Battery

Abstract

The utility model discloses a battery which comprises a shell, a battery cell and an insulating film, the battery cell comprises a positive pole lug and a negative pole lug, and the positive pole lug and the negative pole lug are positioned at two opposite ends of the battery cell; the insulating film comprises a bottom, a first side wall and a second side wall, and thickening areas are arranged on the side edges, close to the positive pole lug and the negative pole lug, of the first side wall and the second side wall. Compared with the prior art, the thickening area is arranged on the insulating film, so that the gap between the thinning area of the pole piece of the battery cell and the shell can be effectively reduced, and the pre-tightening force of the thinning area of the pole piece is enhanced, so that the large surface of the battery cell is stressed more uniformly, and the lithium precipitation risk of the battery is reduced.

Description

Technical Field

[0001] This utility model relates to the field of fuel cell structural design, and in particular to a battery for reducing the risk of lithium plating. Background Technology

[0002] During the cell assembly process, a significant gap exists between the thinned area of ​​the electrode and the aluminum casing, which can easily lead to lithium plating at the upper edge of the electrode. Lithium plating refers to the phenomenon where, during battery charging and discharging, lithium ions cannot be completely embedded in the carbon material on the negative electrode and instead precipitate out as metallic lithium. This phenomenon can severely impact battery performance and safety, potentially causing capacity decay, increased internal resistance, and even thermal runaway.

[0003] Specifically, during assembly, if the gap between the thinned area of ​​the electrode and the aluminum shell is too large, the electrode is prone to mechanical deformation during charge-discharge cycles, leading to poor contact. This poor contact affects the uniformity and consistency of the battery, increases the battery's internal resistance, and causes an increase in local current density, thereby exacerbating lithium plating. Furthermore, mechanical stress concentration at the upper edge of the electrode also promotes lithium metal deposition, further aggravating the lithium plating problem. Utility Model Content

[0004] In view of this, the present invention proposes a battery for reducing the risk of lithium plating. By setting a thickened area, the gap between the thinned area of ​​the cell electrode and the outer casing can be effectively reduced, and the pre-tightening force of the electrode thinning area can be enhanced, making the force on the large surface of the cell more uniform and reducing the risk of lithium plating. The technical solution of the present invention is as follows:

[0005] This utility model proposes a battery, including a casing, a cell, and an insulating film;

[0006] The battery cell includes a positive electrode tab and a negative electrode tab, and the positive electrode tab and the negative electrode tab are located at opposite ends of the battery cell;

[0007] The insulating film includes a bottom, a first sidewall, and a second sidewall, wherein the first sidewall and the second sidewall have thickened areas on the sides near the positive electrode tab and the negative electrode tab.

[0008] In some embodiments, both the first sidewall and the second sidewall are provided with an intermediate area and a thickened area, with the intermediate area sandwiched between the two thickened areas.

[0009] In some embodiments, the difference D between the thickness of the thickened region and the thickness of the intermediate region is in the range of 0 < D ≤ 1 mm.

[0010] In some preferred embodiments, the difference D between the thickness of the thickened region and the thickness of the intermediate region is in the range of 0.05≤D≤0.3mm.

[0011] In some implementations, the thickness is the same at all locations within the thickened area.

[0012] In some embodiments, the thickness of the thickened region gradually increases in the direction away from the intermediate region.

[0013] In some implementations, the width of the thickened area is 0.1mm-10mm.

[0014] In some embodiments, the insulating film is further provided with a welding area for welding to the underlying plastic.

[0015] In some embodiments, a thinning zone is provided in the area where the thickened area overlaps with the welding area.

[0016] In some embodiments, the thickness of the thinning region is less than the thickness of the thickening region.

[0017] In some embodiments, the thickness of the thinned region is greater than or equal to the thickness of the intermediate region.

[0018] In some implementations, the width of the thickened region is the same as that of the thinned region.

[0019] In some embodiments, a transition region is provided between the thickened region and the thinned region, and the thickness of the transition region gradually decreases from the thickened region to the thinned region.

[0020] In some implementations, the thicknessed region, the transition region, and the thinning region have the same width.

[0021] In some embodiments, the housing includes a shell and a top cover assembly, the top cover assembly including an L-shaped connecting piece, one end of which is connected to a tab and the other end of which is welded to a pole assembly.

[0022] This device has the following advantages:

[0023] 1. An insulating film is wrapped around the outside of the battery cell, providing excellent insulation performance and ensuring the safety and stability of the battery.

[0024] 2. The sidewall edge of the insulating film is provided with a thickened area. This design effectively reduces the gap between the thinned area of ​​the cell electrode and the outer shell, and enhances the tightness of the assembly.

[0025] 3. The thickened area increases the pre-tightening force in the electrode thinning area, making the force on the large surface of the cell more uniform and reducing local stress concentration.

[0026] Through the above structural optimization and enhanced preload design, the risk of lithium plating in the battery can be significantly reduced, and the safety and lifespan of the battery can be improved. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only one embodiment of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Identical parts are indicated by the same reference numerals. It should be noted that the terms "front," "rear," "left," "right," "up," and "down" used in the following description refer to directions in the accompanying drawings, while the terms "bottom surface," "top surface," "inner," and "outer" refer to directions toward or away from the geometric center of a specific part, respectively.

[0029] Figure 1 This is a front view of the insulating film in an embodiment of the present invention;

[0030] Figure 2 This is a schematic diagram of the insulating film in an embodiment of the present invention;

[0031] Figure 3 This is a schematic diagram of the battery in an embodiment of the present invention;

[0032] The meanings of the reference numerals in the above figures are as follows:

[0033] 1. Top cover plate;

[0034] 2. Adapter plate;

[0035] 3. Battery cells;

[0036] 4. Insulating film;

[0037] 41. Bottom;

[0038] 42. First sidewall;

[0039] 43. Second sidewall;

[0040] 441. The first part of the third sidewall

[0041] 442. The second part of the third sidewall

[0042] 45. Fourth side wall

[0043] 451. The first part of the fourth side wall

[0044] 452. The second part of the fourth sidewall

[0045] 46. ​​Middle area;

[0046] 47. Thickened area;

[0047] 48. Welding area;

[0048] 49. Thinning zone;

[0049] shell. Detailed Implementation

[0050] The technical solution of this utility model will be clearly and completely described below with reference to the embodiments and accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0051] Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used in the detailed description is for the purpose of describing particular embodiments only and is not intended to limit the invention; the terms “comprising” and “having” and any variations thereof in the specification, claims and foregoing description of the invention are intended to cover non-exclusive inclusion.

[0052] In the description of the specific embodiments of this utility model, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this utility model, "multiple" means two or more, unless otherwise explicitly defined.

[0053] In this invention, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this invention. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this invention can be combined with other embodiments.

[0054] In the description of this utility model embodiment, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this utility model, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0055] Throughout this invention, numerical values ​​represent approximate measurements or limits of a range to cover minute deviations from a given value, as well as embodiments having approximately the mentioned value and embodiments having the exact mentioned value. Except for the working examples provided at the end of the detailed description, all numerical values ​​of parameters, quantities, or conditions in the appended claims should be understood to be modified in all cases by the term “about,” regardless of whether “about” actually appears before the numerical value. “About” indicates that the stated numerical value allows for some minute inaccuracy that is somewhat close to the exact value of the value; approximately or reasonably close to the value; almost. If the inaccuracy provided by “about” is not otherwise understood in this common sense in the art, then “about” as used in this invention at least indicates a variation that can be produced by common methods of measuring and using such parameters. For example, “about” may include a variation of less than or equal to 5%, optionally less than or equal to 4%, optionally less than or equal to 3%, optionally less than or equal to 2%, optionally less than or equal to 1%, optionally less than or equal to 0.5%, and in some respects, optionally less than or equal to 0.1%.

[0056] Additionally, the disclosure of the range includes the disclosure of all values ​​across the entire range and the disclosure of further subdivided ranges, including the endpoints and subranges given for these ranges.

[0057] The embodiments of the present invention will be described in more detail below through examples. It should be noted that the embodiments of the present invention are not limited to these examples.

[0058] During the cell assembly process, a significant gap exists between the thinned area of ​​the electrode and the aluminum casing, which can easily lead to lithium plating at the upper edge of the electrode. Lithium plating refers to the phenomenon where, during battery charging and discharging, lithium ions cannot be completely embedded in the carbon material on the negative electrode and instead precipitate out as metallic lithium. This phenomenon can severely impact battery performance and safety, potentially causing capacity decay, increased internal resistance, and even thermal runaway.

[0059] Specifically, during assembly, if the gap between the thinned area of ​​the electrode and the aluminum shell is too large, the electrode is prone to mechanical deformation during charge-discharge cycles, leading to poor contact. This poor contact affects the uniformity and consistency of the battery, increases the battery's internal resistance, and causes an increase in local current density, thereby exacerbating lithium plating. Furthermore, mechanical stress concentration at the upper edge of the electrode also promotes lithium metal deposition, further aggravating the lithium plating problem.

[0060] In view of this, the present invention proposes a battery for reducing the risk of lithium plating. By setting a thickened area, the gap between the thinned area of ​​the cell electrode and the outer casing can be effectively reduced, and the pre-tightening force of the electrode thinning area can be enhanced, making the force on the large surface of the cell more uniform and reducing the risk of lithium plating. The technical solution of the present invention is as follows: Example

[0061] In a specific embodiment 1, such as Figures 1-3 As shown, a battery includes a casing 5, a battery cell 3, and an insulating film 4. The battery cell 3 includes a positive electrode tab and a negative electrode tab, which are located at opposite ends of the battery cell 3. The insulating film 4 is located between the casing 5 and the battery cell 3, and wraps around the outside of the battery cell 3. The insulating film 4 includes a bottom 41, a first sidewall 42, and a second sidewall 43. The first sidewall 42 and the second sidewall 43 correspond to two opposite large surfaces of the battery cell 3, and the first sidewall 42 and the second sidewall 43 are connected to the bottom 41. The first sidewall 42 and the second sidewall 43 have thickened areas 47 on the sides near the positive electrode tab and the negative electrode tab.

[0062] In the above settings, the thickened area 47 can effectively reduce the gap between the thinned area 49 of the cell 3 electrode and the outer shell 5, enhance the pre-tightening force of the electrode thinning area, make the large surface of the cell 3 more uniformly stressed, and reduce the risk of lithium plating in the battery.

[0063] In this embodiment, the first sidewall 42 extends to both sides with a third sidewall first portion 441 and a fourth sidewall first portion 451, wherein the first sidewall 42 and the third sidewall first portion 441 share one side, and the first sidewall 42 and the fourth sidewall first portion 451 share the other side.

[0064] The second sidewall 43 extends to the second part of the third sidewall 442 and the second part of the fourth sidewall 452 on both sides. The second sidewall 43 and the second part of the third sidewall 442 share one side, and the second sidewall 43 and the second part of the fourth sidewall 452 share the other side.

[0065] After the battery is assembled, the first part 441 and the second part 442 of the third sidewall are stacked to form the third sidewall, and the first part 451 of the fourth sidewall and the second part 452 of the fourth sidewall are stacked to form the fourth sidewall 45.

[0066] In some embodiments, both the first sidewall 42 and the second sidewall 43 are provided with an intermediate region 46 and a thickened region 47, with the intermediate region 46 disposed between the two thickened regions 47. The thickness of the thickened region 47 is greater than the thickness of the intermediate region 46.

[0067] In some embodiments, the difference D between the thickness of the thickened region 47 and the thickness of the intermediate region 46 is in the range of 0 < D ≤ 1 mm.

[0068] In some preferred embodiments, the difference D between the thickness of the thickened region 47 and the thickness of the intermediate region 46 is in the range of 0.05≤D≤0.3mm.

[0069] In some implementations, the thickness is the same at all locations within the thickened area 47.

[0070] In some implementations, the width of the thickened region 47 is 0.1 mm to 10 mm.

[0071] In some embodiments, the thickened area 47 includes a plurality of strip insulating films 4, each strip insulating film 4 being connected by an adhesive method.

[0072] In some embodiments, the insulating film 4 is further provided with a welding area 48, which is used to weld with the lower plastic to fix the battery cell and prevent the battery cell from shaking inside the housing.

[0073] Specifically, in this embodiment, the welding area 48 is located on the top of the insulating film 4. It can be understood that after the battery is assembled, the top of the insulating film 4 is connected to the top cover assembly.

[0074] In some embodiments, the welding area 48 and the thickened area 47 partially overlap.

[0075] In some embodiments, a thinning region 49 is provided in the area where the thickened region 47 overlaps with the welding region 48.

[0076] In this embodiment, a thinning region 49 is provided at the top of the thickened region 47. The thickness of the thinning region 49 is less than the thickness of the thickened region 47, but greater than or equal to the thickness of the intermediate region 46.

[0077] In some implementations, the thickness of the thickened region 47 is the same as the width of the thinned region 49.

[0078] In some embodiments, a transition region is provided between the thickened region 47 and the thinned region 49, and the thickness of the transition region gradually decreases from the thickened region 47 to the thinned region 49.

[0079] In some implementations, the thicknessed region 47, the transition region, and the thinning region 49 have the same width.

[0080] In some embodiments, the housing 5 includes a housing and a top cover assembly. The top cover assembly typically includes a top cover plate 1 and an adapter piece 2. The adapter piece 2 typically includes an L-shaped connecting piece, one end of which is connected to the electrode tab and the other end is welded to the electrode post assembly.

[0081] In the above configuration, the top cover 1 includes the terminal assembly, electrolyte filling assembly, and explosion-proof assembly to ensure the battery's safety performance under normal and abnormal operating conditions. The adapter 2 connects the internal tabs of the cell 3 to the leads of the top cover 1, serving as a current conductor. It typically uses highly conductive and reliable materials, such as nickel foil or aluminum alloy, to reduce resistance and energy loss. The cell 3 is the core of the battery, composed of a positive electrode, negative electrode, separator, and electrolyte, storing and releasing energy through an electrochemical reaction. The insulating film 4 inside the cell 3 isolates the positive and negative electrodes to prevent short circuits and provides insulation between components. It typically uses high-temperature resistant and highly insulating materials, such as polypropylene or polyimide. The outer casing 5 is generally made of aluminum alloy or stainless steel, providing mechanical support and protection. Together with the top cover 1, it forms a sealed container through laser welding or riveting to prevent electrolyte leakage and the influence of the external environment on the battery.

[0082] This device offers the following advantages: 1. The insulating film wraps around the outside of the battery cell, providing excellent insulation performance and ensuring battery safety and stability. 2. Thickened areas are provided on the sidewall edges of the insulating film. This design effectively reduces the gap between the thinned area of ​​the battery cell electrode and the outer casing, enhancing assembly tightness. 3. The thickened areas increase the pre-tightening force in the electrode thinning area, resulting in more uniform stress distribution across the large surface area of ​​the battery cell and reducing localized stress concentration. Through the above structural optimization and enhanced pre-tightening force design, the risk of lithium plating in the battery can be significantly reduced, improving battery safety and lifespan. Example

[0083] The difference between Example 2 and Example 1 is that the thickness of the thickened region 47 gradually increases in the direction away from the middle region 46;

[0084] The welding area 48 is located on top of the insulating film 4 and does not overlap with the thickened area 47. The remaining technical features are the same.

[0085] The advantage of this design is that the electrodes inside the battery cell are generally thinner at the edges and gradually thinner outwards from the center of the electrode. By matching the electrode thickness, sufficient preload can be ensured without increasing the thickness of the battery cell edges too much.

[0086] It should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A battery, characterized in that, Includes the casing, battery cell, and insulating film; The battery cell includes a positive electrode tab and a negative electrode tab, and the positive electrode tab and the negative electrode tab are located at opposite ends of the battery cell; The insulating film includes a bottom, a first sidewall, and a second sidewall, wherein the first sidewall and the second sidewall have thickened areas on the sides near the positive electrode tab and the negative electrode tab.

2. The battery according to claim 1, characterized in that, Both the first sidewall and the second sidewall are provided with a middle area and a thickened area, with the middle area sandwiched between the two thickened areas.

3. A battery according to claim 2, characterized in that, The difference D between the thickness of the thickened area and the thickness of the intermediate area is in the range of 0 < D ≤ 1 mm.

4. A battery according to claim 1 or 2, characterized in that, The thickness is the same at all locations within the thickened area.

5. A battery according to claim 2, characterized in that, The thickness of the thickened area gradually increases in the direction away from the middle area.

6. A battery according to claim 1 or 2, characterized in that, The width of the thickened area is 0.1mm-10mm.

7. A battery according to claim 6, characterized in that, The insulating film also has a welding area for welding with the lower plastic.

8. A battery according to claim 7, characterized in that, A thinning zone is provided in the area where the thickened area overlaps with the welding area.

9. A battery according to claim 8, characterized in that, A transition zone is provided between the thickened zone and the thinned zone, and the thickness of the transition zone gradually decreases from the thickened zone to the thinned zone.

10. A battery according to claim 1, characterized in that, The outer casing includes a housing and a top cover assembly. The top cover assembly includes an L-shaped connecting piece, one end of which is connected to the electrode tab, and the other end is welded to the electrode post assembly.

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