Battery cell, battery, battery pack and electric device

Abstract

The embodiments of the present application relate to the technical field of battery cells. Provided are a battery cell, a battery, a battery pack and an electric device. The battery cell comprises a first encapsulation film layer, a second encapsulation film layer and an electrode core. At least one of the first encapsulation film layer and the second encapsulation film layer comprises a metal layer and a bonding layer. The metal layer comprises a first region and a second region, and the bonding layer covers the second region, but does not cover the first region, or the thickness of the bonding layer covering the first region is less than the thickness of the bonding layer covering the second region. At least part of the bonding layer located in the second region is used for edge sealing, such that the first encapsulation film layer and the second encapsulation film layer enclose a sealed cavity, and the electrode core is disposed inside the sealed cavity. In this way, the battery cell can have a relatively high volumetric energy density.

Description

Battery cell, battery, battery pack and electric device

[0001] The present application claims priority to the Chinese Patent Application No. 202422334935.5, filed on September 24, 2024, entitled "Battery cell, battery, battery pack and electric device", and to the Chinese Patent Application No. 202520213962.9, filed on February 8, 2025, entitled "Battery cell, battery, battery pack and electric device", the contents of which are incorporated herein by reference in their entirety. TECHNICAL FIELD

[0002] Embodiments of the present application relate to the technical field of battery cells, and in particular to a battery cell, a battery, a battery pack and an electric device. BACKGROUND

[0003] A battery cell is a power storage component of a battery or a battery pack, and is widely used in devices such as mobile phones, tablet computers, vehicles, unmanned aerial vehicles, robots, and power storage base stations.

[0004] In the related art, a battery cell has a packaging structure and a pole core disposed in the packaging structure. The packaging structure can be formed by edge bonding of two layers of packaging films. In the related art, the volumetric energy density of the battery cell needs to be improved. SUMMARY

[0005] Embodiments of the present application provide a battery cell, a battery, a battery pack and an electric device, which can make the battery cell have a higher volumetric energy density.

[0006] A first aspect of embodiments of the present application provides a battery cell. The battery cell includes a first packaging film layer, a second packaging film layer and a pole core. At least one of the first packaging film layer and the second packaging film layer includes a metal layer and a bonding layer. The metal layer includes a first region and a second region, and the bonding layer covers the second region and does not cover the first region, or the thickness of the bonding layer covering the first region is less than the thickness of the bonding layer covering the second region. At least part of the bonding layer located in the second region is used for edge sealing, so that the first packaging film layer and the second packaging film layer form a sealed cavity, and the pole core is disposed in the sealed cavity. Here, the metal layer refers to the metal layer including the first region and the second region.

[0007] The battery cell provided by the embodiments of the present application can achieve edge sealing by using the bonding layer, and by thinning or removing the bonding layer of the first region, a capacity expansion space can be formed at the first region. On the basis of the unchanged size of the battery cell, the capacity expansion space increases the capacity of the sealed cavity, which is beneficial to increase the arrangement amount of the electrode material in the sealed cavity, and further beneficial to improve the volumetric energy density of the battery cell.

[0008] In a possible implementation, the first region is located on a large face of the battery cell. The large face of the battery cell refers to a face with the largest area on the packaging structure of the battery cell.

[0009] In this way, the recess for forming the packaging structure can be formed by stamping the first packaging film layer and the second packaging film layer, the bottom wall of the recess is used to form the large face of the battery cell, the first region is located on the bottom wall of the recess, and the original bonding layer on the bottom wall of the recess is easier to process (for example, laser cleaning), so that the expansion space is easier to form.

[0010] In a possible implementation, the second region includes a first sub-region and a second sub-region, the bonding layer located on the first sub-region is used for edge sealing, the bonding layer located on the second sub-region is not used for edge sealing, and the second sub-region is located between the first region and the first sub-region.

[0011] In this way, the second sub-region not used for edge sealing is provided with the bonding layer, and the bonding layer located on the second sub-region can play a role in insulation protection in the second sub-region. In addition, the bonding layer located on the second sub-region can also improve the strength of the second sub-region, so that the second sub-region is not easy to be damaged due to stretching and the like.

[0012] In a possible implementation, when the thickness of the bonding layer covering the first region is less than the thickness of the bonding layer covering the second region, the thickness of the bonding layer covering the first region is less than the thickness of the bonding layer covering the second sub-region.

[0013] In this way, the bonding layer covering the second sub-region with a relatively large thickness can play a better role in improving the strength and insulation protection in the second sub-region. In addition, the bonding layer located on the first region with a relatively small thickness can also play a role in improving the strength and insulation protection.

[0014] In a possible implementation, part of the second region is located on the large face of the battery cell.

[0015] In this way, the accuracy requirement for the position of the edge of the formed expansion space is relatively low, so that the expansion space is easier to form. In addition, the second region extends to the large face of the battery cell, the bonding layer covers the corner between the large face of the battery cell and the edge sealing position, the corner between the large face of the battery cell and the edge sealing position has good strength and is not easy to be damaged due to stretching and the like. In addition, the corner between the large face of the battery cell and the edge sealing position has good insulation performance.

[0016] In a possible implementation, the second region is located outside the first region, and the bonding layer located on the second region is used for edge sealing. In this way, a larger expansion space can be formed.

[0017] In a possible implementation, when the bonding layer covers the second region and does not cover the first region: the thickness of the metal layer located at the first region is less than the thickness of the metal layer located at the second region.

[0018] In this way, the electrode material can be arranged by using the part of the metal layer that is emptied at the first region, which facilitates further increasing the arrangement amount of the electrode material inside the packaging structure.

[0019] In a possible implementation, when the bonding layer covers the second region and does not cover the first region: the surface of the first region close to the core is covered with an oxidation layer.

[0020] In this way, the oxidation layer formed can improve the strength of the packaging structure at the first region, so that the packaging structure is less likely to be damaged.

[0021] In a possible implementation, the battery cell further includes a first electrode sheet. The first electrode sheet is arranged in the sealed cavity, and the first electrode sheet is arranged between the core and the first region.

[0022] In this way, the arrangement amount of the electrode material inside the packaging structure can be increased by adding the first electrode sheet between the core and the first region, and thus the volumetric energy density of the battery cell can be improved, and it is relatively easy to increase the arrangement amount of the electrode material inside the packaging structure.

[0023] In a possible implementation, the first electrode sheet includes a first current collector and a first electrode material, and the first electrode material is arranged on the side of the first current collector close to the core.

[0024] In this way, the utilization rate of the electrode material coated on the first electrode sheet is high, and the coating amount of the electrode material that can be utilized on the first electrode sheet is facilitated to be increased.

[0025] In a possible implementation, when the bonding layer covers the second region and does not cover the first region: the surface of the first region close to the core is provided with a second electrode material.

[0026] In this way, the arrangement amount of the electrode material of the packaging structure can be increased by arranging the electrode material on the surface of the first region, and thus the volumetric energy density of the battery cell can be improved. In addition, the metal layer including the first region and the second region is utilized as a current collector that carries the electrode material, the space utilization rate of the battery cell is high, and the amount of the electrode material that can be arranged in the expansion space is large, which facilitates the improvement of the volumetric energy density of the battery cell.

[0027] In a possible implementation, the battery cell further includes a tab, and the metal layer includes a connecting portion protruding from the outer edge of the second region, the connecting portion is located outside the sealed cavity, and the connecting portion is connected with the tab.

[0028] In this way, the metal layer can be connected with the tab outside the packaging structure through the connecting portion, so that the metal layer including the first region and the second region is easier to be connected with the tab. In addition, the connection between the metal layer and the tab is less likely to damage the packaging structure.

[0029] In a possible implementation, the metal layer is an aluminum layer, and the second electrode material is a cathode electrode material.

[0030] In this way, the second electrode material arranged on the surface of the metal layer as the aluminum layer is facilitated to generate the galvanic cell reaction and the electrolysis reaction, so as to improve the volume energy density of the battery cell with the metal layer as the aluminum layer.

[0031] In a possible implementation, the metal layer is a steel layer, and the second electrode material is an anode electrode material.

[0032] In this way, the second electrode material arranged on the surface of the metal layer as the steel layer is facilitated to generate the galvanic cell reaction and the electrolysis reaction, so as to improve the volume energy density of the battery cell with the metal layer as the steel layer.

[0033] The second aspect of the embodiments of the present application provides a battery, which includes the battery cell in any of the above-mentioned embodiments.

[0034] The third aspect of the embodiments of the present application provides a battery pack, which includes a battery management system and the battery cell in any of the above-mentioned embodiments, and the battery cell is electrically connected with the battery management system.

[0035] The fourth aspect of the embodiments of the present application provides a power consumption device, which includes the battery in any of the above-mentioned embodiments or the battery pack in any of the above-mentioned embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0036] FIG. 1 is a schematic diagram of a battery cell according to an embodiment of the present application;

[0037] FIG. 2 is a schematic diagram of a cross section of a battery cell according to an embodiment of the present application;

[0038] FIG. 3 is a schematic diagram of a layer stack of a first packaging film layer according to an embodiment of the present application;

[0039] FIG. 4 is a schematic diagram of a first packaging film layer and a second packaging film layer according to an embodiment of the present application;

[0040] FIG. 5 is a schematic diagram of a cross section of a pole core of a battery cell at a first region according to an embodiment of the present application;

[0041] FIG. 6 is a schematic diagram of a cross section of a pole core of a battery cell at a first electrode sheet according to an embodiment of the present application;

[0042] FIG. 7 is a schematic diagram of a cross section of another battery cell according to an embodiment of the present application;

[0043] FIG. 8 is a schematic view of a stack of a first encapsulation film layer provided with a second electrode material according to an embodiment of the present application;

[0044] FIG. 9 is a schematic view of a cross section of another battery cell according to an embodiment of the present application;

[0045] FIG. 10 is a schematic view of a cross section of a jelly-roll of a battery cell according to an embodiment of the present application;

[0046] FIG. 11 is a schematic view of another first encapsulation film layer and second encapsulation film layer according to an embodiment of the present application;

[0047] FIG. 12 is a schematic view of another battery cell according to an embodiment of the present application;

[0048] FIG. 13 is a schematic view of a stack of a second encapsulation film layer according to an embodiment of the present application;

[0049] FIG. 14 is a schematic view of another first encapsulation film layer and second encapsulation film layer according to an embodiment of the present application;

[0050] FIG. 15 is a schematic view of a cross section of another battery cell according to an embodiment of the present application;

[0051] FIG. 16 is a schematic view of a cross section of another battery cell according to an embodiment of the present application;

[0052] FIG. 17 is a schematic view of a stack of a second encapsulation film layer provided with a second electrode material according to an embodiment of the present application;

[0053] FIG. 18 is a schematic view of a cross section of another battery cell according to an embodiment of the present application;

[0054] FIG. 19 is a schematic view of another first encapsulation film layer and second encapsulation film layer according to an embodiment of the present application;

[0055] FIG. 20 is a schematic view of a cross section of another battery cell according to an embodiment of the present application;

[0056] FIG. 21 is a schematic view of a cross section of another battery cell according to an embodiment of the present application;

[0057] FIG. 22 is a schematic view of a cross section of another battery cell according to an embodiment of the present application;

[0058] FIG. 23 is a schematic view of a cross section of another battery cell according to an embodiment of the present application;

[0059] FIG. 24 is a schematic view of a cross section of another battery cell according to an embodiment of the present application;

[0060] FIG. 25 is a schematic view of a cross section of another battery cell according to an embodiment of the present application;

[0061] FIG. 26 is a schematic cross-sectional view of another type of battery cell, according to embodiments of the present application;

[0062] FIG. 27 is a schematic cross-sectional view of another type of battery cell, according to embodiments of the present application.

[0063] Legend: 10, package structure; 11, sealed cavity; 12, first encapsulation film layer; 13, second encapsulation film layer; 20, first tab; 21, first bonding material; 30, second tab; 31, second bonding material; 40, connecting section; 50, insulating material; 110, metal layer; 110a, first metal layer; 110b, second metal layer; 111, connecting portion; 120, bonding layer; 120a, first bonding layer; 120b, second bonding layer; 130, adhesive layer; 130a, first adhesive layer; 130b, second adhesive layer; 130c, third adhesive layer; 130d, fourth adhesive layer; 140a, first protective layer; 140b, second protective layer; 150, oxidation layer; 150a, first oxidation layer; 200, battery cell; 210, second electrode sheet; 211, second current collector; 212, third electrode material; 220, first separator film; 230, third electrode sheet; 231, third current collector; 232, fourth electrode material; 300, first electrode sheet; 310, first current collector; 320, first electrode material; 400, second electrode material; S1, first region; S2, second region; S21, first sub-region; S22, second sub-region. DETAILED DESCRIPTION

[0064] The terms used in the embodiments section of the present application are only used to explain the specific embodiments of the present application, and are not intended to limit the present application, which will be described in detail below with reference to the accompanying drawings.

[0065] The embodiments of the present application provide a power consuming device, which can include but is not limited to a mobile phone, a tablet computer, a notebook computer, an e-reader, a wearable device, a vehicle, a drone, a robot, a power storage base station, a mobile power supply, and the like, which has a power storage capability. The power consuming device includes a battery or a battery pack.

[0066] In some possible embodiments, the power consuming device includes a battery, and the battery includes a battery cell, which is used for power storage.

[0067] For example, the battery protection plate can implement overcharge protection, overdischarge protection, overcurrent protection, short circuit protection, overtemperature protection, and balance protection functions for the battery cell.

[0068] In some possible embodiments, the power-consuming device includes a battery pack, the battery pack can include a battery management system (BMS) and a plurality of battery cells, the plurality of battery cells can be connected in series or in parallel, the battery cells are electrically connected with the battery management system, the battery cells are used for storing electricity, and the battery management system can manage all the electrically connected battery cells.

[0069] For example, the battery pack can include a plurality of batteries, the plurality of batteries can be connected in series or in parallel, and the battery cells of the batteries can be electrically connected with the battery management system through a battery protection board.

[0070] In some examples, the power-consuming device can further include a load, the battery cells are electrically connected with the load, and the battery cells can supply power to the load.

[0071] When the power-consuming device includes the battery protection board, the battery cells can be electrically connected with the load through the battery protection board.

[0072] When the power-consuming device includes the battery management system, the battery cells can be electrically connected with the load through the battery management system.

[0073] For example, the load can include, but is not limited to, a processor, a display screen, and the like.

[0074] In some examples, the power-consuming device can further include a power conversion device, the battery cells are electrically connected with the power conversion device, and the power conversion device can be used to convert an electric current from an external source into an electric current required by the battery cells and then deliver the electric current to the battery cells.

[0075] When the power-consuming device includes the battery protection board, the battery cells can be electrically connected with the power conversion device through the battery protection board.

[0076] When the power-consuming device includes the battery management system, the battery cells can be electrically connected with the power conversion device through the battery management system.

[0077] FIG. 1 is a schematic diagram of a battery cell according to an embodiment of the present application.

[0078] As shown in FIG. 1, in the embodiment of the present application, the battery cell includes a packaging structure 10 and a pole core 200, the pole core 200 can also be called a bare battery cell, the packaging structure 10 encloses to form a sealed cavity 11, and the pole core 200 is arranged in the sealed cavity 11, that is, the pole core 200 is arranged in the packaging structure 10.

[0079] In some examples, the pole core 200 can be a winding structure, that is, the pole core 200 can be a winding pole core.

[0080] In other examples, the pole core 200 can be a laminated structure, that is, the pole core 200 can be a laminated pole core.

[0081] In the embodiments of the present application, the battery cell further comprises a plurality of tabs, parts of the tabs are located in the sealed cavity 11 and electrically connected with the electrode core 200, parts of the tabs are led out of the packaging structure 10 and electrically connected with the devices outside the packaging structure 10, so that the electrode core 200 is electrically connected with the devices outside the packaging structure 10 through the tabs.

[0082] For example, one of the plurality of tabs is a first tab 20, and another of the plurality of tabs is a second tab 30, parts of the first tab 20 and the second tab 30 are located in the sealed cavity 11 and electrically connected with the electrode core 200, parts of the first tab 20 and the second tab 30 are led out of the packaging structure 10 and electrically connected with the devices outside the packaging structure 10, so that the electrode core 200 is electrically connected with the devices outside the packaging structure 10 through the first tab 20 and the second tab 30.

[0083] In the example that the battery cell is electrically connected with a load, the first tab 20 and the second tab 30 are electrically connected with the load located outside the packaging structure 10. For example, the first tab 20 and the second tab 30 can be electrically connected with a battery protection plate located outside the packaging structure 10, and the first tab 20 and the second tab 30 are electrically connected with the load through the battery protection plate. For another example, the first tab 20 and the second tab 30 can be electrically connected with a battery management system located outside the packaging structure 10, and the first tab 20 and the second tab 30 are electrically connected with the load through the battery management system.

[0084] In the example that the battery cell is electrically connected with a power conversion device, the first tab 20 and the second tab 30 are electrically connected with the power conversion device located outside the packaging structure 10. For example, the first tab 20 and the second tab 30 can be electrically connected with a battery protection plate located outside the packaging structure 10, and the first tab 20 and the second tab 30 are electrically connected with the power conversion device through the battery protection plate. For another example, the first tab 20 and the second tab 30 can be electrically connected with a battery management system located outside the packaging structure 10, and the first tab 20 and the second tab 30 are electrically connected with the power conversion device through the battery management system.

[0085] For example, the electrode core 200 comprises a plurality of electrode sheets and a plurality of isolation films, parts of the plurality of electrode sheets are cathode electrode sheets, and parts of the plurality of electrode sheets are anode electrode sheets, that is, the electrode core 200 comprises the cathode electrode sheets, the anode electrode sheets and the isolation films, the cathode electrode sheets and the anode electrode sheets are arranged alternately, the isolation films are arranged between adjacent cathode electrode sheets and anode electrode sheets, and the adjacent cathode electrode sheets and anode electrode sheets are separated by the isolation films therebetween. The cathode electrode sheets are electrically connected with one of the first tab 20 and the second tab 30, and the anode electrode sheets are electrically connected with the other of the first tab 20 and the second tab 30.

[0086] The cathode electrode sheet includes a cathode current collector and a cathode electrode material, the cathode electrode material is arranged on the surface of the cathode current collector, and the cathode current collector is electrically connected with one of the first tab 20 and the second tab 30. The anode electrode sheet includes an anode current collector and an anode electrode material, the anode electrode material is arranged on the surface of the anode current collector, and the anode current collector is electrically connected with the other of the first tab 20 and the second tab 30.

[0087] The cathode electrode sheet and the anode electrode sheet are electrode sheets with opposite polarities, the cathode current collector and the anode current collector are current collectors with opposite polarities, and the cathode electrode material and the anode electrode material are electrode materials with opposite polarities.

[0088] For example, the cathode electrode material can include, but is not limited to, lithium cobalt oxide, lithium iron phosphate, etc.

[0089] For example, the cathode current collector can be made of aluminum.

[0090] For example, the anode electrode material can include, but is not limited to, graphite, silicon-based material, etc.

[0091] For example, the anode current collector can be made of copper.

[0092] FIG. 2 is a cross-sectional view of an electric core according to an embodiment of the present application.

[0093] As shown in FIG. 2, and referring to FIG. 1, the packaging structure 10 includes a first packaging film layer 12 and a second packaging film layer 13. At least one of the first packaging film layer 12 and the second packaging film layer 13 includes a metal layer 110 and a bonding layer 120, and the first packaging film layer 12 and the second packaging film layer 13 are bonded to form the packaging structure 10 through the bonding layer 120 to form a sealed cavity 11.

[0094] For example, the first packaging film layer 12 includes the metal layer 110 and the bonding layer 120, the metal layer 110 of the first packaging film layer 12 is a first metal layer 110a, the bonding layer 120 of the first packaging film layer 12 is a first bonding layer 120a, and the first bonding layer 120a is arranged on one side of the first metal layer 110a in the thickness direction. That is, the first metal layer 110a includes a first surface, the first surface is located on one side of the first metal layer 110a in the thickness direction, and the first bonding layer 120a is stacked on the first surface. The first surface refers to the surface located on one side of the first metal layer 110a in the thickness direction, and the first surface can be a continuous surface, or the first surface can include multiple surfaces with discontinuities.

[0095] The first metal layer 110a can make the first packaging film layer 12 have better structural strength and better sealing performance.

[0096] Exemplarily, the second encapsulation film layer 13 comprises a metal layer 110 and a bonding layer 120, the metal layer 110 of the second encapsulation film layer 13 is a second metal layer 110b, the bonding layer 120 of the second encapsulation film layer 13 is a second bonding layer 120b, and the second bonding layer 120b is arranged on one side of the second metal layer 110b in the thickness direction. That is, the second metal layer 110b comprises a second surface, the second surface is located on one side of the second metal layer 110b in the thickness direction, and the second bonding layer 120b is stacked on the second surface. The second surface refers to the surface located on one side of the second metal layer 110b in the thickness direction. The second surface can be a continuous surface, or the second surface can comprise a plurality of surfaces with discontinuities.

[0097] The second metal layer 110b can make the second encapsulation film layer 13 have better structural strength and better sealing performance.

[0098] The first surface and the second surface are arranged opposite to each other. That is, the first bonding layer 120a and the second bonding layer 120b are arranged opposite to each other. At least part of the first bonding layer 120a and at least part of the second bonding layer 120b are combined into one body, so that the first encapsulation film layer 12 and the second encapsulation film layer 13 form an encapsulation structure 10 to enclose a sealed cavity 11. The first tab 20 and the second tab 30 are arranged between the first encapsulation film layer 12 and the second encapsulation film layer 13. Part of the first tab 20 is located outside the encapsulation structure 10, part of the first tab 20 is located inside the sealed cavity 11, and part of the first tab 20 is wrapped by the first encapsulation film layer 12 and the second encapsulation film layer 13. Part of the second tab 30 is located outside the encapsulation structure 10, part of the second tab 30 is located inside the sealed cavity 11, and part of the second tab 30 is wrapped by the first encapsulation film layer 12 and the second encapsulation film layer 13.

[0099] After at least part of the first bonding layer 120a and at least part of the second bonding layer 120b are combined, the combined part of the first bonding layer 120a and the second bonding layer 120b forms an integrated structure.

[0100] Exemplarily, at least part of the first bonding layer 120a and at least part of the second bonding layer 120b can be combined by hot pressing. After hot pressing, the combined part of the first bonding layer 120a and the second bonding layer 120b can be fused into one body.

[0101] Exemplarily, the first tab 20 is combined with the first bonding layer 120a and the second bonding layer 120b. For example, the outer peripheral surface of the part of the first tab 20 wrapped by the first encapsulation film layer 12 and the second encapsulation film layer 13 is coated with a first bonding material 21. The first tab 20 is combined with the first bonding layer 120a and the second bonding layer 120b through the first bonding material 21, so that the first tab 20 is easily combined and fixed with the encapsulation structure 10, and the combination and fixation are relatively stable.

[0102] The first bonding material 21 is a material similar in properties to the first bonding layer 120a and the second bonding layer 120b, so as to facilitate bonding with the first bonding layer 120a and the second bonding layer 120b.

[0103] For example, the first bonding material 21 is integrated with the first bonding layer 120a and the second bonding layer 120b, that is, after the first bonding material 21 is bonded with the first bonding layer 120a and the second bonding layer 120b, the first bonding material 21 and the first bonding layer 120a and the second bonding layer 120b form an integrated structure.

[0104] For example, the second tab 30 is bonded with the first bonding layer 120a and the second bonding layer 120b. For example, the outer circumferential surface of the part of the second tab 30 wrapped by the first packaging film layer 12 and the second packaging film layer 13 is coated with the second bonding material 31, and the second tab 30 is bonded with the first bonding layer 120a and the second bonding layer 120b through the second bonding material 31, so that the second tab 30 is easily bonded and fixed with the packaging structure 10, and the bonding and fixing is relatively stable.

[0105] The second bonding material 31 is a material similar in properties to the first bonding layer 120a and the second bonding layer 120b, so as to facilitate bonding with the first bonding layer 120a and the second bonding layer 120b.

[0106] For example, the second bonding material 31 is integrated with the first bonding layer 120a and the second bonding layer 120b, that is, after the second bonding material 31 is bonded with the first bonding layer 120a and the second bonding layer 120b, the second bonding material 31 and the first bonding layer 120a and the second bonding layer 120b form an integrated structure.

[0107] For example, the material forming the first bonding layer 120a and the second bonding layer 120b can include but is not limited to polyolefin, acid-modified polyolefin, and mixtures thereof.

[0108] For example, the first bonding layer 120a and the second bonding layer 120b are formed by the same material, so that the first bonding layer 120a and the second bonding layer 120b are easily bonded and relatively stable after bonding. For example, the first bonding layer 120a and the second bonding layer 120b can be polypropylene (PP) layers, and the first bonding layer 120a and the second bonding layer 120b can be bonded by hot pressing.

[0109] In some examples, the first packaging film layer 12 can be an aluminum plastic film layer, and at this time, the first metal layer 110a is an aluminum layer.

[0110] In other examples, the first packaging film layer 12 can be a steel plastic film layer, and at this time, the first metal layer 110a is a steel layer.

[0111] In some examples, the second packaging film layer 13 can be an aluminum-plastic film layer, and the second metal layer 110b can be an aluminum layer.

[0112] In some other examples, the second packaging film layer 13 can be a steel-plastic film layer, and the second metal layer 110b can be a steel layer.

[0113] For example, the first packaging film layer 12 and the second packaging film layer 13 can be an integrated structure or a split structure.

[0114] When the first packaging film layer 12 and the second packaging film layer 13 are an integrated structure, the first packaging film layer 12 and the second packaging film layer 13 are two parts formed by folding the same piece of packaging film, the first metal layer 110a and the second metal layer 110b are an integrated structure, and the first bonding layer 120a and the second bonding layer 120b are an integrated structure.

[0115] When the first packaging film layer 12 and the second packaging film layer 13 are an integrated structure, the first metal layer 110a and the second metal layer 110b are made of the same material, and the first bonding layer 120a and the second bonding layer 120b are made of the same material.

[0116] In some examples, the first packaging film layer 12 and the second packaging film layer 13 can both be aluminum-plastic film layers or both be steel-plastic film layers. In this case, the first packaging film layer 12 and the second packaging film layer 13 can be an integrated structure or a split structure.

[0117] In some other examples, one of the first packaging film layer 12 and the second packaging film layer 13 can be an aluminum-plastic film layer, and the other of the first packaging film layer 12 and the second packaging film layer 13 can be a steel-plastic film layer. In this case, the first packaging film layer 12 and the second packaging film layer 13 are a split structure.

[0118] In related technologies, the inner surface of the first packaging film layer is covered by the first bonding layer with uniform thickness, and the inner surface of the second packaging film layer is covered by the second bonding layer with uniform thickness, that is, the first surface of the first metal layer is covered by the first bonding layer with uniform thickness, and the second surface of the second metal layer is covered by the second bonding layer with uniform thickness. In this case, the first bonding layer includes a first edge portion and a first side wall portion, the first edge portion is arranged outside the first side wall portion, the second bonding layer includes a second edge portion and a second side wall portion, the second edge portion is arranged outside the second side wall portion, the first edge portion is opposite to the second edge portion, and the first edge portion and the second edge portion are used for edge sealing, that is, the first edge portion and the second edge portion are combined to form an encapsulation structure of the first packaging film layer and the second packaging film layer. The first side wall portion and the second side wall portion are used to form the inner wall of the encapsulation cavity.

[0119] In the related art, the first side wall part and the second side wall part not used for edge sealing have a relatively thick thickness, which occupies the space of the battery cell, so that the internal space of the packaging structure is relatively small, and thus the electrode material that can be arranged in the packaging structure is relatively small, and the volumetric energy density of the battery cell is relatively low.

[0120] FIG. 3 is a schematic diagram of a layer stack of a first packaging film layer according to an embodiment of the present application, and FIG. 4 is a schematic diagram of the first packaging film layer and a second packaging film layer according to an embodiment of the present application.

[0121] As shown in FIGS. 3 and 4, and referring to FIG. 2, based on this, in the present embodiment, at least one of the first metal layer 110a and the second metal layer 110b includes a first region S1 and a second region S2, and the bonding layer 120 covers the second region S2, at least part of the bonding layer 120 located at the second region S2 is used for edge sealing, so that the first packaging film layer 12 and the second packaging film layer 13 form the packaging structure 10 to enclose the sealed cavity 11.

[0122] In some possible implementations, the bonding layer 120 does not cover the first region S1, so as to form an expansion space at the first region S1. The expansion space is a space in the packaging structure 10, that is, the expansion space is part of the space in the sealed cavity 11.

[0123] In this way, while the bonding layer 120 can be used for edge sealing, by not covering the first region S1, the bonding layer 120 can leave space at the first region S1 to form an expansion space, which increases the capacity of the sealed cavity 11 on the basis of the unchanged size of the battery cell, and is beneficial to increase the arrangement amount of the electrode material in the sealed cavity 11, and thus is beneficial to increase the volumetric energy density of the battery cell.

[0124] In some examples, the first metal layer 110a includes the first region S1 and the second region S2, and the first bonding layer 120a covers the second region S2 of the first metal layer 110a and does not cover the first region S1 of the first metal layer 110a, so as to form an expansion space at the first region S1 of the first metal layer 110a. At least part of the first bonding layer 120a located at the second region S2 is used for edge sealing, that is, the first bonding layer 120a located at the second region S2 is combined with the second packaging film layer 13. For example, at least part of the first bonding layer 120a located at the second region S2 is combined with the second bonding layer 120b as a whole.

[0125] In this way, while the edge sealing can be achieved by the first bonding layer 120a, by making the first bonding layer 120a not cover the first region S1 of the first metal layer 110a, a space can be left out at the first region S1 of the first metal layer 110a to form an expanded space, and the capacity of the sealed cavity 11 can be increased on the basis of the unchanged size of the battery cell, which is conducive to increasing the amount of electrode material arranged in the sealed cavity 11, and further conducive to improving the volumetric energy density of the battery cell.

[0126] For example, the first surface includes a first edge sealing region and a first sidewall region, the first surface at the first region S1 is the first sidewall region, and at least part of the first surface at the second region S2 is the first edge sealing region. The first bonding layer 120a provided at the first edge sealing region is used for edge sealing, that is, the first bonding layer 120a provided at the first edge sealing region is combined with the second bonding layer 120b.

[0127] For example, the second region S2 is arranged around the outer edge of the first region S1, that is, the first edge sealing region is arranged around the outer edge of the first sidewall region.

[0128] For example, the inner edge of the second region S2 coincides with the outer edge of the first region S1.

[0129] In some examples, the bonding layer 120 at the second region S2 is used for edge sealing. That is, the first region S1 extends to the position where the bonding layer 120 is used for edge sealing. In this way, a larger expanded space can be formed.

[0130] In some examples, the first bonding layer 120a at the second region S2 is used for edge sealing, that is, the first region S1 of the first metal layer 110a extends to the position where the first bonding layer 120a is used for edge sealing. At this time, the first surface at the second region S2 is the first edge sealing region, the first bonding layer 120a is arranged at the first edge sealing region, and the orthographic projection of the first bonding layer 120a on the first surface is located outside the first sidewall region, that is, the first bonding layer 120a covers the first edge sealing region and does not cover the first sidewall region.

[0131] In this way, the first bonding layer 120a is arranged at the first sealing edge region, and the surface of the first side wall region is not provided with the first bonding layer 120a. In the thickness direction of the first packaging film layer 12, the first bonding layer 120a leaves a space opposite the first side wall region, thereby increasing the space inside the packaging structure 10. The space left at the position opposite the first side wall region can be used to arrange electrode materials, which is conducive to increasing the arrangement amount of electrode materials inside the packaging structure 10, and in turn conducive to improving the volumetric energy density of the battery cell. For example, the first bonding layer 120a originally covering the first region S1 of the first metal layer 110a can be removed by laser cleaning the inner surface of the first packaging film layer 12 to form an expanded space at the first region S1 of the first metal layer 110a.

[0132] For example, the first sealing edge region can be covered by the first bonding layer 120a.

[0133] For example, the second region S2 can surround the outer edge of the first region S1, or the second region S2 can surround part of the outer edge of the first region S1. That is, when the first metal layer 110a includes the first region S1 and the second region S2, the first sealing edge region can surround the outer edge of the first side wall region, or the first sealing edge region can only surround part of the outer edge of the first side wall region. As long as the first bonding layer 120a arranged at the first sealing edge region can combine with the second bonding layer 120b to form a sealed cavity 11 inside the packaging structure 10, the first sealing edge region can be arranged in this way. For example, when the first packaging film layer 12 and the second packaging film layer 13 are in an integrated structure, the outer edge of the first side wall region includes a first side edge integrally connected with the second packaging film layer 13, and the first sealing edge region surrounds part of the outer edge of the first side wall region excluding the first side edge.

[0134] For example, the distance between the outer edge of the first bonding layer 120a and the inner edge of the first bonding layer 120a is greater than or equal to 1 mm and less than or equal to 8 mm, that is, the width of the first bonding layer 120a is greater than or equal to 1 mm and less than or equal to 8 mm.

[0135] In this way, the first packaging film layer 12 and the second packaging film layer 13 can be combined more stably. In addition, the inner edge of the first bonding layer 120a can surround a larger space, so that the space inside the packaging structure 10 is larger, which is conducive to arranging more electrode materials.

[0136] For example, the first sealing edge region is located at the outer edge of the first surface, that is, the first bonding layer 120a is arranged at the outer edge of the first surface.

[0137] In some possible embodiments, the first bonding layer 120a is fixedly bonded to the first metal layer 110a by the adhesive layer 130, and specifically, the first bonding layer 120a is fixedly bonded to the first surface by the adhesive layer 130. The adhesive layer 130 that fixedly bonds the first bonding layer 120a to the first metal layer 110a is the first adhesive layer 130a.

[0138] In this way, the first bonding layer 120a is arranged on the first surface, and the first bonding layer 120a is fixedly and stably arranged on the first surface.

[0139] In some examples in which the first bonding layer 120a covers the second region S2 of the first metal layer 110a and does not cover the first region S1 of the first metal layer 110a, the first adhesive layer 130a covers the second region S2 of the first metal layer 110a and does not cover the first region S1 of the first metal layer 110a.

[0140] In this way, the electrode material can be arranged in the space left by the first adhesive layer 130a at the first region S1, and the arrangement amount of the electrode material inside the packaging structure 10 can be increased. In addition, the first region S1 of the first metal layer 110a is exposed to the inner surface of the first packaging film layer 12, and the electrode material can be arranged on the surface of the first region S1 of the first metal layer 110a, so that the first metal layer 110a can be used as a current collector to supply power to the electrode material arranged on the surface of the first region S1 of the first metal layer 110a, and the space utilization of the packaging structure 10 can be further improved.

[0141] For example, after the first bonding layer 120a of the first region S1 of the first metal layer 110a is removed, the first adhesive layer 130a of the first region S1 of the first metal layer 110a can be removed by laser cleaning.

[0142] In some examples, the first adhesive layer 130a is arranged in the first edge region, and the orthographic projection of the first adhesive layer 130a on the first surface is located outside the first side wall region. That is, the first adhesive layer 130a covers the first edge region and does not cover the first side wall region.

[0143] In this way, the first adhesive layer 130a is arranged in the first edge region, and the surface of the first side wall region is not provided with the first adhesive layer 130a. In the thickness direction of the first packaging film layer 12, the part of the first adhesive layer 130a opposite to the first side wall region is left as a space, which can be used to arrange the electrode material, and the arrangement amount of the electrode material inside the packaging structure 10 can be increased. In addition, the first metal layer 110a can be used as a current collector to supply power to the electrode material arranged on the surface of the first side wall region, and the space utilization of the packaging structure 10 can be further improved.

[0144] In some possible embodiments, the second bonding layer 120b is fixedly bonded to the second metal layer 110b by the adhesive layer 130, and specifically, the second bonding layer 120b is fixedly bonded to the second surface by the adhesive layer 130. The adhesive layer 130 that fixedly bonds the second bonding layer 120b to the second metal layer 110b is a second adhesive layer 130b.

[0145] In this way, the second bonding layer 120b can be arranged on the second surface, and the second bonding layer 120b is fixedly bonded to the second surface, so that the first encapsulation film layer 12 and the second encapsulation film layer 13 can be fixedly bonded to each other. When the first encapsulation film layer 12 and the second encapsulation film layer 13 are integrated, the first adhesive layer 130a and the second adhesive layer 130b are integrated.

[0146] In some possible embodiments, the first encapsulation film layer 12 further includes a first protective layer 140a, and the first protective layer 140a is arranged on a side of the first metal layer 110a that is away from the first bonding layer 120a. For example, the first metal layer 110a further includes a third surface, and the first surface and the third surface are located on two sides of the thickness direction of the first metal layer 110a respectively, and the first protective layer 140a is arranged on the third surface. The second encapsulation film layer 13 further includes a second protective layer 140b, and the second protective layer 140b is arranged on a side of the second metal layer 110b that is away from the second bonding layer 120b. For example, the second metal layer 110b further includes a fourth surface, and the second surface and the fourth surface are located on two sides of the thickness direction of the second metal layer 110b respectively, and the second protective layer 140b is arranged on the fourth surface.

[0147] In this way, the first protective layer 140a and the second protective layer 140b can play a protective role, so that the encapsulation structure 10 is less likely to be damaged.

[0148] The first protective layer 140a covers the third surface, and the second protective layer 140b covers the fourth surface.

[0149] For example, the first protective layer 140a and the second protective layer 140b are both made of insulating materials, so that the first protective layer 140a and the second protective layer 140b can also play an insulating role.

[0150] For example, the material for forming the first protective layer 140a can include, but is not limited to, polyester, polyamide, epoxy resin, acrylic resin, fluororesin, polyurethane, and a mixture thereof, and the like. For example, the first protective layer 140a can be a nylon layer.

[0151] For example, the material for forming the second protective layer 140b can include, but is not limited to, polyester, polyamide, epoxy resin, acrylic resin, fluororesin, polyurethane, and a mixture thereof, and the like. For example, the second protective layer 140b can be a nylon layer.

[0152] Exemplarily, the first protective layer 140a is fixedly bonded to the first metal layer 110a by the adhesive layer 130, and specifically, the first protective layer 140a is fixedly bonded to the third surface by the adhesive layer 130, and the adhesive layer 130 that fixedly bonds the first protective layer 140a to the first metal layer 110a is the third adhesive layer 130c.

[0153] In this way, the first protective layer 140a is conveniently arranged on the third surface.

[0154] Exemplarily, the second protective layer 140b is fixedly bonded to the second metal layer 110b by the adhesive layer 130, and specifically, the second protective layer 140b is fixedly bonded to the fourth surface by the adhesive layer 130, and the adhesive layer 130 that fixedly bonds the second protective layer 140b to the second metal layer 110b is the fourth adhesive layer 130d.

[0155] In this way, the second protective layer 140b is conveniently arranged on the fourth surface.

[0156] When the first encapsulation film layer 12 and the second encapsulation film layer 13 are in an integrated structure, the first protective layer 140a and the second protective layer 140b are in an integrated structure, and the third adhesive layer 130c and the fourth adhesive layer 130d are in an integrated structure.

[0157] In some possible embodiments, part of the pole core 200 is located in the expanded space.

[0158] In this way, the arrangement amount of the electrode material of the pole core 200 can be increased by increasing the size of the pole core 200, so as to increase the arrangement amount of the electrode material in the packaging structure 10, and thus the volumetric energy density of the battery cell can be improved, and it is relatively easy to increase the arrangement amount of the electrode material in the packaging structure 10.

[0159] Exemplarily, the arrangement amount of the electrode material of the pole core 200 can be increased by increasing the thickness of the electrode material in the pole core 200 while increasing the size of the pole core 200.

[0160] In some examples in which the pole core 200 is a jelly-roll pole core, the arrangement amount of the electrode material of the pole core 200 can be increased by increasing the length of the electrode sheet of the pole core 200 while increasing the size of the pole core 200.

[0161] In some examples in which the pole core 200 is a jelly-roll pole core, the arrangement amount of the electrode material of the pole core 200 can be increased by increasing the length of the electrode sheet of the pole core 200 while increasing the size of the pole core 200.

[0162] In some examples, the part of the pole core 200 is located in the expansion space formed at the first region S1 of the first metal layer 110a. In other words, the distance between the outer surface of the pole core 200 and the first side wall region is smaller than the distance between the side of the first bonding layer 120a facing away from the first sealing edge region and the first sealing edge region. That is, the distance between the outer surface of the pole core 200 towards the side of the first packaging film layer 12 and the outer surface of the first packaging film layer 12 at the first region S1 is smaller than the thickness of the first packaging film layer 12 at the second region S2.

[0163] The outer surface of the pole core 200 refers to the surface of the pole core 200 close to the outside of the packaging structure 10, and the outer surface of the first packaging film layer 12 refers to the surface located outside the packaging structure 10.

[0164] In this way, the size of the pole core 200 can be increased towards the side close to the first side wall region, the arrangement amount of the electrode material of the pole core 200 can be increased by increasing the size of the pole core 200, the arrangement amount of the electrode material in the packaging structure 10 can be increased, and thus the volumetric energy density of the battery cell can be increased, and it is easier to increase the arrangement amount of the electrode material in the packaging structure 10.

[0165] FIG. 5 is a schematic cross-sectional view of a pole core of a battery cell at a first region according to an embodiment of the present application.

[0166] As shown in FIG. 5, in some examples in which the part of the pole core 200 is located in the expansion space, the pole core 200 includes a second electrode sheet 210, at least part of the second electrode sheet 210 is located on the outer surface of the pole core 200 and on the side of the pole core 200 close to the first region S1. The second electrode sheet 210 includes a second current collector 211 and a third electrode material 212, and the third electrode material 212 is arranged on the inner surface of the second current collector 211.

[0167] In this way, the outermost side of the pole core 200 is free of isolation films, the number of isolation films of the pole core 200 is small, the arrangement amount of the electrode material of the pole core 200 is high, and the volumetric energy density of the battery cell can be improved.

[0168] For example, at least part of the second electrode sheet 210 can be located in the expansion space.

[0169] The second electrode sheet 210 is one of the anode electrode sheets of the pole core 200, or the second electrode sheet 210 is one of the cathode electrode sheets of the pole core 200. The second current collector 211 is electrically connected to one of the first tab 20 and the second tab 30.

[0170] The inner surface of the second current collector 211 refers to the surface of the side of the second current collector 211 facing the center of the pole core 200.

[0171] In some examples, when the pole core 200 is a laminated pole core, the outer surface of the pole core 200 on the side facing the first side wall region can be provided with the second electrode sheet 210, and the outer surface of the pole core 200 on the side away from the first side wall region can also be provided with the second electrode sheet 210.

[0172] FIG. 6 is a cross-sectional view of a pole core of an electric core according to an embodiment of the present application.

[0173] As shown in FIG. 6, in some possible embodiments, the pole core 200 includes a first separation film 220 and a third electrode sheet 230. The first separation film 220 is located on the outer surface of the pole core 200, at least part of the first separation film 220 is located on the side of the pole core 200 close to the first region S1, and the third electrode sheet 230 is arranged adjacent to the first separation film 220.

[0174] The third electrode sheet 230 is one of the anode electrode sheets of the pole core 200, or the third electrode sheet 230 is one of the cathode electrode sheets of the pole core 200, and the first separation film 220 is one of the separation films of the pole core 200.

[0175] The third electrode sheet 230 includes a third current collector 231 and a fourth electrode material 232, and the fourth electrode material 232 is arranged on both sides of the third current collector 231 in the thickness direction.

[0176] In some examples, at least part of the first separation film 220 is located on the outer surface of the pole core 200 on the side facing the first side wall region.

[0177] In some examples in which the pole core 200 is a laminated pole core, the outer surface of the pole core 200 on the side facing the first side wall region is provided with the first separation film 220, that is, the outer surface of the pole core 200 on the side facing the first region S1 of the first metal layer 110a is provided with the first separation film 220, and the electrode sheet of the pole core 200 close to the first side wall region is the third electrode sheet 230.

[0178] FIG. 7 is a cross-sectional view of another electric core according to an embodiment of the present application.

[0179] As shown in FIG. 7, and with reference to FIG. 6, in some examples, the electric core further includes a first electrode sheet 300. The first electrode sheet 300 is arranged in the sealed cavity 11, and the first electrode sheet 300 is arranged between the pole core 200 and the first region S1.

[0180] In this way, the amount of electrode material arranged in the packaging structure 10 can be increased by adding the first electrode sheet 300 between the pole core 200 and the first region S1, thereby increasing the volumetric energy density of the electric core, and it is relatively easy to increase the amount of electrode material arranged in the packaging structure 10.

[0181] One of the first electrode tab 300 and the third electrode tab 230 is a cathode electrode tab, and the other of the first electrode tab 300 and the third electrode tab 230 is an anode electrode tab, that is, the first electrode tab 300 and the third electrode tab 230 are electrode tabs with opposite polarities. The first electrode tab 300 is electrically connected to one of the first tab 20 and the second tab 30, and the third electrode tab 230 is electrically connected to the other of the first tab 20 and the second tab 30.

[0182] The first electrode tab 300 is an electrode tab independent of the electrode core 200, and the connection of the first electrode tab 300 to one of the first tab 20 and the second tab 30 can refer to the connection of the electrode tab of the electrode core 200 to the first tab 20 and the second tab 30.

[0183] For example, at least part of the first electrode tab 300 is located in the expansion space.

[0184] In some examples in which the first metal layer 110a includes the first region S1 and the second region S2, the first electrode tab 300 is provided between the electrode core 200 and the first region S1 of the first metal layer 110a, that is, the first electrode tab 300 is provided between the electrode core 200 and the first side wall region.

[0185] For example, the first electrode tab 300 includes a first current collector 310 and a first electrode material 320, the first electrode material 320 is provided on a side of the first current collector 310 close to the electrode core 200, the first current collector 310 is electrically connected to one of the first tab 20 and the second tab 30, and the third current collector 231 is electrically connected to the other of the first tab 20 and the second tab 30.

[0186] In this way, the utilization rate of the electrode material coated on the first electrode tab 300 is high, and the coating amount of the electrode material that can be utilized on the first electrode tab 300 is facilitated to be increased.

[0187] In some examples in which the first electrode tab 300 is provided between the electrode core 200 and the first side wall region, for the first electrode tab 300 between the electrode core 200 and the first side wall region, the first electrode material 320 is provided on a side of the first current collector 310 away from the first side wall region along the thickness direction of the first current collector 310.

[0188] For example, the first current collector 310 can be electrically connected to the first tab 20, and the third current collector 231 can be electrically connected to the second tab 30.

[0189] When the first electrode sheet 300 is a cathode electrode sheet, the first current collector 310 is a cathode current collector, the first electrode material 320 is a cathode electrode material, the first electrode tab 20 can be electrically connected to the cathode electrode sheet of the electrode core 200, the third electrode sheet 230 is an anode electrode sheet, the third current collector 231 is an anode current collector, the fourth electrode material 232 is an anode electrode material, and the second electrode tab 30 can be electrically connected to the anode electrode sheet of the electrode core 200.

[0190] When the first electrode sheet 300 is an anode electrode sheet, the first current collector 310 is an anode current collector, the first electrode material 320 is an anode electrode material, the first electrode tab 20 can be electrically connected to the anode electrode sheet of the electrode core 200, the third electrode sheet 230 is a cathode electrode sheet, the third current collector 231 is a cathode current collector, the fourth electrode material 232 is a cathode electrode material, and the second electrode tab 30 can be electrically connected to the cathode electrode sheet of the electrode core 200.

[0191] For example, the first current collector 310 can have a tab connecting portion which can be welded to the first electrode tab 20 or the second electrode tab 30.

[0192] FIG. 8 is a schematic view of a layer stack of a first packaging film layer provided with a second electrode material according to an embodiment of the present application, FIG. 9 is a schematic view of a cross section of another electrode core according to an embodiment of the present application, and FIG. 10 is a schematic view of a cross section of an electrode core of an electrode core according to an embodiment of the present application at a second electrode material.

[0193] As shown in FIGS. 8-10, in some examples in which the bonding layer 120 covers the second region S2 and does not cover the first region S1, the surface of the first region S1 close to the electrode core 200 is provided with the second electrode material 400.

[0194] In this way, the amount of electrode material arranged in the packaging structure 10 can be increased by arranging the electrode material on the surface of the first region S1, and thus the volumetric energy density of the electrode core can be increased. In addition, the metal layer 110 including the first region S1 and the second region S2 is used as a current collector for carrying the electrode material, the space utilization of the electrode core is high, and the amount of electrode material that can be arranged in the expanded space is large, which is conducive to the improvement of the volumetric energy density of the electrode core.

[0195] The third electrode sheet 230 is a cathode electrode sheet, and the second electrode material 400 is an anode electrode material, or the third electrode sheet 230 is an anode electrode sheet, and the second electrode material 400 is a cathode electrode material. The metal layer 110 including the first region S1 and the second region S2 is electrically connected to one of the first electrode tab 20 and the second electrode tab 30, and the third electrode sheet 230 is electrically connected to the other of the first electrode tab 20 and the second electrode tab 30.

[0196] One of the fourth electrode material 232 and the second electrode material 400 is a cathode electrode material, and the other of the fourth electrode material 232 and the second electrode material 400 is an anode electrode material, that is, the fourth electrode material 232 and the second electrode material 400 are electrode materials of opposite polarities. The metal layer 110 including the first region S1 and the second region S2 is electrically connected to one of the first tab 20 and the second tab 30, and the third current collector 331 is electrically connected to the other of the first tab 20 and the second tab 30.

[0197] In the example in which the surface of the first region S1 is provided with the second electrode material 400, the fourth electrode material 232 is provided on both sides in the thickness direction of the third current collector 231, so that the amount of electrode material applied can be larger, and the utilization rate of the electrode material applied can be higher.

[0198] In some examples in which the first metal layer 110a includes the first region S1 and the second region S2, the first side wall region is provided with the second electrode material 400, that is, the surface of the first region S1 of the first metal layer 110a close to the core 200 is provided with the second electrode material 400, the first metal layer 110a is electrically connected to one of the first tab 20 and the second tab 30, and the third electrode sheet 230 is electrically connected to the other of the first tab 20 and the second tab 30.

[0199] In this way, the amount of electrode material arranged in the packaging structure 10 can be increased by arranging the electrode material in the first side wall region, and the volumetric energy density of the core can be increased. In addition, the first metal layer 110a is used as a current collector for carrying the electrode material, the space utilization of the core is high, and the amount of electrode material that can be arranged in the part of the first bonding layer 120a that is left empty at the opposite position of the first side wall region is large, which is beneficial to the improvement of the volumetric energy density of the core.

[0200] When the fourth electrode material 232 is a cathode electrode material and the second electrode material 400 provided in the first side wall region is an anode electrode material, the first metal layer 110a can be used as an anode current collector, the first tab 20 can be electrically connected to the anode electrode sheet of the core 200, the third electrode sheet 230 is a cathode electrode sheet, the third current collector 231 is a cathode current collector, and the second tab 30 can be electrically connected to the cathode electrode sheet of the core.

[0201] When the fourth electrode material 232 is an anode electrode material and the second electrode material 400 provided in the first side wall region is a cathode electrode material, the first metal layer 110a can be used as a cathode current collector, the first tab 20 can be electrically connected to the cathode electrode sheet of the core 200, the third electrode sheet 230 is an anode electrode sheet, the third current collector 231 is an anode current collector, and the second tab 30 can be electrically connected to the anode electrode sheet of the core 200.

[0202] FIG. 11 is a schematic view of another first encapsulation film layer and second encapsulation film layer according to an embodiment of the present application, and FIG. 12 is a schematic view of another battery cell according to an embodiment of the present application.

[0203] As shown in FIGS. 11 and 12, in some possible embodiments, the metal layer 110 including the first region S1 and the second region S2 further includes a connecting portion 111 protruding from an outer edge of the second region S2, and the connecting portion 111 is located outside the sealing cavity 11, that is, the connecting portion 111 is located outside the encapsulation structure 10. The connecting portion 111 is connected to the first tab 20 or the second tab 30, so that the metal layer 110 including the first region S1 and the second region S2 is electrically connected to the first tab 20 or the second tab 30.

[0204] In this way, the metal layer 110 including the first region S1 and the second region S2 can be connected to the first tab 20 or the second tab 30 outside the encapsulation structure 10 through the connecting portion 111, so that the metal layer 110 including the first region S1 and the second region S2 is connected to the first tab 20 or the second tab 30 more easily. In addition, the connection between the metal layer 110 including the first region S1 and the second region S2 and the first tab 20 or the second tab 30 is also less likely to damage the encapsulation structure 10.

[0205] For example, the first metal layer 110a includes a connecting portion 111 protruding from an outer edge of the first edge region, that is, the first metal layer 110a includes a connecting portion 111 protruding from an outer edge of the second region S2, and the connecting portion 111 is located outside the encapsulation structure 10. The connecting portion 111 of the first metal layer 110a is connected to the first tab 20, so that the first metal layer 110a is electrically connected to the first tab 20.

[0206] In this way, the first metal layer 110a is connected to the first tab 20 outside the encapsulation structure 10 through the connecting portion 111, so that the first metal layer 110a is connected to the first tab 20 more easily. In addition, the connection between the first metal layer 110a and the first tab 20 is also less likely to damage the first encapsulation film layer 12.

[0207] For example, the connecting portion 111 of the first metal layer 110a is welded to the first tab 20.

[0208] In some possible embodiments, the first metal layer 110a is an aluminum layer, and the first packaging film layer 12 can be an aluminum-plastic film. The third electrode tab 230 arranged on the side of the pole core 200 close to the first side wall region is an anode electrode tab, the fourth electrode material 232 of the third electrode tab 230 arranged on the side of the pole core 200 close to the first side wall region is an anode electrode material, the second electrode material 400 arranged on the first side wall region is a cathode electrode material, and the first metal layer 110a can serve as a cathode current collector. The third current collector 231 of the third electrode tab 230 arranged on the side of the pole core 200 close to the first side wall region is a cathode current collector.

[0209] In this way, the second electrode material 400 arranged on the surface of the first metal layer 110a as an aluminum layer can undergo a galvanic cell reaction and an electrolytic reaction, so as to improve the volumetric energy density of the battery cell with the first metal layer 110a as an aluminum layer.

[0210] In some possible embodiments, the first metal layer 110a is a steel layer, and the first packaging film layer 12 is a steel-plastic film. The third electrode tab 230 arranged on the side of the pole core 200 close to the first side wall region is a cathode electrode tab, the fourth electrode material 232 of the third electrode tab 230 arranged on the side of the pole core 200 close to the first side wall region is a cathode electrode material, the second electrode material 400 arranged on the first side wall region is an anode electrode material, and the first metal layer 110a can serve as an anode current collector. The third current collector 231 of the third electrode tab 230 arranged on the side of the pole core 200 close to the first side wall region is a cathode current collector.

[0211] In this way, the second electrode material 400 arranged on the surface of the first metal layer 110a as a steel layer can undergo a galvanic cell reaction and an electrolytic reaction, so as to improve the volumetric energy density of the battery cell with the first metal layer 110a as a steel layer.

[0212] In some examples, the second electrode tab 30 is connected to the first metal layer 110a through an insulating medium (for example, at least one of the first bonding layer 120a and the second bonding material 31), and the second electrode tab 30 is not in direct electrical contact with the first metal layer 110a.

[0213] In some possible embodiments, at least one of the first electrode tab 20 and the second electrode tab 30 includes a connecting section 40, that is, at least one of the electrode tabs includes the connecting section 40, the connecting section 40 is located between the pole core 200 and the cavity wall of the sealed cavity 11, and the outer circumferential surface of the connecting section 40 is covered by the insulating material 50.

[0214] In this way, the problem of short circuit between the first electrode tab 20 and the second electrode tab 30 caused by the electrical contact between the connecting section 40 and the first metal layer 110a or the second metal layer 110b is less likely to occur.

[0215] For example, the second tab 30 of the battery cell includes a connecting section 40 between the electrode core 200 and the cavity wall of the sealed cavity 11, and the second tab 30 is electrically connected to the electrode plate of the battery cell close to the first region S1 of the first metal layer 110a.

[0216] In this way, the problem of short circuit between the first tab 20 and the second tab 30 due to the connecting section 40 of the second tab 30 being in electrical contact with the first metal layer 110a is less likely to occur.

[0217] For example, the insulating material 50 covering the outer circumferential surface of the connecting section 40 of the second tab 30 extends to the surface of the second bonding material 31 and covers part of the second bonding material 31.

[0218] In some examples, the first tab 20 includes a connecting section 40 between the electrode core 200 and the cavity wall of the sealed cavity 11, and the insulating material 50 covering the outer circumferential surface of the connecting section 40 of the first tab 20 extends to the surface of the first bonding material 21 and covers part of the first bonding material 21.

[0219] In some examples in which the electrode core 200 includes the second electrode plate 210, the first tab 20 and the second tab 30 are both connected to the first metal layer 110a through the insulating medium (e.g., the first bonding layer 120a), and the first tab 20 and the second tab 30 are both not in direct electrical contact with the first metal layer 110a.

[0220] In some examples in which the battery cell further includes the first electrode plate 300, the first tab 20 and the second tab 30 are both connected to the first metal layer 110a through the insulating medium (e.g., the first bonding layer 120a), and the first tab 20 and the second tab 30 are both not in direct electrical contact with the first metal layer 110a.

[0221] In some examples in which the first metal layer 110a includes the first region S1 and the second region S2, the second surface is covered by the second bonding layer 120b, that is, the second metal layer 110b does not include the first region S1 and the second region S2, and the second metal layer 110b is covered by the second bonding layer 120b.

[0222] FIG. 13 is a schematic view of a layer stack of a second encapsulation film layer according to an embodiment of the present application, FIG. 14 is a schematic view of another first encapsulation film layer and second encapsulation film layer according to an embodiment of the present application, and FIG. 15 is a schematic view of another battery cell according to an embodiment of the present application.

[0223] As shown in FIGS. 13-15, in some possible embodiments, the second metal layer 110b includes a first region S1 and a second region S2, and the second bonding layer 120b covers the second region S2 of the second metal layer 110b and does not cover the first region S1 of the second metal layer 110b, so as to form an expanded space at the first region S1 of the second metal layer 110b. At least part of the second bonding layer 120b located at the second region S2 is used for edge sealing, that is, the second bonding layer 120b located at the second region S2 is integrated with the first encapsulation film layer 12. For example, at least part of the second bonding layer 120b located at the second region S2 is integrated with the first bonding layer 120a.

[0224] In this way, while the edge sealing can be achieved by using the second bonding layer 120b, by making the second bonding layer 120b not cover the first region S1 of the second metal layer 110b, a space can be left at the first region S1 of the second metal layer 110b to form an expanded space, so that the capacity of the sealed cavity 11 can be increased on the basis of the unchanged size of the battery cell, which is conducive to increasing the amount of electrode material arranged in the sealed cavity 11, and further conducive to improving the volumetric energy density of the battery cell.

[0225] For example, the second surface includes a second edge sealing region and a second side wall region, the second surface located at the first region S1 is the second side wall region, and at least part of the second surface located at the second region S2 is the second edge sealing region. The second bonding layer 120b provided at the second edge sealing region is used for edge sealing, that is, the second bonding layer 120b provided at the second edge sealing region is combined with the first bonding layer 120a.

[0226] For example, the second edge sealing region is arranged around the outer edge of the second side wall region, and the second edge sealing region is arranged opposite to the first edge sealing region.

[0227] In some examples, the second bonding layer 120b located at the second region S2 is used for edge sealing, that is, the first region S1 of the second metal layer 110b extends to the position where the second bonding layer 120b is used for edge sealing. At this time, the second surface located at the second region S2 is the second edge sealing region, the second bonding layer 120b is arranged at the second edge sealing region, and the orthographic projection of the second bonding layer 120b on the second surface is located outside the second side wall region, that is, the second bonding layer 120b covers the second edge sealing region and does not cover the second side wall region.

[0228] In this way, the second bonding layer 120b is arranged at the second sealing edge region, and the surface of the second side wall region is not provided with the second bonding layer 120b. In the thickness direction of the second packaging film layer 13, the second bonding layer 120b leaves a space opposite the second side wall region, thereby increasing the space inside the packaging structure 10. The space left at the position opposite the second side wall region can be used to arrange electrode materials, which is conducive to increasing the arrangement amount of electrode materials inside the packaging structure 10, and in turn conducive to improving the volumetric energy density of the battery cell.

[0229] For example, the second bonding layer 120b originally covering the first region S1 of the second metal layer 110b can be removed by laser cleaning the inner surface of the second packaging film layer 13 to form an expanded space at the first region S1 of the second metal layer 110b.

[0230] The surface of the connecting section 40 is coated with the insulating material 50, which can prevent the connecting section 40 from being in electrical contact with the second metal layer 110b.

[0231] For example, the second sealing edge region can be covered by the second bonding layer 120b.

[0232] For example, when the second metal layer 110b includes the first region S1 and the second region S2, the second sealing edge region can surround the outer edge of the second side wall region, or the second sealing edge region can only surround part of the outer edge of the second side wall region. As long as the second bonding layer 120b arranged at the second sealing edge region can form a sealed cavity 11 in the packaging structure 10 after being combined with the first bonding layer 120a, the second sealing edge region can be arranged in this way. For example, when the first packaging film layer 12 and the second packaging film layer 13 are in an integrated structure, the outer edge of the second side wall region includes a second side edge integrally connected with the first packaging film layer 12, and the second sealing edge region surrounds part of the outer edge of the second side wall region excluding the second side edge.

[0233] For example, the distance between the outer edge of the second bonding layer 120b and the inner edge of the second bonding layer 120b is greater than or equal to 1 mm and less than or equal to 8 mm, that is, the width of the second bonding layer 120b is greater than or equal to 1 mm and less than or equal to 8 mm.

[0234] In this way, the first packaging film layer 12 and the second packaging film layer 13 can be combined more stably. In addition, the inner edge of the second bonding layer 120b can surround a larger space, so that the space inside the packaging structure 10 is larger, which is conducive to arranging more electrode materials.

[0235] For example, the second sealing edge region is located at the outer edge of the second surface, that is, the second bonding layer 120b is arranged at the outer edge of the second surface.

[0236] In some examples in which the second bonding layer 120b covers the second region S2 of the second metal layer 110b and does not cover the first region S1 of the second metal layer 110b, the second adhesive layer 130b covers the second region S2 of the second metal layer 110b and does not cover the first region S1 of the second metal layer 110b.

[0237] In this way, the second adhesive layer 130b can be arranged in the space left by the first region S1 of the second metal layer 110b, which facilitates increasing the amount of electrode material arranged inside the packaging structure 10. In addition, the first region S1 of the second metal layer 110b is exposed to the inner surface of the second packaging film layer 13, and then the electrode material can be arranged on the surface of the first region S1 of the second metal layer 110b, which facilitates achieving the power supply to the electrode material arranged on the surface of the first region S1 of the second metal layer 110b by the second metal layer 110b as a current collector, and further improves the space utilization of the packaging structure 10.

[0238] For example, after the second bonding layer 120b of the first region S1 of the second metal layer 110a is removed, the second adhesive layer 130b of the first region S1 of the second metal layer 110b can be removed by laser cleaning.

[0239] In some possible embodiments, the second adhesive layer 130b is arranged in the second edge region, and the orthographic projection of the second adhesive layer 130b on the second surface is located outside the second side wall region. That is, the second adhesive layer 130b covers the second edge region and does not cover the second side wall region.

[0240] In this way, the second adhesive layer 130b is arranged in the second edge region, and the surface of the second side wall region is not provided with the second adhesive layer 130b. In the thickness direction of the second packaging film layer 13, the part of the second adhesive layer 130b opposite to the second side wall region is left as a space, which can be used to arrange electrode material, facilitating increasing the amount of electrode material arranged inside the packaging structure 10. In addition, it is also convenient to achieve the power supply to the electrode material arranged on the surface of the second side wall region by the second metal layer 110b as a current collector, which further improves the space utilization of the packaging structure 10.

[0241] In some examples, part of the pole core 200 is located in the expansion space formed at the first region S1 of the second metal layer 110b. In other words, the distance between the outer surface of the pole core 200 and the second side wall region is less than the distance between the side of the second bonding layer 120b away from the second edge region and the second edge region. That is, the distance between the outer surface of the pole core 200 and the outer surface of the second packaging film layer 13 at the first region S1 is less than the thickness of the second packaging film layer 13 at the second region S2.

[0242] In this way, the size of the pole core 200 can be increased towards the second side wall region, the amount of electrode material of the pole core 200 can be increased by increasing the size of the pole core 200, the amount of electrode material in the packaging structure 10 can be increased, and the volumetric energy density of the battery cell can be increased. It is relatively easy to increase the amount of electrode material in the packaging structure 10.

[0243] When the second electrode sheet 210 is arranged on the outer surface of the pole core 200 towards the first side wall region and on the outer surface of the pole core 200 away from the first side wall region, and the first packaging film layer 12 and the second packaging film layer 13 are an integral structure, the second electrode sheet 210 arranged on the outer surface of the pole core 200 towards the first side wall region and the second electrode sheet 210 arranged on the outer surface of the pole core 200 away from the first side wall region can be electrode sheets of the same polarity, that is, the second electrode sheet 210 arranged on the outer surface of the pole core 200 towards the first side wall region and the second electrode sheet 210 arranged on the outer surface of the pole core 200 away from the first side wall region are both anode electrode sheets or both cathode electrode sheets, so as to avoid short circuit caused by the second electrode sheet 210 arranged on the outer surface of the pole core 200 towards the first side wall region and the second electrode sheet 210 arranged on the outer surface of the pole core 200 away from the first side wall region being in contact with the first metal layer 110a and the second metal layer 110b respectively.

[0244] When the second electrode sheet 210 is arranged on the outer surface of the pole core 200 towards the first side wall region and on the outer surface of the pole core 200 away from the first side wall region, and the first packaging film layer 12 and the second packaging film layer 13 are a split structure connected by an insulating medium, the second electrode sheet 210 arranged on the outer surface of the pole core 200 towards the first side wall region and the second electrode sheet 210 arranged on the outer surface of the pole core 200 away from the first side wall region can be electrode sheets of the same polarity, or the second electrode sheet 210 arranged on the outer surface of the pole core 200 towards the first side wall region and the second electrode sheet 210 arranged on the outer surface of the pole core 200 away from the first side wall region can be electrode sheets of opposite polarity.

[0245] When the second electrode sheet 210 arranged on the outer surface of the pole core 200 towards the first side wall region and the second electrode sheet 210 arranged on the outer surface of the pole core 200 away from the first side wall region are electrode sheets of the same polarity, the second electrode sheet 210 arranged on the outer surface of the pole core 200 towards the first side wall region and the second electrode sheet 210 arranged on the outer surface of the pole core 200 away from the first side wall region can be electrically connected to the first tab 20.

[0246] When the second electrode tab 210 provided on the outer surface of the jelly-roll 200 on the side facing the first side wall region and the second electrode tab 210 provided on the outer surface of the jelly-roll 200 on the side away from the first side wall region are electrode tabs of opposite polarity, the second electrode tab 210 provided on the outer surface of the jelly-roll 200 on the side facing the first side wall region can be electrically connected to the first tab 20, and the second electrode tab 210 provided on the outer surface of the jelly-roll 200 on the side away from the first side wall region can be electrically connected to the second tab 30.

[0247] FIG. 16 is a schematic cross-sectional view of another type of battery cell according to an embodiment of the present application.

[0248] As shown in FIG. 16, in some examples, the first electrode tab 300 is provided between the jelly-roll 200 and the first region S1 of the second metal layer 110b.

[0249] In this way, the amount of electrode material arranged in the packaging structure 10 can be increased by adding the first electrode tab 300 between the jelly-roll 200 and the second side wall region, and thus the volumetric energy density of the battery cell can be improved. It is relatively easy to increase the amount of electrode material arranged in the packaging structure 10.

[0250] For example, the first electrode tab 300 is provided between the jelly-roll 200 and the first region S1 of the first metal layer 110a, and between the jelly-roll 200 and the first region S1 of the second metal layer 110b.

[0251] In some examples, the jelly-roll 200 is a jelly-roll, the jelly-roll 200 includes a first separator 220 and a third electrode tab 230, a portion of the first separator 220 is located on the outer surface of the jelly-roll 200 on the side facing the first side wall region, and a portion of the first separator 220 is located on the outer surface of the jelly-roll 200 on the side facing the second side wall region, and the first electrode tab 300 is provided between the jelly-roll 200 and the first region S1 of the second metal layer 110b, that is, the first electrode tab 300 is provided between the jelly-roll 200 and the second side wall region.

[0252] In this way, when the jelly-roll 200 is a jelly-roll, the amount of electrode material arranged in the packaging structure 10 can be increased by adding the first electrode tab 300 between the jelly-roll 200 and the second side wall region, and thus the volumetric energy density of the battery cell can be improved. It is relatively easy to increase the amount of electrode material arranged in the packaging structure 10.

[0253] In some examples, the core 200 is a laminated core, the second metal layer 110b includes a first region S1 and a second region S2, the core 200 is provided with a first isolation film 220 on the outer surface of the side of the core 200 facing the second side wall region, that is, the core 200 is provided with a first isolation film 220 on the outer surface of the side of the core 200 facing the first region S1 of the second metal layer 110b, and the electrode sheet close to the second side wall region of the core 200 is a third electrode sheet 230. The first electrode sheet 300 is arranged between the core 200 and the first region S1 of the second metal layer 110b, that is, the first electrode sheet 300 is arranged between the core 200 and the second side wall region.

[0254] In this way, when the core 200 is a laminated core, the amount of electrode material arranged in the packaging structure 10 can be increased by adding an electrode sheet between the core 200 and the second side wall region, thereby increasing the volumetric energy density of the core and making it easier to arrange the electrode material in the packaging structure 10.

[0255] In some examples, the third electrode sheet 230 arranged on the side of the core 200 close to the first side wall region and the third electrode sheet 230 arranged on the side of the core 200 close to the second side wall region are electrode sheets of the same polarity, that is, the third electrode sheet 230 arranged on the side of the core 200 close to the first side wall region and the third electrode sheet 230 arranged on the side of the core 200 close to the second side wall region are both anode electrode sheets or cathode electrode sheets. At this time, the first electrode sheet 300 arranged between the core 200 and the first side wall region and the first electrode sheet 300 arranged between the core 200 and the second side wall region are electrode sheets of the same polarity, the first electrode sheet 300 arranged between the core 200 and the first side wall region and the first electrode sheet 300 arranged between the core 200 and the second side wall region can be electrically connected to the first tab 20, and the third electrode sheet 230 arranged on the side of the core 200 close to the first side wall region and the third electrode sheet 230 arranged on the side of the core 200 close to the second side wall region can be electrically connected to the second tab 30.

[0256] In some examples, the third electrode tab 230 arranged on the side of the pole core 200 close to the first side wall region and the third electrode tab 230 arranged on the side of the pole core 200 close to the second side wall region are electrode tabs of opposite polarity, that is, one of the third electrode tab 230 arranged on the side of the pole core 200 close to the first side wall region and the third electrode tab 230 arranged on the side of the pole core 200 close to the second side wall region is an anode electrode tab, and the other of the third electrode tab 230 arranged on the side of the pole core 200 close to the first side wall region and the third electrode tab 230 arranged on the side of the pole core 200 close to the second side wall region is a cathode electrode tab. In this case, the first electrode tab 300 arranged between the pole core 200 and the first side wall region and the third electrode tab 230 arranged on the side of the pole core 200 close to the second side wall region are electrically connected to the second tab 30, and the first electrode tab 300 arranged between the pole core 200 and the second side wall region and the third electrode tab 230 arranged on the side of the pole core 200 close to the first side wall region are electrically connected to the first tab 20.

[0257] When the first electrode tab 300 arranged between the pole core 200 and the first side wall region and the first electrode tab 300 arranged between the pole core 200 and the second side wall region are electrode tabs of opposite polarity, the first encapsulation film layer 12 and the second encapsulation film layer 13 can be a split structure connected by an insulating medium, so as to avoid the first electrode tab 300 arranged between the pole core 200 and the first side wall region and the first electrode tab 300 arranged between the pole core 200 and the second side wall region from being in contact with the first metal layer 110a and the second metal layer 110b respectively, thereby causing a short circuit.

[0258] FIG. 17 is a schematic view of a layer stack of a second encapsulation film layer provided with a second electrode material according to an embodiment of the application, and FIG. 18 is a schematic view of a cross section of another battery cell according to an embodiment of the application.

[0259] As shown in FIGS. 17 and 18, in some examples, the second side wall region is provided with a second electrode material 400, that is, the surface of the first region S1 of the second metal layer 110b close to the pole core 200 is provided with the second electrode material 400, and the second metal layer 110b is electrically connected to one of the first tab 20 and the second tab 30.

[0260] In this way, the amount of electrode material arranged in the encapsulation structure 10 can be increased by arranging the electrode material on the second side wall region, thereby improving the volumetric energy density of the battery cell. In addition, the second metal layer 110b is used as a current collector for carrying the electrode material, and the space utilization of the battery cell is high. The amount of electrode material that can be arranged in the space left by the second bonding layer 120b at the opposite position of the second side wall region is large, which is conducive to improving the volumetric energy density of the battery cell.

[0261] When the second electrode material 400 arranged at the second side wall region is an anode electrode material, the second metal layer 110b can serve as an anode current collector.

[0262] When the second electrode material 400 arranged at the second side wall region is a cathode electrode material, the second metal layer 110b can serve as a cathode current collector.

[0263] For example, the first side wall region and the second side wall region are both provided with the second electrode material 400.

[0264] When the core 200 is a wound core, the second electrode material 400 arranged at the first side wall region and the second electrode material 400 arranged at the second side wall region are electrode materials of the same polarity.

[0265] In some examples in which the core 200 is a laminated core, the second metal layer 110b includes a first region S1 and a second region S2, the core 200 is provided with a first separation film 220 on the outer surface of the side of the core 200 facing the second side wall region, the electrode sheet of the core 200 close to the second side wall region is a third electrode sheet 230, and the second side wall region is provided with the second electrode material 400.

[0266] In this way, when the core 200 is a laminated core, the amount of electrode material arranged in the packaging structure 10 can be increased by arranging electrode material at the second side wall region, thereby increasing the volumetric energy density of the core. In addition, the second metal layer 110b is used as a current collector for carrying electrode material, and the space utilization of the core is high. The amount of electrode material that can be arranged in the space left by the second bonding layer 120b at the opposite position of the second side wall region is large, which is conducive to the improvement of the volumetric energy density of the core.

[0267] When the first packaging film layer 12 and the second packaging film layer 13 are an integral structure, the second electrode material 400 arranged at the first side wall region and the second electrode material 400 arranged at the second side wall region are electrode materials of the same polarity, that is, the second electrode material 400 arranged at the first side wall region and the second electrode material 400 arranged at the second side wall region are both cathode electrode materials or both anode electrode materials.

[0268] When the first packaging film layer 12 and the second packaging film layer 13 are a split structure connected by an insulating medium, the second electrode material 400 arranged at the first side wall region and the second electrode material 400 arranged at the second side wall region can be electrode materials of the same polarity, or the second electrode material 400 arranged at the first side wall region and the second electrode material 400 arranged at the second side wall region can be electrode materials of opposite polarity.

[0269] When the second electrode material 400 provided in the first side wall region and the second electrode material 400 provided in the second side wall region are electrode materials of the same polarity, the first metal layer 110a and the second metal layer 110b can be electrically connected with the first tab 20.

[0270] When the second electrode material 400 provided in the first side wall region and the second electrode material 400 provided in the second side wall region are electrode materials of opposite polarities, the first metal layer 110a can be electrically connected with the first tab 20, and the second metal layer 110b can be electrically connected with the second tab 30.

[0271] FIG. 19 is a schematic view of another first encapsulation film layer and second encapsulation film layer according to an embodiment of the present application.

[0272] As shown in FIG. 19, when the first encapsulation film layer 12 and the second encapsulation film layer 13 are an integral structure, the second metal layer 110b can be electrically connected with the first tab 20 or the second tab 30 through the connecting portion 111 of the first metal layer 110a.

[0273] When the first encapsulation film layer 12 and the second encapsulation film layer 13 are separate structures and the second metal layer 110b is electrically connected with the first tab 20, the second metal layer 110b includes a connecting portion 111 protruding from the outer edge of the second edge sealing region, that is, the second metal layer 110b includes a connecting portion 111 protruding from the outer edge of the second region S2, and the connecting portion 111 of the second metal layer 110b is connected with the first tab 20, so that the second metal layer 110b is electrically connected with the first tab 20.

[0274] For example, the connecting portion 111 of the second metal layer 110b can be welded with the first tab 20.

[0275] When the first encapsulation film layer 12 and the second encapsulation film layer 13 are separate structures and the second metal layer 110b is electrically connected with the second tab 30, the second metal layer 110b includes a connecting portion 111 protruding from the outer edge of the second edge sealing region, that is, the second metal layer 110b includes a connecting portion 111 protruding from the outer edge of the second region S2, and the connecting portion 111 of the second metal layer 110b is connected with the second tab 30, so that the second metal layer 110b is electrically connected with the second tab 30.

[0276] For example, the connecting portion 111 of the second metal layer 110b can be welded with the second tab 30.

[0277] In some possible embodiments, the second metal layer 110b is an aluminum layer, and the second packaging film layer 13 is an aluminum-plastic film. The second electrode material 400 arranged at the second side wall region is a cathode electrode material, and the second metal layer 110b can serve as a cathode current collector. The third electrode tab 230 arranged at the side of the core 200 close to the second side wall region is an anode electrode tab.

[0278] In this way, the second electrode material 400 arranged on the surface of the second metal layer 110b as an aluminum layer can undergo a galvanic cell reaction and an electrolytic reaction, so as to improve the volumetric energy density of the battery cell with the second metal layer 110b as an aluminum layer.

[0279] In some possible embodiments, the second metal layer 110b is a steel layer, and the second packaging film layer 13 is a steel-plastic film. The second electrode material 400 arranged at the second side wall region is an anode electrode material, and the second metal layer 110b can serve as an anode current collector. The third electrode tab 230 arranged at the side of the core 200 close to the second side wall region is a cathode electrode tab.

[0280] In this way, the second electrode material 400 arranged on the surface of the second metal layer 110b as a steel layer can undergo a galvanic cell reaction and an electrolytic reaction, so as to improve the volumetric energy density of the battery cell with the second metal layer 110b as a steel layer.

[0281] When the second metal layer 110b is electrically connected to the second tab 30, the first tab 20 is connected to the second metal layer 110b through an insulating medium (for example, at least one of the first bonding layer 120a and the first bonding material 21), and the first tab 20 is not in direct electrical contact with the second metal layer 110b.

[0282] In some examples in which the core 200 includes the second electrode tab 210, the first tab 20 and the second tab 30 are both connected to the second metal layer 110b through an insulating medium (for example, the second bonding layer 120b), and the first tab 20 and the second tab 30 are both not in direct electrical contact with the second metal layer 110b.

[0283] In some examples in which the battery cell further includes the first electrode tab 300, the first tab 20 and the second tab 30 are both connected to the second metal layer 110b through an insulating medium (for example, the second bonding layer 120b), and the first tab 20 and the second tab 30 are both not in direct electrical contact with the second metal layer 110b.

[0284] In some examples, the first metal layer 110a and the second metal layer 110b each include a first region S1 and a second region S2.

[0285] In some other examples in which the second metal layer 110b includes the first region S1 and the second region S2, the first surface is covered by the first bonding layer 120a, that is, the first metal layer 110a does not include the first region S1 and the second region S2, and the first metal layer 110a is covered by the first bonding layer 120a.

[0286] FIG. 20 is a schematic cross-sectional view of another type of battery cell according to some embodiments of the present application.

[0287] As shown in FIG. 20, in some possible embodiments, the first region S1 is located on a large surface of the battery cell. Here, the large surface of the battery cell refers to the surface with the largest area on the packaging structure 10 of the battery cell.

[0288] In this way, the recess for forming the packaging structure 10 can be formed by stamping the first packaging film layer 12 and the second packaging film layer 13 first, the bottom wall of the recess is used to form the large surface of the battery cell, the first region S1 is located on the bottom wall of the recess, and the original bonding layer 120 on the bottom wall of the recess is easier to process (e.g., laser cleaning), making it easier to form the expanded space.

[0289] For example, the battery cell can have two large surfaces, the two large surfaces of the battery cell are located on both sides of the thickness direction of the packaging structure 10, and the first region S1 is located on one side of the sealed cavity 11 in the thickness direction of the battery cell, that is, the first region S1 is used to form the cavity wall on one side of the sealed cavity 11 in the thickness direction of the battery cell.

[0290] For example, the first region S1 of the first metal layer 110a is located on the large surface of the battery cell.

[0291] In some examples, the second region S2 includes a first sub-region S21 and a second sub-region S22, the bonding layer 120 located on the first sub-region S21 is used for edge sealing, the bonding layer 120 located on the second sub-region S22 is not used for edge sealing, the second sub-region S22 is located between the first region S1 and the first sub-region S21, and the first region S1 is connected to the first sub-region S21 through the second sub-region S22.

[0292] In this way, the second sub-region S22 that is not used for edge sealing is provided with a bonding layer, and the bonding layer 120 located on the second sub-region S22 can play an insulating and protective role on the second sub-region S22. In addition, the bonding layer 120 located on the second sub-region S22 can also improve the strength of the second sub-region S22, so that the second sub-region S22 is not easily damaged due to stretching or the like.

[0293] The two ends of the second sub-region S22 are spaced apart in the thickness direction of the battery cell, at least part of the second sub-region S22 is located on the peripheral wall of the recess formed by stamping, and the second sub-region S22 is used to form the cavity wall of the sealed cavity 11.

[0294] Exemplarily, the second region S2 of the first metal layer 110a includes a first sub-region S21 and a second sub-region S22, and the first surface of the first sub-region S21 is the first edge sealing region.

[0295] In some possible embodiments, the second region S2 is partially located on the large surface of the battery cell.

[0296] In this way, the accuracy requirement for the position of the edge of the formed expansion space is low, so that the expansion space is formed more easily. In addition, the second region extends to the large surface of the battery cell, and the corner between the large surface of the battery cell and the edge sealing position is covered by the connecting layer 120, so that the corner between the large surface of the battery cell and the edge sealing position has good strength and is not easy to be damaged due to stretching and deformation. In addition, the corner between the large surface of the battery cell and the edge sealing position has good insulation performance.

[0297] Exemplarily, the second region S2 of the first metal layer 110a is partially located on the large surface of the battery cell.

[0298] Exemplarily, the edge of the isolation film protrudes from the edge of the cathode electrode sheet of the pole core 200 and the edge of the anode electrode sheet of the pole core, so that the isolation film can better separate the cathode electrode sheet of the pole core 200 and the anode electrode sheet of the pole core 200.

[0299] Exemplarily, the part of the projection of the isolation film along the thickness direction of the battery cell can be located outside the projection of the first region S1 along the thickness direction of the battery cell, so as to facilitate improving the space utilization in the sealed cavity 11.

[0300] In some examples in which the pole core 200 is a wound pole core, the pole core 200 has a main body part and a corner part, both sides of the main body part are connected with the corner part, the projection of the main body part along the thickness direction of the battery cell is located in the projection of the first region S1 along the thickness direction of the battery cell, and the part of the projection of the corner part along the thickness direction of the battery cell is located outside the projection of the first region S1 along the thickness direction of the battery cell, so as to facilitate improving the space utilization in the sealed cavity 11 while improving the volumetric energy density of the battery cell.

[0301] In some examples in which the pole core 200 is a laminated pole core, the expansion space is provided with cathode electrode material, and the projection of the cathode electrode sheet of the pole core 200 along the thickness direction of the battery cell is located in the projection of the first region S1 along the thickness direction of the battery cell. At this time, the projection of the anode electrode sheet of the pole core 200 along the thickness direction of the battery cell can be located in the projection of the first region S1 along the thickness direction of the battery cell, or the part of the projection of the anode electrode sheet of the pole core 200 along the thickness direction of the battery cell can be located outside the projection of the first region S1 along the thickness direction of the battery cell. In this way, when the amount of arrangement of the cathode electrode material is improved by arranging the cathode electrode material in the expansion space, the cathode electrode material arranged in the expansion space is facilitated to be fully utilized.

[0302] In some examples in which the core 200 is a jelly-roll core, the expansion space is provided with anode electrode material, and the projection of the anode electrode sheet of the core 200 along the thickness direction of the core is located within the projection of the first region S1 along the thickness direction of the core. At this time, the projection of the cathode electrode sheet of the core 200 along the thickness direction of the core can be located within the projection of the first region S1 along the thickness direction of the core, and part of the projection of the cathode electrode sheet of the core 200 along the thickness direction of the core can also be located outside the projection of the first region S1 along the thickness direction of the core. In this way, when the amount of anode electrode material arranged is increased by providing anode electrode material in the expansion space, the full use of the anode electrode material provided in the expansion space is facilitated.

[0303] In some examples in which the second region S2 includes the first sub-region S21 and the second sub-region S22, the amount of electrode material arranged in the packaging structure 10 can be increased by locating part of the core 200 in the expansion space.

[0304] FIG. 21 is a cross-sectional view of another type of core provided by an embodiment of the application.

[0305] As shown in FIG. 21, in some examples in which the second region S2 includes the first sub-region S21 and the second sub-region S22, the amount of electrode material arranged in the packaging structure 10 can be increased by providing the first electrode sheet 300 between the core 200 and the first region S1.

[0306] FIG. 22 is a cross-sectional view of another type of core provided by an embodiment of the application.

[0307] As shown in FIG. 22, in some examples in which the second region S2 includes the first sub-region S21 and the second sub-region S22, the amount of electrode material arranged in the packaging structure 10 can be increased by providing the second electrode material 400 on the surface of the first region S1 close to the core 200.

[0308] FIG. 23 is a cross-sectional view of another type of core provided by an embodiment of the application.

[0309] As shown in FIG. 23, in some examples in which the bonding layer 120 covers the second region S2 and does not cover the first region S1, the thickness of the metal layer 110 located in the first region S1 is less than the thickness of the metal layer 110 located in the second region S2.

[0310] In this way, the part of the metal layer 110 vacated in the first region S1 can be used to arrange electrode material, thereby facilitating further increasing the amount of electrode material arranged inside the packaging structure 10.

[0311] Exemplarily, after the bonding layer 120 of the first region S1 is removed, the metal layer 110 of the first region S1 can be thinned by laser cleaning.

[0312] In some examples in which the first metal layer 110a includes the first region S1 and the second region S2, the thickness of the first metal layer 110a located at the first region S1 is less than the thickness of the first metal layer 110a located at the second region S2.

[0313] In some examples in which the thickness of the metal layer 110 located at the first region S1 is less than the thickness of the metal layer 110 located at the second region S2, the surface of the first region S1 close to the core 200 can be provided with the second electrode material 400 to increase the arrangement amount of the electrode material of the core.

[0314] Exemplarily, to facilitate the provision of the second electrode material 400 on the surface of the first region S1 close to the core 200, the metal layer 110 can be placed in an inert gas environment when the first region S1 of the metal layer 110 is subjected to laser cleaning, so that the surface of the first region S1 close to the core 200 is less likely to be oxidized by laser cleaning, thereby facilitating the provision of the second electrode material 400 on the surface of the first region S1 close to the core 200 after laser cleaning.

[0315] FIG. 24 is a schematic cross-sectional view of another core provided by an embodiment of the present application.

[0316] As shown in FIG. 24, in some examples in which the thickness of the metal layer 110 located at the first region S1 is less than the thickness of the metal layer 110 located at the second region S2, the arrangement amount of the electrode material in the packaging structure 10 can be increased by placing part of the core 200 in the expanded space.

[0317] In some examples in which the bonding layer 120 covers the second region S2 and does not cover the first region S1, the surface of the first region S1 close to the core 200 is covered with the oxidation layer 150. That is, the oxidation layer 150 and the bonding layer 120 are located on the same side of the metal layer 110.

[0318] In this way, the oxidation layer 150 formed can increase the strength of the packaging structure 10 at the first region S1, so that the packaging structure 10 is less likely to be damaged.

[0319] Exemplarily, the oxidation layer 150 can be formed on the surface of the metal layer 110 when the metal layer 110 is subjected to laser cleaning.

[0320] Exemplarily, the surface of the first region S1 of the first metal layer 110a close to the core 200 is covered with the oxidation layer 150, and the oxidation layer 150 covering the surface of the first region S1 of the first metal layer 110a close to the core 200 is a first oxidation layer 150a.

[0321] For example, the first packaging film layer 12 is an aluminum-plastic film, the first metal layer 110a is an aluminum layer, and the first oxide layer 150a is an aluminum oxide layer.

[0322] In some examples in which the surface of the first region S1 is covered with the oxide layer 150, the amount of electrode material arranged in the packaging structure 10 can be increased by locating part of the pole core 200 in the expansion space.

[0323] FIG. 25 is a cross-sectional view of another type of battery cell provided by an embodiment of the present application.

[0324] As shown in FIG. 25, in some examples in which the thickness of the metal layer 110 located in the first region S1 is less than the thickness of the metal layer 110 located in the second region S2, the amount of electrode material arranged in the packaging structure 10 can be increased by arranging the first electrode sheet 300 between the pole core 200 and the first region S1.

[0325] In some examples in which the surface of the first region S1 is covered with the oxide layer 150, the amount of electrode material arranged in the packaging structure 10 can be increased by arranging the first electrode sheet 300 between the pole core 200 and the first region S1.

[0326] FIG. 26 is a cross-sectional view of another type of battery cell provided by an embodiment of the present application.

[0327] As shown in FIG. 26, in some examples, the first region S1 of the second metal layer 110b is located on the large face of the battery cell.

[0328] In some examples in which the second region S2 of the first metal layer 110a includes the first sub-region S21 and the second sub-region S22, the second region S2 of the second metal layer 110b also includes the first sub-region S21 and the second sub-region S22, and the second surface located in the first sub-region S21 is the second edge sealing region.

[0329] When the second region S2 of the second metal layer 110b includes the first sub-region S21 and the second sub-region S22, the structure of the pole core 200 at the expansion space of the second packaging film layer 13 can be arranged in the same manner as the structure of the pole core 200 at the expansion space of the first packaging film layer 12.

[0330] In other examples in which the second region S2 of the first metal layer 110a includes the first sub-region S21 and the second sub-region S22, the second region S2 of the second metal layer 110b can also not include the first sub-region S21 and the second sub-region S22, and the second bonding layer 120b located in the second region S2 is used for edge sealing. In this case, the second surface located in the second region S2 is the second edge sealing region.

[0331] FIG. 27 is a cross-sectional view of another battery cell according to embodiments of the present application.

[0332] As shown in FIG. 27, in some possible embodiments, the bonding layer 120 covers the first region S1 and the second region S2, and the thickness of the bonding layer 120 covering the first region S1 is less than the thickness of the bonding layer 120 covering the second region S2, so as to form an expanded space at the first region S1.

[0333] In this way, while the edge can be sealed by the bonding layer 120, the space at the first region S1 can be left out by thinning the bonding layer 120 arranged at the first region S1, so as to form an expanded space, which increases the capacity of the sealed cavity 11, facilitates to increase the arrangement amount of the electrode material in the sealed cavity 11, and further facilitates to increase the volumetric energy density of the battery cell. In addition, the bonding layer 120 at the first region S1 can play a role in improving strength and insulation protection.

[0334] For example, the thickness of the first bonding layer 120a covering the first region S1 of the first metal layer 110a is less than the thickness of the first bonding layer 120a covering the second region S2 of the first metal layer 110a, so as to form an expanded space at the first region S1 of the first metal layer 110a. In this way, while the edge can be sealed by the first bonding layer 120a, the space at the first region S1 of the first metal layer 110a can be left out by thinning the bonding layer 120 arranged at the first region S1, so as to form an expanded space, which increases the capacity of the sealed cavity 11, facilitates to increase the arrangement amount of the electrode material in the sealed cavity 11, and further facilitates to increase the volumetric energy density of the battery cell. The bonding layer 120 at the first region S1 of the first metal layer 110a can play a role in improving strength and insulation protection.

[0335] For example, the first bonding layer 120a covering the first region S1 of the first metal layer 110a can be thinned by laser cleaning the inner surface of the first packaging film layer 12, so as to form an expanded space at the first region S1 of the first metal layer 110a.

[0336] In the example where the thickness of the bonding layer 120 covering the first region S1 is less than the thickness of the bonding layer 120 covering the second region S2, and the second region S2 includes a second sub-region S22, the thickness of the bonding layer 120 covering the first region S1 is less than the thickness of the bonding layer 120 covering the second sub-region S22, so that the bonding layer 120 at the second sub-region S22 can play a better role in improving strength and insulation protection.

[0337] In some examples in which the thickness of the bonding layer 120 covering the first region S1 is less than the thickness of the bonding layer 120 covering the second region S2, the amount of electrode material arranged within the packaging structure 10 can be increased by providing the first electrode sheet 300 between the pole core 200 and the first region S1.

[0338] In some examples in which the thickness of the bonding layer 120 covering the first region S1 is less than the thickness of the bonding layer 120 covering the second region S2, the amount of electrode material arranged within the packaging structure 10 can be increased by locating a portion of the pole core 200 within the expanded space.

[0339] In some examples in which the thickness of the first bonding layer 120a covering the first region S1 of the first metal layer 110a is less than the thickness of the first bonding layer 120a covering the second region S2 of the first metal layer 110a, the first adhesive layer 130a covers the first region S1 and the second region S2 of the first metal layer 110a.

[0340] In some examples in which the thickness of the first bonding layer 120a covering the first region S1 of the first metal layer 110a is less than the thickness of the first bonding layer 120a covering the second region S2 of the first metal layer 110a, the second bonding layer 120b can be a structure of equal thickness covering the second metal layer 110b.

[0341] In other examples in which the thickness of the first bonding layer 120a covering the first region S1 of the first metal layer 110a is less than the thickness of the first bonding layer 120a covering the second region S2 of the first metal layer 110a, the thickness of the second bonding layer 120b covering the first region S1 of the second metal layer 110b is less than the thickness of the second bonding layer 120b covering the second region S2 of the second metal layer 110b. At this time, the structure at the expanded space of the pole core 200 and the second packaging film layer 13 can be provided with reference to the structure at the expanded space of the pole core 200 and the first packaging film layer 12.

[0342] In the description of the embodiments of the present application, it should be noted that unless specifically defined and limited otherwise, the terms "mount", "connect", "connection" should be understood broadly, for example, can be fixed connection, can be indirectly connected through an intermediate medium, can be internal communication of two elements or interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0343] In the embodiments of the present application or the devices or elements implied by the embodiments of the present application must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the embodiments of the present application. In the description of the embodiments of the present application, the meaning of "a plurality of" is two or more, unless otherwise specified and limited.

[0344] The terms "first", "second", "third", "fourth" and the like in the description and in the claims of the present application, and above-described drawings, if any, are used to distinguish between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the use of the terms so construed herein can be interchanged, under appropriate circumstances, and that the embodiments of the present application described herein are capable of

[0345] The term "a plurality" or "a plurality of" means two or more. The term "and / or" herein is merely an associative relationship of the associated objects, and means that there can be three relationships, for example, A and / or B, which can mean that A exists alone, A and B exist together, and B exists alone. In addition, the character " / " herein generally means that the front and rear associated objects are in an "or" relationship; in the formula, the character " / " means that the front and rear associated objects are in a "division" relationship.

[0346] It can be understood that various numerical numbers involved in the embodiments of the present application are only distinguished for convenience of description, and do not limit the scope of the embodiments of the present application.

[0347] It can be understood that the size of the serial number of each process in the embodiments of the present application does not mean the order of execution, and the execution order of each process should be determined according to its function and inherent logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

Claims

1. An electric cell, characterized by, The first encapsulation film layer (12), the second encapsulation film layer (13) and the pole core (200) are included. At least one of the first encapsulation film layer (12) and the second encapsulation film layer (13) includes a metal layer and a bonding layer. The metal layer includes a first region (S1) and a second region (S2), and the bonding layer covers the second region (S2) and does not cover the first region (S1), or the thickness of the bonding layer covering the first region (S1) is less than the thickness of the bonding layer covering the second region (S2). At least part of the bonding layer located in the second region (S2) is used for edge sealing, so that the first encapsulation film layer (12) and the second encapsulation film layer (13) form a sealed cavity (11), and the pole core (200) is arranged in the sealed cavity (11).

2. The electric cell of claim 1, wherein, The first region (S1) is located on a large surface of the pole core.

3. The cell of claim 1 or 2, wherein, Part of the second region (S2) is located on a large surface of the pole core.

4. The cell of any of claims 1-3, wherein, When the bonding layer covers the second region (S2) and does not cover the first region (S1), the thickness of the metal layer located in the first region (S1) is less than the thickness of the metal layer located in the second region (S2).

5. The cell of claim 1 or 2, wherein, The second region (S2) is located outside the edge of the first region (S1), and the bonding layer located in the second region (S2) is used for edge sealing.

6. The cell of any of claims 1-4, wherein, The second region (S2) includes a first sub-region (S21) and a second sub-region (S22), the bonding layer located in the first sub-region (S21) is used for edge sealing, the bonding layer located in the second sub-region (S22) is not used for edge sealing, and the second sub-region (S22) is located between the first region (S1) and the first sub-region (S21).

7. The electric cell of claim 6, wherein, When the thickness of the bonding layer covering the first region (S1) is less than the thickness of the bonding layer covering the second region (S2), the thickness of the bonding layer covering the first region (S1) is less than the thickness of the bonding layer covering the second sub-region (S22).

8. The cell of any of claims 1-6, wherein, When the bonding layer covers the second region (S2) and does not cover the first region (S1), a surface of the first region (S1) close to the pole core (200) is covered with an oxidation layer (150).

9. The cell of any of claims 1-8, wherein, A first electrode sheet (300) is further included. The first electrode sheet (300) is arranged in the sealed cavity (11), and the first electrode sheet (300) is arranged between the pole core (200) and the first region (S1).

10. The electric cell of claim 9, wherein, The first electrode sheet (300) includes a first current collector (310) and a first electrode material (320), and the first electrode material (320) is arranged on one side of the first current collector (310) close to the pole core (200).

11. The cell of any of claims 1-6, wherein, When the bonding layer covers the second region (S2) and does not cover the first region (S1), a surface of the first region (S1) close to the pole core (200) is provided with a second electrode material (400).

12. The electric cell of claim 11, wherein, A pole lug is further included. The metal layer comprises a connecting part (111) protruding from the outer edge of the second area (S2), the connecting part (111) is located outside the sealed cavity (11), and the connecting part (111) is connected with the tab.

13. The electric cell of claim 11 or 12, wherein, The metal layer is an aluminum layer, and the second electrode material (400) is a cathode electrode material.

14. The cell of claim 11 or 12, wherein, The metal layer is a steel layer, and the second electrode material (400) is an anode electrode material.

15. A battery, characterized by The battery cell comprises the battery cell as claimed in any one of claims 1-14.

16. A battery pack, characterized by The battery management system comprises the battery cell as claimed in any one of claims 1-14. The battery cell is electrically connected with the battery management system.

17. An electrical device, characterized by The battery or the battery pack comprises the battery cell as claimed in claim 15 or the battery cell as claimed in claim 16.

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