a non-exhaustive enumeration and should be understood not to constitute a closed limitation on quantity.

[0155] In the description of this application, it should be understood that the terms "length", "width", "thickness", "height", "upper", "lower", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0156] In this application, unless otherwise expressly specified and limited, the terms "connected," "linked," etc., should be interpreted broadly, for example, as a fixed connection, a detachable connection, or an integral part. Those skilled in the art can understand the meaning of the above terms in this application according to the circumstances.

[0157] In this application, unless otherwise expressly specified and limited, the phrase "above" or "below" the second feature can mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. In this application, unless otherwise expressly specified and limited, the phrase "above" or "below" the second feature can indicate a horizontal positional relationship, or it can simply indicate the existence of an attachment relationship without specifying a horizontal positional relationship.

[0158] In this application, unless otherwise specified, "stacked arrangement" is used to describe the positional relationship of multiple layered structures, meaning that multiple layered structures are stacked along their respective thickness directions. Those skilled in the art will understand its meaning. For example, "including stacked structural layer A and structural layer B" means that the stacking direction of structural layer A and structural layer B is along their respective thickness directions; that is, the thickness direction of structural layer A and the thickness direction of structural layer B are consistent or substantially consistent. It is understood that other intermediate structural layers are permitted to be disposed between structural layer A and structural layer B.

[0159] In this application, the term "room temperature" generally refers to 4℃ to 35℃, and may refer to 20℃ ± 5℃. In some embodiments or examples of this application, room temperature refers to 20℃ to 30℃.

[0160] In this application, when a unit is specified for a data range, if the unit is only followed by the right endpoint, it indicates that the units for the left and right endpoints are the same. For example, 3~5mm or 3-5mm both mean that the units for the left endpoint "3" and the right endpoint "5" are both mm (millimeters), and both have the same meaning as 3mm~5mm. Furthermore, similar descriptions of other parameters such as temperature and size are interpreted in the same way.

[0161] In this application, "greater than or equal to", "greater than or equal to", and "≥" have the same meaning and can be used interchangeably; "less than or equal to", "less than or equal to", and "≤" have the same meaning and can be used interchangeably; "greater than" can be equivalently represented as ">", and "less than" can be equivalently represented as "<". In this application, unless otherwise specified, "greater than or equal to" and "≥" can be considered as providing two additional solutions: "greater than" and "equal to". In this application, unless otherwise specified, "less than or equal to" and "≤" can be considered as providing two additional solutions: "less than" and "equal to".

[0162] In this application, the exemplary descriptions such as "in some implementations (or embodiments)" and "in one implementation (or embodiment)" may cover, but are not limited to, the following meanings: these solutions can be combined with other solutions in a suitable manner to form new technical solutions.

[0163] Unless otherwise stated, the improvements described in this application are not intended to be limited to any theoretical aspects.

[0164] In traditional solid-state batteries, the die-cut flexible tabs are located outside the active material layer of the electrode. After assembly into a cell, the flexible tabs suspend outside the active area of ​​the electrode. To allow for the connection of rigid tabs after multiple flexible tabs are attached together in the casing, a certain amount of internal space needs to be reserved for the flexible tabs. After the electrode assembly is packaged into the casing, the flexible tabs occupy a certain height space, resulting in a gap between the top of the electrode and the bottom of the casing. The area outside the tabs corresponding to this gap is usually empty, leading to fixed losses within the casing space. In addition, the sides of the flexible tabs are prone to breakage due to stress, increasing the cell impedance and affecting cell performance.

[0165] In this application, the "soft tab" can be obtained by die-cutting the current collector film during the electrode preparation process, thereby obtaining a current collector layer that matches the position of the electrode active material layer. That is, the soft tab and the current collector layer can be integrated. However, this is not a limitation. Non-limitingly, the material of the soft tab can be the same as the material of the corresponding current collector layer. In some non-limiting embodiments, the soft tab and the current collector layer can originate from the same current collector film, with at least a portion forming the current collector layer and at least another portion forming the soft tab. In this case, the soft tab and the current collector layer can be integrated.

[0166] In this application, unless otherwise specified, "hard tab" refers to the tab section located outside the battery casing, which is a metallic conductor that leads the positive and negative electrodes out of the battery cell. Without limitation, the hard tab of the positive electrode may be made of aluminum, and the hard tab of the negative electrode may be made of nickel.

[0167] Furthermore, during the die-cutting process of the tabs, the electrode active material in the electrode active material layer may be shed, which in turn affects the cycle performance and reliability of the assembled solid-state cell and solid-state battery.

[0168] Based on this, this application provides a method for manufacturing a solid-state battery cell, a solid-state battery, and a power-consuming device. This solid-state battery cell can improve the energy density and cycle performance of solid-state batteries; furthermore, it can improve the reliability of solid-state batteries; and the solid-state battery cell can also be manufactured using processes that can improve production yield.

[0169] In some embodiments, the solid-state battery cell includes a solid electrolyte portion and positive and negative electrode portions isolated by the solid electrolyte portion. Each electrode portion independently includes an electrode body and a tab connected to the electrode body. The electrode body includes at least one electrode layer, which includes a current collector layer and an electrode active material layer located on at least one side of the current collector layer. The solid-state battery cell has two composite grooves at at least one edge in its height direction for accommodating the positive and negative tabs. Each electrode layer has a groove corresponding to the two composite grooves. In the at least one electrode layer, the current collector layer is connected to the tab at the bottom of at least one groove. The electrode layer also includes a conductive adhesive layer located between the current collector layer and the electrode active material layer, at least covering the die-cut edge region of the groove where the tab is located (i.e., at least covering the die-cut edge region of the tab groove). This solid-state battery cell has improved energy density and cycle performance, and also improves the reliability of solid-state batteries.

[0170] Unless otherwise specified, the term "solid-state battery" as used in this application refers to a battery in which the electrolyte includes a solid electrolyte. Typically, a solid-state battery includes a positive electrode, a solid electrolyte, and a negative electrode. During charging and discharging, active ions repeatedly insert and extract between the positive and negative electrodes. The solid electrolyte acts as a conductor of ions between the positive and negative electrodes and also isolates them, preventing short circuits. Therefore, a separator, as found in traditional lithium-ion batteries, is not required in solid-state batteries. Solid-state batteries use a non-flammable solid electrolyte instead of the organic electrolyte in traditional liquid lithium-ion batteries, significantly improving battery safety. In addition to enhanced safety, solid-state batteries are better suited for high-energy-density positive and negative electrode materials and reduce system weight, thus facilitating improvements in energy density.

[0171] In this application, unless otherwise specified, "solid electrolyte section" refers to a structural section that includes a solid electrolyte. The solid electrolyte section includes at least one solid electrolyte layer, and the number of solid electrolyte layers matches the number of electrode layers in the electrode section.

[0172] In this application, unless otherwise specified, "solid electrolyte" refers to an electrolyte material or substance that exists in solid form during the storage and fabrication of solid-state batteries and their components, as well as during the operation of solid-state batteries. This includes, but is not limited to, solid electrolytes existing in solid form at room temperature.

[0173] In this application, unless otherwise specified, the "electrode portion" includes a positive electrode portion and a negative electrode portion. The positive electrode portion includes a positive electrode body and a positive electrode tab connected to the positive electrode body, and the negative electrode portion includes a negative electrode body and a negative electrode tab connected to the negative electrode body.

[0174] In this application, unless otherwise specified, the "electrode portion" includes an electrode body and a tab connected to the electrode body. The "electrode body" can be a positive electrode body or a negative electrode body. The electrode body in the positive electrode portion is a positive electrode body, and the electrode body in the negative electrode portion is a negative electrode body.

[0175] In this application, unless otherwise specified, an "electrode body" includes at least one electrode layer, and may include one or more electrode layers; the number of layers in the electrode body is consistent with the number of electrode layers in the electrode body. An "electrode body" can be a positive electrode body or a negative electrode body. A positive electrode body includes at least one positive electrode layer, and may include one or more positive electrode layers; the number of layers in the positive electrode body is consistent with the number of positive electrode layers in the positive electrode body. A negative electrode body includes at least one negative electrode layer, and may include one or more negative electrode layers; the number of layers in the negative electrode body is consistent with the number of positive electrode layers in the positive electrode body.

[0176] In this application, unless otherwise specified, a solid electrolyte layer is disposed between any adjacent positive and negative electrode layers. Therefore, the number of solid electrolyte layers in the solid electrolyte section matches the number of electrode layers in the electrode section.

[0177] Typically, a solid-state battery consists of a positive electrode layer, a solid electrolyte layer, and a negative electrode layer. During charging and discharging, active ions move back and forth between the positive and negative electrode layers, inserting and extracting. The solid electrolyte layer acts as a conductor of ions between the positive and negative electrode layers and also isolates them, thus preventing short circuits between the positive and negative electrodes.

[0178] In some embodiments, each electrode layer independently includes a current collector layer and an electrode active material layer located on at least one side of the current collector layer. In some embodiments, each positive electrode layer independently includes a positive current collector layer and a positive active material layer located on at least one side of the positive current collector layer, and each negative electrode layer independently includes a negative current collector layer and a negative active material layer located on at least one side of the negative current collector layer.

[0179] In this application, unless otherwise specified, "electrode active material layer" includes at least one of the positive electrode active material layer in the positive electrode layer and the negative electrode active material layer in the negative electrode layer. Depending on the specific circumstances, the electrode active material layer may refer to either the positive electrode active material layer or the negative electrode active material layer. It is understood that the positive electrode active material layer contains a positive electrode active substance, and the negative electrode active material layer contains a negative electrode active substance. In this application, "electrode active material layer" may also be abbreviated as "active material layer".

[0180] In this application, unless otherwise specified, "electrode portion" can be either a positive electrode portion or a negative electrode portion. The electrode portion in the positive electrode portion is the positive electrode portion, and the positive electrode portion is connected to the positive electrode body. The electrode portion in the negative electrode portion is the negative electrode portion, and the negative electrode portion is connected to the negative electrode body.

[0181] In this application, unless otherwise specified, a "tab portion" independently includes at least one tab, and each "tab" is independently connected to the current collector layer of the corresponding electrode layer. A positive tab portion includes at least one positive tab, which is connected to the positive current collector layer of the corresponding positive electrode layer. A negative tab portion includes at least one negative tab, which is connected to the negative current collector layer of the corresponding negative electrode layer. Each electrode layer may or may not have tabs, but at least one positive electrode body is connected to a positive tab, and at least one negative electrode body is connected to a negative tab.

[0182] It is understandable that the connection between the tab and the corresponding electrode body is at least a physical connection, and an electrical connection can also be achieved during battery cycling.

[0183] In this application, unless otherwise specified, "electrode layer" includes electrode active material. The electrode layer can be a positive electrode layer or a negative electrode layer, and "electrode active material" in the electrode layer refers to a material capable of reversibly inserting and extracting active ions. Unless otherwise specified, "negative electrode active material" refers to a material used in the negative electrode layer capable of reversibly inserting and extracting active ions; "positive electrode active material" refers to a material used in the positive electrode layer capable of reversibly extracting and inserting active ions. During solid-state battery charging, active ions are extracted from the positive electrode, pass through the solid electrolyte layer, and insert into the negative electrode; while during solid-state battery discharging, active ions are extracted from the negative electrode and insert into the positive electrode. The active ions are not particularly limited; non-limitingly, the active ions can be lithium ions, corresponding to a lithium-ion solid-state battery.

[0184] In some embodiments of the first aspect of this application, a solid-state battery cell is provided, comprising a plurality of electrode layers, wherein at least one electrode layer includes a current collector layer, a tab connected to the current collector layer, an electrode active material layer located on at least one side of the current collector layer, and a conductive adhesive layer located between the current collector layer and the electrode active material layer. The electrode layer has a tab groove at the tab, at least a portion of the tab being located within the tab groove, and the conductive adhesive layer at least covers the die-cut edge region of the tab groove. This solid-state battery cell can improve the energy density and cycle performance of solid-state batteries, and further improves the reliability of solid-state batteries.

[0185] In this application, unless otherwise specified, the height direction of the solid-state battery cell is denoted as the Y direction, the width direction as the X direction, and the thickness direction as the Z direction; the X, Y, and Z directions are perpendicular to each other.

[0186] In some embodiments, a solid-state battery cell is provided, comprising a solid electrolyte portion and two electrode portions, one of which is a positive electrode portion and the other is a negative electrode portion, the positive electrode portion and the negative electrode portion being isolated by the solid electrolyte portion; each electrode portion independently includes an electrode body and a tab portion connected to the electrode body, the electrode body including at least one electrode layer, the electrode layer including a current collector layer and an electrode active material layer located on at least one side of the current collector layer; the tab portion in the positive electrode portion is a positive tab portion, and the tab portion in the negative electrode portion is a negative tab portion;

[0187] At least one edge in the Y direction, the solid-state battery cell has two composite grooves, referred to as the first composite groove and the second composite groove respectively; the first composite groove is used to accommodate at least a part of the positive electrode tab, and the second composite groove is used to accommodate at least a part of the negative electrode tab; each electrode layer has grooves corresponding to the first composite groove and the second composite groove respectively.

[0188] In at least one electrode layer, a current collector layer is connected to a tab at the bottom of at least one groove, and the electrode layer further includes a conductive adhesive layer located between the current collector layer and the electrode active material layer, the conductive adhesive layer at least covering the die-cut edge region of the groove where the tab is located.

[0189] In this application, unless otherwise specified, "the solid-state cell has two composite grooves at at least one edge extending along the X direction" and "the solid-state cell has two composite grooves at at least one edge in the Y direction" have the same meaning and can be used interchangeably.

[0190] In this application, "the solid-state cell has two composite grooves at at least one edge extending along the X direction" means that the solid-state cell has two composite grooves, and these two composite grooves are located on the same edge extending along the X direction of the solid-state cell, or on different edges extending along the X direction of the solid-state cell. That is, the two composite grooves can be located on the same side of the solid-state cell in the Y direction, or on different sides of the solid-state cell in the Y direction. In the non-limiting embodiment shown in Figure 1, the first composite groove and the second composite groove are located on the same edge extending along the X direction of the solid-state cell. When the two composite grooves are located on different sides of the solid-state cell in the Y direction, the positive electrode tab and the negative electrode tab are located on different sides of the solid-state cell. In this case, by providing a cell active extension region in the solid-state cell, the improvement effect on volumetric energy density is more significant.

[0191] In this application, unless otherwise specified, in a solid-state battery cell, the active region that is highly consistent with the first composite groove and the second composite groove in the Y direction and located outside the first composite groove and the second composite groove in the X direction is referred to as the "cell active extension region".

[0192] In this application, unless otherwise specified, "active region" refers to the region in a solid-state battery cell where the electrode active material layer is disposed, as projected along the Z-direction. Unless otherwise specified, both the positive electrode body and the negative electrode body correspond to the active region, with the positive electrode body corresponding to the positive active region and the negative electrode body corresponding to the negative active region. Unless otherwise specified, the active region of a solid-state battery cell corresponds to the region other than the positive and negative electrode tabs, as projected along the Z-direction.

[0193] In this application, unless otherwise stated, along the X direction, due to the presence of the first composite groove and the second composite groove, the active region of the solid-state battery cell has a concave shape at the corresponding edge.

[0194] In this application, unless otherwise specified, the term "composite groove" can refer to a first composite groove, a second composite groove, or a combination of a first composite groove and a second composite groove. It can be appropriately understood in conjunction with the descriptive style. For example, "two composite grooves" refers to a combination of a first composite groove and a second composite groove.

[0195] In this application, unless otherwise specified, "first composite groove" refers to a groove in a solid-state battery cell for accommodating at least a portion of the positive electrode tab. At least a portion of the positive electrode tab is located within the concave region provided by the first composite groove. Unless otherwise specified, the positive electrode tab is connected to the positive electrode body at the bottom of the first composite groove. "Bottom of the first composite groove" refers to the side of the first composite groove furthest from the opening in the Y direction, which is also the top of the positive electrode body closest to the first composite groove in the Y direction at that location. Unless otherwise specified, the positive electrode tab is not connected to the side edges of the first composite groove, allowing the positive electrode tab to move in a direction perpendicular to the X direction.

[0196] In this application, unless otherwise specified, "second composite groove" refers to a groove in a solid-state battery cell for accommodating at least a portion of the negative electrode tab. At least a portion of the negative electrode tab is located within the recessed area provided by the second composite groove. Unless otherwise specified, the negative electrode tab is connected to the negative electrode body at the bottom of the second composite groove. "Bottom of the second composite groove" refers to the side of the second composite groove furthest from the opening in the Y direction, which is also the top of the negative electrode body closest to the second composite groove in the Y direction at that location. Unless otherwise specified, the negative electrode tab is not connected to the side edges of the second composite groove, allowing the negative electrode tab to move in a direction perpendicular to the X direction.

[0197] In the application, the terms "first" and "second" in "first composite groove" and "second composite groove" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or quantity, nor should they be construed as implicitly indicating the importance or quantity of the indicated technical features. Moreover, "first" and "second" serve only as a non-exhaustive enumeration and should be understood not to constitute a closed limitation on quantity.

[0198] In this application, unless otherwise specified, the "cell active extension region" is a part of the solid-state battery cell. The cell active extension region is an active area with an electrode active material layer. The cell active extension region has the same height as the first and second composite grooves in the height direction (Y direction) of the solid-state battery cell. In the width direction (X direction) of the solid-state battery cell, the cell active extension region is divided into discontinuous regions by the first and second composite grooves. The side contours of the first and second composite grooves extending along the Y direction are provided by adjacent cell active extension regions. The "cell active extension region" can also be described as a height region of the solid-state battery cell with two composite grooves in the Y direction. It is understood that the maximum height of the cell active extension region in the Y direction is greater than 0.

[0199] In this application, unless otherwise specified, a "conductive adhesive layer" is a structural layer that combines adhesion and conductivity between the current collector layer and the electrode active material layer. Typically, the adhesion between the current collector layer and the electrode active material layer is improved after a conductive adhesive layer is provided between them.

[0200] In some embodiments, after a conductive adhesive layer is provided between the current collector layer and the electrode active material layer, the conductivity between the current collector layer and the electrode active material layer is improved, and the resistivity of the electrode sheet is reduced.

[0201] In this application, "the groove where the tab is located" corresponds to the tab groove. The two sides of the tab groove are usually formed during the die-cutting of the tab.

[0202] In this application, unless otherwise specified, "the conductive adhesive layer at least covers the die-cut edge area of ​​the groove where the tab is located" means that the conductive adhesive layer extends a certain distance from the edge of the groove where the tab is located in a direction away from the groove, so that the conductive adhesive layer covers at least a portion of the current collector layer.

[0203] This solid-state battery cell features a first composite groove at the positive electrode tab, allowing it to bend inwards, and a second composite groove at the negative electrode tab, also allowing for inward bending. An active expansion region is formed in the area outside the first and second composite grooves along the width of the solid-state battery cell, at the same height. In other words, along the width of the solid-state battery cell, an active expansion region with the same height as the first and second composite grooves is provided in the space outside the positive and negative electrode tabs. This allows the solid-state battery cell to better utilize the space at the tabs, significantly increasing the volumetric energy density of the electrodes and thus improving the overall volumetric energy density of the solid-state battery. The two composite grooves also provide protection for the tabs, reducing the risk of tab breakage. Furthermore, a conductive adhesive layer is provided in the die-cut edge area of ​​the groove where the tab is located. On the one hand, the conductive adhesive layer can also provide good conductivity between the current collector layer and the electrode active material layer. In addition, the improved adhesion is beneficial to improving the cycle performance of the solid-state battery. On the other hand, it can improve the adhesion between the electrode active material layer and the current collector layer, which is conducive to forming a tab groove with neat edges when die-cutting the tab. It can reduce the shedding of electrode active material, which is beneficial to reducing the risk of internal short circuit and improving the reliability and production yield of the battery.

[0204] Furthermore, in one method for preparing this solid-state battery cell, when an electrode active material layer is introduced, the active pre-coating layer can also cover the tab groove area. The difference in adhesion between the active pre-coating layer and the current collector layer and the conductive adhesive layer can be used to more easily and selectively remove the electrode active material at the tab groove. This allows the electrode active material layer to form a neat edge contour during the die-cutting of the tab, reducing the shedding of electrode active material powder. This can improve the production yield of solid-state battery cells and solid-state batteries, and also improve the cycle performance of the prepared solid-state battery cells and solid-state batteries.

[0205] The adhesive force between the current collector layer and the electrode active material layer has a well-known meaning in the art and can be tested using instruments and methods known in the art. For example, the 180° tensile test method can be used, or, for example, the national standard GB / T2790-1995, "Test Method for 180° Peel Strength of Adhesives," can be referred to. The electrode sheet can be fixed to the test bench using double-sided tape, the electrode active material layer can be peeled off from the current collector layer, the peel force curve can be recorded, and the average value of the stable segment can be taken as the peel force test value F0. The adhesive force F between the current collector layer and the electrode active material layer can then be calculated using the following formula: F = F0 / width of the sample to be tested, where the unit of measurement for F is N / m.

[0206] Non-limitingly, the adhesion between the current collector layer and the electrode active material layer can be tested using the following method: Cut the electrode sheet into a sample of a certain length and width, for example, 100mm long × 10mm wide; take a stainless steel plate of a certain width, the width of which is greater than the width of the sample, for example, 25mm; apply double-sided tape to the stainless steel plate, the width of which is greater than the width of the sample; attach the sample to the double-sided tape, and roll it back and forth three times (300mm / min) with a pressure roller (the roller can weigh 2000g); bend the sample 180°, and manually peel the electrode active material layer from the current collector layer by a certain distance, such as 25mm; fix the sample in a testing machine (e.g., INSTRON). On 336), align the peeling surface with the force line of the testing machine. Peel continuously at 30 mm / min. Take the average value of the stable segment of the resulting peel force curve as the peel force F0. Then, the adhesion force between the electrode active material layer and the current collector layer in the test sample is F = F0 / width of the sample (unit: N / m). Unless otherwise specified, the temperature for testing the adhesion force between the current collector layer and the electrode active material layer can be 20℃~25℃, for example, 20℃, 22℃, 23℃, 25℃, etc.

[0207] In addition, the adhesion between the current collector layer and the electrode active material layer can also be tested by the following method: referring to the national standard GB / T2790-1995 Adhesives 180° Peel Strength Test Method, a 180° peel force test is performed at a certain peel speed (e.g., 50 mm / min), and the average peel force collected when the electrode active material layer with a length of 60 mm is completely peeled from the upper layer of the current collector is taken as the adhesion between the electrode active material layer and the current collector layer.

[0208] Non-limitingly, the following method can be used to determine whether "the conductive adhesive layer improves the adhesion between the current collector layer and the electrode active material layer":

[0209] Disassemble the battery, extract the electrode layer to be tested, and test the adhesion between the current collector layer and the electrode active material layer according to the aforementioned method, denoted as F1;

[0210] Extract the constituent materials of the electrode active material layer, lay them on one side of the current collector foil, and cold press at 360 MPa for 5 min to obtain the control electrode. Test the adhesion between the current collector layer and the electrode active material layer according to the aforementioned method, and record it as F2. When the electrode layer to be tested is a negative electrode layer, copper foil is used as the foil for preparing the control electrode. When the electrode layer to be tested is a positive electrode layer, aluminum foil is used as the foil for preparing the control electrode.

[0211] Comparing F1 and F2, if F1>F2, then it is determined that "the conductive adhesive layer improves the adhesion between the current collector layer and the electrode active material layer".

[0212] Non-limitingly, the following method can be used to determine whether "the conductive adhesive layer improves the conductivity between the current collector layer and the electrode active material layer":

[0213] The powder resistivity of the constituent materials of the electrode active material layer is compared with that of the constituent materials of the conductive adhesive layer. If the powder resistivity of the constituent materials of the conductive adhesive layer is lower, it is determined that "the conductive adhesive layer improves the conductivity between the current collector layer and the electrode active material layer". The powder resistivity of the constituent materials of the electrode active material layer and the conductive adhesive layer is obtained using the same testing method.

[0214] In this application, "powder resistivity" has a commonly known meaning in the art and can be tested using instruments and methods known in the art. For example, a four-probe method can be used, such as the ST2722 digital four-probe instrument. The powder resistivity of the sample can be determined according to or with reference to GB / T 30835-2014. Unless otherwise specified, the temperature for testing powder resistance can be 20℃ to 25℃, for example, 20℃, 22℃, 23℃, 25℃, etc.

[0215] In some embodiments, a solid-state battery cell 52 (see FIG1) is provided, which includes a solid electrolyte portion, a positive electrode portion and a negative electrode portion, wherein the positive electrode portion and the negative electrode portion are isolated by the solid electrolyte portion;

[0216] The positive electrode portion includes a positive electrode body and a positive electrode ear portion 1300 connected to the positive electrode body. The positive electrode body includes at least one positive electrode layer 10, and the positive electrode layer includes a positive electrode current collector layer 110 and a positive electrode active material layer 140 located on at least one side of the positive electrode current collector layer 110.

[0217] The negative electrode portion includes a negative electrode body and a negative electrode ear portion 3300 connected to the negative electrode body. The negative electrode body includes a negative electrode layer 30 in number matching the positive electrode layer 10. The negative electrode layer 30 includes a negative electrode current collector layer 310 and a negative electrode active material layer 340 located on at least one side of the negative electrode current collector layer 310.

[0218] The solid electrolyte section includes a solid electrolyte layer 20 that matches the total number of positive electrode layers 10 and negative electrode layers 30;

[0219] At least one edge in the Y direction, the solid-state battery cell has two composite grooves, referred to as the first composite groove 1302 and the second composite groove 3302, respectively; the first composite groove 1302 is used to accommodate at least a portion of the positive electrode tab 1300, and the second composite groove 3302 is used to accommodate at least a portion of the negative electrode tab 3300.

[0220] Each positive electrode layer 10 has a positive electrode tab groove 122 corresponding to the first composite groove 1302 and a first groove 124 corresponding to the second composite groove 3302; in at least one positive electrode layer 10, the positive electrode current collector layer 110 is connected to a positive electrode tab 130 at the bottom of at least one positive electrode tab groove 122, and the positive electrode layer 10 also includes a positive electrode conductive adhesive layer 120 located between the positive electrode current collector layer 110 and the positive electrode active material layer 140, and the positive electrode conductive adhesive layer 120 at least covers the die-cut edge area of ​​the positive electrode tab groove 122;

[0221] Each negative electrode layer 30 has a negative electrode tab groove 322 corresponding to the second composite groove 3302 and a second empty groove 324 corresponding to the first composite groove 1302; in at least one negative electrode layer 30, the negative electrode current collector layer 310 is connected to a negative electrode tab 330 at the bottom of at least one negative electrode tab groove 322, and the negative electrode layer 30 also includes a negative electrode conductive adhesive layer 320 located between the negative electrode current collector layer 310 and the negative electrode active material layer 340, and the negative electrode conductive adhesive layer 320 at least covers the die-cut edge area of ​​the negative electrode tab groove 322.

[0222] In the application, the terms "first groove" and "second groove" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or quantity, nor should they be construed as implicitly indicating the importance or quantity of the indicated technical features. Moreover, "first" and "second" serve only as a non-exhaustive enumeration and should be understood not to constitute a closed limitation on quantity.

[0223] In some embodiments, the conductive adhesive layer at least covers the die-cut edge region of each groove in the electrode layer.

[0224] In this application, unless otherwise specified, "the conductive adhesive layer at least covers the die-cut edge area of ​​each groove in the electrode layer" means that the conductive adhesive layer extends a distance from the edge of each groove in a direction away from the groove, so that the conductive adhesive layer covers at least a portion of the current collector layer.

[0225] By ensuring that the conductive adhesive layer covers at least the die-cut edge area of ​​each groove in the electrode layer, the increased coverage area of ​​the conductive adhesive layer is more conducive to improving the adhesion and conductivity between the current collector layer and the electrode active material layer, which is beneficial to further improving the cycle performance of the solid-state battery. On the other hand, it can also improve the edge neatness of the electrode active material layer at each groove, reduce the shedding of electrode active material at each groove, which is more conducive to reducing the risk of internal short circuits and improving the reliability and production yield of the battery.

[0226] In some embodiments, the conductive adhesive layer at least covers the cut edge region of the electrode layer.

[0227] In this application, unless otherwise specified, "the conductive adhesive layer at least covers the cut edge region of the electrode layer" means that the conductive adhesive layer extends a distance from the cut edge of the electrode layer in a direction away from the cut edge of the electrode layer, so that the conductive adhesive layer covers at least a portion of the current collector layer.

[0228] By ensuring that the conductive adhesive layer at least covers the cut edge area of ​​the electrode layer, it is more conducive to improving the adhesion and conductivity between the current collector layer and the electrode active material layer, which is beneficial to further improving the cycle performance of solid-state batteries. On the other hand, it can improve the edge neatness of the electrode active material layer at each cut position, further reduce the shedding of electrode active material, which is more conducive to reducing the risk of internal short circuits, and more conducive to improving the reliability and production yield of batteries.

[0229] In some embodiments, the first composite groove and the second composite groove are located on the same edge of the solid-state cell extending along the X direction. That is, in the Y direction, the first composite groove and the second composite groove are located on the same side of the solid-state cell.

[0230] In some embodiments, the first composite groove and the second composite groove are located at different side edges of the solid-state cell extending along the X direction. That is, in the Y direction, the first composite groove and the second composite groove are located on different sides of the solid-state cell.

[0231] In this application, the height of the positive electrode body in the Y direction can be denoted as H. P Let H be the height of the negative electrode body in the Y direction. N The height of the solid-state battery cell in the Y direction is denoted as H0.

[0232] In some implementations, H P >(H0-H Δ ).

[0233] In some implementations, H N >(H0-H Δ ).

[0234] In some implementations, H P >(H0-H Δ And H N >(H0-H Δ ).

[0235] In this application, unless otherwise specified, "the height of the positive electrode body in the Y direction" refers to the maximum height of the positive electrode body in the Y direction. In some embodiments, the height of the positive electrode body in the Y direction is equal to the sum of the height of the positive electrode body at the first composite groove and the height of the first composite groove.

[0236] In this application, unless otherwise specified, "the height of the negative electrode body in the Y direction" refers to the maximum height of the negative electrode body in the Y direction. In some embodiments, the height of the negative electrode body in the Y direction is equal to the sum of the height of the negative electrode body at the second composite groove and the height of the second composite groove.

[0237] In this application, unless otherwise specified, "height of solid-state cell in the Y direction" refers to the maximum height of the electrode body in the Y direction. Unless otherwise specified, "height of solid-state cell in the Y direction" does not include the height of the tab.

[0238] In this application, unless otherwise stated, the "maximum height of the active extension area of ​​the cell in the Y direction" is consistent with the maximum depth of the first composite groove and the second composite groove in the Y direction.

[0239] Solid-state cells have a certain length of extension in the X direction and a certain height of extension in the Y direction. The two top edges of a solid-state cell with a certain distance between them in the Y direction can be referred to as "the two sides of the solid-state cell extending in the X direction" or "the two sides of the solid-state battery in the Y direction".

[0240] In some implementations, H N It is equal to H0. At this point, the space at the tab can be used to the maximum extent to set the electrode active material layer, thereby maximizing the volumetric energy density of the solid-state cell and solid-state battery.

[0241] In some embodiments, in the electrode layer including the conductive adhesive layer, the region between the electrode active material layer and the current collector layer includes a covered area with the conductive adhesive layer, and may or may not include a blank area without the conductive adhesive layer; the percentage of the covered area relative to the area of ​​the electrode active material layer, projected along the Z direction, can be 64% to 100%, more preferably 80% to 100%, but is not limited thereto. The percentage of the covered area relative to the area of ​​the electrode active material layer, projected along the Z direction, can also be any of the following percentages or a range selected from any two of the following percentages: 64%, 70%, 75%, 80%, 81%, 85%, 90%, 92%, 95%, 96%, 98%, 99%, 100%, etc.

[0242] In some embodiments, in the electrode layer including the conductive adhesive layer, the projected area of ​​the conductive adhesive layer coincides with that of the electrode active material layer when projected along the Z direction. In this case, the percentage of the covered area relative to the area of ​​the electrode active material layer is 100% when projected along the Z direction.

[0243] Increasing the coverage area of ​​the conductive adhesive layer is more conducive to improving the adhesion and electronic conductivity between the current collector layer and the electrode active material layer, which is beneficial to further improving the cycle performance of solid-state batteries.

[0244] In some embodiments, the conductive adhesive layer includes an adhesive matrix and a conductive material. Non-limitingly, the adhesive matrix may include polyolefin resins, and more particularly, polyolefin resins and polyolefin-modified resins. Non-limiting examples of polyolefin resins may include one or more of the following polyolefins and polyolefin-modified resins based on any of the following polyolefin resins: polyethylene, polypropylene, ethylene-vinyl acetate copolymer, styrene-butadiene copolymer, styrene-ethylene-butene-styrene block copolymer, styrene-isoprene-styrene block copolymer, and amorphous polyalphaolefins. Non-limitingly, the polyolefin-modified resin may include a copolymer of any of the aforementioned polyolefin resins with maleic anhydride. In some embodiments, the polyolefin-modified resin includes a copolymer of any of the aforementioned polyolefin resins with maleic anhydride and petroleum resin.

[0245] In some embodiments, the adhesive matrix comprises a polyolefin resin; further, the polyolefin resin may include, but is not limited to, one or more of the following polyolefin resins and polyolefin modified resins based on the following polyolefin resins: polyethylene, polypropylene, ethylene-vinyl acetate copolymer, styrene-butadiene copolymer, styrene-ethylene-butene-styrene block copolymer, styrene-isoprene-styrene block copolymer, and amorphous polyalphaolefin; the polyolefin modified resin is a copolymer of polyolefin resin with maleic anhydride and petroleum resin.

[0246] In some embodiments, the adhesive matrix comprises a polyolefin-modified resin. Further, the polyolefin-modified resin may be, but is not limited to, a copolymer of a polyolefin resin and maleic anhydride and petroleum resin in a mass ratio of 30:(2-5):(8-12). The polyolefin resin may include one or more of the polyolefin resins listed above.

[0247] Non-limiting, the weight-average molecular weight of polyolefin resins can be from 1000 kDa to 1500 kDa. The weight-average molecular weight of polyolefin resins can also be any of the following values ​​or a range selected from any two of the following numbers: 1000 kDa, 1100 kDa, 1200 kDa, 1300 kDa, 1400 kDa, 1500 kDa, etc.

[0248] Without limitation, the polyolefins in polyolefin resins may include one or more of polyethylene, polypropylene, ethylene-vinyl acetate copolymer, styrene-butadiene copolymer, styrene-ethylene-butene-styrene block copolymer, styrene-isoprene-styrene block copolymer, and amorphous polyalphaolefins.

[0249] Non-limitingly, the polyolefin-modified resin can be a copolymer of any of the aforementioned polyolefin resins modified with maleic anhydride. Introducing maleic anhydride into the polyolefin can increase the polarity of the molecular chain segments, thereby improving the adhesion between the current collector layer and the electrode active material layer.

[0250] Non-limiting, the polyolefin modified resin can be a copolymer of any of the aforementioned polyolefin resins with maleic anhydride and petroleum resin. Those skilled in the art can select appropriate amounts of maleic anhydride and petroleum resin according to the need to improve adhesion.

[0251] Those skilled in the art can identify the components of the conductive adhesive layer using one or more of the following detection methods, including but not limited to: Fourier transform infrared (FT-IR) spectroscopy, ultraviolet spectroscopy, and proton nuclear magnetic resonance (NMR) spectroscopy. 1Methods include ¹H NMR, gel permeation chromatography (GPC), high-performance liquid chromatography (HPLC), mass spectrometry, X-ray diffraction (XRD), single-crystal X-ray diffraction (SCXRD), and inductively coupled plasma atomic emission spectrometry (ICP). The sample preparation and testing methods for these methods are known to those skilled in the art, and the test parameters can be appropriately adjusted according to the structure of the compound and the characteristics of the sample. As a non-limiting example, HPLC can be used to determine the molecular weight of viscous matrices (such as polyolefin resins).

[0252] In some embodiments, the mass ratio of structural units derived from polyolefin resin, maleic anhydride and petroleum resin in the polyolefin modified resin is 30:(2-5):(8-12), optionally 30:(2-5):(9-11), further optionally 30:(2-5):(9.5-10.5), and even more preferably 30:(3-5):(9.8-10.2).

[0253] Non-limiting examples of conductive materials may include carbon conductive materials. Non-limiting examples of carbon conductive materials may include one or more of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, carbon nanofibers, and mesophase carbon microspheres. In some embodiments, the carbon conductive material includes one or more of carbon black, carbon nanotubes, graphene, and mesophase carbon microspheres.

[0254] Non-limitingly, in the conductive adhesive layer, the mass ratio of the adhesive matrix to the conductive material can be (0.6–1.5):1, optionally (0.8–1.4):1, further optionally (1–1.4):1, or any of the following ratios or a range selected from any two ratios: 3:5, 0.7:1, 4:5 (i.e., 0.8:1), 0.9:1, 1:1, 1.1:1, 1.2:1, 1.25:1, 1.3:1, 1.4:1, 1.5:1, etc.

[0255] Non-limitingly, the total mass of the adhesive matrix and the conductive material in the conductive adhesive layer can be 90% to 98% of the total mass, or any of the following percentages or a range selected from any two of the following percentages: 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, etc. As an example, the total mass of the adhesive matrix and the conductive material in the conductive adhesive layer can be any of the following ranges: 90% to 96%, 91% to 96%, etc.

[0256] Non-limitingly, the mass percentage of the adhesive matrix in the conductive adhesive layer can be 35% to 70%, optionally 35% to 56%, or any of the following percentages or a range selected from any two of the following percentages: 35%, 36%, 38%, 40%, 42%, 44%, 45%, 46%, 48%, 50%, 52%, 54%, 55%, 56%, 60%, etc. The mass percentage of the adhesive matrix in the conductive adhesive layer can also be any of the following ranges: 40% to 60%, etc.

[0257] Non-limitingly, the mass percentage of conductive material in the conductive adhesive layer can be 15% to 60%, optionally 38% to 60%, or any of the following percentages or a range selected from any two of the following percentages: 20%, 30%, 35%, 36%, 38%, 40%, 42%, 44%, 45%, 46%, 48%, 50%, 52%, 54%, 55%, 56%, 58%, 60%, etc. The mass percentage of conductive material in the conductive adhesive layer can also be any of the following ranges: 20% to 60%, 20% to 50%, etc.

[0258] In this application, unless otherwise specified, the type of adhesive substrate and its mass percentage in the conductive adhesive layer, the type of conductive material and its mass percentage in the conductive adhesive layer, the total mass of the adhesive substrate and the conductive material in the conductive adhesive layer, and the mass ratio of the adhesive substrate and the conductive material in the conductive adhesive layer can be combined in any suitable manner, thereby adjusting the resistivity of the electrode layer and the adhesion between the current collector layer and the electrode active material layer in the electrode layer.

[0259] In some embodiments, the resistivity of the electrode layer, including the conductive adhesive layer, is less than or equal to 1000 Ω·m, and the adhesion between the current collector layer and the electrode active material layer in the electrode layer is greater than or equal to 1 N / m.

[0260] In some embodiments, the resistivity of the electrode layer, including the conductive adhesive layer, is 10 Ω·m to 1000 Ω·m, and the adhesion between the current collector layer and the electrode active material layer in the electrode layer is 1 N / m to 50 N / m.

[0261] In some embodiments, the resistivity of the electrode layer including the conductive adhesive layer is less than or equal to 1000 Ω·m, and optionally less than or equal to 200 Ω·m. Non-limitingly, the resistivity of the electrode layer including the conductive adhesive layer can be any of the following values ​​or a range selected from any two of the following values: 10 Ω·m, 12 Ω·m, 15 Ω·m, 16 Ω·m, 18 Ω·m, 20 Ω·m, 25 Ω·m, 30 Ω·m, 35 Ω·m, 40 Ω·m, 45 Ω·m, 50 Ω·m, 60 Ω·m, 70 Ω·m, 80 Ω·m, 90 Ω·m. The resistivity of the electrode layer, including the conductive adhesive layer, can be 10 Ω·m to 200 Ω·m, etc., ranging from 100 Ω·m, 120 Ω·m, 150 Ω·m, 160 Ω·m, 180 Ω·m, 200 Ω·m, 250 Ω·m, 300 Ω·m, 400 Ω·m, 500 Ω·m, 600 Ω·m, 700 Ω·m, 800 Ω·m, 900 Ω·m, 1000 Ω·m, etc. For example, the resistivity of the electrode layer, including the conductive adhesive layer, can be 10 Ω·m to 200 Ω·m.

[0262] In some embodiments, the adhesion force between the current collector layer and the electrode active material layer in the electrode layer is greater than or equal to 1 N / m, and optionally, greater than or equal to 3 N / m. Non-limitingly, the adhesion force between the current collector layer and the electrode active material layer in the electrode layer can be any of the following values ​​or a range selected from any two of the following values: 1 N / m, 2 N / m, 3 N / m, 4 N / m, 5 N / m, 6 N / m, 8 N / m, 10 N / m, 12 N / m, 14 N / m, 15 N / m, 16 N / m, 18 N / m, 20 N / m, 22 N / m, 24 N / m. The values ​​of N / m, 25 N / m, 26 N / m, 28 N / m, 30 N / m, 32 N / m, 34 N / m, 35 N / m, 36 N / m, 38 N / m, 40 N / m, 42 N / m, 44 N / m, 45 N / m, 46 N / m, 48 N / m, 50 N / m, etc., for example, the adhesion force between the current collector layer and the electrode active material layer in the electrode layer can be 3 N / m to 20 N / m.

[0263] In some embodiments, the resistivity of the electrode layer including the conductive adhesive layer is 10 Ω·m to 200 Ω·m, and the adhesion between the current collector layer and the electrode active material layer in the electrode layer is 3 N / m to 20 N / m.

[0264] The resistivity of the electrode layer, including the conductive adhesive layer, can be tested using film resistivity testing methods known in the art, and reference can be made to the electrode resistivity testing methods described below. Unless otherwise specified, the test temperature for the resistivity of the electrode layer, including the conductive adhesive layer, can be 20°C to 25°C, for example, 20°C, 22°C, 23°C, 25°C, etc.

[0265] The adhesion between the current collector layer and the electrode active material layer in the electrode layer can also be referred to the previous text, and will not be repeated here. The test temperature can be 20℃~25℃, for example 20℃, 22℃, 23℃, 25℃, etc.

[0266] By controlling the resistivity of the electrode layer and the adhesion between the current collector layer and the electrode active material layer within the aforementioned range, both conductivity and adhesion can be balanced.

[0267] In some embodiments, the electrode layer including the conductive adhesive layer satisfies one or more of the following characteristics:

[0268] The viscous matrix includes polyolefin resins, which include one or more of the following polyolefins and their modifiers: polyethylene, polypropylene, ethylene-vinyl acetate copolymer, styrene-butadiene copolymer, styrene-ethylene-butene-styrene block copolymer, styrene-isoprene-styrene block copolymer, and amorphous polyalphaolefins; the polyolefin modifiers include copolymers of the aforementioned polyolefin resins modified by one or more units of maleic anhydride and petroleum resins.

[0269] The conductive material includes carbon conductive materials, which include one or more of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, carbon nanofibers, and mesophase carbon microspheres; optionally, the carbon conductive material includes one or more of carbon black, carbon nanotubes, graphene, and mesophase carbon microspheres.

[0270] The combined mass of the adhesive matrix and the conductive material accounts for 90% to 98% of the mass of the conductive adhesive layer.

[0271] In the conductive adhesive layer, the mass ratio of the adhesive matrix to the conductive material is 1:1 to 1.4:1.

[0272] By selecting the aforementioned conductive adhesive layer composition, it is beneficial to balance the adhesion and conductivity between the electrode active material layer and the current collector layer, which is beneficial to better improve the cycle performance of solid-state batteries, and also more beneficial to achieve a comprehensive improvement in the cycle performance, reliability and production yield of solid-state batteries.

[0273] Non-limitingly, the conductive adhesive layer may optionally include additives. The addition of additives can improve the thermal stability and long-term storage properties of the conductive adhesive layer, and inhibit carbonization or aging of the conductive adhesive layer at high temperatures. Non-limitingly, the additives in the conductive adhesive layer may include one or more of antioxidants and anti-aging agents. Non-limiting examples of additives in the conductive adhesive layer may include paraffin wax. Non-limitingly, the mass percentage of the additives in the conductive adhesive layer may be less than or equal to 10%, further may be 2% to 10%, and may also be any of the following percentages or a range selected from any two of the following percentages: 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, etc. Non-limitingly, the mass percentage of the additives in the conductive adhesive layer may also be any of the following ranges: 3% to 10%, 4% to 10%, 2% to 9%, 3% to 9%, 4% to 9%, etc. In some embodiments, the conductive adhesive layer includes paraffin wax. Further, the mass percentage of paraffin wax in the conductive adhesive layer may be less than or equal to 10%, further may be 2% to 10%, or may be any of the following percentages or a range selected from any two of the following percentages: 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, etc., or may be any of the following ranges: 3% to 10%, 4% to 10%, 2% to 9%, 3% to 9%, 4% to 9%, etc.

[0274] In some embodiments, the electrode active material layer includes a conductive agent; in the same electrode layer, the mass percentage of the conductive material in the conductive adhesive layer is higher than the mass percentage of the conductive agent in the electrode active material layer, based on one side of the current collector layer.

[0275] By controlling the content gradient of conductive material in the conductive adhesive layer and conductive agent in the electrode active material layer, it is more beneficial to improve the conductivity between the electrode active material layer and the current collector layer.

[0276] In some embodiments, the thickness of the conductive adhesive layer in the corresponding electrode layer, measured on one side of the current collector layer, is 0.5 μm to 3 μm, and can be selected as 0.5 μm to 1.5 μm. The thickness of the conductive adhesive layer in the corresponding electrode layer, measured on one side of the current collector layer, can also be any of the following thicknesses or a range selected from any two of the following thicknesses: 0.5 μm, 0.6 μm, 0.8 μm, 1 μm, 1.0 μm, 1.2 μm, 1.5 μm, 1.6 μm, 1.8 μm, 2 μm, 2.0 μm, 2.2 μm, 2.4 μm, 2.5 μm, 2.6 μm, 2.8 μm, 3 μm, etc. In some embodiments, the thickness of the conductive adhesive layer in the respective electrode layer, measured on one side of the current collector layer, is selected from any suitable range of the following: 0.5μm to 2.5μm, 0.5μm to 2μm, 0.6μm to 3μm, 0.6μm to 2.5μm, 0.6μm to 2μm, 1μm to 1.5μm, etc.

[0277] By controlling the thickness of the conductive adhesive layer within the aforementioned range, it is beneficial to improve the adhesion and conductivity between the electrode active material layer and the current collector layer while also taking into account the high energy density advantage of solid-state cells.

[0278] In some embodiments, the active region in the solid-state battery cell located at the height of the first composite groove and the second composite groove is referred to as the active extension region of the battery cell;

[0279] The height of the electrode body at the active extension region of the cell is higher than the height of the electrode body at any composite groove.

[0280] In the aforementioned solid-state cell structure, the height of the positive electrode body at the active extension region of the cell is higher than the height of the positive electrode body at the first composite groove, and the height of the negative electrode body at the active extension region of the cell is higher than the height of the negative electrode body at the second composite groove. This allows the solid-state cell to make better use of the space at the tabs, thereby significantly increasing the space volume occupied by the electrode part in the solid-state cell and significantly improving the volumetric energy density of the solid-state cell and solid-state battery.

[0281] In this application, the height of the solid-state cell in the Y direction can be denoted as H0; the maximum height of the cell's active extension region in the Y direction can be denoted as H. Δ The utilization rate ψ of the active extension region of the battery cell in the Y direction Y =H Δ / H0×100%;

[0282] Let W0 denote the width of the solid-state cell in the X direction, and let W denote the width of the cell's active extension region in the X direction. Δ The utilization rate ψ of the active extension region of the cell in the X direction X =W Δ / W0×100%;

[0283] Let A0 denote the projected area of ​​the solid-state battery cell along the Z direction, and let A denote the projected area of ​​the active extension region of the battery cell along the Z direction. Δ The two-dimensional utilization rate ψ of the active extension region of the battery cell A =A Δ / A0×100%.

[0284] In this application, unless otherwise specified, "projected area of ​​solid-state cell along the Z direction" refers to the projected area of ​​the electrode body portion along the Z direction, excluding the projected area of ​​the tab portion along the Z direction.

[0285] In some implementations, the solid-state battery cell satisfies one or more of the following characteristics:

[0286] H Δ≥0.05mm, optionally, 0.05mm≤H Δ ≤1mm;

[0287] ψ Y ≥0.05%, optionally, 0.1% ≤ψ Y ≤2%;

[0288] W Δ ≥50mm, optional, 50mm≤W Δ ≤1000mm;

[0289] ψ X ≥60%, optionally, 60% ≤ψ X ≤95%;

[0290] ψ A ≥0.04%, optionally, 0.04% ≤ψ A ≤1.5%.

[0291] In some implementations, the solid-state battery cell satisfies one or more of the following characteristics:

[0292] 0.05mm≤H Δ ≤1mm;

[0293] 0.1%≤ψ Y ≤2%;

[0294] 50mm≤W Δ ≤1000mm;

[0295] 60%≤ψ X ≤95%;

[0296] 0.04%≤ψ A ≤1.5%.

[0297] Without limitation, H Δ ≥0.05mm, optionally, 0.05mm≤H Δ ≤1mm. Non-limitingly, H Δ It can also be any of the following values, or a range consisting of any two of the following values: 0.05mm, 0.06mm, 0.08mm, 0.10mm, 0.1mm, 0.15mm, 0.2mm, 0.20mm, 0.25mm, 0.4mm, 0.5mm, 0.6mm, 0.8mm, 0.9mm, 1.0mm, 1mm, etc.

[0298] Without restriction, ψ Y ≥0.05%, optionally, ψ Y ≥0.1%, and further optionally, 0.1% ≤ ψ Y ≤2%. Without limitation, ψY It can also be any of the following percentages, or an interval selected from any two of the following percentages: 0.05%, 0.06%, 0.08%, 0.1%, 0.2%, 0.4%, 0.5%, 0.6%, 0.8%, 1%, 1.2%, 1.4%, 1.5%, 1.6%, 1.8%, 2%, etc. Non-restrictively, ψ Y It can also be any of the following ranges: 0.05% ≤ ψ Y ≤2%, etc.

[0299] By adjusting the height parameter h of the active extension region of the battery cell Δ and utilization parameter ψ Y One or two of the aforementioned adjustments are beneficial for better utilizing the space in the height direction at the pole position.

[0300] Without limitation, W Δ ≥50mm, optional, 50mm≤W Δ ≤1000mm. Non-limitingly, W Δ It can also be any of the following values, or a range consisting of any two of the following values: 50mm, 60mm, 80mm, 100mm, 120mm, 150mm, 200mm, 250mm, 300mm, 400mm, 500mm, 600mm, 700mm, 800mm, 900mm, 1000mm, etc.

[0301] Without restriction, ψ X ≥60%, optionally, 60% ≤ψ X ≤95%. (Unrestricted, ψ) X It can also be any of the following percentages, or an interval selected from any two of the following percentages: 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, etc., for example, ψ X Selectable from the following range: ψ X ≥70%, 70%≤ψ X ≤95%, etc.

[0302] By adjusting the width parameter w of the active extension region of the battery cell Δ and utilization parameter ψ X One or two of the aforementioned adjustments are beneficial for better utilizing the space in the width direction at the electrode position.

[0303] In some implementations, solid-state cells satisfy: ψ A ≥0.04%.

[0304] In some implementations, solid-state cells satisfy: ψ A ≥0.05%.

[0305] In some implementations, the solid-state cell satisfies: 0.04% ≤ ψ A ≤1.5%.

[0306] Without restriction, ψ A It can also be any of the following percentages, or an interval selected from any two of the following percentages: 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.15%, 0.16%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.2%, 1.4%, 1.5%, etc., for example, ψ A The following ranges can be selected: 0.05%–1.5%, 0.06%–1.5%, 0.1%–1.5%, 0.15%–1.5%, 0.04%–1.2%, 0.05%–1.2%, 0.06%–1.2%, 0.1%–1.2%, 0.15%–1.2%, 0.16%–1.5%, 0.16%–1.2%, etc.

[0307] By increasing the two-dimensional utilization rate ψ of the cell's active extension region A Within the aforementioned range, adjustments are beneficial for better utilization of the unused space at the electrode tabs. It is understandable that, compared to solid-state cells without an active extension region, solid-state cells with an active extension region typically exhibit a higher percentage increase in volumetric energy density than ψ0. A .

[0308] In some embodiments, the length of the positive electrode tab in the Y direction in its extended state is greater than the height of the first composite groove in the Y direction. In some embodiments, the positive electrode tab includes a positive electrode tab bend located within the first composite groove.

[0309] In some embodiments, the length of the negative electrode tab in the Y direction in its extended state is greater than the height of the second composite groove in the Y direction. In some embodiments, the negative electrode tab includes a negative electrode tab bend located within the second composite groove.

[0310] In some embodiments, the length of the positive electrode ear in the extended state in the Y direction is greater than the height of the first composite groove in the Y direction, and the length of the negative electrode ear in the extended state in the Y direction is greater than the height of the second composite groove in the Y direction.

[0311] In some embodiments, the positive electrode ear includes a positive electrode ear bend located within a first composite groove; the negative electrode ear includes a negative electrode ear bend located within a second composite groove.

[0312] In some embodiments, the positive electrode tab includes a positive electrode tab bend located within the first composite groove, and the length of the positive electrode tab in the Y direction in the extended state is greater than the height of the first composite groove in the Y direction.

[0313] The negative electrode ear includes a bent portion of the negative electrode ear located within the second composite groove, and the length of the negative electrode ear in the Y direction in the extended state is greater than the height of the second composite groove in the Y direction.

[0314] In some embodiments, the grooves in the electrode layer where the tabs are provided are referred to as tab grooves, and the extension height of any tab in the Y direction is greater than the height of the corresponding tab groove in the Y direction.

[0315] By reserving a certain extension height for the positive or negative tab, it is easy to use it as a soft tab to be transferred to a hard tab in subsequent processes.

[0316] In some embodiments, at least a portion of the tab has a bent section within the corresponding groove.

[0317] At least a portion of the tab can be bent into the reserved groove, which helps to further increase the volume occupancy of the electrode part in the solid-state cell, and can significantly improve the volumetric energy density of the solid-state cell and solid-state battery.

[0318] In this application, the extension height of the positive electrode ear in the Y direction is denoted as H. PJ When the positive and negative electrode tabs are located on the same side of the solid-state cell in the height direction, in some embodiments, H PJ ≥H Δ Optionally, H PJ >H Δ .

[0319] In this application, the extension height of the negative electrode ear in the Y direction is denoted as H. NJ When the positive and negative electrode tabs are located on the same side of the solid-state cell in the height direction, in some embodiments, H NJ ≥H Δ Optionally, H NJ >H Δ .

[0320] Taking the dry process as an example, during the preparation of positive or negative electrode sheets, when attaching the self-supporting electrode sheet to the corresponding current collector film, by controlling the coating height in the Y direction to be less than the height of the current collector film, after die-cutting, the extension height of the formed tab can be greater than the corresponding groove height. It can be understood that when a positive electrode sheet is prepared using a positive self-supporting electrode sheet and a positive current collector film, a positive tab is formed at the positive tab groove; similarly, when a negative electrode sheet is prepared using a negative self-supporting electrode sheet and a negative current collector film, a negative tab is formed at the negative tab groove.

[0321] In this application, unless otherwise specified, "the extension height of the electrode" refers to the height of the electrode in the Y direction when it is in the extended state.

[0322] In some embodiments, the width of the positive electrode tab in the X direction is smaller than the width of the first composite groove in the X direction.

[0323] In some embodiments, the width of the negative electrode ear in the X direction is smaller than the width of the second composite groove in the X direction.

[0324] In some embodiments, the width of the positive electrode tab in the X direction is smaller than the width of the first composite groove in the X direction; the width of the negative electrode tab in the X direction is smaller than the width of the second composite groove in the X direction.

[0325] In some embodiments, in the X direction, there is a gap between the positive electrode ear and the two side edges of the first composite groove, and a gap between the negative electrode ear and the two side edges of the second composite groove.

[0326] By leaving a certain gap on both sides of the corresponding electrode tab at the composite groove, a suitable space for movement can be reserved for the positive and negative electrode tabs, and it is also possible to bend the positive and negative electrode tabs into the composite groove more easily.

[0327] In some embodiments, in the X direction, there is a gap between the positive electrode ear and the two side edges of the first composite groove, and a gap between the negative electrode ear and the two side edges of the second composite groove. Non-limiting, the width of any gap in the X direction can be independently 10 μm to 5000 μm, and can be independently selected from 0.1 mm to 1 mm, but is not limited thereto. The width of any gap in the X direction can be independently any of the following values ​​or selected from any two of the following values: 10 μm, 50 μm, 100 μm, 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 1.5 mm, 2 mm, 3 mm, 4 mm, etc., for example, selected from the following ranges: 0.2 mm to 1 mm, 0.15 mm to 1 mm, 0.3 mm to 1 mm, 0.2 mm to 0.5 mm, 0.15 mm to 0.5 mm, 0.3 mm to 0.5 mm, etc.

[0328] By controlling the size of the gap within a suitable range, it is possible to prevent the positive and negative electrodes from rubbing against adjacent structural layers in different states, while also maximizing the proportion of the extended active area.

[0329] In some implementations, the solid-state battery cell has a stacked structure.

[0330] Without limitation, the size of solid-state battery cells can be any of the sizes known to be applicable in various fields, including but not limited to the size specifications of battery products such as button batteries and laptop batteries.

[0331] In some embodiments, the solid electrolyte section includes at least one solid electrolyte layer. It is understood that a solid electrolyte layer is disposed between any adjacent positive and negative electrode layers. Therefore, the number of solid electrolyte layers in the solid electrolyte section matches the number of electrode layers in the electrode section.

[0332] In some embodiments, the positive electrode body includes at least one positive electrode layer, each positive electrode layer having a groove corresponding to the first composite groove and the second composite groove respectively, and a positive electrode tab is provided at the groove corresponding to the first composite groove in the at least one positive electrode layer.

[0333] The negative electrode body includes at least one negative electrode layer, each negative electrode layer having a groove corresponding to the second composite groove and the first composite groove respectively, and a negative electrode tab is provided at the groove corresponding to the second composite groove in the at least one negative electrode layer.

[0334] The solid electrolyte section includes at least one solid electrolyte layer, and any adjacent positive electrode layer and negative electrode layer are isolated by the solid electrolyte layer; each solid electrolyte layer has a hollow groove corresponding to the first composite groove and the second composite groove respectively.

[0335] In this application, unless otherwise specified, the groove in the positive electrode layer corresponding to the first composite groove is referred to as the "positive electrode tab groove". The positive electrode tab groove may be provided with a positive electrode tab or be an empty groove, but at least one positive electrode tab groove is provided with a positive electrode tab. It can be understood that the grooves in the positive electrode layer corresponding to the second composite groove are all empty grooves.

[0336] In this application, unless otherwise specified, the groove in the negative electrode layer corresponding to the second composite groove is referred to as the "negative electrode tab groove". The negative electrode tab groove may be provided with a negative electrode tab or be an empty groove, but at least one negative electrode tab groove is provided with a negative electrode tab. It can be understood that the grooves in the negative electrode layer corresponding to the first composite groove are all empty grooves.

[0337] In this application, unless otherwise specified, "empty groove" includes grooves in the electrode layer where no tabs are provided, and also grooves in the solid electrolyte layer corresponding to the two composite grooves. The empty grooves involved in this application include at least a first empty groove in the positive electrode layer corresponding to the second composite groove, a second empty groove in the negative electrode layer corresponding to the first composite groove, a fourth empty groove in the solid electrolyte layer corresponding to the first composite groove, and a third empty groove in the solid electrolyte layer corresponding to the second composite groove.

[0338] In some embodiments, the positive electrode portion includes a positive electrode body and a positive electrode tab connected to the positive electrode body. The positive electrode body includes at least one positive electrode layer, which includes a positive electrode current collector layer and a positive electrode active material layer located on at least one side of the positive electrode current collector layer. Each positive electrode layer has a groove corresponding to a first composite groove and a second composite groove, respectively. In the at least one positive electrode layer, the positive electrode current collector layer is connected to a positive electrode tab at the bottom of at least one groove. The positive electrode layer also includes a positive electrode conductive adhesive layer located between the positive electrode current collector layer and the positive electrode active material layer. The positive electrode conductive adhesive layer at least covers the die-cut edge region of the groove where the positive electrode tab is located. All the positive electrode tabs connected to the positive electrode body together constitute at least a part of the positive electrode tab portion.

[0339] The negative electrode portion includes a negative electrode body and a negative electrode tab connected to the negative electrode body. The negative electrode body includes at least one negative electrode layer, which includes a negative electrode current collector layer and a negative electrode active material layer located on at least one side of the negative electrode current collector layer. Each negative electrode layer has a groove corresponding to a first composite groove and a second composite groove, respectively. In the at least one negative electrode layer, the negative electrode current collector layer is connected to the bottom of at least one groove with a negative electrode tab. The negative electrode layer also includes a negative electrode conductive adhesive layer located between the negative electrode current collector layer and the negative electrode active material layer. The negative electrode conductive adhesive layer at least covers the die-cut edge area of ​​the groove where the negative electrode tab is located. All the negative electrode tabs connected to the negative electrode body together constitute at least a part of the negative electrode tab portion.

[0340] The solid electrolyte section includes at least one solid electrolyte layer, and any adjacent positive electrode layer and negative electrode layer are isolated by the solid electrolyte layer; each solid electrolyte layer is provided with an empty groove corresponding to the first composite groove and the second composite groove respectively.

[0341] In this application, unless otherwise specified, "positive electrode tab groove" refers to the groove in the positive electrode layer corresponding to the position of the positive electrode tab. For any positive electrode layer, a positive electrode tab may or may not be provided at the positive electrode tab groove, as long as the number of positive electrode tabs connected to all positive electrode layers is greater than or equal to 1.

[0342] In this application, unless otherwise specified, "negative electrode tab groove" refers to the groove in the negative electrode layer corresponding to the position of the negative electrode tab. For any negative electrode layer, a negative electrode tab may or may not be provided at the negative electrode tab groove, as long as the number of negative electrode tabs connected to all negative electrode layers is greater than or equal to 1.

[0343] When a solid-state battery cell adopts the aforementioned stacked structure, at the first composite groove, the positive electrode tab groove on the positive electrode layer, the empty groove on the negative electrode layer, and the empty groove on the solid electrolyte layer can be combined to form a concave space that allows the positive electrode tab to bend inward; at the second composite groove, the negative electrode tab groove on the negative electrode layer, the empty groove on the positive electrode layer, and the empty groove on the solid electrolyte layer can be combined to form a concave space that allows the negative electrode tab to bend inward. This significantly expands the active area of ​​the solid-state battery cell, allowing it to better utilize the space at the tabs, greatly increasing the volume occupied by the electrodes in the solid-state battery cell, and significantly improving the volumetric energy density of the solid-state battery cell and the solid-state battery. The two composite grooves also provide protection for the tabs, reducing the risk of tab breakage. Furthermore, a conductive adhesive layer is provided in the die-cut edge area of ​​the groove where the tab is located. On the one hand, the conductive adhesive layer can also provide good conductivity between the current collector layer and the electrode active material layer. In addition, the improved adhesion is beneficial to improving the cycle performance of the solid-state battery. On the other hand, it can improve the adhesion between the electrode active material layer and the current collector layer, which is conducive to forming a tab groove with neat edges when die-cutting the tab. It can reduce the shedding of electrode active material, which is beneficial to reducing the risk of internal short circuit and improving the reliability and production yield of the battery.

[0344] Furthermore, in one method for preparing this solid-state battery cell, when an electrode active material layer is introduced, the active pre-coating layer can also cover the tab groove area. The difference in adhesion between the active pre-coating layer and the current collector layer and the conductive adhesive layer can be used to more easily and selectively remove the electrode active material at the tab groove. This allows the electrode active material layer to form a neat edge contour during the die-cutting of the tab, reducing the shedding of electrode active material powder. This can improve the production yield of solid-state battery cells and solid-state batteries, and also improve the cycle performance of the prepared solid-state battery cells and solid-state batteries.

[0345] In the thickness direction of the positive electrode layer, the positive electrode active material layer can be located on at least one side of the positive electrode current collector layer. The positive electrode active material layer can be located on only one side of the positive electrode current collector layer, or it can be located on both sides of the positive electrode current collector layer. In some embodiments, the thickness direction of the positive electrode layer is consistent with the Z-direction.

[0346] In the thickness direction of the negative electrode layer, the negative electrode active material layer may be located on at least one side of the negative electrode current collector layer. The negative electrode active material layer may be located on only one side of the negative electrode current collector layer, or it may be located on both sides of the negative electrode current collector layer. In some embodiments, the thickness direction of the negative electrode layer is consistent with the Z-direction.

[0347] In a non-limiting sense, the positive electrode tab can be made of the same material as the positive electrode current collector layer; furthermore, the positive electrode tab and the positive electrode current collector layer can originate from the same current collector membrane. This type of positive electrode tab can be classified as a "soft electrode tab".

[0348] In a non-limiting sense, the negative electrode tab can be made of the same material as the negative electrode current collector layer; furthermore, the negative electrode tab can originate from the same current collector membrane as the negative electrode current collector layer. This type of negative electrode tab can be classified as a "soft electrode tab".

[0349] When the solid-state battery cell adopts the aforementioned stacked structure, at the first composite groove, the positive electrode tab groove on the positive electrode layer, the empty groove on the negative electrode layer, and the empty groove on the solid electrolyte layer can be combined to form a concave space that allows the positive electrode tab to bend inward; at the second composite groove, the negative electrode tab groove on the negative electrode layer, the empty groove on the positive electrode layer, and the empty groove on the solid electrolyte layer can be combined to form a concave space that allows the negative electrode tab to bend inward.

[0350] In some embodiments, all the positive electrode tabs connected to the positive electrode body together constitute at least a part of the positive electrode tab portion. In this case, the positive electrode tab portion may also include a positive electrode hard electrode tab portion.

[0351] In some implementations, all the positive electrode tabs connected to the positive electrode body together constitute the positive electrode tab portion.

[0352] In some embodiments, all the negative electrode tabs connected to the negative electrode body together constitute at least a portion of the negative electrode tab portion. In this case, the negative electrode tab portion may also include a negative electrode hard electrode tab portion.

[0353] In some implementations, all the negative electrode tabs connected to the negative electrode body together constitute the negative electrode tab portion.

[0354] In some implementations, the positive electrode body has a single positive electrode layer; the negative electrode body has a single negative electrode layer.

[0355] In some implementations, the positive electrode body has multiple positive electrode layers; the negative electrode body has the same number of negative electrode layers as the positive electrode body.

[0356] When the number of positive electrode layers in the positive electrode body is multi-layered and the number of negative electrode layers in the negative electrode body is a matching multi-layered structure, the stacked structure corresponds to a multi-layered stacked structure. In this case, by utilizing the aforementioned cell active extension region structure design, it is beneficial to gain more volumetric energy density in the tab space.

[0357] Without limitation, the number of positive electrode layers in the positive electrode body can be one or more. The more positive electrode layers in the positive electrode body, the thicker the battery. The appropriate number of positive electrode layers can be selected according to the size requirements of the solid-state battery.

[0358] Based on the number of positive electrode layers in the positive electrode body, the number of positive electrode layers can be one or more. Generally, the number of negative electrode layers in the negative electrode body is not less than the number of positive electrode layers in the positive electrode body.

[0359] In some implementations, the number of positive electrode layers in the positive electrode body is equal to the number of negative electrode layers in the negative electrode body.

[0360] In some implementations, the number of positive electrode layers N in the positive electrode body P ≥1, optionally, N P ≥2, and further optionally, N P ≥5, and further optionally, N P ≥10, and further optionally, N P ≥20, and further optionally, N P ≥30, and further optionally, N P ≥40, and further optionally, N P ≥50. (Unrestricted) The number of cathode layers N in the cathode body. P The range is 1 to 60, with a selectable range of 2 to 60. The number of positive electrode layers N in the positive electrode body. P It can also be any of the following values ​​or an interval composed of any two of the following values: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, etc.

[0361] In some implementations, the number of positive electrode layers in the positive electrode body is 1.

[0362] In some embodiments, multiple positive electrode layers in the positive electrode body are connected to positive electrode tabs; multiple negative electrode layers in the negative electrode body are connected to negative electrode tabs.

[0363] In this application, unless otherwise specified, when multiple positive electrode layers in the positive electrode body are connected to positive electrode tabs, the multiple positive electrode tabs are stacked in the Z direction to form a multi-layer positive electrode tab structure. In this case, the "positive electrode tab" can also be referred to as a positive electrode tab stack.

[0364] In this application, unless otherwise specified, when multiple negative electrode layers in the negative electrode body are connected to negative electrode tabs, the multiple negative electrode tabs are stacked in the Z direction to form a multi-layered negative electrode tab structure. In this case, the "negative electrode tab" can also be referred to as a negative electrode tab stack.

[0365] When multiple positive electrode layers in the positive electrode body are connected to positive electrode tabs and multiple negative electrode layers in the negative electrode body are connected to negative electrode tabs, it is more conducive to saving the waste of internal space caused by the stacking of multiple electrode tabs.

[0366] In this application, the "tab laminate" includes a positive tab laminate and a negative tab laminate. It is understood that each tab in the tab laminate is connected to a corresponding electrode layer, and further, each tab is connected to a current collector layer within the corresponding electrode layer. The multiple positive tabs in the positive tab laminate are each connected to a corresponding positive electrode layer, and further, each tab is connected to a positive current collector layer within the corresponding positive electrode layer. The multiple negative tabs in the negative tab laminate are each connected to a corresponding negative electrode layer, and further, each tab is connected to a negative current collector layer within the corresponding negative electrode layer.

[0367] In a solid-state battery cell, the positive electrode layer is provided with a recess corresponding to the second composite groove, which can be referred to as the first recess; the negative electrode layer is provided with a recess corresponding to the first composite groove, which can be referred to as the second recess; the solid electrolyte layer is provided with recesses corresponding to the first composite groove and the second composite groove respectively. The recess corresponding to the first composite groove can be referred to as the fourth recess, and the recess corresponding to the second composite groove can be referred to as the third recess.

[0368] In a solid-state battery cell, the positive tab recess, the fourth empty recess, and the second empty recess are matched to provide a first composite recess that accommodates at least a portion of the positive tab, and the negative tab recess, the third empty recess, and the first empty recess are matched to provide a second composite recess that accommodates at least a portion of the negative tab.

[0369] In a second aspect of this application, a method for preparing a solid-state battery cell is provided, which can be used to prepare the solid-state battery cell described in the first aspect of this application.

[0370] Non-limitingly, a pre-fabricated positive electrode, a pre-fabricated solid electrolyte membrane, and a pre-fabricated negative electrode can be stacked sequentially, with the solid electrolyte membrane placed between the positive and negative electrode, and then rolled to obtain a solid-state battery cell. Non-limitingly, the rolling can be done by cold rolling or hot rolling, but is not limited to these methods.

[0371] In some embodiments, the solid-state battery cell can be prepared by a method including steps S100, S200, S300, S400, and S500:

[0372] S100: Prepare the required number of positive electrode sheets, each positive electrode sheet including a positive current collector layer and a positive active material layer located on at least one side of the positive current collector layer; at at least one edge in the height direction of the positive electrode sheet, the positive electrode sheet is provided with a positive tab groove and a first empty groove; at least one positive electrode sheet also includes a positive tab connected to the positive current collector layer and a conductive adhesive layer located between the positive current collector layer and the positive active material layer, the conductive adhesive layer being referred to as the positive conductive adhesive layer, the positive tab being connected to the bottom of the positive tab groove of the corresponding positive electrode sheet, the positive conductive adhesive layer at least covering the die-cut edge area of ​​the positive tab groove;

[0373] S200: Prepare the required number of negative electrode sheets, each negative electrode sheet including a negative electrode current collector layer and a negative electrode active material layer located on at least one side of the negative electrode current collector layer; at least one edge in the height direction of the negative electrode sheet, the negative electrode sheet is provided with a negative electrode tab groove and a second empty groove; at least one negative electrode sheet also includes a negative electrode tab connected to the negative electrode current collector layer and a conductive adhesive layer located between the negative electrode current collector layer and the negative electrode active material layer, the conductive adhesive layer being referred to as the negative electrode conductive adhesive layer, the negative electrode tab being connected to the bottom of the negative electrode tab groove of the corresponding negative electrode sheet, the negative electrode conductive adhesive layer at least covering the die-cut edge area of ​​the negative electrode tab groove;

[0374] S300: Prepare a quantity of solid electrolyte membrane sheets, the solid electrolyte membrane sheets having a fourth cavity groove and a third cavity groove;

[0375] S400: According to the required quantities, positive electrode plates, solid electrolyte membranes, and negative electrode plates are stacked, with the positive and negative electrode plates separated by the solid electrolyte membrane. The outlines of the positive electrode tab groove, the fourth empty groove, and the second empty groove are aligned to form a first composite groove. The outlines of the negative electrode tab groove, the third empty groove, and the first empty groove are aligned to form a second composite groove, thereby obtaining a laminated part. Each positive electrode plate constitutes a positive electrode portion, each negative electrode plate constitutes a negative electrode portion, and each solid electrolyte membrane constitutes a solid electrolyte portion. Each positive electrode tab in the positive electrode portion constitutes a positive electrode tab soft segment, and at least a portion of the positive electrode tab soft segment is accommodated in the first composite groove. Each negative electrode tab in the negative electrode portion constitutes a negative electrode tab soft segment, and at least a portion of the negative electrode tab soft segment is accommodated in the second composite groove.

[0376] S500: The laminated components are rolled to form solid-state battery cells.

[0377] Based on the number of positive electrode plates, the number of positive electrode plates stacked can be one or more. Generally, the number of negative electrode plates stacked is not less than the number of positive electrode plates stacked.

[0378] Those skilled in the art can implement the various steps of the solid-state battery cell fabrication method under the guidance of the fabrication method provided in the second aspect of this application, using methods known in the art. For example, laser cutting technology can be used for electrode die-cutting, but it is not limited to this.

[0379] In some implementations, the number of layers of the positive electrode is equal to the number of layers of the negative electrode.

[0380] In some embodiments, there are multiple positive electrode sheets stacked together; the outlines of multiple positive electrode tabs of multiple positive electrode sheets are aligned and together form a positive electrode tab stack, at least a portion of the positive electrode tab stack is accommodated in a first composite groove; the outlines of multiple negative electrode tabs of multiple negative electrode sheets are aligned and together form a negative electrode tab stack, at least a portion of the negative electrode tab stack is accommodated in a second composite groove.

[0381] In this application, unless otherwise specified, the "empty groove" in the positive electrode sheet, negative electrode sheet, and solid electrolyte membrane refers to the space reserved in the corresponding groove before assembly into a solid-state battery cell. After assembly into a battery cell, it can participate in the formation of a composite groove to provide space for the matching tab. For example, in some embodiments, the positive electrode sheet used to form the positive electrode layer, in addition to having a positive electrode tab groove that matches the position of the positive electrode tab, also has a first empty groove reserved for matching the position of the negative electrode tab in the solid-state battery cell; the negative electrode sheet used to form the negative electrode layer, in addition to having a negative electrode tab groove that matches the position of the negative electrode tab, also has a second empty groove reserved for matching the position of the positive electrode tab in the solid-state battery cell; the solid electrolyte membrane used to form the solid electrolyte layer has a third empty groove reserved for matching the position of the negative electrode tab in the solid-state battery cell and a fourth empty groove reserved for matching the position of the positive electrode tab in the solid-state battery cell.

[0382] In the application, the terms "first recess," "second recess," "third recess," and "fourth recess" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or quantity, nor should they be construed as implicitly indicating the importance or quantity of the indicated technical features. Moreover, "first," "second," "third," and "fourth" serve only as a non-exhaustive enumeration and should be understood not to constitute a closed limitation on quantity.

[0383] In some embodiments, the method for preparing a solid-state battery cell may further include one or both of steps S600 and S700:

[0384] S600: Bend at least a portion of the positive electrode tab into the first composite groove to obtain a bent portion of the positive electrode tab in the first composite groove;

[0385] S700: At least a portion of the negative electrode tab is bent into the second composite groove to obtain the negative electrode tab bent portion in the second composite groove.

[0386] In some embodiments, the number of positive electrode layers is greater than 1. In this case, the positive electrode portion corresponds to the positive electrode tab stack, and the negative electrode tab portion corresponds to the negative electrode tab stack. The method for preparing solid-state battery cells may also include one or both of steps S610 and S710:

[0387] S610: Bend at least a portion of the positive electrode tab laminate into the first composite groove to obtain the positive electrode tab bent portion in the first composite groove;

[0388] S710: Bend at least a portion of the negative electrode tab laminate into the second composite groove to obtain the negative electrode tab bent portion in the second composite groove.

[0389] In this application, unless otherwise specified, "tab stack" can refer to a positive tab stack or a negative tab stack. Specifically, a "positive tab stack" refers to a stack of multiple positive tabs stacked in the thickness direction (Z direction) of a solid-state battery cell; a "negative tab stack" refers to a stack of multiple negative tabs stacked in the thickness direction (Z direction) of a solid-state battery cell.

[0390] In this application, unless otherwise specified, the "empty grooves" in the positive electrode sheet, negative electrode sheet, and solid electrolyte layer refer to the spaces reserved in the corresponding grooves before assembly into a battery cell. After assembly, these grooves can participate in forming a composite groove to accommodate the tab stack. For example, in some embodiments, the positive electrode sheet used to form the positive electrode layer, in addition to having a positive electrode tab groove to accommodate the positive electrode tab, also has a first empty groove reserved for accommodating the negative electrode tab stack in the battery cell; the negative electrode sheet used to form the negative electrode layer, in addition to having a negative electrode tab groove to accommodate the negative electrode tab, also has a second empty groove reserved for accommodating the positive electrode tab stack in the battery cell; the solid electrolyte membrane used to form the solid electrolyte layer has a third empty groove reserved for accommodating the negative electrode tab stack in the battery cell and a fourth empty groove reserved for accommodating the positive electrode tab stack in the battery cell.

[0391] In some embodiments, step S400 includes: stacking multiple positive electrode sheets, multiple solid electrolyte membrane sheets, and multiple negative electrode sheets in the required quantities, such that the positive electrode sheets and negative electrode sheets are isolated by the solid electrolyte membrane sheets; aligning the outlines of the positive electrode tab groove, the fourth empty groove, and the second empty groove to form a first composite groove; aligning the outlines of the negative electrode tab groove, the third empty groove, and the first empty groove to form a second composite groove, thereby obtaining a laminated component; wherein each positive electrode sheet constitutes a positive electrode portion, each negative electrode sheet constitutes a negative electrode portion, and each solid electrolyte membrane sheet constitutes a solid electrolyte portion; the outlines of each positive electrode tab in the positive electrode portion are aligned to form a positive electrode tab laminate, at least a portion of the positive electrode tab laminate is accommodated in the first composite groove; the outlines of each negative electrode tab in the negative electrode portion are aligned to form a negative electrode tab laminate, at least a portion of the negative electrode tab laminate is accommodated in the second composite groove.

[0392] The positive electrode active material layer in the positive electrode sheet can be produced using a dry process, but is not limited to this method.

[0393] Taking the dry process as an example, the constituent materials of the positive electrode active material layer can be mixed evenly, rolled to form a positive electrode self-supporting sheet, and then bonded together with a positive electrode current collector film (such as aluminum foil) with a conductive adhesive layer, and hot rolled to obtain the positive electrode sheet. Non-limiting examples of hot rolling temperature include 160℃~180℃.

[0394] In some embodiments, the positive electrode sheet including the positive tab can be prepared by a method including the following steps (see Figures 2(a) and 3, the positive electrode sheet is also a positive electrode sheet including a conductive adhesive layer):

[0395] On the surface of the positive electrode current collector membrane 111, the positive electrode body region 1112 and the positive electrode inactive region 1110, which are adjacent to each other by a first boundary line 1000, are identified. The first boundary line 1000 extends along the width direction of the positive electrode current collector membrane 111 in a concave shape, such that the positive electrode inactive region 1110 includes a positive electrode tab concave region 1220 and a first concave region 1240 that are concave towards the positive electrode body region 1112, and the positive electrode tab concave region 1220 and the first concave region 1240 are separated by the positive electrode body region 1112; wherein, the positive electrode tab concave region 1220 is matched with the positive electrode tab groove 122, and the first concave region 1240 is matched with the first empty groove 124.

[0396] On at least one side surface of the positive electrode current collector film 111, a positive electrode conductive adhesive layer 120 is applied to at least a portion of the positive electrode body region 1112 with the first dividing line 1000 as the coating boundary.

[0397] On at least one side surface of the positive electrode current collector film 111 to which the positive electrode conductive adhesive layer 120 is attached, a positive electrode active pre-coating layer 1402 is applied so that the positive electrode active pre-coating layer 1402 covers the positive electrode body region 1112, the positive electrode tab recess region 1220 and the first recess region 1240.

[0398] Remove the portion of the positive electrode active pre-coating 1402 covering the concave region 1220 and the first concave region 1240 of the positive electrode tab, exposing the corresponding positive electrode current collector film surface, to obtain a positive electrode die slice; wherein, the remaining portion of the positive electrode active pre-coating 1402 corresponds to the positive electrode active material layer 140, and the portion of the positive electrode current collector film covered by the positive electrode active material layer 140 corresponds to the positive electrode current collector layer 110;

[0399] Die-cutting the positive electrode sheet according to the first dividing line 1000 to form a positive electrode sheet 100; wherein, the die-cutting of the positive electrode sheet according to the first dividing line 1000 includes: die-cutting out the corresponding contour of the positive electrode active material layer 140 except for the positive electrode tab recess 1220, die-cutting out the contour of the two side edges of the positive electrode tab groove 122 and the positive electrode tab 130 connected to the positive electrode current collector layer 110 in the positive electrode tab recess 1220, and die-cutting out the first empty groove 124 in the first recess 1240 according to the first dividing line 1000.

[0400] In the process of preparing the aforementioned positive electrode sheet including the positive electrode tab, before coating the positive active pre-coating layer, a conductive adhesive layer with a concave region is provided on the positive current collector film. On the one hand, this can improve the adhesion and conductivity between the positive active material layer and the positive current collector film. On the other hand, when the positive active material layer is introduced, the positive active pre-coating layer can cover the concave region as well. The difference in adhesion between the positive active pre-coating layer and the positive current collector film and the conductive adhesive layer can be used to more easily and selectively remove the positive active material in the concave region, thereby exposing the surface of the positive current collector film at the corresponding position. Then, the positive electrode tab can be die-cut in the concave region. The conductive adhesive layer can improve the adhesion and conductivity between the positive active material layer and the positive current collector film. When die-cutting the positive electrode tab, it is beneficial to form a neat edge contour, which can reduce the shedding of positive active material powder, thereby improving the production yield of solid-state cells and solid-state batteries, and also improving the cycle performance of the prepared solid-state cells and solid-state batteries. In the prepared positive electrode sheet, the positive tab can be bent inward into the positive tab groove, thereby increasing the space occupancy of the positive active material layer and improving the volumetric energy density of the solid-state cell and solid-state battery. Furthermore, the positive tab groove also provides protection for the positive tab, reducing the risk of tab breakage.

[0401] The negative electrode active material layer in the negative electrode sheet can be prepared by a dry method.

[0402] Taking the dry process as an example, the constituent materials of the negative electrode active material layer can be mixed evenly, rolled to form a self-supporting negative electrode sheet, and then bonded together with a negative electrode current collector film (such as copper foil) with a conductive adhesive layer, and hot rolled to obtain the negative electrode sheet. Non-limiting examples of hot rolling temperature include 160℃~180℃.

[0403] In some embodiments, the negative electrode sheet including the negative electrode tab is prepared by a method comprising the following steps (see Figure 2(b) and Figure 4, the negative electrode sheet also includes a conductive adhesive layer):

[0404] On the surface of the negative electrode current collector membrane 311, the negative electrode body region 3112 and the negative electrode inactive region 3110, which are adjacent to each other by a second boundary line 3000, are identified. The second boundary line 3000 extends along the width direction of the negative electrode current collector membrane 311 in a concave shape, such that the negative electrode inactive region 3110 includes a negative electrode tab concave region 3220 and a second concave region 3240 that are concave toward the negative electrode body region 3112, and the negative electrode tab concave region 3220 and the second concave region 3240 are separated by the negative electrode body region 3112; wherein, the negative electrode tab concave region 3220 is matched with the negative electrode tab groove 322, and the second concave region 3240 is matched with the second empty groove 324.

[0405] On at least one side surface of the negative electrode current collector film 311, a negative electrode conductive adhesive layer 320 is applied to at least a portion of the negative electrode body region 3112 with the second dividing line 3000 as the coating boundary.

[0406] On at least one side surface of the negative electrode current collector membrane 311 to which the negative electrode conductive adhesive layer 320 is attached, an additional negative electrode active pre-coating layer 3402 is applied so that the negative electrode active pre-coating layer 3402 covers the negative electrode body region 3112, the negative electrode tab recess region 3220 and the second recess region 3240.

[0407] Remove the portion of the negative electrode active pre-coating 3402 covering the negative electrode tab recess 3220 and the second recess 3240 to expose the corresponding negative electrode current collector film surface and obtain a negative electrode die slice; wherein, the remaining portion of the negative electrode active pre-coating 3402 corresponds to the negative electrode active material layer 340, and the portion of the negative electrode current collector film covered by the negative electrode active material layer 340 corresponds to the negative electrode current collector layer 310.

[0408] The negative electrode sheet to be die-cut is formed by die-cutting the negative electrode sheet according to the second boundary line 3000. The die-cutting process of the negative electrode sheet to be die-cut according to the second boundary line 3000 includes: die-cutting out the corresponding contour of the area of ​​the negative electrode active material layer 340 except for the negative electrode tab concave region 3220; die-cutting out the contour of the two side edges of the negative electrode tab groove 322 and the negative electrode tab 330 connected to the negative electrode current collector layer 310 in the negative electrode tab concave region 3220; and die-cutting out the second empty groove 324 in the second concave region 3240 according to the second boundary line 3000.

[0409] In the process of preparing the aforementioned negative electrode sheet including the negative electrode tab, before coating the negative active pre-coating layer, a conductive adhesive layer with a concave region is provided on the negative current collector film. On the one hand, this can improve the adhesion and conductivity between the negative active material layer and the negative current collector film. On the other hand, when the negative active material layer is introduced, the negative active pre-coating layer can cover the concave region as well. The difference in adhesion between the negative active pre-coating layer and the negative current collector film and the conductive adhesive layer can be used to more easily and selectively remove the negative active material in the concave region, thereby exposing the surface of the negative current collector film at the corresponding position. Then, the negative electrode tab can be die-cut in the concave region. The conductive adhesive layer can improve the adhesion and conductivity between the negative active material layer and the negative current collector film. When die-cutting the negative electrode tab, it is beneficial to form a neat edge contour, which can reduce the shedding of negative active material powder. This can improve the production yield of solid-state cells and solid-state batteries, and also improve the cycle performance of the prepared solid-state cells and solid-state batteries. In the prepared negative electrode sheet, the negative electrode tab can be bent inward into the negative electrode tab groove, thereby increasing the space occupancy of the negative electrode active material layer and improving the volumetric energy density of the solid-state cell and solid-state battery. Furthermore, the negative electrode tab groove also provides protection for the negative electrode tab, reducing the risk of tab breakage.

[0410] The method for coating a conductive adhesive layer during the preparation of electrode sheets can be a dry method, which can be used to coat a positive conductive adhesive layer during the preparation of a positive electrode sheet and a negative conductive adhesive layer during the preparation of a negative electrode sheet. A hot melt dispensing machine (such as ET-420D) can be used to form the conductive adhesive layer on the current collector layer. For example, the dispensing temperature can be 150°C to 180°C. A hot melt extrusion process can also be used, with single-screw extrusion molding and the width and thickness controlled by the nozzle. The hot melt temperature can be 150°C to 180°C, but is not limited to this. Non-limiting examples of dispensing temperature or hot melt temperature include 160°C, 170°C, 180°C, etc., and can also be selected from any range of the aforementioned two temperatures.

[0411] Solid electrolyte membranes can be prepared using methods that are not limited to the following: The solid electrolyte membrane material is die-cut using laser cutting technology to obtain a solid electrolyte membrane that matches the shape of the positive and negative electrode sheets. A fourth recess is formed at a predetermined position of the positive electrode tab in the positive electrode sheet, and a third recess is formed at a predetermined position of the negative electrode tab in the negative electrode sheet. Further, the fourth recess corresponds to a first composite recess in the solid-state battery cell for accommodating at least a portion of the positive electrode tab, and the third recess corresponds to a second composite recess in the solid-state battery cell for accommodating at least a portion of the negative electrode tab.

[0412] In a non-limiting manner, solid electrolyte membrane materials can be prepared by any suitable known method, such as pressing the constituent raw materials of solid electrolyte membrane materials (such as solid electrolyte powder, but not limited thereto) into a membrane shape under pressure to obtain solid electrolyte membrane materials.

[0413] In some embodiments, the method for fabricating solid-state batteries satisfies one or more of the following characteristics:

[0414] In the process of preparing a positive electrode sheet including a positive electrode tab, a positive electrode conductive adhesive layer is coated on at least one side surface of the positive electrode current collector film, with a first dividing line as the coating boundary, over the entire area of ​​the positive electrode body region.

[0415] In the process of preparing a negative electrode sheet including a negative electrode tab, a negative electrode conductive adhesive layer is coated on at least one side surface of the negative electrode current collector film, with a second dividing line as the coating boundary, over the entire area of ​​the negative electrode body region.

[0416] Increasing the coverage area of ​​the conductive adhesive layer is also more conducive to improving the adhesion and conductivity between the current collector layer and the electrode active material layer, which is beneficial to further improving the cycle performance of solid-state batteries.

[0417] In some embodiments, the method for fabricating solid-state batteries satisfies one or more of the following characteristics:

[0418] In a positive electrode sheet including a positive tab, in the height direction of the positive electrode sheet, the extension height of the positive tab in the positive electrode sheet is greater than the height of the corresponding positive tab groove in the positive electrode sheet.

[0419] In a negative electrode sheet including a negative tab, in the height direction of the negative electrode sheet, the extension height of the negative tab in the negative electrode sheet is greater than the height of the corresponding negative tab groove in the negative electrode sheet.

[0420] By reserving a certain extension height for the positive or negative tab, it is easy to use it as a soft tab to be transferred to a hard tab in subsequent processes.

[0421] In some embodiments, the method for fabricating solid-state batteries satisfies one or more of the following characteristics:

[0422] In the prepared solid-state battery cell, at least a portion of the positive electrode tab has a bent section within the first composite groove;

[0423] In the prepared solid-state battery cell, at least a portion of the negative electrode tabs have a bent section within the second composite groove.

[0424] At least a portion of the tab can be bent into the corresponding composite groove, which can significantly improve the volumetric energy density of solid-state cells and solid-state batteries.

[0425] In some embodiments, the method for fabricating solid-state batteries satisfies one or more of the following characteristics:

[0426] In a positive electrode sheet including a positive tab, the width of the positive tab is smaller than the width of the corresponding positive tab groove in the width direction of the positive electrode sheet;

[0427] In a negative electrode sheet including a negative electrode tab, the width of the negative electrode tab is smaller than the width of the corresponding negative electrode tab groove in the width direction of the negative electrode sheet.

[0428] In some embodiments, the method for fabricating solid-state batteries satisfies one or more of the following characteristics:

[0429] In a positive electrode sheet including a positive electrode tab, there is a gap between the positive electrode tab and the two side edges of the positive electrode tab groove in the width direction of the positive electrode sheet;

[0430] In the negative electrode sheet including the negative electrode tab, there is a gap between the negative electrode tab and the two side edges of the negative electrode tab groove in the width direction of the negative electrode sheet.

[0431] By leaving a certain gap on both sides of the corresponding electrode at the electrode groove, a suitable space for movement can be reserved for the positive and negative electrodes, and it also allows the positive and negative electrodes to be bent into the corresponding composite groove more easily.

[0432] In some implementations, the required number of positive electrode plates is multiple; the required number of negative electrode plates matches the required number of positive electrode plates.

[0433] When there are multiple positive electrode plates used in assembling solid-state cells, there are correspondingly multiple negative electrode plates. At this time, the stacked structure corresponds to a multi-layer stacked structure. By utilizing the aforementioned cell active extension region structure design, it is beneficial to gain more volumetric energy density in the tab space.

[0434] In some implementations, multiple positive electrode plates include positive tabs; multiple negative electrode plates include negative tabs.

[0435] When multiple positive electrode plates include positive tabs and multiple negative electrode plates include negative tabs, it is more beneficial to save the waste of internal space caused by the stacking of multiple tabs.

[0436] In some embodiments, the method for preparing a solid-state battery cell may further include step S800: attaching a hard tab.

[0437] Without limitation, the hard electrode tabs may be transferred in the following ways: welding multiple positive electrode tabs on the positive electrode tab to form a positive electrode soft tab, and then transferring an aluminum hard electrode tab; welding multiple negative electrode tabs on the negative electrode tab to form a negative electrode soft tab, and then transferring a nickel hard electrode tab.

[0438] In some embodiments, the solid-state battery cell prepared is the solid-state battery cell described in the first aspect of this application.

[0439] In a third aspect of this application, a solid-state battery is provided, comprising at least one of the solid-state cells described in the first aspect of this application and solid-state cells prepared by the method for preparing solid-state cells described in the second aspect of this application.

[0440] In some implementations, the solid-state battery is an all-solid-state battery.

[0441] In this application, unless otherwise specified, "all-solid-state battery" refers to a solid-state battery in which all electrolytes are solid electrolytes. In this case, the positive electrode layer, negative electrode layer and electrolyte part are all made of solid materials, and no liquid electrolyte is provided in the battery, so it can be called "all-solid-state battery".

[0442] Solid-state batteries, including the aforementioned solid-state cells, increase the volume of the electrode body at the tab height, thereby improving the space occupancy of the electrode active material layer and significantly increasing the volumetric energy density. Furthermore, the conductive adhesive layer enhances the adhesion and conductivity between the electrode active material layer and the current collector layer, facilitating the formation of neatly edged tab grooves during die-cutting. This reduces powder shedding from the electrode active material, improves the cycle performance of the solid-state battery, and also helps reduce the risk of internal short circuits, thus improving battery reliability and production yield.

[0443] The following is a description of the positive electrode layer and the positive electrode sheet.

[0444] The positive electrode layer in a solid-state battery cell can be provided by one or more of a positive electrode sheet including a conductive adhesive layer and a positive electrode sheet not including a conductive adhesive layer. In some exemplary solid-state battery cells, at least one positive electrode layer includes a conductive adhesive layer. Unless otherwise specified, the conductive adhesive layer in the positive electrode layer may be referred to as the positive electrode conductive adhesive layer.

[0445] The positive electrode sheet including the conductive adhesive layer can be provided by the positive electrode sheet in the second aspect of this application.

[0446] For positive electrode sheets without a conductive adhesive layer, they can be prepared using either dry or wet methods. For example, a dry pressing method can be used to form a film. Alternatively, a wet coating and drying method can be employed to form a film.

[0447] In some embodiments, the positive electrode sheet includes at least a positive current collector and a layer of positive active material disposed on at least one surface of the positive current collector.

[0448] In another aspect of this application, a positive electrode sheet including a conductive adhesive layer is provided, comprising a positive current collector layer and a positive active material layer located on at least one side of the positive current collector layer; at at least one edge in the height direction of the positive electrode sheet, the positive electrode sheet is provided with a positive tab groove and a first empty groove; at least one positive electrode sheet further includes a positive tab connected to the positive current collector layer and a conductive adhesive layer located between the positive current collector layer and the positive active material layer, the conductive adhesive layer being referred to as the positive conductive adhesive layer, the positive tab being connected to the bottom of the positive tab groove of the corresponding positive electrode sheet, and the positive conductive adhesive layer at least covering the die-cut edge region of the positive tab groove. See also the context of this application.

[0449] Unless otherwise stated in this application, the positive electrode sheet includes at least a positive active material layer.

[0450] In this application, unless otherwise specified, the positive electrode active material layer includes at least positive electrode active particles, and usually also includes positive electrode electrolyte particles.

[0451] In this application, unless otherwise specified, "positive electrode active particles" refers to particles containing positive electrode active substances that have the ability to reversibly extract and insert active ions.

[0452] In this application, unless otherwise specified, "positive electrode electrolyte particles" and "positive electrode solid electrolyte" have the same meaning and can be used interchangeably, referring to solid electrolytes that can be used in the positive electrode layer. Positive electrode electrolyte particles can enhance the ion conductivity of the positive electrode layer, reduce interfacial impedance, and promote the charge transfer efficiency and full release of capacity between the positive electrode active material and the external environment.

[0453] In some embodiments, the positive electrode active material may be a known positive electrode active material for batteries. As a non-limiting example, the positive electrode active material may include one or more of the following materials: lithium-containing phosphates with an olivine structure, lithium transition metal oxides, and their respective modified compounds. However, this application is not limited to these materials, and other conventional materials that can be used as positive electrode active materials for batteries may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium transition metal oxides include, but are not limited to, one or more of lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, and their modified compounds. Non-limiting examples of lithium-containing phosphates with an olivine structure include, but are not limited to, one or more of lithium iron phosphate, lithium iron phosphate and carbon composites, lithium manganese phosphate, lithium manganese phosphate and carbon composites, lithium iron manganese phosphate, and lithium manganese iron phosphate and carbon composites. Non-limiting examples of lithium cobalt oxides may include LiCoO2; non-limiting examples of lithium nickel oxides may include LiNiO2; non-limiting examples of lithium manganese oxides may include LiMnO2, LiMn2O4, etc.; non-limiting examples of lithium nickel cobalt manganese oxides may include LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also known as NCM) 333 LiNi 0.5 Co 0.2 Mn 0.3 O2 (also known as NCM) 523 LiNi 0.5 Co 0.25 Mn 0.25 O2 (also known as NCM) 211 LiNi 0.6 Co 0.2 Mn 0.2 O2 (also known as NCM) 622 LiNi 0.8 Co 0.1 Mn 0.1 O2 (also known as NCM) 811 Examples of lithium nickel cobalt aluminum oxides include LiNi, etc. 0.80 Co 0.15 Al 0.05 O2. Examples of lithium iron phosphate include LiFePO4 (also known as LFP). Examples of lithium manganese phosphate include LiMnPO4.

[0454] Without limitation, the weight percentage of positive electrode active particles or positive electrode active materials in the positive electrode active material layer can be ≥70wt%, further ≥80wt%, even further ≥90wt%, and can also be 70wt% to 99wt%, optionally 80wt% to 95wt%.

[0455] Non-limiting, the weight percentage of the positive electrode electrolyte particles in the positive electrode active material layer can be 0.1 wt% to 30 wt%, and optionally 5 wt% to 20 wt%.

[0456] In some embodiments, the positive electrode active material layer includes positive electrode electrolyte particles. Non-limitingly, the weight percentage of the positive electrode electrolyte particles in the positive electrode active material layer can be from 0.1 wt% to 30 wt%, optionally from 5 wt% to 20 wt%.

[0457] In some embodiments, the positive electrode active material layer includes positive electrode active particles and positive electrode electrolyte particles.

[0458] In some embodiments, the positive electrode active material layer includes a conductive agent (which may be referred to as a positive electrode conductive agent). As a non-limiting example, the positive electrode conductive agent may be a carbon conductive agent. Non-limitingly, the carbon conductive agent may include one or more of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers. In some embodiments, the positive electrode conductive agent may include, but is not limited to, one or more of SP, KS-6, acetylene black, branched Ketjen black ECP, SFG-6, vapor-grown carbon fiber VGCF, carbon nanotubes (CNTs), and graphene. Non-limitingly, the weight percentage of the positive electrode conductive agent in the positive electrode active material layer may be 0–10 wt%, more further 0–8 wt%, even further 0–5 wt%, and even further 0.1 wt%–3 wt%, based on the total weight of the positive electrode active material layer. When the positive electrode material is prepared into a positive electrode active material layer using a dry method, the positive electrode conductive agent can be incorporated into the positive electrode material, which can improve the conductivity of the positive electrode active material layer.

[0459] In some embodiments, the positive electrode active material layer optionally includes a binder (which may be referred to as a positive electrode binder). As a non-limiting example, the positive electrode binder may include one or more of polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), a terpolymer of PVDF-tetrafluoroethylene-propylene, a terpolymer of PVDF-hexafluoropropylene-tetrafluoroethylene, a tetrafluoroethylene-hexafluoropropylene copolymer, and fluorinated acrylate resins. Typically, the weight percentage of the positive electrode binder in the positive electrode active material layer can be 0–10 wt%, more commonly 0–8 wt%, even more commonly 0.1 wt%–5 wt%, and even more commonly 1 wt%–5 wt%, based on the total weight of the positive electrode active material layer. When the positive electrode material is formulated into a positive electrode slurry using a wet process and then the positive electrode active material layer is prepared, the positive electrode binder can be incorporated into the positive electrode slurry, which can assist in film formation and also promote the formation of a good electrical contact network between the active particles in the positive electrode active material layer.

[0460] Non-limiting, the positive electrode active material layer may include positive electrode active particles, positive electrode electrolyte particles, positive electrode conductive agent, and positive electrode binder. The types and contents of each component can be found in the context of this application.

[0461] As a non-limiting example, the positive current collector has two surfaces that are opposite to each other in its own thickness direction, and the positive active material layer is disposed on either or both of the two opposite surfaces of the positive current collector.

[0462] In some embodiments, the positive electrode current collector may be a metal foil or a composite current collector. For example, aluminum foil may be used as the metal foil. In the positive electrode current collector, the composite current collector may include a polymer material substrate and a metal layer formed on at least one surface of the polymer material substrate. In the positive electrode current collector, the composite current collector may be obtained by forming a metal material on the polymer material substrate. Non-limiting examples of the metal material in the positive electrode current collector may include at least one of aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy. Non-limiting examples of the polymer material substrate in the positive electrode current collector may include one or more of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), and polyethylene (PE).

[0463] In some embodiments, a positive electrode sheet excluding a conductive adhesive layer can be prepared by: dry mixing the components used to prepare the positive electrode sheet, such as positive electrode active particles, positive electrode electrolyte particles, positive electrode conductive agent, positive electrode binder, and any other components; then heating and pressurizing the mixed material to knead it into a clump; hot rolling is then performed to form a self-supporting positive electrode sheet; the self-supporting positive electrode sheet is then hot-rolled and bonded to a positive electrode current collector, wherein the self-supporting positive electrode sheet can be bonded to at least one side (single or double sides) of the positive electrode current collector to obtain the positive electrode sheet. Non-limitingly, a dual planetary mixer can be used for dry mixing. Non-limitingly, a kneading and heating process can be performed using a Banbury mixer. Non-limitingly, the temperature for hot rolling can be 75°C to 85°C, and further, such as 78°C, 80°C, 82°C, etc. The method for assembling solid-state batteries using positive electrode sheets is suitable for industrial mass production.

[0464] In some embodiments, a positive electrode sheet excluding a conductive adhesive layer can be prepared by dispersing the components used to prepare the positive electrode sheet, such as positive electrode active particles, positive electrode electrolyte particles, positive electrode conductive agent, positive electrode binder, and any other components, in an organic solvent to form a positive electrode slurry. Further, the positive electrode slurry is coated onto at least one surface of a positive electrode current collector, and after drying, cold pressing, and other processes, a positive electrode sheet is obtained. Cold pressing can be performed using a cold rolling mill. The organic solvent in the positive electrode slurry can include one or more of p-xylene, trimethylbenzene, butyl butyrate, heptane, etc., and more specifically, p-xylene. The surface of the positive electrode current collector coated with the positive electrode slurry can be a single surface of the positive electrode current collector or both surfaces of the positive electrode current collector. The solid content of the positive electrode slurry can be 40wt% to 80wt%. The viscosity of the positive electrode slurry at room temperature can be adjusted to 5000 mPa·s to 25000 mPa·s. When coating the positive electrode slurry, the coating density per unit area, measured by dry weight (excluding solvent), can be 15 mg / cm³, based on the amount coated on one side of the positive electrode current collector. 2 ~35mg / cm 2 However, this is not the only possibility. The compaction density of the positive electrode sheet can be 3.0 g / cm³. 3 ~3.6g / cm 3 3.3g / cm³ is an option. 3 ~3.5g / cm 3 .

[0465] The term "compacted density" as used in this application has a meaning known in the art and is one of the reference indicators for material energy density. In this application, unless otherwise specified, the compacted density of an electrode layer refers to the ratio of the mass of the electrode active material layer to its volume. The compacted density of the positive electrode layer or positive electrode sheet refers to the ratio of the mass of the positive electrode active material layer to its volume, and the compacted density of the negative electrode layer or negative electrode sheet refers to the ratio of the mass of the negative electrode active material layer to its volume.

[0466] The composition of the positive electrode active material layer in a positive electrode sheet including the conductive adhesive layer can be found in the preparation of non-solvent components for the positive electrode active material layer in a positive electrode sheet excluding the conductive adhesive layer, but is not limited thereto.

[0467] The following is a description of the negative electrode layer and the negative electrode sheet.

[0468] The negative electrode layer in a solid-state battery cell can be provided by one or more of a negative electrode sheet including a conductive adhesive layer and a negative electrode sheet not including a conductive adhesive layer. In some exemplary solid-state battery cells, at least one negative electrode layer includes a conductive adhesive layer. Unless otherwise specified, the conductive adhesive layer in the negative electrode layer may be referred to as the negative electrode conductive adhesive layer.

[0469] The negative electrode sheet including the conductive adhesive layer can be provided by the negative electrode sheet in the second aspect of this application.

[0470] In another aspect of this application, a negative electrode sheet is provided, comprising a negative electrode current collector layer and a negative electrode active material layer located on at least one side of the negative electrode current collector layer; at at least one edge in the height direction of the negative electrode sheet, the negative electrode sheet is provided with a negative electrode tab groove and a second empty groove; at least one negative electrode sheet further comprises a negative electrode tab connected to the negative electrode current collector layer and a conductive adhesive layer located between the negative electrode current collector layer and the negative electrode active material layer, the conductive adhesive layer being referred to as the negative electrode conductive adhesive layer, the negative electrode tab being connected to the bottom of the negative electrode tab groove of the corresponding negative electrode sheet, and the negative electrode conductive adhesive layer at least covering the die-cut edge area of ​​the negative electrode tab groove.

[0471] For positive and negative electrode sheets without a conductive adhesive layer, they can be prepared using either dry or wet methods. For example, a dry pressing method can be used to form a film. Alternatively, a wet coating method can be used to form a film.

[0472] Unless otherwise stated in this application, the negative electrode sheet includes at least a negative electrode active material layer.

[0473] Unless otherwise stated in this application, the negative electrode active material layer includes at least negative electrode active particles.

[0474] In this application, unless otherwise specified, "negative electrode active particles" refers to particles containing negative electrode active substances that have the ability to reversibly insert and extract active ions.

[0475] In some embodiments, the negative electrode sheet includes a negative electrode active material layer, the negative electrode active material layer includes negative electrode active particles, and the negative electrode active particles contain negative electrode active substances.

[0476] Without limitation, the weight percentage of negative electrode active particles or negative electrode active materials in the negative electrode active material layer can be ≥80wt%, and more preferably ≥90wt%.

[0477] In some embodiments, the negative electrode active material may also be a negative electrode active material known in the art for use in solid-state batteries. As a non-limiting example, the negative electrode active material may include one or more of the following materials: elemental silicon, elemental tin, silicon-carbon anode (silicon-carbon anode material), silicon suboxide, graphite, metallic lithium, etc. However, this application is not limited to these materials or substances, and other conventional materials that can be used as battery negative electrode active materials may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0478] In some embodiments, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material layer disposed on at least one surface of the negative electrode current collector, the negative electrode active material layer comprising a negative electrode active substance. As a non-limiting example, the negative electrode current collector has two surfaces opposite to each other in its own thickness direction, and the negative electrode active material layer is disposed on either or both of the two opposite surfaces of the negative electrode current collector. In some embodiments, the negative electrode current collector may be a metal foil or a composite current collector. For example, copper foil may be used as the metal foil. In the negative electrode current collector, the composite current collector may include a polymer material base layer and a metal layer formed on at least one surface of the polymer material base layer. In the negative electrode current collector, the composite current collector may be formed by forming a metal material on the polymer material base layer. Non-limiting examples of the metal material in the negative electrode current collector may include one or more of copper, copper alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys. In the negative electrode current collector, non-limiting examples of the polymeric material substrate may include one or more of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), etc.

[0479] In some embodiments, the negative electrode active material layer optionally includes a conductive agent (which may be referred to as a negative electrode conductive agent). Non-limitingly, the negative electrode conductive agent may include one or more of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers. Non-limitingly, the weight percentage of the negative electrode conductive agent in the negative electrode active material layer may be 0–15 wt%, more preferably 0–10 wt%, and even more preferably 0–5 wt%.

[0480] In some embodiments, the negative electrode active material layer optionally includes a binder (denoted as negative electrode binder). As a non-limiting example, the negative electrode binder may include one or more of styrene-butadiene rubber (SBR), polyacrylic acid (PAA), sodium polyacrylate (PAAS), polyacrylamide (PAM), polyvinyl alcohol (PVA), sodium alginate (SA), polymethacrylic acid (PMAA), and carboxymethyl chitosan (CMCS). Non-limitingly, the weight percentage of the negative electrode binder in the negative electrode active material layer may be 0–10 wt%, more preferably 0–5 wt%, even more preferably 1 wt%–5 wt%, and even more preferably 1 wt%–3 wt%.

[0481] In some embodiments, the negative electrode active material layer may optionally include other additives, such as thickeners (e.g., sodium carboxymethyl cellulose (CMC-Na)). The weight percentage of the other additives in the negative electrode active material layer may be 0–15 wt%, more preferably 0–10 wt%, even more preferably 0–5 wt%, even more preferably 0–3 wt%, and even more preferably 0–2 wt%.

[0482] In some embodiments, a negative electrode sheet excluding a conductive adhesive layer can be prepared by dispersing the components used to prepare the negative electrode sheet, such as negative electrode active particles, negative electrode conductive agent, negative electrode binder, and any other components, in a solvent (a non-limiting example of a solvent is N-methylpyrrolidone (NMP)) to form a negative electrode slurry. Further, the negative electrode slurry is coated onto at least one surface of a negative electrode current collector, and after drying, cold pressing, and other processes, a negative electrode sheet is obtained. Cold pressing can be performed using a cold rolling mill. The surface of the negative electrode current collector coated with the negative electrode slurry can be a single surface of the negative electrode current collector or both surfaces of the negative electrode current collector. The solid content of the negative electrode slurry can be 30wt% to 70wt%, optionally 40wt% to 60wt%. The viscosity of the negative electrode slurry at room temperature can be adjusted to 2000 mPa·s to 10000 mPa·s, optionally 3000 mPa·s to 10000 mPa·s. When coating the negative electrode slurry, the coating density per unit area, based on the amount coated on one side of the negative electrode current collector and calculated by dry weight (excluding solvent), can be 1.5 mg / cm³. 2 ~22mg / cm 2 However, this is not the only possibility. The compaction density of the negative electrode sheet can be 1.0 g / cm³. 3 ~2.0g / cm 3 1.0g / cm can be selected. 3 ~1.8g / cm 3 .

[0483] The composition of the negative electrode active material layer in the negative electrode sheet including the conductive adhesive layer can be found in the preparation of the non-solvent components of the negative electrode active material layer in the negative electrode sheet excluding the conductive adhesive layer, but is not limited thereto.

[0484] The following is a description of the solid electrolyte section and the solid electrolyte layer.

[0485] The definition of a solid electrolyte section can be found above. A solid electrolyte section includes at least one solid electrolyte layer.

[0486] The solid electrolyte layer acts as a conductor of ions between the positive and negative electrode layers, and can also isolate the positive and negative electrode layers to prevent short circuits between them.

[0487] It is understood that the solid electrolyte layer includes a solid electrolyte. The solid electrolyte in the solid electrolyte layer can be a solid electrolyte known in the art that can be used in solid-state batteries.

[0488] The types of solid electrolytes present in different film layers of a solid-state battery can be the same or different. For example, the solid electrolytes in the positive electrode electrolyte particles and the solid electrolyte layer can be the same or different.

[0489] As a non-limiting example, a solid electrolyte may independently include one or more of the following materials: sulfide solid electrolytes, halide solid electrolytes, oxide solid electrolytes, polymer solid electrolytes, etc.

[0490] As another non-limiting example, the solid electrolyte may independently include, but is not limited to, one or more of oxide-based solid electrolytes, sulfide-based solid electrolytes, and halide-based solid electrolytes. In some embodiments, the solid electrolyte may independently include, but is not limited to, one or more of Argyrodite-type sulfide electrolytes and halide electrolytes. Non-limiting examples of oxide-based solid electrolytes may include LISICON-type oxide electrolytes (such as γ-Li3PO4), NASICON-type oxide electrolytes (such as Li... 1+x Al x Ge 2-x (PO4)3,Li 1+x Al x Ti 2-x (PO4)3, etc., 0≤x≤1), Garnet type (such as Li7La3Zr2O) 12 (etc.), perovskite-type oxide electrolytes (such as Li, etc.) 3x La 2 / 3-x One or more of the following: TiO3, etc., 0≤x≤0.5, etc. Non-limiting examples of sulfide solid electrolytes may include Li...10 GeP2S 12 Li₂S-P₂S₅, Argyrodite type (such as Li₆PS₅Cl, Li 5.5 PS 5.5 Cl 1.5 One or more of the following (etc.). Non-limiting examples of halide solid electrolytes may include one or more of the following: Li3InCl6, Li3YCl6, Li3ScCl6, Li3ErCl6, Li2ZrCl6, etc.

[0491] In some embodiments, a solid electrolyte material can be pressed into a solid electrolyte membrane to provide a solid electrolyte layer.

[0492] In some embodiments, the thickness of the solid electrolyte layer can be 0.1 μm to 1000 μm, and can be selected from thickness ranges such as 10 μm to 100 μm, 100 μm to 800 μm, and 500 μm to 800 μm.

[0493] Non-limitingly, a solid-state battery cell can be prepared by sequentially stacking a positive electrode, a solid electrolyte membrane, and a negative electrode, with the solid electrolyte membrane placed between the positive and negative electrodes, and then rolling. The rolling process can be either cold rolling or hot rolling. A non-limiting example of a hot rolling temperature is 180°C.

[0494] A solid-state battery includes at least one solid-state battery cell. A solid-state battery may include one or more solid-state battery cells.

[0495] In this application, unless otherwise specified, "solid-state battery cell" refers to a basic unit capable of converting chemical energy into electrical energy, and all its components are solid-state. In some embodiments, a solid-state battery cell may be an all-solid-state battery cell.

[0496] In this application, unless otherwise specified, "all-solid-state battery cell" refers to a solid-state battery cell in which all electrolytes are solid electrolytes. In this case, the positive electrode layer, negative electrode layer and electrolyte part are all made of solid materials, and no liquid electrolyte is provided in the battery cell, so it can be called "all-solid-state battery cell".

[0497] Non-limitingly, a solid-state battery cell (which can be an all-solid-state battery cell) may include a positive electrode layer, a solid electrolyte layer, and a negative electrode layer, with the solid electrolyte layer located between the positive and negative electrode layers. During battery charging and discharging, active ions shuttle between the positive and negative electrode layers, inserting and extracting. The solid electrolyte layer serves to conduct ions between the positive and negative electrode layers and also isolates them, thus preventing short circuits between the positive and negative electrodes.

[0498] In some embodiments, the solid-state battery cell 5 includes a solid-state cell 52.

[0499] In some implementations, the solid-state cell is an all-solid-state cell.

[0500] In some embodiments, the solid-state cell 52 (which may be an all-solid-state cell) includes a positive electrode layer, a solid electrolyte layer, and a negative electrode layer stacked sequentially.

[0501] Unless otherwise stated, solid-state cells meet at least one of the following characteristics:

[0502] The positive electrode layer with at least one layer includes the positive electrode sheet with a conductive adhesive layer as described in the second aspect of this application;

[0503] The negative electrode layer with at least one layer includes the negative electrode sheet with a conductive adhesive layer as described in the second aspect of this application.

[0504] In some embodiments, the solid-state battery may include an outer packaging. This outer packaging can be used to encapsulate the aforementioned solid-state battery cell.

[0505] In some embodiments, the outer packaging of a solid-state battery can be a rigid shell, such as a hard plastic shell, an aluminum shell, or a steel shell. The outer packaging of a solid-state battery can also be a soft pack, such as a pouch-type soft pack. The material of the soft pack can be plastic; further, non-limiting examples of plastics may include one or more of polypropylene, polybutylene terephthalate, and polybutylene succinate.

[0506] This application does not impose any particular limitation on the shape of the solid-state battery cell; it can be cylindrical, square, or any other arbitrary shape. For example, Figure 5 shows a square solid-state battery cell 5 as an example.

[0507] In some embodiments, referring to FIG6, the outer packaging may include a housing 51 and a cover plate 53. The housing 51 may include a base plate and side plates connected to the base plate, the base plate and side plates forming a receiving cavity. The housing 51 has an opening communicating with the receiving cavity, and the cover plate 53 can be placed over the opening to close the receiving cavity. A solid-state battery cell 52 is encapsulated within the receiving cavity. The number of solid-state battery cells 52 contained in the solid-state battery cell 5 may be one or more, which can be selected by those skilled in the art according to actual needs.

[0508] The solid-state battery can be either battery module 4 or battery pack 1.

[0509] The battery module includes at least one solid-state battery cell. The battery module may contain one or more solid-state battery cells, and those skilled in the art can select an appropriate number based on the application and capacity of the battery module.

[0510] Figure 7 shows a battery module 4 as an example. Referring to Figure 7, in the battery module 4, multiple solid-state battery cells 5 can be arranged sequentially along the length of the battery module 4. Of course, they can also be arranged in any other manner. Furthermore, the multiple solid-state battery cells 5 can be fixed in place using fasteners.

[0511] Optionally, the battery module 4 may also include a housing with a receiving space in which multiple solid-state battery cells 5 are housed.

[0512] In some embodiments, the battery modules described above can also be assembled into a battery pack, and the battery pack may contain one or more battery modules. Those skilled in the art can select an appropriate number based on the application and capacity of the battery pack.

[0513] Figures 8 and 9 illustrate a battery pack 1 as an example. Referring to Figures 8 and 9, the battery pack 1 may include a battery compartment and multiple battery modules 4 disposed within the battery compartment. The battery compartment includes an upper compartment 2 and a lower compartment 3, with the upper compartment 2 covering the lower compartment 3 to form a closed space for accommodating the battery modules 4. The multiple battery modules 4 can be arranged in any manner within the battery compartment.

[0514] In a fourth aspect of this application, an electrical device is provided, comprising at least one of the solid-state battery cell described in the first aspect of this application, a solid-state battery cell prepared by the method for preparing a solid-state battery cell described in the second aspect of this application, and a solid-state battery described in the third aspect of this application.

[0515] In some embodiments, the electrical device includes at least one of the solid-state batteries of the various embodiments provided in this application.

[0516] In a non-limiting sense, solid-state batteries can be used as a power source for electrical devices or as an energy storage unit for electrical devices. Electrical devices can include, but are not limited to, mobile devices, electric vehicles, electric trains, ships and satellites, energy storage systems, etc. Mobile devices can be, for example, mobile phones, laptops, etc.; electric vehicles can be, for example, pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric bicycles, electric scooters, electric golf carts, electric trucks, electric motorcycles, power tools, etc., but are not limited to these. This electrical device can also be applied to military equipment, aerospace, and other fields, and can also be applied to energy storage power systems such as hydroelectric, thermal, wind, and solar power plants.

[0517] As an electrical device, solid-state batteries can be selected based on its usage requirements.

[0518] Figure 10 shows an example of an electrical device 6. This electrical device is a pure electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle, etc. To meet the high power and high energy density requirements of this electrical device for solid-state batteries, a battery pack or battery module can be used.

[0519] Another example device could be a mobile phone, tablet, or laptop. These devices typically require a thin and light design and can use solid-state batteries as their power source.

[0520] The following describes some embodiments of this application. The embodiments described below are exemplary and are only used to explain this application, and should not be construed as limiting this application. Where the technology or conditions are not specified in the embodiments, they are performed according to the description above, or according to the technology or conditions described in the literature in this field, or according to the product instructions. Reagents or instruments whose manufacturers are not specified are all conventional products that can be obtained commercially, or can be synthesized from commercially available products using conventional methods.

[0521] In the following examples, room temperature refers to 20°C to 30°C.

[0522] In the following examples, the solid electrolyte layer, solid electrolyte membrane, positive electrode current collector membrane, positive electrode conductive adhesive layer, positive electrode active pre-coating layer, positive electrode active material layer, positive electrode current collector layer, positive electrode sheet, negative electrode current collector membrane, negative electrode conductive adhesive layer, negative electrode active pre-coating layer, negative electrode active material layer, negative electrode current collector layer, and negative electrode sheet: their width direction is consistent with the width direction (X direction) of the solid-state battery cell, their height direction is consistent with the height direction (Y direction) of the solid-state battery cell, and their thickness direction is consistent with the thickness direction (Z direction) of the solid-state battery cell.

[0523] In the following examples, the positive or negative electrode sheet has a tab groove, a corresponding tab, and a reserved empty groove on the same side edge in the electrode height direction. Correspondingly, a positive tab and a negative tab are provided on the same side in the solid-state cell height direction. In other embodiments, when the positive and negative tabs are located on different sides in the solid-state cell height direction, the utilization rate ψ of the cell's active extension region in the Y direction is... Y and the two-dimensional utilization rate ψ of the cell's active extension region A It will be higher.

[0524] In the following examples, as non-limiting examples, the positive electrode tab groove, the second empty groove, the fourth empty groove, and the first composite groove have the same shape and size in the X and Y directions; the negative electrode tab groove, the first empty groove, the third empty groove, and the second composite groove have the same shape and size in the X and Y directions; and the dimensions of the positive electrode tab groove and the negative electrode tab groove are also substantially the same in the X and Y directions. For each of the above grooves, the groove depth is equal to the groove height, the groove width direction is consistent with the X direction, the groove height or depth direction is consistent with the Y direction, and the groove thickness direction is consistent with the Z direction.

[0525] In the following examples, during the preparation of the positive and negative electrode sheets, after die-cutting, the width of the positive electrode tab and the width of the negative electrode tab are slightly smaller than the width of the corresponding groove. That is, in the electrode sheet width direction, gaps are provided between the positive and negative electrode tabs and the two sides of the corresponding electrode tab groove, with each gap ranging from 10μm to 5000μm and from 0.1mm to 1mm. Correspondingly, in the solid-state battery cell, gaps are provided between the positive and negative electrode tabs and the two sides of the corresponding composite groove, with each gap ranging from 10μm to 5000μm and from 0.1mm to 1mm.

[0526] In the following examples, as non-limiting examples, the height of both the positive and negative tabs is set to 15 mm.

[0527] In the following examples, solid-state cells with a stacked structure are used as non-limiting examples.

[0528] In the following examples, a hot melt dispensing machine (ET-420D, Easy Vision) was used to dispense adhesive at 180°C to add a conductive adhesive layer to the positive current collector film aluminum foil or the negative current collector film copper foil.

[0529] Unless otherwise specified, the following examples use the following method for counting "approximations" in micrometers (μm) or nanometers (nm): for values ​​accurate to one decimal place, the fluctuation range is within ±0.05; for values ​​accurate to one unit place between 1 and 9, the fluctuation range is within ±0.2; for values ​​accurate to one unit place between 10 and 99, the fluctuation range is within ±0.5.

[0530] I. Preparation of adhesive for conductive adhesive layer

[0531] In Example A1, polypropylene (PP, weight average molecular weight approximately 1300 kDa), maleic anhydride (MAH), styrene-ethylene-butene-styrene block copolymer (SEBS, weight average molecular weight approximately 600 kDa), and petroleum resin (C5) were reacted in a reactor at 160°C under vacuum for 120 min at a weight ratio of 20:4:10:10 to obtain maleic anhydride-modified polypropylene resin (belonging to the aforementioned polyolefin-modified resin). Maleic anhydride-modified polypropylene resin, paraffin wax, antioxidant (thanox1726, Tianjin Lialong), anti-aging agent (Tinuvin326, BASF), and carbon conductive graphene were mixed at a mass ratio of 50:5:0.2:0.2:50, stirred at 1200 rpm for approximately 60 min, and then stirred at 800 rpm for approximately 30 min to obtain a rubber compound.

[0532] II. Solid-state battery preparation methods

[0533] The positive and negative electrode sheets are prepared by referring to the structures shown in Figures 2, 3 and 4.

[0534] Example A1.

[0535] 1. Preparation of positive electrode sheet.

[0536] On the surface of the positive electrode current collector membrane 111, the positive electrode body region 1112 and the positive electrode inactive region 1110, which are adjacent to each other by a first boundary line 1000, are identified. The first boundary line 1000 extends along the width direction of the positive electrode current collector membrane 111 in a concave shape, such that the positive electrode inactive region 1110 includes a positive electrode tab concave region 1220 and a first concave region 1240 that are concave towards the positive electrode body region 1112, and the positive electrode tab concave region 1220 and the first concave region 1240 are separated by the positive electrode body region 1112; wherein, the positive electrode tab concave region 1220 is matched with the positive electrode tab groove 122, and the first concave region 1240 is matched with the first empty groove 124.

[0537] On both sides of the positive electrode current collector film 111, a conductive adhesive layer (denoted as positive electrode conductive adhesive layer 120) is added to the positive electrode body region 1112 with the first dividing line 1000 as the coating boundary. The thickness of the conductive adhesive layer can be referred to in Table 2. The adhesive of the positive electrode conductive adhesive layer is applied to the selected area using a hot melt dispensing machine (ET-420D), and then cooled and cured to form the conductive adhesive layer.

[0538] On both sides of the positive electrode current collector film 111 with the positive electrode conductive adhesive layer 120 attached, the positive electrode self-supporting sheet is attached and hot rolled to form the positive electrode active pre-coating layer 1402, so that the positive electrode active pre-coating layer 1402 covers the positive electrode body region 1112, the positive electrode tab recessed region 1220 and the first recessed region 1240.

[0539] Remove the portion of the positive electrode active pre-coating 1402 covering the concave region 1220 and the first concave region 1240 of the positive electrode tab, exposing the corresponding positive electrode current collector film surface, to obtain a positive electrode die slice; wherein, the remaining portion of the positive electrode active pre-coating 1402 corresponds to the positive electrode active material layer 140, and the portion of the positive electrode current collector film covered by the positive electrode active material layer 140 corresponds to the positive electrode current collector layer 110;

[0540] Die-cutting the positive electrode sheet according to the first dividing line 1000 to form a positive electrode sheet 100; wherein, the die-cutting of the positive electrode sheet according to the first dividing line 1000 includes: die-cutting out the corresponding contour of the positive electrode active material layer 140 except for the positive electrode tab recess 1220, die-cutting out the contour of the two side edges of the positive electrode tab groove 122 and the positive electrode tab 130 connected to the positive electrode current collector layer 110 in the positive electrode tab recess 1220, and die-cutting out the first empty groove 124 in the first recess 1240 according to the first dividing line 1000.

[0541] In Example A1, the raw material composition of the positive electrode self-supporting sheet is: LiNi 0.8 Co 0.1 Mn 0.1 O2 (NCM811), sulfide solid electrolyte Li6PS5Cl, conductive agent VGCF (vapor-grown carbon fiber), and binder polytetrafluoroethylene (PTFE) are mixed in a mass ratio of 84:12.5:2:1.5.

[0542] 2. Preparation of negative electrode sheet.

[0543] On the surface of the negative electrode current collector membrane 311, the negative electrode body region 3112 and the negative electrode inactive region 3110, which are adjacent to each other by a second boundary line 3000, are identified. The second boundary line 3000 extends along the width direction of the negative electrode current collector membrane 311 in a concave shape, such that the negative electrode inactive region 3110 includes a negative electrode tab concave region 3220 and a second concave region 3240 that are concave toward the negative electrode body region 3112, and the negative electrode tab concave region 3220 and the second concave region 3240 are separated by the negative electrode body region 3112; wherein, the negative electrode tab concave region 3220 is matched with the negative electrode tab groove 322, and the second concave region 3240 is matched with the second empty groove 324.

[0544] On both sides of the negative electrode current collector film 311, a conductive adhesive layer (which can be referred to as negative electrode conductive adhesive layer 320) is added to the negative electrode body region 3112 with the second dividing line 3000 as the coating boundary. The thickness of the conductive adhesive layer can be found in Table 2. The adhesive of the negative electrode conductive adhesive layer is applied to the selected area using a hot melt dispensing machine (ET-420D), and then cooled and cured to form the conductive adhesive layer.

[0545] On both sides of the negative electrode current collector film 311 with the negative electrode conductive adhesive layer 320 attached, the negative electrode self-supporting sheet is attached and hot rolled to form the negative electrode active pre-coating layer 3402, so that the negative electrode active pre-coating layer 3402 covers the negative electrode body region 3112, the negative electrode tab recessed region 3220 and the second recessed region 3240.

[0546] Remove the portion of the negative electrode active pre-coating 3402 covering the negative electrode tab recess 3220 and the second recess 3240 to expose the corresponding negative electrode current collector film surface and obtain a negative electrode die slice; wherein, the remaining portion of the negative electrode active pre-coating 3402 corresponds to the negative electrode active material layer 340, and the portion of the negative electrode current collector film covered by the negative electrode active material layer 340 corresponds to the negative electrode current collector layer 310.

[0547] The negative electrode sheet to be die-cut is formed by die-cutting the negative electrode sheet according to the second boundary line 3000. The die-cutting process of the negative electrode sheet to be die-cut according to the second boundary line 3000 includes: die-cutting out the corresponding contour of the area of ​​the negative electrode active material layer 340 except for the negative electrode tab concave region 3220; die-cutting out the contour of the two side edges of the negative electrode tab groove 322 and the negative electrode tab 330 connected to the negative electrode current collector layer 310 in the negative electrode tab concave region 3220; and die-cutting out the second empty groove 324 in the second concave region 3240 according to the second boundary line 3000.

[0548] The negative electrode self-supporting sheet is composed of: negative electrode active particle silicon powder, sulfide solid electrolyte powder Li6PS5Cl and binder PVDF mixed in a mass ratio of 82:15:3.

[0549] 3. Preparation of solid electrolyte membranes.

[0550] Solid electrolyte membranes are die-cut using laser cutting technology to obtain solid electrolyte membrane sheets that match the shapes of the positive and negative electrode sheets. A fourth recess is reserved in the positive electrode tab 130 of the positive electrode sheet 100, and a third recess is reserved in the negative electrode tab 330 of the negative electrode sheet 300. Further, the fourth recess corresponds to the first composite recess 1302 in the solid-state cell 52 for accommodating a portion of the positive electrode tab 1300, and the third recess corresponds to the second composite recess 3302 in the solid-state cell 52 for accommodating a portion of the negative electrode tab 3300.

[0551] The preparation method of the solid electrolyte membrane is as follows: the sulfide electrolyte Li6PS5Cl powder is rolled into a film to obtain the solid electrolyte membrane.

[0552] 4. Stacking and assembly.

[0553] According to their respective required quantities, positive electrode 100, solid electrolyte membrane, and negative electrode 300 are stacked, with the positive electrode 100 and negative electrode 300 isolated by the solid electrolyte membrane. The outlines of the positive electrode tab groove 122, the fourth empty groove, and the second empty groove 324 are aligned to form a first composite groove 1302, and the outlines of the negative electrode tab groove 322, the third empty groove, and the first empty groove 124 are aligned to form a second composite groove 3302, thus obtaining a laminated part. Each positive electrode constitutes a positive electrode portion, each negative electrode constitutes a negative electrode portion, and each solid electrolyte membrane constitutes a solid electrolyte portion. Each positive electrode tab of the positive electrode portion constitutes a flexible segment of the positive electrode tab portion 1300, and at least a portion of the flexible segment of the positive electrode tab portion 1300 is accommodated in the first composite groove 1302. Each negative electrode tab of the negative electrode portion constitutes a flexible segment of the negative electrode tab portion 3300, and at least a portion of the flexible segment of the negative electrode tab portion 3300 is accommodated in the second composite groove 3302.

[0554] 5. Roll pressing process.

[0555] The laminated components are cold-pressed to form a solid battery cell.

[0556] 6. Adapter Hard Tab. Weld multiple positive tabs on the positive electrode portion to form a soft positive electrode tab, and then adapter with an aluminum hard electrode tab; weld multiple negative tabs on the negative electrode portion to form a soft negative electrode tab, and then adapter with a nickel hard electrode tab. Pre-bend the soft positive electrode tab, placing at least a portion extending beyond the first composite groove into the first composite groove; pre-bend the soft negative electrode tab, placing at least a portion extending beyond the second composite groove into the second composite groove.

[0557] 7. Aluminum-Plastic Film Encapsulation: The aluminum-plastic film is perforated and overlapped with the solid-state battery cell. The edges of the aluminum-plastic film are then sealed, encapsulating the solid-state battery cell within the housing cavity to obtain a solid-state battery. The height of the solid-state battery cell is approximately the same as the height of the housing cavity.

[0558] III. Volumetric Energy Density Analysis

[0559] Solid-state batteries are obtained using the methods described in Part II or similar methods.

[0560] (I) Implementation Examples

[0561] In Example A1, the number of positive electrode plates in the laminate is 5; multiple positive electrode layers in the solid-state battery cell together constitute the positive electrode body, and multiple negative electrode layers in the solid-state battery cell together constitute the negative electrode body. The positive electrode tab includes multiple positive electrode tabs, corresponding to the positive electrode tab laminate; the negative electrode tab includes multiple negative electrode tabs, corresponding to the negative electrode tab laminate.

[0562] Examples A2 to A16 employ essentially the same method as Example 1, except that the cell size and / or groove size are changed. See Table 1 for details.

[0563] Example A17 adopts the same method as Example 1, except that in step (4), the number of positive electrode plates in the laminate is 1, the positive electrode part includes only one positive electrode layer and one positive electrode tab, and the positive electrode tab is used as the positive electrode tab part to directly connect to the aluminum hard electrode tab; the number of negative electrode plates in the laminate is 1, the negative electrode part includes only one negative electrode layer and one negative electrode tab, and the negative electrode tab is used as the negative electrode tab part to directly connect to the nickel hard electrode tab.

[0564] Comparative examples a1 to a17: Traditional process, no active extension region.

[0565] Comparative Examples a1 to a17 are based on Examples A1 to A17, respectively, without the cell active extension region. When adding the positive electrode self-supporting sheet in the step of preparing the positive electrode sheet, the height region corresponding to the positive electrode tab groove is not covered; that is, the region corresponding to the cell active extension region of Examples A1-A17 is not provided with a positive electrode active material layer. When die-cutting the positive electrode tab, the height of the positive electrode tab remains unchanged, and the remaining areas of the positive electrode current collector membrane without a positive electrode active material layer are cut off. Similarly, when adding the negative electrode self-supporting sheet in the step of preparing the negative electrode sheet, the height region corresponding to the negative electrode tab groove is not covered; that is, the region corresponding to the cell active extension region of Examples A1-A17 is not provided with a negative electrode active material layer. When die-cutting the negative electrode tab, the height of the negative electrode tab remains unchanged, and the remaining areas of the negative electrode current collector membrane without a negative electrode active material layer are cut off.

[0566] (II) Analytical Methods

[0567] 1. The volume utilization improvement rate contributed by the active extended region of the cell to solid-state batteries.

[0568] Volume utilization improvement rate: can be estimated based on the percentage of the area of ​​the cell active extension region relative to the area of ​​the electrode active region when no cell active extension region is provided.

[0569] Based on the parameters in Table 1, the following formula can be used to calculate:

[0570] Volume utilization improvement rate = (W Δ ×H Δ ) / (W0×(H 0- H Δ ))×100%.

[0571] The analysis results can be found in Table 1.

[0572] 2. Utilization parameters of the active extension region

[0573] (1) The utilization rate of the active extension region of the cell in the Y direction (the height direction of the solid cell) can be estimated by the following formula: ψ Y =H Δ / H0×100%.

[0574] (2) The utilization rate of the active extension region of the cell in the X direction (width direction of the solid cell) can be estimated by the following formula: ψ X =W Δ / W0×100%.

[0575] (3) The two-dimensional utilization rate of the active extension region of the battery cell can be estimated using the following formula: ψ A =A Δ / A0×100%, where A0 is the projected area of ​​the solid-state cell along the Z direction (the thickness direction of the solid-state cell), and A is the projected area of ​​the cell's active extension region along the Z direction. Δ A0 = W0 × H0, A Δ =H Δ ×(W0-W Δ ).

[0576] (III) Analysis Results

[0577] Compared to comparative examples a1-a17 without an active extension region, the structural designs of examples A1-A17 can significantly improve the volume utilization rate of solid-state batteries, thereby increasing the volumetric energy density of the batteries. In examples A1-A16, taking an example where the number of positive electrode layers equals the number of positive electrode layers in the positive electrode body (e.g., 5), it is understood that those skilled in the art can replace the number of positive electrode layers with other desired numbers based on the battery thickness, achieving the same or substantially the same effect of increasing the volumetric energy density of the battery. See Example 17 for further details.

[0578] Table 1.

[0579] In Table 1, the number of positive electrode plates in Examples 1-16 is 5, and the number of positive electrode plates in Example 17 is 1.

[0580] IV. Battery Performance Testing

[0581] Example B1. Solid-state cells and solid-state batteries were prepared using the same method as in Example A17. One positive electrode was used to prepare the solid-state cell.

[0582] Examples B2 to B4. Solid-state cells and solid-state batteries were prepared using essentially the same method as in Example B1, with the main difference being the change in the amount of maleic anhydride in the polyolefin-modified resin. See Table 2 for details.

[0583] Examples B5 to B11. Solid-state cells and solid-state batteries were prepared using essentially the same method as in Example B1, with the main differences being: one or more parameters in the composition and thickness of the conductive adhesive layer were different; and one or more parameters in the type and amount of the adhesive matrix and the thickness of the conductive adhesive layer were changed. Some related parameters can be adjusted adaptively, such as the mass ratio of the adhesive matrix to the carbon conductive material. See Table 2.

[0584] Comparative Example b1. No conductive adhesive layer is set, and the active extension area of ​​the cell is retained.

[0585] Solid-state cells and solid-state batteries were prepared using the same method as in Example B1. The main difference was that no conductive adhesive layer was provided before attaching the self-supporting sheet of the electrode, and the electrode active pre-coating layer in each groove area was selectively removed during the electrode tab die-cutting stage.

[0586] Comparative Example b2. Solid-state cells and solid-state batteries were prepared using the same method as in Example B1. The main difference was that, during the preparation of the positive electrode sheet, the polyolefin-modified resin in the conductive adhesive coating was replaced with the binder PTFE in the positive electrode active material layer.

[0587] Comparative Example b3. Solid-state cells and solid-state batteries were prepared using the same method as in Example B1. The main difference was that, in the process of preparing the negative electrode sheet, the polyolefin modified resin in the conductive adhesive coating was replaced with the binder PVDF in the negative electrode active material layer.

[0588] Comparative Example b4. Using the traditional method without setting the cell active extension region: Compared to Example B1, when adding the positive self-supporting sheet in the step of preparing the positive electrode sheet, the height area corresponding to the positive electrode tab groove is not covered. That is, the area corresponding to the cell active extension region of Example B1 is not provided with a positive active material layer. When the positive electrode tab is die-cut, the height of the positive electrode tab remains unchanged, and the area of ​​the positive current collector film without a positive active material layer is cut off. When adding the negative self-supporting sheet in the step of preparing the negative electrode sheet, the height area corresponding to the negative electrode tab groove is not covered. That is, the area corresponding to the cell active extension region of Example B1 is not provided with a negative active material layer. When the negative electrode tab is die-cut, the height of the negative electrode tab remains unchanged, and the area of ​​the negative current collector film without a negative active material layer is cut off.

[0589] Test method:

[0590] (I) Materials

[0591] The weight-average molecular weight of the prepared polyolefin-modified resin was determined using a Waters 2695 Isocratic HPLC gel electrophoresis system (differential refractive index detector 2141). A 3.0 wt% polystyrene solution was used as a reference, and a matched column (oil-based: Styragel HT5 DMF7.8*300mm + Styragel HT4) was selected. A 3.0% polyolefin-modified resin solution was prepared using purified N-methylpyrrolidone (NMP) solvent and allowed to stand for one day. For testing, tetrahydrofuran was first used to flush the solution, repeated several times. Then, 5 ml of the experimental solution was drawn, air was expelled from the syringe, and the needle tip was dried. Finally, the sample solution was slowly injected into the injection port. After the reading stabilized, the data was obtained to determine the weight-average molecular weight of the polyolefin-modified resin.

[0592] (II) Electrodes and Batteries

[0593] 1. The adhesion force of the conductive adhesive layer to the current collector layer and the electrode active material layer.

[0594] Samples to be tested: positive and negative electrode sheets prepared in each embodiment.

[0595] Test method: Cut the electrode sheet into a sample 100mm long × 10mm wide and take a 25mm wide stainless steel plate; apply double-sided tape (with a width greater than 11mm) to the stainless steel plate; attach the sample to the double-sided tape and roll it back and forth three times (300mm / min) with a roller of 2000g; bend the sample 180° and manually peel 25mm apart from the electrode active material layer to the current collector layer; fix the sample on a tensile testing machine, ensuring the peel surface is aligned with the force line of the testing machine; continuously peel at 30mm / min; take the average value of the stable segment of the peel force curve as the peel force F0; then the adhesion force between the electrode active material layer and the current collector layer in the test sample is F = F0 / width of the sample (unit of F: N / m).

[0596] Higher adhesion indicates a stronger bond between the electrode active material layer and the current collector layer, resulting in a more stable electrode structure and improved cycle life of solid-state batteries. Furthermore, a lower risk of powder shedding from the electrode active material indicates better reliability of the solid-state battery.

[0597] 2. Electrode resistivity

[0598] The resistivity of the prepared positive and negative electrode sheets was measured using a membrane resistance meter, with units of Ω·m. Small circular sheets with a diameter of 3 mm were used as samples. Three samples were taken from each electrode, and two tests were conducted at each sample location. The average of the six test values ​​was calculated as the electrode resistivity test result.

[0599] The lower the resistivity of the electrode, the better the conductivity of the conductive adhesive layer, given the same current collector layer and electrode active material layer.

[0600] The resistivity test values ​​of the positive and negative electrode plates can also be regarded as the resistivity test values ​​of the electrode layers in solid-state cells.

[0601] 3. Battery internal resistance DCR

[0602] DCR Test: At 25℃, charge the battery at a constant current of 1 / 3C to 3.65V, then charge it at a constant voltage of 3.65V until the current is 0.05C. After resting for 5 minutes, discharge it at a constant current of 1 / 3C for 90 minutes, and then rest for 120 minutes. Record the voltage V1. Then discharge it at 4C for 30 seconds and record the voltage V2. The internal resistance DCR of the battery is obtained by dividing (V2-V1) / 4C.

[0603] The better the conductivity of the conductive adhesive layer, the more beneficial it is to reducing the internal resistance of the battery.

[0604] 4. Battery cycle performance

[0605] The testing process is as follows: The assembled all-solid-state battery is first activated by charging and discharging at 0.1C for 3 cycles to obtain the initial capacity C1. Then, it undergoes standard charge and discharge at 0.33C, followed by discharge at the standard charge and discharge rate to obtain the discharge capacity C2. The capacity retention rate in the second cycle is C2 / C1×100%. A long-cycle test is then performed from the 3rd to the 200th cycle. The cycle capacity retention rate for the corresponding number of cycles is calculated as Cn / C1×100%, where n is an integer from 3 to 200. The battery voltage test window is 2.8–4.3V vs. Li. + / Li (Li potential, active ion is Li) + The battery was tested at 25±3℃, where 1C=200mA / g.

[0606] The test results can be found in Table 2, "Capacity retention rate after 200 cycles, 0.33C".

[0607] 5. Volumetric energy density

[0608] The cell volume of the solid-state battery is recorded as V0.

[0609] Capacity test: Charge at a constant current of 1 / 3C to 3.65V, then charge at a constant voltage of 3.65V to a current of 0.05C, let stand for 5 minutes, and then discharge at 1 / 3C to 2.5V to obtain the capacity C0. The voltage plateau is recorded as U.

[0610] The volumetric energy density of the battery is VED = C0 × U / V0.

[0611] Test Results and Analysis:

[0612] The weight-average molecular weights of the maleic anhydride-modified polyolefin resins prepared were all in the range of 1300 kDa to 1500 kDa, of which the weight-average molecular weight of the polyolefin-modified resin in Example 1 was about 1500 kDa.

[0613] The resistivity of the prepared positive and negative electrode sheets is mostly less than 200 Ω·m, and further within the range of 10 Ω·m to 200 Ω·m.

[0614] In Examples B1 to B11, a conductive adhesive layer was incorporated into the solid-state cells and batteries, improving the adhesion and conductivity between the current collector layer and the active material layer in the electrode sheets. Compared to Comparative Example 1, the solid-state cells and batteries prepared in Examples B1 to B11 exhibited significantly improved cycle performance while achieving increased volumetric energy density. Furthermore, the internal resistance of the batteries in Examples B1-B8 also decreased to varying degrees. See Tables 2 and 3 for details.

[0615] In Comparative Examples 2-3, the adhesive matrix in the conductive adhesive layer was replaced with the binder in the electrode active material layer. The results showed that, compared with Examples B1 to B4, although the adhesion was improved in Comparative Examples 2-3, the internal resistance of the battery was significantly increased, which was due to the significant increase in interfacial impedance.

[0616] Table 2.

[0617] In Table 2, polyolefin-modified resins are used as the adhesive matrix in the corresponding conductive adhesive layers. PP represents polypropylene, and PE represents polyethylene.

[0618] Table 3. Electrode Resistivity

[0619] Furthermore, compared to Comparative Example b4, which did not have a cell active extension region, Example B1 demonstrates that the addition of a cell active extension region improves the volumetric energy density of the battery.

[0620] The descriptions of the various implementation methods and embodiments above tend to emphasize the differences between them. Similarities or resemblances can be referenced interchangeably, and for the sake of brevity, they will not be repeated here. The technical features of the implementation methods and embodiments described above can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments have been described. However, as long as the combinations of these technical features do not contradict each other, they should be considered within the scope of this specification.

[0621] It should be noted that this application is not limited to the above-described embodiments and examples. The above-described embodiments and examples are merely examples, and any embodiments and examples that have the same structure and achieve the same effect as the technical concept within the scope of this application are included in the technical scope of this application. The embodiments and examples described above only illustrate several embodiments and examples of this application, and although the descriptions are relatively detailed, they should not be construed as limiting the scope of the patent. Furthermore, various modifications that can be conceived by those skilled in the art to the embodiments or examples, and other ways of constructing embodiments or examples by combining some of the constituent elements of the embodiments or examples, are also included in the scope of this application without departing from the spirit of this application.

Claims

1. A solid-state battery cell, comprising a solid electrolyte portion and two electrode portions, one of which is a positive electrode portion and the other is a negative electrode portion, the positive electrode portion and the negative electrode portion being isolated by the solid electrolyte portion; each of the electrode portions independently includes an electrode body and a tab portion connected to the electrode body, the electrode body including at least one electrode layer, the electrode layer including a current collector layer and an electrode active material layer located on at least one side of the current collector layer; the tab portion in the positive electrode portion is a positive tab portion, and the tab portion in the negative electrode portion is a negative tab portion; The height direction of the solid-state battery cell is denoted as the Y direction, the width direction as the X direction, and the thickness direction as the Z direction; the X direction, the Y direction, and the Z direction are perpendicular to each other; At at least one edge in the Y direction, the solid-state battery cell has two composite grooves, referred to as the first composite groove and the second composite groove, respectively; the first composite groove is used to accommodate at least a portion of the positive electrode tab, and the second composite groove is used to accommodate at least a portion of the negative electrode tab; each electrode layer has grooves corresponding to the first composite groove and the second composite groove, respectively. In the at least one electrode layer, the current collector layer is connected to a tab at the bottom of at least one of the grooves, and the electrode layer further includes a conductive adhesive layer located between the current collector layer and the electrode active material layer, the conductive adhesive layer at least covering the die-cut edge region of the groove where the tab is located.

2. The solid-state battery cell according to claim 1, wherein, The conductive adhesive layer at least covers the die-cut edge area of ​​each groove in the electrode layer.

3. The solid-state battery cell according to claim 1, wherein, The conductive adhesive layer at least covers the cut edge region of the electrode layer.

4. The solid-state battery cell according to any one of claims 1 to 3, wherein, In the electrode layer including the conductive adhesive layer, the region between the electrode active material layer and the current collector layer includes a covered area provided with the conductive adhesive layer, and may or may not include a blank area where the conductive adhesive layer is not provided; the percentage of the area of ​​the covered area relative to the area of ​​the electrode active material layer is 64% to 100% when projected along the Z direction.

5. The solid-state battery cell according to any one of claims 1 to 3, wherein, In the electrode layer including the conductive adhesive layer, the projected area of ​​the conductive adhesive layer coincides with that of the electrode active material layer, measured along the Z direction.

6. The solid-state battery cell according to any one of claims 1 to 5, wherein, The conductive adhesive layer comprises an adhesive matrix and a conductive material.

7. The solid-state battery cell according to claim 6, wherein, The electrode layer including the conductive adhesive layer satisfies one or more of the following characteristics: The viscous matrix comprises a polyolefin resin; the polyolefin resin comprises one or more of the following polyolefin resins and polyolefin modified resins based on any of the following polyolefin resins: polyethylene, polypropylene, ethylene-vinyl acetate copolymer, styrene-butadiene copolymer, styrene-ethylene-butene-styrene block copolymer, styrene-isoprene-styrene block copolymer, and amorphous polyalphaolefin; the polyolefin modified resin is a copolymer of the polyolefin resin with maleic anhydride and petroleum resin; The conductive material includes carbon conductive materials, which include one or more of the following: superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, carbon nanofibers, and mesophase carbon microspheres. In the conductive adhesive layer, the mass ratio of the adhesive matrix to the conductive material is (0.6–1.5):1; The resistivity of the electrode layer including the conductive adhesive layer is 10 Ω·m to 1000 Ω·m, and the adhesion between the current collector layer and the electrode active material layer in the electrode layer is 1 N / m to 50 N / m.

8. The solid-state battery cell according to claim 7, wherein, The conductive adhesive layer satisfies one or more of the following characteristics: The viscous matrix includes a polyolefin modified resin, which is a copolymer of the polyolefin resin, maleic anhydride, and petroleum resin in a mass ratio of 30:(2-5):(8-12). The conductive material includes carbon conductive materials; The sum of the masses of the adhesive matrix and the conductive material accounts for 90% to 98% of the mass of the conductive adhesive layer. In the conductive adhesive layer, the mass ratio of the adhesive matrix to the conductive material is (0.8–1.4):1; The resistivity of the electrode layer including the conductive adhesive layer is 10 Ω·m to 200 Ω·m, and the adhesion between the current collector layer and the electrode active material layer in the electrode layer is 3 N / m to 20 N / m.

9. The solid-state battery cell according to any one of claims 6 to 8, wherein, The electrode active material layer includes a conductive agent; in the same electrode layer, taking one side of the current collector layer as a reference, the mass percentage of the conductive material in the conductive adhesive layer is higher than the mass percentage of the conductive agent in the electrode active material layer.

10. The solid-state battery cell according to any one of claims 1 to 9, wherein, In the corresponding electrode layer, the thickness of the conductive adhesive layer is 0.5 μm to 3 μm, taking into account one side of the current collector layer.

11. The solid-state battery cell according to claim 10, wherein, In the corresponding electrode layer, the thickness of the conductive adhesive layer is 0.5 μm to 1.5 μm, measured on one side of the current collector layer.

12. The solid-state battery cell according to any one of claims 1 to 11, wherein, The active region in the solid-state battery cell located at the height of the first composite groove and the second composite groove is denoted as the active extension region of the battery cell; The height of the electrode body at the active extension region of the battery cell is higher than the height of the electrode body at any composite groove.

13. The solid-state battery cell according to claim 12, wherein, The height of the solid-state battery cell in the Y direction is denoted as H0; the maximum height of the active extension region of the battery cell in the Y direction is denoted as H. Δ The utilization rate ψ of the active extension region of the cell in the Y direction Y =H Δ / H0×100%; Let W0 be the width of the solid-state battery cell in the X direction, and let W be the width of the active extension region of the battery cell in the X direction. Δ The utilization rate ψ of the active extension region of the cell in the X direction. X =W Δ / W0×100%; Let A0 be the projected area of ​​the solid-state battery cell along the Z direction, and let A be the projected area of ​​the active extension region of the battery cell along the Z direction. Δ The two-dimensional utilization rate ψ of the active extended region of the battery cell A =A Δ / A0×100%; The solid-state battery cell satisfies one or more of the following characteristics: H Δ ≥0.05mm; ψ Y ≥0.05%; IN Δ ≥50mm; ψ X ≥60%; ψ A ≥0.04%.

14. The solid-state battery cell according to claim 13, wherein, The solid-state battery cell satisfies one or more of the following characteristics: 0.05mm≤H Δ ≤1mm; 0.1%≤ψ Y ≤2%; 50mm≤W Δ ≤1000mm; 60%≤ψ X ≤95%; 0.04%≤ψ A ≤1.5%.

15. The solid-state battery cell according to any one of claims 1 to 13, wherein, The groove in the electrode layer where the tabs are provided is called the tab groove, and the extension height of any tab in the Y direction is greater than the height of the corresponding tab groove in the Y direction.

16. The solid-state battery cell according to any one of claims 1 to 15, wherein, At least a portion of the tabs have a bent section within the corresponding groove.

17. The solid-state battery cell according to any one of claims 1 to 16, wherein, The width of the positive electrode ear in the X direction is smaller than the width of the first composite groove in the X direction; the width of the negative electrode ear in the X direction is smaller than the width of the second composite groove in the X direction.

18. The solid-state battery cell according to claim 17, wherein, In the X direction, there is a gap between the positive electrode ear and the two side edges of the first composite groove, and there is a gap between the negative electrode ear and the two side edges of the second composite groove.

19. The solid-state battery cell according to any one of claims 1 to 18, wherein, The solid-state battery cell has a stacked structure.

20. The solid-state battery cell according to claim 19, wherein, The positive electrode portion includes a positive electrode body and a positive electrode tab connected to the positive electrode body. The positive electrode body includes at least one positive electrode layer, which includes a positive electrode current collector layer and a positive electrode active material layer located on at least one side of the positive electrode current collector layer. Each positive electrode layer has a groove corresponding to the first composite groove and the second composite groove, respectively. In the at least one positive electrode layer, the positive electrode current collector layer is connected to the bottom of at least one of the grooves with a positive electrode tab. The positive electrode layer also includes a positive electrode conductive adhesive layer located between the positive electrode current collector layer and the positive electrode active material layer. The positive electrode conductive adhesive layer at least covers the die-cut edge area of ​​the groove where the positive electrode tab is located. All the positive electrode tabs connected to the positive electrode body together constitute at least a part of the positive electrode tab portion. The negative electrode portion includes a negative electrode body and a negative electrode tab connected to the negative electrode body. The negative electrode body includes at least one negative electrode layer, which includes a negative electrode current collector layer and a negative electrode active material layer located on at least one side of the negative electrode current collector layer. Each negative electrode layer has a groove corresponding to the first composite groove and the second composite groove, respectively. In the at least one negative electrode layer, the negative electrode current collector layer is connected to the bottom of at least one of the grooves with a negative electrode tab. The negative electrode layer also includes a negative electrode conductive adhesive layer located between the negative electrode current collector layer and the negative electrode active material layer. The negative electrode conductive adhesive layer at least covers the die-cut edge area of ​​the groove where the negative electrode tab is located. All the negative electrode tabs connected to the negative electrode body together constitute at least a part of the negative electrode tab portion. The solid electrolyte section includes at least one solid electrolyte layer, and any adjacent positive electrode layer and negative electrode layer are isolated by the solid electrolyte layer; each solid electrolyte layer is provided with an empty groove corresponding to the first composite groove and the second composite groove respectively.

21. The solid-state battery cell according to claim 20, wherein, The positive electrode body has multiple positive electrode layers; the negative electrode body has the same number of negative electrode layers as the positive electrode body.

22. The solid-state battery cell according to claim 20 or 21, wherein, The positive electrode body has multiple positive electrode layers connected to the positive electrode tabs; the negative electrode body has multiple negative electrode layers connected to the negative electrode tabs.

23. A method for preparing a solid-state battery cell, comprising the following steps: Prepare a required number of positive electrode sheets, each positive electrode sheet comprising a positive current collector layer and a positive active material layer located on at least one side of the positive current collector layer; at at least one edge in the height direction of the positive electrode sheet, the positive electrode sheet is provided with a positive tab groove and a first empty groove; at least one of the positive electrode sheets further comprises a positive tab connected to the positive current collector layer and a conductive adhesive layer located between the positive current collector layer and the positive active material layer, the conductive adhesive layer being referred to as the positive conductive adhesive layer, the positive tab being connected to the bottom of the positive tab groove of the corresponding positive electrode sheet, the positive conductive adhesive layer at least covering the die-cut edge area of ​​the positive tab groove; Prepare a required number of negative electrode sheets, each negative electrode sheet comprising a negative electrode current collector layer and a negative electrode active material layer located on at least one side of the negative electrode current collector layer; at at least one edge in the height direction of the negative electrode sheet, the negative electrode sheet is provided with a negative electrode tab groove and a second empty groove; at least one of the negative electrode sheets further comprises a negative electrode tab connected to the negative electrode current collector layer and a conductive adhesive layer located between the negative electrode current collector layer and the negative electrode active material layer, the conductive adhesive layer being referred to as the negative electrode conductive adhesive layer, the negative electrode tab being connected to the bottom of the negative electrode tab groove of the corresponding negative electrode sheet, the negative electrode conductive adhesive layer at least covering the die-cut edge area of ​​the negative electrode tab groove; Prepare the specified number of solid electrolyte membranes, wherein the solid electrolyte membranes are provided with a fourth cavity and a third cavity; The positive electrode, the solid electrolyte membrane, and the negative electrode are stacked in the required quantities, with the positive and negative electrode separated by the solid electrolyte membrane. The outlines of the positive electrode tab groove, the fourth empty groove, and the second empty groove are aligned to form a first composite groove, and the outlines of the negative electrode tab groove, the third empty groove, and the first empty groove are aligned to form a second composite groove, thus obtaining a laminated component; wherein... Each positive electrode sheet constitutes a positive electrode portion, each negative electrode sheet constitutes a negative electrode portion, and each solid electrolyte membrane sheet constitutes a solid electrolyte portion; each positive electrode tab of the positive electrode portion constitutes a positive electrode tab soft segment, and at least a portion of the positive electrode tab soft segment is accommodated in the first composite groove; each negative electrode tab of the negative electrode portion constitutes a negative electrode tab soft segment, and at least a portion of the negative electrode tab soft segment is accommodated in the second composite groove; The laminated components are rolled to form the solid-state battery cell.

24. The method for preparing a solid-state battery cell according to claim 23, wherein, The positive electrode sheet, including the positive tab, is prepared by a method comprising the following steps: On the surface of the positive electrode current collector membrane, a positive electrode body region and a positive electrode inactive region adjacent to each other are identified by a first boundary line. The first boundary line extends along the width direction of the positive electrode current collector membrane in a concave shape, such that the positive electrode inactive region includes a positive electrode tab concave region and a first concave region concave towards the positive electrode body region, and the positive electrode tab concave region and the first concave region are separated by the positive electrode body region; wherein, the positive electrode tab concave region is matched with the position of the positive electrode tab groove, and the first concave region is matched with the position of the first empty groove; On at least one side surface of the positive electrode current collector film, the positive electrode conductive adhesive layer is applied to at least a portion of the positive electrode body region with the first dividing line as the coating boundary. On at least one side surface of the positive electrode current collector membrane to which the positive electrode conductive adhesive layer is attached, a positive electrode active pre-coating layer is applied so that the positive electrode active pre-coating layer covers the positive electrode body region, the positive electrode tab recess region and the first recess region. Remove the portion of the positive electrode active pre-coating that covers the concave area of ​​the positive electrode tab and the first concave area, exposing the corresponding positive electrode current collector film surface, to obtain a positive electrode die slice; wherein, the remaining portion of the positive electrode active pre-coating corresponds to the positive electrode active material layer, and the portion of the positive electrode current collector film covered by the positive electrode active material layer corresponds to the positive electrode current collector layer; The positive electrode sheet is die-cut according to the first dividing line to form the positive electrode plate; wherein, the die-cutting process of the positive electrode sheet according to the first dividing line includes: die-cutting out the corresponding contour of the positive active material layer except for the concave area of ​​the positive electrode tab, die-cutting out the contour of the two side edges of the positive electrode tab groove and the positive electrode tab connected to the positive current collector layer in the concave area of ​​the positive electrode tab, and die-cutting out the first empty groove in the first concave area according to the first dividing line.

25. The method for preparing a solid-state battery cell according to claim 24, wherein, The negative electrode sheet, including the negative electrode tab, is prepared by a method comprising the following steps: On the surface of the negative electrode current collector membrane, a negative electrode body region and a negative electrode inactive region adjacent to each other are identified by a second boundary line. The second boundary line extends along the width direction of the negative electrode current collector membrane in a concave shape, such that the negative electrode inactive region includes a negative electrode tab concave region and a second concave region concave towards the negative electrode body region, and the negative electrode tab concave region and the second concave region are separated by the negative electrode body region; wherein, the negative electrode tab concave region is matched with the negative electrode tab groove, and the second concave region is matched with the second empty groove. On at least one side surface of the negative electrode current collector film, the negative electrode conductive adhesive layer is applied to at least a portion of the negative electrode body region with the second dividing line as the coating boundary. On at least one side surface of the negative electrode current collector film to which the negative electrode conductive adhesive layer is attached, an additional negative electrode active pre-coating layer is applied so that the negative electrode active pre-coating layer covers the negative electrode body region, the negative electrode tab recess region, and the second recess region. Remove the portion of the negative electrode active pre-coating layer covering the negative electrode tab recess and the second recess, exposing the corresponding negative electrode current collector film surface to obtain a negative electrode die slice; wherein, the remaining portion of the negative electrode active pre-coating layer corresponds to the negative electrode active material layer, and the portion of the negative electrode current collector film covered by the negative electrode active material layer corresponds to the negative electrode current collector layer; The negative electrode sheet is die-cut according to the second dividing line to form the negative electrode sheet; wherein, the die-cutting process of the negative electrode sheet according to the second dividing line includes: die-cutting out the corresponding contour of the area of ​​the negative electrode active material layer other than the negative electrode tab concave area, die-cutting out the contour of the two side edges of the negative electrode tab groove and the negative electrode tab connected to the negative electrode current collector layer in the negative electrode tab concave area, and die-cutting out the second empty groove in the second concave area according to the second dividing line.

26. The method for preparing a solid-state battery cell according to claim 25, wherein it satisfies one or more of the following characteristics: During the preparation of the positive electrode sheet including the positive tab, the positive electrode conductive adhesive layer is coated on at least one side surface of the positive electrode current collector film, with the first dividing line as the coating boundary, over the entire area of ​​the positive electrode body region. In the process of preparing the negative electrode sheet including the negative electrode tab, the negative electrode conductive adhesive layer is coated on at least one side surface of the negative electrode current collector film, with the second dividing line as the coating boundary, over the entire area of ​​the negative electrode body region.

27. The method for preparing a solid-state battery cell according to claim 25 or 26, wherein it satisfies one or more of the following characteristics: In the positive electrode sheet including the positive tab, in the height direction of the positive electrode sheet, the extension height of the positive tab in the positive electrode sheet is greater than the height of the corresponding positive tab groove in the positive electrode sheet; In the negative electrode sheet including the negative electrode tab, in the height direction of the negative electrode sheet, the extension height of the negative electrode tab in the negative electrode sheet is greater than the height of the corresponding negative electrode tab groove in the negative electrode sheet.

28. The method for preparing a solid-state battery cell according to any one of claims 25 to 27, wherein it satisfies one or more of the following characteristics: In the prepared solid-state battery cell, at least a portion of the positive electrode tab has a bent section within the first composite groove; In the prepared solid-state battery cell, at least a portion of the negative electrode tab has a bent section within the second composite groove.

29. The method for preparing a solid-state battery cell according to any one of claims 25 to 28, wherein it satisfies one or more of the following characteristics: In the positive electrode sheet including the positive electrode tab, the width of the positive electrode tab is smaller than the width of the corresponding positive electrode tab groove in the width direction of the positive electrode sheet; In the negative electrode sheet including the negative electrode tab, the width of the negative electrode tab is smaller than the width of the corresponding negative electrode tab groove in the width direction of the negative electrode sheet.

30. The method for preparing a solid-state battery cell according to any one of claims 25 to 29, wherein it satisfies one or more of the following characteristics: In the positive electrode sheet including the positive electrode tab, there is a gap between the positive electrode tab and the two side edges of the positive electrode tab groove in the width direction of the positive electrode sheet; In the negative electrode sheet including the negative electrode tab, there is a gap between the negative electrode tab and the two side edges of the negative electrode tab groove in the width direction of the negative electrode sheet.

31. The method for preparing a solid-state battery cell according to any one of claims 23 to 29, wherein, The required number of positive electrode plates is multiple; the required number of negative electrode plates matches the required number of positive electrode plates.

32. The method for preparing a solid-state battery cell according to claim 31, wherein, The plurality of positive electrode plates include the positive electrode tabs; the plurality of negative electrode plates include the negative electrode tabs.

33. The method for preparing a solid-state battery cell according to claim 23, wherein, The solid-state battery cell prepared is the solid-state battery cell described in any one of claims 1 to 22.

34. A solid-state battery comprising at least one of the solid-state cells according to any one of claims 1 to 22 and solid-state cells prepared by the method of preparing solid-state cells according to any one of claims 23 to 32.

35. The solid-state battery according to claim 34, wherein, The solid-state battery is an all-solid-state battery.

36. An electrical device comprising at least one of the following: a solid-state battery cell according to any one of claims 1 to 22; a solid-state battery cell prepared by the method of preparing a solid-state battery cell according to any one of claims 23 to 32; and a solid-state battery according to claim 34 or 35.

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