Plates and batteries

Abstract

The present application provides an electrode plate and a battery, the electrode plate comprising a first current collector and a first functional layer provided on at least one surface of the first current collector, the first functional layer including active material particles, the first functional layer having a number of first regions and a number of second regions alternately distributed with respect to the first regions on the surface thereof, and an inorganic salt layer being present outside a portion of the active material particles within the first regions. The electrode plate and the battery provided by the present application are applied to improve initial charge / discharge efficiency and solve the problem of severe battery expansion.

Description

[Technical field]

[0001] This application relates to the field of lithium batteries, and in particular to plates and batteries. [Background technology]

[0002] Anode materials are attracting attention as an important factor in the development of lithium-ion batteries. There are two main types of anode materials for lithium-ion batteries: carbon materials and non-carbon materials.

[0003] At present, graphite, a carbon material, is mainly used as the negative electrode material for commercial lithium-ion batteries. It has been found that silicon is currently the negative electrode material with the highest theoretical lithium storage capacity, and its specific capacity is much higher than that of the traditional commercial graphite negative electrode material, which can greatly improve the energy density of lithium-ion batteries. However, during application, it has been found that the processed batteries have the disadvantage of low initial charge and discharge efficiency.

[0004] Therefore, in order to solve the problem of low initial charge / discharge efficiency of the battery, the electrode plate and the battery must be developed as soon as possible. Summary of the Invention [Problem to be solved by the invention]

[0005] The present application provides a plate and a battery for improving the first charge efficiency of the battery and solving the technical problem of severe battery expansion. [Means for solving the problem]

[0006] In order to achieve the above object, the present application provides an electrode plate including a first current collector and a first functional layer provided on at least one surface of the first current collector, the first functional layer including active material particles, the first functional layer having, on a surface thereof, several first regions and several second regions alternately distributed with respect to the first regions; In the first region, an inorganic salt layer is present outside some of the active material particles.

[0007] In the electrode plate provided by the present application, since there is an inorganic salt layer outside a part of the active material particles in the first region, the inorganic salt layer can be used to form protection in advance, thereby effectively improving the first charge efficiency and avoiding the expansion and rupture of silicon particles, and at the same time, mitigating the repeated expansion and rupture of silicon particles caused by lithium insertion during the silicon cycling process, contributing to reducing the expansion of silicon, thereby reducing the relative expansion of the battery, and achieving the effect of improving the expansion problem and cycle life of the battery.

[0008] In one possible embodiment, the porosity of the first region is less than the porosity of the second region.

[0009] In one possible embodiment, the porosity of the first region is between 21% and 29%; and / or The porosity of the second region is 30% to 34%.

[0010] In one possible embodiment, the inorganic salt layer comprises at least one of lithium fluoride or lithium carbonate, lithium silicate, and / or The weight percentage of the inorganic salt layer in the first region is greater than the weight percentage of the inorganic salt layer in the second region.

[0011] In one possible embodiment, the width of the first region is between 100 μm and 4 mm; and / or The width of the second region is 0 μm to 4 mm.

[0012] In one possible embodiment, within said first region, the ratio of the content of elemental oxygen to elemental silicon is greater than 4:1.

[0013] In one possible embodiment, within said first region, the ratio of the content of elemental fluorine to elemental phosphorus is greater than 7:1.

[0014] In one possible embodiment, in the second region, the ratio S1:S2 of the contents of silicon and oxygen elements satisfies 2:1≦S1:S2≦4:1.

[0015] In one possible embodiment, in the second region, the ratio S3:S4 of the content of fluorine element to the content of phosphorus element in the first functional layer satisfies 6:1≦S3:S4≦7:1.

[0016] In one possible embodiment, the active material particles comprise at least one of a silicon material and a silicon oxide material, and graphite, and the mass of the silicon material and / or the silicon oxide material accounts for 7% to 50% of the total mass of the active material particles; or the active material particles include a carbon material and graphite; or The active material particles contain at least one of a silicon material and a silicon oxide material, and a carbon material, and the mass of the silicon material and / or the silicon oxide material accounts for 7% to 50% of the total mass of the active material particles.

[0017] In one possible embodiment, the extension direction of the first region forms a first angle with the width direction of the first functional layer, the first angle being in the range of 0° to 45°, and / or a total area of ​​the first regions; and Multiple and / or the ratio of the total area of ​​the second region is 0.7:1 to 3:1; and / or With respect to the surface of the first current collector as a reference, the portion of the first region farthest from the first current collector is higher than the second region, and the difference in height between the portion of the first region farthest from the first current collector and the portion of the second region farthest from the first current collector is 0.1 μm to 8 μm.

[0018] In one possible embodiment, the electrode plate further comprises a first electrode tab and a first adhesive layer formed on a surface of the first functional layer, the first functional layer having a first groove, at least a portion of the first electrode tab being disposed in the first groove and covered by the first adhesive layer, and the first adhesive layer covering at least one of the first regions.

[0019] In one possible embodiment, the first groove has a first side, a second side, and a third side, and a direction from the first side to the second side is parallel to a length direction of the first functional layer; The portion of the first adhesive layer disposed on the surface of the first functional layer on the first side of the first groove covers 0 to 8 of the first regions, and / or The portion of the first adhesive layer disposed on the surface of the first functional layer on the second side of the first groove covers 0 to 8 of the first regions, and / or The portion of the first adhesive layer disposed on the surface of the first functional layer on the third side of the first groove covers 0 to 40 of the first regions, and / or a portion of the first adhesive layer disposed on the surface of the first functional layer on the first side of the first groove has a width of 1 mm to 5 mm in the longitudinal direction of the first functional layer; and / or The portion of the first adhesive layer disposed on the surface of the first functional layer on the second side of the first groove has a width of 1 mm to 5 mm in the longitudinal direction of the first functional layer.

[0020] The present application further provides a battery comprising a sealed case and a battery cell disposed inside the sealed case, the battery cell comprising a first plate and a second plate, the first plate being the plate described above, and the polarity of the second plate being opposite to the polarity of the first plate.

[0021] In one possible embodiment, a second adhesive layer is provided on one end of the second plate in the area covered by the first plate; The number of the first regions of the first plate corresponding to the second adhesive layer is 0 to 20; and / or The second electrode plate comprises a second current collector and a second functional layer provided on a surface of the second current collector, and at one end of the second electrode plate, there is a second blank foil area where the second functional layer is not provided, and the second adhesive layer covers at least a portion of the second blank foil area and extends from the second blank foil area to the surface of the second functional layer, and / or The second adhesive layer has a width of 3 mm to 5 mm in the longitudinal direction of the second electrode plate.

[0022] In one possible embodiment, the first functional layer is provided with a first groove, and a third adhesive layer is provided on the surface of the second plate at a position corresponding to the position of the first groove, and / or The second electrode plate comprises a second current collector and a second functional layer provided on a surface of the second current collector, the second functional layer is provided with a second groove and a fourth adhesive layer covering the second groove, and the second electrode plate is provided with a second electrode tab, at least a portion of the second electrode tab is disposed in the second groove and covered by the fourth adhesive layer.

[0023] In one possible embodiment, the first groove has a first side, a second side, and a third side, and a first projection of the third adhesive layer on the first plate covers at least one of the first regions, and the part of the first projection located on the first side of the first groove covers 0 to 8 of the first regions; and / or The portion of the first projection located on the second side of the first groove covers 0 to 8 of the first regions, and / or The portion of the first projection located on the third side of the first groove covers 0 to 40 of the first regions, and / or The second groove has a fourth side, a fifth side, and a sixth side, and the projection of the fourth adhesive layer on the first electrode plate covers at least one of the first regions, and the projection of the portion of the fourth adhesive layer disposed on the fourth side of the second groove on the first electrode plate covers 0 to 8 of the first regions; and / or The projection of the portion of the fourth adhesive layer disposed on the fifth side of the second groove on the first electrode plate covers 0 to 8 of the first regions, and / or The projection of the portion of the fourth adhesive layer disposed on the sixth side of the second groove onto the first electrode plate covers 0 to 40 of the first regions. Effect of the Invention

[0024] The electrode plate provided by the present application adopts a structure in which the second region and the first region are alternately distributed, and there is an inorganic salt layer outside the active material particles in the first region, which may be an inorganic salt layer pre-formed by inserting a lithium source into the active material particles in the first region, thereby preventing the silicon particles in the active material particles from expanding and bursting.

[0025] The electrode plate provided by the present application reduces the porosity by pre-inserting a lithium source, and at the same time, mitigates the repeated expansion and rupture of silicon particles caused by lithium insertion during the cycling process of silicon in the active material particles, contributing to reducing the expansion of silicon, thereby reducing the relative expansion of the battery, and achieving the effect of improving the expansion problem and cycle life of the battery.

[0026] In the plate and battery provided by the present application, a plurality of first regions are separated by second regions, i.e., two adjacent first regions are separated by a second region not supplemented with lithium, so that the entire surface of the first functional layer is not completely covered by the lithium supplemented region, and the second region allows the electrolyte to more easily infiltrate the plate and reduces the side reaction between metallic lithium and the electrolyte, thereby improving the utilization rate of lithium metal, optimizing the performance of the plate and the battery, improving the initial charge and discharge efficiency of the battery, and at the same time, improving the charging cycle performance of the battery, which is advantageous for extending the service life of the battery. In addition, by providing a first adhesive layer covering at least one first region on the surface of the first functional layer, it is possible to prevent the problem of lithium precipitation in the first region, and improve the performance of the plate and the battery, such as safety. [Brief description of the drawings]

[0027] In order to more clearly describe the embodiments of the present application or the solutions of the prior art, the following will briefly describe the drawings that need to be used in the description of the embodiments or the prior art. Of course, the drawings described below are some embodiments of the present application, and those skilled in the art can think of other drawings based on these drawings without creative efforts. [Figure 1] FIG. 2 is a structural schematic diagram of a plate provided by an embodiment of the present application. [Diagram 2] 2A-2C are SEM images taken from a first region and a second region of a plate provided according to an embodiment of the present application. [Diagram 3] FIG. 2 is a CP (Cross section Polisher) diagram of a second region of a plate provided by an embodiment of the present application. [Figure 4] FIG. 2 is a CP (Cross section Polisher) diagram of a first region of a plate provided by an embodiment of the present application. [Diagram 5] FIG. 2 is an X-ray energy spectrum sweep diagram of a plate provided by an embodiment of the present application. [Figure 6]FIG. 6 is an enlarged analysis of a portion of FIG. 5 of a plate provided according to an embodiment of the present application. [Figure 7] 1 is a high-resolution XPS (X-ray photoelectron spectroscopy) energy spectrum of local F1s of a plate provided by an embodiment of the present application. [Figure 8] 1 is a high-resolution XPS (X-ray photoelectron spectroscopy) energy spectrum of local Si2p of a plate provided by an embodiment of the present application. [Figure 9] FIG. 2 is a comparative capacity retention curve diagram of the cycle performance of a battery provided by an embodiment of the present application and a conventional battery. [Figure 10] FIG. 2 is a comparison diagram of expansion curves of cycle performance of a battery provided by an embodiment of the present application and a conventional battery. [Figure 11] FIG. 2 is a structural schematic diagram of a cross section perpendicular to the thickness direction of a negative electrode current collector of a first electrode plate provided according to an embodiment of the present application. [Figure 12] FIG. 2 is a structural schematic diagram of a cross section perpendicular to the thickness direction of a negative electrode current collector of a first electrode plate provided according to an embodiment of the present application. [Figure 13] FIG. 2 is a structural schematic diagram of a cross section perpendicular to the thickness direction of a negative electrode current collector of a second electrode plate provided according to an embodiment of the present application. [Figure 14] FIG. 2 is a surface view of a first electrode plate provided according to an embodiment of the present application measured by a 3D microscope. [Figure 15] FIG. 2 is a structural schematic diagram of the arrangement of lithium bands during the manufacturing process of the first electrode plate provided by an embodiment of the present application. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] In order to make the objectives, technical solutions and advantages of the present application clearer, the technical solutions are described below clearly and completely with reference to the drawings related to the present application, and it should be understood that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments thereof, and all other embodiments obtained by those skilled in the art without creative labor based on the embodiments in the present application all belong to the protection scope of the present application.

[0029] The initial charge / discharge efficiency affects the battery capacity, and refers to the ratio of the capacity discharged after the first full charge of a lithium-ion battery to the capacity after the first full charge. During the initial charge / discharge process, the negative electrode consumes some of the lithium ions from the positive electrode to form a solid electrolyte interface (SEI) film. Since the lithium ions consumed by the formed SEI film are irreversible, fewer lithium ions can ultimately return to the positive electrode, and the actual capacity of the battery is smaller than the theoretical capacity.

[0030] In addition, lithium ions are easily intercalated into the silicon material of the negative electrode, which causes the silicon particles to burst and expand, reducing the capacity and cycle life of the battery.

[0031] In view of the above background, the plate and battery provided by the present application have an inorganic salt layer, which can mitigate the re-expansion and explosion of silicon particles caused by lithium ions being inserted into the silicon particles during charging, suppress the volume expansion of the plate during charging, and improve the capacity and cycle life of the battery. The porosity of the first region is set to 21% to 29%, which can improve the expansion problem and cycle life of the battery.

[0032] The electrode plate and the battery provided by the present application will be described below with reference to the drawings.

[0033] As shown in FIG. 1, the present application provides an electrode plate having a first current collector 10 and a first functional layer 20 provided on at least one surface of the first current collector 10, and as shown in FIGS. 2 and 4, the first functional layer 20 includes active material particles, and the first functional layer 20 has, on its surface, several first regions 30 and several second regions 40 distributed alternately with respect to the first regions 30, and in the first regions 30, there is an inorganic salt layer 50 outside some of the active material particles.

[0034] In one possible embodiment, the active material particles include at least one of a silicon material and a silicon oxide material, and a carbon material, and a lithium material layer is provided on the surface of the first functional layer 20; The active material particles By reacting with the lithium material layer, a portion of the first functional layer 20 is formed as a first region 30, and an inorganic salt layer 50 is encapsulated around silicon particles in at least one of the silicon material, silicon oxide material, and carbon material within the first region 30.

[0035] The present application provides an electrode plate, in which a lithium material layer is provided on the surface of a first functional layer 20, and active material particles are reacted with the lithium material layer to form a part of the first functional layer 20 as a first region 30, and an inorganic salt layer 50 is present outside the part of the active material particles, and the inorganic salt layer 50 is wrapped around the silicon particles in at least one of the silicon material, the silicon oxide material, and the carbon material in the first region 30, and the lithium source of the lithium material layer is inserted around the silicon particles in at least one of the silicon material and the hard carbon material in the first region 30, thereby pre-forming the inorganic salt layer 50 to prevent the silicon particles from expanding and bursting, and at the same time, alleviating the repeated expansion and burst of the silicon particles caused by the insertion of lithium during the silicon cycle process, which contributes to reducing the expansion of silicon, thereby reducing the relative expansion of the battery, and achieving the effect of improving the expansion problem and cycle life of the battery.

[0036] The porosity of the first region 30 is smaller than that of the second region 40. The porosity of the first region 30 is 21% to 29%, and the porosity of the second region 40 is 30% to 34%. This is because in the first region 30, the pores 70 of the first functional layer 20 are filled with the inorganic salt layer 50, the porosity of the first region is 21% to 29%, and the inorganic salt layer 50 is formed in advance to reduce the porosity and alleviate the repeated expansion and rupture of silicon particles due to the insertion of lithium in the silicon cycle process, which contributes to reducing the expansion of silicon, thereby reducing the relative expansion of the battery.

[0037] In the first region 30, the lithium of the lithium material layer has an areal density of 0.09 mg / cm 2 ~0.5mg / cm 2 and the active material particles of the first functional layer 20 include at least one of a silicon material and a silicon oxide material, and graphite, where the mass of the silicon material and / or the silicon oxide material accounts for 7% to 50% of the mass of the active material particles, whereby the amount of lithium element is adapted to the amount of the silicon material and / or the silicon oxide material.

[0038] In one possible embodiment, the first functional layer 20 is an active material layer, the active material particles of the first functional layer 20 include hard carbon materials and graphite, and accordingly, in the first region 30, the lithium of the lithium material layer is arranged to have an areal density of 0.09 mg / cm, such that the amount of lithium element is adapted to the amount of silicon particles. 2 ~0.5mg / cm 2 We try to make it so.

[0039] In one possible embodiment, the active material particles include a carbon material and graphite, and the carbon material is a hard carbon.

[0040] In the first region 30, the lithium of the lithium material layer has an areal density of 0.09 mg / cm 2 ~0.5mg / cm 2and the active material particles of the first functional layer 20 include at least one of a silicon material and a silicon oxide material, and a carbon material, wherein the mass of the silicon material and / or the silicon oxide material accounts for 7% to 50% of the mass of the active material particles, and the carbon material may be hard carbon.

[0041] It is easy to understand that the porosity of the first region 30 refers to the percentage of the total volume of the pores 70 between the silicon material and the graphite and the total volume of the first region 30 in the natural state. The smaller the porosity, the smaller the space of the pores 70 between the silicon material and the graphite, which is unfavorable to the infiltration of the electrode plate, while the larger the porosity, the smaller the amount of lithium ions replenished, which is unfavorable to the improvement of the initial charge and discharge efficiency. The pores 70 of the first region 30 serve as a passage for infiltration during the process of the electrode plate deterioration, and the electrolyte can infiltrate the electrode plate through the pores 70 of the first region 30, effectively solving the problem that the electrode plate is difficult to infiltrate during the process of deterioration.

[0042] As shown in FIG. 4, the present application limits the amount of lithium ions replenished in the first region 30 within an appropriate range, thereby making the porosity of the first region 30 21% to 29%, thereby achieving the effect of improving the expansion problem and cycle life of the battery.

[0043] The lithium material layer may be a lithium band 80 and may appear as irregular stripes.

[0044] As shown in FIG. 1, the electrode plate provided by the present application is a negative electrode plate, and the first current collector 10 can be copper foil, titanium foil, nickel mesh, stainless steel foil, lithium copper alloy film, or carbon cloth.

[0045] A first functional layer 20 is provided on both sides of the first current collector 10 .

[0046] The material constituting the inorganic salt layer 50 is an inorganic salt, and the inorganic salt layer 50 is produced by inserting lithium ions of the first region 30 into silicon particles in the first functional layer 20. The mass percentage of the inorganic salt layer 50 in the first region 30 is greater than the mass percentage of the inorganic salt layer 50 in the second region 40.

[0047] The material constituting the inorganic salt layer 50 is LiF 、 Li2CO3 and The inorganic salt layer 50 includes at least one of Li4SiO4. The inorganic salt layer 50 is produced by a chemical reaction between the first functional layer 20 and lithium ions, and the chemical reaction is as follows: PF6 - +ne - + nLi + →LiF↓ + Li x PF y ↓ 2CO2+2e - +2Li + →Li2CO3↓+CO 4SiO2+12Li + →3Si+4Li2O+Li4SiO4

[0048] During processing of the electrode plate, the first functional layer 20 in the first region 30 is brought into contact with lithium ions in advance to cause a passivation reaction and form an SEI film. This prevents the electrode plate provided by the present application from re-absorbing lithium ions in the electrolyte when the battery processed in this manner is chemically formed, which is advantageous in that the lithium ions coming out of the second electrode plate are not consumed, thereby achieving the effect of improving the initial charge / discharge efficiency.

[0049] As shown in Figures 2 and 3, the first functional layer 20 further has second regions 40 alternately distributed with respect to the first regions 30. As shown in Figure 2, Figure 2 is a diagram obtained by photographing the first regions 30 and the second regions 40 using a scanning electron microscope (abbreviated as SEM) at a magnification of 50x-5.0kx, and the first regions 30 and the second regions 40 can be seen from Figure 2. The second regions 40 are for providing a region not having lithium element between adjacent first regions 30, and the second regions 40 are paths for infiltrating the electrode plate, contributing to improving the infiltration effect of the electrode plate.

[0050] Infiltration by the electrolyte generally relies on capillary action, and the present application provides a plate adopting a structure in which the second region 40 and the first region 30 are alternately distributed, so that the electrolyte can infiltrate through the second region 40 to infiltrate the plate, which reduces the hindrance to infiltration of the plate and is favorable for uniform infiltration of the plate, thereby improving the infiltration effect of the battery and improving the cycle life of the battery.

[0051] The porosity of the second region 40 is 30% to 34%, while the porosity of the inorganic salt layer 50 in the first region 30 is 21% to 29%. By pre-inserting the lithium material layer, the porosity of the first region 30 is reduced, which alleviates the repeated expansion and rupture of silicon particles caused by the insertion of lithium during the silicon cycle process, contributing to reducing the expansion of silicon, and thereby reducing the relative expansion of the battery.

[0052] The lithium material layer may be an ultra-thin metallic lithium band manufactured using asynchronous rolling technology, and on the surface of the ultra-thin metallic lithium band, a region corresponding to a first region 30 containing lithium element and a region corresponding to a second region 40 not containing lithium element are formed, and the lithium ions of the metallic lithium band are transferred to the first region 30, thereby forming the first region 30 and the second region 40 on the surface of the first functional layer 20.

[0053] As shown in FIG. 2, in order to meet the requirements of areal density of lithium replenishment and infiltration uniformity, the width of the first region 30 is 100 μm to 4 mm, i.e., the distance between two adjacent second regions 40 is 100 μm to 4 mm.

[0054] In one possible embodiment, the width of the first region 30 may be 100 μm, 1 mm, 2 mm, 3 mm, or 4 mm. In order to meet the requirements of areal density of lithium replenishment and infiltration uniformity, the width of the second region 40 is 0 μm to 4 mm, i.e., the distance between two adjacent first regions 30 is 0 μm to 4 mm.

[0055] The present application provides a plate in which the second regions 40 and the first regions 30 are alternately distributed and the width between the second regions 40 and the first regions 30 is limited, thereby meeting the requirements of areal density of lithium replenishment and improving the uniformity of electrolyte infiltration into the plate.

[0056] In one possible embodiment, the width of the second region 40 may be 10 μm, 1 mm, 2 mm, 3 mm, or 4 mm. When the lithium ions are partially intercalated into the silicon particles of the first region 30, the lithium ions transition to the non-intercalated region due to the solid phase concentration difference, thereby forming a transition region 60 between the first region 30 and the second region 40, so that the lithium ions inside the first region 30 are uniformly distributed, the effect of a consistent lithium intercalation state is achieved, the problems of lithium precipitation and purplish spots caused by the local higher lithium ions are avoided, and the overall uniformity of lithium intercalation is improved.

[0057] In the first region 30, the ratio of the content of elemental oxygen to elemental silicon is greater than 4:1.

[0058] In one possible embodiment, the ratio of the oxygen element content to the silicon element content in the first region 30 may be 4:1, 5:1, 6:1, or 7:1.

[0059] It can be easily understood that in the first region 30, when the content ratio of oxygen element to silicon element is greater than 4:1, lithium silicate is easily produced, lithium ions are consumed, and the expansion rate of the battery during cycling is reduced; in the first region 30, when the content ratio of oxygen element to silicon element is less than 4:1, the oxygen element is too much, which indicates that it will chemically react with the supplemented lithium ions, lithium oxide or lithium carbonate will be produced, and the utilization rate of lithium ions will be reduced.

[0060] The first functional layer 20 further contains elemental fluorine and elemental phosphorus, and the ratio of the content of elemental fluorine and elemental phosphorus in the first region 30 is greater than 7:1. In this way, during the initial charge and discharge of the battery, the lithium ions in the first region 30 react with the electrolyte to form a denser passivation layer, which becomes an SEI film, and the passivation layer becomes an excellent conductor of lithium ions, so that the lithium ions are transmitted in the passivation layer, and the lithium ions penetrate the graphite surface of the first functional layer 20 to promote the release of lithium, which contributes to improving the cycle performance of the battery and improving the service life of the battery.

[0061] Considering that the electrolyte is lithium hexafluorophosphate and the content ratio of elemental fluorine to elemental phosphorus in the first region 30 is greater than 7:1, the excess elemental fluorine will chemically react with lithium ions to produce lithium fluoride, i.e., a passivation layer. During the formation of the SEI film, the lithium ions will be partially consumed, which will increase the irreversible capacity during the initial charge / discharge and reduce the charge / discharge efficiency.

[0062] In the second region 40, the ratio S1:S2 of the content of oxygen element to the content of silicon element satisfies 2:1≦S1:S2≦4:1.

[0063] In the second region 40, the ratio S3:S4 of the content of elemental fluorine and elemental phosphorus in the first functional layer 20 satisfies 6:1≦S3:S4≦7:1.

[0064] Example 1

[0065] In this embodiment, the active material particles of the first functional layer 20 include graphite and silicon oxide material, and the mass of the silicon oxide material accounts for 7% of the total mass of the graphite and the silicon oxide material. Accordingly, in the first region 30, the lithium areal density of the lithium material layer is 0.12 mg / cm 2 The porosity of the first region 30 is 29% In the first region 30, the ratio of the content of oxygen element to the content of silicon element is 5:1, and in the second region 40, Oxygen and Silicon The ratio of the contents S1:S2 is 4 : 1 It may be so arranged.

[0066] Example 2

[0067] In this embodiment, the active material particles of the first functional layer 20 include graphite and silicon particles, and the mass of the silicon particles accounts for 20% of the total mass of the graphite and silicon particles. Accordingly, in the first region 30, the lithium areal density of the lithium material layer is 0.22. mg / cm 2 The porosity of the first region 30 is 27% In the first region 30, the ratio of the content of oxygen element to the content of silicon element is 6:1, and in the second region 40, Oxygen and Silicon The ratio of the contents S1:S2 is 4 : 1 It may be so arranged.

[0068] Example 3

[0069] In this embodiment, the active material particles of the first functional layer 20 include graphite and silicon oxide material, and the mass of the silicon oxide material accounts for 30% of the total mass of the graphite and the silicon oxide material. Accordingly, in the first region 30, the lithium areal density of the lithium material layer is 0.32. mg / cm 2 The porosity of the first region 30 is 25% In the first region 30, the ratio of the content of oxygen element to the content of silicon element is 6.5:1, and in the second region 40, Oxygen and Silicon The ratio of the contents S1:S2 is 4 :1 It may be so arranged.

[0070] Example 4

[0071] In this embodiment, the active material particles of the first functional layer 20 include graphite and silicon oxide material, and the mass of the silicon oxide material accounts for 40% of the total mass of the graphite and the silicon oxide material. Accordingly, in the first region 30, the lithium areal density of the lithium material layer is 0.42 mg / cm 2 The porosity of the first region 30 is 23% In the first region 30, the ratio of the content of oxygen element to the content of silicon element is 7:1, and in the second region 40, Oxygen and Silicon The ratio of the contents S1:S2 is 4 : 1 It may be so arranged.

[0072] Example 5

[0073] In this embodiment, the active material particles of the first functional layer 20 include graphite and silicon oxide material, and the mass of the silicon oxide material accounts for 50% of the total mass of the graphite and the silicon oxide material. Accordingly, in the first region 30, the lithium areal density of the lithium material layer is 0.5. mg / cm 2 The porosity of the first region 30 is 21% In the first region 30, the ratio of the content of oxygen element to the content of silicon element is 7.5:1, and in the second region 40, Oxygen and Silicon The ratio of the contents S1:S2 is 4 : 1 It may be so arranged.

[0074] In the above Examples 1 to 5, the active material particles of the first functional layer 20 include at least one of a silicon material and a silicon oxide material, and graphite, the proportion of the silicon material being 7% to 50% of the total mass of the active material particles, and the graphite may be artificial graphite or natural graphite. Accordingly, in the first region 30, the surface density of lithium in the lithium material layer is 0.09 mg / cm 2 ~0.5mg / cm 2This allows the amount of lithium element to be adapted to the amount of silicon particles, and if the amount of lithium element is too large, lithium ions will react with the electrolyte and precipitate, reducing the utilization rate of lithium ions, but if the amount of lithium element is too small, the effect of lithium supplementation cannot be fully exerted, and the initial charge / discharge efficiency will not be significantly improved.

[0075] Example 6

[0076] In this embodiment, the active material particles of the first functional layer 20 include hard carbon and silicon oxide material, and the mass of the silicon oxide material accounts for 7% of the total mass of the hard carbon and silicon oxide material. Accordingly, in the first region 30, the lithium areal density of the lithium material layer is 0.18. mg / cm 2 The porosity of the first region 30 is 28%, the ratio of the content of oxygen element to the content of silicon element in the first region 30 is 6:1, and in the second region 40, Oxygen and Silicon The ratio of the contents S1:S2 may be 4:1.

[0077] Example 7

[0078] In this embodiment, the active material particles of the first functional layer 20 include hard carbon and silicon oxide material, and the mass of the silicon oxide material accounts for 30% of the total mass of the hard carbon and silicon oxide material. Accordingly, in the first region 30, the lithium areal density of the lithium material layer is 0.28. mg / cm 2 The porosity of the first region 30 is 26%, the ratio of the oxygen element content to the silicon element content in the first region 30 is 7:1, and in the second region 40, Oxygen and Silicon The ratio of the contents S1:S2 is 4 : 1 It may be so arranged.

[0079] Example 8

[0080] In this embodiment, the active material particles of the first functional layer 20 include hard carbon and silicon oxide material, and the mass of the silicon oxide material accounts for 50% of the total mass of the hard carbon and silicon oxide material. Accordingly, in the first region 30, the lithium areal density of the lithium material layer is 0.34. mg / cm 2 The porosity of the first region 30 is 24%, the ratio of the oxygen element content to the silicon element content in the first region 30 is 8:1, and in the second region 40, Oxygen and Silicon The ratio of the contents S1:S2 is 4 : 1 It may be so arranged.

[0081] In the above Examples 6 to 8, the active material particles of the first functional layer 20 include hard carbon and silicon oxide material, and the mass of the silicon oxide material accounts for 7% to 50% of the total mass of the hard carbon and the silicon oxide material. Accordingly, in the first region 30, the lithium surface density of the lithium material layer is 0.09 mg / cm 2 ~0.5mg / cm 2 This allows the amount of lithium element to be adapted to the amount of silicon oxide material, and prevents the lithium element from reacting with the electrolyte and being precipitated, which reduces the utilization rate of lithium ions, due to the excess amount of lithium element, and at the same time, prevents the amount of lithium element from being too small, which prevents the effect of lithium supplementation from being fully exerted, and thus prevents the initial charge / discharge efficiency from being significantly improved.

[0082] Here, the electrode plate provided by Example 1 of the present application was prepared, and Al and Kα were used as excitation sources (1486.6 eV) for the first region 30 and the second region 40, respectively, to perform and detect F1s and Si2p.

[0083] 7 and 8, the content of the inorganic salt layer 50 in the first region 30 is greater than that in the second region 40. In FIG. 7, the ordinate indicates peak intensity, and the abscissa indicates binding energy, with the higher peak value indicating a higher content of the measured element. As is clear from FIG. 7, the characteristic peak in the binding energy region of 680-690 eV corresponds to F1s, and the peak intensity of the first region 30 is greater than that of the second region 40, indicating that the LiF content of the first region 30 is higher than that of the second region 40.

[0084] In FIG. 8, the ordinate indicates the peak intensity, and the abscissa indicates the binding energy. The higher the peak value, the higher the content of the element being measured. As can be seen from FIG. 8, the characteristic peak in the binding energy range of 100-105 eV corresponds to Si2p, and the peak intensity of the first region 30 is greater than that of the second region 40. This is because the Li x SiO y The content of Li in the second region 40 x SiO y This indicates that the content is higher than the content, so x=4 and y=4.

[0085] During processing, the first functional layer 20 is applied to the surface of the first current collector 10, and then it is dried in a dry environment at a temperature of 90°C for 24 hours to control the moisture content to 300 ppm or less to obtain a semi-finished electrode plate. Then, an ultra-thin metallic lithium band is manufactured using asynchronous rolling technology, and laminated with the semi-finished electrode plate to manufacture an electrode plate.

[0086] The present application further provides a battery comprising a sealed case and a battery cell disposed inside the sealed case, the battery cell comprising a first plate and a second plate, the first plate being the above-mentioned plate.

[0087] In one possible embodiment, the first plate uses the above plate as a negative plate and the second plate is a positive plate.

[0088] During processing, the first electrode plate, the second electrode plate, and a separator were stacked in that order, and the separator was placed between the first electrode plate and the second electrode plate, with the separator serving to separate the first electrode plate and the second electrode plate. The battery was then wound up to obtain a battery cell, which was then placed in a sealed case. An electrolyte was poured into the sealed case, vacuum sealed, left to stand, and formed. The battery was then charged to a 4% state of charge (abbreviated as SOC) at a constant current of 0.1C, and further charged to 10% SOC at a constant current of 0.2C. After going through processes such as shaping and capacity testing, a soft-pack lithium-ion battery was obtained.

[0089] In one possible embodiment, the sealed case may be an aluminum plastic film and the electrolyte may be lithium hexafluorophosphate.

[0090] In one possible embodiment, the first region 30 is a lithium-replenished region and the second region 40 is a non-lithium-replenished region, and 3D microscopy reveals that the first region 30 is bright and the second region 40 is dark (as shown in FIG. 14).

[0091] In one possible embodiment, lithium replenishment can be performed according to the following process: As shown in Fig. 15, a plurality of lithium bands 80 are arranged at intervals on the surface of the first functional layer 20 such that gaps C that expose the surface of the first functional layer 20 exist between the plurality of lithium bands 80, and when a reaction such as chemical conversion occurs in the battery manufacturing process, the region where the lithium bands 80 are provided is formed as a lithium replenished region, i.e., the first region 30, and the gaps C existing between the plurality of lithium bands 80 are formed as a region where lithium replenishment is not performed, i.e., the second region 40, and as shown in Fig. 14, the first region 30 is in a discontinuous state, which is favorable for the infiltration of the plate by the electrolyte through the second region 40, thereby improving the utilization rate of the lithium bands and optimizing the performance of the plate and the battery.

[0092] During lithium replenishment, the precursor of the electrode plate on which the first functional layer 20 is formed is dried for about 24 hours in a dry environment at about 90°C to control the moisture content to 300 ppm or less, and then a lithium band 80 is placed on the surface of the dried electrode plate, and the lithium band 80 is laminated with the first functional layer 20 by a process such as lamination, and lithium replenishment is performed.

[0093] The above-mentioned electrode plate can be obtained by a coating method, and its manufacturing process generally includes steps such as raw material blending (preparation of slurry), coating (applying the slurry to the surface of the current collector base material to form the first functional layer 20), roller pressing, slitting (performing slitting according to parameters such as the predetermined size and shape of the electrode plate), drying, etc., followed by subsequent processes such as lithium replenishment.

[0094] In one possible embodiment, the lithium band 80 used may include a strip-shaped lithium band whose length is smaller than the width of the first functional layer 20 (the distribution manner of the strip-shaped lithium band is shown in FIG. 15, and the surface state of the electrode plate formed thereby is shown in FIG. 14), and a plurality of strip-shaped lithium bands may be sequentially arranged in a row along the width direction (direction indicated by arrow B) of the first functional layer 20, and another row may be formed along the length direction (direction indicated by arrow A) of the first functional layer 20 according to the process, and the length of each row may be adjusted. can be smaller or equal to the width of the electrode plate (the length of the row of first regions 30 formed thereby is smaller or equal to the width of the electrode plate), but is not limited to this, and a plurality of rectangular lithium bands may be irregularly arranged on the surface of the first functional layer 20, or long lithium bands having a length approximately the same as the width of the first functional layer 20 may be arranged at intervals on the surface of the first functional layer 20 (for example, a gap is provided between any two adjacent long lithium bands, and the gap is formed as the second region 40 by chemical conversion).

[0095] In one possible embodiment, the amount of the lithium band 80 used is such that the ratio of the total mass of the lithium band 80 provided on the surface of the first functional layer 20 to the area of ​​the surface of the first functional layer 20 (the surface facing away from the first current collector 10) is 0.09 to 0.5 mg:1 m 2 The condition may be satisfied.

[0096] In one possible embodiment, the lithium band 80 may be 1.9 μm-9 μm thick. Because the theoretical specific capacity of pure metallic lithium is very high, if lithium replenishment is performed on the entire surface of the electrode plate, the thickness of the metallic lithium is usually about 1 μm, which is extremely difficult to manufacture and has poor consistency. In contrast, in the present application, lithium replenishment is performed using an ultra-thin metallic lithium band that does not cover the entire surface of the electrode plate, and the ultra-thin metallic lithium band is in a discontinuous coating state such as striped / wavy on the surface of its first functional layer 20, so that lithium replenishment can be effectively performed and the utilization rate of lithium metal can be improved. In addition, it has the advantages of being easy to manufacture and having good consistency.

[0097] In one possible embodiment, lithium replenishment is typically performed by pressing a lithium ingot to a micrometer-level thickness and then placing the resulting micrometer-level lithium band on the surface of the first functional layer 20. For example, in some embodiments, Thickness A lithium ingot of 200 μm to 2 mm is pressed into a lithium band 80 of 1.9 μm to 9 μm in thickness, and then placed on the surface of the first functional layer 20 to perform lithium replenishment.

[0098] In one possible embodiment, the inorganic salt layer may be an inorganic salt layer formed by intercalating the active material particles in the first region 30 with a lithium source for lithium replenishment, i.e., the material constituting the inorganic salt layer is an inorganic salt, and the inorganic salt layer is produced by intercalating the lithium element replenished in the first region 30 into the active material particles in the first region 30, and the inorganic salt layer includes, for example, at least one of lithium fluoride, lithium carbonate, lithium silicate, etc.

[0099] In one possible embodiment, the first regions 30 and the second regions 40 are arranged / distributed alternately, i.e., a plurality of first regions 30 and a plurality of second regions 40 are distributed on the surface of the first functional layer 20, and the surface of the first functional layer 20 is separated by a plurality of second regions 40 to form a plurality of first regions 30.

[0100] The multiple first regions 30 are distributed along the length direction of the first functional layer 20 / electrode plate (the direction indicated by arrow A), i.e., the multiple first regions 30 and the multiple second regions 40 may be distributed in an alternating sequence along the length direction of the first functional layer 20 / electrode plate.

[0101] In one possible embodiment, as shown in Figures 11, 12, and 14, the first region 30 may form a first angle in the extension / length direction with the width direction of the first functional layer 20, and the first angle may be 0° to 60°, and in one possible embodiment, the first angle may be 0° to 45°, such as 0° (i.e., the length direction of the first region 30 is parallel to the width direction of the first functional layer 20), 10°, 20°, 30°, 40°, or 45°, thus contributing to the lithium replenishment and electrolyte infiltration effects of the plate, while at the same time contributing to the manufacture and performance of the battery without affecting the winding of the plate along its length.

[0102] The extension directions of the multiple first regions 30 may be the same or different, i.e., the first angle formed between the extension direction of the first regions 30 and the width direction of the first functional layer 20 may be the same or different.

[0103] In addition, in the width direction of the first functional layer 20 / electrode plate, the distance between the first region 30 closest to the outer edge / periphery of the first functional layer 20 and the outer edge of the first functional layer 20 is defined as A, and A may be 0-2 mm, for example, 0 mm (i.e., the height of the first region 30 and the outer edge of the first functional layer 20 are the same), 0.5 mm, 1 mm, 1.5 mm, 2 mm, etc., and the ratio of A to the width of the first functional layer 20 may be 0-0.03, for example 0, 0.01, 0.02, 0.03, etc.

[0104] In one possible embodiment, at least one first region 30 forms a row in the width direction of the first functional layer 20, and the row may be continuous, i.e., the row is formed by a single first region 30 (not interrupted by a second region 40 in the middle), or the row may be discontinuous, i.e., the row is formed by multiple first regions 30 arranged sequentially along the width direction of the first functional layer 20, with a second region 40 present between two adjacent first regions 30 and interrupted by the second region 40.

[0105] Furthermore, the first region 30 extends along the width direction of the first functional layer 20, and in the width direction of the first functional layer 20, the first region 30 can have a generally straight structure or a folded / curved structure, etc.

[0106] Furthermore, in the length direction of the first functional layer 20 / electrode plate, the distance between the first region 30 closest to the outer edge of the first functional layer 20 and the outer edge of the first functional layer 20 (i.e., the distance between the second region 30 closest to the outer edge of the first functional layer 20 and the outer edge of the first functional layer 20) 40The width in the length direction of the first functional layer 20 (which is the width) may be 0 - 4 mm, for example, it may also be 100 μm to 4 mm.

[0107] In one possible embodiment, the first functional layer 20 has a first end and a second end facing each other. The direction from the first end to the second end is parallel to the length direction of the first functional layer 20. The distance w1 between the first region 30 closest to the first end and the edge of the first end of the first functional layer 20 (the edge of the first functional layer 20) is 100 μm to 4 mm, for example, 100 μm, 300 μm, 500 μm, 700 μm, 1 mm, 2 mm, 3 mm, 4 mm, etc. That is, in the length direction of the first functional layer 20, the width of the second region 40 existing between the first region 30 closest to the first end and the edge of the first end is w1. The distance w2 between the first region 30 closest to the second end (the edge of the first functional layer 20) and the edge of the second end of the first functional layer 20 is 0 μm to 4 mm, for example, 0 μm , 100 μm, 300 μm, 500 μm, 700 μm, 1 mm, 2 mm, 3 mm, 4 mm, etc.

[0108] When w2 = 0, there is no second region between the first region 30 closest to the second end of the first functional layer 20 and the edge of the second end of the first functional layer 20 (that is, the width w2 of the second region 40 between the first region 30 closest to the second end and the edge of the second end is 0). However, when w2 is not 0 (that is, 0 < w2 ≤ 4 mm), in the length direction of the first functional layer 20, there is a second region 40 with a width of w2 between the first region 30 closest to the second end of the first functional layer 20 and the edge of the second end.

[0109] In one possible embodiment, w1 and w2 may be the same or different.

[0110] In order to further achieve both improved lithium replenishment effect and improved electrolyte permeability, in some preferred embodiments, the ratio of the total area of ​​the multiple first regions 30 (i.e., the sum of the areas of the multiple first regions 30) to the total area of ​​the multiple second regions 40 (i.e., the sum of the areas of the multiple second regions 40) is 0.7:1 to 3:1, for example 0.7:1, 1:1, 1.5:1, 2:1, 2.5:1, or 3:1.

[0111] To measure the ratio of the total area of ​​the plurality of first regions 30 to the total area of ​​the plurality of second regions 40, a microscope can be used to capture the contours of the first regions 30 and the second regions 40.

[0112] Generally, the first region 30 and the second region 40 are defined such that, with respect to the surface of the first current collector 10, the first region 30 is higher than the second region 40, i.e., in the thickness direction of the first functional layer 20, the distance a between the part of the first region 30 farthest from the first current collector 10 and the first current collector 10 is greater than the distance b (a>b) between the part of the second region 40 farthest from the first current collector 10 and the first current collector 10.

[0113] In some embodiments, the difference in height between the portion of the first region 30 farthest from the first current collector 10 and the portion of the second region 40 farthest from the first current collector 10 is 0.1 μm to 8 μm (i.e., ab=0.1-8 μm), such as 0.1 μm, 0.5 μm, 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, or 8 μm.

[0114] In one possible embodiment, the means for measuring the height difference between the first region 30 and the second region 40 can include, but are not limited to, (1) sputtering the lithium-replenished plate using an ion milling (CP) machine to obtain a cross section and photographing it using a scanning electron microscope (SEM) to magnify and photograph it to the required magnification to obtain the height difference, and (2) photographing it using a 3D microscope to magnify and photograph it to the required magnification and measure the height difference using a profilometer.

[0115] In some embodiments, the first functional layer 20 is provided with a first groove 21 covered by a first adhesive layer 81. Here, the first groove 21 may function as an electrode tab groove for arranging an electrode tab, and in some embodiments, the plate further includes a first electrode tab 91 and a first adhesive layer 81 formed on the surface of the first functional layer 20, and at least a portion of the first electrode tab 91 is arranged in the first groove 21 and covered by the first adhesive layer 81 (i.e., the portion of the first electrode tab 91 arranged in the first groove 21 is covered by the first adhesive layer 81), thus protecting the electrode tab area and improving the safety of the plate and the battery, for example, to avoid the problem that lithium in the lithium supplement area around the first electrode tab moves to the positive electrode tab area during charging and discharging (corresponding to the position of the electrode tab groove where the positive electrode tab is arranged), and the lithium in the negative electrode tab area caused thereby is precipitated.

[0116] In one possible embodiment, the first adhesive layer 81 is arranged on a portion of the area of ​​the surface of the first functional layer 20, i.e. does not completely cover the first functional layer 20. The first adhesive layer 81 covers at least one first area 30.

[0117] In one possible embodiment, at least a portion of the bottom surface of the first groove 21 becomes the surface of the first current collector 10, i.e., a portion of the bottom surface of the first groove 21 is exposed to the first current collector 10, and the first electrode tab 91 may be connected to the first current collector 10 exposed at the bottom surface of the first groove 21, specifically, may be welded onto the first current collector 10 exposed at the bottom surface of the first groove 21.

[0118] Here, the plate may be of electrode tab center position (CPT) construction, i.e., the electrode tab may be located at the center of the plate rather than at the end.

[0119] In one possible embodiment, at least both sides of the first groove 21 are the first functional layer 20. In some embodiments, on a plane perpendicular to the thickness direction of the first current collector 10, the first groove 21 has one side flush with one long side of the first current collector 10 and the remaining side surrounded by the first functional layer 20, i.e., the first groove 21 has an opening facing one long side of the first current collector 10, and when the first electrode tab 91 is disposed, one end of the first electrode tab 91 can extend from the outer edge of the first current collector 10 through the opening, specifically, the first electrode tab 91 extends from the outer edge of the first current collector 10 through the opening along its length, and the portion of the first electrode tab 91 disposed in the first groove 21 (i.e., the portion not extending from the outer edge of the first current collector 10) may be covered by the first adhesive layer 81 (as shown in FIG. 12 ).

[0120] Here, the length direction of the first electrode tab 91 is parallel to the length direction of the first region 30 / second region 40 (i.e., the first tab 91 coincides with the extending direction of the first region 30 / second region 40).

[0121] As shown in Figure 11, the projection of the first groove 21 on the first current collector 10 is a rectangle, one of whose short sides is in the same plane as one of the long sides of the first current collector 10, and the remaining three sides are surrounded by the first functional layer 20.

[0122] In one possible embodiment, the first groove 21 has opposing first and second sides and opposing third and fourth sides, the third / fourth side being disposed between the first and second sides (the third / fourth side being connected to the first and second sides), and the direction from the first side to the second side being parallel to the direction from the first region to the second region.

[0123] 11 and 12, the first side is the left side, the second side is the right side, the third side is the bottom side, and the fourth side is the top side, and the left, right, and bottom sides of the first groove 21 are surrounded by the first functional layer 20, and the first functional layer 20 is not disposed on the top side (i.e., the top side of the first groove 21 is flush with the edge of the first functional layer 20). The direction from the first side to the second side is parallel to the length direction of the first functional layer 20, and the direction from the third side to the fourth side is parallel to the width direction of the first functional layer 20.

[0124] The first adhesive layer 81 extends to the surface of the first functional layer 20 around the first groove 21, and the portion of the first adhesive layer 81 arranged on the surface of the first functional layer 20 on the first side of the first groove 21 covers a1 first regions 30, where a1 is 0 to 8, for example 0, 1, 2, 3, 4, 5, 6, 7, 8, etc., i.e. the number of first regions arranged on the first side of the first groove 21 and in contact with the first adhesive layer 81 is a1, i.e. the surface of the first functional layer 20 includes a third region 85 arranged on the first side of the first groove 21 and covered by the first adhesive layer 81, and the number of first regions 30 extending into the third region 85 is a1.

[0125] For example, a1=1 as shown in FIG.

[0126] Furthermore, the portion of the first adhesive layer 81 arranged on the surface of the first functional layer 20 on the second side of the first groove 21 covers a2 first regions 30, where a2 is 0 to 8, i.e., the number of first regions 30 arranged on the second side of the first groove 21 and in contact with the first adhesive layer 81 is a2, i.e., the surface of the first functional layer 20 includes a fourth region 86 arranged on the second side of the first groove 21 and covered by the first adhesive layer 81, and the number of first regions 30 extending into the fourth region 86 is a2.

[0127] Illustratively, a2=1 is set as shown in FIG.

[0128] Furthermore, the portion of the first adhesive layer 81 arranged on the surface of the first functional layer 20 on the third side of the first groove 21 contacts a3 first regions 30, where a3 is 0 to 40, for example 0, 2, 5, 8, 10, 12, 15, 18, 20, 22, 25, 28, 30, 32, 35, 38, 40, etc., i.e., the number of first regions 30 arranged on the third side of the first groove 21 and in contact with the first adhesive layer 81 is a3, i.e., the surface of the first functional layer 20 includes a fifth region 87 arranged on the third side of the first groove 21 and covered by the first adhesive layer 81, and the number of first regions 30 extending into the fifth region 87 is a3.

[0129] As shown in FIGS. 11 and 12, a3 is also the total number of first regions 30 in contact with the first adhesive layer 81.

[0130] In one possible embodiment, all of the first regions 30 (a1) that extend into the third region 85 extend into the fifth region 87, all of the first regions 30 (a2) that extend into the fourth region 86 extend into the fifth region 87, and the number of first regions 30 that extend into the fifth region 87 and connect to the first groove 21 is a4, where a3 = a1 + a2 + a4.

[0131] For example, as shown in FIG. 11, a3=4, where a1=1, a2=1, and a4=2.

[0132] In one possible embodiment, the width w31 in the longitudinal direction of the first functional layer 20 (which is also the width in the longitudinal direction of the first functional layer 20 of the third region 85) of the portion of the first adhesive layer 81 arranged on the surface of the first functional layer 20 on the first side of the first groove 21 is 1 mm to 5 mm, for example 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, etc.

[0133] Furthermore, the width w32 in the longitudinal direction of the first functional layer 20 (which is also the width in the longitudinal direction of the first functional layer 20 of the fourth region 86) of the portion of the first adhesive layer 81 arranged on the surface of the first functional layer 20 on the second side of the first groove 21 is 1 mm to 5 mm, for example, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, etc.

[0134] The widths w31 and w32 may be the same or different. The total width of the first adhesive layer 81 in the length direction of the first functional layer 20 is approximately equal to the sum of w31, the width of the first groove 21 in the length direction of the first functional layer 20, and w32.

[0135] In one possible embodiment, the first region 30 has both opposing end edges that are respectively in the same plane as the opposing opposite edges of the first functional layer 20, and as shown in Figures 11 and 12, the length of any one of the first regions 30 in the width direction of the first functional layer 20 is equal to the length of the first functional layer 20 in which the first region 30 is arranged, for example, the length of the first region 30 arranged on both opposing sides (first side and second side) of the first groove 21 is equal to the width of the portion of the first functional layer 20 arranged on both opposing sides of the first groove 21.

[0136] The length direction of the first functional layer 20 is also the length direction of the first current collector 10, the width direction of the first functional layer 20 is also the width direction of the first current collector 10, and the width of the first current collector 10 is approximately equal to the maximum width of the first functional layer 20 (i.e., the width of the portions located on both opposing sides of the first groove 21 of the first functional layer 20 in Figures 11 and 12).

[0137] In one possible embodiment, as shown in FIG. 11, at least one end of the first current collector 10 may have a first empty foil region 11 in which the first functional layer 20 is not disposed.

[0138] An embodiment of the present application further provides a battery comprising a first plate, a separator, and a second plate of opposite polarity to the first plate, stacked in series, the first plate comprising the plate described above.

[0139] In one possible embodiment, the battery comprises a battery cell including a first electrode plate, a separator, and a second electrode plate which are stacked in sequence. Specifically, the battery cell may be a wound-type battery cell formed by stacking the first electrode plate, the separator, and the second electrode plate in sequence and then winding them up. Here, the first electrode plate / separator / second electrode plate are wound along the length direction to form the wound-type battery cell. When forming the wound-type battery cell, the first electrode plate, the separator, and the second electrode plate each have a folded portion and a straight portion connected to both ends of each folded portion, and the direction from one folded portion to the other folded portion is parallel to the length direction of the wound-type battery cell, and the direction from one straight portion to the other straight portion is parallel to the width direction of the wound-type battery cell.

[0140] The separator serves to isolate the first and second electrodes so that they do not come into contact with each other and cause a short circuit. The thickness of the separator is 5 to 16 μm, and may be, for example, 5 μm, 8 μm, 10 μm, 13 μm, 16 μm, etc., and the separator may be a conventional separator in the field, including, for example, a substrate or a coated separator in which a coating is applied onto a substrate.

[0141] In one possible embodiment, the second plate comprises a second current collector and a second functional layer 92 on the surface of the second current collector, the second plate having opposite ends (referred to as the fifth end and the sixth end, respectively), at least one end of the second plate has a second blank foil area 93 where no coating is provided, and in addition to the second blank foil area 93, the remaining part of the second plate is provided with the second functional layer 92. The contact area between the second functional layer 92 and the second blank foil area 93 usually has a concave-convex structure, and in order to avoid scratching the separator and improve the safety performance of the battery, a second adhesive layer 82 may be provided on at least one end of the second plate in the part covered by the first plate, where the part of the second plate covered by the first plate is usually also the part of the second plate covered by the separator. The second functional layer 92 is the active material layer of the second plate.

[0142] As shown in FIG. 13 , a second adhesive layer 82 is provided in the area covered by the first plate at one end (the fifth end) of the second plate, and the number of first regions 30 of the first plate corresponding to the second adhesive layer 82 is x, where 0≦x≦20, x is, for example, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20.

[0143] In one possible embodiment, as shown in Figures 11 and 12, the first plate has opposite ends (referred to as the third end and the fourth end, respectively), and has a first end covering region 22 at one end (the third end), the first end covering region 22 corresponds to the position of the second adhesive layer 82 of the second plate, i.e., the first end covering region 22 and the second adhesive layer 82 cover each other (the projection of the second adhesive layer 82 on the first plate approximately overlaps with the first end covering region 22), the width W4 of the first end covering region 22 in the length direction of the first plate / second plate is equal to the width W6 of the second adhesive layer 82 in the length direction of the first plate / second plate, and x number of first regions 30 are present in the first end covering region 22.

[0144] In some embodiments, the width w6 of the second adhesive layer 82 in the length direction of the second plate is between 3 mm and 5 mm, for example, w6 is 3 mm, 3.5 mm, 4 mm, 4.5 mm, or 5 mm.

[0145] As shown in FIG. 13, the second adhesive layer 82 covers at least a portion of the second empty foil area 93 and extends from the second empty foil area 93 to the surface of the second functional layer 92 .

[0146] Furthermore, as shown in Figures 11 to 13, the first electrode plate has, at its other end (fourth end), a second end covering region 23 that covers the other end (sixth end) of the second electrode plate, i.e., the projection of the sixth end of the second electrode plate on the first electrode plate is located in the second end covering region 23 and does not extend beyond the second end covering region 23, and the sixth end of the second electrode plate does not have a blank foil region (i.e., the second functional layer 92 and the outer edge of the second current collector are at the same height), and the second adhesive layer 82 does not need to be provided.

[0147] In some embodiments, the width w5 of the second edge covering region 23 in the length direction of the first plate is 3 to 5 mm, for example 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, etc.

[0148] No. A third adhesive layer is provided on the surface of the second electrode plate corresponding to the first electrode tab 91 / first groove 21 position of the first electrode plate, and the projection of the third adhesive layer on the first electrode plate can be made to cover the first groove 21 to further prevent lithium deposition in the negative electrode.

[0149] The first projection of the third adhesive layer on the first electrode plate covers at least one first region 30, and the portion of the first projection located on the first side of the first groove 21 covers 0 to 8 first regions 30, for example, 0, 1, 2, 3, 4, 5, 6, 7, 8, etc., a number of first regions 30 equal to or not equal to a1; the portion of the first projection located on the second side of the first groove 21 covers 0 to 8 first regions 30, for example, 0 The condition that the first projection covers a number of first regions 30 equal to or unequal to a2, such as 1, 2, 3, 4, 5, 6, 7, 8, etc., and the condition that the portion of the first projection located on the third side of the first groove 21 covers 0 to 40 first regions 30, such as 0, 2, 5, 8, 10, 12, 15, 18, 20, 22, 25, 28, 30, 32, 35, 38, 40, etc., a number of first regions 30 equal to or unequal to a3, is satisfied.

[0150] In one possible embodiment, the width in the longitudinal direction of the first functional layer 20 in the portion located on the first side of the first groove 21 in the first projection is 1 mm to 5 mm, which may or may not be equal to w31, for example, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, etc., and the width in the longitudinal direction of the first functional layer 20 in the portion located on the second side of the first groove 21 in the first projection is 3 mm to 5 mm, which may or may not be equal to w32, for example, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, etc.

[0151] In one possible embodiment, the first projection of the third adhesive layer on the first plate covers or is covered by the first adhesive layer 81, the first projection and the first adhesive layer 81 for example overlapping.

[0152] In one possible embodiment, the second plate is provided with a second electrode tab, and the first electrode tab 91 does not overlap with the second electrode tab in the width direction of the battery cell, i.e., the projection of the first electrode tab 91 perpendicular to the width direction of the battery cell does not overlap with the projection of the second electrode tab perpendicular to the width direction of the battery cell.

[0153] In some embodiments, the second functional layer 92 is provided with a second groove 921 and a fourth adhesive layer 84 covering the second groove 921, and at least a portion of the second electrode tab is disposed in the second groove 921 and covered by the fourth adhesive layer 84 (i.e., the portion of the second electrode tab disposed in the second groove 921 is not covered by the fourth adhesive layer 84). 4 Adhesive layer 84 covered by

[0154] In one possible embodiment, the second groove 921 functions as an electrode tab groove for positioning an electrode tab, with at least a portion of its bottom surface area being the surface of the second current collector (i.e., a portion of its bottom surface area is exposed from the second current collector), and the second electrode tab may be connected to the second current collector exposed at the bottom surface of the second groove 921, or more specifically, may be welded onto the second current collector exposed at the bottom surface of the second groove 921.

[0155] As shown in FIG. 13, the second plate may have an electrode tab center position structure, that is, the second electrode tab may be located in the center of the second plate rather than at the end.

[0156] In one possible embodiment, at least both sides of the second groove 921 are the second functional layer 92. In some embodiments, as shown in FIG. 13, on a plane perpendicular to the thickness direction of the second current collector, the second groove 921 has one side flush with one long side of the second current collector and the remaining side surrounded by the second functional layer 92, i.e., the second groove 921 has an opening facing one long side of the second current collector, and when a second electrode tab is provided, one end of the second electrode tab can extend from the outer edge of the second current collector through the opening, specifically, the second electrode tab can extend from the outer edge of the second current collector through the opening along its length, and the part of the second electrode tab arranged in the second groove 921 (i.e., the part not extending from the outer edge of the first current collector 10) may be covered by the second adhesive layer 82. The length direction of the second electrode tab is parallel to the width direction of the second electrode plate.

[0157] As shown in FIG. 13, the projection of the second groove 921 onto the second current collector is a rectangle, one short side of which is in the same plane as one long side of the second current collector, and the remaining three sides are surrounded by the second functional layer 92.

[0158] In one possible embodiment, the fourth adhesive layer 84 extends to the surface of the second functional layer 92 around the second groove 921 and is adhered to the second functional layer 92 around the second groove 921.

[0159] In one possible embodiment, the second groove 921 has a fourth side, a fifth side, and a sixth side, and the direction from the fourth side to the fifth side is parallel to the length direction of the second plate; the projection of the fourth adhesive layer 84 on the first plate covers at least one first region 30; and the projection of the portion of the fourth adhesive layer 84 arranged on the fourth side of the second groove on the first plate covers 0 to 8 first regions 30, for example, 0, 1, 2, 3, 4, 5, 6, 7, or 8, a number of first regions 30 equal to or not equal to a1. The following conditions are satisfied: the projection of the portion of the fourth adhesive layer 84 arranged on the sixth side of the second groove on the first electrode plate covers 0 to 8 first regions 30, for example, 0, 1, 2, 3, 4, 5, 6, 7, or 8, a number of first regions 30 equal to or unequal to a2; and the projection of the portion of the fourth adhesive layer 84 arranged on the sixth side of the second groove on the first electrode plate covers 0 to 40 first regions 30, for example, 0, 2, 5, 8, 10, 12, 15, 18, 20, 22, 25, 28, 30, 32, 35, 38, or 40, a number of first regions 30 equal to or unequal to a3.

[0160] In one possible embodiment, the width of the portion of the fourth adhesive layer 84 arranged on the fourth side of the second groove in the length direction of the second electrode plate may be equal to or unequal to w31, between 1 mm and 5 mm, for example, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, or 5 mm, and the width of the portion of the fourth adhesive layer 84 arranged on the fifth side of the second groove in the length direction of the second electrode plate may be equal to or unequal to w32, between 3 mm and 5 mm, for example, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, or 5 mm.

[0161] In one possible embodiment, the second groove 921 may have parameters such as shape and dimensions that are the same as or different from the first groove 21, and the fourth adhesive layer 84 may have parameters such as shape and area that are the same as or different from the first adhesive layer 81.

[0162] The above first adhesive layer 81, second adhesive layer 82, third adhesive layer, and fourth adhesive layer 84 may each have a thickness of 10 to 16 μm, for example, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, 15 μm, 16 μm, etc., and specifically, these may be adhesive papers.

[0163] In addition, when the above-mentioned one adhesive layer (or its projection) covers the first region 30, it means that in the length direction of the first functional layer 20, both opposing sides of the first region 30 covered by the adhesive layer are within the projection of the adhesive layer on the surface of the first functional layer 20 (i.e., the first region 30 covered by the adhesive layer does not extend beyond the outer edge of the projection of the adhesive layer on the surface of the first functional layer 20), while in the width direction of the first functional layer 20, the first region 30 covered by the adhesive layer may be partially within the projection of the adhesive layer on the surface of the first functional layer 20 and partially outside the projection of the adhesive layer on the surface of the first functional layer 20, or the entire first region 30 may be within the projection of the adhesive layer on the surface of the first functional layer 20.

[0164] For example, as shown in Figures 11 and 12, the first adhesive layer 81 covers four first regions 30, and in the length direction of the first functional layer 20, both opposing sides of the four first regions 30 are within the projection of the first adhesive layer 81 on the surface of the first functional layer 20, while in the width direction of the first functional layer 20, the four first regions 30 extend partially within the projection of the first adhesive layer 81 on the surface of the first functional layer 20 and partially outside the projection of the first adhesive layer 81 on the surface of the first functional layer 20.

[0165] The above battery may include a lithium ion battery, and may be manufactured by a conventional method in the field, and the manufacturing process generally includes steps of winding, encapsulation, liquid injection, degradation, formation, secondary encapsulation, sorting, packaging, etc. For example, a first electrode plate, a separator, and a second electrode plate are stacked and arranged, then wound to form a bare battery cell, the bare battery cell is placed in an exterior foil (such as aluminum plastic film), and an electrolyte is injected into the battery cell, vacuum encapsulation, standing, formation (charging at a constant current of 0.1C to 4% SOC (state of charge), then charging at a constant current of 0.2C to 10% SOC), shaping, etc., to manufacture a soft-pack lithium ion battery.

[0166] In order to explain the electrode plate provided by the present application, the improvement can be achieved to improve the initial charge / discharge efficiency of the battery and to improve the battery expansion, and the following test was carried out on the manufactured electrode plate.

[0167] Test 1: Test of surface aspects of first region 30 and second region 40

[0168] The images were taken using a scanning electron microscope (SEM) at 500x-1.0kx magnification, with the SEM image shown in FIG. 2 at 50x magnification, and the widths of the first region 30 and second region 40 measured by locating them with a ruler.

[0169] Here, the spacing between adjacent second regions 40, i.e. the width of the first region 30, is described, and the measurements at H1, H2, and H3 in the figure are described as being H1=537 μm, H2=372 μm, H3=416 μm.

[0170] Here, the spacing between adjacent first regions 30, i.e. the width of second region 40, is described, and the measurements at H4 and H5 in the figure are described as being H4=267 μm, H5=279 μm.

[0171] Test 2: Test of the cross-sectional aspects of the first region 30 and the second region 40

[0172] An ion milling (Cross section polisher, CP) device is used to sputter the electrode plate provided by the present application, and a cross section is obtained and photographed using a scanning electron microscope (SEM) at a magnification of 500x-1.0kx. As shown in FIG. 3, FIG. 3 is an SEM image of the second region 40 at a magnification of 3.0kx, and as shown in FIG. 4, FIG. 4 is an SEM image of the first region 30 at a magnification of 3.0kx.

[0173] As can be seen from Figures 3 and 4, the volume of the pores 70 in the first region 30 is smaller than the volume of the pores 70 in the second region 40, which indicates that some of the pores 70 in the first functional layer 20 are filled with the inorganic salt layer 50.

[0174] Test 3: Testing the elemental content of the first region 30 and the second region 40

[0175] For the location of the photograph collected by SEM, a test analysis was performed using an X-ray energy spectrometer (abbreviated as EDS), as shown in FIG. 5, which is a line scan EDS image of an electron microscope image at 500 times, and as shown in FIG. 6, which is a test enlargement of the local location indicated by the dotted frame in FIG. 5.

[0176] Test 4: Cycle test and expansion test

[0177] Next, cycle tests and expansion tests were conducted on the batteries of the two comparison groups and the two experimental groups, and the only difference between the batteries used in the two comparison groups and the batteries used in the two experimental groups was that the batteries used in the two experimental groups used the electrode plate provided by the present application as the first electrode plate, while the batteries used in the comparison group used a conventional first electrode plate that did not contain metallic lithium.

[0178] The test process includes steps 1 to 10: In step 1, the battery is left in a temperature environment of 5°C ± 2°C for 10 minutes. In step 2, the battery is discharged to the lower limit voltage at a discharge rate of 0.2C and left for 10 minutes. In step 3, charge the battery to the upper voltage limit at a battery charge rate of 0.7C, cut off at 0.05C, and leave it for 10 minutes. In step 4, the battery is discharged at a 0.2C discharge rate to the lower limit voltage to perform an initial capacity test. In step 5, leave the battery for 10 minutes. Step 6: Charge the battery to the upper voltage limit at 3C battery charge rate, cut off at 0.05C, measure the thickness of the battery, In step 7, the battery is left in a 25°C ± 2°C environment for 10 minutes. In step 8, discharge the battery to the lower limit voltage at a discharge rate of 1C and leave it for 10 minutes. In step 9, charge the battery to the upper voltage limit at 3C, cut off at 0.05C, and leave it for 10 minutes. Steps 10Then, cycle steps 8 and 9 1000 times, measure the thickness of the battery in a fully charged state after every 50 cycles among 0 to 200 cycles, measure the thickness of the battery in a fully charged state after every 100 cycles among 200 to 1000 cycles, and perform a capacity test by repeating steps 3 and 4 in a temperature environment of 25°C. After 1000 cycles, measure the thickness of the battery in a fully charged state.

[0179] Test 5, Capacity Test

[0180] same theory Batteries of different capacities were prepared, and four experimental group batteries with different target capacities and one comparative group battery were processed with different lithium refill surface densities. These batteries were placed in a constant temperature environment of 25°C, charged to 4.48V at a battery charging rate of 1C, constant current and constant voltage, and then cut off at 0.05C at a constant voltage, left for 5 minutes, and discharged to 3V at a battery discharging rate of 0.2C. The capacity data at 3V were compared, and the results are shown in Tables 1-4 below.

[0181] [Table 1]

[0182] [Table 2]

[0183] [Table 3]

[0184] [Table 4]

[0185] As can be seen from Tables 1 to 4, experimental groups 1 to 4 were In a group On the other hand, the 3V capacity has been significantly improved, reaching the design value in both cases.

[0186] As can be seen intuitively from Tables 1 to 4, the initial charge / discharge efficiency of the batteries according to the experimental group is higher than that of the corresponding comparative group, which indicates that the present invention can significantly improve the initial charge / discharge efficiency of the battery. Also, as can be seen intuitively from Tables 1 to 4, the volume expansion rate of the batteries according to the experimental group after 100 charge / discharge cycles is lower than that of the corresponding comparative group after 100 charge / discharge cycles, which indicates that the present invention can significantly improve the technical problem that the electrodes are prone to volume expansion.

[0187] The detection result of step 9 is shown in FIG. 10. As can be seen from FIG. 10, the abscissa indicates the number of charging cycles, and the ordinate indicates the expansion rate. Original Application Batteries provided by (The battery is the experimental group battery in FIG. 10, i.e., experimental group 1 battery in Table 1.) is a conventional battery (The battery is the comparative battery in FIG. 10, i.e., the comparative battery in Table 1.) The expansion rate in the fully charged state is lower than that of the battery shown in FIG. Original Application The battery provided by US Pat. No. 6,399,633 can reduce relative expansion during cycling by forming a silicate inorganic salt layer 50 in the first plate.

[0188] As shown in FIG. 9, the cycle performance of the battery provided by the present application and the conventional battery is compared. Capacity retention 9 is a curve comparison diagram, in which the ordinate indicates the battery capacity retention rate. As can be seen from FIG. Original Application Batteries provided by (The battery is the experimental group battery in FIG. 9, i.e., experimental group 1 battery in Table 1) After completing 450 charge-discharge cycles, the battery capacity was reduced to 80%, which is lower than that of conventional batteries. (The battery is the comparative battery in FIG. 9, i.e., the comparative battery in Table 1.) After completing 350 charge / discharge cycles, the battery capacity had decreased to 80%. Original Application The battery provided by the present invention has improved battery cycle performance by approximately 100 charge / discharge cycles, and the corresponding battery capacity retention rate has improved by approximately 5% to 15%. Original Application have shown that the improvement has resulted in a significant improvement in the battery capacity as well as in the cycle performance of the battery.

[0189] It should be noted that the numerical values ​​and numerical ranges in this application are approximate values, and there is a possibility that a certain range of error may occur due to the influence of the manufacturing process, but this error can be considered to be negligible by a person skilled in the art.

[0190] In the description of this application, it should be understood that the orientations or positional relationships indicated by the terms "center," "length," "width," "thickness," "top," "bottom," "up," "down," "left," "right," "front," "rear," "vertical," "horizontal," "inner," "outer," "axial," "circumferential," and the like are based on the orientations or positional relationships shown in the drawings, are intended only to facilitate and simplify the description of this application, and are not intended to indicate or suggest that the positions or elements shown must be in a particular orientation or constructed or operated in a particular structure, and therefore cannot be understood as limiting this application.

[0191] Additionally, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or suggesting the relative importance or implicitly indicating the number of technical features depicted. Thus, features qualified by "first" and "second" can explicitly or implicitly include one or more of the features. In the present description, "multiple" means at least two, e.g., two, three, etc., unless otherwise expressly and specifically limited.

[0192] This application claims priority to a Chinese patent application bearing application number 202210690099.7 and entitled "Electrode Plate and Battery" filed with the China Patent Office on June 17, 2022, and also claims priority to a Chinese patent application bearing application number 202221520256.1 and entitled "Electrode Plate and Battery" filed with the China Patent Office on June 17, 2022, the entire contents of which are incorporated herein by reference. [Explanation of symbols]

[0193] 10. First current collector 11. First empty foil area 20. First functional layer 21. First groove 22, first edge covering region 23, second edge covering region 30. The first area 40, The second area 50, inorganic salt layer 60, transition area 70, pore 80. Lithium band 81, first adhesive layer 82, second adhesive layer 84, 4th adhesive layer 85, Third Region 86, The Fourth Region 87, The Fifth Region 91, first electrode tab 92, second functional layer 921, the second groove 93, the second empty foil area

Claims

1. An electrode plate comprising a first current collector (10) and a first functional layer (20) provided on at least one surface of the first current collector (10), the first functional layer (20) containing active material particles, the first functional layer (20) having, on its surface, several first regions (30) and several second regions (40) alternately distributed with respect to the first regions (30), and an inorganic salt layer (50) is present outside a portion of the active material particles within the first regions (30).

2. 2. The plate of claim 1, wherein the porosity of the first region (30) is less than the porosity of the second region (40).

3. the porosity of said first region (30) is between 21% and 29%; and / or The plate of claim 2, wherein the porosity of the second region (40) is between 30% and 34%.

4. The inorganic salt layer (50) comprises at least one of lithium fluoride or lithium carbonate, lithium silicate, and / or 2. The plate of claim 1, wherein a mass percentage of the inorganic salt layer (50) in the first region (30) is greater than a mass percentage of the inorganic salt layer (50) in the second region (40).

5. the width of said first region (30) is between 100 μm and 4 mm; and / or 4. The plate according to claim 3, characterized in that the width of said second region (40) is between 0 μm and 4 mm.

6. 4. The plate of claim 3, wherein within said first region (30) the ratio of the content of elemental oxygen to elemental silicon is greater than 4:

1.

7. 7. The electrode plate according to claim 1, wherein in the first region (30), the ratio of the content of elemental fluorine to the content of elemental phosphorus is greater than 7:

1.

8. The electrode plate according to any one of claims 1 to 6, characterized in that in the second region (40), the ratio S1:S2 of the content of silicon element to the content of oxygen element satisfies 2:1≦S1:S2≦4:

1.

9. The electrode plate according to any one of claims 1 to 6, characterized in that, within the second region (40), the ratio S3:S4 of the content of fluorine and phosphorus in the first functional layer (20) satisfies 6:1≦S3:S4≦7:

1.

10. the active material particles comprise at least one of a silicon material and a silicon oxide material, and graphite, the mass of the silicon material and / or the silicon oxide material being 7% to 50% of the total mass of the active material particles; or the active material particles include a carbon material and graphite; or The electrode plate according to any one of claims 1 to 6, characterized in that the active material particles contain at least one of a silicon material and a silicon oxide material, and a carbon material, and the mass of the silicon material and / or the silicon oxide material accounts for 7% to 50% of the total mass of the active material particles.

11. the first region (30) forms a first angle with the width direction of the first functional layer (20) in the extension direction, the first angle being in the range of 0° to 45°; and / or the ratio of the total area of ​​the plurality of first regions (30) to the total area of ​​the second regions (40) is between 0.7:1 and 3:1; and / or The electrode plate according to claim 1, characterized in that, with respect to the surface of the first current collector (10), a portion of the first region (30) farthest from the first current collector (10) is higher than the second region (40), and a difference in height between the portion of the first region (30) farthest from the first current collector (10) and the portion of the second region (40) farthest from the first current collector (10) is 0.1 μm to 8 μm.

12. The electrode plate according to claim 11, further comprising a first electrode tab (91) and a first adhesive layer (81) formed on the surface of the first functional layer (20), the first functional layer (20) being provided with a first groove (21), at least a portion of the first electrode tab (91) being disposed in the first groove (21) and covered by the first adhesive layer (81), and the first adhesive layer (81) covering at least one of the first regions (30).

13. The first groove (21) has a first side, a second side, and a third side, and the direction from the first side to the second side is parallel to the length direction of the first functional layer (20); The portion of the first adhesive layer (81) arranged on the surface of the first functional layer (20) on the first side of the first groove (21) covers 0 to 8 of the first regions (30), and / or The portion of the first adhesive layer (81) arranged on the surface of the first functional layer (20) on the second side of the first groove (21) covers 0 to 8 of the first regions (30), and / or The portion of the first adhesive layer (81) arranged on the surface of the first functional layer (20) on the third side of the first groove (21) covers 0 to 40 of the first regions (30), and / or The width of the portion of the first adhesive layer (81) arranged on the surface of the first functional layer (20) on the first side of the first groove (21) in the longitudinal direction of the first functional layer (20) is 1 mm to 5 mm, and / or The electrode plate according to claim 12, characterized in that the width of the portion of the first adhesive layer (81) arranged on the surface of the first functional layer (20) on the second side of the first groove (21) in the longitudinal direction of the first functional layer (20) is 1 mm to 5 mm.

14. A battery comprising a sealed case and a battery cell disposed inside the sealed case, the battery cell comprising a first plate and a second plate, the first plate being a plate according to any one of claims 1 to 13, and the polarity of the second plate being opposite to the polarity of the first plate.

15. A second adhesive layer (82) is provided in the area of ​​one end of the second plate covered by the first plate, and the number of the first areas (30) of the first plate corresponding to the second adhesive layer (82) is 0 to 20; and / or The second electrode plate comprises a second current collector and a second functional layer (92) provided on a surface of the second current collector, one end of the second electrode plate has a second empty foil area (93) where the second functional layer (92) is not provided, and the second adhesive layer (82) covers at least a portion of the second empty foil area (93) and extends from the second empty foil area (93) to the surface of the second functional layer (92), and / or 15. The battery of claim 14, wherein the width of the second adhesive layer (82) in the length direction of the second plate is between 3 mm and 5 mm.

16. The first functional layer (20) is provided with a first groove (21), and a third adhesive layer is provided on the surface of the second electrode plate at a position corresponding to the position of the first groove (21), and / or The battery of claim 15, characterized in that the second plate comprises a second current collector and a second functional layer (92) provided on a surface of the second current collector, the second functional layer (92) having a second groove (921) and a fourth adhesive layer (84) covering the second groove (921), and the second plate is provided with a second electrode tab, at least a portion of the second electrode tab being disposed in the second groove (921) and covered by the fourth adhesive layer (84).

17. the first groove (21) has a first side, a second side, and a third side, a first projection of the third adhesive layer on the first plate covers at least one of the first regions (30); and the part of the first projection located on the first side of the first groove (21) covers 0 to 8 of the first regions (30); and / or the part of the first projection located on the second side of the first groove (21) covers 0 to 8 of the first regions (30); and / or The condition is satisfied that the part of the first projection located on the third side of the first groove (21) covers 0 to 40 of the first regions (30); and / or the second groove (921) has a fourth side, a fifth side, and a sixth side, the projection of the fourth adhesive layer (84) on the first electrode plate covers at least one of the first regions (30), and the projection of the portion of the fourth adhesive layer (84) arranged on the fourth side of the second groove (921) on the first electrode plate covers 0 to 8 of the first regions (30); and / or the projection of the portion of the fourth adhesive layer (84) located on a fifth side of the second groove (921) on the first plate covers 0 to 8 of the first regions (30); and / or The battery of claim 16, characterized in that the projection of the portion of the fourth adhesive layer (84) arranged on the sixth side of the second groove (921) onto the first plate covers 0 to 40 of the first regions (30).

Images