Battery and battery module

Abstract

The utility model provides a battery and a battery module. The battery comprises a cover plate assembly, the shell is provided with an opening end, and the cover plate assembly covers the opening end; the naked battery cell is arranged in the shell, the naked battery cell comprises a first surface close to the cover plate assembly, at least one end of the diaphragm in the length direction is constructed as a first free end, and the first free end is bent towards the first surface; the insulating layer is arranged between the naked battery cell and the shell, and the insulating layer and the cover plate assembly are in hot melting connection to form a hot melting connection part; the restraining layer is connected to the outer side of the naked battery cell and covers at least part of the first free end, and the restraining layer is used for enabling the first free end and the hot melting connecting part to be arranged at an interval; and the orthographic projection of the restraining layer on the naked battery cell is at least partially overlapped with the orthographic projection of the hot melting connection part on the naked battery cell. According to the battery and the battery module provided by the invention, the position of the restraining layer corresponds to the position of the hot melting connecting part, so that the first free end and all the hot melting connecting parts of the battery are arranged at intervals, and the risk that the diaphragm shrinks after being heated is further reduced.

Description

Technical Field

[0001] This application relates to the field of energy storage technology, and in particular to a battery and a battery module. Background Technology

[0002] The battery includes a casing, a cover assembly connected to the casing, bare cells electrically connected to the cover assembly, and an insulating layer (or Mylar film) located between the casing and the bare cells. During battery assembly, the insulating layer needs to be thermally fused to the cover assembly.

[0003] A bare battery cell includes a positive electrode, a negative electrode, and a separator that separates the positive and negative electrodes. During the thermal fusion connection of the insulating layer and the cover plate assembly, if the separator is too close to the fusion point, it may shrink due to heat, exposing the electrodes and adversely affecting the electrochemical performance and safety of the battery. Utility Model Content

[0004] In view of this, the purpose of this application is to propose a battery and a battery module to at least partially solve the problem of separator shrinkage due to heat caused by the bare cell separator being too close to the hot melt point.

[0005] Based on the above objectives, a first aspect of this application provides a battery, comprising: a cover assembly; a housing having an open end, the cover assembly covering the open end; and a bare cell disposed within the housing, the bare cell having a stacked structure, the stacked structure including a plurality of positive electrode plates and a plurality of negative electrode plates alternately arranged along a first direction, and a separator isolating the positive electrode plates and the negative electrode plates; the separator is folded in a "Z" shape along its length to form a plurality of insertion spaces, the plurality of insertion spaces including a first space and a second space alternately arranged along the first direction, the positive electrode plates being inserted into the first space, and the negative electrode plates being inserted into the second space; the bare cell The diaphragm includes a first surface near the cover assembly, at least one end of the diaphragm along its length is configured as a first free end, the first free end being bent toward the first surface; an insulating layer disposed between the bare cell and the housing, the insulating layer being thermally fused to the cover assembly to form a thermally fused connection; a restraining layer connected to the outside of the bare cell and covering at least a portion of the first free end, the restraining layer being used to space the first free end from the thermally fused connection; and along a second direction, the orthographic projection of the restraining layer onto the bare cell at least partially coincides with the orthographic projection of the thermally fused connection onto the bare cell, the second direction being perpendicular to the first surface.

[0006] Optionally, the bare cell includes a first side and a second side disposed opposite to each other along the first direction, and the first surface is connected to both the first side and the second side; when the first free end is connected to one of the first side and the second side, the restraint layer is connected to at least the other of the first side and the second side.

[0007] Optionally, the restraint layer extends from the first side along the first surface to the second side.

[0008] Optionally, the diaphragm includes two first free ends, one of which is connected to the first side and the other of which is connected to the second side, with the same restraint layer covering at least a portion of each of the two first free ends.

[0009] Optionally, in the first direction, the restraint layer is parallel to the first surface, and the restraint layer is taut and straight.

[0010] Optionally, the battery includes a plurality of restraint layers, which are spaced apart along a third direction; the first direction, the second direction, and the third direction are mutually perpendicular.

[0011] Optionally, the restraint layer is continuously disposed along a third direction, and at least one end of the restraint layer extends to the edge of the first surface of the bare cell.

[0012] Optionally, the cover plate assembly includes a cover plate body and a lower insulating member connected to the cover plate body on the side near the bare cell; the portion of the insulating layer located between the lower insulating member and the housing is thermally fused to the lower insulating member, and the thermally fused connection is formed on the lower insulating member.

[0013] Optionally, the restraint layer includes a base layer and an adhesive layer disposed on the surface of the base layer, wherein the base layer is connected to the bare battery cell through the adhesive layer.

[0014] Based on the same inventive concept, the second aspect of this application also provides a battery module, including the battery as described in the first aspect.

[0015] As can be seen from the above, the battery and battery module provided in this application have a restraint layer on the bare cell. The first free end can be covered by the restraint layer, so that a gap is formed between the first free end and the hot-melt connection, thereby hindering heat transfer. By limiting the orthographic projection of the restraint layer to at least partially overlap with the orthographic projection of the hot-melt connection, the position of the restraint layer can be made to correspond to the position of the hot-melt connection, so that the first free end and all the hot-melt connections of the battery are spaced apart, thereby reducing the risk of thermal shrinkage of the separator. This helps to ensure that the separator can completely cover the positive and negative electrode plates of the bare cell, ensuring the electrical performance and safety of the battery. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in this application or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a partial schematic diagram of a battery with a first structure according to an embodiment of this application;

[0018] Figure 2 for Figure 1 Schematic diagram of the cross section AA in the middle;

[0019] Figure 3 for Figure 1 A cross-sectional schematic diagram of the second structure at section AA;

[0020] Figure 4 for Figure 3 Schematic diagram of the cross-section BB in the middle;

[0021] Figure 5 for Figure 3 A cross-sectional schematic diagram of the third structure in the BB section;

[0022] Figure 6 for Figure 1 A cross-sectional schematic diagram of the fourth structure at section AA;

[0023] Figure 7 for Figure 6 An enlarged schematic diagram of section C;

[0024] Figure 8 This is a schematic diagram showing the connection between the bare cell and the restraint layer in the fifth structure.

[0025] Explanation of reference numerals in the attached figures:

[0026] 100. Cover plate assembly; 110. Cover plate body; 120. Lower insulation component; 121. Insulation body; 122. Lower protrusion; 130. Positive terminal post; 140. Negative terminal post; 150. Connecting piece;

[0027] 200, Bare cell; 210, Positive electrode plate; 211, Positive electrode tab; 220, Negative electrode plate; 221, Negative electrode tab; 230, Separator; 231, First free end; 231a, Left first free end; 231b, Right first free end; 240, First space; 250, Second space; 260, First surface; 270, First side surface; 280, Second side surface;

[0028] 300. Insulation layer;

[0029] 400, restraint layer; 410, base layer; 420, adhesive layer;

[0030] 500. Hot melt connection;

[0031] 600, shell; 610, open end. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0033] It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components described in these embodiments do not limit the scope of this application.

[0034] At the same time, it should be understood that, for ease of description, the dimensions of the various parts shown in the accompanying drawings are not drawn according to actual scale.

[0035] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the scope of this application and its application or use.

[0036] It should be noted that, unless otherwise defined, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," and similar terms used in the embodiments of this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are only used to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0037] Figure 1 A partial schematic diagram of the first type of battery structure is shown, such as... Figure 1 The battery includes a cover assembly 100 and a housing 600, the housing 600 having an opening end 610, the cover assembly 100 covering the opening end 610.

[0038] For example, the top of the housing 600 may be configured as an open end 610.

[0039] For example, the cover plate assembly 100 includes a cover plate body 110, a lower insulator 120, a positive terminal 130, and a negative terminal 140. The cover plate body 110 can be a plate-like structure and can be welded to the opening end 610 of the housing 600. The lower insulator 120 is connected to the side of the cover plate body 110 located inside the housing 600. The positive terminal 130 is insulated and sealed through the cover plate body 110 and the lower insulator 120, with the portion of the positive terminal 130 located outside the housing 600 used for electrical connection to an external circuit. Similarly, the negative terminal 140 is insulated and sealed through the cover plate body 110 and the lower insulator 120, with the portion of the negative terminal 140 located outside the housing 600 used for electrical connection to an external circuit.

[0040] Figure 2 Showing Figure 1 A schematic diagram of the cross-section AA in the middle, as shown below. Figure 2 The battery also includes bare cells 200, which are disposed within the housing 600. The bare cells 200 have a stacked structure, and the stacked structure includes a first direction (e.g., along the first direction). Figure 2The system includes multiple positive electrode plates 210 and multiple negative electrode plates 220 arranged alternately in the X direction, and a separator 230 that isolates the positive electrode plates 210 and the negative electrode plates 220. The separator 230 is folded in a "Z" shape along its length to form multiple insertion spaces, including a first space 240 and a second space 250 arranged alternately along a first direction. The positive electrode plates 210 are inserted into the first space 240, and the negative electrode plates 220 are inserted into the second space 250.

[0041] For example, each positive electrode 210 has a portion extending from the opening of the first space 240, and the extended portions of multiple positive electrode 210 are stacked and connected to form a positive electrode tab 211. The positive electrode tab 211 can be electrically connected to the positive electrode post 130 through the connecting piece 150. Each negative electrode 220 has a portion extending from the opening of the second space 250, and the extended portions of multiple negative electrode 220 are stacked and connected to form a negative electrode tab 221. The negative electrode tab 221 can be electrically connected to the negative electrode post 140 through the connecting piece 150.

[0042] The bare cell 200 includes a first surface 260 near the cover assembly 100, and at least one end of the separator 230 along its length is configured as a first free end 231.

[0043] like Figure 1 and Figure 2 The battery also includes an insulating layer 300, which is disposed between the bare cell 200 and the casing 600. The insulating layer 300 and the cover plate assembly 100 are thermally fused together to form a thermally fused connection part 500.

[0044] For example, the insulating layer 300 is thermally fused to the lower insulating member 120 in the cover plate assembly 100.

[0045] For example, the diaphragm 230 has a starting end and a ending end along its length, at least one of which is configured as a first free end 231.

[0046] by Figure 2 Taking the structure and orientation shown as an example for further explanation, the first surface 260 is the top surface of the main body of the bare cell 200. The top of the insulating layer 300 is an open structure and is fitted onto the outside of the lower insulating member 120. The first free end 231 of the diaphragm 230 extends upward beyond the first surface 260. If the first free end 231 is not restrained, it will approach or contact the lower insulating member 120. When the insulating layer 300 and the lower insulating member 120 of the cover assembly 100 are thermally fused together, the heat radiated outward from the formed thermally fused connection 500 may be transferred to the first free end 231, causing the diaphragm 230 to shrink due to heat and no longer be able to completely cover the electrode (including at least one of the positive electrode 210 and the negative electrode 220).

[0047] To avoid the above problems, the first free end 231 can be restrained. Figure 3 Showing Figure 1 A cross-sectional schematic diagram of the second structure with section AA in the middle, as shown below. Figure 3 The battery includes a restraint layer 400, which is connected to the outside of the bare cell 200 and covers at least part of the first free end 231. The restraint layer 400 is used to bend the first free end 231 toward the first surface 260 so as to be spaced apart from the heat-fused connection portion 500.

[0048] At this time, since there is a gap between the first free end 231 covered by the restraint layer 400 and the heat-fusion connection portion 500, when the insulation layer 300 and the lower insulation member 120 are heat-fused together, the gap between the first free end 231 and the heat-fusion connection portion 500 can hinder the heat transmission, so as to effectively reduce the heat transferred from the heat-fusion connection portion 500 to the first free end 231, thereby reducing the risk of thermal shrinkage of the diaphragm 230.

[0049] Figure 4 Showing Figure 3 A cross-sectional diagram of section BB is shown below. Figure 4 The applicant's research revealed that, due to the thinness of the diaphragm 230, the first free ends 231 on both sides adjacent to the restraint position gradually return to their upward-extending state from the first surface 260 as they move away from the restraint position. Furthermore, if the position of the heat-fused connection 500 is disregarded, and only a portion of the first free end 231 is restrained, then even when the heat-fused connection 500 and the restraint layer 400 are misaligned by a certain distance, an unrestrained area of ​​the first free end 231 may still approach the heat-fused connection 500. Consequently, the heat radiated outward from the heat-fused connection 500 will still be transferred to the unrestrained first free end 231, potentially causing localized thermal shrinkage of the diaphragm 230.

[0050] Figure 5 Showing Figure 3 A cross-sectional schematic diagram of the third structure in the BB section is shown below. Figure 5 To solve the above problem, along the second direction (such as...) Figure 5 In the Z direction, the orthographic projection of the restraint layer 400 on the bare cell 200 (hereinafter referred to as the restraint layer projection) and the orthographic projection of the hot melt connection portion 500 on the bare cell 200 (hereinafter referred to as the hot melt projection) at least partially coincide, and the second direction Z is perpendicular to the first surface 260.

[0051] For example, along a third party (such as Figure 5 In the Y direction, the hot melt projection is located within the constraint layer projection to ensure that the area of ​​the first free end 231 corresponding to the hot melt connection portion 500 is covered by the constraint layer 400. The first direction, the second direction, and the third direction are mutually perpendicular.

[0052] Based on the foregoing, it can be understood that at the location where the restraint layer 400 is provided on the bare cell 200, the first free end 231 can be covered by the restraint layer 400, so that a gap is formed between the first free end 231 and the heat-fused connection portion 500, thereby hindering heat transfer. Therefore, in this embodiment, by limiting the orthographic projection of the restraint layer 400 and the orthographic projection of the heat-fused connection portion 500 to at least partially overlap, the location of the restraint layer 400 can be made to correspond to the location of the heat-fused connection portion 500, so that the first free end 231 and all the heat-fused connections 500 of the battery are spaced apart, thereby reducing the risk of thermal shrinkage of the separator 230, and helping to ensure that the separator 230 can completely cover the positive electrode 210 and negative electrode 220 of the bare cell 200, thus ensuring the electrical performance and safety of the battery.

[0053] like Figure 3 In some embodiments, the bare cell 200 includes a first side 270 and a second side 280 disposed opposite to each other along a first direction, and the first surface 260 is connected to both the first side 270 and the second side 280; when the first free end 231 is connected to one of the first side 270 and the second side 280, the restraint layer 400 is connected to at least the other of the first side 270 and the second side 280.

[0054] For example, the first side 270 and the second side 280 are surfaces of the bare cell 200 disposed along the thickness direction of the negative electrode 220.

[0055] by Figure 3 Taking the structure and orientation shown as an example, the first free end 231 on the left side is defined as the left first free end 231a. The left first free end 231a is connected to the second side 280. The restraint layer 400 covering the left first free end 231a can connect to the first side 270 at the same time as connecting the left first free end 231a, so as to continuously apply a downward pulling force to the left first free end 231a, ensuring that the left first free end 231a can be more firmly attached to the first surface 260, thereby preventing the part of the left first free end 231a covered by the restraint layer 400 from approaching or contacting the heat-fused connection part 500, and reducing the risk of the diaphragm 230 shrinking due to heat.

[0056] Figure 6 Showing Figure 1 A cross-sectional diagram of the fourth structure at section AA is shown below. Figure 6 In some embodiments, the restraint layer 400 extends from the first side 270 along the first surface 260 to the second side 280.

[0057] by Figure 6Taking the structure and orientation shown as an example, the restraint layer 400 covering the left first free end 231a extends from the second side 280 through the first surface 260 to the first side 270. At this time, the restraint layer 400 completely covers the left first free end 231a along its extension direction, which can make the connection area between the restraint layer 400 and the left first free end 231a larger, which helps to improve the connection reliability between the restraint layer 400 and the left first free end 231a.

[0058] Meanwhile, since the restraint layer 400 is connected to the first side 270 and the second side 280 at the same time, even if the connection between the restraint layer 400 and the left first free end 231a fails, the restraint layer 400 can still remain above the left first free end 231a and exert a stable downward pressure on the left first free end 231a, ensuring that the left first free end 231a covered by the restraint layer 400 can remain spaced apart from the heat-fused connection portion 500, thereby reducing the risk of the diaphragm 230 shrinking due to heat.

[0059] like Figure 3 and Figure 6 In some embodiments, the diaphragm 230 includes two first free ends 231, one of which is connected to a first side 270 and the other is connected to a second side 280, with the same restraint layer 400 covering at least a portion of the respective area of ​​the two first free ends 231.

[0060] In this embodiment, both the starting and ending ends of the diaphragm 230 are constructed as first free ends 231. Figure 3 Taking the structure and orientation shown as an example, the first free end 231 on the right side is defined as the right first free end 231b, which is connected to the first side surface 270. In this embodiment, along the extending direction of the restraint layer 400, the same restraint layer 400 covers a portion of the left first free end 231a and the entire area of ​​the right first free end 231b. At this time, the same restraint layer 400 can simultaneously restrain both the left first free end 231a and the right first free end 231b, ensuring that the portions of the two first free ends 231 covered by the restraint layer 400 are spaced apart from the adjacent heat-fused connection portion 500, thereby reducing the risk of thermal shrinkage of the separator 230. Simultaneously, the number of restraint layers 400 can be reduced, thereby lowering the battery manufacturing cost and assembly difficulty, and facilitating mass production.

[0061] like Figure 6 In some embodiments, in the first direction, the restraint layer 400 is parallel to the first surface 260, and the restraint layer 400 is taut and flat.

[0062] The taut restraint layer 400 ensures good restraint on the first free end 231, preventing the first free end 231 covered by the restraint layer 400 from approaching the heat-fused connection portion 500. At the same time, the taut restraint layer 400 can also provide a certain degree of constraint on the stacked structure of the bare cell 200 in the first direction, ensuring that the positive electrode 210, negative electrode 220 and separator 230 of the bare cell 200 will not be misaligned, which helps to ensure the electrical performance and safety of the battery.

[0063] like Figure 5 In some embodiments, the battery includes a plurality of restraint layers 400, which are spaced apart along a third direction.

[0064] For example, along a third direction, the spacing between multiple adjacent restraint layers 400 can be the same or different.

[0065] In this embodiment, multiple restraint layers 400 are spaced apart along a third direction. On the one hand, this makes the restraint force exerted by the restraint layers 400 on the bare cell 200 and the first free end 231 more uniform, preventing stress concentration and helping to improve the electrical performance and safety of the battery. On the other hand, by restraining multiple areas of the first free end 231 with multiple restraint layers 400, heat-fused connections 500 can be formed at the corresponding positions of these areas, which helps to improve the connection reliability between the insulating layer 300 and the cover assembly 100, ensuring good insulation performance between the bare cell 200 and the casing 600, thereby improving the safety of the battery.

[0066] It should be noted that the location of the restraint layer 400 can be designed according to the structure of the lower insulating part 120, the location of the heat-fusion connection part 500, the structure of the bare cell 200, the location of the positive terminal 130 or the location of the negative terminal 140, and is not limited here.

[0067] Figure 8 A schematic diagram showing the connection between the bare cell 200 and the restraint layer 400 in the fifth structure is shown, as follows. Figure 6 and Figure 8 In some embodiments, the restraint layer 400 is continuously disposed along a third direction, and at least one end of the restraint layer 400 extends to the edge of the first surface 260 of the bare cell 200.

[0068] To further constrain a larger area of ​​the first free end 231, the constraining layer 400 in this embodiment extends continuously from one end of the bare cell 200 along a third direction to the other end. During the extension of the constraining layer 400, it can pass through the entire heat-fused connection portion 500, and the area of ​​the first free end 231 covered by the constraining layer 400 is spaced apart from the heat-fused connection portion 500. This can minimize the possibility of the first free end 231 approaching or contacting the heat-fused connection portion 500 as a whole, thereby further preventing the diaphragm 230 from shrinking due to heat.

[0069] like Figure 3 In some embodiments, the portion of the insulating layer 300 located between the lower insulating member 120 and the housing 600 is thermally fused to the lower insulating member 120, and the thermally fused connection portion 500 is formed in the lower insulating member 120.

[0070] For example, such as Figure 3 The lower insulating member 120 may include a plate-shaped insulating body 121 and a lower protrusion 122 located at the edge of the insulating body 121. The insulating layer 300 is thermally fused to the lower protrusion 122, and the thermally fused connection portion 500 is also formed at the lower protrusion 122.

[0071] The cover plate body 110 of the cover plate assembly 100 is fixedly connected to the housing 600, and the lower insulating member 120 is fixedly connected to the cover plate body 110. Therefore, the lower insulating member 120 can serve as the positioning basis for the insulating layer 300. After the insulating layer 300 and the lower insulating member 120 are thermally fused together, the relative position between the insulating layer 300 and the housing 600 can be kept unchanged, so that the insulating layer 300 can isolate the bare battery cell 200 from the housing 600, ensuring that the bare battery cell 200 remains insulated from the housing 600 under the action of the insulating layer 300.

[0072] Meanwhile, after the first free end 231 is covered by the restraint layer 400, the first free end 231 can be located below the lower insulating member 120. The heat-fusion connection portion 500 formed on the lower insulating member 120 can be spaced apart from the first free end 231 covered by the restraint layer 400 to prevent the heat of the heat-fusion connection portion 500 from being transferred to the first free end 231, and further avoid the situation where the diaphragm 230 shrinks due to heat.

[0073] Figure 7 for Figure 6 An enlarged diagram of part C, as shown below. Figure 7 In some embodiments, the restraint layer 400 includes a base layer 410 and an adhesive layer 420 disposed on the surface of the base layer 410, wherein the base layer 410 is connected to the bare battery cell 200 through the adhesive layer 420.

[0074] For example, the restraint layer 400 can be an insulating tape.

[0075] For example, the base layer 410 can be an insulating material layer.

[0076] The connection between the restraint layer 400 and the bare cell 200 is achieved by bonding. On the one hand, this reduces the assembly difficulty of the restraint layer 400 and improves the assembly efficiency. On the other hand, a relatively reliable connection structure can be formed between the restraint layer 400 and the first free end 231, as well as between the restraint layer 400 and the first side 270 or the second side 280. This ensures that the restraint layer 400 can provide a relatively stable restraint effect on the first free end 231 corresponding to the heat-fused connection part 500, so that the first free end 231 and the heat-fused connection part 500 are kept at a distance, thereby giving the battery a higher level of safety.

[0077] Based on the same inventive concept and in conjunction with the descriptions of the batteries in the above embodiments, this embodiment provides a battery module that has the corresponding technical effects of the batteries in the above embodiments, which will not be repeated here.

[0078] A battery module includes the battery as described in the above embodiments.

[0079] It should be noted that some embodiments of this application have been described above. Other embodiments are within the scope of the appended claims.

[0080] The various embodiments in this application are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0081] The description in this application is given for illustrative purposes and is not intended to be exhaustive or to limit the application to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described to better illustrate the principles and practical application of this application and to enable those skilled in the art to understand this application and design various embodiments with various modifications suitable for a particular purpose.

[0082] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of this application is limited to these examples; under the concept of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of the embodiments of this application as described above, which are not provided in detail for the sake of brevity.

[0083] Although this application has been described in conjunction with specific embodiments thereof, many substitutions, modifications and variations of these embodiments will be apparent to those skilled in the art from the foregoing description.

[0084] The embodiments of this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of this application. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the embodiments of this application should be included within the protection scope of this application.

Claims

1. A battery, characterized in that, include: Cover plate assembly; A housing having an open end, the cover assembly covering the open end; A bare battery cell is disposed within the housing. The bare battery cell has a stacked structure, which includes a plurality of positive electrode plates and a plurality of negative electrode plates alternately arranged along a first direction, and a separator separating the positive electrode plates and the negative electrode plates. The separator is folded in a "Z" shape along its length to form a plurality of insertion spaces. The plurality of insertion spaces include a first space and a second space alternately arranged along the first direction. The positive electrode plate is inserted into the first space, and the negative electrode plate is inserted into the second space. The bare battery cell includes a first surface near the cover plate assembly. At least one end of the separator along its length is configured as a first free end, and the first free end is bent toward the first surface. An insulating layer is disposed between the bare cell and the housing, and the insulating layer is thermally fused to the cover plate assembly to form a thermally fused connection. A restraint layer is connected to the outside of the bare cell and covers at least a portion of the first free end. The restraint layer is used to space the first free end from the hot-melt connection portion. Along a second direction, the orthographic projection of the restraint layer on the bare cell at least partially coincides with the orthographic projection of the hot-melt connection portion on the bare cell. The second direction is perpendicular to the first surface.

2. The battery according to claim 1, characterized in that, The bare cell includes a first side and a second side disposed opposite to each other along the first direction, and the first surface is connected to both the first side and the second side; when the first free end is connected to one of the first side and the second side, the restraint layer is connected to at least the other of the first side and the second side.

3. The battery according to claim 2, characterized in that, The restraint layer extends from the first side along the first surface to the second side.

4. The battery according to claim 2, characterized in that, The diaphragm includes two first free ends, one of which is connected to the first side and the other of which is connected to the second side, and the same restraint layer covers at least a portion of the respective area of ​​the two first free ends.

5. The battery according to claim 1, characterized in that, In the first direction, the restraint layer is parallel to the first surface, and the restraint layer is taut and straight.

6. The battery according to claim 1, characterized in that, The battery includes a plurality of restraint layers, which are spaced apart along a third direction; the first direction, the second direction, and the third direction are mutually perpendicular.

7. The battery according to claim 1, characterized in that, The restraint layer is continuously disposed along a third direction, and at least one end of the restraint layer extends to the edge of the first surface of the bare cell.

8. The battery according to claim 1, characterized in that, The cover plate assembly includes a cover plate body and a lower insulating member connected to the cover plate body on the side near the bare cell; the portion of the insulating layer located between the lower insulating member and the housing is thermally fused to the lower insulating member, and the thermally fused connection portion is formed on the lower insulating member.

9. The battery according to claim 1, characterized in that, The restraint layer includes a base layer and an adhesive layer disposed on the surface of the base layer, wherein the base layer is connected to the bare battery cell through the adhesive layer.

10. A battery module, characterized in that, Includes the battery as described in any one of claims 1 to 9.

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