Battery

Abstract

The invention discloses a battery, and relates to the technical field of batteries, the battery comprises a shell, a cover plate, a battery cell and an insulating film, the insulating film, a diaphragm and an electrode plate are matched by adjusting the distance L from the outer edge, facing a second end, of a reference electrode plate to the outer edge, facing the second end, of the battery cell, the thickness D1 of the insulating film and the elastic modulus E of the diaphragm, so that the battery cell is formed. Therefore, the insulation film and the cover plate are matched, the spacing distance between the insulation film and the cover plate is in a proper interval, the insulation performance between the battery cell and the shell is ensured, and when the cover plate and the shell are welded, the spacing distance between the insulation film and the cover plate can avoid the situation that the battery cell is damaged due to the fact that the spacing distance between the insulation film and the cover plate is small. And the phenomenon that the insulating film is welded through and melted in the welding process is avoided.

Description

[0001] This application is a divisional application of the patent application No. 202510408549.2, with the application date of April 2, 2025, and the invention name of "Battery and battery module, battery pack". TECHNICAL FIELD

[0002] The present application relates to the technical field of batteries, in particular to a battery. BACKGROUND

[0003] The laminated battery is a kind of lithium ion battery, which assembles the positive electrode sheet, the diaphragm and the negative electrode sheet in order to form a laminated battery cell with a multi-layer structure. Compared with the traditional winding type battery, the laminated battery has higher space utilization and more uniform current distribution, which is suitable for high energy density and high power application scenarios, such as electric vehicles and energy storage systems.

[0004] The diaphragm plays a key role in the laminated battery. In the assembly process of the laminated battery, the diaphragm is usually arranged between the positive electrode sheet and the negative electrode sheet to prevent direct contact between the two and cause short circuit, and the diaphragm is usually wound on the outside of the positive electrode sheet and the negative electrode sheet to prevent the positive electrode sheet and the negative electrode sheet from directly contacting the battery shell.

[0005] The diaphragm wound on the outside of the positive electrode sheet and the negative electrode sheet usually has an insulating tape attached to the end of the diaphragm to make the diaphragm winding compact. However, in different application scenarios, the end of the diaphragm of each battery cell (i.e. the end position of the diaphragm winding) may be distributed on different surfaces. Due to the compact structure of the part of the diaphragm end where the insulating tape is attached and the relatively loose area where the insulating tape is not attached, this difference will cause the diaphragm on one side of the battery to have a difference in flatness, which will affect the subsequent coating of the insulating layer. SUMMARY

[0006] The purpose of the present application is to provide a battery which matches the insulating film, the diaphragm and the electrode sheet to reduce the influence of the diaphragm on the coating of the insulating film, so as to solve the problem that the diaphragm of the existing battery has a difference in flatness and easily affects the coating of the insulating film.

[0007] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present application is as follows:

[0008] A battery comprises:

[0009] A housing having a first end and a second end arranged oppositely in a first direction, and the housing is provided with a receiving cavity, and the first end is provided with an opening communicating the receiving cavity with the external environment;

[0010] A cover plate connected to the opening to isolate the receiving cavity from the external environment;

[0011] The electric core comprises a diaphragm and a plurality of electrode sheets, wherein the plurality of electrode sheets are stacked to form a discontinuous stacked structure; the diaphragm is arranged between two adjacent electrode sheets and covers the outside of the stacked structure; and the diaphragm has an end, which is fixed to one side of the electric core facing the first end; the number of the electric core is at least two, two electric cores are arranged in the accommodating cavity, and two adjacent electric cores are arranged in a direction perpendicular to the first direction; and the ends of the two electric cores are arranged on different sides of the stacked structure, and the end of at least one electric core is fixed to one side of the electric core facing the first end;

[0012] The insulating film covers the outside of the electric core and extends towards the first end, and the insulating film is provided with a notch facing the cover plate to avoid the side of the electric core provided with the end;

[0013] In the first direction, the electrode sheet in the outermost layer and close to the second end is referred to as a reference electrode sheet, the distance from the outer edge of the reference electrode sheet facing the second end to the outer edge of the electric core facing the second end is L, the thickness of the insulating film is D1, and the elastic modulus of the diaphragm is E, and the above parameters satisfy:

[0014] 250≤(D1×E) / L≤4000,

[0015] And the distance L satisfies: 3≤L≤200μm; and / or the thickness D1 of the insulating film satisfies: 50≤D1≤150μm; and / or the elastic modulus E of the diaphragm satisfies: 200≤E≤2000Mpa.

[0016] Compared with the prior art, the battery implemented by the application has the following beneficial effects:

[0017] By adjusting the distance L from the outer edge of the reference electrode sheet facing the second end to the outer edge of the electric core facing the second end, the thickness D1 of the insulating film, and the elastic modulus E of the diaphragm, the battery and the battery pack can match the insulating film, the diaphragm and the electrode sheet, so that the insulating film and the cover plate form a matching fit, and the spacing distance between the insulating film and the cover plate is within a suitable interval, thereby ensuring the insulation performance between the electric core and the shell, and when the cover plate and the shell are welded, the spacing distance between the insulating film and the cover plate can avoid the phenomenon that the insulating film is welded and melted in the welding process due to the small spacing distance between the insulating film and the cover plate. The battery module and the battery pack of the application apply the above-mentioned battery and have the beneficial effects of the above-mentioned battery. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a schematic view of the battery in embodiment 1 of the application;

[0019] Figure 2 is a schematic view of the housing in Embodiment 1 of the present application;

[0020] Figure 3 is a plan view of the battery in Embodiment 1 of the present application;

[0021] Figure 4 is a schematic view of Figure 3 in Embodiment 1 of the present application;

[0022] Figure 5 is an enlarged view of Figure 4 in Embodiment 1 of the present application;

[0023] Figure 6 is an enlarged view of Figure 4 in Embodiment 1 of the present application;

[0024] Figure 7 is a schematic view of the stacked structure in Embodiment 1 of the present application in which the stacking direction is perpendicular to the first direction;

[0025] Figure 8 is a schematic view of the stacked structure in Embodiment 1 of the present application in which the stacking direction is parallel to the first direction;

[0026] Figure 9 is a schematic view of the battery pack in Embodiment 2 of the present application;

[0027] Figure 10 is a schematic view of the housing in Embodiment 2 of the present application;

[0028] Figure 11 is a plan view of the battery pack in Embodiment 2 of the present application;

[0029] Figure 12 is a schematic view of Figure 11 in Embodiment 2 of the present application;

[0030] Figure 13 is an enlarged view of Figure 12 in Embodiment 2 of the present application;

[0031] Figure 14 is an enlarged view of Figure 12 in Embodiment 2 of the present application;

[0032] Figure 15 is a schematic view of the battery pack in Embodiment 2 of the present application in which the fixing member is at the rear side;

[0033] Figure 16 is a schematic view of the battery pack in Embodiment 2 of the present application in which the fixing member is at the front side.

[0034] In the figure, 100, battery; X, first direction; Y, second direction; Z, third direction; 1, shell; 1a, first end; 1b, second end; 1c, accommodating cavity; 2, cover plate; 3, opening; 4, battery cell; 4a, diaphragm; 4b, electrode sheet; 4b1, positive electrode sheet; 4b2, negative electrode sheet; 5, fixing member; 6, insulating film; 6a, notch; 7, insulating member; 8, barrier member. DETAILED DESCRIPTION

[0035] The specific embodiments of the present application will be further described in conjunction with the drawings and examples. The following examples are used to illustrate the present application, but are not used to limit the scope of the present application.

[0036] In the description of the present application, it should be understood that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element. The terms "mount", "connect", "connection" should be interpreted broadly, for example, can be fixed connection, can also be detachable connection, or integrally connected; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through an intermediate medium, can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0037] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "height", "upper", "lower", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like in the present application are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0038] In the description of the present application, it should be understood that the terms "first", "second" in the present application are only used for description purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features.

[0039] Example 1

[0040] Reference Figures 1-8The battery 100 provided in the embodiment includes a shell 1 and a cover plate 2, wherein the shell 1 has a first end 1a and a second end 1b arranged oppositely in a length direction, the shell 1 is provided with an opening 3 at the first end 1a, and the shell 1 is provided with a containing cavity 1c, the containing cavity 1c is communicated with the external environment through the opening 3, and the cover plate 2 is connected to the opening 3 to isolate the containing cavity 1c from the external environment.

[0041] In the embodiment, the shell 1 has a first direction X, a second direction Y and a third direction Z perpendicular to each other, wherein the direction in which the first end 1a and the second end 1b are located is the first direction X of the shell 1, that is, the length direction; the direction in which the long side of the opening 3 is located is the second direction Y of the shell 1, that is, the left-right direction, and the direction in which the short side of the opening 3 is located is the third direction Z of the shell 1, that is, the front-back direction.

[0042] The containing cavity 1c is provided with an electric core 4, and the electric core 4 includes a diaphragm 4a and a plurality of electrode sheets 4b, wherein the plurality of electrode sheets 4b are stacked to form a stacked structure, and the diaphragm 4a is arranged between adjacent two electrode sheets 4b and covers the outside of the stacked structure.

[0043] It can be understood that the electrode sheet 4b of the battery 100 usually includes two kinds of electrode sheets with opposite polarities, that is, a positive electrode sheet 4b1 and a negative electrode sheet 4b2, and the electrode assembly of the battery 100 works by moving metal ions between the positive electrode sheet 4b1 and the negative electrode sheet 4b2. The cycle process of the electric core is the process that the metal ions move from the positive electrode sheet 4b1 to the negative electrode sheet 4b2 and then move from the negative electrode sheet 4b2 to the positive electrode sheet 4b1. Figure 4 In the electric core 4 of the embodiment, the positive electrode sheet 4b1 and the negative electrode sheet 4b2 are alternately and sequentially stacked, that is, the positive electrode sheet 4b1 and the negative electrode sheet 4b2 are sequentially stacked in the order of negative electrode sheet 4b2-positive electrode sheet 4b1-negative electrode sheet 4b2-positive electrode sheet 4b1-negative electrode sheet 4b2, thereby forming a stacked structure, and the negative electrode sheet 4b2 is located at the outermost layer of the stacked structure.

[0044] It should be noted that the electric core 4 of the embodiment 1 is a stacked sheet electric core. For example, in the case that the electric core 4 is a stacked sheet electric core, the plurality of electrode sheets 4b are stacked to form a non-continuous stacked structure, that is, any two adjacent positive electrode sheets 4b1 are non-continuous structures and / or any two adjacent negative electrode sheets 4b2 are non-continuous structures.

[0045] It can be understood that the shell 1 is used to encapsulate the electric core and electrolyte and the like. The shell 1 can be various shapes and various sizes, for example, a cuboid, a hexagonal prism and the like, and the shape of the shell 1 can be determined according to the specific shape and size of the electric core. The material of the shell 1 can be various, including but not limited to copper, iron, aluminum, stainless steel, aluminum alloy, plastic and the like.

[0046] In each of the battery cells 4, the separator 4a is arranged between two adjacent electrode sheets 4b and covers the outside of the stacked structure to cover the outermost electrode sheet 4b. Taking the jelly-roll battery cell as an example, during the assembly of the battery cell 4, the positive electrode sheet 4b1, the separator 4a, and the negative electrode sheet 4b2 are sequentially stacked, where the upper surface and the lower surface of the electrode sheet 4b are distinguished according to the stacking direction of the electrode sheet 4b, the separator 4a is arranged between the positive electrode sheet 4b1 and the negative electrode sheet 4b2 and covers the upper surface and the lower surface of the positive electrode sheet 4b1 and the negative electrode sheet 4b2, thereby separating the adjacent positive electrode sheet 4b1 and the negative electrode sheet 4b2 to avoid direct contact between the adjacent positive electrode sheet 4b1 and the negative electrode sheet 4b2, and the separator 4a is usually a continuous thin film that extends from the inside of the stacked structure to the outside of the stacked structure and covers the outside of the stacked structure, thereby separating the electrode sheet 4b from the shell 1.

[0047] It should be noted that the separator 4a of the battery 100 is usually a porous insulating material, and the main function is to separate the positive electrode sheet 4b1 and the negative electrode sheet 4b2 and allow lithium ions to pass through. The separator 4a usually has a tail end (i.e., the end position of the winding of the separator 4a), and the tail end is connected with the fixing member 5 to tension the separator 4a. For example, in some batteries 100, the tail end of the separator 4a is connected with an insulating tape as the fixing member 5, one end of the insulating tape is bonded to the tail end of the separator 4a, and the other end is bonded to another position of the separator 4a. By pulling the insulating tape, the separator 4a can be tensioned to tightly cover the stacked structure.

[0048] Affected by the covering method of the separator 4a, the specification size of the separator 4a, and the specification size of the battery cell 4, the tail end of the separator 4a of different battery cells 4 can be distributed on different sides of the battery cell 4. For example, in the battery 100 of the present embodiment 1, the tail end of the separator 4a is fixed to the side of the battery cell 4 facing the first end la.

[0049] The insulating film 6 is usually arranged between the battery cell 4 and the shell 1 to separate the battery 100 group from the shell 1 and ensure the safety, reliability, and performance stability of the battery 100. Referring to Figure 4 Taking the jelly-roll battery cell as an example, the insulating film 6 covers the side of the battery cell 4 facing the second end lb, and the insulating film 6 extends towards the first end la to cover the outer circumferential side of the battery cell 4, thereby isolating the battery cell 4 from the shell 1; and the insulating film 6 is provided with a notch 6a facing the cover plate 2 to avoid the side of the battery cell 4 provided with the tail end, so that the insulating film 6 is arranged outside the side provided with the tail end and does not enter the side provided with the tail end, so as not to affect the connection of the battery cell 4 and the pole of the cover plate 2.

[0050] It can be understood that the separator 4a and the insulating film 6 are both arranged in the accommodation cavity lc, and the cooperation between the two will affect the assembly of the battery cell 4 in the shell 1, and further affect the performance of the battery 100.

[0051] In some batteries 100, the matching between the insulation film 6 and the separator 4a can be adjusted so that they match each other. For example, in the first direction X, taking the electrode tab 4b at the outermost layer and closest to the second end 1b as a reference electrode tab, the distance from the outer edge of the reference electrode tab toward the second end 1b to the outer edge of the electrode core 4 toward the second end 1b is L, the thickness of the insulation film 6 is D1, the elastic modulus of the separator 4a is E, and the above parameters satisfy:

[0052] 250≤(D1×E) / L≤5000. (1)

[0053] For example, the ratio of the distance L from the outer edge of the reference electrode tab toward the second end 1b to the outer edge of the electrode core 4 toward the second end 1b, the thickness D1 of the insulation film 6, and the elastic modulus E of the separator 4a can be one of 250, 350, 450, 550, 650, 750, 850, 950, 1000, 1500, 2000, 2500, 3000, 3500, 4000, 4500, and 5000 based on the relationship (1).

[0054] It can be understood that the distance L from the outer edge of the reference electrode tab toward the second end 1b to the outer edge of the electrode core 4 toward the second end 1b, the thickness D1 of the insulation film 6, and the elastic modulus E of the separator 4a reflect the matching structure of the insulation film 6 and the separator 4a. If the ratio of the distance L from the outer edge of the reference electrode tab toward the second end 1b to the outer edge of the electrode core 4 toward the second end 1b, the thickness D1 of the insulation film 6, and the elastic modulus E of the separator 4a is too small based on the relationship (1), the insulation film 6 is prone to be welded through and melted during the welding of the shell 1 and the cover plate 2. If the ratio of the distance L from the outer edge of the reference electrode tab toward the second end 1b to the outer edge of the electrode core 4 toward the second end 1b, the thickness D1 of the insulation film 6, and the elastic modulus E of the separator 4a is too large based on the relationship (1), the gap between the insulation film 6 and the cover plate 2 is prone to be too large, which affects the insulation performance of the battery 100. When the distance L from the outer edge of the reference electrode tab toward the second end 1b to the outer edge of the electrode core 4 toward the second end 1b, the thickness D1 of the insulation film 6, and the elastic modulus E of the separator 4a satisfy the above relationship (1), the insulation film 6, the separator 4a, and the electrode tab 4b can be matched, so that the insulation film 6 and the cover plate 2 form a matching fit, and the gap between the insulation film 6 and the cover plate 2 is within a proper range. In this way, the insulation performance between the electrode core 4 and the shell 1 can be ensured, and during the welding of the cover plate 2 and the shell 1, the gap between the insulation film 6 and the cover plate 2 can avoid the phenomenon that the insulation film 6 is welded through and melted due to the small gap between the insulation film 6 and the cover plate 2.

[0055] It should be noted that the outermost electrode sheet 4b refers to the electrode sheet 4b that is located at the outermost side in the stacking direction of the electrode sheet 4b in the stacked structure. Referring to Figure 4 In the case where the stacked structure of the battery cell 4 is stacked along the third direction Z, the electrode sheet 4b located at the outermost layer and close to the second end 1b is the negative electrode sheet 4b2 located at the frontmost side and the negative electrode sheet 4b2 located at the rearmost side. Referring to Figure 8 In the case where the stacked structure of the battery cell 4 is stacked along the first direction X, the electrode sheet 4b located at the outermost layer and close to the second end 1b is the negative electrode sheet 4b2 located at the lowermost side.

[0056] It should be noted that the distance L from the side of the reference electrode sheet facing the second end 1b to the side of the corresponding battery cell 4 facing the second end 1b is the thickness of the separator 4a arranged on the side of the reference electrode sheet facing the second end 1b. Of course, in different battery 100 structures, the separator 4a can be a single-layer structure or a multi-layer structure, so the thickness of the separator 4a is usually the product of the thickness of a single-layer separator and the number of layers of the separator.

[0057] In order to verify that the structural parameters of the battery 100 provided in this embodiment 1 satisfy the above relationship (1), that is, the distance L from the outer edge of the reference electrode sheet facing the second end 1b to the outer edge of the battery cell 4 facing the second end 1b, the thickness D1 of the insulating film 6, and the elastic modulus E of the separator 4a match, the insulating film 6 of the battery 100 of this embodiment 1 can ensure good insulation performance and is not easily melted due to welding compared with other batteries 100. This embodiment 1 conducted 9 groups of tests, as shown in the following Table 1:

[0058] In Table 1, test examples 1 to 9 are based on the structure of the battery 100 of this embodiment 1, that is, the distance L, the thickness D1 of the insulating film 6, and the elastic modulus E of the separator 4a of the battery 100 of test examples 1 to 15 satisfy the matching relationship of the above relationship (1). Comparative examples 1 to 4 are other battery structures, that is, the distance L, the thickness D1 of the insulating film, and the elastic modulus E of the separator of comparative examples 1 to 4 do not satisfy the matching relationship of the above relationship (1).

[0059] The separator welding penetration test method is as follows: according to Table 1, different thicknesses of insulating films and different elastic moduli of separators are selected to assemble into battery cells. Subsequently, the battery cells are placed in a shell, and a laser welding technology is used to weld the cover plate and the shell together. During the welding process, the welding power is maintained at 2000W, and the welding speed is set to 50mm / s. After the welding operation is completed, the battery is disassembled, and it is checked whether the insulating film is penetrated by welding.

[0060] The insulation performance test method is: according to table 1, different thickness of the insulating film and different elastic modulus of the diaphragm are selected to assemble into the battery cell. Then, the battery cell is placed in the shell, the cover plate is sealed with the shell by laser welding technology, the electrolyte is injected, the formation treatment is carried out, and finally the battery is made. The positive material of the battery is lithium iron phosphate. First, the battery is charged to 3.25V at 1 / 3C current, and then discharged to 2.5V at 1 / 3C current after standing for 10 minutes. After standing for 1 hour, the open circuit voltage is measured and recorded, marked as V1. Then, repeat the above charging and discharging process, stand for 10 minutes, and then perform 500 cycles. After completing the cycle, stand for 50 minutes, and then measure and record the open circuit voltage again, marked as V2. Finally, the voltage difference of the battery after cycle is calculated according to the formula ΔV = V1-V2.

[0061] Table 1

[0062]

[0063]

[0064] As can be seen from table 1, when the distance L from the outer edge of the reference electrode sheet facing the second end 1b to the outer edge of the battery cell 4 facing the second end 1b, the thickness D1 of the insulating film 6, and the elastic modulus E of the diaphragm 4a satisfy the matching relationship of the above formula (1), the insulating film 6 not only ensures the excellent insulation performance between the battery cell 4 and the shell 1, but also will not be melted due to welding during the welding process of the cover plate 2 and the shell 1. When the distance L from the outer edge of the reference electrode sheet facing the second end 1b to the outer edge of the battery cell 4 facing the second end 1b, the thickness D1 of the insulating film 6, and the elastic modulus E of the diaphragm 4a do not satisfy the matching relationship of the above formula (1), the battery will have problems of melting of the insulating film 6 or insufficient insulation performance between the battery cell 1 and the shell 1.

[0065] For example, in this embodiment 1, the distance L from the outer edge of the reference electrode sheet facing the second end 1b to the outer edge of the battery cell 4 facing the second end 1b can satisfy: 3≤L≤200μm, for example, the distance L can be one of 3μm, 4μm, 5μm, 6μm, 7μm, 8μm, 9μm, 10μm, 20μm, 30μm, 40μm, 50μm, 60μm, 70μm, 80μm, 90μm, 100μm, 110μm, 120μm, 130μm, 140μm, 150μm, 160μm, 170μm, 180μm, 190μm, 200μm.

[0066] Exemplarily, in the present embodiment 1, the insulation film thickness D1 can satisfy: 50≤D1≤150μm, for example, the insulation film thickness D1 can be one of 50μm, 60μm, 70μm, 80μm, 90μm, 100μm, 110μm, 120μm, 130μm, 140μm, 150μm.

[0067] Exemplarily, in the present embodiment 1, the elastic modulus E of the diaphragm 4a can satisfy: 200≤E≤2000Mpa, for example, the elastic modulus E of the diaphragm 4a can be one of 200Mpa, 300Mpa, 400Mpa, 500Mpa, 600Mpa, 700Mpa, 800Mpa, 900Mpa, 1000Mpa, 1100Mpa, 1200Mpa, 1300Mpa, 1400Mpa, 1500Mpa, 1600Mpa, 1700Mpa, 1800Mpa, 1900Mpa, 2000Mpa.

[0068] It can be understood that a large amount of heat will be generated when the cover plate 2 is welded, and if the insulation film 6 is too close to the cover plate 2, the heat generated by the welding of the cover plate 2 is easy to be transmitted to the insulation film 6, causing the insulation film 6 to shrink due to heat, which is easy to cause the battery cell to be exposed from the insulation film 6, resulting in the risk of the battery cell being overlapped with the shell 1, so there is usually a certain interval distance between the insulation film 6 and the cover plate 2, that is, there is a certain interval distance between the side of the insulation film 6 facing the cover plate 2 and the side of the cover plate 2 facing the battery cell 4 in the first direction X, and the present embodiment 1 defines this interval distance as the shortest vertical distance h1 between the insulation film 8 and the cover plate 2 in the first direction X. Exemplarily, in some battery 100, the shortest vertical distance h1 between the insulation film 8 and the cover plate 2 in the first direction X can satisfy: 0.5≤h1≤5mm, for example, h1 can be one of 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm.

[0069] Of course, in the case that the interval distance between the insulation film 6 and the cover plate 2 satisfies h1, the interval distance between the insulation film 6 and the cover plate 2 is more suitable for the battery cell 4, so in this case, taking the electrode sheet 4b in the outermost layer and close to the second end 1b as a reference electrode sheet 4b, the distance L from the outer edge of the reference electrode sheet 4b facing the second end 1b to the outer edge of the battery cell 4 facing the second end 1b, the thickness D1 of the insulation film 6, and the elastic modulus E of the diaphragm 4a can also satisfy:

[0070] 250≤(D1×E) / L≤4000……(2)

[0071] Exemplarily, the ratio of the distance L from the outer edge of the reference electrode sheet towards the second end 1b to the outer edge of the battery core 4 towards the second end 1b, the thickness D1 of the insulating film 6, and the elastic modulus E of the separator 4a can be one of 250, 350, 450, 550, 650, 750, 850, 950, 1000, 1500, 2000, 2500, 3000, 3500, 4000 based on the ratio of the relationship (2).

[0072] It should be noted that the battery core 4 arranged in the accommodating cavity 1c has various arrangements, for example, the stacking direction of the plurality of electrode sheets 4b can be parallel to the first direction X. Referring to Figures 1-6 、 Figure 8 In the case where the stacking direction of the plurality of electrode sheets 4b is parallel to the first direction X, the parallel stacking of the plurality of electrode sheets 4b can make the insulating film 6 and the separator 4a more easily keep flat during the stacking process, so that the battery core 4 can be more conveniently arranged in the accommodating cavity 1c, and the degree of folding of the separator close to the second end 1b is reduced. Therefore, in this case, the distance L from the outer edge of the reference electrode sheet towards the second end 1b to the outer edge of the battery core 4 towards the second end 1b, the thickness D1 of the insulating film 6, and the elastic modulus E of the separator 4a can also satisfy:

[0073] 250≤(D1×E) / L≤3000. ……(3)

[0074] Exemplarily, the ratio of the distance L from the outer edge of the reference electrode sheet towards the second end 1b to the outer edge of the battery core 4 towards the second end 1b, the thickness D1 of the insulating film 6, and the elastic modulus E of the separator 4a can be one of 250, 350, 450, 550, 650, 750, 850, 950, 1000, 1500, 2000, 2500, 3000 based on the ratio of the relationship (3).

[0075] Of course, the stacking direction of the plurality of electrode sheets 4b can also be perpendicular to the first direction X. Referring to Figures 1-6 、 Figure 7 In the case where the stacking direction of the plurality of electrode sheets 4b is perpendicular to the first direction X, the perpendicular stacking of the plurality of electrode sheets 4b can make the insulating film 6 and the separator 4a more evenly stressed during the stacking process, reduce the local stress concentration of the insulating film 6 and the separator 4a, and the shell 1 can reduce the size in the second direction Y or the third direction Z, thereby reducing the welding length of the shell 1 and the cover plate 2, and further improving the welding yield of the shell 1 and the cover plate 2. Therefore, in this case, the distance L from the outer edge of the reference electrode sheet towards the second end 1b to the outer edge of the battery core 4 towards the second end 1b, the thickness D1 of the insulating film 6, and the elastic modulus E of the separator 4a can also satisfy:

[0076] 1200≤(D1×E) / L≤5000. (4)

[0077] Exemplarily, the ratio of the distance L from the outer edge of the reference electrode tab towards the second end 1b to the outer edge of the electric core 4 towards the second end 1b, the thickness D1 of the insulating film 6, and the elastic modulus E of the diaphragm 4a can be one of 1200, 1300, 1400, 1500, 2000, 2500, 3000, 3500, 4000, 4500, 5000 based on the ratio of the relationship formula (4).

[0078] Reference Figures 1-8 In the partial battery 100, the insulating piece 7 is arranged between the electric core 4 and the cover plate 2, for isolating the electric connection components in the shell 1 from the cover plate 2, to reduce the risk of short circuit. The material of the insulating piece 7 generally includes plastic, rubber, etc. With the change of the thickness of the insulating piece 7, its insulation performance will be affected accordingly. As an example of the present embodiment 1, the thickness of the insulating piece 7 is D2, and the thickness D2 of the insulating piece 7 can satisfy: 0.5≤D2≤5mm. Exemplarily, D2 can be one of 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm.

[0079] The thickness D2 of the insulating piece 7 satisfies: 0.5≤D2≤5mm, which can ensure the insulation performance of the insulating piece 7, thereby improving the insulation effect between the electric core 4 and the cover plate 2, and increasing the interval distance between the insulating film 6 and the cover plate 2. In this case, taking the electrode tab 4b in the outermost layer and close to the second end 1b as the reference electrode tab 4b, the distance L from the outer edge of the reference electrode tab towards the second end 1b to the outer edge of the electric core 4 towards the second end 1b, the thickness D1 of the insulating film 6, and the elastic modulus E of the diaphragm 4a can also satisfy:

[0080] 250≤(D1×E) / L≤2500. (5)

[0081] Exemplarily, the ratio of the distance L from the outer edge of the reference electrode tab towards the second end 1b to the outer edge of the electric core 4 towards the second end 1b, the thickness D1 of the insulating film 6, and the elastic modulus E of the diaphragm 4a can be one of 250, 350, 450, 550, 650, 750, 850, 950, 1000, 1500, 2000, 2500 based on the ratio of the relationship formula (5).

[0082] Reference Figures 1-8In some of the batteries 100, a barrier 8 is further arranged between the cell 4 and the shell 1 to isolate the shell 1 from the cell 4 and reduce the risk of short circuit. The barrier 8 is arranged between the cell 4 and the shell 1 on the side of the cell 4 facing the second end 1b, and the barrier 8 can be made of plastic, rubber, or the like.

[0083] It can be understood that the insulation performance of the barrier 8 will be affected as the thickness of the barrier 8 changes. As an example of the present embodiment 1, the thickness of the barrier 8 is D3, and the thickness D3 of the barrier 8 can satisfy: 0.5≤D3≤3mm. For example, D3 can be one of 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.5mm, 2mm, 2.5mm, and 3mm.

[0084] The thickness D3 of the barrier 8 satisfies: 0.5≤D3≤3mm, which can ensure the insulation performance of the barrier 8 and ensure that the barrier 8 can support the cell 4 and reduce the influence of the R angle of the shell 1 on the cell 4. In this case, the distance L from the outer edge of the reference electrode sheet 4b facing the second end 1b to the outer edge of the cell 4 facing the second end 1b, the thickness D1 of the insulating film 6, and the elastic modulus E of the separator 4a can also satisfy:

[0085] 1800≤(D1×E) / L≤2500. ……(6)

[0086] For example, the ratio of the distance L from the outer edge of the reference electrode sheet 4b facing the second end 1b to the outer edge of the cell 4 facing the second end 1b, the thickness D1 of the insulating film 6, and the elastic modulus E of the separator 4a based on the relationship (6) can be one of 1800, 1900, 2000, 2100, 2200, 2300, 2400, and 2500.

[0087] Based on the above-mentioned battery 100, the present embodiment 1 further provides a battery module, which includes at least two of any of the above-mentioned batteries 100, and the two batteries are connected in series or in parallel.

[0088] Based on the above-mentioned battery module, the present embodiment 1 further provides a battery pack, which includes a housing and at least two of the above-mentioned battery modules, and the two battery modules are arranged in the housing and electrically connected.

[0089] Embodiment 2

[0090] Reference Figures 9-16The battery 100 of the embodiment 2 comprises a shell 1 and a cover plate 2, wherein the shell 1 has a first end 1a and a second end 1b arranged oppositely in a length direction, the shell 1 is provided with an opening 3 at the first end 1a, and the shell 1 is provided with a containing cavity 1c.

[0091] In the embodiment 2, the shell 1 has a first direction X, a second direction Y and a third direction Z perpendicular to each other, wherein the first direction X of the shell 1 is the length direction with the first end 1a and the second end 1b; the second direction Y of the shell 1 is the left-right direction with the long side of the opening 3; and the third direction Z of the shell 1 is the front-back direction with the short side of the opening 3.

[0092] The containing cavity 1c is provided with an electrode assembly. In the embodiment 2, the electrode assembly comprises two electrode cores 4, each of which comprises a diaphragm 4a and a plurality of electrode plates 4b, wherein the plurality of electrode plates 4b are stacked to form a stacked structure, and adjacent two electrode cores are arranged along the stacking direction of the stacked structure.

[0093] It can be understood that the electrode plate 4b of the battery generally comprises two kinds of electrode plates with opposite polarities, i.e. positive electrode plate 4b1 and negative electrode plate 4b2, and the electrode assembly of the battery works by moving metal ions between the positive electrode plate 4b1 and the negative electrode plate 4b2. The cycle process of the electrode core is the process that the metal ions move from the positive electrode plate 4b1 to the negative electrode plate 4b2 and then move from the negative electrode plate 4b2 to the positive electrode plate 4b1. Figures 9-16 In the electrode core 4 of the embodiment 2, the positive electrode plate 4b1 and the negative electrode plate 4b2 are alternately and sequentially stacked, i.e. the positive electrode plate 4b1 and the negative electrode plate 4b2 are sequentially stacked in the order of negative electrode plate 4b2-positive electrode plate 4b1-negative electrode plate 4b2-positive electrode plate 4b1-negative electrode plate 4b2, thereby forming a stacked structure, and the negative electrode plate 4b2 is at the outermost layer of the stacked structure.

[0094] It should be noted that the electrode core 4 of the embodiment 2 is a stacked electrode core, and the shell 1 is used to package the electrode core and electrolyte and the like. The shell 1 can be various shapes and sizes, such as a cuboid, a hexagonal prism, etc., and the shape of the shell 1 can be determined according to the specific shape and size of the electrode core. The material of the shell 1 can be various, including but not limited to copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0095] In each of the battery cells 4, the separator 4a is arranged between two adjacent electrode sheets 4b and is wound on the outside of the stacked structure in the stacking direction of the electrode sheets 4b to cover the outermost electrode sheet 4b. Specifically, during the assembly of the battery 100, the positive electrode sheet 4b1, the separator 4a, and the negative electrode sheet 4b2 are sequentially stacked, with the upper and lower surfaces of the electrode sheets 4b distinguished in the stacking direction of the electrode sheets 4b, the separator 4a is arranged between the positive electrode sheet 4b1 and the negative electrode sheet 4b2 to cover the upper and lower surfaces of the positive electrode sheet 4b1 and the negative electrode sheet 4b2, thereby separating the adjacent positive electrode sheet 4b1 and negative electrode sheet 4b2 to prevent direct contact between the adjacent positive electrode sheet 4b1 and negative electrode sheet 4b2. In addition, the separator 4a is usually a continuous thin film that extends from the inside of the stacked structure to the outside of the stacked structure and covers the outside of the stacked structure, thereby separating the electrode sheets 4b from the housing 1.

[0096] It should be noted that the separator 4a of the battery is usually a porous insulating material, and its main function is to separate the positive electrode sheet 4b1 and the negative electrode sheet 4b2 and allow lithium ions to pass through. The end of the separator 4a (i.e., the end position of the winding of the separator 4a) usually needs to be connected to a fixing member 5 to tension the separator 4a. For example, in some batteries, the end of the separator 4a is connected to an insulating tape as the fixing member 5, one end of the insulating tape is bonded to the end of the separator 4a, and the other end is bonded to another position of the separator 4a. By pulling the insulating tape, the separator 4a can be tensioned to tightly cover the stacked structure.

[0097] An insulating film 6, such as an insulating film, is usually provided between the battery 100 and the housing 1 to separate the battery 100 and the housing 1 and ensure the safety, reliability, and performance stability of the battery. Referring to Figures 9-16 , the insulating film 6 covers the side of the two battery cells facing the second end 1b, and the insulating film 6 extends towards the first end 1a to cover the outer peripheral side of the two battery cells, thereby isolating the battery cells from the housing 1. In addition, the insulating film 6 is arranged outside the end side of the two battery cells facing the first end 1a and does not enter the end side of the two battery cells facing the first end 1a to avoid affecting the connection of the pole of the battery 100 to the cover plate 2.

[0098] It can be understood that the separator 4a of each battery cell of the battery 100 has its own end, and under the cooperation of the fixing member 5, the tension of the end of the separator 4a is usually better than that of other positions of the separator 4a. In this case, when the ends of the separators 4a of the two battery cells are arranged on different sides of the stacked structure, the flatness of the separators 4a on one side of the same battery 100 will differ. For this reason, refer to Figures 9-16In the case where the end of the separator 4a of the two battery cells is arranged on different sides of the stacked structure, and in the case where the end of the separator 4a of one battery cell is fixed to the side of the battery cell 4 facing the first end la, the battery 100 of the present embodiment 2, in the first direction X, takes the electrode sheet 4b that is the outermost layer and is close to the outer peripheral side of the case 1 as a reference electrode sheet, the distance from the outer edge of the reference electrode sheet facing the second end lb to the outer edge of the battery cell 4 facing the second end lb is L, the thickness of the insulating film 6 is D1, and the elastic modulus of the separator 4a is E, then the above parameters satisfy:

[0099] 250≤(D1×E) / L≤4000... (7)

[0100] For example, the ratio of the distance L from the outer edge of the reference electrode sheet facing the second end lb to the outer edge of the battery cell 4 facing the second end lb, the thickness D1 of the insulating film 6, and the elastic modulus E of the separator 4a based on the relationship (7) can be one of 250, 350, 450, 550, 650, 750, 850, 950, 1000, 1500, 2000, 2500, 3000, 3500, 4000, 4500, 5000.

[0101] It can be understood that the distance L from the outer edge of the reference electrode sheet facing the second end lb to the outer edge of the battery cell 4 facing the second end lb, the thickness D1 of the insulating film 6, and the elastic modulus E of the separator 4a reflect the matching structure of the insulating film 6 and the separator 4a. If the values of the distance L from the outer edge of the reference electrode sheet facing the second end lb to the outer edge of the battery cell 4 facing the second end lb, the thickness D1 of the insulating film 6, and the elastic modulus E of the separator 4a based on the relationship (7) are too small, the insulating film 6 is prone to be welded and melted during the welding process of the case 1 and the cover plate 2. If the values of the distance L from the outer edge of the reference electrode sheet facing the second end lb to the outer edge of the battery cell 4 facing the second end lb, the thickness D1 of the insulating film 6, and the elastic modulus E of the separator 4a based on the relationship (7) are too large, the gap between the insulating film 6 and the cover plate 2 is too large, which affects the insulation performance of the battery. When the distance L from the outer edge of the reference electrode sheet facing the second end lb to the outer edge of the battery cell 4 facing the second end lb, the thickness D1 of the insulating film 6, and the elastic modulus E of the separator 4a satisfy the above relationship (7), the insulating film 6, the separator 4a, and the electrode sheet 4b can be matched, so that the insulating film 6 and the cover plate 2 are matched and matched, and the distance between the insulating film 6 and the cover plate 2 is within a suitable interval. In this way, the insulation performance between the battery cell 4 and the case 1 can be ensured, and during the welding of the cover plate 2 and the case 1, the distance between the insulating film 6 and the cover plate 2 can avoid the phenomenon that the insulating film 6 is welded and melted during the welding process due to the small distance between the insulating film 6 and the cover plate 2.

[0102] It should be noted that in the battery 100, two battery cells 4 are arranged along the stacking direction of the stacking structure, so in the battery 100 of the embodiment 2, the electrode tab 4b at the outermost layer and close to the outer peripheral side of the shell 1 is: in the battery cell 4 at the front side, the negative electrode tab 4b2 at the frontmost side, and in the battery cell 4 at the rear side, the negative electrode tab 4b2 at the rearmost side.

[0103] It should be noted that the distance L from the outer edge of the reference electrode tab towards the second end 1b to the outer edge of the battery cell 4 towards the second end 1b is the thickness of the separator 4a arranged on the side surface of the reference electrode tab 4b towards the second end 1b. Of course, in different battery structures, the separator 4a can be a single-layer structure or a multi-layer structure, so the thickness of the separator 4a is usually the product of the thickness of a single-layer separator and the number of layers of the separator.

[0104] It should be noted that in the case that the end of the separator 4a of one battery cell is fixed to the side of the battery cell 4 towards the first end 1a, there are multiple possibilities for the end of the separator 4a of the other battery cell of the battery 100. For example, the end of the separator 4a of one battery cell 4 is arranged on the side of the battery cell towards the second end 1b, or in the arrangement direction of the two battery cells 4, the end of the separator 4a of one battery cell 4 is arranged on any side of the battery cell 4 in the arrangement direction, i.e. the end of the separator 4a of one battery cell 4 is arranged on the opposite side of the adjacent two battery cells, or the end of the separator 4a of one battery cell 4 is arranged on the side of the battery cell towards the outer peripheral side of the shell 1. In the following, the embodiment 2 will be described for the two arrangement modes respectively.

[0105] Reference Figures 9-16 , in Figure 12 The battery cell group shown in the figure, the battery cell 4 at the front side is the first battery cell, and the battery cell 4 at the rear side is the second battery cell. In the case that the end of the separator 4a of one battery cell is arranged on the side of the battery cell towards the second end 1b, i.e. the end of the separator 4a of the first battery cell is arranged on the lower side of the stacking structure, and the end of the separator 4a of the second battery cell is arranged on the upper side of the stacking structure, at this time, the fixing member 5 of the second battery cell is also arranged on the upper side, the separator 4a is relatively tight on the upper side of the second battery cell, and relatively loose on the lower side, the rear side and the front side of the second battery cell, and the insulating film 6 covers the lower side and the rear side of the second battery cell, in this case, in the first direction X, the electrode tab 4b at the outermost layer and close to the outer peripheral side of the shell 1 is the reference electrode tab, the distance from the outer edge of the reference electrode tab towards the second end 1b to the outer edge of the battery cell 4 towards the second end 1b is L, the thickness of the insulating film 6 is D1, and the elastic modulus of the separator 4a is E, then the above parameters satisfy:

[0106] 250≤(D1×E) / L≤3000. ……(8)

[0107] Exemplarily, the ratio of the distance L from the outer edge of the reference electrode tab towards the second end 1b to the outer edge of the electrode core 4 towards the second end 1b, the thickness D1 of the insulating film 6, and the elastic modulus E of the separator 4a can be one of 250, 350, 450, 550, 650, 750, 850, 950, 1000, 1500, 2000, 2500, 3000 based on the ratio of the relationship (8).

[0108] Reference Figures 9-16 In the case where the end of the separator 4a of one electrode core 4 is arranged on either side of the electrode core 4 in the arrangement direction, there are cases where the end of the separator 4a of one electrode core is arranged on the side of the electrode core towards the outer periphery of the case 1, i.e., the end of the separator 4a of the first electrode core is arranged on the lower side of the stacked structure, and the end of the separator 4a of the second electrode core is arranged on the rear side of the stacked structure, and cases where the end of the separator 4a of one electrode core is arranged on the opposite side of the adjacent two electrode cores, i.e., the end of the separator 4a of the first electrode core is arranged on the lower side of the stacked structure, and the end of the separator 4a of the second electrode core is arranged on the front side of the stacked structure.

[0109] In both cases, the fixing member 5 of the second electrode core is arranged on the rear side or the front side, and accordingly, the separator 4a is more compact on the rear side or the front side of the second electrode core and is looser on the other side of the second electrode core, and the insulating film 6 covers the lower side and the rear side of the second electrode core, so that in the cooperation of the second electrode core and the insulating film 6, the constraint force of the separator 4a on one side of the second electrode core is poor, and the insulating film 6 is more easily bonded to the second electrode core. In this way, in the first direction X, taking the electrode tab 4b in the outermost layer and close to the outer periphery of the case 1 as the reference electrode tab, the distance from the outer edge of the reference electrode tab towards the second end 1b to the outer edge of the electrode core 4 is L, the thickness of the insulating film 6 is D1, and the elastic modulus of the separator 4a is E, and the above parameters satisfy:

[0110] 250≤(D1×E) / L≤3000. ……(9)

[0111] Exemplarily, the ratio of the distance L from the outer edge of the reference electrode tab towards the second end 1b to the outer edge of the electrode core 4 towards the second end 1b, the thickness D1 of the insulating film 6, and the elastic modulus E of the separator 4a can be one of 250, 350, 450, 550, 650, 750, 850, 950, 1000, 1500, 2000, 2500, 3000 based on the ratio of the relationship (9).

[0112] It should be noted that, in the battery 100 of the present embodiment 2, two adjacent battery cells are arranged along the stacking direction of the stacked structure, i.e., two adjacent battery cells are arranged along the front-rear direction, and the separator 4a of the present embodiment 2 is arranged between two adjacent electrode sheets 4b and is wound outside the stacked structure along the stacking direction of the electrode sheets 4b, i.e., the separator 4a of the present embodiment 2 is wound outside the stacked structure along the front-rear direction. Therefore, even in the case where the end of the separator 4a of a battery cell is arranged on the side surface of the battery cell facing the outer circumferential side of the shell 1, the end of the separator 4a of the battery cell will only be arranged toward the rear side of the shell 1, and will not be arranged toward the left side or the right side of the shell 1. Of course, in other battery structures, if two adjacent battery cells are arranged along the left-right direction, the end of the separator 4a of the corresponding battery cell will be arranged toward the left side or the right side of the shell 1, and will not be arranged toward the front side or the rear side of the shell 1.

[0113] It can be understood that the thickness of the separator 4a will affect its rigidity. The thicker the separator 4a, the higher the rigidity, the greater the resilience when the separator 4a is bent, and it is difficult to tightly fit the electrode sheet 4b. In addition, when the thickness of the separator 4a is large, the separator 4a is prone to wrinkles during winding, resulting in a loose winding structure. Of course, the thickness of the separator 4a will also increase its insulation performance to avoid the overlap of the battery cell 4 and the shell 1. Considering the insulation cooperation between the shell 1 and the battery cell 4, the thickness of the separator 4a wound on the stacked structure needs to be controlled. For example, in the arrangement direction of the two battery cells 4, at least one battery cell 4 satisfies: the distance between the outer edge of the electrode sheet 4b close to the shell 1 and the outer edge of the corresponding battery cell 4 is S1, and the distance between the outer edge of the electrode sheet 4b close to the adjacent side of the two battery cells 4 and the outer edge of the corresponding battery cell 4 is S2, and S1>S2, i.e., the thickness of the separator 4a on the front side of the first battery cell is greater than the thickness of the separator 4a on the rear side of the first battery cell, and the thickness of the separator 4a on the rear side of the second battery cell is greater than the thickness of the separator 4a on the front side of the second battery cell, to ensure good insulation performance between the shell 1 and the battery cell 4.

[0114] Of course, in the above case, the distance S1 between the outer edge of the electrode sheet 4b close to the shell 1 and the outer edge of the corresponding battery cell 4, and the distance S2 between the outer edge of the electrode sheet 4b close to the adjacent side of the two battery cells 4 and the outer edge of the corresponding battery cell 4 will affect the assembly cooperation of the separator 4a and the electrode sheet 4b, so the mutual cooperation between the insulating film 6 and the separator 4a needs to be adjusted accordingly. For example, in the first direction X, taking the electrode sheet 4b in the outermost layer and close to the outer circumferential side of the shell 1 as a reference electrode sheet, the distance from the outer edge of the reference electrode sheet facing the second end 1b to the outer edge of the battery cell 4 facing the second end 1b is L, the thickness of the insulating film 6 is D1, and the elastic modulus of the separator 4a is E. The above parameters can satisfy:

[0115] 800≤(D1×E) / L≤3500. (10)

[0116] For example, the ratio of the distance L from the outer edge of the reference electrode tab 4b toward the second end 1b to the outer edge of the electrode core 4 toward the second end 1b, the thickness D1 of the insulating film 6, and the elastic modulus E of the separator 4a can be one of 800, 850, 900, 950, 1000, 1500, 2000, 2500, 3000, and 3500 based on the ratio of the relationship (10).

[0117] In summary, the battery 100 of the present embodiment can match the insulating film 6, the separator 4a, and the electrode tab 4b by adjusting the distance L from the outer edge of the reference electrode tab 4b toward the second end 1b to the outer edge of the electrode core 4 toward the second end 1b, the thickness D1 of the insulating film 6, and the elastic modulus E of the separator 4a, so that the insulating film 6 and the cover plate 2 form a matching fit, and the spacing distance between the insulating film 6 and the cover plate 2 is within the appropriate interval. In this way, the insulating performance between the electrode core 4 and the shell 1 can be ensured, and when the cover plate 2 and the shell 1 are welded, the spacing distance between the insulating film 6 and the cover plate 2 can avoid the phenomenon that the insulating film 6 is melted and welded through during the welding process due to the small spacing distance between the insulating film 6 and the cover plate 2. The battery module and the battery pack of the present application apply the above battery 100 and have the beneficial effects of the above battery 100.

[0118] The above description is only the preferred embodiments of the present application, and it should be noted that those skilled in the art can make several improvements and replacements without departing from the technical principles of the present application, and these improvements and replacements should also be considered as the protection scope of the present application.

Claims

1. A battery, characterized in that: include: a housing having a first end and a second end opposite to each other in a first direction, wherein the housing is provided with a receiving cavity, and the first end is provided with an opening connecting the receiving cavity with the external environment; a cover plate connected to the opening to isolate the accommodating cavity from the external environment; A battery cell, comprising a diaphragm and a plurality of electrode sheets, wherein the plurality of electrode sheets are stacked to form a non-continuous stacked structure; the diaphragm is disposed between two adjacent electrode sheets and covers the outside of the stacked structure; and the diaphragm has a tail end, which is fixed to the side of the battery cell facing the first end; the number of the battery cells is at least two, two of the battery cells are disposed in the accommodating cavity, and two adjacent battery cells are arranged in a direction perpendicular to the first direction; and the tail ends of the two battery cells are disposed on different sides of the stacked structure, and the tail end of at least one of the battery cells is fixed to the side of the battery cell facing the first end; an insulating film covering the outer side of the battery cell and extending toward the first end, wherein the insulating film is provided with a notch toward the cover plate to avoid the side of the battery cell provided with the tail end; and In the first direction, the electrode sheet in the outermost layer and close to the second end is used as the reference electrode sheet, the distance from the outer edge of the reference electrode sheet facing the second end to the outer edge of the battery cell facing the second end is L, the thickness of the insulating film is D1, and the elastic modulus of the diaphragm is E, then the above parameters satisfy: 250≤(D1×E) / L≤4000, Furthermore, the distance L satisfies: 3≤L≤200 μm; and / or the thickness D1 of the insulating film satisfies: 50≤D1≤150 μm; and / or the elastic modulus E of the diaphragm satisfies: 200≤E≤2000 MPa.

2. The battery according to claim 1, characterized in that In the first direction, the shortest vertical distance between the insulating film and the cover plate is h1, 0.5≤h1≤5mm, and the distance L, the thickness D1 of the insulating film, and the elastic modulus E of the diaphragm satisfy: 250≤(D1×E) / L≤4000.

3. The battery according to claim 1, characterized in that The stacking direction of the plurality of electrode sheets is perpendicular to the first direction, and the distance L, the thickness D1 of the insulating film, and the elastic modulus E of the diaphragm satisfy: 250≤(D1×E) / L≤3000.

4. The battery according to claim 1, characterized in that The stacking direction of the plurality of electrode sheets is parallel to the first direction, and the distance L, the thickness D1 of the insulating film, and the elastic modulus E of the diaphragm satisfy: 1200≤(D1×E) / L≤5000.

5. The battery according to claim 1, characterized in that An insulating member is provided between the battery cell and the cover plate, and the thickness of the insulating member is D2, and the thickness D2 of the insulating member satisfies: 0.5≤D2≤5mm, and the distance L, the thickness D1 of the insulating film, and the elastic modulus E of the diaphragm satisfy: 250≤(D1×E) / L≤2500.

6. The battery according to claim 1, characterized in that The battery further comprises: A barrier is provided between the side of the battery cell facing the second end and the shell, and the thickness of the barrier is D3, and the thickness D3 of the barrier satisfies: 0.5≤D3≤3mm, and the distance L, the thickness D1 of the insulating film, and the elastic modulus E of the diaphragm satisfy: 1800≤(D1×E) / L≤2500.

7. The battery according to claim 1, characterized in that The tail end of one of the battery cells is arranged on the side of the battery cell facing the second end, and the distance L, the thickness D1 of the insulating film, and the elastic modulus E of the diaphragm satisfy: 250≤(D1×E) / L≤3000.

8. The battery according to claim 1, characterized in that In the arrangement direction of the two battery cells, the tail end of one battery cell is arranged on any side of the battery cell in the arrangement direction, and the distance L, the thickness D1 of the insulating film, and the elastic modulus E of the diaphragm satisfy: 250≤(D1×E) / L≤3500.

9. The battery according to claim 1, characterized in that In the arrangement direction of the two battery cells, at least one of the battery cells meets the following requirements: The distance between the outer edge of the electrode sheet close to one side of the shell and the outer edge of the corresponding battery cell is S1, the distance between the outer edge of the electrode sheet close to the adjacent side of two battery cells and the outer edge of the corresponding battery cell is S2, and S1>S2; and The distance L, the insulating film thickness D1, and the diaphragm elastic modulus E satisfy: 800≤(D1×E) / L≤3500.

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