Battery

Abstract

Battery characterized in that it comprises the following: a housing body having a first end and a second end arranged opposite each other in a first direction, the housing body having a receiving chamber and the first end being provided with an opening connecting the receiving chamber to the outside environment; a cover plate connected to the opening to isolate the recording chamber from the outside environment; a cell comprising a separator and several electrode sheets, wherein the several electrode sheets are arranged stacked on top of each other to form a non-continuous stacked structure, wherein the separator is arranged between two adjacent electrode sheets and encloses them to the outside of the stacked structure, wherein the separator has an end piece, while the end piece is attached to the side of the cell facing the first end, wherein the number of cells is at least two, and the two cells are arranged in the receiving chamber, wherein the two adjacent cells are arranged in a direction perpendicular to the first direction, and the end pieces of the two cells are arranged on opposite sides of the stacked structure, and wherein the end piece of at least one of the cells is attached to the side of the cell facing the first end; an insulating film that encloses the outside of the cell and extends towards the first end, the insulating film being provided with a notch facing the cover plate to accommodate the side of the cell where the end piece is located; and in the first direction, wherein the electrode sheet located in the outermost layer and near the second end serves as a reference electrode sheet, the distance between the outer edge of the reference electrode sheet facing the second end and the outer edge of the cell facing the second end is L, the thickness of the insulating film is D1, the elastic modulus of the separator is E, and the above parameters satisfy the following condition: 250 ≤ (D 1 × E ) / L ≤ 4000, where the distance L satisfies the condition: 3 ≤ L ≤ 200 µm, and / or the thickness D1 of the insulating film satisfies the condition: 50 ≤ D1 ≤ 150 µm, and / or the elastic modulus E of the separator satisfies the condition: 200 ≤ E ≤ 2000 MPa.

Description

[0001] The present application is a divisional application of the patent application with the application number “202510408549.2”, the filing date “April 2, 2025” and the title “Battery as well as battery module and battery pack”. Technical field

[0002] The present invention relates to the technical field of batteries, in particular a battery. State of the art

[0003] A stacked battery is a lithium-ion battery in which the positive electrode sheet, separator, and negative electrode sheet are stacked sequentially, creating a multi-layered stacked cell. Compared to conventional wound batteries, stacked batteries offer better space utilization and more uniform current distribution, making them suitable for high-energy-density, high-power applications such as electric vehicles and energy storage systems.

[0004] The separator plays a crucial role in stacked batteries. When assembling stacked batteries, the separator is typically placed between the positive and negative electrode sheets to prevent a short circuit caused by direct contact between them. Furthermore, the separator is usually wrapped around the outer surfaces of both the positive and negative electrode sheets to prevent direct contact between these sheets and the battery casing.

[0005] An insulating adhesive is typically applied to the ends of the separator, which is wound around the positive and negative electrode sheets, to ensure the separator remains tightly wound. However, in various application scenarios, the end of the separator (i.e., the point where the separator winding terminates) may be located on a different side for each cell. Since the area at the end of the separator coated with the insulating adhesive has a dense structure, while the area without the adhesive is relatively loose, this difference leads to unevenness in the separator on one side of the battery, which in turn affects the coating of the subsequent insulating layer. Content of the invention

[0006] The purpose of the present invention is to provide a battery in which the influence of the separator on the coating of the insulating film is reduced by matching the insulating film, the separator and the electrode sheet, in order to solve the problem that in conventional batteries, irregularities of the separator can impair the coating of the insulating film.

[0007] To achieve the above-mentioned purpose, the following technical solution is used in the present application: A battery, including: a housing body having a first end and a second end arranged opposite each other in a first direction, the housing body having a receiving chamber and the first end being provided with an opening connecting the receiving chamber to the outside environment; a cover plate connected to the opening to isolate the recording chamber from the outside environment; a cell comprising a separator and several electrode sheets, wherein the several electrode sheets are arranged stacked on top of each other to form a non-continuous stacked structure, wherein the separator is arranged between two adjacent electrode sheets and encloses them to the outside of the stacked structure, wherein the separator has an end piece, while the end piece is attached to the side of the cell facing the first end, wherein the number of cells is at least two, and the two cells are arranged in the receiving chamber, wherein the two adjacent cells are arranged in a direction perpendicular to the first direction, and the end pieces of the two cells are arranged on opposite sides of the stacked structure, and wherein the end piece of at least one of the cells is attached to the side of the cell facing the first end; an insulating film that encloses the outside of the cell and extends towards the first end, the insulating film being provided with a notch facing the cover plate to accommodate the side of the cell where the end piece is located; and in the first direction, wherein the electrode sheet located in the outermost layer and near the second end serves as a reference electrode sheet, the distance between the outer edge of the reference electrode sheet facing the second end and the outer edge of the cell facing the second end is L, the thickness of the insulating film is D1, the elastic modulus of the separator is E, and the above parameters satisfy the following condition: 250≤(D1×E) / L≤4000, where the distance L satisfies the condition: 3 ≤ L ≤ 200 µm, and / or the thickness D1 of the insulating film satisfies the condition: 50 ≤ D1 ≤ 150 µm, and / or the elastic modulus E of the separator satisfies the condition: 200 ≤ E ≤ 2000 MPa.

[0008] A battery according to the invention offers the following advantages compared to the prior art: By adjusting the distance L between the outer edge of the reference electrode sheet (facing the second end) and the outer edge of the cell (facing the second end), as well as the thickness D1 of the insulating film and the elastic modulus E of the separator, the insulating film, separator, and electrode sheet of this battery or battery group can be matched. This ensures a proper fit between the insulating film and the cover plate, and the distance between the insulating film and the cover plate remains within a suitable range to guarantee the insulation performance between the cell and the housing. Furthermore, when welding the cover plate to the housing, this distance prevents the insulating film from being penetrated and melted during the welding process, which would occur if the distance between the insulating film and the cover plate were too small. The battery module or battery group...The battery pack of the present application uses the aforementioned battery and has the advantages of the aforementioned battery. Illustration of the attached figures Fig. Figure 1 shows a schematic representation of a battery in embodiment 1 of the present invention; Fig. Figure 2 shows a schematic representation of the housing body in embodiment 1 of the present invention; Fig. Figure 3 shows a top view of the battery in embodiment 1 of the present invention; Fig. Figure 4 shows a schematic section along line AA in Fig. 3; Fig. 5 is an augmentation of B in Fig. 4; Fig. 6 is an increase in C in Fig. 4; Fig.Figure 7 shows a schematic representation of the stacking structure in embodiment 1 of the present invention, in which the stacking direction is perpendicular to the first direction; Fig. Figure 8 shows a schematic representation of the stacking structure in embodiment 1 of the present invention, in which the stacking direction runs parallel to the first direction; Fig. Figure 9 shows a schematic representation of the battery group in embodiment 2 of the present invention; Fig. Figure 10 shows a schematic representation of the housing body in embodiment 2 of the present invention; Fig. 11 shows a top view of the battery group in embodiment 2 of the present invention; Fig. Figure 12 shows a schematic section along line DD in Fig. 11; Fig. 13 is an augmentation of E in Fig. 12; Fig.14 is an augmentation of F in Fig. 12; Fig. Figure 15 shows a schematic representation of the battery group in embodiment 2 of the present invention, in which the fastening element is located on the rear side; Fig. Figure 16 shows a schematic representation of the battery group in embodiment 2 of the present invention, in which the fastening element is located at the front.

[0009] Included: 100 batteries; X first direction; Y second direction; Z third direction; 1 Housing body; 1a first end; 1b second end; 1c Recording chamber; 2 Cover plate; 3 openings; 4 cells; 4a Separator; 4b Electrode sheet; 4b1 positive electrode sheet; 4b2 negative electrode sheet; 5 Fastening element; 6 insulating film; 6a Notch; 7 Insulating element; 8 separating element. Specific embodiment

[0010] The detailed embodiment of the present invention is described below with reference to the accompanying drawings and exemplary embodiments. The following exemplary embodiments serve to illustrate the present invention but do not limit its scope.

[0011] In describing the present invention, it should be noted that when a component is described as "attached to another component" or "arranged on another component," this can mean that it is arranged directly on that other component or indirectly via that other component. When a component is described as "connected to another component," it can be connected to that other component either directly or indirectly. The terms "mount," "connect," and "connect" are to be understood in a broad sense; for example, the connection may be fixed, detachable, or integrated; it may be mechanical or electrical; it may be a direct connection or an indirect connection via an intermediate medium; it may be a connection within two components or an interaction between two components.For a person skilled in the art, the specific meaning of the above-mentioned terms in connection with the invention is understandable in each individual case.

[0012] In describing the present invention, it should be noted that the terms “height”, “top”, “bottom”, “vertical”, “horizontal”, “top”, “bottom”, “inside” and “outside” used in the present invention refer to the directions or positions shown in the accompanying drawings and serve only to clarify and simplify the description of the present invention, but do not mean or imply that the devices or elements in question must have a particular orientation, be constructed in a particular orientation or be operated in a particular orientation; they are therefore not to be understood as limiting the present invention.

[0013] In describing the present invention, it should be noted that the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating a relative importance or as an implicit indication of the number of the designated technical features. Therefore, a feature designated as "first" or "second" may explicitly or implicitly comprise one or more of these features. Example 1

[0014] With reference to Fig. 1, Fig. 2, Fig. 3, Fig. 4, Fig. 5, Fig. 6, Fig. 7 to Fig.Figure 8 of this embodiment provides a battery 100 comprising a housing body 1 and a cover plate 2, wherein the housing body 1 has a first end 1a and a second end 1b which are arranged opposite each other in the longitudinal direction, wherein the housing body 1 is provided with an opening 3 at the first end 1a and a receiving chamber 1c is provided inside the housing body 1, the receiving chamber 1c being connected to the external environment via the opening 3. The cover plate 2 is connected to the opening 3 in order to insulate the receiving chamber 1c from the external environment.

[0015] In this embodiment, the housing body 1 has a first direction X, a second direction Y, and a third direction Z, each perpendicular to the others. The direction in which the first end 1a and the second end 1b are located is considered the first direction X of the housing body 1, i.e., the longitudinal direction; the direction in which the long side of the opening 3 is located is considered the second direction Y of the housing body 1, i.e., the left and right direction; and the direction in which the short side of the opening 3 is located is considered the third direction Z of the housing body 1, i.e., the forward and backward direction.

[0016] In the receiving chamber 1c, a cell 4 is arranged, wherein the cell 4 comprises a separator 4a and several electrode sheets 4b, the several electrode sheets 4b being arranged stacked on top of each other to form a stacking structure, and the separator 4a being arranged between two adjacent electrode sheets 4b and enclosing them to the outside of the stacking structure.

[0017] It is understandable that the electrode sheet 4b of battery 100 typically comprises two electrode sheets of opposite polarity, namely the positive electrode sheet 4b1 and the negative electrode sheet 4b2; the electrode arrangement of battery 100 functions through the movement of metal ions between the positive electrode sheet 4b1 and the negative electrode sheet 4b2. The cell's cycle process consists of metal ions migrating from the positive electrode sheet 4b1 to the negative electrode sheet 4b2 and subsequently from the negative electrode sheet 4b2 back to the positive electrode sheet 4b1. As in Fig.As shown in Figure 4, in cell 4 of this embodiment the positive electrode sheet 4b1 and the negative electrode sheet 4b2 are arranged alternately stacked on top of each other, i.e. the positive electrode sheet 4b1 and the negative electrode sheet 4b2 are stacked on top of each other in the sequence a negative electrode sheet 4b2 - a positive electrode sheet 4b1 - a negative electrode sheet 4b2 - a positive electrode sheet 4b1 - a negative electrode sheet 4b2, creating a stacked structure, with a negative electrode sheet 4b2 being located in the outermost layer of the stacked structure.

[0018] It should be noted that in this embodiment 1, cell 4 is a stacked cell. For example, if cell 4 is a stacked cell, several electrode sheets 4b are stacked on top of each other to form a non-continuous stacked structure, i.e., any two adjacent positive electrode sheets 4b1 form a non-continuous structure and / or any two adjacent negative electrode sheets 4b2 form a non-continuous structure.

[0019] It is understood that the housing body 1 serves to enclose components such as the cell and an electrolyte. The housing body 1 can have various shapes and dimensions, for example, the shape of a cuboid or a hexagonal prism; the shape of the housing body 1 can be determined according to the specific shape and dimensions of the cell. The housing body 1 can be made of various materials, including, but not limited to, copper, iron, aluminum, stainless steel, aluminum alloys, plastic, etc.

[0020] In each cell 4, the separator 4a is positioned between two adjacent electrode sheets 4b and extends to the outer surface of the stacked structure, thus enclosing the outermost electrode sheet 4b. In the case of a stacked cell, the positive electrode sheet 4b1, the separator 4a, and the negative electrode sheet 4b2 are stacked sequentially on top of each other during the assembly of the cell 4.The upper and lower sides of the electrode sheet 4b are distinguished based on the stacking direction of the electrode sheet 4b. The separator 4a is positioned between the positive electrode sheet 4b1 and the negative electrode sheet 4b2 and covers both the upper and lower sides of the positive electrode sheet 4b1 as well as the upper and lower sides of the negative electrode sheet 4b2, thus separating the adjacent positive and negative electrode sheets 4b1 and 4b2 from each other to prevent direct contact between them. Furthermore, the separator 4a is typically a continuous film extending from the interior of the stack structure to its exterior, thus enveloping the outer surface of the stack structure and separating the electrode sheets 4b from the housing body 1.

[0021] It should be noted that the separator 4a of the battery 100 is typically made of a porous insulating material whose main function is to separate the positive electrode sheet 4b1 and the negative electrode sheet 4b2 while allowing the passage of lithium ions. The separator 4a usually has an end piece (i.e., a point where the winding of the separator 4a ends) to which a fastening element 5 is attached for tensioning the separator 4a. For example, in some batteries 100, the end piece of the separator 4a is connected to an insulating tape as the fastening element 5, with one end of the insulating tape attached to the end piece of the separator 4a and the other end attached to another point on the separator 4a. By tensioning the insulating tape, the separator 4a can be tightened, thus tightly encasing the stack structure.

[0022] Depending on the type of casing of the separator 4a, the dimensions of the separator 4a, the dimensions of the cell 4, etc., the end piece of the separator 4a can be located on different sides of the cell 4 in different cells 4. For example, in battery 100 according to this embodiment 1, the end piece of the separator 4a is attached to the side of the cell 4 that faces the first end 1a.

[0023] An insulating film 6 is typically arranged between cell 4 and housing 1 to separate the battery 100 from the housing 1 and thus ensure the safety, reliability, and performance stability of the battery 100. (Referring to) Fig.This is explained in section 4 using the example of a stacked cell: the insulating film 6 encloses the side of the cell 4 facing the second end 1b, and the insulating film 6 extends to the first end 1a to enclose the outer circumference of the cell 4 and thus separate the cell 4 from the housing body 1. Furthermore, the insulating film 6 has a notch 6a facing the cover plate 2 to accommodate the side of the cell 4 where the end piece is located, so that the insulating film 6 runs outside the side with the end piece and does not enter the side with the end piece, thus preventing any impairment of the connection between the cell 4 and the electrode column of the cover plate 2.

[0024] It is understandable that both the separator 4a and the insulating film 6 are arranged in the receiving chamber 1c and that the fit between the two affects the mounting of the cell 4 in the housing body 1, which in turn affects the performance of the battery 100.

[0025] In some batteries 100, mutual agreement between the separator 4a and the insulating film 6 can be achieved by adjusting the fit between them. For example, in the first direction X, the electrode sheet 4b, located in the outermost layer and near the second end 1b, is used as a reference electrode sheet, where the distance between the outer edge of the reference electrode sheet facing the second end 1b and the outer edge of the cell 4 facing the second end 1b is L, the thickness of the insulating film 6 is D1, the elastic modulus of the separator 4a is E, and the parameters mentioned above satisfy the following condition: 250≤(D1×E) / L≤5000.

[0026] For example, the ratio of the three quantities - the distance L between the outer edge of the reference electrode sheet directed towards the second end 1b and the outer edge of the cell 4 directed towards the second end 1b, the thickness D1 of the insulating film 6 and the modulus of elasticity E of the separator 4a - can take on one of the following values ​​according to equation (1): 250, 350, 450, 550, 650, 750, 850, 950, 1000, 1500, 2000, 2500, 3000, 3500, 4000, 4500 or 5000.

[0027] It is understandable that the three quantities – the distance L between the outer edge of the reference electrode sheet facing the second end 1b and the outer edge of the cell 4 facing the second end 1b, the thickness D1 of the insulating film 6, and the modulus of elasticity E of the separator 4a – reflect the fit between the insulating film 6 and the separator 4a. If the value of the three quantities – the distance L between the outer edge of the reference electrode sheet facing the second end 1b and the outer edge of the cell 4 facing the second end 1b, the thickness D1 of the insulating film 6, and the modulus of elasticity E of the separator 4a – is too small according to equation (1), this can easily lead to the insulating film 6 being welded through and melting during the welding process between the housing body 1 and the cover plate 2.If the value of the three quantities - the distance L between the outer edge of the reference electrode sheet directed towards the second end 1b and the outer edge of the cell 4 directed towards the second end 1b, the thickness D1 of the insulating film 6 and the modulus of elasticity E of the separator 4a - is too large according to equation (1), this can easily lead to an excessively large gap between the insulating film 6 and the cover plate 2, which impairs the insulating performance of the battery 100.If the three parameters – the distance L between the outer edge of the reference electrode sheet facing the second end 1b and the outer edge of the cell 4 facing the second end 1b, the thickness D1 of the insulating film 6, and the modulus of elasticity E of the separator 4a – satisfy the equation (1) above, the insulating film 6, the separator 4a, and the electrode sheet 4b can be matched, ensuring that the insulating film 6 and the cover plate 2 form a proper fit and that the distance between the insulating film 6 and the cover plate 2 is within a suitable range to guarantee the insulating performance between the cell 4 and the housing body 1. Furthermore, when the cover plate 2 is welded to the housing body 1, the distance between the insulating film 6 and the cover plate 2 prevents the insulating film 6 from being penetrated and melted during the welding process, which would occur if the distance between the insulating film 6 and the cover plate 2 were too small.

[0028] It should be noted that the outermost electrode sheet 4b refers to the electrode sheet 4b that is located furthest out in the stacking structure in the direction of the electrode sheets 4b. As in Fig. As shown in Figure 4, the electrode sheet 4b, which is located at the outermost point in the third direction Z of the stacked structure of cell 4 and is close to the second end 1b, is the foremost negative electrode sheet 4b2 as well as the rearmost negative electrode sheet 4b2. As shown in Fig. As shown in Figure 8, in a stacked structure of cell 4 along the first direction X, the electrode sheet 4b, which is located in the outermost layer and close to the second end 1b, is the lowest negative electrode sheet 4b2.

[0029] It should be noted that the distance L between the side of the reference electrode sheet facing the second end 1b and the corresponding side of the cell 4 facing the second end 1b corresponds to the thickness of the separator 4a, which is located on the side of the reference electrode sheet facing the second end 1b. Naturally, the separator 4a can be either single-layer or multi-layer in various battery 100 configurations; therefore, the thickness of the separator 4a generally corresponds to the product of the thickness of a single separator and the number of separators.

[0030] To verify whether, if the structural parameters of the battery 100 provided in this embodiment 1 satisfy the above equation (1), i.e., if the distance L between the outer edge of the reference electrode sheet facing the second end 1b and the outer edge of the cell 4 facing the second end 1b, the thickness D1 of the insulating film 6 and the modulus of elasticity E of the separator 4a are matched, the insulating film 6 of the battery 100 according to this embodiment 1 ensures good insulating performance compared to other batteries 100 and does not melt easily by welding, 9 test groups were carried out in this embodiment 1; see Table 1: In Table 1, test cases 1 to 9 were tested using the structure of battery 100 according to this embodiment 1; that is, for batteries 100 in test cases 1 to 15, the distance L, the thickness D1 of the insulating film 6, and the modulus of elasticity E of the separator 4a satisfy the relationship given in equation (1) above. Comparison examples 1 to 4 show different battery designs; that is, for comparison examples 1 to 4, the distance L, the thickness D1 of the insulating film, and the modulus of elasticity E of the separator do not satisfy the relationship given in equation (1) above.

[0031] The test method for separator penetration is as follows: Insulating films of varying thicknesses and separators with different moduli of elasticity were selected according to Table 1 and assembled into a cell. The cell was then inserted into the housing, and the cover plate was welded to the housing using laser welding technology. During the welding process, the welding power was maintained at 2000 W, and the welding speed was set to 50 mm / s. After completion of the welding, the battery was disassembled to verify that the insulating film had been penetrated.

[0032] The insulation performance test method is as follows: insulating films of varying thicknesses and separators with different moduli of elasticity were selected according to Table 1 and assembled into a cell. The cell was then inserted into the housing, the cover plate was sealed to the housing using laser welding, and the electrolyte solution was added. After a formation period, the battery was complete. Lithium iron phosphate was used as the material for the positive electrode. The battery was first charged to 3.25 V at a current of 1 / 3 C; after a waiting period of 10 minutes, it was then discharged to 2.5 V at a current of 1 / 3 C. After a resting period of 1 hour, the open-circuit voltage was measured and recorded and labeled V1.The charging and discharging process described above was then repeated; after a 10-minute rest period, 500 cycles were performed. After completion of the cycle, the battery was left to rest for 50 minutes, after which the open-circuit voltage was measured and recorded again and labeled V2. Finally, the voltage difference after the battery cycle was calculated using the formula ΔV = V1 - V2. Table 1 Thickness of insulating film (µm) Distance L(µm) Separator modulus of elasticity (MPa) Formula(D ×E) / L Is the insulating film completely welded through? Voltage difference (△V) Test case 1 60 10 305 1830,0 No 0,03 Test case 2 120 100 1497 1796,4 No 0,04 Test case 3 60 25 310 744,0 No 0,04 Test case 4 120 80 1494 2241,0 No 0,05 Test case 5 100 75 803 1070,7 No 0,06 Test case 6 50 3 202 3366,7 No 0,07 Test case 7 150 200 1995 1496,3 No 0,06 Test case 8 50 40 201 251,3 No 0,08 Test case 9 150 60 1999 4997,5 No 0,07 Comparative example 1 45 4 531 5973,8 No 0,21 Comparative example 2 60 210 822 234,9 Yes 0,04 Comparative example 3 50 45 213 236,7 Yes 0,05 Comparative example 4 150 55 1989 5424,5 No 0,25

[0033] Table 1 shows that if the three quantities - the distance L between the outer edge of the reference electrode sheet directed towards the second end 1b and the outer edge of the cell 4 directed towards the second end 1b, the thickness D1 of the insulating film 6 and the modulus of elasticity E of the separator 4a - satisfy the above equation (1), the insulating film 6 not only ensures excellent insulating performance between the cell 4 and the housing body 1, but also prevents the insulating film 6 from melting during the welding process between the cover plate 2 and the housing body 1.If the three quantities - the distance L between the outer edge of the reference electrode sheet directed towards the second end 1b and the outer edge of the cell 4 directed towards the second end 1b, the thickness D1 of the insulating film 6 and the modulus of elasticity E of the separator 4a - do not satisfy the relationship given in the above equation (1), the insulating film 6 may melt or the insulating performance between the cell 4 and the casing body 1 may be insufficient in the battery.

[0034] In this embodiment 1, the distance L between the outer edge of the reference electrode sheet directed towards the second end 1b and the outer edge of the cell 4 directed towards the second end 1b can, by way of example, satisfy the following condition: 3 ≤ L ≤ 200 µm; for example, the distance L can be one of the following dimensions: 3 µm, 4 µm, 5 µm, 6 µm, 7 µm, 8 µm, 9 µm, 10 µm, 20 µm, 30 µm, 40 µm, 50 µm, 60 µm, 70 µm, 80 µm, 90 µm, 100 µm, 110 µm, 120 µm, 130 µm, 140 µm, 150 µm, 160 µm, 170 µm, 180 µm, 190 µm, 200 µm.

[0035] In this embodiment 1, the thickness D1 of the insulating film can, by way of example, satisfy the following condition: 50 ≤ D1 ≤ 150 µm; for example, the thickness D1 of the insulating film can be one of the following dimensions: 50 µm, 60 µm, 70 µm, 80 µm, 90 µm, 100 µm, 110 µm, 120 µm, 130 µm, 140 µm or 150 µm.

[0036] In this embodiment 1, the elastic modulus E of the separator 4a can, for example, satisfy the following condition: 200 ≤ E ≤ 2000 MPa, for example, the elastic modulus E of the separator 4a can be one of the following values: 200 MPa, 300 MPa, 400 MPa, 500 MPa, 600 MPa, 700 MPa, 800 MPa, 900 MPa, 1000 MPa, 1100 MPa, 1200 MPa, 1300 MPa, 1400 MPa, 1500 MPa, 1600 MPa, 1700 MPa, 1800 MPa, 1900 MPa or 2000 MPa.

[0037] It is understandable that large amounts of heat are generated when welding the cover plate 2. If the insulating film 6 is too close to the cover plate 2, the heat generated during welding can easily be transferred to the insulating film 6, causing it to contract under the heat. This can easily lead to the cell protruding from the insulating film 6, creating a risk of contact between the cell and the housing body 1. Therefore, there is usually a certain distance between the insulating film 6 and the cover plate 2; that is, there is a certain distance in the first direction X between the side of the insulating film 6 facing the cover plate 2 and the side of the cover plate 2 facing the cell 4. In this embodiment 1, this distance is defined as the shortest perpendicular distance h1 between the insulating film 6 and the cover plate 2 in the first direction X.For example, in some batteries 100, the shortest vertical distance h1 between the insulating film 6 and the cover plate 2 in the first direction X can satisfy the following condition: 0.5 ≤ h1 ≤ 5 mm; for example, h1 can be one of the following dimensions: 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm or 5 mm.

[0038] If the distance between the insulating film 6 and the cover plate 2 satisfies h1, then the distance between the insulating film 6 and the cover plate 2 is, of course, well matched to the cell 4. Therefore, in this case, the electrode sheet 4b, which is located in the outermost layer and close to the second end 1b, is used as the reference electrode sheet 4b, where the three quantities – the distance L between the outer edge of the reference electrode sheet facing the second end 1b and 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 – also satisfy the following condition: 250≤(D1×E) / L≤4000.

[0039] For example, the ratio of the three quantities - the distance L between the outer edge of the reference electrode sheet directed towards the second end 1b and the outer edge of the cell 4 directed towards the second end 1b, the thickness D1 of the insulating film 6 and the modulus of elasticity E of the separator 4a - can take on one of the following values ​​according to equation (2): 250, 350, 450, 550, 650, 750, 850, 950, 1000, 1500, 2000, 2500, 3000, 3500 or 4000.

[0040] It should be noted that the cell 4 arranged in the receiving chamber 1c can be arranged in various ways; for example, the stacking direction of several electrode sheets 4b can run parallel to the first direction X. If, as in Fig. 1, Fig. 2, Fig. 3, Fig. 4, Fig. 5 to Fig. 6 and Fig.As shown in Figure 8, the stacking direction of several electrode sheets 4b is parallel to the first direction X. This parallel stacking of the multiple electrode sheets 4b makes it easier to keep the insulating film 6 and the separator 4a flat during the stacking process. This allows the cell 4 to be inserted more conveniently into the receiving chamber 1c and reduces wrinkling of the separator near the second end 1b. Therefore, in this case, the electrode sheet 4b located in the outermost layer and close to the second end 1b is used as the reference electrode sheet 4b. The three quantities – the distance L between the outer edge of the reference electrode sheet facing the second end 1b and 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 – also satisfy the following condition: 250≤(D1×E) / L≤3000.

[0041] For example, the ratio of the three quantities - the distance L between the outer edge of the reference electrode sheet directed towards the second end 1b and the outer edge of the cell 4 directed towards the second end 1b, the thickness D1 of the insulating film 6 and the modulus of elasticity E of the separator 4a - can take on one of the following values ​​according to equation (3): 250, 350, 450, 550, 650, 750, 850, 950, 1000, 1500, 2000, 2500 or 3000.

[0042] Of course, the stacking direction of several electrode sheets 4b can also be perpendicular to the first direction X. If, as in Fig. 1, Fig. 2, Fig. 3, Fig. 4, Fig. 5 to Fig. 6 and Fig.As shown in Figure 7, if the stacking direction of several electrode sheets 4b is perpendicular to the first direction X, the vertical stacking of the several electrode sheets 4b can result in the insulating film 6 and the separator 4a being subjected to a more uniform load during the stacking process, thereby reducing local stress concentrations in the insulating film 6 and the separator 4a. Furthermore, the housing body 1 can be reduced in size in the second direction Y or the third direction Z, thereby reducing the weld length between the housing body 1 and the cover plate 2, which in turn improves the weld yield between the housing body 1 and the cover plate 2.Therefore, in this case, the electrode sheet 4b, which is located in the outermost layer and is close to the second end 1b, is used as the reference electrode sheet 4b, where the three quantities - the distance L between the outer edge of the reference electrode sheet directed towards the second end 1b and the outer edge of the cell 4 directed towards the second end 1b, the thickness D1 of the insulating film 6 and the modulus of elasticity E of the separator 4a - also satisfy the following condition:. 1200≤(D1×E) / L≤5000.

[0043] For example, the ratio of the three quantities - the distance L between the outer edge of the reference electrode sheet directed towards the second end 1b and the outer edge of the cell 4 directed towards the second end 1b, the thickness D1 of the insulating film 6 and the modulus of elasticity E of the separator 4a - can take on one of the following values ​​according to equation (4): 1200, 1300, 1400, 1500, 2000, 2500, 3000, 3500, 4000, 4500 or 5000.

[0044] As in Fig. 1, Fig. 2, Fig. 3, Fig. 4, Fig. 5, Fig. 6, Fig. 7 to Fig. As shown in Figure 8, in some batteries 100 an insulating element 7 is arranged between the cell 4 and the cover plate 2. This insulating element serves to isolate the electrical connection component in the housing 1 from the cover plate 2, thus reducing the risk of a short circuit. The insulating element 7 is typically made of plastic, rubber, etc. Its insulating performance changes accordingly with the thickness of the insulating element 7. As an example of this embodiment 1, the thickness of the insulating element 7 is D2, where the thickness D2 of the insulating element 7 satisfies the following condition: 0.5 ≤ D2 ≤ 5 mm. For example, D2 can be one of the following dimensions: 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, or 5 mm.

[0045] The thickness D2 of the insulating element 7 satisfies the condition 0.5 ≤ D2 ≤ 5 mm. This ensures the insulating performance of the insulating element 7, thus improving the insulation between the cell 4 and the cover plate 2 and increasing the distance between the insulating film 6 and the cover plate 2. In this case, the electrode sheet 4b, located in the outermost layer and close to the second end 1b, is used as the reference electrode sheet 4b, where the three quantities – the distance L between the outer edge of the reference electrode sheet facing the second end 1b and the outer edge of the cell 4 facing the second end 1b, the thickness D1 of the insulating film 6, and the modulus of elasticity E of the separator 4a – also satisfy the following condition: 250≤(D1×E) / L≤2500.

[0046] For example, the ratio of the three quantities - the distance L between the outer edge of the reference electrode sheet directed towards the second end 1b and the outer edge of the cell 4 directed towards the second end 1b, the thickness D1 of the insulating film 6 and the modulus of elasticity E of the separator 4a - can take on one of the following values ​​according to equation (5): 250, 350, 450, 550, 650, 750, 850, 950, 1000, 1500, 2000, or 2500.

[0047] As in Fig. 1, Fig. 2, Fig. 3, Fig. 4, Fig. 5, Fig. 6, Fig. 7 to Fig. As shown in Figure 8, in some batteries 100 a separating element 8 is arranged between the cell 4 and the casing 1, which serves to separate the casing 1 from the cell 4 in order to reduce the risk of a short circuit. The separating element 8 is arranged between the side of the cell 4 facing the second end 1b and the casing 1; it can be made of materials such as plastic or rubber.

[0048] It is understandable that changing the thickness of the separating element 8 will correspondingly affect its insulating performance. As an example for this embodiment 1, the thickness of the separating element 8 is D3, where the thickness D3 of the separating element 8 satisfies the following condition: 0.5 ≤ D3 ≤ 3 mm. For example, D3 can be one of the following dimensions: 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, or 3 mm.

[0049] The thickness D3 of the separating element 8 satisfies the condition 0.5 ≤ D3 ≤ 3 mm. This ensures the insulating performance of the separating element 8 and guarantees that the separating element 8 supports the cell 4 and reduces the effects of the R-angle of the housing body 1 on the cell 4. In this case, the electrode sheet 4b, located in the outermost layer and close to the second end 1b, is used as the reference electrode sheet 4b, where the three quantities – the distance L between the outer edge of the reference electrode sheet facing the second end 1b and the outer edge of the cell 4 facing the second end 1b, the thickness D1 of the insulating film 6, and the modulus of elasticity E of the separator 4a – also satisfy the following condition: 1800≤(D1×E) / L≤2500.

[0050] For example, the ratio of the three quantities - the distance L between the outer edge of the reference electrode sheet directed towards the second end 1b and the outer edge of the cell 4 directed towards the second end 1b, the thickness D1 of the insulating film 6 and the modulus of elasticity E of the separator 4a - can take on one of the following values ​​according to equation (6): 1800, 1900, 2000, 2100, 2200, 2300, 2400 or 2500.

[0051] Based on the above-mentioned battery 100, this embodiment 1 also provides a battery module comprising at least two of the aforementioned batteries 100, wherein the two batteries are electrically connected to each other by a series connection or a parallel connection.

[0052] Based on the above-mentioned battery module, this embodiment 1 also provides a battery pack comprising a housing and at least two of the aforementioned battery modules, wherein the two battery modules are arranged in the housing and electrically connected to each other. Example 2

[0053] With reference to Fig. 9, Fig. 10, Fig. 11, Fig. 12, Fig. 13, Fig. 14, Fig. 15 to Fig.In this embodiment 2, a battery 100 is provided, comprising a housing body 1 and a cover plate 2. The housing body 1 has a first end 1a and a second end 1b, which are arranged opposite each other in the longitudinal direction. The housing body 1 is provided with an opening 3 at the first end 1a, and a receiving chamber 1c is provided inside the housing body 1. The cover plate 2 is connected to the opening 3 to isolate the receiving chamber 1c from the external environment.

[0054] In this embodiment 2, the housing body 1 has a first direction X, a second direction Y, and a third direction Z, each of which is perpendicular to the others. The direction in which the first end 1a and the second end 1b are located is considered the first direction X of the housing body 1, i.e., the longitudinal direction; the direction in which the long side of the opening 3 is located is considered the second direction Y of the housing body 1, i.e., the left and right direction; and the direction in which the short side of the opening 3 is located is considered the third direction Z of the housing body 1, i.e., the forward and backward direction.

[0055] A cell assembly is arranged in the receiving chamber 1c. In this embodiment 2, the cell assembly comprises two cells 4, each cell 4 comprising a separator 4a and several electrode sheets 4b, the several electrode sheets 4b being arranged stacked on top of each other to form a stacking structure, and two adjacent cells being arranged in the stacking direction of the stacking structure.

[0056] It is understandable that the battery's electrode sheet 4b typically comprises two electrode sheets of opposite polarity, namely the positive electrode sheet 4b1 and the negative electrode sheet 4b2; the battery's electrode arrangement functions through the movement of metal ions between the positive electrode sheet 4b1 and the negative electrode sheet 4b2. The cell's cycling process consists of metal ions migrating from the positive electrode sheet 4b1 to the negative electrode sheet 4b2 and subsequently from the negative electrode sheet 4b2 back to the positive electrode sheet 4b1. As in Fig. 9, Fig. 10, Fig. 11, Fig. 12, Fig. 13, Fig. 14, Fig. 15 to Fig.As shown in Figure 16, in cell 4 of this embodiment 2 the positive electrode sheet 4b1 and the negative electrode sheet 4b2 are arranged alternately stacked on top of each other, i.e. the positive electrode sheet 4b1 and the negative electrode sheet 4b2 are stacked on top of each other in the sequence a negative electrode sheet 4b2 - a positive electrode sheet 4b1 - a negative electrode sheet 4b2 - a positive electrode sheet 4b1 - a negative electrode sheet 4b2, creating a stacked structure, with a negative electrode sheet 4b2 being located in the outermost layer of the stacked structure.

[0057] It should be noted that in this embodiment 2, cell 4 is a stacked cell, and the housing 1 serves to enclose components such as the cell and an electrolyte. The housing 1 can have various shapes and dimensions, for example, the shape of a cuboid or a hexagonal prism; the shape of the housing 1 can be determined according to the specific shape and dimensions of the cell. The housing 1 can be made of various materials, including, but not limited to, copper, iron, aluminum, stainless steel, aluminum alloys, plastic, etc.

[0058] In each cell 4, the separator 4a is arranged between two adjacent electrode sheets 4b and wound on the outside of the stacked structure in the stacking direction of the electrode sheets 4b to enclose 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 stacked sequentially on top of each other.The upper and lower sides of the electrode sheet 4b are distinguished based on the stacking direction of the electrode sheet 4b. The separator 4a is positioned between the positive electrode sheet 4b1 and the negative electrode sheet 4b2 and covers both the upper and lower sides of the positive electrode sheet 4b1 as well as the upper and lower sides of the negative electrode sheet 4b2, thus separating the adjacent positive and negative electrode sheets 4b1 and 4b2 from each other to prevent direct contact between them. Furthermore, the separator 4a is typically a continuous film extending from the interior of the stack structure to its exterior, thus enveloping the outer surface of the stack structure and separating the electrode sheets 4b from the housing body 1.

[0059] It should be noted that the battery separator 4a is typically made of a porous insulating material whose main function is to separate the positive electrode sheet 4b1 and the negative electrode sheet 4b2 while allowing the passage of lithium ions. The end of the separator 4a (i.e., the point where the winding of the separator 4a ends) usually needs to be connected to a fastening element 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 fastening element 5, with one end of the tape attached to the end of the separator 4a and the other end attached to another point on the separator 4a. By tensioning the insulating tape, the separator 4a can be tightened, thus tightly encasing the stack structure.

[0060] An insulating film 6, for example an insulating film, is typically arranged between the battery 100 and the housing body 1 to separate the battery 100 from the housing body 1 and thus ensure the safety, reliability and performance stability of the battery. As shown in Fig. 9, Fig. 10, Fig. 11, Fig. 12, Fig. 13, Fig. 14, Fig. 15 to Fig. As shown in Figure 16, the insulating film 6 encloses the two cells on the side facing the second end 1b, and the insulating film 6 extends to the first end 1a to enclose the outer circumference of the two cells and thus separate the cells from the housing body 1. Furthermore, the insulating film 6 is located on the outside of the end face of the two cells facing the first end 1a and does not extend into the end face of the two cells facing the first end 1a, so as not to impair the connection of the battery 100 with the electrode column of the cover plate 2.

[0061] It is understandable that the separator 4a of each cell of battery 100 has its own end piece. In conjunction with the fastening element 5, the voltage at the end piece of separator 4a is generally higher than at other points on the separator 4a. Thus, if the end pieces of separators 4a of two cells are located on opposite sides of the stack structure, differences in the flatness of the separator 4a on one side of the same battery 100 will occur. In this context, with reference to Fig. 9, Fig. 10, Fig. 11, Fig. 12, Fig. 13, Fig. 14, Fig. 15 to Fig.16, to note that in the case where the end pieces of the separators 4a of the two cells are arranged on different sides of the stack structure and the end piece of the separator 4a of one cell is attached to the side of the cell 4 facing the first end 1a, in the battery 100 of this embodiment 2, in the first direction X, the electrode sheet 4b, which is located in the outermost layer and is close to the outer circumference of the housing body 1, is used as the reference electrode sheet, wherein the distance between the outer edge of the reference electrode sheet facing the second end 1b and the outer edge of the cell 4 facing the second end 1b is L, the thickness of the insulating film 6 is D1, the modulus of elasticity of the separator 4a is E, and the above-mentioned parameters satisfy the following condition: 250≤(D1×E) / L≤4000.

[0062] For example, the ratio of the three quantities - the distance L between the outer edge of the reference electrode sheet directed towards the second end 1b and the outer edge of the cell 4 directed towards the second end 1b, the thickness D1 of the insulating film 6 and the modulus of elasticity E of the separator 4a - can take on one of the following values ​​according to equation (7): 250, 350, 450, 550, 650, 750, 850, 950, 1000, 1500, 2000, 2500, 3000, 3500, 4000, 4500 or 5000.

[0063] It is understandable that the three quantities – the distance L between the outer edge of the reference electrode sheet facing the second end 1b and the outer edge of the cell 4 facing the second end 1b, the thickness D1 of the insulating film 6, and the modulus of elasticity E of the separator 4a – reflect the fit between the insulating film 6 and the separator 4a. If the value of the three quantities – the distance L between the outer edge of the reference electrode sheet facing the second end 1b and the outer edge of the cell 4 facing the second end 1b, the thickness D1 of the insulating film 6, and the modulus of elasticity E of the separator 4a – is too small according to equation (7), this can easily lead to the insulating film 6 being welded through and melting during the welding process between the housing body 1 and the cover plate 2.If the value of the three quantities - the distance L between the outer edge of the reference electrode sheet directed towards the second end 1b and the outer edge of the cell 4 directed towards the second end 1b, the thickness D1 of the insulating film 6 and the modulus of elasticity E of the separator 4a - is too large according to equation (7), this can easily lead to an excessively large gap between the insulating film 6 and the cover plate 2, which impairs the insulating performance of the battery.If the three parameters – the distance L between the outer edge of the reference electrode sheet facing the second end 1b and the outer edge of the cell 4 facing the second end 1b, the thickness D1 of the insulating film 6, and the modulus of elasticity E of the separator 4a – satisfy the aforementioned equation (7), the insulating film 6, the separator 4a, and the electrode sheet 4b can be matched, ensuring that the insulating film 6 and the cover plate 2 form a proper fit and that the distance between the insulating film 6 and the cover plate 2 is within a suitable range to guarantee the insulating performance between the cell 4 and the housing body 1. Furthermore, when the cover plate 2 is welded to the housing body 1, the distance between the insulating film 6 and the cover plate 2 prevents the insulating film 6 from being penetrated and melted during the welding process, which would occur if the distance between the insulating film 6 and the cover plate 2 were too small.

[0064] It should be noted that in this battery 100, the two cells 4 are arranged in the stacking direction of the stack structure. Therefore, the electrode sheet 4b, which in battery 100 of this embodiment 2 is located in the outermost layer and is close to the outer circumference of the housing body 1, is the foremost negative electrode sheet 4b2 in the front cell 4 and the rearmost negative electrode sheet 4b2 in the rear cell 4.

[0065] It should be noted that the distance L between the outer edge of the reference electrode sheet facing the second end 1b and the outer edge of the cell 4 facing the second end 1b corresponds to the thickness of the separator 4a, which is located on the side of the reference electrode sheet 4b facing the second end 1b. Naturally, the separator 4a can be single-layered or multi-layered in various battery configurations; therefore, the thickness of the separator 4a is generally the product of the thickness of a single separator and the number of separators.

[0066] It should be noted that if the end piece of separator 4a of one cell is attached to the side of cell 4 facing the first end 1a, there are several possible arrangements for the end piece of separator 4a of the other cell of this battery 100. For example, the end piece of separator 4a of one cell 4 is arranged on the side of the cell facing the second end 1b, or, in the arrangement direction of the two cells 4, the end piece of separator 4a of one cell 4 is arranged on any side of the arrangement direction of the cells 4, i.e., the end piece of separator 4a of one cell 4 is arranged on the opposite side face of two adjacent cells, or the end piece of separator 4a of one cell 4 is arranged on the side face of the cell facing the outer circumference of the housing body 1. The two arrangements are explained in detail below in this embodiment 2.

[0067] As in Fig. 9, Fig. 10, Fig. 11, Fig. 12, Fig. 13, Fig. 14, Fig. 15 to Fig. 16 is shown in the Fig.In the cell arrangement shown in Figure 12, the front cell 4 is designated as a first cell and the rear cell 4 as a second cell. If the end piece of the separator 4a of one cell is located on the side of the cell facing the second end 1b, i.e., if the end piece of the separator 4a of the first cell is located on the bottom of the stacked structure and the end piece of the separator 4a of the second cell is located on the top of the stacked structure, then in this case the fastening element 5 of the second cell is also located on the top, with the separator 4a being relatively tight on the top of the second cell, while it is relatively loose on the bottom, back, and front of the second cell, and the insulating film 6 covers the bottom and back of the second cell.In this context, in the first direction X, the electrode sheet 4b, which is located in the outermost layer and close to the outer circumference of the housing body 1, is used as the reference electrode sheet, where the distance between the outer edge of the reference electrode sheet directed towards the second end 1b and the outer edge of the cell 4 directed towards the second end 1b is L, the thickness of the insulating film 6 is D1, the elastic modulus of the separator 4a is E, and the parameters mentioned above satisfy the following condition: 250≤(D1×E) / L≤3000.

[0068] For example, the ratio of the three quantities - the distance L between the outer edge of the reference electrode sheet directed towards the second end 1b and the outer edge of the cell 4 directed towards the second end 1b, the thickness D1 of the insulating film 6 and the modulus of elasticity E of the separator 4a - can take on one of the following values ​​according to equation (8): 250, 350, 450, 550, 650, 750, 850, 950, 1000, 1500, 2000, 2500 or 3000.

[0069] As in Fig. 9, Fig. 10, Fig. 11, Fig. 12, Fig. 13, Fig. 14, Fig. 15 to Fig.As shown in Figure 16, in a case where the end piece of the separator 4a of a cell 4 is located on any side of the arrangement direction of the cell 4, there is a case where the end piece of the separator 4a of a cell is located on the side of the cell facing the outer circumference of the housing body 1, i.e., the end piece of the separator 4a of the first cell is located on the bottom of the stack structure, while the end of the separator 4a of the second cell is located on the back of the stack structure. There is also a case where the end of the separator 4a of a cell is located on the opposite side of two adjacent cells, i.e., the end of the separator 4a of the first cell is located on the bottom of the stack structure, while the end of the separator 4a of the second cell is located on the front of the stack structure.

[0070] In both cases, the fastening element 5 of the second cell is located either on the back or on the front; accordingly, the separator 4a fits more tightly on the back or front of the second cell, while it fits more loosely on the other sides of the second cell, and the insulating film 6 covers the underside and the back of the second cell. Therefore, when the second cell and the insulating film 6 are fitted together, the holding force of the separator 4a is lower on only one side of the second cell, which makes it easier for the insulating film 6 to adhere to the second cell.In this context, in the first direction X, the electrode sheet 4b, which is located in the outermost layer and close to the outer circumference of the housing body 1, is used as the reference electrode sheet, where the distance between the outer edge of the reference electrode sheet directed towards the second end 1b and the outer edge of the cell 4 directed towards the second end 1b is L, the thickness of the insulating film 6 is D1, the elastic modulus of the separator 4a is E, and the parameters mentioned above satisfy the following condition: 250≤(D1×E) / L≤3000.

[0071] For example, the ratio of the three quantities - the distance L between the outer edge of the reference electrode sheet directed towards the second end 1b and the outer edge of the cell 4 directed towards the second end 1b, the thickness D1 of the insulating film 6 and the modulus of elasticity E of the separator 4a - can take on one of the following values ​​according to equation (9): 250, 350, 450, 550, 650, 750, 850, 950, 1000, 1500, 2000, 2500 or 3000.

[0072] It should be noted that in the battery 100 according to this embodiment 2, two adjacent cells are arranged along the stacking direction of the stack structure, i.e., the two adjacent cells are arranged in the forward and reverse directions, and that the separator 4a in this embodiment 2 is arranged between two adjacent electrode sheets 4b and is wound in the stacking direction of the electrode sheets 4b on the outside of the stack structure, i.e., the separator 4a in this embodiment 2 is wound in the forward and reverse directions on the outside of the stack structure. Therefore, even if the end piece of this separator 4a of this cell is arranged on the side of the cell facing the outer circumference of the housing body 1, it is oriented only towards the rear of the housing body 1 and not towards the left or right side of the housing body 1.Of course, the following applies to other battery designs: If two adjacent cells are arranged in the left and right direction, the end piece of the separator 4a of this cell is accordingly oriented towards the left or right side of the housing body 1 and not towards the front or back of the housing body 1.

[0073] It is understandable that the thickness of the separator 4a affects its stiffness. A thicker separator 4a has a higher stiffness; when the separator 4a is bent, a greater restoring force is generated, making it difficult to fit it tightly against the electrode sheet 4b. Furthermore, a thicker separator 4a tends to wrinkle during winding, resulting in a loose winding structure. Naturally, the thickness of the separator 4a also increases its insulating capacity, thus preventing contact between the cell 4 and the housing 1.Taking into account the insulating fit between the housing body 1 and the cell 4, the thickness of the separator 4a wound in the stack structure must be adjusted; for example, in the arrangement direction of the two cells 4, at least one cell 4 must satisfy the following condition: the distance between the outer edge of the electrode sheet 4b on the side near the housing body 1 and the outer edge of the corresponding cell 4 is S1, the distance between the outer edge of the electrode sheet 4b that is near the adjacent side of two cells 4 and the outer edge of the corresponding cell 4 is S2, where S1 > S2. That is to say,The thickness of the separator 4a on the front of the first cell is greater than the thickness of the separator 4a on the back of the first cell, and the thickness of the separator 4a on the back of the second cell is greater than the thickness of the separator 4a on the front of the second cell, in order to ensure good insulation between the housing body 1 and the cell 4.

[0074] Naturally, in this context, the distance S1 between the outer edge of the electrode sheet 4b on the side near the housing body 1 and the outer edge of the corresponding cell 4, as well as the distance S2 between the outer edge of the electrode sheet 4b located near the adjacent side of two cells 4 and the outer edge of the corresponding cell 4, influence the fit between the separator 4a and the electrode sheet 4b. Therefore, the fit between the insulating film 6 and the separator 4a must be adjusted accordingly.For example, in the first direction X, the electrode sheet 4b, which is located in the outermost layer and close to the outer circumference of the housing body 1, is used as the reference electrode sheet, where the distance between the outer edge of the reference electrode sheet directed towards the second end 1b and the outer edge of the cell 4 directed towards the second end 1b is L, the thickness of the insulating film 6 is D1, the elastic modulus of the separator 4a is E, and the parameters mentioned above satisfy the following condition: 800≤(D1×E) / L≤3500.

[0075] For example, the ratio of the three quantities - the distance L between the outer edge of the reference electrode sheet directed towards the second end 1b and the outer edge of the cell 4 directed towards the second end 1b, the thickness D1 of the insulating film 6 and the modulus of elasticity E of the separator 4a - can take on one of the following values ​​according to equation (10): 800, 850, 900, 950, 1000, 1500, 2000, 2500, 3000 or 3500.

[0076] In summary, it can be said that in the battery 100 of this embodiment, by adjusting the distance L between the outer edge of the reference electrode sheet 4b facing the second end 1b and the outer edge of the cell 4 facing the second end 1b, the thickness D1 of the insulating film 6 and the modulus of elasticity E of the separator 4a, an optimal match between the insulating film 6, the separator 4a and the electrode sheet 4b can be achieved, whereby the insulating film 6 and the cover plate 2 form a suitable fit and the distance between the insulating film 6 and the cover plate 2 is in a suitable range to ensure the insulating performance between the cell 4 and the housing body 1.Furthermore, the distance between the insulating film 6 and the cover plate 2 prevents the insulating film 6 from being welded through and melted during the welding process when the cover plate 2 is welded to the housing body 1. This would occur if the distance between the insulating film 6 and the cover plate 2 were too small. The battery module or battery pack of the present application uses the aforementioned battery 100 and exhibits the advantages of the aforementioned battery 100.

[0077] The foregoing descriptions represent only preferred embodiments of the present invention. It should be noted that a person skilled in the art in this field can, without deviating from the basic technical principle of the present invention, make various improvements and substitutions which are also to be regarded as belonging to the scope of protection of the present invention.

[0078] The present invention discloses a battery relating to the technical field of batteries, comprising a housing body, a cover plate, a cell, and an insulating film. By adjusting the distance L between the outer edge of the reference electrode sheet facing the second end and the outer edge of the cell facing the second end, as well as the thickness D1 of the insulating film and the elastic modulus E of the separator, the insulating film, the separator, and the electrode sheet are matched to each other, ensuring that the insulating film and the cover plate form a suitable fit and that the distance between the insulating film and the cover plate is within a suitable range to guarantee the insulating performance between the cell and the housing body.Furthermore, the distance between the insulating film and the cover plate prevents the insulating film from being welded through and melted during the welding process when the cover plate is welded to the housing body, which would be the case if the distance between the insulating film and the cover plate were too small.

Claims

Battery, characterized in that it comprises: a housing body having a first end and a second end arranged opposite each other in a first direction, the housing body having a receiving chamber and the first end being provided with an opening connecting the receiving chamber to the outside environment; a cover plate connected to the opening to insulate the receiving chamber from the outside environment;a cell comprising a separator and several electrode sheets, wherein the several electrode sheets are arranged stacked on top of each other to form a non-continuous stacked structure, wherein the separator is arranged between two adjacent electrode sheets and encloses them to the outside of the stacked structure, wherein the separator has an end piece, while the end piece is attached to the side of the cell facing the first end, wherein the number of cells is at least two, and the two cells are arranged in the receiving chamber, wherein the two adjacent cells are arranged in a direction perpendicular to the first direction, and the end pieces of the two cells are arranged on opposite sides of the stacked structure, and wherein the end piece of at least one of the cells is attached to the side of the cell facing the first end;an insulating film encasing the outside of the cell and extending towards the first end, the insulating film having a notch facing the cover plate to accommodate the side of the cell where the end piece is located; and in the first direction, the electrode sheet located in the outermost layer and near the second end serving as a reference electrode sheet, the distance between the outer edge of the reference electrode sheet facing the second end and the outer edge of the cell facing the second end being L, the thickness of the insulating film being D1, the elastic modulus of the separator being E, and the above parameters satisfying the following condition: 250 ≤ ( D1 × E) / L ≤ 4000; where the distance L satisfies the condition: 3 ≤ L ≤ 200 µm, and / or the thickness D 1 The insulating film's condition: 50 ≤ D 1 ≤ 150 µm is met, and / or the elastic modulus E of the separator meets the condition: 200 ≤ E ≤ 2000 MPa. 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, where 0.5 ≤ h1 ≤ 5 mm applies, and that the distance L, the thickness D1 of the insulating film and the modulus of elasticity E of the separator satisfy the following condition: 250 ≤ ( D1 × E)L ≤ 4000. Battery according to claim 1, characterized in that the stacking direction of the multiple electrode sheets is perpendicular to the first direction and that the distance L, the thickness D1 of the insulating film and the modulus of elasticity E of the separator satisfy the following condition: 250 ≤ ( D 1 × E ) L ≤ 3000. Battery according to claim 1, characterized in that the stacking direction of the multiple electrode sheets is parallel to the first direction and that the distance L, the thickness D1 of the insulating film and the modulus of elasticity E of the separator satisfy the following condition: 1200 ≤ ( D 1 × E ) L ≤ 4000. Battery according to claim 1, characterized in that an insulating element is arranged between the cell and the cover plate, wherein the thickness of the insulating element is D2 and the thickness D2 of the insulating element satisfies the condition: 0.5 ≤ D2 ≤ 5 mm, and wherein the distance L, the thickness D1 of the insulating film and the modulus of elasticity E of the separator satisfy the following condition: 250 ≤ ( D1 × E)L ≤ 2500. Battery according to claim 1, characterized in that the battery further comprises: a separating element arranged between the side of the cell facing the second end and the housing body, wherein the thickness of the separating element is D3 and the thickness D3 of the separating element satisfies the condition: 0.5 ≤ D3 ≤ 3 mm and wherein the distance L, the thickness D1 of the insulating film and the modulus of elasticity E of the separator satisfy the following condition: 1800 ≤ ( D1 × E)L ≤ 2500. Battery according to claim 1, characterized in that the end piece of the cell is arranged on the side of the cell facing the second end, and that the distance L, the thickness D1 of the insulating film and the modulus of elasticity E of the separator satisfy the following condition: 250 ≤ ( D 1 × E ) L ≤ 3000. Battery according to claim 1, characterized in that, in the arrangement direction of the two cells, the end piece of one of the cells is arranged on any side of the arrangement direction of the cell and that the distance L, the thickness D1 of the insulating film and the modulus of elasticity E of the separator satisfy the following condition: 250 ≤ ( D 1 × E ) L ≤ 3500. Battery according to claim 1, characterized in that, in the arrangement direction of the two cells, at least one of the cells fulfills the following requirement, wherein: the distance between the outer edge of the electrode sheet on the side facing the housing body and the outer edge of the corresponding cell is S1, while the distance between the outer edge of the electrode sheet on the side facing the two adjacent cells and the outer edge of the corresponding cell is S2, wherein S1 > S2; and the distance L, the thickness D1 of the insulating film and the modulus of elasticity E of the separator fulfill the following condition: 800 ≤ (D1 × E) / L ≤ 3500.

Images