JP2022504655A - Secondary battery and its manufacturing method, electrode member and its manufacturing method, current collector manufacturing method - Google Patents

Abstract

The present invention provides a secondary battery and a method for manufacturing the same, an electrode member and a method for manufacturing the same, and a method for manufacturing a current collector. The electrode member includes an insulating substrate, a first conductive layer, and an active material layer, the first conductive layer is provided on the surface of the insulating substrate, and the active material layer is the insulating substrate of the first conductive layer. The first conductive layer is provided on the side far from the surface, and the first conductive layer is provided with a striped groove extending in the height direction. The tripe-shaped groove is used to release the stress of the first conductive layer. The secondary battery includes an electrode assembly including the electrode member.
[Selection diagram] FIG. 20

Description

The present invention relates to the field of batteries, and more particularly to a secondary battery and a method for manufacturing the same, an electrode member and a method for manufacturing the same, and a method for manufacturing a current collector.

The electrode member of the secondary battery generally includes a current collector and an active material layer applied to the surface of the current collector. In order to improve the safety performance of the secondary battery, a multi-layered current collector is selected for some of the electrode members, and as shown in FIGS. 1 to 3, the current collector includes the insulating substrate 11 and the insulating substrate 11. The active material layer 13 is coated on the surface of the conductive layer 12, including the conductive layer 12 connected to the surface of the insulating substrate 11.

In the process of manufacturing the electrode member, it is necessary to roll press the active material layer 13 so as to make the active material layer 13 thin and increase the energy density. The insulating substrate 11 is a relatively soft material (for example, PET plastic), but the conductive layer 12 is usually made of a metal material, and the elastic modulus of the insulating substrate 11 is smaller than the elastic modulus of the conductive layer 12, so that the insulating substrate 11 is used. The ductility of the conductive layer 12 is higher than the ductility of the conductive layer 12. In the process of spreading the insulating substrate 11, the insulating substrate 11 applies a force to the conductive layer 12, but since the connecting force between the insulating substrate 11 and the conductive layer 12 is small, when the conductive layer 12 is expanded to a certain extent, The conductive layer 12 may come off the surface of the insulating substrate 11 and affect the performance of the electrode member.

The present invention has been made in view of problems in the background technology, and is a secondary battery capable of reducing stress concentration, reducing the risk of the conductive layer coming off, and ensuring the performance of the electrode member, and a method for manufacturing the secondary battery. , An electrode member, a method for manufacturing the same, and a method for manufacturing a current collector.

In order to achieve the above object, the present invention provides an electrode member of a secondary battery.

The electrode member includes an insulating substrate, a first conductive layer, and an active material layer. The first conductive layer is provided on the surface of the insulating substrate, and the active material layer is provided on the side of the first conductive layer far from the insulating substrate. The first conductive layer is provided with a striped groove extending in the height direction.

The electrode member further includes a second conductive layer having a first portion located within the stripe groove.

The second conductive layer is provided on a surface of the first conductive layer away from the insulating substrate, and further includes a second portion connected to the first portion, and the active material layer is provided. Is provided on the surface of the second portion away from the first conductive layer.

The first conductive layer includes a main body portion to which the active material layer is applied, and a protrusion extending from the main body portion to which the active material layer is not applied. The striped groove includes a first groove formed in the protrusion, and the second portion is at least partially located on a surface of the protrusion away from the insulating substrate.

The striped groove further includes a second groove formed in the main body portion, and the first concave groove and the second concave groove communicate with each other.

The electrode member is provided on the surface of the second portion away from the protrusion, and further includes a protective layer connected to the active material layer, and the first groove does not protrude from the protective layer. ..

The rigidity of the second conductive layer is smaller than the rigidity of the first conductive layer.

The striped groove penetrates the first conductive layer along the thickness direction, and the first portion of the second conductive layer is connected to the insulating substrate.

There are a plurality of the striped grooves, and the plurality of striped grooves are arranged at intervals in the width direction.

In order to achieve the above object, the present invention further provides a secondary battery. The secondary battery includes an electrode assembly including the electrode member.

In order to achieve the above object, the present invention further provides a method for manufacturing a current collector. In the method of manufacturing the current collector, a first conductive layer is formed by preparing an insulating substrate and fixing a conductive material to the surface of the insulating substrate, and the height of the first conductive layer is increased. Includes the provision of striped grooves extending in the direction.

The conductive material is fixed to the surface of the insulating substrate by a vapor phase growth method or electroless plating.

The method for producing a current collector further comprises applying the conductive slurry to a part of the surface of the first conductive layer and filling the striped grooves with the conductive slurry. A second conductive layer is formed after the conductive slurry is cured.

In order to achieve the above object, the present invention further provides a method for manufacturing an electrode member. As the method for manufacturing the electrode member, the current collector manufactured by the method for manufacturing the current collector is prepared, and a slurry containing an active material is applied to a part of the surface of the first conductive layer. The striped groove is filled with the slurry containing the active material, the active material layer is formed after the slurry containing the active material is cured, and the active material layer is roll-pressed. A plurality of spaces are provided by welding a metal foil material to a region of the conductive layer in which the active material layer is not applied, and removing a part of the metal foil material and a part of the current collector. It is provided with the conductive structure of the above and the formation of a plurality of electrically guided portions provided with intervals.

The method for manufacturing the electrode member further comprises applying a slurry containing an insulating material to a part of a region on the surface of the first conductive layer and forming a protective layer after the slurry containing the insulating material is cured. Be prepared. The protective layer is formed before welding the metal foil material.

In order to achieve the above object, the present invention further provides a method for manufacturing a secondary battery. In the method for manufacturing the secondary battery, a positive electrode member, a negative electrode member, and a diaphragm are prepared, and the positive electrode member, the diaphragm, and the negative electrode member are integrally wound to form an electrode assembly, and the positive electrode member and the above are described. At least one of the negative electrode members is manufactured by the method for manufacturing the electrode member, an adapter piece is prepared, a plurality of conductive structures of the electrode assembly are laminated and welded to the adapter piece, and a top cover plate is used. And an electrode terminal fixed to the top cover plate are prepared, the adapter piece is welded to the electrode terminal, a case is prepared, the electrode assembly is arranged in the case, and the top cover is provided. It comprises connecting a plate to the case.

In order to achieve the above object, the present invention provides yet another method for manufacturing an electrode member. The method for manufacturing the electrode member is to prepare the current collector manufactured by the method for manufacturing the current collector, and to apply a slurry containing an active material to a part of the surface of the second conductive layer. That is, after the slurry containing the active material is cured, the active material layer is formed and the active material layer is roll-pressed, and the second conductive layer of the first conductive layer is not coated. By welding a metal foil material to the region and removing a part of the metal foil material and a part of the current collector, a plurality of conductive structures with a space and a plurality of electric guides with a space are provided. It is provided with forming a part.

The method for manufacturing the electrode member is to apply a slurry containing an insulating material to a part of the surface of the second conductive layer, and then cure the slurry containing the insulating material to form a protective layer. , Further prepare. The protective layer is formed before welding the metal foil material.

In order to achieve the above object, the present invention provides yet another method for manufacturing a secondary battery. In the method for manufacturing the secondary battery, a positive electrode member, a negative electrode member, and a diaphragm are prepared, and the positive electrode member, the diaphragm, and the negative electrode member are integrally wound to form an electrode assembly, and the positive electrode member and the positive electrode member are formed. At least one of the negative electrode members is manufactured by the method for manufacturing another electrode member, and an adapter piece is prepared, and a plurality of conductive structures of the electrode assembly are laminated and welded to the adapter piece. And, a top cover plate and an electrode terminal fixed to the top cover plate are prepared, the adapter piece is welded to the electrode terminal, a case is prepared, and the electrode assembly is arranged in the case. The cover plate is connected to the case.

The present application has the following beneficial effects. In the present application, since the striped groove is formed in the first conductive layer, the striped groove effectively releases the force applied to the first conductive layer, reduces the stress concentration, and is the first. The risk of the conductive layer coming off the surface of the insulating substrate can be effectively reduced, and the performance of the electrode member can be ensured.

It is a schematic diagram of the electrode member of the prior art. It is a schematic diagram in the process of roll-pressing the electrode member of FIG. It is a schematic diagram of the insulating base material and the conductive layer of the electrode member of FIG. 1 before roll pressing. It is a schematic diagram after the roll press of the insulating base material and the conductive layer of the electrode member of FIG. It is a schematic diagram of the secondary battery by this invention. It is sectional drawing of the electrode assembly by this invention. It is a schematic diagram of the 1st Example of the electrode member by this invention. It is sectional drawing which follows the line AA of FIG. It is a schematic diagram during molding of the electrode member of FIG. It is another schematic diagram during molding of the electrode member of FIG. 7. It is a schematic diagram after the roll press of the 1st conductive layer of FIG. It is still another schematic diagram during molding of the electrode member of FIG. 7. It is a schematic diagram after winding of the electrode member of FIG. It is a schematic diagram of the 2nd Example of the electrode member by this invention. FIG. 6 is a cross-sectional view taken along the line BB of FIG. It is a schematic diagram of the insulating substrate of FIG. 15 and the first conductive layer. It is a schematic diagram of the 3rd Example of the electrode member by this invention. FIG. 6 is a cross-sectional view taken along the line CC of FIG. It is a schematic diagram of the 4th Example of the electrode member by this invention. It is sectional drawing along the DD line of FIG. It is a schematic diagram of the 1st conductive layer of the electrode member of FIG. It is a schematic diagram of the 5th Example of the electrode member by this invention. FIG. 2 is a cross-sectional view taken along the line EE of FIG. 22. It is a schematic diagram of the 1st conductive layer of the electrode member of FIG.

The technical proposal in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the examples described are not all examples, but only some of the examples of the present application. The following description of at least one exemplary embodiment is merely exemplary in practice and is not intended to limit the present application and its uses or uses. All other embodiments obtained by one of ordinary skill in the art based on the embodiments of the present application without performing creative work are included in the scope of protection of the present application.

In the description of the present application, the use of terms such as "first" and "second" to limit parts is for facilitating the distinction of the parts, and unless otherwise specified, the above terms are used. Does not mean anything in particular and should not be construed as limiting the scope of protection of the present application.

The secondary battery of the present invention includes an electrode assembly, and the electrode assembly is provided between the positive electrode member 2, the negative electrode member 3, and the positive electrode member 2 and the negative electrode member 3, with reference to FIG. Includes diaphragm 4. The positive electrode member 2, the diaphragm 4, and the negative electrode member 3 are laminated and wound flat. The electrode assembly is a core component for realizing the charge / discharge function of the secondary battery.

The secondary battery of the present invention may be a soft pack battery in which an electrode assembly formed by winding a positive electrode member 2, a diaphragm 4, and a negative electrode member 3 is directly enclosed in a packaging bag. The packaging bag may be an aluminum plastic film.

Of course, the secondary battery of the present application may be a hard shell battery. Specifically, referring to FIG. 5, the secondary battery mainly includes an electrode assembly, a case 5, a top cover plate 6, an electrode terminal 7, and an adapter piece 8.

The case 5 may have a hexahedral shape or other shape. Inside the case 5, a cavity for accommodating the electrode assembly and the electrolytic solution is formed. The case 5 has an opening formed at one end, and the electrode assembly may be arranged in the storage chamber of the case 5 through the opening. The case 5 may be made of a conductive metal material such as aluminum or an aluminum alloy, or may be made of an insulating material such as plastic.

The top cover plate 6 is provided in the case 5 and covers the opening of the case 5, so that the electrode assembly is confined in the case 5. The electrode terminal 7 is provided on the top cover plate 6, the upper end of the electrode terminal 7 protrudes to the upper side of the top cover plate 6, and the lower end extends through the top cover plate 6 into the case 5. The adapter piece 8 is provided in the case 5 and fixed to the electrode terminal 7. The electrode terminal 7 and the adapter piece 8 are both two, the positive electrode member 2 is electrically connected to one electrode terminal 7 via one adapter piece 8, and the negative electrode member 3 is the other adapter piece 8. Is electrically connected to the other electrode terminal 7 via. The adapter piece 8 is welded to the electrode terminal 7.

In the secondary battery, an electrode member 1 described later is used for at least one of the positive electrode member 2 and the negative electrode member 3.

7 to 13 are schematic views of a first embodiment of the electrode member 1 according to the present invention. With reference to FIGS. 7 and 8, the electrode member 1 of the first embodiment includes an insulating substrate 11, a first conductive layer 12, and an active material layer 13. The first conductive layer 12 is provided on both sides of the insulating substrate 11, and the active material layer 13 is provided on the side far from the insulating substrate 11 of the first conductive layer 12.

The material of the insulating base material 11 may be a PET (polyethylene terephthalate) film or a PP (polypropylene) film.

The material of the first conductive layer 12 is at least one of a metal conductive material and a carbon-based conductive material, and the metal conductive material is aluminum, copper, nickel, titanium, silver, nickel-copper alloy, aluminum zirconium alloy. At least one of them is preferable, and the carbon-based conductive material is preferably at least one of graphite, acetylene black, graphene, and carbon nanotubes.

The first conductive layer 12 can be formed on the surface of the insulating substrate 11 by at least one of a vapor deposition method and an electroless plating method. Among them, in the vapor phase growth method, a physical vapor deposition (PVD), for example, a thermal vapor deposition method (Thermal Evaporation Deposition) is preferable.

The active material layer 13 can also be provided on the surface of the first conductive layer 12 by coating. The active material layer 13 is made of an active material such as lithium manganate and lithium iron phosphate, an adhesive, a conductive agent, and a solvent as a slurry, and then the slurry is applied to the outer surfaces of the two first conductive layers 12 to form a slurry. Can be formed by curing.

Referring to FIG. 9, the first conductive layer 12 is provided with a striped groove G extending substantially along the height direction Z and for releasing the stress of the first conductive layer 12. The length of the striped groove G along the width direction X is 0.001 mm to 1 mm, and is sufficiently shorter than the length of the striped groove G along the height direction Z. The striped groove G may be linear or curved, and may extend substantially along the height direction Z as a whole, that is, the extending direction and height of the striped groove G. There may be a small angle with the vertical direction Z (eg, the angle may be less than 10 °).

The thickness of the insulating substrate 11 can be 1 μm to 20 μm, and the thickness of the first conductive layer 12 can be 0.1 μm to 10 μm. Since the first conductive layer 12 is thin, burrs generated in the first conductive layer 12 when cutting the electrode member 1 are small, and it is difficult to break through the diaphragm 4 of a dozen μm, and it is safe to avoid a short circuit. Performance can be improved. Further, when the foreign matter breaks through the electrode member 1 of the secondary battery, the thickness of the first conductive layer 12 is small, so that the burr generated at the place where the foreign matter breaks through the first conductive layer 12 is small and breaks through the diaphragm 4. This makes it difficult to avoid short circuits and improve safety performance.

The first conductive layer 12 has a main body portion 121 coated with the active material layer 13 and a protrusion 122 extending from the main body portion 121 not coated with the active material layer 13. The active material layer 13 may be applied directly to the surface of the main body 121. Of course, as an alternative, another substance may be provided between the main body portion 121 and the active material layer 13.

The portion of the insulating substrate 11 corresponding to the protrusion 122 and the protrusion 122 form an electric guide portion P. The plurality of electric guide portions P may be arranged at intervals in the width direction X. With reference to FIG. 13, when the electrode member 1 is wound and molded, the plurality of electric guide portions P are laminated and arranged in the thickness direction Y.

The electrode member 1 further includes a protective layer 15 provided on the side of the protrusion 122 far from the insulating substrate 11 and connected to the active material layer 13.

The protective layer 15 contains an adhesive and an insulating material. The insulating material contains at least one of aluminum trioxide and aluminum oxyhydroxide. An adhesive, an insulating material and a solvent are mixed, applied to the surface of the protrusion 122, and cured to form a slurry forming the protective layer 15. The hardness of the protective layer 15 is larger than the hardness of the protrusion 122.

The electrode member 1 further includes a conductive structure 16 welded to a region not covered by the protective layer 15 of the protrusion 122. With reference to FIGS. 7 and 8, conductive structures 16 are fixed on both sides of each electric guide portion P along the thickness direction Y. Referring to FIG. 13, after the electrode member 1 is wound and molded, all the conductive structures 16 are laminated and provided, and are simultaneously welded to the adapter piece 8. Referring to FIG. 5, the current in the electrode member 1 can be output to the outside via the adapter piece 8 and the electrode terminal 7.

The electrode member 1 of the first embodiment can be molded by the following steps.

(1) A first conductive layer 12 is formed on the surface of the insulating base material 11 by a vapor phase growth method or an electroless plating method to prepare a composite tape material. As shown in FIG. 9, in the molding step, a striped groove G is previously formed in the first conductive layer 12.

(2) With reference to FIG. 10, the active material layer 13 and the protective layer 15 are simultaneously applied to the surface of the first conductive layer 12.

(3) The active material layer 13 is roll-pressed to consolidate the active material layer 13 and increase the density.

(4) With reference to FIG. 12, after roll pressing, a metal foil material (for example, aluminum foil) is welded to the first conductive layer 12, and then a plurality of electric guide portions P along the broken line in FIG. And the plurality of conductive structures 16 can be cut out to further obtain the electrode member 1 shown in FIG. 7.

In the step (1), the first conductive layer 12 can be formed on the surface of the insulating substrate 11 by a vapor phase growth method or an electroless plating method, so that between the first conductive layer 12 and the insulating substrate 11. The connecting force of the first conductive layer 12 is small, and the first conductive layer 12 may be easily peeled off from the surface of the insulating substrate 11 due to an external force.

Since the elastic modulus of the insulating substrate 11 is smaller than the elastic modulus of the first conductive layer 12, the ductility of the insulating substrate 11 is higher than the ductility of the first conductive layer 12. In the step (3), the insulating substrate 11 is pressurized and spread, and the insulating substrate 11 has high ductility. Therefore, the insulating substrate 11 applies a force to the first conductive layer 12. In the prior art, the force applied to the first conductive layer 12 cannot be released. Therefore, when the first conductive layer 12 is spread to a certain extent, the force applied to the first conductive layer 12 is applied to the insulating substrate 11 and the first. It becomes larger than the connection force between the conductive layer 12 of 1 and the insulating substrate 11 and the first conductive layer 12 slide relatively, the first conductive layer 12 comes off from the surface of the insulating substrate 11, and the electrode. It affects the performance of member 1.

In the present application, the striped groove G is formed in the first conductive layer 12, but the striped groove G effectively releases the force applied to the first conductive layer 12 and reduces the stress concentration. By avoiding that the force applied to the first conductive layer 12 is too large, the risk of the first conductive layer 12 coming off the surface of the insulating substrate 11 is effectively reduced, and the performance of the electrode member 1 is ensured.

Specifically, FIG. 11 shows a state in which the first conductive layer 12 is roll-pressed, and the broken line shows a state before the striped groove G is roll-pressed. In the roll press step of the step (3), the force applied to the first conductive layer 12 is gradually concentrated in the striped groove G, and when the force applied to the first conductive layer 12 is large, the first conductive layer 12 is applied. Since the layer 12 is torn along the striped groove G by a force, the stress is quickly released, and the force applied to the first conductive layer 12 is the connecting force between the insulating substrate 11 and the first conductive layer 12. It can be avoided that the size is larger, the probability that the insulating substrate 11 and the first conductive layer 12 slide relatively is reduced, and the performance of the electrode member 1 is ensured.

For the use of the secondary battery, the current generated in the active material layer 13 flows to the protrusion 122 via the main body 121, that is, the current flows in the first conductive layer 12 along the substantially height direction Z. Due to the flow, the overcurrent area of the first conductive layer 12 depends on the area of the cross section of the first conductive layer 12 perpendicular to the height direction Z. In the present application, the striped groove G extends substantially along the height direction Z, and the length in the width direction X is small. That is, the dimension of the striped groove G along the height direction Z is larger than the dimension of the striped groove G along the width direction X. Therefore, when the first conductive layer 12 is torn along the striped groove G in the process of being roll-pressed, the effect of the striped groove G on the overcurrent area of the first conductive layer 12 is small. As a result, the overcurrent capacity of the first conductive layer 12 can be sufficiently secured.

In the step (3), as the roll press progresses, the force applied to the first conductive layer 12 gradually increases, and the electrode member 1 has a constant length along the width direction X with reference to FIG. When the first conductive layer 12 is roll-pressed, the force applied to the first conductive layer 12 tears the first conductive layer 12 along the striped groove G, and the stress is quickly released. Since the first conductive layer 12 has a long length in the width direction X, it is preferable that the first conductive layer 12 has a plurality of striped grooves G and is arranged at intervals in the width direction X. The plurality of striped grooves G can release stress stepwise during the roll press, and the force applied to the first conductive layer 12 is larger than the connection force between the insulating substrate 11 and the first conductive layer 12. By avoiding the increase, the probability that the insulating substrate 11 and the first conductive layer 12 slide relatively is reduced, and the performance of the electrode member 1 is ensured.

Referring to FIGS. 8 and 9, the striped groove G penetrates the first conductive layer 12 in the thickness direction Y, that is, the depth of the striped groove G is in the thickness direction Y. It is equal to the thickness of the first conductive layer 12. At this time, the first conductive layer 12 is easily torn along the striped groove G during the roll press, and the stress is quickly released.

In the step (2), since the active material layer 13 can be filled in the striped groove G, a current on the active material layer 13 flows through the peripheral wall of the striped groove G to the first conductive layer 12. This makes it possible to improve the current collecting property of the first conductive layer 12. In the step (3), even if the first conductive layer 12 is torn along the striped groove G, the active material layer 13 is filled up to the torn portion by the force of the roll press.

Since the elastic modulus of the insulating substrate 11 is small, in the step (3), the insulating substrate 11 corresponding to the main body portion 121 extends to the lower side of the protrusion 122, and the insulating base 11 inside the protrusion 122 swells and deforms. The protrusion 122 is easily deformed by the acting force of the insulating substrate 11, and cracks are generated. On the other hand, in the present application, the protective layer 15 has high strength, gives a supporting force to the protrusion 122 in the process of roll-pressing the electrode member 1, regulates deformation of the protrusion 122, and cracks in the protrusion 122. Can be reduced and the overcurrent capacity of the electrode member 1 can be improved.

When the secondary battery is in operation, the protrusion 122 may come off due to vibration or the like. Therefore, by connecting the protective layer 15 to the active material layer 13, the protective layer 15 can be fixed to the active material layer 13 for protection. It is possible to increase the coupling force of the layer 15 to the electrode member 1 to enhance the seismic resistance and prevent the protective layer 15 from coming off together with the protrusion 122. At the same time, the protrusion 122 is most likely to swell near the root of the active material layer 13 (that is, the boundary between the protrusion 122 and the main body 121), so that when the protective layer 15 and the active material layer 13 are connected, the protrusion 122 is likely to swell. The deformation of the portion 122 can be reduced, the probability of cracking can be reduced, and the overcurrent capacity of the electrode member 1 can be improved.

Next, the other four embodiments will be described. For the sake of simplicity, in the following, only the parts of the other four embodiments that are different from the first embodiment will be mainly described, and the parts that are not explained will be referred to the first embodiment. I want you to understand.

14 to 16 are schematic views showing a second embodiment of the electrode member according to the present invention. Referring to FIGS. 14 and 16, the depth of the striped groove G is smaller than the thickness of the first conductive layer 12 along the thickness direction Y. The first conductive layer 12 of the second embodiment has a large overcurrent area as compared with the first embodiment. The cross section of the striped groove G may be U-shaped or V-shaped.

17 and 18 are schematic views showing a third embodiment of the electrode member according to the present invention. Referring to FIGS. 17 and 18, the electrode member 1 of the third embodiment has a second conductivity having a first portion 141 located in the striped groove G as compared with the first embodiment. Further includes layer 14. The first portion 141 is filled in the striped groove G, and the current around the striped groove G can be transmitted through the first portion 141. In other words, the first portion 141 can repair the conductive area of the first conductive layer 12, increase the overcurrent area, and secure the overall overcurrent capacity of the electrode member 1.

In the first embodiment, since the active material layer 13 is filled in the striped groove G, the distribution of the active material layer 13 is not uniform, that is, the thickness of the active material layer 13 in the striped groove G. The stripes are thicker than the thickness of other parts. During operation of the secondary battery, the active material layer 13 may elute lithium at a position corresponding to the striped groove G. In the third embodiment, the first portion 141 is filled in the striped groove G, so that the flatness of the first conductive layer 12 is ensured and the uniformity of the distribution of the active material layer 13 is improved. And the risk of lithium elution is reduced.

The second conductive layer 14 is provided on a surface of the first conductive layer 12 away from the insulating substrate 11, further includes a second portion 142 connected to the first portion 141, and the active material layer 13 is composed of the active material layer 13. The second portion 142 is provided on the surface away from the first conductive layer 12.

The second conductive layer 14 may be a metallic material or a non-metallic material. The second conductive layer 14 is preferably a non-metal material in which burrs are less likely to occur in order to reduce burrs generated when foreign matter penetrates the electrode member 1. Specifically, first, the conductive carbon, the adhesive and the solvent are made into a slurry, then the slurry can be applied to the first conductive layer 12 and the slurry can be cured to form the second conductive layer 14. .. During coating, the slurry is filled into the striped grooves G to form the first portion 141.

In the step (2), after the slurry of the second conductive layer 14 is applied to the first conductive layer 12, the slurry of the active material layer 13 and the slurry of the protective layer 15 are applied to the surface of the second conductive layer 14. It may be applied.

In the step (3), even if the first conductive layer 12 is torn along the striped groove G, the second portion 142 is filled up to the torn portion by the force of the roll press, whereby the first conductive layer 12 is torn. The conductive area of the layer 12 is repaired, the overcurrent area is increased, and the overall overcurrent capacity of the electrode member 1 is secured.

When the second conductive layer 14 is provided only on the surface of the first conductive layer 12, the current of the second conductive layer 14 is transmitted through the surface of the first conductive layer 12 to the first conductive layer 12. It is only conducted to. In the present application, since the first portion 141 of the second conductive layer 14 is embedded in the striped groove G of the first conductive layer 12, the first conductive layer 12 is interposed through the surface of the first conductive layer 12. By conducting not only the current to the layer 12 but also through the peripheral wall of the striped groove G, a plurality of conduction paths are increased, conductive areas are formed at a plurality of locations, and the conductivity performance of the electrode member 1 is improved. However, the polarization of the electrode member 1 and the secondary battery can be reduced, and the high-magnification charge / discharge performance of the secondary battery can be improved.

The second portion 142 is arranged at least in part on the surface of the protrusion 122 away from the insulating substrate 11. The protective layer 15 can be provided on the surface of the second portion 142 away from the protrusion 122. The conductive structure 16 is welded to a region not covered by the second portion 142 of the protrusion 122.

In the step (3), the main body portion 121 is spread by the insulating base material 11, but the protrusion 122 is hardly spread. The main body portion 121 and the insulating substrate 11 apply a force to the protrusion 122 at the time of spreading, but since the protrusion 122 is thin, the force causes microcracks in the protrusion 122. On the other hand, in the present application, since the second portion 142 is provided on the surface of the protrusion 122, even if a crack is generated in the process of roll-pressing the protrusion 122, the current in the crack is the second. It can flow to the outside through the portion 142, whereby the conductive area can be repaired and the overall overcurrent capacity of the electrode member 1 is ensured.

The rigidity of the second conductive layer 14 is lower than the rigidity of the first conductive layer 12. That is, the second conductive layer 14 is easily deformed when a force is applied. When the protrusion 122 is deformed, the second portion 142 is also deformed along with the protrusion 122, and even if the protrusion 122 is deformed too much and is torn, the second portion 142 is not torn and current transmission is ensured. To.

The striped groove G penetrates the first conductive layer 12 in the thickness direction Y, and the first portion 141 of the second conductive layer 14 is connected to the insulating substrate 11. The first portion 141 is fitted into the striped groove G and adhered to the insulating substrate 11 to increase the connection strength of the first conductive layer 12, the second conductive layer 14, and the insulating substrate 11.

19 to 21 are schematic views showing a fourth embodiment of the electrode member according to the present invention. With reference to FIGS. 19-21, the striped groove G of the fourth embodiment includes a first groove G1 formed in the protrusion 122 as compared to the third embodiment.

In the step (3), the portion corresponding to the main body portion 121 of the insulating substrate 11 is roll-pressed and spread, and the portion corresponding to the main body portion 121 of the insulating substrate 11 is the portion corresponding to the protrusion 122 of the insulating substrate 11. By applying a force to the insulating substrate 11, the portion corresponding to the protrusion 122 of the insulating substrate 11 is expanded. On the other hand, since the protrusion 122 is regulated by the protective layer 15, it can hardly be extended, and the portion of the insulating substrate 11 corresponding to the protrusion 122 exerts a force on the protrusion 122 at the time of spreading. When the force is larger than the connecting force between the insulating substrate 11 and the protrusion 122, the protrusion 122 is likely to come off from the insulating base 11. On the other hand, in the present application, the first concave groove G1 effectively releases the force applied to the protrusion 122, reduces the stress concentration, avoids the force applied to the protrusion 122 from becoming excessive, and causes the protrusion 122. The probability that the portion 122 will come off is effectively reduced, and the performance of the electrode member 1 is ensured.

Preferably, the first groove G1 does not protrude from the protective layer 15 in the direction away from the active material layer 13. Since the region covered by the protective layer 15 of the protrusion 122 receives the largest stress, the first groove G1 may be provided in the region covered by the protective layer 15 of the protrusion 122. On the other hand, the force applied to the region not covered by the protective layer 15 of the protrusion 122 is small and there is no risk of disengagement, but the first groove G1 extends to the region not covered by the protective layer 15 of the protrusion 122. Then, on the contrary, the overcurrent capacity of the protrusion 122 is reduced.

The striped groove G further includes a second groove G2 formed in the main body portion 121, and the first groove G1 and the second groove G2 communicate with each other.

In the step (3), the main body portion 121 is expanded by receiving the force applied by the insulating substrate 11. Since the protrusion 122 is regulated by the protective layer 15 and the protrusion 122 hardly extends, the region of the main body 121 near the protrusion 122 receives the reaction force of the protrusion 122. That is, since the region of the main body 121 near the protrusion 122 receives the acting force of the insulating substrate 11 and the protrusion 122 at the same time, the region of the main body 121 near the protrusion 122 is likely to come off from the insulating substrate 11. On the other hand, in the present application, since the second groove G2 extends to a region close to the protrusion 122 of the main body 121, the force applied to the main body 121 is effectively released, the stress concentration is reduced, and insulation is performed. The probability that the substrate 11 and the main body 121 slide relatively is effectively reduced, and the performance of the electrode member 1 is ensured.

The striped groove G includes a plurality of third grooves G3 formed in the main body portion 121 and arranged at intervals in the width direction X. In the width direction X, each third groove G3 is located between two adjacent second grooves G2, and in the height direction Z, the third groove G3 and the second groove G2 are displaced from each other. ..

22 to 24 are schematic views showing a fifth embodiment of the electrode member according to the present invention. With reference to FIGS. 22 to 24, the striped groove G of the fifth embodiment includes a third groove G3 and a fourth groove G4 formed in the main body portion 121. The third grooves G3 are plural and are arranged at intervals in the width direction X, and the fourth grooves G4 are plural and are arranged at intervals in the width direction X.

In the width direction X, each third groove G3 is located between two adjacent fourth grooves G4. In the height direction Z, the third groove G3 and the fourth groove G4 are displaced from each other. The third groove G3 and the fourth groove G4 are dispersedly arranged in the width direction X and the height direction Z, so that the effect of releasing stress can be improved and the uniformity can be improved.

The present application provides a method for manufacturing a secondary battery, which can further improve the safety performance of the secondary battery. As a method for manufacturing a secondary battery, a positive electrode member 2, a negative electrode member 3 and a diaphragm 4 are prepared, and the positive electrode member 2, the diaphragm 4 and the negative electrode member 3 are integrally wound to form an electrode assembly, and the positive electrode is formed. The electrode member 1 is used for at least one of the member 2 and the negative electrode member 3, an adapter piece 8 is prepared, and a plurality of conductive structures 16 of the electrode assembly are laminated on the adapter piece 8. Welding, preparing the top cover plate 6 and the electrode terminal 7 fixed to the top cover plate 6, welding the adapter piece 8 to the electrode terminal 7, preparing the case 5, and preparing the electrode. The assembly is arranged in the case 5 and the top cover plate 6 is connected to the case 5.

The electrode member 1 used in the manufactured secondary battery has a thin first conductive layer 12, and when a foreign substance breaks through the electrode member 1 of the secondary battery, the foreign substance breaks through the first conductive layer 12. Since the burr generated at the location is small and it is difficult to break through the diaphragm 4, a short circuit is avoided and the safety performance is improved. Further, a striped groove G is formed in the first conductive layer 12, and the striped groove G effectively releases the force applied to the first conductive layer 12 to reduce stress concentration. The risk of the first conductive layer 12 coming off the surface of the insulating substrate 11 can be effectively reduced, and the performance of the electrode member 1 and the secondary battery can be ensured.

In the following, drawing reference numerals will be described.
1 Electrode member, 5 Case, 11 Insulation substrate, 6 Top cover plate, 12 First conductive layer, 7 Electrode terminal, 121 Main body, 8 Adapter piece, 122 Protrusion, 9 Roller, 13 Active material layer, G stripe Groove, 14 second conductive layer, G1 first groove, 141 first part, G2 second groove, 142 second part, G3 third groove, 15 protective layer, G4 fourth groove, 16 Conductive structure, P electric guide part, 2 positive electrode member, X width direction, 3 negative electrode member, Y thickness direction, 4 diaphragm, Z height direction.

Claims (19)

The insulating substrate (11), the first conductive layer (12), and the active material layer (13) are included.
The first conductive layer (12) is provided on the surface of the insulating substrate (11), and the active material layer (13) is far from the insulating substrate (11) of the first conductive layer (12). It is provided on the side,
The first conductive layer (12) is provided with a striped groove (G) extending in the height direction (Z).
The electrode member (1) of the secondary battery, characterized in that. Further comprising a second conductive layer (14) having a first portion (141) located within the striped groove (G).
The electrode member (1) according to claim 1. The second conductive layer (14) is provided on a surface of the first conductive layer (12) away from the insulating substrate (11), and is connected to the first portion (141). A second portion (142) is further provided, and the active material layer (13) is provided on a surface of the second portion (142) away from the first conductive layer (12).
The electrode member (1) according to claim 2. The first conductive layer (12) is not coated with the main body portion (121) to which the active material layer (13) is applied and the active material layer (13) extending from the main body portion (121). Including the protrusion (122)
The striped groove (G) includes a first groove (G1) formed in the protrusion (122), and the second portion (142) is at least partially the protrusion (122). ), Which is located on a surface away from the insulating substrate (11).
The electrode member (1) according to claim 3. The striped groove (G) further includes a second groove (G2) formed in the main body portion (121), and the first groove (G1) and the second groove (G2) are formed. Communicating,
The electrode member (1) according to claim 4. A protective layer (15) provided on the surface of the second portion (142) away from the protrusion (122) and connected to the active material layer (13) is further included.
The first groove (G1) does not protrude from the protective layer (15).
The electrode member (1) according to claim 4. The rigidity of the second conductive layer (14) is smaller than the rigidity of the first conductive layer (12).
The electrode member (1) according to claim 2. The striped groove (G) penetrates the first conductive layer (12) along the thickness direction (Y), and the first portion (141) of the second conductive layer (14). Is connected to the insulating substrate (11),
The electrode member (1) according to claim 2. A plurality of the striped grooves (G) are provided, and the plurality of the striped grooves (G) are arranged at intervals in the width direction (X).
The electrode member (1) according to claim 1. The electrode assembly including the electrode member (1) according to any one of claims 1 to 9 is provided.
A secondary battery characterized by that. Preparing the insulating substrate (11) and
A first conductive layer (12) is formed by fixing the conductive material to the surface of the insulating substrate (11), and a stripe shape extending in the height direction (Z) on the first conductive layer (12). The groove (G) is provided and
A method for manufacturing a current collector, which comprises. The conductive material is fixed to the surface of the insulating substrate (11) by a vapor phase growth method or electroless plating.
The method for manufacturing a current collector according to claim 11. The conductive slurry is applied to a part of the surface of the first conductive layer (12), and the conductive slurry is filled in the striped groove.
Further comprising forming a second conductive layer (14) after curing of the conductive slurry.
The method for manufacturing a current collector according to claim 11 or 12, wherein the current collector is manufactured. To prepare a current collector manufactured by the manufacturing method according to claim 11 or 12.
A slurry containing an active material is applied to a part of the surface of the first conductive layer (12), and the slurry containing the active material is filled in the striped groove (G).
After the slurry containing the active material is cured, the active material layer (13) is formed, and the active material layer (13) is roll-pressed.
Welding the metal foil material to the region of the first conductive layer where the active material layer (13) is not applied, and
A part of the metal foil material and a part of the current collector are removed to form a plurality of spaced conductive structures (16) and a plurality of spaced electric guide portions (P). That and
A method for manufacturing an electrode member. A slurry containing an insulating material is applied to a part of the surface of the first conductive layer (12) to form a protective layer (15) after the slurry containing the insulating material is cured.
The protective layer (15) comprises forming the metal foil material before welding.
The method for manufacturing an electrode member according to claim 14, wherein the electrode member is manufactured. A positive electrode member (2), a negative electrode member (3), and a diaphragm (4) are prepared, and the positive electrode member (2), the diaphragm (4), and the negative electrode member (3) are integrally wound to form an electrode assembly. At least one of the positive electrode member (2) and the negative electrode member (3) is manufactured by the method for manufacturing an electrode member according to claim 14 or 15.
The adapter piece (8) is prepared, and the plurality of conductive structures (16) of the electrode assembly are laminated and welded to the adapter piece (8).
The top cover plate (6) and the electrode terminal (7) fixed to the top cover plate (6) are prepared, and the adapter piece (8) is welded to the electrode terminal (7).
The case (5) is prepared, the electrode assembly is arranged in the case (5), and the top cover plate (6) is connected to the case (5).
A method for manufacturing a secondary battery, which comprises. To prepare a current collector manufactured by the manufacturing method according to claim 13,
Applying the slurry containing the active material to a part of the surface of the second conductive layer (14), and
After the slurry containing the active material is cured, the active material layer (13) is formed and the active material layer (13) is roll-pressed.
Welding the metal foil material to the region of the first conductive layer (12) where the second conductive layer (14) is not applied, and
A part of the metal foil material and a part of the current collector are removed to form a plurality of spaced conductive structures (16) and a plurality of spaced electric guide portions (P). That and
A method for manufacturing an electrode member. After applying the slurry containing the insulating material to a part of the surface of the second conductive layer (14), the slurry containing the insulating material is cured to form the protective layer (15).
The protective layer (15) further comprises forming the metal foil material before welding.
The method for manufacturing an electrode member according to claim 17, wherein the electrode member is manufactured. A positive electrode member (2), a negative electrode member (3), and a diaphragm (4) are prepared, and the positive electrode member (2), the diaphragm (4), and the negative electrode member (3) are integrally wound to form an electrode assembly. A solid is formed, and at least one of the positive electrode member (2) and the negative electrode member (3) is manufactured by the method for manufacturing an electrode member according to claim 17 or 18.
The adapter piece (8) is prepared, and the plurality of conductive structures (16) of the electrode assembly are laminated and welded to the adapter piece (8).
The top cover plate (6) and the electrode terminal (7) fixed to the top cover plate (6) are prepared, and the adapter piece (8) is welded to the electrode terminal (7).
The case (5) is prepared, the electrode assembly is placed in the case (5), and the cover plate (6) is connected to the case (5).
A method for manufacturing a secondary battery, which comprises.

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