Battery cell, battery device, and electric device

Abstract

The application provides a battery cell, a battery device and a power consumption device. The battery cell comprises a shell, an electrode assembly and a support, the shell has a first wall, and the electrode assembly is accommodated in the shell. The electrode assembly comprises a flat portion, the flat portion comprises a first pole segment and a second pole segment with opposite polarities, and the first pole segment and the second pole segment are arranged in a stacking mode along the thickness direction of the first wall. The support is supported between the first wall and the electrode assembly along the thickness direction of the first wall, the support comprises a first support body and a support portion connected with each other, and the support portion is arranged on at least one side of the first support body. The support portion has an abutting area farthest from the first support body, the abutting area abuts against the electrode assembly or the first wall, and a gap is formed between the abutting area and the first support body. In the initial stage of the cycle of the battery cell, the support can constrain the electrode assembly, delay the expansion process of the electrode assembly and prolong the service life of the battery cell. In the later stage of the cycle of the battery cell, the support portion is easily crushed to provide expansion space for the electrode assembly.

Description

Technical Field

[0001] This application relates to the field of batteries, and more specifically, to a battery cell, a battery device, and an electrical device. Background Technology

[0002] Batteries are widely used in the new energy field, such as in electric vehicles and new energy vehicles, which have become a new trend in the automotive industry. The development of battery technology must consider multiple design factors simultaneously, such as energy density, discharge capacity, and charge / discharge rate. Additionally, battery cycle life must be considered. However, currently, the cycle life of batteries is relatively short. Utility Model Content

[0003] The purpose of this application is to provide a battery cell, a battery device, and an electrical device, which aims to improve the problem of short cycle life of batteries in related technologies.

[0004] In a first aspect, embodiments of this application provide a battery cell, the battery cell including a housing, an electrode assembly, and a support member, the housing having a first wall; the electrode assembly being housed within the housing, the electrode assembly including a flat portion, the flat portion including a first electrode segment and a second electrode segment with opposite polarities, the first electrode segment and the second electrode segment being stacked along the thickness direction of the first wall; the support member being supported between the first wall and the electrode assembly along the thickness direction of the first wall, the support member including a connected first support body and a support portion, the support portion being disposed on at least one side of the first support body along the thickness direction of the first wall, the support portion having an abutment area furthest from the first support body, the abutment area abutting against the electrode assembly or the first wall, the abutment area having a gap with the first support body.

[0005] In the above technical solution, a support member is provided between the first wall and the electrode assembly. This support member abuts against the gap between the electrode assembly and the first wall, filling the gap between them. In the early stages of battery cell cycling, the support member constrains the electrode assembly, improving electrode wrinkling, suppressing electrode thickness growth, delaying electrode expansion, and extending battery cell lifespan. In the later stages of battery cell cycling, due to the gap between the abutment area of ​​the support member and the first support body, the support member is easily crushed under the expansion force applied by the electrode assembly, thus providing expansion space for the electrode assembly. Furthermore, the support member between the first wall and the electrode assembly provides support to the first wall, making it less prone to deformation under external impact. Moreover, during the formation process, the support member constrains the electrode assembly, helping to reduce gas residue and lowering the risk of defects such as purple spots and gas marks on the electrode.

[0006] As an optional technical solution in this application embodiment, along the thickness direction of the first wall, the support portion is disposed on the side of the first support body facing the first wall, and the abutment area abuts against the first wall.

[0007] In the above technical solution, the support part is disposed on the side of the first support body facing the first wall along the thickness direction of the first wall, and the abutment area abuts against the first wall, so that the first support body can abut against the electrode assembly. Compared with the support part, the first support body can better support the electrode assembly, which is beneficial to reduce the stress on the electrode assembly, reduce the risk of damage to the electrode assembly, and extend the life of the battery cell.

[0008] As an optional technical solution in this application embodiment, the projection of the straight portion is completely located within the first support body along the thickness direction of the first wall.

[0009] In the above technical solution, the projection of the straight portion along the thickness direction of the first wall is completely inside the first support body, so that the first support body can better support the electrode assembly, reduce the stress on the electrode assembly, reduce the risk of damage to the electrode assembly, and extend the life of the battery cell.

[0010] As an optional technical solution in this application embodiment, the support part includes at least one support rib, and the support rib is inclinedly disposed on the first support body.

[0011] In the above technical solution, the support portion includes at least one support rib inclinedly disposed on the first support body. During the initial cycling phase of the battery cell, the support rib experiences relatively low stress and can maintain its original shape, allowing the support to effectively constrain the electrode assembly, suppressing electrode thickness growth, delaying the expansion process of the electrode assembly, and extending the battery cell's lifespan. During the later cycling phase, the support rib experiences greater expansion force from the electrode assembly, making it more susceptible to crushing and thus providing expansion space for the electrode assembly.

[0012] As an optional technical solution in this application embodiment, the first support body has a first surface along the thickness direction of the first wall, the support rib is connected to the first surface, and the angle between the extension direction of the support rib and the first surface is α, satisfying: 20°≤α≤70°, and optionally, 30°≤α≤60°.

[0013] In the above technical solution, when α ≤ 70°, the angle between the extension direction of the support rib and the first surface is small, which facilitates the crushing of the support rib in the later stages of battery cell cycling, thereby providing expansion space for the electrode assembly. When α ≥ 20°, the angle between the extension direction of the support rib and the first surface is not too small. On the one hand, this allows the support rib to withstand a certain amount of pressure, thus facilitating the support member to provide better constraint for the electrode assembly in the early stages of battery cell cycling. On the other hand, when the length of the support rib along its extension direction is the same, when α ≥ 20°, the space occupied by the support rib along the thickness direction of the first wall is larger, which can better fill the gap between the electrode assembly and the first wall, thus facilitating the support member to provide better constraint for the electrode assembly in the early stages of battery cell cycling, and providing a larger expansion space after the support rib is crushed. Therefore, when 20° ≤ α ≤ 70°, it is beneficial for the support member to provide better constraint for the electrode assembly in the early stages of battery cell cycling, and also beneficial for providing a larger expansion space after the support rib is crushed.

[0014] When α ≤ 60°, the angle between the extension direction of the support rib and the first surface is smaller, making it easier for the support rib to be crushed in the later stages of battery cell cycling, thus providing expansion space for the electrode assembly. When α ≥ 30°, the angle between the extension direction of the support rib and the first surface is not too small. On the one hand, this allows the support rib to withstand a certain amount of pressure, thus facilitating better constraint of the electrode assembly by the support component in the early stages of battery cell cycling. On the other hand, with the same length of the support rib along its extension direction, when α ≥ 30°, the space occupied by the support rib along the thickness direction of the first wall is larger, which can better fill the gap between the electrode assembly and the first wall, thus facilitating better constraint of the electrode assembly by the support component in the early stages of battery cell cycling, and providing greater expansion space after the support rib is crushed. Therefore, when 30° ≤ α ≤ 60°, it is more conducive to the support component providing better constraint of the electrode assembly in the early stages of battery cell cycling, and also more conducive to providing greater expansion space after the support rib is crushed.

[0015] As an optional technical solution in this application embodiment, the thickness of the first support body is H1, and the thickness of the support rib is H2, satisfying: 0.5≤H2 / H1≤3, and optionally, 1.5≤H2 / H1≤2.5.

[0016] In the above technical solution, when H2 / H1≥0.5, the ratio of the thickness of the supporting rib to the thickness of the first support body is relatively large, resulting in a thicker supporting rib that can withstand a certain amount of pressure. This facilitates better constraint of the electrode assembly by the support component during the initial cycle of the battery cell. When H2 / H1≤3, the ratio of the thickness of the supporting rib to the thickness of the first support body is not too large, preventing the supporting rib from becoming excessively thick. This allows the supporting rib to be crushed in the later stages of battery cell cycling, thus providing expansion space for the electrode assembly. Therefore, when 0.5≤H2 / H1≤3, it is beneficial for the support component to provide better constraint of the electrode assembly during the initial cycle of the battery cell, and also for providing greater expansion space after the supporting rib is crushed.

[0017] When H2 / H1 ≥ 1.5, the ratio of the thickness of the support rib to the thickness of the first support body is larger, resulting in a thicker support rib that can withstand certain pressure. This facilitates better constraint of the electrode assembly by the support component during the initial cycle of the battery cell. Furthermore, since the support rib is the main load-bearing part of the support component, the first support body is less prone to damage compared to the support rib. Making the first support body thinner reduces its occupation of the internal space of the battery cell, which is beneficial for improving the energy density of the battery cell. It also provides greater expansion space after the support component is crushed. When H2 / H1 ≤ 2.5, the ratio of the thickness of the support rib to the thickness of the first support body is not too large, preventing the support rib from becoming excessively thick. This facilitates the crushing of the support rib during the later stages of battery cell cycle, thus providing expansion space for the electrode assembly. Therefore, when 1.5 ≤ H2 / H1 ≤ 2.5, it is beneficial for both the support component to provide better constraint of the electrode assembly during the initial cycle of the battery cell and to provide greater expansion space after the support rib is crushed.

[0018] As an optional technical solution in this application embodiment, the thickness of the first support body is H1, which satisfies: 0.1mm≤H1≤0.5mm, and optionally, 0.2mm≤H1≤0.4mm.

[0019] In the above technical solution, when H1 ≥ 0.1 mm, the thickness of the first support is relatively large, giving it high strength and reducing the risk of damage. This allows the first support to better support the electrode assembly, reducing stress on the electrode assembly and lowering the risk of damage. When H1 ≤ 0.5 mm, the thickness of the first support is not excessive, reducing its encroachment on the internal space of the battery cell, improving the energy density of the battery cell, and providing greater expansion space after the support is crushed. Therefore, when 0.1 mm ≤ H1 ≤ 0.5 mm, it not only reduces the risk of damage to the first support and the electrode assembly, but also improves the energy density of the battery cell and provides greater expansion space after the support is crushed.

[0020] When H1 ≥ 0.2 mm, the thickness of the first support is greater, resulting in higher strength and reducing the risk of its destruction. This allows the first support to better support the electrode assembly, reducing stress on the assembly and minimizing the risk of damage. When H1 ≤ 0.4 mm, the thickness of the first support is not excessive, reducing its encroachment on the internal space of the battery cell. This helps increase the energy density of the battery cell and provides greater expansion space after the support is crushed. Therefore, when 0.2 mm ≤ H1 ≤ 0.4 mm, it is more conducive to reducing the risk of damage to the first support and the electrode assembly, while also increasing the energy density of the battery cell and providing greater expansion space after the support is crushed.

[0021] As an optional technical solution in this application embodiment, the thickness of the supporting rib is H2, which satisfies: 0.15mm≤H2≤1.5mm, and optionally, 0.3mm≤H2≤0.8mm.

[0022] In the above technical solution, when H2 ≥ 0.15 mm, the support rib is relatively thick, allowing it to withstand a certain amount of pressure. This facilitates the support component's effective constraint on the electrode assembly during the initial cycle of the battery cell. When H2 ≤ 1.5 mm, the support rib is not excessively thick, allowing it to be crushed during the later stages of battery cell cycle formation, thus providing expansion space for the electrode assembly. Therefore, when 0.15 mm ≤ H2 ≤ 1.5 mm, the support component effectively constrains the electrode assembly during the initial cycle of the battery cell and provides ample expansion space after the support rib is crushed.

[0023] When H2 ≥ 0.3 mm, the support ribs are thicker, allowing them to withstand certain pressure and thus providing better constraint on the electrode assembly during the initial cycling phase of the battery cell. When H2 ≤ 0.8 mm, the support ribs are not excessively thick, allowing them to be crushed during the later cycling phase of the battery cell, providing expansion space for the electrode assembly. Therefore, when 0.3 mm ≤ H2 ≤ 0.8 mm, it is more conducive to the support component providing better constraint on the electrode assembly during the initial cycling phase of the battery cell, and also more conducive to providing greater expansion space after the support ribs are crushed.

[0024] As an optional technical solution in this application embodiment, along the thickness direction of the first wall, the supporting rib is disposed on the side of the first support body facing the first wall, the abutting area abuts against the first wall, and along the thickness direction of the supporting rib, the supporting rib includes a second surface, the second surface is disposed facing the first wall, the abutting area has a first guiding surface, the first guiding surface is connected to the second surface, and the first guiding surface includes an arc surface and / or an inclined plane.

[0025] In the above technical solution, by providing a first guiding surface, during the insertion of the support member into the casing, the first guiding surface can abut against the inner surface of the first wall, reducing the stress of the support ribs on the first wall and lowering the risk of metal debris generated by the support ribs scraping against the first wall. During the use of the battery cell, the first guiding surface can abut against the inner surface of the first wall, reducing the stress of the support ribs on the first wall and lowering the risk of metal debris generated by the support ribs scraping against the first wall.

[0026] As an optional technical solution in this application embodiment, the outer shell includes a housing and an end cap. The housing has an opening at one end along a first direction, and the end cap closes the opening. The housing includes a first wall. Along the thickness direction of the first wall, a support rib is disposed on the side of the first support body facing the first wall. The abutment area abuts against the first wall. The support rib includes a first end disposed opposite to the abutment area. The first end is connected to the first support body. Along the first direction, the abutment area is closer to the end cap than the first end. The first direction is perpendicular to the thickness direction of the first wall.

[0027] In the above technical solution, the abutment area is closer to the end cap than the first end, that is, the support rib is inclined from the first support body towards the end cap. In this way, when the support is inserted into the shell, the support rib can guide it and facilitate the insertion of the support into the shell.

[0028] As an optional technical solution in this application embodiment, the outer shell includes a second wall, the second wall and the electrode assembly are disposed opposite to each other along a first direction, the first direction being perpendicular to the thickness direction of the first wall; the support portion includes a plurality of support ribs, each support rib including a first end disposed opposite to the abutment area, the first end being connected to the first support body, the abutment area of ​​one support rib being closer to the second wall than the first end, and the abutment area of ​​another support rib being farther away from the second wall than the first end.

[0029] In the above technical solution, the support includes multiple support ribs. One support rib is inclined from the first support towards the second wall, and another support rib is inclined from the first support away from the second wall. This allows the support to withstand greater pressure, thus facilitating better constraint of the electrode assembly during the initial cycling phase of the battery cell. The support can still be crushed during the later stages of battery cell cycling, providing expansion space for the electrode assembly.

[0030] As an optional technical solution in this application embodiment, the support portion includes an arc-shaped portion, which is connected to the first support body.

[0031] In the above technical solution, the support includes an arc-shaped portion, which can withstand greater pressure, thus facilitating better constraint of the electrode assembly by the support during the initial stage of battery cell cycling. The support can still be crushed in the later stages of battery cell cycling, thereby providing expansion space for the electrode assembly.

[0032] As an optional technical solution in this application embodiment, along the thickness direction of the first wall, the arc-shaped portion includes an inner arc surface and an outer arc surface disposed opposite to each other. The inner arc surface faces the first support body, and a portion of the outer arc surface abuts against the electrode assembly or the first wall. Along the extension direction of the arc-shaped portion, at least one end of the arc-shaped portion is connected to the first support body.

[0033] In the above technical solution, the arc-shaped portion is roughly arched. When one end of the arc-shaped portion is connected to the first support body and the other end is a free end, the support member can still constrain the electrode assembly in the early stages of battery cell cycling. The support member is more easily crushed in the later stages of battery cell cycling, thus providing expansion space for the electrode assembly. When both ends of the arc-shaped portion are connected to the first support body, the arc-shaped portion can withstand greater pressure, thus facilitating better constraint of the electrode assembly by the support member in the early stages of battery cell cycling. The support member can still be crushed in the later stages of battery cell cycling, thus providing expansion space for the electrode assembly.

[0034] As an optional technical solution in this application embodiment, both ends of the arc-shaped portion are connected to the first support body along the extension direction of the arc-shaped portion.

[0035] In the above technical solution, both ends of the arc-shaped portion along its extension direction are connected to the first support. The arc-shaped portion can withstand greater pressure, thus facilitating better constraint of the electrode assembly by the support component during the initial stage of battery cell cycling. The support component can still be crushed during the later stage of battery cell cycling, thereby providing expansion space for the electrode assembly.

[0036] As an optional technical solution in this application embodiment, the support portion has a first weak portion, which is configured to be destroyed when the expansion force applied by the electrode assembly reaches a threshold.

[0037] In the above technical solution, by setting a first weak part on the support, the first weak part can be destroyed when the expansion force applied by the electrode assembly reaches a threshold, thereby facilitating the crushing of the support in the later stage of battery cell cycle, thus providing expansion space for the electrode assembly.

[0038] As an optional technical solution in this application embodiment, the support member includes a plurality of support portions, which are arranged along a first direction, the first direction being perpendicular to the thickness direction of the first wall.

[0039] In the above technical solution, by setting multiple support parts, the multiple support parts can cooperate to support the first support body, making the first support body more stable. In addition, the multiple support parts can disperse the expansion force applied by the electrode assembly, so that the support can better constrain the electrode assembly in the early stage of battery cell cycling. The support can still be crushed in the later stage of battery cell cycling, thereby providing expansion space for the electrode assembly.

[0040] As an optional technical solution in this application embodiment, the first support body has a second weak part, and along the first direction, the second weak part is disposed between two adjacent support parts.

[0041] In the above technical solution, during the later stages of battery cell cycling, the electrode assembly expands, causing the surface of the electrode assembly facing the first wall to gradually bend into an arc shape. By providing a second weak point on the first support, the first support can deform during the later stages of battery cell cycling, thereby adapting to the deformation of the electrode assembly's surface facing the first wall to a certain extent, reducing stress on the electrode assembly, and lowering the risk of electrode assembly damage.

[0042] As an optional technical solution in this application embodiment, the first support body is provided with a first groove, and the bottom wall of the first groove includes the second weak part.

[0043] In the above technical solution, the second weak part is formed by setting a first groove on the first support body, which is simple, convenient and easy to manufacture.

[0044] As an optional technical solution in this application embodiment, the first groove extends along the second direction, and the first direction, the second direction and the thickness direction of the first wall are perpendicular to each other.

[0045] In the above technical solution, the first groove extends along the second direction, and correspondingly, the second weak part also extends along the second direction, which makes it easier for the first support to deform in the later stage of the battery cell cycle, thereby adapting to the deformation of the electrode assembly's surface facing the first wall to a certain extent.

[0046] As an optional technical solution in this application embodiment, along the thickness direction of the first wall, the support portion is disposed on the side of the first support body facing the first wall, the abutment area abuts against the first wall, and the first groove and the support portion are disposed on the surface of the first support body facing the first wall.

[0047] In the above technical solution, the first groove and the support part are both provided on the surface of the first support body facing the first wall, which helps to keep the surface of the first support body away from the first wall flat, thereby facilitating the first support body to better support the electrode assembly, reducing the stress on the electrode assembly, and reducing the risk of damage to the electrode assembly.

[0048] As an optional technical solution in this application embodiment, the first support body includes a first surface and multiple side surfaces. The support portion is disposed on the first surface, and the multiple side surfaces surround the first surface. At least one set of two adjacent side surfaces are connected by a rounded corner surface.

[0049] In the above technical solution, by connecting at least one set of two adjacent sides through a rounded corner, it is beneficial to reduce the risk of the first support scraping against the first wall and generating metal debris.

[0050] As an optional technical solution in this application embodiment, the outer shell includes a housing and an end cap. The housing has an opening at one end along a first direction, and the end cap closes the opening. The housing includes a first wall. Along the thickness direction of the first wall, the support portion is disposed on the side of the first support body facing the first wall, and the abutment area abuts against the first wall. The first support body has a first surface, and the support portion is disposed on the first surface. The end of the first support body away from the end cap along the first direction has a second guide surface. The second guide surface is connected to the first surface, and the second guide surface includes an arc surface and / or an inclined plane.

[0051] In the above technical solution, by setting a second guide surface on the first support body, the second guide surface can play a guiding role during the process of the support being inserted into the shell, thereby facilitating the insertion of the support into the shell.

[0052] As an optional technical solution in this application embodiment, the support member further includes a second support body, the support portion is located between the first support body and the second support body and connects the first support body and the second support body, and the abutment area abuts against the electrode assembly or the first wall through the second support body.

[0053] In the above technical solution, one of the first support and the second support can abut against the electrode assembly, which helps to reduce the stress on the electrode assembly, reduce the risk of damage to the electrode assembly, and extend the life of the battery cell. The other of the first support and the second support can abut against the first wall, which helps to reduce the stress on the first wall and reduce the risk of metal debris generated by scraping against the first wall.

[0054] As an optional technical solution in this application embodiment, the first support body and the support part are integrally formed.

[0055] In the above technical solution, by integrally molding the first support body and the support part, it is beneficial to improve the integrity of the first support body and the support part, improve the connection strength of the first support body and the support part, and enable the support member to play a better constraining role on the electrode assembly in the early stage of battery cell cycle.

[0056] As an optional technical solution in this application embodiment, the support member is made of insulating material.

[0057] In the above technical solution, the support component is made of insulating material, which helps to reduce the risk of short circuit and improve the reliability of the battery cell.

[0058] As an optional technical solution in this application embodiment, the material of the support member includes at least one of polypropylene, polyethylene terephthalate, polyetheretherketone, glass fiber, and polysulfone polymer materials.

[0059] In the above technical solutions, polypropylene, polyethylene terephthalate, polyetheretherketone, glass fiber, and polysulfone polymer materials not only have good insulation properties, but are also not easily corroded by electrolytes. In addition, they also have a certain strength, which can constrain the electrode assembly in the early stage of battery cell cycling and be crushed in the later stage of battery cell cycling, thereby providing expansion space for the electrode assembly.

[0060] As an optional technical solution in this application embodiment, the housing includes two first walls disposed opposite to each other, and the support member is disposed between each first wall and the electrode assembly.

[0061] In the above technical solution, by providing a support between each first wall and the electrode assembly, the two supports can work together to constrain the electrode assembly during the initial stage of battery cell cycling. During the later stages of battery cell cycling, both supports can be crushed, thus providing greater expansion space for the electrode assembly.

[0062] As an optional technical solution in this application embodiment, the battery cell further includes an insulating component, which covers the outer surface of the electrode assembly, and the support component is connected to the insulating component.

[0063] In the above technical solution, by connecting the support to the insulating part, the support can be inserted into the housing along with the electrode assembly when the electrode assembly is inserted into the housing. This helps to maintain the relative position of the support and the electrode assembly, reduce the number of insertions into the housing, and improve production efficiency.

[0064] As an optional technical solution in this application embodiment, the battery cell further includes an expansion member, which is disposed between the electrode assembly and the first wall. The expansion member and the support member are arranged along the thickness direction of the first wall, and the expansion member is configured to absorb electrolyte and expand.

[0065] In the above technical solution, by setting an expansion member between the electrode assembly and the first wall, the expansion member and the support member are arranged along the thickness direction of the first wall. On the one hand, the expansion member can absorb electrolyte and expand, allowing the support member to better abut against the electrode assembly and the first wall. This is beneficial for the support member to provide better constraint on the electrode assembly in the early stage of battery cell cycling. In the later stage of battery cell cycling, the support member is crushed, thus providing expansion space for the electrode assembly. On the other hand, the presence of the expansion member can reduce the dimensional accuracy requirements of the casing, support member, and electrode assembly, making manufacturing easier.

[0066] As an optional technical solution in this application embodiment, the electrode assembly includes a first electrode, a second electrode, and a separator. The first electrode and the second electrode have opposite polarities. The first electrode includes a first electrode segment, and the second electrode includes a second electrode segment. The separator is disposed between the first electrode and the second electrode. The first electrode, the separator, and the second electrode are wound together. The separator has a winding end. The expansion member is a finishing adhesive that connects the winding end and the outermost surface of the separator.

[0067] In the above technical solution, the expansion component serves both as a finishing adhesive and can absorb electrolyte and expand, allowing the support component to better abut against the electrode assembly and the first wall. On the one hand, by utilizing the location of the finishing adhesive, the space occupied by the battery cell is reduced, which is beneficial to improving the energy density of the battery cell. On the other hand, the expansion component can perform multiple functions, which helps to simplify the structure of the battery cell.

[0068] Secondly, embodiments of this application also provide a battery device, which includes the aforementioned battery cell.

[0069] As an optional technical solution in this application embodiment, the battery device includes a housing and a plurality of battery cells arranged along the thickness direction of the first wall. The plurality of battery cells are all housed in the housing, and the outer surface of the first wall of one battery cell is attached to the outer surface of the first wall of another battery cell.

[0070] In the above technical solution, because a support member is provided inside the battery cell, the support member can be crushed during the later stages of battery cell cycling, thereby providing expansion space for the electrode assembly. Therefore, the outer surface of the first wall of one battery cell can be placed against the outer surface of the first wall of another battery cell, reducing the distance between the two battery cells and thus improving the energy density of the battery device.

[0071] Thirdly, embodiments of this application also provide an electrical device, which includes the aforementioned battery cell, and the battery cell is used to provide electrical energy to the electrical device. Attached Figure Description

[0072] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0073] Figure 1 This application provides structural schematic diagrams of vehicles for some embodiments;

[0074] Figure 2 Exploded views of battery devices provided in some embodiments of this application;

[0075] Figure 3 This is a schematic diagram of the structure of a battery cell provided in some embodiments of this application;

[0076] Figure 4 Exploded views of a single battery cell provided in some embodiments of this application;

[0077] Figure 5 This is a schematic diagram of the structure of an electrode assembly provided in some embodiments of this application;

[0078] Figure 6 This is a schematic diagram of the structure of the support member provided in some embodiments of this application;

[0079] Figure 7 A side view schematic diagram of a support member provided in some embodiments of this application;

[0080] Figure 8 for Figure 7 A magnified view of position C in the middle;

[0081] Figure 9 A side view schematic diagram of a support member provided for other embodiments of this application;

[0082] Figure 10 for Figure 9 A magnified view of position D in the middle;

[0083] Figure 11 A side view schematic diagram of a support member provided for some embodiments of this application;

[0084] Figure 12 for Figure 11 A magnified view of position E in the middle;

[0085] Figure 13 A partial structural schematic diagram of the support member provided in some embodiments of this application;

[0086] Figure 14 This application also provides structural schematic diagrams of support members according to some embodiments;

[0087] Figure 15 Partial cross-sectional views of the support provided in some embodiments of this application;

[0088] Figure 16 for Figure 6 A magnified view of position A in the middle;

[0089] Figure 17 for Figure 6 A magnified view of position B in the middle;

[0090] Figure 18 A side view schematic diagram of a support member provided for further embodiments of this application;

[0091] Figure 19 This is a schematic diagram of the structure of an electrode assembly with finishing adhesive attached, provided in some embodiments of this application;

[0092] Figure 20 This is a schematic diagram showing the arrangement of multiple battery cells within a battery device provided in some embodiments of this application.

[0093] Icons: 10-Box body; 11-First box body; 12-Second box body; 20-Battery cell; 21-Outer shell; 211-Shell; 2111-Side wall; 2112-Bottom wall; 212-End cap; 213-First wall; 214-Second wall; 22-Electrode assembly; 221-Main body; 2211-Straight section; 2212-Bent section; 2213-First electrode; 22131-First electrode segment; 2214-Second electrode; 22141-Second electrode segment; 2215-Separator; 22151-Wound end; 2216-Expansion component; 222-Electrode tab; 23-Support component; 231-First support body; 2311-First surface ; 2312-Second weak point; 2313-First groove; 2314-Side side; 2315-Rounded corner surface; 2316-Second guide surface; 2317-Third surface; 232-Support part; 233-Second support body; 2321-Support rib; 23211-Abutting area; 23212-First end; 23123-Second surface; 23214-First guide surface; 23215-First weak point; 23216-Fourth surface; 2322-Arc-shaped part; 23221-Inner arc surface; 23222-Outer arc surface; 24-Insulating component; 25-Electrode terminal; 100-Battery device; 200-Controller; 300-Motor; 1000-Vehicle. Detailed Implementation

[0094] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0095] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0096] In this application, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0097] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0098] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0099] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0100] In this application, "multiple" means two or more (including two).

[0101] In this embodiment of the application, the battery cell can be a secondary battery, which refers to a battery cell that can be recharged to activate the active materials and continue to be used after the battery cell has been discharged.

[0102] Battery cells include, but are not limited to, lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-metal hydride batteries, nickel-cadmium batteries, lead-acid batteries, etc.

[0103] A single battery cell typically includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charging and discharging process of a single battery cell, active ions (such as lithium ions) repeatedly insert and extract between the positive and negative electrodes. The separator, positioned between the positive and negative electrodes, reduces the risk of short circuits while allowing active ions to pass through.

[0104] In some embodiments, the positive electrode may be a positive electrode sheet, which may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0105] As an example, the positive current collector has two surfaces opposite each other in its own thickness direction, and the positive active material is disposed on either or both of the two opposite surfaces of the positive current collector.

[0106] As an example, the positive electrode current collector can be a foil or a composite current collector. For example, as a foil, it can be aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, or titanium, etc. Composite current collectors can include a polymer material base layer and a metal layer. Composite current collectors can be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0107] As an example, the positive electrode active material may include at least one of the following materials: lithium phosphate, lithium transition metal oxide, and their respective modified compounds. However, this application is not limited to these materials, and other conventional materials that can be used as positive electrode active materials in battery cells may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium phosphate may include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), lithium iron phosphate and carbon composites, lithium manganese phosphate (such as LiMnPO4), lithium manganese phosphate and carbon composites, lithium iron manganese phosphate, and lithium iron manganese phosphate and carbon composites. Examples of lithium transition metal oxide may include, but are not limited to, lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, and lithium nickel cobalt manganese oxide (such as LiNi). 1 / 3 Co 1 / 3Mn 1 / 3 O2 (also known as NCM) 333 LiNi 0.5 Co 0.2 Mn 0.3 O2 (also known as NCM) 523 LiNi 0.5 Co 0.25 Mn 0.25 O2 (also known as NCM) 211 LiNi 0.6 Co 0.2 Mn 0.2 O2 (also known as NCM)622 LiNi 0.8 Co 0.1 Mn 0.1 O2 (also known as NCM) 811 ), lithium nickel cobalt aluminum oxide (such as LiNi) 0.85 Co 0.15 Al 0.05 At least one of O2 and its modified compounds.

[0108] In some embodiments, the positive electrode can be a foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloys, etc. When foamed metal is used as the positive electrode, the surface of the foamed metal may or may not contain a positive electrode active material. As an example, lithium source material, potassium metal, or sodium metal can also be filled and / or deposited within the foamed metal, where the lithium source material is lithium metal and / or a lithium-rich material.

[0109] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0110] As an example, the negative electrode current collector can be a foil, a foamed metal, or a composite current collector. For example, as a foil, it can be aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, carbon electrodes, carbon, nickel, or titanium, etc. The foamed metal can be nickel foam, copper foam, aluminum foam, foam alloy, etc. The composite current collector can include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0111] As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector.

[0112] As an example, the negative electrode current collector has two surfaces opposite each other in its own thickness direction, and the negative electrode active material is disposed on either or both of the two opposite surfaces of the negative electrode current collector.

[0113] As an example, the negative electrode active material may be a negative electrode active material known in the art for use in battery cells. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc. Silicon-based materials may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. Tin-based materials may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, this application is not limited to these materials, and other conventional materials that can be used as negative electrode active materials in battery cells may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0114] In some embodiments, the positive current collector can be made of aluminum, and the negative current collector can be made of copper.

[0115] In some embodiments, the separator is a separator membrane. The separator membrane can be any known porous structure separator membrane with good chemical and mechanical stability.

[0116] As an example, the material of the separator may include at least one of glass fiber, nonwoven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator may be a single-layer film or a multi-layer composite film. When the separator is a multi-layer composite film, the materials of each layer may be the same or different. The separator may be a separate component located between the positive and negative electrodes, or it may be attached to the surfaces of the positive and negative electrodes.

[0117] In some embodiments, the battery cell also includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. The electrolyte can be liquid, gel-like, or solid. Liquid electrolytes include electrolyte salts and solvents.

[0118] In some embodiments, the electrolyte salt may include at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalate borate, lithium dioxalate borate, lithium difluorodioxalate phosphate, and lithium tetrafluorooxalate phosphate.

[0119] In some embodiments, the solvent may include at least one selected from ethylene carbonate, propylene carbonate, methyl ethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butyl carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone, and diethyl sulfone. The solvent may also be an ether solvent. Ether solvents may include one or more selected from ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyl tetrahydrofuran, diphenyl ether, and crown ethers.

[0120] Among them, the gel electrolyte includes a polymer as the electrolyte backbone network, combined with an ionic liquid - lithium salt.

[0121] In some implementations, the electrode assembly is a wound structure. The positive and negative electrode sheets are wound into a wound structure.

[0122] In some implementations, the electrode assembly is a stacked structure.

[0123] As an example, multiple positive and negative electrodes can be set, and multiple positive and multiple negative electrodes can be stacked alternately.

[0124] As an example, multiple positive electrode plates can be provided, and negative electrode plates can be folded to form multiple stacked folded segments, with a positive electrode plate sandwiched between adjacent folded segments.

[0125] As an example, both the positive and negative electrode plates are folded to form multiple stacked folded segments.

[0126] As an example, multiple separators can be provided, each positioned between any adjacent positive or negative electrode plates.

[0127] As an example, the separators can be continuously arranged, either by folding or rolling between any adjacent positive or negative electrode plates.

[0128] In some implementations, the electrode assembly may be flat or polygonal in shape.

[0129] In some embodiments, the electrode assembly is provided with tabs that allow current to be drawn from the electrode assembly. The tabs include a positive tab and a negative tab.

[0130] In some embodiments, the battery cell may include a housing. The housing is used to encapsulate components such as electrode assemblies and electrolytes. The housing may be made of steel, aluminum, or a composite metal (such as a copper-aluminum composite housing).

[0131] In some embodiments, the housing can be a sealed structure or a non-sealed structure. As an example, when the housing is a sealed structure, it can protect the electrode assembly and prevent, to some extent, electrolyte leakage. When the housing is a non-sealed structure, it can still protect the electrode assembly, and a sealing bag may be included between the housing and the electrode assembly to encapsulate the electrode assembly and electrolyte. Specifically, the sealing bag can be a bag-shaped insulating component or an aluminum-plastic film.

[0132] As an example, a battery cell can be a prismatic battery cell or a battery cell of other shapes. Prismatic battery cells include prismatic battery cells, blade-shaped battery cells, and multi-prismatic battery cells, such as hexagonal prismatic battery cells.

[0133] The battery device mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells, which are connected in series, parallel, or mixed connections via a busbar.

[0134] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells; as an example, a battery cell assembly can be a battery module, which is formed by arranging multiple battery cells and fixing them together to form an independent module.

[0135] As an example, a battery module can be formed by bundling multiple battery cells together with cable ties.

[0136] In some embodiments, the battery device may be a battery pack, which may include a housing and one or more individual battery cell assemblies housed within the housing.

[0137] As an example, the battery cell assembly can be a battery module, which can be housed in a housing by fixing the battery module in the housing.

[0138] As an example, battery cell assemblies can also be housed in a housing by directly fixing multiple battery cells to the housing.

[0139] As an example, the enclosure may include a first enclosure body and a second enclosure body. The first enclosure body and the second enclosure body are fastened together to form a closed space inside the enclosure to house the individual battery cells. Here, "closed" refers to covering or closing, which can be either sealed or unsealed. The first enclosure body may be a top cover or a bottom plate.

[0140] As an example, the enclosure may include a top cover, a frame, and a bottom plate. The top cover and bottom plate are connected to the frame, creating an enclosed space inside the enclosure to house the individual battery cells.

[0141] As an example, the housing can be part of the vehicle's chassis structure. For instance, the housing's roof can be at least part of the vehicle's floor, or the housing's frame can be at least part of the vehicle's crossbeams and longitudinal beams.

[0142] In some embodiments, the battery device refers to an energy storage device, which includes a housing with a door on at least one side. Energy storage devices include energy storage containers, energy storage cabinets, etc.

[0143] Currently, judging from market trends, battery applications are becoming increasingly widespread. Batteries are not only used in energy storage systems such as hydropower, thermal power, wind power, and solar power plants, but also extensively in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. With the continuous expansion of battery applications, market demand is also constantly increasing.

[0144] The development of battery technology must consider multiple design factors simultaneously, such as energy density, discharge capacity, and charge / discharge rate. Additionally, cycle life must be considered. However, current battery cycle life is relatively short.

[0145] For individual battery cells, a certain gap is usually left between the electrode assembly and the housing to facilitate the installation of the electrode assembly into the casing. However, due to the existence of the gap, in the early stages of battery cell cycling, the electrode assembly lacks restraint, and the thickness of the electrode sheet can easily increase rapidly. This rapid expansion of the electrode assembly leads to a shorter cycle life of the battery cell.

[0146] In view of this, embodiments of this application provide a battery cell, which includes a casing, an electrode assembly, and a support member. The casing has a first wall, and the electrode assembly is housed within the casing. The electrode assembly includes a flat portion, which includes a first electrode segment and a second electrode segment with opposite polarities. The first electrode segment and the second electrode segment are stacked along the thickness direction of the first wall. The support member is supported between the first wall and the electrode assembly along the thickness direction of the first wall. The support member includes a connected first support body and a support portion. Along the thickness direction of the first wall, the support portion is disposed on at least one side of the first support body. The support portion has an abutment area furthest from the first support body, which abuts against the electrode assembly or the first wall, and a gap exists between the abutment area and the first support body.

[0147] By placing a support between the first wall and the electrode assembly, the support can abut against the gap between the electrode assembly and the first wall, filling the gap between them. In the early stages of cell cycling, the support can constrain the electrode assembly, improving electrode wrinkling, inhibiting electrode thickness growth, delaying the expansion process of the electrode assembly, and extending the cell's lifespan. In the later stages of cell cycling, due to the gap between the abutment area of ​​the support and the first support body, the support is easily crushed under the expansion force applied by the electrode assembly, thus providing expansion space for the electrode assembly. Furthermore, the support between the first wall and the electrode assembly provides support to the first wall, making it less prone to deformation under external impact. Moreover, during the formation process, the support can constrain the electrode assembly, helping to reduce gas residue in the electrode assembly during formation and lowering the risk of defects such as purple spots and gas marks on the electrode.

[0148] The technical solutions described in the embodiments of this application are applicable to various electrical devices that use battery cells and battery devices, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, power tools, vehicles, ships and spacecraft, etc. For example, spacecraft include airplanes, rockets, space shuttles and spacecraft.

[0149] For ease of explanation, the following embodiments will use a vehicle as an example of an electrical device.

[0150] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of a vehicle 1000 provided in some embodiments of this application. A battery device 100 is disposed inside the vehicle 1000, and the battery device 100 may be located at the bottom, front, or rear of the vehicle 1000. The battery device 100 can be used to power the vehicle 1000; for example, the battery device 100 can serve as the operating power source for the vehicle 1000.

[0151] The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery device 100 to supply power to the motor 300, for example, for the power needs of the vehicle 1000 during startup, navigation and driving.

[0152] In some embodiments of this application, the battery device 100 can not only serve as the operating power source for the vehicle 1000, but also as the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0153] Please refer to Figure 2 , Figure 2This is an exploded view of a battery device 100 provided in some embodiments of this application. The battery device 100 may include a housing 10 and battery cells 20, the housing 10 being used to house the battery cells 20.

[0154] The housing 10 has an enclosed space inside for accommodating the battery cells 20. The housing 10 can have various structures. In some embodiments, the housing 10 may include a first housing body 11 and a second housing body 12, which are interlocked. The first housing body 11 and the second housing body 12 can have various shapes, such as cuboids or cylinders. The first housing body 11 can be a hollow structure open on one side, and the second housing body 12 can also be a hollow structure open on one side. The open side of the second housing body 12 interlocks with the open side of the first housing body 11, thus forming a housing 10 with an enclosed space. Alternatively, the first housing body 11 can be a hollow structure open on one side, and the second housing body 12 can be a plate-like structure, with the second housing body 12 interlocked with the open side of the first housing body 11, thus forming a housing 10 with an accommodating chamber.

[0155] In the battery device 100, there can be one or more battery cells 20. If there are multiple battery cells 20, they can be connected in series, parallel, or in a mixed configuration. A mixed configuration means that multiple battery cells 20 are connected in both series and parallel. Alternatively, multiple battery cells 20 can be first connected in series, parallel, or in a mixed configuration to form a battery module, and then multiple battery modules can be connected in series, parallel, or in a mixed configuration to form a whole, which is then housed within the housing 10. Another option is that all battery cells 20 can be directly connected in series, parallel, or in a mixed configuration, and then the whole consisting of all battery cells 20 is housed within the housing 10.

[0156] In some embodiments, the battery device 100 may further include a busbar component, through which multiple battery cells 20 can be electrically connected to each other to achieve series, parallel, or mixed connection of the multiple battery cells 20. The busbar component may be a metallic conductor, such as copper, iron, aluminum, stainless steel, aluminum alloy, etc.

[0157] Please refer to Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 and Figure 8 , Figure 3 This is a schematic diagram of the structure of a battery cell 20 provided in some embodiments of this application. Figure 4 An exploded view of a battery cell 20 provided in some embodiments of this application. Figure 5 This is a schematic diagram of the structure of the electrode assembly 22 provided in some embodiments of this application. Figure 6 This is a schematic diagram of the structure of the support member 23 provided in some embodiments of this application. Figure 7This is a side view of the support member 23 provided in some embodiments of this application. Figure 8 for Figure 7 Enlarged view of position C. This application provides a battery cell 20, which includes a housing 21, an electrode assembly 22, and a support member 23. The housing 21 has a first wall 213, and the electrode assembly 22 is housed within the housing 21. The electrode assembly 22 includes a straight portion 2211, which includes a first electrode segment 22131 and a second electrode segment 22141 with opposite polarities. The first electrode segment 22131 and the second electrode segment 22141 are stacked along the thickness direction of the first wall 213. The support member 23 is supported between the first wall 213 and the electrode assembly 22 along the thickness direction of the first wall 213. The support member 23 includes a connected first support body 231 and a support portion 232. Along the thickness direction of the first wall 213, the support portion 232 is disposed on at least one side of the first support body 231. The support portion 232 has an abutment area 23211 that is furthest from the first support body 231. The abutment area 23211 abuts against the electrode assembly 22 or the first wall 213. There is a gap between the abutment area 23211 and the first support body 231.

[0158] Battery cell 20 refers to the smallest unit that makes up battery device 100.

[0159] The housing 21 includes a housing 211 and an end cap 212. The housing 211 has a receiving space with an opening at one end for accommodating the electrode assembly 22. The end cap 212 is connected to the housing 211 and closes the opening.

[0160] End cap 212 refers to a component that covers the opening of housing 211 to isolate the internal environment of battery cell 20 from the external environment. The shape of end cap 212 can be adapted to the shape of housing 211 to fit it. Optionally, end cap 212 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that end cap 212 is less prone to deformation under pressure and impact, enabling battery cell 20 to have higher structural strength and improved reliability. The material of end cap 212 can include, but is not limited to, copper, iron, aluminum, stainless steel, aluminum alloy, and plastic.

[0161] The housing 211 is a component used to cooperate with the end cap 212 to form the internal environment of the battery cell 20. This internal environment can accommodate the electrode assembly 22, electrolyte, and other components. The housing 211 and the end cap 212 can be independent components. An opening can be provided on the housing 211, and the end cap 212 can be used to close the opening to form the internal environment of the battery cell 20. Alternatively, the end cap 212 and the housing 211 can be integrated. Specifically, the end cap 212 and the housing 211 can form a common mating surface before other components are inserted into the housing. When it is necessary to encapsulate the interior of the housing 211, the end cap 212 closes the housing 211. The housing 211 can have various shapes and sizes, such as cuboid, cylindrical, hexagonal prism, etc. Specifically, the shape of the housing 211 can be determined according to the specific shape and size of the electrode assembly 22. The material of the housing 211 can include, but is not limited to, copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0162] In some embodiments, the housing 211 may have an opening at only one end, with one end cap 212 correspondingly provided. In other embodiments, the housing 211 may have openings at both ends, with two end caps 212 correspondingly provided, the two end caps 212 respectively closing the two opposite openings of the housing 211. Figure 3 and Figure 4 In the embodiment shown, the housing 211 has an opening at only one end, and an end cap 212 is provided accordingly.

[0163] Electrode terminals 25 may also be provided on the end cap 212 or the housing 211. These terminals are used for electrical connection to the tabs 222 of the electrode assembly 22 to input or output electrical energy from the battery cell 20. The electrode terminals 25 and tabs 222 can be directly connected, for example, by direct welding. Alternatively, they can be indirectly connected, for example, through a current collector. The current collector can be a metallic conductor, such as copper, iron, aluminum, steel, or aluminum alloy.

[0164] Electrode assembly 22 is the component in the battery cell 20 where electrochemical reactions occur. The housing 211 may contain one or more electrode assemblies 22. The electrode assembly 22 is mainly formed by winding or stacking positive and negative electrode sheets, and typically a separator 2215 is provided between the positive and negative electrode sheets. The portions of the positive and negative electrode sheets containing active material constitute the main body 221 of the electrode assembly 22, while the portions of the positive and negative electrode sheets without active material each constitute a tab 222. The positive and negative tabs may be located together at one end of the main body 221 or separately at both ends of the main body 221. During the charging and discharging process of the battery cell 20, the positive and negative active materials react with the electrolyte.

[0165] The electrode assembly 22 includes a first electrode 2213 and a second electrode 2214, with opposite polarities. One of the first electrode 2213 and the second electrode 2214 is a positive electrode, and the other is a negative electrode. For example, when the first electrode 2213 is a positive electrode, the second electrode 2214 is a negative electrode; when the first electrode 2213 is a negative electrode, the second electrode 2214 is a positive electrode.

[0166] The electrode assembly 22 can be a wound electrode assembly or a stacked electrode assembly. When the electrode assembly 22 is a wound electrode assembly, it includes a straight portion 2211 and a bent portion 2212. The straight portion 2211 is the part of the electrode assembly 22 that extends along a straight trajectory, and the bent portion 2212 is connected to one end of the straight portion 2211. The bent portion 2212 can extend along an arc trajectory. The electrode assembly 22 includes two bent portions 2212, which are respectively connected to the two ends of the straight portion 2211. The first electrode segment 22131 is the portion of the first electrode 2213 located in the straight portion 2211, and the second electrode segment 22141 is the portion of the second electrode 2214 located in the straight portion 2211. When the electrode assembly 22 is a stacked electrode assembly, the entire electrode assembly 22 is a flat portion 2211, the entire first electrode 2213 is a first electrode segment 22131, and the entire second electrode 2214 is a second electrode segment 22141.

[0167] It should be noted that the first pole segment 22131 and the second pole segment 22141 are stacked along the thickness direction of the first wall 213, and a spacer 2215 is also provided between the first pole segment 22131 and the second pole segment 22141.

[0168] The first electrode segment 22131 and the second electrode segment 22141 are stacked along the thickness direction of the first wall 213. In other words, the thickness direction of the first wall 213 is parallel to the stacking direction of the first electrode segment 22131 and the second electrode segment 22141. Please refer to... Figure 3 and Figure 4 In the embodiment shown in the figure, the first wall 213 is a side wall 2111 of the shell 211. Specifically, the first wall 213 is the side wall 2111 with the largest outer surface area of ​​the shell 211, commonly known as the large surface. The thickness direction of the first wall 213 is the X direction shown in the figure.

[0169] The support member 23 is a support structure that supports the first wall 213 and the electrode assembly 22 along the thickness direction of the first wall 213. The support member 23 is configured to be crushed when the expansion force applied by the electrode assembly 22 reaches a threshold, so as to provide expansion space for the electrode assembly 22. The crushing of the support member 23 refers to the deformation or cracking that occurs when the pressure on the support member 23 exceeds its bearing capacity.

[0170] The first support 231 is the main structure of the support member 23, and can serve as the mounting base for the support part 232. In some embodiments, the first support 231 can be a plate-like structure, and can abut against the electrode assembly 22 or the first wall 213. When the first support 231 abuts against the electrode assembly 22, it can reduce the stress on the electrode assembly 22 and lower the risk of damage to the electrode assembly 22. When the first support 231 abuts against the first wall 213, it can reduce the stress on the first wall 213 and lower the risk of metal fragments generated by scraping against the first wall 213.

[0171] The support portion 232 can be connected to the side of the first support body 231 facing the first wall 213 along the thickness direction of the first wall 213, or the support portion 232 can be connected to the side of the first support body 231 facing the electrode assembly 22 along the thickness direction of the first wall 213. Of course, the support portion 232 can be provided on both sides of the first support body 231 along the thickness direction of the first wall 213.

[0172] The support portion 232 is configured to be crushed when the expansion force applied by the electrode assembly 22 reaches a threshold, so as to provide expansion space for the electrode assembly 22.

[0173] The abutment area 23211 is the portion of the support portion 232 furthest from the first support body 231 along the thickness direction of the first wall 213. "The abutment area 23211 abuts against the electrode assembly 22 or the first wall 213" means that the abutment area 23211 can directly or indirectly abut against the electrode assembly 22 or the first wall 213. For example, the abutment area 23211 can directly abut against the electrode assembly 22, or it can indirectly abut against the electrode assembly 22 through other intermediate components besides the first support body 231. Similarly, the abutment area 23211 can directly abut against the first wall 213, or it can indirectly abut against the first wall 213 through other intermediate components besides the first support body 231.

[0174] Along the thickness direction of the first wall 213, there is a gap between the abutment area 23211 and the first support body 231, so that the support part 232 is easily crushed when the expansion force applied by the electrode assembly 22 reaches the threshold, so as to provide expansion space for the electrode assembly 22.

[0175] By providing a support member 23 between the first wall 213 and the electrode assembly 22, the support member 23 can abut against the gap between the electrode assembly 22 and the first wall 213, thus filling the gap between them. In the early stages of battery cell 20 cycling, the support member 23 can constrain the electrode assembly 22, improving electrode wrinkling, suppressing electrode thickness growth, delaying the expansion process of the electrode assembly 22, and extending the lifespan of the battery cell 20. In the later stages of battery cell 20 cycling, due to the gap between the abutment area 23211 of the support portion 232 and the first support body 231, the support portion 232 is easily crushed under the expansion force applied by the electrode assembly 22, thereby providing expansion space for the electrode assembly 22. Furthermore, because the support member 23 is provided between the first wall 213 and the electrode assembly 22, it can support the first wall 213, making it less prone to deformation under external impact. Furthermore, during the formation process, the support member 23 can constrain the electrode assembly 22, which helps to reduce the gas residue in the electrode assembly 22 during the formation process and reduce the risk of defects such as purple spots and gas marks on the electrode sheet.

[0176] Please refer to Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 and Figure 8 In some embodiments, along the thickness direction of the first wall 213, the support portion 232 is disposed on the side of the first support body 231 facing the first wall 213, and the abutment area 23211 abuts against the first wall 213.

[0177] Please refer to Figure 4 , Figure 6 , Figure 7 and Figure 8 In the embodiment shown in the figure, the support portion 232 is only provided on the side of the first support body 231 facing the first wall 213 along the thickness direction of the first wall 213. In this way, the first support body 231 can abut against the electrode assembly 22, which can reduce the stress on the electrode assembly 22 and reduce the risk of damage to the electrode assembly 22.

[0178] The abutment area 23211 can directly abut against the first wall 213, or the abutment area 23211 can indirectly abut against the first wall 213 through other intermediate components other than the first support body 231.

[0179] The support portion 232 is disposed on the side of the first support body 231 facing the first wall 213 along the thickness direction of the first wall 213, and the abutment area 23211 abuts against the first wall 213, so that the first support body 231 can abut against the electrode assembly 22. Compared with the support portion 232, the first support body 231 can better support the electrode assembly 22, which is beneficial to reduce the stress on the electrode assembly 22, reduce the risk of damage to the electrode assembly 22, and extend the life of the battery cell 20.

[0180] Please refer to Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 and Figure 8 In some embodiments, the projection of the straight portion 2211 along the thickness direction of the first wall 213 is completely located within the first support 231.

[0181] The projection of the straight portion 2211 along the thickness direction of the first wall 213 is completely located within the first support 231. That is, when viewed along the thickness direction of the first wall 213, the first support 231 can completely cover the straight portion 2211.

[0182] The projection of the straight portion 2211 along the thickness direction of the first wall 213 is completely within the first support 231, so that the first support 231 can better support the electrode assembly 22, reduce the stress on the electrode assembly 22, reduce the risk of damage to the electrode assembly 22, and extend the life of the battery cell 20.

[0183] Please refer to Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 and Figure 8 In some embodiments, the support portion 232 includes at least one support rib 2321, which is inclinedly disposed on the first support body 231.

[0184] The support portion 232 may include one support rib 2321, two support ribs 2321, three support ribs 2321, four support ribs 2321, or more support ribs 2321. Multiple support ribs 2321 may be spaced apart along a first direction on the first support body 231, and the first direction may be perpendicular to the thickness direction of the first wall 213. Please refer to... Figure 6 , Figure 7 , Figure 8 The first direction is the Y direction shown in the figure.

[0185] Along the thickness direction of the first wall 213, the first support 231 has a first surface 2311, and the support rib 2321 is connected to the first surface 2311.

[0186] The support rib 2321 can be a plate-like structure or a strip-like structure. The support rib 2321 has a first end 23212 and a second end that are arranged opposite to each other, wherein the first end 23212 is connected to the first support body 231, and the second end forms the aforementioned abutment area 23211.

[0187] The extension direction of the support rib 2321 is the direction from the first end 23212 to the second end. "The support rib 2321 is inclinedly arranged on the first support body 231" means that the angle between the extension direction of the support rib 2321 and the first surface 2311 is an acute angle.

[0188] The support portion 232 includes at least one support rib 2321 inclinedly disposed on the first support body 231. In the early stages of battery cell 20 cycling, the support rib 2321 experiences less stress and can maintain its original shape, allowing the support member 23 to effectively constrain the electrode assembly 22, suppressing electrode thickness growth, delaying the expansion process of the electrode assembly 22, and extending the lifespan of the battery cell 20. In the later stages of battery cell 20 cycling, the support rib 2321 experiences greater expansion force from the electrode assembly 22, making it easier to crush and thus providing expansion space for the electrode assembly 22.

[0189] Please refer to Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 and Figure 8 In some embodiments, along the thickness direction of the first wall 213, the first support 231 has a first surface 2311, and a support rib 2321 is connected to the first surface 2311. The angle between the extending direction of the support rib 2321 and the first surface 2311 is α, satisfying: 20°≤α≤70°.

[0190] The support rib 2321 has a first end 23212 and a second end disposed opposite to each other, wherein the first end 23212 is connected to the first support body 231, and the second end forms the aforementioned abutment area 23211. The extension direction of the support rib 2321 is the direction from the first end 23212 to the second end.

[0191] α represents the angle between the extension direction of the support rib 2321 and the first surface 2311. When the surface of the support rib 2321 facing the first support body 231 is a plane, the angle between the surface of the support rib 2321 facing the first support body 231 and the first surface 2311 can be measured as α.

[0192] α can take values ​​of: 20°, 25°, 30°, 35°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, etc.

[0193] When α ≤ 70°, the angle between the extension direction of the support rib 2321 and the first surface 2311 is small, which facilitates the crushing of the support rib 2321 in the later stages of battery cell 20 cycling, thereby providing expansion space for the electrode assembly 22. When α ≥ 20°, the angle between the extension direction of the support rib 2321 and the first surface 2311 is not too small. On the one hand, this allows the support rib 2321 to withstand a certain amount of pressure, thus facilitating the better constraint of the support member 23 on the electrode assembly 22 in the early stages of battery cell 20 cycling. On the other hand, when the length of the support rib 2321 along its extension direction is the same, when α ≥ 20°, the space occupied by the support rib 2321 along the thickness direction of the first wall 213 is larger, which can better fill the gap between the electrode assembly 22 and the first wall 213, thus facilitating the better constraint of the support member 23 on the electrode assembly 22 in the early stages of battery cell 20 cycling, and providing a larger expansion space after the support rib 2321 is crushed. Therefore, when 20°≤α≤70°, it is beneficial for the support member 23 to play a better constraining role on the electrode assembly 22 in the early stage of the battery cell 20 cycle, and it is also beneficial to provide a larger expansion space after the support rib 2321 is crushed.

[0194] Optionally, 30°≤α≤60°.

[0195] α can take values ​​of: 30°, 32°, 35°, 38°, 40°, 42°, 45°, 48°, 50°, 52°, 55°, 58°, 60°, etc.

[0196] When α ≤ 60°, the angle between the extension direction of the support rib 2321 and the first surface 2311 is smaller, making it easier for the support rib 2321 to be crushed in the later stages of battery cell 20 cycling, thus providing expansion space for the electrode assembly 22. When α ≥ 30°, the angle between the extension direction of the support rib 2321 and the first surface 2311 is not too small. On the one hand, this allows the support rib 2321 to withstand a certain amount of pressure, thus facilitating the support member 23 to provide better constraint for the electrode assembly 22 in the early stages of battery cell 20 cycling. On the other hand, when the length of the support rib 2321 along its extension direction is the same, when α ≥ 30°, the space occupied by the support rib 2321 along the thickness direction of the first wall 213 is larger, which can better fill the gap between the electrode assembly 22 and the first wall 213, thus facilitating the support member 23 to provide better constraint for the electrode assembly 22 in the early stages of battery cell 20 cycling, and providing greater expansion space after the support rib 2321 is crushed. Therefore, when 30°≤α≤60°, it is more conducive to the support member 23 to play a better constraining role on the electrode assembly 22 in the early stage of the battery cell 20 cycle, and it is also more conducive to providing a larger expansion space after the support rib 2321 is crushed.

[0197] Please refer to Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 and Figure 8 In some embodiments, the thickness of the first support 231 is H1, and the thickness of the support rib 2321 is H2, satisfying: 0.5≤H2 / H1≤3.

[0198] H1 represents the thickness of the first support 231. Along the thickness direction of the first wall 213, the first support 231 includes a first surface 2311 and a third surface 2317 disposed opposite to each other, wherein the support portion 232 is connected to the first surface 2311. During measurement, the distance between the first surface 2311 and the third surface 2317 can be measured as H1.

[0199] H2 represents the thickness of the support rib 2321. Multiple measurements can be taken, and the average value can be used as H2.

[0200] H2 / H1 represents the ratio of the thickness of the support rib 2321 to the thickness of the first support body 231.

[0201] H2 / H1 can take values ​​of: 0.5, 0.8, 1, 1.2, 1.5, 1.8, 2, 2.2, 2.5, 2.8, 3, etc.

[0202] When H2 / H1 ≥ 0.5, the ratio of the thickness of the support rib 2321 to the thickness of the first support body 231 is relatively large, resulting in a thicker support rib 2321. This allows the support rib 2321 to withstand a certain amount of pressure, thus facilitating the support member 23 to provide better constraint on the electrode assembly 22 during the initial cycle of the battery cell 20. When H2 / H1 ≤ 3, the ratio of the thickness of the support rib 2321 to the thickness of the first support body 231 is not too large, preventing the support rib 2321 from becoming too thick. This facilitates the crushing of the support rib 2321 during the later stages of the battery cell 20 cycle, thereby providing expansion space for the electrode assembly 22. Therefore, when 0.5 ≤ H2 / H1 ≤ 3, it is beneficial for the support member 23 to provide better constraint on the electrode assembly 22 during the initial cycle of the battery cell 20, and also beneficial for providing a larger expansion space after the support rib 2321 is crushed.

[0203] Optionally, 1.5 ≤ H2 / H1 ≤ 2.5.

[0204] H2 / H1 can be 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.1, 2.2, 2.3, 2.4, 2.5, etc.

[0205] When H2 / H1 ≥ 1.5, the ratio of the thickness of the support rib 2321 to the thickness of the first support body 231 is larger, making the support rib 2321 thicker. This allows the support rib 2321 to withstand a certain amount of pressure, thus facilitating the support member 23 to provide better constraint on the electrode assembly 22 during the initial cycle of the battery cell 20. Furthermore, since the support rib 2321 is the main stress-bearing part of the support member 23, the first support body 231 is less prone to damage compared to the support rib 2321. Making the first support body 231 thinner can reduce the space occupied by the first support body 231 inside the battery cell 20, which is beneficial to improving the energy density of the battery cell 20, and can also provide greater expansion space after the support member 23 is crushed. When H2 / H1≤2.5, the ratio of the thickness of the support rib 2321 to the thickness of the first support 231 will not be too large, ensuring that the support rib 2321 is not too thick. This facilitates the crushing of the support rib 2321 in the later stages of battery cell 20 cycling, thus providing expansion space for the electrode assembly 22. Therefore, when 1.5≤H2 / H1≤2.5, it is beneficial for the support member 23 to provide better constraint on the electrode assembly 22 in the early stages of battery cell 20 cycling, and also for providing a larger expansion space after the support rib 2321 is crushed.

[0206] Please refer to Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 and Figure 8 In some embodiments, the thickness of the first support 231 is H1, which satisfies: 0.1mm≤H1≤0.5mm.

[0207] H1 can be 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm, 0.5mm, etc.

[0208] When H1 ≥ 0.1 mm, the thickness of the first support 231 is relatively large, giving it higher strength and reducing the risk of damage. This allows the first support 231 to better support the electrode assembly 22, reducing stress on the electrode assembly 22 and lowering the risk of damage. When H1 ≤ 0.5 mm, the thickness of the first support 231 is not excessive, reducing its encroachment on the internal space of the battery cell 20, improving the energy density of the battery cell 20, and providing greater expansion space after the support 23 is crushed. Therefore, when 0.1 mm ≤ H1 ≤ 0.5 mm, it not only reduces the risk of damage to the first support 231 and the electrode assembly 22, but also improves the energy density of the battery cell 20 and provides greater expansion space after the support 23 is crushed.

[0209] Optionally, 0.2mm ≤ H1 ≤ 0.4mm.

[0210] H1 can be 0.2mm, 0.22mm, 0.25mm, 0.28mm, 0.3mm, 0.32mm, 0.35mm, 0.38mm, 0.4mm, etc.

[0211] When H1 ≥ 0.2 mm, the thickness of the first support 231 is greater, resulting in higher strength and reducing the risk of damage. This allows the first support 231 to better support the electrode assembly 22, reducing stress on the electrode assembly 22 and lowering the risk of damage. When H1 ≤ 0.4 mm, the thickness of the first support 231 is not excessive, reducing its encroachment on the internal space of the battery cell 20, improving the energy density of the battery cell 20, and providing greater expansion space after the support 23 is crushed. Therefore, when 0.2 mm ≤ H1 ≤ 0.4 mm, it is more conducive to reducing the risk of damage to the first support 231 and the electrode assembly 22, improving the energy density of the battery cell 20, and providing greater expansion space after the support 23 is crushed.

[0212] Please refer to Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 and Figure 8 In some embodiments, the thickness of the support rib 2321 is H2, which satisfies: 0.15mm≤H2≤1.5mm.

[0213] H2 can be in the following sizes: 0.15mm, 0.3mm, 0.45mm, 0.6mm, 0.75mm, 0.9mm, 1.05mm, 1.2mm, 1.35mm, 1.5mm, etc.

[0214] When H2 ≥ 0.15 mm, the support rib 2321 is relatively thick, allowing it to withstand a certain amount of pressure. This facilitates the support member 23's effective constraint on the electrode assembly 22 during the initial cycle of the battery cell 20. When H2 ≤ 1.5 mm, the support rib 2321 is not excessively thick, allowing it to be crushed during the later cycle of the battery cell 20, thus providing expansion space for the electrode assembly 22. Therefore, when 0.15 mm ≤ H2 ≤ 1.5 mm, the support member 23 effectively constrains the electrode assembly 22 during the initial cycle of the battery cell 20, while also providing ample expansion space after the support rib 2321 is crushed.

[0215] Optionally, 0.3mm ≤ H2 ≤ 0.8mm.

[0216] H2 can be in the following sizes: 0.3mm, 0.35mm, 0.4mm, 0.45mm, 0.5mm, 0.55mm, 0.6mm, 0.65mm, 0.7mm, 0.75mm, 0.8mm, etc.

[0217] When H2 ≥ 0.3 mm, the support rib 2321 is thicker, allowing it to withstand certain pressure. This facilitates better constraint of the support member 23 on the electrode assembly 22 during the initial cycle of the battery cell 20. When H2 ≤ 0.8 mm, the support rib 2321 is not too thick, allowing it to be crushed during the later cycle of the battery cell 20, thus providing expansion space for the electrode assembly 22. Therefore, when 0.3 mm ≤ H2 ≤ 0.8 mm, it is more conducive to the support member 23 providing better constraint on the electrode assembly 22 during the initial cycle of the battery cell 20, and also provides greater expansion space after the support rib 2321 is crushed.

[0218] Please refer to Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 and Figure 8In some embodiments, along the thickness direction of the first wall 213, a support rib 2321 is disposed on the side of the first support body 231 facing the first wall 213, and an abutment area 23211 abuts against the first wall 213. Along the thickness direction of the support rib 2321, the support rib 2321 includes a second surface 23123, which faces the first wall 213. The abutment area 23211 has a first guide surface 23214, which is connected to the second surface 23123. The first guide surface 23214 includes an arc surface and / or an inclined plane.

[0219] Please refer to Figure 8 The thickness direction of the support rib 2321 is the Q direction shown in the figure.

[0220] The second surface 23123 is the surface of the support rib 2321 facing the first wall 213 along its thickness direction.

[0221] The abutment area 23211 has a first guide surface 23214, which can directly or indirectly abut against the first wall 213. Optionally, the first guide surface 23214 directly abuts against the first wall 213.

[0222] The first guide surface 23214 is connected to the second surface 23123. The first guide surface 23214 can be a rounded transition surface disposed in the abutment area 23211. In this case, the first guide surface 23214 is an arc surface. The first guide surface 23214 can also be an angled transition surface disposed in the abutment area 23211. In this case, the first guide surface 23214 is an inclined plane.

[0223] Please refer to Figure 8 In the embodiment shown in the figure, the support rib 2321 includes a second surface 23123 and a fourth surface 23216 disposed opposite to each other along its thickness direction, and the second guide surface 2316 connects the second surface 23123 and the fourth surface 23216.

[0224] In other embodiments, the support rib 2321 includes a second surface 23123 and a fourth surface 23216 disposed opposite to each other along its thickness direction, the abutment area 23211 includes a first end face connected to the fourth surface 23216, and a first guide surface 23214 connected to the first end face and the second surface 23123.

[0225] By providing a first guiding surface 23214, during the insertion of the support member 23 into the housing, the first guiding surface 23214 can abut against the inner surface of the first wall 213, reducing the stress of the support rib 2321 on the first wall 213 and lowering the risk of the support rib 2321 scraping against the first wall 213 and generating metal debris. During the use of the battery cell 20, the first guiding surface 23214 can abut against the inner surface of the first wall 213, reducing the stress of the support rib 2321 on the first wall 213 and lowering the risk of the support rib 2321 scraping against the first wall 213 and generating metal debris.

[0226] Please refer to Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 and Figure 8 In some embodiments, the outer casing 21 includes a housing 211 and an end cap 212. The housing 211 has an opening at one end along a first direction, and the end cap 212 closes the opening. The housing 211 includes a first wall 213. Along the thickness direction of the first wall 213, a support rib 2321 is disposed on the side of the first support body 231 facing the first wall 213, and an abutment area 23211 abuts against the first wall 213. The support rib 2321 includes a first end 23212 disposed opposite to the abutment area 23211, and the first end 23212 is connected to the first support body 231. Along the first direction, the abutment area 23211 is closer to the end cap 212 than the first end 23212. The first direction is perpendicular to the thickness direction of the first wall 213.

[0227] Please refer to Figure 4 , Figure 6 , Figure 7 and Figure 8 The first direction is the Y direction shown in the figure.

[0228] The support rib 2321 includes a first end 23212 and an abutment area 23211 disposed opposite each other along its extending direction. The first end 23212 is connected to the first support body 231, and the abutment area 23211 is located away from the first support body 231. Along the first direction, the distance between the abutment area 23211 and the end cap 212 is less than the distance between the first end 23212 and the end cap 212. In other words, the support rib 2321 is inclined from the first support body 231 toward the end cap 212.

[0229] The abutment area 23211 is closer to the end cap 212 than the first end 23212. That is, the support rib 2321 is inclined from the first support body 231 toward the end cap 212. In this way, when the support member 23 is inserted into the shell, the support rib 2321 can guide it, thus facilitating the insertion of the support member 23 into the shell.

[0230] Please refer to Figure 9 and Figure 10 , Figure 9 This is a side view of the support member 23 provided in some other embodiments of this application. Figure 10 for Figure 9 Enlarged view of position D. In some embodiments, the housing 21 includes a second wall 214, which is disposed opposite to the electrode assembly 22 along a first direction perpendicular to the thickness direction of the first wall 213. The support portion 232 includes a plurality of support ribs 2321, each support rib 2321 including a first end 23212 disposed opposite to an abutment area 23211, the first end 23212 being connected to the first support body 231. The abutment area 23211 of one support rib 2321 is closer to the second wall 214 than the first end 23212, and the abutment area 23211 of another support rib 2321 is farther away from the second wall 214 than the first end 23212.

[0231] The second wall 214 is a wall portion of the outer casing 21 disposed opposite to the electrode assembly 22 along the first direction. The second wall 214 can be an end cap 212, or it can be a bottom wall 2112 of the casing 211 disposed opposite to the end cap 212. Please refer to... Figure 3 and Figure 4 In the embodiment shown in the figure, the second wall 214 is the bottom wall 2112 of the shell 211.

[0232] A support portion 232 may include two, three, four, or more support ribs 2321. Each support rib 2321 includes a first end 23212 and an abutment area 23211 disposed opposite each other along its extension direction, wherein the first end 23212 is connected to the first support body 231, and the abutment area 23211 is away from the first support body 231. In a support portion 232, at least one support rib 2321 has an abutment area 23211 closer to the second wall 214 than its first end 23212, and at least one support rib 2321 has an abutment area 23211 farther from the second wall 214 than its first end 23212. That is, at least one support rib 2321 is inclined from the first support body 231 toward the direction closer to the second wall 214, and at least one support rib 2321 is inclined from the first support body 231 toward the direction away from the second wall 214.

[0233] Please refer to Figure 9 and Figure 10 In the embodiment shown in the figure, a support portion 232 includes two support ribs 2321, wherein the abutment area 23211 of one support rib 2321 is closer to the second wall 214 than its first end 23212, and the abutment area 23211 of the other support rib 2321 is farther away from the second wall 214 than its first end 23212.

[0234] The support portion 232 includes multiple support ribs 2321. One support rib 2321 is inclined from the first support body 231 toward the direction closer to the second wall 214, and another support rib 2321 is inclined from the first support body 231 toward the direction away from the second wall 214. In this way, the support member 23 can withstand greater pressure, thereby facilitating the support member 23 to provide better constraint on the electrode assembly 22 in the early stages of battery cell 20 cycling. The support member 23 can still be crushed in the later stages of battery cell 20 cycling, thereby providing expansion space for the electrode assembly 22.

[0235] Please refer to Figure 11 and Figure 12 , Figure 11 This is a side view of the support member 23 provided in some embodiments of this application. Figure 12 for Figure 11 Enlarged view of position E in the middle. In some other embodiments, the support portion 232 includes an arcuate portion 2322, which is connected to the first support body 231.

[0236] The arc-shaped portion 2322 is an arc-shaped structure extending along an arc trajectory. For example, the arc-shaped portion 2322 may be arched. In some embodiments, the arc-shaped portion 2322 is connected to the first support 231 at only one end, and the other end is a free end. In other embodiments, both ends of the arc-shaped portion 2322 are connected to the first support 231.

[0237] The support portion 232 includes an arc-shaped portion 2322, which can withstand greater pressure, thereby facilitating the support member 23 to provide better constraint on the electrode assembly 22 during the initial cycle of the battery cell 20. The support member 23 can still be crushed in the later cycle of the battery cell 20, thus providing expansion space for the electrode assembly 22.

[0238] Please refer to Figure 11 and Figure 12 In some embodiments, along the thickness direction of the first wall 213, the arcuate portion 2322 includes an inner arcuate surface 23221 and an outer arcuate surface 23222 disposed opposite to each other. The inner arcuate surface 23221 faces the first support body 231, and a portion of the outer arcuate surface 23222 abuts against the electrode assembly 22 or the first wall 213. Along the extending direction of the arcuate portion 2322, at least one end of the arcuate portion 2322 is connected to the first support body 231.

[0239] Please refer to Figure 11 and Figure 12In the embodiment shown in the figure, the arc-shaped portion 2322 is arched. Along the thickness direction of the first wall 213, the arc-shaped portion 2322 includes an inner arc surface 23221 and an outer arc surface 23222 disposed opposite to each other. The inner arc surface 23221 faces the first support 231, and the outer arc surface 23222 is disposed on the side of the inner arc surface 23221 away from the first support 231. A portion of the outer arc surface 23222 is the outer surface of the abutment area 23211, allowing a portion of the outer arc surface 23222 to directly or indirectly abut against the electrode assembly 22 or the first wall 213.

[0240] In some embodiments, the arcuate portion 2322 is connected to the first support 231 at only one end, and the other end is a free end. In other embodiments, both ends of the arcuate portion 2322 are connected to the first support 231.

[0241] The arc-shaped portion 2322 is roughly arched. When one end of the arc-shaped portion 2322 is connected to the first support 231 and the other end is free, the support member 23 can still constrain the electrode assembly 22 in the early stages of battery cell 20 cycling. The support member 23 is more easily crushed in the later stages of battery cell 20 cycling, thus providing expansion space for the electrode assembly 22. When both ends of the arc-shaped portion 2322 are connected to the first support 231, the arc-shaped portion 2322 can withstand greater pressure, thus facilitating better constraint of the electrode assembly 22 by the support member 23 in the early stages of battery cell 20 cycling. The support member 23 can still be crushed in the later stages of battery cell 20 cycling, thus providing expansion space for the electrode assembly 22.

[0242] In some embodiments, both ends of the arcuate portion 2322 are connected to the first support 231 along the extending direction of the arcuate portion 2322.

[0243] Both ends of the arc-shaped portion 2322 along its extension direction are connected to the first support 231. The arc-shaped portion 2322 can withstand greater pressure, thereby facilitating the support member 23 to better constrain the electrode assembly 22 in the early stages of battery cell 20 cycling. The support member 23 can still be crushed in the later stages of battery cell 20 cycling, thereby providing expansion space for the electrode assembly 22.

[0244] Please refer to Figure 13 , Figure 13 This is a partial structural schematic diagram of the support member 23 provided in some embodiments of the present application. In some embodiments, the support 232 has a first weak portion 23215, which is configured to be destroyed when the expansion force applied by the electrode assembly 22 reaches a threshold.

[0245] The strength of the support portion 232 at the first weak portion 23215 can be lower than the strength of other portions of the support portion 232. In this way, when the support portion 232 is subjected to an expansion force applied by the electrode assembly 22 and reaches a threshold, the first weak portion 23215 can be destroyed, thereby facilitating the crushing of the support portion 232 and providing expansion space for the electrode assembly 22.

[0246] In some embodiments, the cross-sectional area of ​​the first weak portion 23215 is smaller than the cross-sectional area of ​​other locations of the support portion 232, so that the strength of the support portion 232 at the location of the first weak portion 23215 is lower than the strength at other locations of the support portion 232.

[0247] By providing a first weak portion 23215 on the support portion 232, the first weak portion 23215 can be destroyed when the expansion force applied by the electrode assembly 22 reaches a threshold, thereby facilitating the crushing of the support portion 232 in the later stages of the battery cell 20 cycle, thereby providing expansion space for the electrode assembly 22.

[0248] Please refer to Figure 14 , Figure 14 The diagram below shows the structure of the support member 23 provided in some embodiments of this application. In some embodiments, the support member 23 includes a plurality of support portions 232, which are arranged along a first direction perpendicular to the thickness direction of the first wall 213.

[0249] The support member 23 may include two support portions 232, three support portions 232, four support portions 232, or more support portions 232. Along the first direction, the multiple support portions 232 are spaced apart.

[0250] By providing multiple support portions 232, the support portions 232 can cooperate to support the first support body 231, making the first support body 231 more stable. In addition, the multiple support portions 232 can disperse the expansion force applied by the electrode assembly 22, so that the support member 23 can better constrain the electrode assembly 22 in the early stage of battery cell 20 cycling. The support member 23 can still be crushed in the later stage of battery cell 20 cycling, thereby providing expansion space for the electrode assembly 22.

[0251] Please refer to Figure 14 and Figure 15 , Figure 15 The present application also provides a partial cross-sectional view of the support member 23 provided in some embodiments. In some embodiments, the first support 231 has a second weak portion 2312, which is disposed between two adjacent support portions 232 along a first direction.

[0252] The strength of the first support 231 at the second weak part 2312 can be lower than the strength at other parts of the first support 231. In this way, in the later stage of the battery cell 20 cycle, the first support 231 is more likely to deform under the expansion force of the electrode assembly 22, thereby adapting to the deformation of the surface of the electrode assembly 22 facing the first wall 213 to a certain extent, reducing the stress on the electrode assembly 22 and reducing the risk of damage to the electrode assembly 22.

[0253] In some embodiments, the thickness of the second weak portion 2312 is less than the thickness of other locations of the first support 231, such that the strength of the first support 231 at the location of the second weak portion 2312 is lower than the strength at other locations of the first support 231.

[0254] There may be one or more second weak parts 2312, and the second weak parts 2312 are disposed between two adjacent support parts 232 along the first direction.

[0255] During the later stages of battery cell 20 cycling, the electrode assembly 22 expands, causing the surface of the electrode assembly 22 facing the first wall 213 to gradually bend into an arc shape. By providing a second weak point 2312 on the first support 231, the first support 231 can deform during the later stages of battery cell 20 cycling, thereby adapting to the deformation of the surface of the electrode assembly 22 facing the first wall 213 to a certain extent, reducing the stress on the electrode assembly 22, and lowering the risk of damage to the electrode assembly 22.

[0256] Please refer to Figure 14 and Figure 15 In some embodiments, a first groove 2313 is provided on the first support 231, and the bottom wall of the first groove 2313 includes a second weak part 2312.

[0257] Along the thickness direction of the first wall 213, the first support 231 has a first surface 2311 and a third surface 2317 disposed opposite to each other, wherein a support portion 232 is provided on the first surface 2311. The first groove 2313 may be disposed on the first surface 2311 or on the third surface 2317. Please refer to... Figure 14 and Figure 15 In the embodiment shown in the figure, the first groove 2313 is disposed on the first surface 2311.

[0258] The first groove 2313 can be formed in various ways, such as stamping or cold heading. The first groove 2313 can be a straight groove or an arc groove.

[0259] The second weak part 2312 is formed by setting a first groove 2313 on the first support 231, which is simple, convenient and easy to manufacture.

[0260] Please refer to Figure 14 and Figure 15 In some embodiments, the first groove 2313 extends along a second direction, and the first direction, the second direction and the thickness direction of the first wall 213 are perpendicular to each other.

[0261] The first groove 2313 can be a straight groove, and the first groove 2313 extends along the second direction. Please refer to... Figure 14 The second direction is the Z direction shown in the figure. The first direction, the second direction and the thickness direction of the first wall 213 are perpendicular to each other.

[0262] The first groove 2313 extends along the second direction, and correspondingly, the second weak part 2312 also extends along the second direction, which makes it easier for the first support 231 to deform in the later stage of the battery cell 20 cycle, thereby adapting to the deformation of the surface of the electrode assembly 22 facing the first wall 213 to a certain extent.

[0263] Please refer to Figure 14 and Figure 15 In some embodiments, along the thickness direction of the first wall 213, a support portion 232 is disposed on the side of the first support body 231 facing the first wall 213, and an abutment area 23211 abuts against the first wall 213. The first groove 2313 and the support portion 232 are disposed on the surface of the first support body 231 facing the first wall 213.

[0264] Along the thickness direction of the first wall 213, the first support 231 has a first surface 2311 and a third surface 2317 disposed opposite to each other. A support portion 232 is disposed on the first surface 2311, and a first groove 2313 is recessed from the first surface 2311 in a direction pointing from the first surface 2311 to the second surface 23123. In other words, the first groove 2313 and the support portion 232 are disposed on the same surface of the first support 231.

[0265] Both the first groove 2313 and the support portion 232 are disposed on the surface of the first support body 231 facing the first wall 213, which helps to keep the surface of the first support body 231 away from the first wall 213 flat, thereby facilitating the first support body 231 to better support the electrode assembly 22, reducing the stress on the electrode assembly 22, and reducing the risk of damage to the electrode assembly 22.

[0266] Please refer to Figure 6 and Figure 16 , Figure 16 for Figure 6Enlarged view of position A. In some embodiments, the first support 231 includes a first surface 2311 and a plurality of side surfaces 2314, a support portion 232 is disposed on the first surface 2311, and the plurality of side surfaces 2314 surround the first surface 2311. At least one set of adjacent pairs of side surfaces 2314 are connected by a rounded corner surface 2315.

[0267] Please refer to Figure 6 and Figure 16 In the embodiment shown in the figure, the first support 231 is a rectangular plate structure. The first support 231 includes a first surface 2311 and four side surfaces 2314, which surround the first surface 2311. Each pair of adjacent side surfaces 2314 forms a group, so the first support 231 includes four groups of adjacent side surfaces 2314. In the four groups of adjacent side surfaces 2314, at least one group of adjacent side surfaces 2314 is connected by a rounded corner surface 2315, that is, at least one corner of the rectangular plate structure is rounded.

[0268] By connecting at least one set of two adjacent sides 2314 through a rounded corner 2315, it is beneficial to reduce the risk of the first support 231 scraping against the first wall 213 and generating metal debris.

[0269] Please refer to Figure 6 and Figure 17 , Figure 17 for Figure 6 Enlarged view of position B. In some embodiments, the housing 21 includes a shell 211 and an end cap 212. The shell 211 has an opening at one end along a first direction, and the end cap 212 closes the opening. The shell 211 includes a first wall 213. Along the thickness direction of the first wall 213, a support portion 232 is disposed on the side of the first support body 231 facing the first wall 213, and an abutment area 23211 abuts against the first wall 213. The first support body 231 has a first surface 2311, and the support portion 232 is disposed on the first surface 2311. The end of the first support body 231 away from the end cap 212 along the first direction has a second guide surface 2316, which is connected to the first surface 2311. The second guide surface 2316 includes an arc surface and / or a sloped plane.

[0270] Along the thickness direction of the first wall 213, the first support 231 includes a first surface 2311 and a third surface 2317 disposed opposite to each other. The first surface 2311 faces the first wall 213, and the support portion 232 is disposed on the first surface 2311. The end of the first support 231 away from the end cap 212 along the first direction has a second guide surface 2316, which is connected to the first guide surface 23214. The second guide surface 2316 can guide the support 23 when it is inserted into the shell, thereby facilitating the insertion of the support 23 into the shell.

[0271] The second guide surface 2316 can be a rounded transition surface located at the end of the first support 231 away from the end cap 212 along the first direction. In this case, the first guide surface 23214 is an arc surface. The second guide surface 2316 can also be an angled transition surface located at the end of the first support 231 away from the end cap 212 along the first direction. In this case, the second guide surface 2316 is an inclined plane.

[0272] Please refer to Figure 17 In the embodiment shown in the figure, the second guide surface 2316 connects the first surface 2311 and the third surface 2317.

[0273] In other embodiments, the end of the first support 231 away from the end cap 212 along a first direction includes a second end face, the second end face being connected to a third surface 2317, and a second guide surface 2316 connecting the second end face and the first surface 2311.

[0274] By providing a second guide surface 2316 on the first support 231, the second guide surface 2316 can play a guiding role during the process of the support 23 being inserted into the shell, thereby facilitating the insertion of the support 23 into the shell.

[0275] Please refer to Figure 18 , Figure 18 This is a side view of the support member 23 provided in some other embodiments of this application. In some other embodiments, the support member 23 further includes a second support body 233, and a support portion 232 is located between the first support body 231 and the second support body 233, and connects the first support body 231 and the second support body 233. The abutment area 23211 abuts against the electrode assembly 22 or the first wall 213 through the second support body 233.

[0276] The second support 233 is the main structure of the support member 23 and can serve as the mounting base for the support part 232. In some embodiments, the second support 233 can be a plate-like structure and can abut against the electrode assembly 22 or the first wall 213. When the second support 233 abuts against the electrode assembly 22, it can reduce the stress on the electrode assembly 22 and lower the risk of damage to the electrode assembly 22. When the second support 233 abuts against the first wall 213, it can reduce the stress on the first wall 213 and lower the risk of metal fragments generated by scraping against the first wall 213.

[0277] The support portion 232 connects between the first support body 231 and the second support body 233, giving the support member 23 higher overall strength. In the early stages of battery cell 20 cycling, the support member 23 provides better constraint on the electrode assembly 22, reducing electrode wrinkling, suppressing electrode thickness growth, delaying the expansion process of the electrode assembly 22, and extending the lifespan of the battery cell 20. In the later stages of battery cell 20 cycling, the support member 23 can still be crushed under the expansion force applied by the electrode assembly 22, thus providing expansion space for the electrode assembly 22.

[0278] When the support portion 232 is disposed on the side of the first support body 231 facing the electrode assembly 22, the abutment area 23211 abuts against the electrode assembly 22 via the second support body 233. When the support portion 232 is disposed on the side of the first support body 231 facing the first wall 213, the abutment area 23211 abuts against the first wall 213 via the second support body 233.

[0279] One of the first support 231 and the second support 233 can abut against the electrode assembly 22, which helps to reduce the stress on the electrode assembly 22, reduce the risk of damage to the electrode assembly 22, and extend the life of the battery cell 20. The other of the first support 231 and the second support 233 can abut against the first wall 213, which helps to reduce the stress on the first wall 213 and reduce the risk of metal debris generated by scraping against the first wall 213.

[0280] In some embodiments, the first support body 231 and the support portion 232 are integrally formed.

[0281] "The first support body 231 and the support part 232 are integrally formed" means that the first support body 231 and the support part 232 are provided as a single structure. For example, the support 23 can be manufactured by injection molding, in which case the first support body 231 and the support part 232 are a single structure.

[0282] By integrally molding the first support body 231 and the support part 232, it is beneficial to improve the overall integrity of the first support body 231 and the support part 232, and improve the connection strength of the first support body 231 and the support part 232, so that the support member 23 can play a better constraining role on the electrode assembly 22 in the early stage of the battery cell 20 cycle.

[0283] In some embodiments, the support member 23 is made of insulating material.

[0284] The support component 23 is made of insulating material, which helps to reduce the risk of short circuit and improve the reliability of the battery cell 20.

[0285] Optionally, the material of the support member 23 includes at least one of polypropylene, polyethylene terephthalate, polyetheretherketone, glass fiber, and polysulfone polymer.

[0286] Polypropylene, polyethylene terephthalate, polyetheretherketone, glass fiber, and polysulfone polymer materials not only have good insulation properties, but are also not easily corroded by electrolytes. In addition, they have a certain strength, which can constrain the electrode assembly 22 in the early stage of battery cell 20 cycling and be crushed in the later stage of battery cell 20 cycling, thereby providing expansion space for electrode assembly 22.

[0287] Please refer to this again. Figure 3 and Figure 4 In some embodiments, the housing 21 includes two first walls 213 disposed opposite to each other, and a support 23 is disposed between each first wall 213 and the electrode assembly 22.

[0288] The outer casing 21 includes two opposing first walls 213. Correspondingly, the battery cell 20 includes two supports 23. Along the thickness direction of the first wall 213, one support 23 is disposed between one first wall 213 and the electrode assembly 22, and the other support 23 is disposed between the other first wall 213 and the electrode assembly 22. That is, a support 23 is respectively disposed on both sides of the electrode assembly 22 along the thickness direction of the first wall 213.

[0289] By providing a support member 23 between each first wall 213 and the electrode assembly 22, the two supports 23 can work together to constrain the electrode assembly 22 during the initial cycle of the battery cell 20. During the later cycle of the battery cell 20, both supports 23 can be crushed, thus providing greater expansion space for the electrode assembly 22.

[0290] Please refer to Figure 3 and Figure 4 In some embodiments, the battery cell 20 further includes an insulating member 24, which covers the outer surface of the electrode assembly 22, and the support member 23 is connected to the insulating member 24.

[0291] The insulating member 24 is an insulating structure covering the outer surface of the electrode assembly 22. In some embodiments, the battery cell 20 includes a plurality of electrode assemblies 22, and one insulating member 24 covers the outer surface of one electrode assembly 22. Among the plurality of electrode assemblies 22, the electrode assembly 22 located at one end along the thickness direction of the first wall 213 is the first electrode assembly, and the support member 23 can be connected to the insulating member 24 covering the first electrode assembly. In other embodiments, the battery cell 20 includes a plurality of electrode assemblies 22, and one insulating member 24 covers the outer surface of a plurality of electrode assemblies 22. Please refer to... Figure 4 ,exist Figure 4In the illustrated embodiment, the battery cell 20 includes two electrode assemblies 22, and an insulating member 24 is correspondingly covered on the outer surface of the two electrode assemblies 22. A support member 23 can be connected to the outer surface of the insulating member 24, for example, the support member 23 is thermally fused to the outer surface of the insulating member 24.

[0292] The insulating element 24 has insulating properties, which can reduce the risk of short circuit due to contact between the electrode assembly 22 and the housing 211. In some embodiments, the insulating element 24 is a Mylar film.

[0293] By connecting the support member 23 to the insulating member 24, the support member 23 can be inserted into the housing along with the electrode assembly 22 when the electrode assembly 22 is inserted into the housing. This helps to maintain the relative position of the support member 23 and the electrode assembly 22, reduces the number of insertions into the housing, and improves production efficiency.

[0294] Please refer to Figure 19 , Figure 19 This is a schematic diagram of the structure of the electrode assembly 22 with finishing adhesive attached according to some embodiments of this application. In some embodiments, the battery cell 20 further includes an expansion member 2216, which is disposed between the electrode assembly 22 and the first wall 213. The expansion member 2216 and the support member 23 are arranged along the thickness direction of the first wall 213. The expansion member 2216 is configured to absorb electrolyte and expand.

[0295] The expansion member 2216 is a component capable of absorbing electrolyte and expanding. Before absorbing electrolyte, the expansion member 2216 has a small volume, which facilitates its placement between the electrode assembly 22 and the first wall 213, and allows the expansion member 2216 and the support member 23 to be stacked along the thickness direction of the first wall 213. The expansion member 2216's ability to absorb electrolyte and expand allows the support member 23 to better abut against the electrode assembly 22 and the first wall 213, reducing the dimensional accuracy requirements for the housing 21, the support member 23, and the electrode assembly 22, thus simplifying manufacturing.

[0296] The expansion component 2216 may include oriented polystyrene, ethylene-ethyl acrylate, etc.

[0297] By providing an expansion member 2216 between the electrode assembly 22 and the first wall 213, and arranging the expansion member 2216 and the support member 23 along the thickness direction of the first wall 213, the expansion member 2216 can absorb electrolyte and expand, allowing the support member 23 to better abut against the electrode assembly 22 and the first wall 213. This facilitates better constraint of the support member 23 on the electrode assembly 22 during the initial cycle of the battery cell 20, while the support member 23 is crushed during the later cycle of the battery cell 20, thus providing expansion space for the electrode assembly 22. On the other hand, the presence of the expansion member 2216 reduces the dimensional accuracy requirements of the outer casing 21, the support member 23, and the electrode assembly 22, making manufacturing easier.

[0298] Please refer to Figure 19 , Figure 19 This is a schematic diagram of the electrode assembly 22 with finishing adhesive applied according to some embodiments of this application. In some embodiments, the electrode assembly 22 includes a first electrode 2213, a second electrode 2214, and a spacer 2215, wherein the first electrode 2213 and the second electrode 2214 have opposite polarities. The first electrode 2213 includes a first electrode segment 22131, the second electrode 2214 includes a second electrode segment 22141, and the spacer 2215 is disposed between the first electrode 2213 and the second electrode 2214. The first electrode 2213, the spacer 2215, and the second electrode 2214 are wound together. The spacer 2215 has a wound end 22151, and the expansion member 2216 is the finishing adhesive connecting the outermost surface of the wound end 22151 and the spacer 2215.

[0299] One of the first electrode 2213 and the second electrode 2214 is a positive electrode, and the other is a negative electrode. For example, when the first electrode 2213 is a positive electrode, the second electrode 2214 is a negative electrode. Or, when the first electrode 2213 is a negative electrode, the second electrode 2214 is a positive electrode.

[0300] The isolator 2215 is an insulating structure disposed between the first electrode 2213 and the second electrode 2214. The isolator 2215 is used to insulate and isolate the first electrode 2213 and the second electrode 2214 to prevent the first electrode 2213 and the second electrode 2214 from coming into contact and causing a short circuit.

[0301] The first electrode 2213, the spacer 2215, and the second electrode 2214 are wound together to form a wound structure, that is, the electrode assembly 22 is a wound electrode assembly. The electrode assembly 22 includes a straight portion 2211 and a bent portion 2212, wherein the straight portion 2211 is the part of the electrode assembly 22 that extends along a straight trajectory, and the bent portion 2212 is connected to one end of the straight portion 2211, and the bent portion 2212 can extend along an arc trajectory. The electrode assembly 22 includes two bent portions 2212, which are respectively connected to the two ends of the straight portion 2211. The first electrode segment 22131 is the part of the first electrode 2213 located in the straight portion 2211, and the second electrode segment 22141 is the part of the second electrode 2214 located in the straight portion 2211.

[0302] The winding termination end 22151 of the spacer 2215 refers to the winding termination end of the spacer 2215. Along the winding direction, the winding termination end 22151 of the spacer 2215 is located at the end of the spacer 2215, and it is located at the outermost edge of the electrode assembly 22. The spacer 2215 also has a winding start end, which serves as the beginning of winding the spacer 2215 and is located inside the electrode assembly 22.

[0303] The expansion member 2216 is a finishing adhesive that bonds the winding end 22151 of the separator 2215 to the outermost surface of the separator 2215, so as to fix the shape of the electrode assembly 22.

[0304] The expansion member 2216 serves both as a finishing adhesive and as an absorbent electrolyte, allowing the support member 23 to better abut against the electrode assembly 22 and the first wall 213. On one hand, by utilizing the location of the finishing adhesive, it reduces the space occupied inside the battery cell 20, thus improving the energy density of the battery cell 20. On the other hand, the expansion member 2216, being a single component, performs multiple functions, simplifying the structure of the battery cell 20.

[0305] This application embodiment also provides a battery device 100, which includes the aforementioned battery cell 20.

[0306] Please refer to Figure 2 and Figure 20 , Figure 20 This is a schematic diagram illustrating the arrangement of multiple battery cells 20 within a battery device 100 according to some embodiments of this application. In some embodiments, the battery device 100 includes a housing 10 and multiple battery cells 20 arranged along the thickness direction of a first wall 213, all of which are housed within the housing 10. The outer surface of the first wall 213 of one battery cell 20 abuts against the outer surface of the first wall 213 of another battery cell 20.

[0307] The battery device 100 may include two, three, four, or more battery cells 20. The multiple battery cells 20 are arranged along the thickness direction of the first wall 213.

[0308] In a plurality of battery cells 20, the outer surface of the first wall 213 of at least one battery cell 20 is attached to the outer surface of the first wall 213 of another battery cell 20, so that the two battery cells 20 are close together.

[0309] Optionally, along the thickness direction of the first wall 213, in every two adjacent battery cells 20, the outer surface of the first wall 213 of one battery cell 20 is attached to the outer surface of the first wall 213 of the other battery cell 20.

[0310] Because the battery cell 20 has a support member 23 inside, the support member 23 can be crushed in the later stages of battery cell 20 cycling, thereby providing expansion space for the electrode assembly 22. Therefore, the outer surface of the first wall 213 of one battery cell 20 can be placed against the outer surface of the first wall 213 of another battery cell 20, reducing the distance between the two battery cells 20, which is beneficial to improving the energy density of the battery device 100.

[0311] This application embodiment also provides an electrical device, which includes the aforementioned battery cell 20, and the battery cell 20 is used to provide electrical energy to the electrical device.

[0312] According to some embodiments of this application, please refer to Figures 3-8 .

[0313] This application provides a battery cell 20, which includes a housing 21, an electrode assembly 22, and a support member 23. The housing 21 has a first wall 213, and the electrode assembly 22 is housed within the housing 21. The electrode assembly 22 includes a flat portion 2211, which includes a first electrode segment 22131 and a second electrode segment 22141 with opposite polarities. The first electrode segment 22131 and the second electrode segment 22141 are stacked along the thickness direction of the first wall 213. The support member 23 is positioned between the first wall 213 and the electrode assembly 22 along the thickness direction of the first wall 213. The support member 23 includes a connected first support body 231 and a support portion 232. Along the thickness direction of the first wall 213, the support portion 232 is disposed on at least one side of the first support body 231. The support portion 232 has an abutment area 23211 furthest from the first support body 231, which abuts against the electrode assembly 22 or the first wall 213, with a gap between the abutment area 23211 and the first support body 231. A support member 23 is provided between the first wall 213 and the electrode assembly 22, abutting against the gap between them to fill the gap. In the early stages of battery cell 20 cycling, the support member 23 constrains the electrode assembly 22, improving electrode wrinkling, suppressing electrode thickness growth, delaying the expansion process of the electrode assembly 22, and extending the lifespan of the battery cell 20. In the later stages of battery cell 20 cycling, due to the gap between the abutment area 23211 and the first support body 231, the support portion 232 is easily crushed under the expansion force applied by the electrode assembly 22, thus providing expansion space for the electrode assembly 22. Furthermore, since a support member 23 is provided between the first wall 213 and the electrode assembly 22, the support member 23 can support the first wall 213, making it less prone to deformation when subjected to external impact. Moreover, during the formation process, the support member 23 can constrain the electrode assembly 22, which helps to reduce gas residue in the electrode assembly 22 during the formation process and reduces the risk of defects such as purple spots and gas marks on the electrode sheet.

[0314] Along the thickness direction of the first wall 213, a support portion 232 is disposed on the side of the first support body 231 facing the first wall 213, and an abutment area 23211 abuts against the first wall 213. The placement of the support portion 232 on the side of the first support body 231 facing the first wall 213 along its thickness direction, and the abutment area 23211 abutting against the first wall 213, allows the first support body 231 to abut against the electrode assembly 22. Compared to the support portion 232, the first support body 231 provides better support for the electrode assembly 22, which helps reduce the stress on the electrode assembly 22, lowers the risk of damage to the electrode assembly 22, and extends the lifespan of the battery cell 20.

[0315] The support portion 232 includes at least one support rib 2321, which is inclinedly disposed on the first support body 231. During the initial cycle of the battery cell 20, the support rib 2321 experiences less stress and can maintain its original shape, allowing the support member 23 to effectively constrain the electrode assembly 22, suppressing the thickness increase of the electrode sheet, delaying the expansion process of the electrode assembly 22, and extending the lifespan of the battery cell 20. During the later cycle of the battery cell 20, the support rib 2321 experiences greater expansion force from the electrode assembly 22, making it easier to crush and providing expansion space for the electrode assembly 22.

[0316] Along the thickness direction of the first wall 213, a support rib 2321 is disposed on the side of the first support body 231 facing the first wall 213, and an abutment area 23211 abuts against the first wall 213. Along the thickness direction of the support rib 2321, the support rib 2321 includes a second surface 23123, which faces the first wall 213. The abutment area 23211 has a first guide surface 23214, which is connected to the second surface 23123. The first guide surface 23214 includes an arc surface and / or a sloped plane. By providing the first guide surface 23214, during the insertion of the support member 23 into the housing, the first guide surface 23214 can abut against the inner surface of the first wall 213, reducing the stress of the support rib 2321 on the first wall 213 and reducing the risk of the support rib 2321 scraping against the first wall 213 and generating metal fragments. During the use of the battery cell 20, the first guide surface 23214 can abut against the inner surface of the first wall 213, reducing the stress of the support rib 2321 on the first wall 213 and reducing the risk of the support rib 2321 scraping against the first wall 213 and generating metal fragments.

[0317] The outer casing 21 includes a housing 211 and an end cap 212. The housing 211 has an opening at one end along a first direction, and the end cap 212 closes the opening. The housing 211 includes a first wall 213. Along the thickness direction of the first wall 213, a support rib 2321 is disposed on the side of the first support body 231 facing the first wall 213, and an abutment area 23211 abuts against the first wall 213. The support rib 2321 includes a first end 23212 disposed opposite to the abutment area 23211, and the first end 23212 is connected to the first support body 231. Along the first direction, the abutment area 23211 is closer to the end cap 212 than the first end 23212, and the first direction is perpendicular to the thickness direction of the first wall 213. The abutment area 23211 is closer to the end cap 212 than the first end 23212. That is, the support rib 2321 is inclined from the first support body 231 toward the end cap 212. In this way, when the support member 23 is inserted into the shell, the support rib 2321 can guide it, thus facilitating the insertion of the support member 23 into the shell.

[0318] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery cell, characterized in that, include: The outer shell has a first wall; An electrode assembly is housed within the housing. The electrode assembly includes a flat portion, which includes a first electrode segment and a second electrode segment with opposite polarities. The first electrode segment and the second electrode segment are stacked along the thickness direction of the first wall. A support member is provided between the first wall and the electrode assembly along the thickness direction of the first wall. The support member includes a connected first support body and a support portion. Along the thickness direction of the first wall, the support portion is disposed on at least one side of the first support body. The support portion has an abutment area furthest from the first support body. The abutment area abuts against the electrode assembly or the first wall. There is a gap between the abutment area and the first support body.

2. The battery cell according to claim 1, characterized in that, Along the thickness direction of the first wall, the support portion is disposed on the side of the first support body facing the first wall, and the abutment area abuts against the first wall.

3. The battery cell according to claim 2, characterized in that, Along the thickness direction of the first wall, the projection of the straight portion lies entirely within the first support body.

4. The battery cell according to claim 1, characterized in that, The support portion includes at least one support rib, which is inclinedly disposed on the first support body.

5. The battery cell according to claim 4, characterized in that, Along the thickness direction of the first wall, the first support has a first surface, the support rib is connected to the first surface, and the angle between the extension direction of the support rib and the first surface is α, satisfying: 20°≤α≤70°.

6. The battery cell according to claim 5, characterized in that, 30°≤α≤60°。 7. The battery cell according to claim 4, characterized in that, The thickness of the first support is H1, and the thickness of the support rib is H2, satisfying: 0.5≤H2 / H1≤3.

8. The battery cell according to claim 7, characterized in that, 1.5≤H2 / H1≤2.

5.

9. The battery cell according to claim 4, characterized in that, The thickness of the first support is H1, which satisfies: 0.1mm≤H1≤0.5mm.

10. The battery cell according to claim 9, characterized in that, 0.2mm≤H1≤0.4mm.

11. The battery cell according to claim 4, characterized in that, The thickness of the supporting rib is H2, which satisfies: 0.15mm≤H2≤1.5mm.

12. The battery cell according to claim 11, characterized in that, 0.3mm≤H2≤0.8mm.

13. The battery cell according to claim 4, characterized in that, Along the thickness direction of the first wall, the supporting rib is disposed on the side of the first support body facing the first wall, the abutting area abuts against the first wall, and along the thickness direction of the supporting rib, the supporting rib includes a second surface, the second surface is disposed facing the first wall, the abutting area has a first guiding surface, the first guiding surface is connected to the second surface, and the first guiding surface includes an arc surface and / or an inclined plane.

14. The battery cell according to claim 4, characterized in that, The outer casing includes a housing and an end cap, the housing having an opening at one end along a first direction, the end cap closing the opening, and the housing including the first wall; Along the thickness direction of the first wall, the supporting rib is disposed on the side of the first support body facing the first wall, the abutting area abuts against the first wall, the supporting rib includes a first end disposed opposite to the abutting area, the first end is connected to the first support body, along the first direction, the abutting area is closer to the end cap than the first end, and the first direction is perpendicular to the thickness direction of the first wall.

15. The battery cell according to claim 4, characterized in that, The outer casing includes a second wall, which is disposed opposite to the electrode assembly along a first direction, the first direction being perpendicular to the thickness direction of the first wall; The support portion includes a plurality of support ribs, each support rib having a first end disposed opposite to the abutment area, the first end being connected to the first support body, the abutment area of ​​one support rib being closer to the second wall than the first end, and the abutment area of ​​another support rib being farther away from the second wall than the first end.

16. The battery cell according to claim 1, characterized in that, The support portion includes an arc-shaped portion, which is connected to the first support body.

17. The battery cell according to claim 16, characterized in that, Along the thickness direction of the first wall, the arcuate portion includes an inner arcuate surface and an outer arcuate surface disposed opposite to each other. The inner arcuate surface faces the first support body, and a portion of the outer arcuate surface abuts against the electrode assembly or the first wall. Along the extension direction of the arcuate portion, at least one end of the arcuate portion is connected to the first support body.

18. The battery cell according to claim 17, characterized in that, Along the extending direction of the arc-shaped portion, both ends of the arc-shaped portion are connected to the first support body.

19. The battery cell according to claim 1, characterized in that, The support has a first weak portion, which is configured to be destroyed when the expansion force applied by the electrode assembly reaches a threshold.

20. The battery cell according to claim 1, characterized in that, The support member includes multiple support portions, which are arranged along a first direction perpendicular to the thickness direction of the first wall.

21. The battery cell according to claim 20, characterized in that, The first support has a second weak portion, which is disposed between two adjacent support portions along the first direction.

22. The battery cell according to claim 21, characterized in that, The first support body is provided with a first groove, and the bottom wall of the first groove includes the second weak part.

23. The battery cell according to claim 22, characterized in that, The first groove extends along the second direction, and the first direction, the second direction, and the thickness direction of the first wall are perpendicular to each other.

24. The battery cell according to claim 22, characterized in that, Along the thickness direction of the first wall, the support portion is disposed on the side of the first support body facing the first wall, the abutment area abuts against the first wall, and the first groove and the support portion are disposed on the surface of the first support body facing the first wall.

25. The battery cell according to any one of claims 1-24, characterized in that, The first support includes a first surface and multiple side surfaces. The support portion is disposed on the first surface, and the multiple side surfaces surround the first surface. At least one set of two adjacent side surfaces are connected by a rounded corner.

26. The battery cell according to any one of claims 1-24, characterized in that, The outer casing includes a housing and an end cap, the housing having an opening at one end along a first direction, the end cap closing the opening, and the housing including the first wall; Along the thickness direction of the first wall, the support portion is disposed on the side of the first support body facing the first wall, the abutment area abuts against the first wall, the first support body has a first surface, the support portion is disposed on the first surface, and the end of the first support body away from the end cap along the first direction has a second guide surface, the second guide surface is connected to the first surface, and the second guide surface includes an arc surface and / or an inclined plane.

27. The battery cell according to any one of claims 1-24, characterized in that, The support also includes a second support body, the support portion being located between the first support body and the second support body and connecting the first support body and the second support body, the abutting area abutting against the electrode assembly or the first wall through the second support body.

28. The battery cell according to any one of claims 1-24, characterized in that, The first support body and the support part are integrally formed.

29. The battery cell according to any one of claims 1-24, characterized in that, The support component is made of insulating material.

30. The battery cell according to any one of claims 1-24, characterized in that, The material of the support includes at least one of polypropylene, polyethylene terephthalate, polyetheretherketone, glass fiber, and polysulfone polymer.

31. The battery cell according to any one of claims 1-24, characterized in that, The housing includes two first walls disposed opposite each other, and the support is disposed between each first wall and the electrode assembly.

32. The battery cell according to any one of claims 1-24, characterized in that, The battery cell also includes an insulating component, which covers the outer surface of the electrode assembly, and the support component is connected to the insulating component.

33. The battery cell according to any one of claims 1-24, characterized in that, The battery cell also includes an expansion member disposed between the electrode assembly and the first wall. The expansion member and the support member are arranged along the thickness direction of the first wall. The expansion member is configured to absorb electrolyte and expand.

34. The battery cell according to claim 33, characterized in that, The electrode assembly includes a first electrode, a second electrode, and a separator. The first electrode and the second electrode have opposite polarities. The first electrode includes a first electrode segment, and the second electrode includes a second electrode segment. The separator is disposed between the first electrode and the second electrode. The first electrode, the separator, and the second electrode are wound together. The separator has a winding end. The expansion member is a finishing adhesive that connects the winding end and the outermost surface of the separator.

35. A battery device, characterized in that, Includes the battery cell according to any one of claims 1-34.

36. The battery device according to claim 35, characterized in that, The battery device includes a housing and a plurality of battery cells arranged along the thickness direction of the first wall. The plurality of battery cells are all housed in the housing, and the outer surface of the first wall of one battery cell is attached to the outer surface of the first wall of another battery cell.

37. An electrical device, characterized in that, Includes a battery cell according to any one of claims 1-34, the battery cell being used to provide electrical energy to the electrical device.

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