Solid-state battery processing method

Abstract

The invention relates to the technical field of solid-state batteries, and discloses a solid-state battery processing method. The solid-state battery comprises a negative plate and a positive plate, a solid-state electrolyte layer is arranged between the negative plate and the positive plate, the positive plate comprises a positive body and a positive tab arranged on one side of the positive body, at least one side, close to the positive tab, of the circumferential direction of the negative plate extends out of the positive body to form a to-be-glued area, and the positive tab extends out of the negative plate. The solid-state battery processing method comprises the following steps: placing a positive plate on a solid-state electrolyte layer; and the to-be-glued area is glued, the gluing starting point is located in the overlapping area, a supporting piece is formed after glue is cured, and the supporting piece can be arranged between the adjacent solid electrolyte layers. According to the solid-state battery processing method, the possibility of short circuit of the to-be-glued area is effectively reduced, and the safety and reliability of the solid-state battery are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of solid-state batteries, and in particular to a solid-state battery processing method. Background Art

[0002] All-solid-state batteries are batteries that use solid electrolytes. Generally, all-solid-state batteries use traditional pole pieces with a large negative pole and a small positive pole. Therefore, a glue-coating area is formed around the positive pole piece. The glue is coated in the glue-coating area and solidified to form a support to solve the problem of shear force between pole pieces caused by pressing during assembly, which causes rupture and short circuit.

[0003] In the prior art, uneven glue coating causes the glue layer to be too thick, causing the positive electrode sheet to bulge out locally. This will result in poor contact between the positive electrode sheet and the adjacent solid electrolyte after subsequent battery cell stacking, causing an increase in lithium ion transfer impedance.

[0004] Therefore, a solid-state battery processing method is urgently needed to solve the above problems. Summary of the invention

[0005] Based on the above, the purpose of the present invention is to provide a solid-state battery processing method, which effectively reduces the possibility of short circuit in the area to be coated with glue and improves the safety and reliability of the solid-state battery.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A solid-state battery processing method, wherein the solid-state battery comprises a negative electrode sheet and a positive electrode sheet, wherein a solid electrolyte layer is arranged between the negative electrode sheet and the positive electrode sheet, wherein the positive electrode sheet comprises a positive electrode body and a positive electrode ear arranged on one side of the positive electrode body, wherein at least one side of the circumference of the negative electrode sheet close to the positive electrode ear extends out of the positive electrode body to form a region to be coated with glue, wherein the positive electrode ear extends out of the negative electrode sheet and is provided with an overlapping region penetrating the region to be coated with glue, wherein the solid-state battery processing method comprises:

[0008] placing the positive electrode sheet on the solid electrolyte layer;

[0009] Glue is applied to the area to be coated, and the starting point of the coating is located in the overlapping area. After the glue is cured, a support member is formed, and the support member can be placed between adjacent solid electrolyte layers.

[0010] The beneficial effects of the present invention are:

[0011] The solid-state battery of the present invention comprises a negative electrode sheet and a positive electrode sheet, a solid electrolyte layer is arranged between the negative electrode sheet and the positive electrode sheet, and the positive electrode sheet comprises a positive electrode body and a positive electrode ear, wherein the negative electrode sheet extends the positive electrode body at least on one side close to the positive electrode ear in the circumferential direction to form a region to be coated with glue, and the positive electrode ear is arranged in the region to be coated with glue and extends the negative electrode sheet. When processing the above-mentioned solid-state battery, the positive electrode sheet is first placed on the solid electrolyte layer, and then the glue is applied to the region to be coated with glue, and the glue application is used to form a support member after the glue is cured, and when the solid-state battery is finally pressed to form the solid-state battery, the support member can play a certain supporting role on the solid electrolyte layer, so as to avoid the solid electrolyte layer exceeding the positive electrode sheet part during the pressing and causing a short circuit. Specifically, since the active material layer is not arranged at the positive electrode ear position, the thickness is relatively thin, so the starting point of the glue application is set in the overlapping area during the glue application process, so that even if the local glue layer is uneven, it will not cause a large protrusion to the overlapping area, and then after stacking, there will be no problem of poor contact between the positive electrode sheet and the adjacent solid electrolyte layer, and at the same time, it will not cause the problem of increased lithium ion transmission impedance. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without paying any creative work.

[0013] Figure 1 It is a schematic diagram of the relationship between the negative electrode sheet, positive electrode sheet, solid electrolyte layer and the area to be coated with glue for a solid-state battery;

[0014] Figure 2 It is a schematic diagram of applying glue to the circumference of the positive electrode sheet in a clockwise direction by using a solid-state battery processing method provided by a specific embodiment of the present invention;

[0015] Figure 3 It is a flow chart of a solid-state battery processing method provided in a specific embodiment of the present invention.

[0016] In the figure:

[0017] 101, area to be coated; 102, overlapping area; 110, negative electrode sheet; 120, positive electrode sheet; 121, positive electrode body; 122, positive electrode ear; 130, solid electrolyte layer;

[0018] 200, glue gun;

[0019] 300. Scraper. DETAILED DESCRIPTION

[0020] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0021] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions.

[0022] Unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0023] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0024] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0025] like Figure 1-Figure 3As shown, this embodiment provides a solid-state battery processing method, the solid-state battery includes a negative electrode sheet 110 and a positive electrode sheet 120, a solid electrolyte layer 130 is arranged between the negative electrode sheet 110 and the positive electrode sheet 120, the positive electrode sheet 120 includes a positive electrode body 121 and a positive electrode ear 122 arranged on one side of the positive electrode body 121, the negative electrode sheet 110 extends the positive electrode body 121 on at least one side close to the positive electrode ear 122 to form a region to be coated with glue 101, the positive electrode ear 122 extends a negative electrode collector 140, and an overlapping region 102 is provided that penetrates the region to be coated with glue 101, the solid-state battery processing method includes: placing the positive electrode sheet 120 on the solid electrolyte layer 130; coating the region to be coated with glue 101, and the starting point of the coating is located in the overlapping region 102, and a support member is formed after the glue is cured, and the support member can be located between adjacent solid electrolyte layers 130.

[0026] The solid-state battery includes a negative electrode sheet 110 and a positive electrode sheet 120, a solid electrolyte layer 130 is arranged between the negative electrode sheet 110 and the positive electrode sheet 120, and the positive electrode sheet 120 includes a positive electrode body 121 and a positive electrode ear 122, wherein the negative electrode sheet 110 extends the area of ​​the positive electrode body 121 on at least one side close to the positive electrode ear 122 to form a region to be coated with glue 101, and the positive electrode ear 122 penetrates the region to be coated with glue 101 and extends the negative electrode sheet 110. When processing the above-mentioned solid-state battery, firstly, the positive electrode sheet 120 is placed on the solid electrolyte layer 130, and at this time, the negative electrode sheet 110 extends the positive electrode body 121 at least on one side close to the positive electrode ear 122 in the circumferential direction; then glue is applied to the area to be glued 101, and the glue application is used to form a support member after the glue is cured, and when the solid-state battery is finally pressed, the support member can play a certain supporting role for the solid electrolyte layer 130, so as to prevent the solid electrolyte layer 130 from breaking and short-circuiting when the part that exceeds the positive electrode sheet 120 is pressed. Specifically, since there is no active material layer at the position of the positive electrode ear 122 and the thickness is relatively thin, the starting point of the glue application is set at the overlapping area 102 during the glue application process, so that even if the local glue layer is uneven, it will not cause a large protrusion to the overlapping area 102, and then after stacking, there will be no problem of poor contact between the positive electrode sheet 120 and the adjacent solid electrolyte layer 130, and at the same time, it will not cause the problem of increased lithium ion transmission impedance.

[0027] Specifically, the positive electrode sheet 120 includes a positive electrode current collector and a positive electrode active material layer. The positive electrode ear 122 can be formed by cutting the positive electrode current collector or can be a separate conductive member. The positive electrode ear 122 is used to transmit the current of the battery cell. Exemplarily, the thickness of the positive electrode ear 122 ranges from 8μm to 16μm; the positive electrode active material layer is provided on the two opposite surfaces of the positive electrode current collector, so the thickness of the positive electrode active material layer ranges from 70μm to 500μm. That is, the thickness of the positive electrode ear 122 is much smaller than the thickness of the positive electrode active material layer, so the starting point of the glue coating falls on the overlapping area 102, which can effectively avoid causing local protrusion of the active material area; at the same time, the starting point of the glue coating is located in the overlapping area 102, and the positive electrode ear 122 can also be supported to avoid the problem of the positive electrode ear 122 breaking due to the thin positive electrode ear 122 during pressing.

[0028] Furthermore, there is no particular limitation on the positive electrode current collector, as long as it has conductivity and does not cause adverse chemical changes in the battery, and for example, stainless steel, aluminum, nickel, titanium, fired carbon, or aluminum or stainless steel surface-treated with one of carbon, nickel, titanium, silver, etc. can be used. The positive electrode active material layer includes a positive electrode active material, and the positive electrode active material includes a nickel-cobalt-manganese ternary material, a lithium iron phosphate material, a lithium manganese iron phosphate material, etc. The negative electrode sheet 110 includes a negative electrode current collector and a negative electrode active material layer. The negative electrode current collector can be made of copper, stainless steel, nickel, titanium, etc. The negative electrode active material layer includes a negative electrode active material, and the negative electrode active material includes artificial graphite, natural graphite, silicon-based materials, etc. Solid electrolytes include sulfides, oxides, and polymer solid electrolytes; specifically, the sulfide in the solid electrolyte can be Li7P3S11, Li3PS4 or 80Li2S-20P2S5; the polymer solid electrolyte can include polyethylene oxide PEO, polyacrylonitrile PAN, polyvinylidene fluoride PVDF, polymethyl methacrylate PMMA, polypropylene oxide PPO, polyvinylidene chloride PVDC, etc.; the oxide solid electrolytes include lithium oxide, zirconium oxide, lanthanum oxide, etc.

[0029] In this embodiment, the circumference of the negative electrode sheet 110 extends out of the positive electrode body 121, and the end point of the glue coating is located at the overlapping area 102. Even if the glue layer is uneven at the end point, it will not cause a large protrusion to the overlapping area 102, and thus after stacking, there will be no problem of poor contact between the positive electrode sheet 120 and the adjacent solid electrolyte layer 130, and at the same time, it will not cause the problem of increased lithium ion transmission impedance.

[0030] Preferably, the end point of the glue coating is arranged to coincide with the starting point of the glue coating, so that the positive electrode tab 122 is also provided with a glue layer, thereby increasing the strength of the positive electrode tab 122 and preventing the positive electrode tab 122 from breaking during pressing.

[0031] Optionally, the ratio of the width of the support member along the direction in which the positive ear 122 extends out of the positive body 121 to the length of the positive ear 122 extending out of the positive body 121 is set to 0.01-0.3. Specifically, it can be set to 0.1, 0.15, 0.2, 0.25, etc. Exemplarily, the width of the support member is set to 0.1mm-8mm to avoid the width of the support member being too large and affecting subsequent overcurrent. It can be set to 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm, etc.

[0032] In one embodiment, the gluing includes: starting from the starting point located at the overlap area 102, gluing the area to be glued 101 in a clockwise or counterclockwise direction. That is, gluing is only performed along one direction to the area to be glued 101. This gluing method has better continuity of glue, so that the thickness of the support member after curing is more consistent.

[0033] In another embodiment, the gluing includes: starting from the starting point located in the overlap area 102, gluing the area to be glued 101 in clockwise and counterclockwise directions at the same time. That is, gluing is performed synchronously in two directions. This gluing method is more efficient. Optionally, both directions are 180° around the area to be glued 101, so that gluing can be completed in both directions at the same time.

[0034] Specifically, a glue gun 200 is used to apply glue to the area to be glued 101, and the glue gun 200 is connected to a glue supply device, or glue is stored in the glue gun 200. The glue outlet of the glue gun 200 is adapted to the width of the area to be glued 101. For example, the ratio of the width of the glue outlet to the area to be glued 101 is set in the range of 0.6-1, and can be specifically set to 0.7, 0.8, 0.9, etc., which is conducive to improving the consistency of the glue in the width direction of the area to be glued 101.

[0035] Further, the glue outlet of the glue gun 200 is at an angle to the glue-coated area 101, and is tilted toward the direction in which the glue gun 200 moves, so that the operator can observe the glue discharge from the glue outlet. Exemplarily, the angle is set to 10°C-80°C, specifically 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, etc., and the glue gun 200 moves at a preset speed to apply glue, ensuring that the support formed after the glue amount is cured can play a good supporting effect. Exemplarily, the preset speed is set to 40mm / s-200mm / s, specifically 50mm / s, 70mm / s, 90mm / s, 110mm / s, 130mm / s, 150mm / s, 170mm / s, 190mm / s, etc. It can be understood that the preset speed is related to the viscosity of the glue, and those skilled in the art can set it according to actual conditions, and no specific limitation is made here.

[0036] Preferably, after applying glue to the area to be glued 101 by the glue gun 200, the glue outside the area to be glued 101 is scraped off. Avoid the glue outside the area to be glued 101 from affecting the normal use of the solid-state battery. The outside of the area to be glued 101 includes the surface beyond the positive electrode sheet 120 and the side beyond the negative electrode current collector 140. Accordingly, the scraper 300 can be set to be L-shaped.

[0037] Exemplarily, the outer diameter of the support member is not larger than the outer diameter of the solid electrolyte layer 130, so as to prevent the support member from extending beyond the edge of the negative electrode sheet 110 and taking up extra space. If the support member is folded over to reach the back side of the negative electrode sheet 110, it will also cause poor contact between the negative electrode sheet 110 and the adjacent positive electrode sheet 120, thereby affecting the normal use of the solid-state battery.

[0038] In this embodiment, after applying glue to the area to be coated 101 , the process further includes: curing to form a battery cell, that is, the battery cell includes a negative electrode sheet 110 , a positive electrode sheet 120 , a solid electrolyte layer 130 , and a support member located around the positive electrode sheet 120 .

[0039] Specifically, the glue is set as a solid electrolyte slurry, and the solid electrolyte slurry is made of the same material as the solid electrolyte layer 130, and plays a role in conducting lithium ions. It can be understood that the solid electrolyte slurry is consistent with the physical and chemical properties of the solid electrolyte layer 130 after curing, that is, the area to be glued 101 can be used as the solid electrolyte layer 130, which is conducive to improving the performance of the solid-state battery. The solid electrolyte slurry may include sulfide, oxide, and polymer solid electrolyte.

[0040] Exemplarily, the glue is set to be hot melt glue, and the curing time of the hot melt glue is about 3 seconds before the surface solidifies. After the surface solidifies, the battery cell monomer stacking operation can be performed, which improves the processing efficiency. Optionally, the hot melt adhesive can include polyolefin hot melt adhesive, ethylene and its copolymer hot melt adhesive, polyester hot melt adhesive, polyimide hot melt adhesive, polyurethane hot melt adhesive, styrene and its block copolymer hot melt adhesive, etc.

[0041] Finally, multiple battery cells are stacked in sequence to form a battery cell unit, and the battery cell unit is pressed at a preset pressure to form a solid-state battery. Optionally, the preset pressure is set to 400Mpa-800Mpa to ensure that the contact between the positive electrode sheet 120 and the negative electrode sheet 110 can meet the normal discharge of the solid-state battery. The number of battery cell units stacked and the preset pressure can be set by those skilled in the art according to actual needs, and are not specifically limited here.

[0042] It is worth noting that, under a preset pressure, the shrinkage rate of the plurality of support members is greater than or equal to the shrinkage rate of the battery cell unit, so as to prevent damage to the solid electrolyte layer 130 caused by insufficient shrinkage of the support members during the pressing process.

[0043] The above contents are only preferred embodiments of the present invention. For ordinary technicians in this field, according to the concept of the present invention, there will be changes in the specific implementation methods and application scopes. The content of this specification should not be understood as limiting the present invention.

Claims

1. A solid-state battery processing method, characterized in that: A solid-state battery comprises a negative electrode sheet (110) and a positive electrode sheet (120), wherein a solid electrolyte layer (130) is arranged between the negative electrode sheet (110) and the positive electrode sheet (120), wherein the positive electrode sheet (120) comprises a positive electrode body (121) and a positive electrode ear (122) arranged on one side of the positive electrode body (121), wherein at least one side of the negative electrode sheet (110) close to the positive electrode ear (122) in the circumferential direction thereof extends out of the positive electrode body (121) to form a region to be coated with glue (101), wherein the positive electrode ear (122) extends out of the negative electrode sheet (110) and is provided with an overlapping region (102) penetrating the region to be coated with glue (101), and wherein the solid-state battery processing method comprises: placing the positive electrode sheet (120) on the solid electrolyte layer (130); Glue is applied to the area to be coated (101), and the starting point of the coating is located at the overlapping area (102). After the glue is cured, a support member is formed, and the support member can be placed between adjacent solid electrolyte layers (130).

2. The solid-state battery processing method according to claim 1, characterized in that: The circumference of the negative electrode sheet (110) extends beyond the positive electrode body (121), and the end point of the glue coating is located at the overlapping area (102).

3. The solid-state battery processing method according to claim 2, characterized in that: The end point of gluing is set to coincide with the starting point of gluing.

4. The solid-state battery processing method according to claim 1, characterized in that: The ratio of the width of the support member along the direction in which the positive electrode tab (122) extends out of the positive electrode body (121) to the length of the positive electrode tab (122) extending out of the positive electrode body (121) is set to 0.01-0.

3.

5. The solid-state battery processing method according to claim 1, characterized in that: The glue coating comprises: Starting from the starting point located at the overlapping area (102), glue is applied toward the area to be glued (101) in a clockwise or counterclockwise direction.

6. The solid-state battery processing method according to claim 1, characterized in that: The glue coating comprises: Starting from the starting point located at the overlapping area (102), the area to be glued (101) is glued in clockwise and counterclockwise directions at the same time.

7. The solid-state battery processing method according to claim 1, characterized in that: A glue gun (200) is used to apply glue to the area (101) to be glued, and a glue outlet of the glue gun (200) is adapted to the width of the area (101) to be glued.

8. The solid-state battery processing method according to claim 7, characterized in that: The glue outlet of the glue gun (200) forms an angle with the area to be glued (101) and moves to apply glue at a preset speed, and after applying glue to the area to be glued (101) through the glue gun (200), the glue further comprises: scraping off the glue located outside the area to be glued (101).

9. The solid-state battery processing method according to claim 8, characterized in that: The angle is set to 10°C-80°C, and the preset speed is set to 40mm / s-200mm / s.

10. The solid-state battery processing method according to claim 1, characterized in that: The outer diameter of the support member is not greater than the outer diameter of the solid electrolyte layer (130).

11. The solid-state battery processing method according to claim 1, characterized in that: The glue is configured as a solid electrolyte slurry.

12. The solid-state battery processing method according to any one of claims 1 to 11, characterized in that: After applying glue to the circumference of the positive electrode sheet (120), the method further comprises: curing to form a battery cell monomer.

13. The solid-state battery processing method according to claim 12, characterized in that: A plurality of the battery cell monomers are stacked in sequence to form a battery cell unit, and the battery cell unit is pressed at a preset pressure to form the solid-state battery.

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