Electrochemical equipment and electrical appliances

Abstract

The present application discloses an electrochemical device and an electrical equipment having the electrochemical device. The electrochemical device includes a housing. The housing includes a main body and a seal extending outward from an edge of the main body. The main body is used to accommodate an electrode assembly. The seal includes a first outer edge, an outer arcuate edge, and a second outer edge. The outer arcuate edge connects the first outer edge and the second outer edge. The outer arcuate edge protrudes toward the main body. The minimum radius of curvature of the outer arcuate edge is defined as r min If mm, r min ≧0.3, which can reduce the stress concentration at the sealing part corresponding to the outer arc edge in the drop mode, and further reduce the risk of the sealing part being torn and damaged in the drop mode of the battery, causing a safety accident.

Description

[Technical field]

[0001] The present application relates to the technical field of energy storage, in particular electrochemical devices and electrical appliances. [Background technology]

[0002] The use of irregular-shaped batteries improves the adaptability of batteries to electrical equipment structures, enriches battery application scenarios, and makes people's daily lives more convenient. However, the inventors' research has found that irregular-shaped batteries with inner corners are prone to tearing the sealed areas of the outer packaging at the inner corners of the battery in a dropped state, which affects the safety of the battery. Summary of the Invention [Problem to be solved by the invention]

[0003] Therefore, there is a need to provide electrochemical devices and electrical appliances that reduce the risk of the sealed areas at the inner corners tearing and becoming damaged if the battery is dropped. [Means for solving the problem]

[0004] In a first aspect of the present application, there is provided an electrochemical device including a housing. The housing includes a body portion and a seal portion extending outward from an edge of the body portion. The body portion is used to house an electrode assembly. The seal portion includes a first outer edge, an outer arcuate edge, and a second outer edge. The outer arcuate edge connects the first outer edge and the second outer edge. The outer arcuate edge protrudes toward the body portion. The minimum radius of curvature of the outer arcuate edge is defined as r. min If mm, r min By making the minimum curvature radius of the outer arc-shaped edge 0.3 mm or more, it is possible to reduce the stress concentration at the sealing part corresponding to the outer arc-shaped edge in a drop mode, and further to reduce the risk of a safety accident caused by the sealing part being torn and damaged in a drop mode of the battery.

[0005] Optionally, r min ≦5. In this case, the cutout of the outer arc edge is small, which can increase the sealing strength at the inner corner and reduce the risk of the seal being torn and damaged at the inner corner in the drop mode of the battery.

[0006] Optionally, in some embodiments of the present application, the seal portion further includes an inner arcuate edge protruding toward the body portion, and the distance from the minimum radius of curvature of the outer arcuate edge to the inner arcuate edge is D min In mm, D min ×r min ≧0.1. In this case, the seal width of the minimum radius of curvature portion of the outer arcuate edge can be adapted to the stress experienced therein, reducing the risk of the minimum radius of curvature portion being completely torn off and improving the reliability of the seal of the electrochemical device.

[0007] Optionally, in some embodiments of the present application, D min ≧1, the seal width at the minimum radius of curvature of the outer arcuate edge of the inside corner can be increased, further increasing the seal strength there and reducing the risk of the seal at the inside corner failing.

[0008] Optionally, in some embodiments of the present application, the minimum radius of curvature of the inner arcuate edge is R min mm, R min ≧2. In this case, when the inner arcuate edge receives an impact from the electrode assembly inside the electrochemical device in a drop mode, the impact force received there can be dispersed, and the risk of the seal at the inner corner being lost can be reduced.

[0009] Optionally, in some embodiments of the present application, the sealing portion includes a first flip portion and a second flip portion, the first outer edge being disposed on the first flip portion and the second outer edge being disposed on the second flip portion, in which case, in a drop mode, the first flip portion and the second flip portion can reduce a shear force received by the sealing portion when subjected to an impact, reduce a risk of the first outer edge and the second outer edge being torn, and increase the reliability of the seal of the electrochemical device.

[0010] Optionally, in some embodiments of the present application, the first flip portion extends along a first direction and the second flip portion extends along a second direction, the first direction intersecting the second direction.

[0011] Optionally, in some embodiments of the present application, the first flip portion includes a first folded portion and a second folded portion, the second folded portion being located between the first folded portion and the main body portion. By providing the first folded portion and the second folded portion, the reliability of the seal of the first fold portion can be improved.

[0012] Optionally, in some embodiments of the present application, the second flip portion includes a third bent portion and a fourth bent portion, the fourth bent portion being located between the third bent portion and the main body portion. The third bent portion and the fourth bent portion can improve the reliability of the seal of the second flip portion.

[0013] Optionally, in some embodiments of the present application, the shape of the housing includes any one of an L-shape, a V-shape, a U-shape, and a W-shape.

[0014] Optionally, in some embodiments herein, the electrode assembly includes at least one of a wound structure or a laminated structure.

[0015] A second aspect of the present application also provides an electricity-consuming facility including the electrochemical device of the above embodiment.

[0016] (Effects of the Invention) In the electrochemical device of the present application, by setting the minimum radius of curvature of the outer arcuate edge to 0.5 mm or more, stress concentration in the seal portion at the inner corner can be reduced in the drop mode, and tearing or damage to the seal portion at the inner corner can be reduced when the battery is dropped, thereby reducing the risk of causing a safety accident. [Brief description of the drawings]

[0017] [Figure 1] 1 shows a structural schematic diagram of an electrochemical device in some embodiments of the present application. [Diagram 2] 1 shows a schematic diagram of the structure of a housing in some embodiments of the present application. [Diagram 3] 2 shows a structural schematic diagram of a seal portion at an inside corner indicated by III in FIG. 1 in some embodiments of the present application. [Figure 4] 13A to 13C are schematic diagrams illustrating the structure of a sealing portion in some other embodiments of the present application. [Diagram 5] 1 shows a structural schematic diagram of an electricity-using device according to some embodiments of the present application. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] The following specific examples further illustrate the present application in conjunction with the above-mentioned drawings.

[0019] Hereinafter, technical aspects of the embodiments of the present application will be described with reference to the drawings of the embodiments of the present application. However, it is clear that the described embodiments are only some of the embodiments of the present application and do not include all of the embodiments.

[0020] When a component is considered to be "attached" to another component, it may be directly attached to the other component or there may be intermediate components involved. When a component is considered to be "connected" to another component, it may be directly connected to the other component or there may be intermediate components involved.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art of the present application. The terms used in the present application are for the purpose of describing particular embodiments only and are not intended to be limiting of the present application. As used herein, the term "or" includes any and all combinations of one or more of the associated listed items.

[0022] The electrochemical device according to the embodiment of the present application includes a housing. The housing includes a body portion and a seal portion extending outward from an edge of the body portion. The body portion is used to accommodate an electrode assembly. The seal portion includes a first outer edge, an outer arcuate edge, and a second outer edge. The outer arcuate edge connects the first outer edge and the second outer edge. The outer arcuate edge protrudes toward the body portion. The minimum radius of curvature of the outer arcuate edge is defined as r. min If mm, r min By making the minimum curvature radius of the outer arc-shaped edge 0.3 mm or more, it is possible to reduce the stress concentration in the seal portion corresponding to the outer arc-shaped edge of the inner corner in the drop mode, and further to reduce the risk of the seal portion at the inner corner being torn and damaged in the drop mode of the battery.

[0023] Hereinafter, some embodiments of the present application will be described in detail with reference to the accompanying drawings. The following examples and features in the examples may be combined with each other if not inconsistent.

[0024] 1, an electrochemical device 100 according to an embodiment of the present application includes a housing 10, an electrode assembly (not shown), and a tab assembly 20. The electrode assembly is provided within the housing 10. The tab assembly 20 is connected to the electrode assembly and is extended from the housing 10.

[0025] In one embodiment, the electrode assembly includes a wound structure formed by winding a positive electrode sheet, a negative electrode sheet, and a separator film disposed between the positive electrode sheet and the negative electrode sheet. In some other embodiments, the electrode assembly may be a laminated structure. That is, a plurality of positive electrode sheets, a separator film, and a negative electrode sheet are sequentially laminated to form the electrode assembly. In yet another embodiment, the electrode assembly includes a wound structure and a laminated structure. Optionally, the housing 10 includes an aluminum-plastic film.

[0026] The housing 10 includes a main body portion 10a and a seal portion 10b extending outward from an edge of the main body portion 10a. The main body portion 10a is for housing an electrode assembly. The tab assembly 20 protrudes from the seal portion 10b. Optionally, the shape of the housing 10 includes any one of an L-shape, a V-shape, a U-shape, and a W-shape. Optionally, the tab assembly 20 includes a first tab 21 and a second tab 22, and the first tab 21 and the second tab 22 are of opposite polarity. One of the first tab 21 and the second tab 22 is a positive electrode tab, and the other is a negative electrode tab.

[0027] In some embodiments, the housing 10 includes a first layer, a metal layer, and a second layer arranged in a laminated manner. The metal layer is disposed between the first layer and the second layer, and the second layer is located on the outermost layer of the housing. The second layer is a nylon layer or a composite layer of polyester resin (PET) and nylon, and can perform the protective functions of preventing contamination, corrosion resistance, and external damage. The metal layer can include one of aluminum and steel, and plays the role of waterproofing and barrier, and forms the housing. The first layer is a heat seal layer and may include a polymer. The polymer includes at least one of polypropylene and polyethylene, and is used to seal the housing 10, form the seal portion 10b, and separate the metal layer from the electrode assembly, reducing the risk of the electrode assembly in the housing 10 shorting out and the electrolyte corroding the metal layer.

[0028] As shown in FIG. 2, in one embodiment, the housing 10 includes a first shell 11 and a second shell 12. The first shell 11 is connected to the second shell 12. The first shell 11 and the second shell 12 are engageable along a connection position, and the first shell 11 and the second shell 12 are overlapped to form a body portion 10a for covering an electrode assembly. The periphery of the first shell 11 extends outward to form a plurality of first extensions 11a. The periphery of the second shell 12 extends outward to form a plurality of second extensions 12a. After the first shell 11 and the second shell 12 are engaged along the connection position, the first extensions 11a and the second extensions 12a are overlapped and hermetically connected to form a seal portion 10b.

[0029] 1, 2 and 3, the sealing portion 10b includes a first outer edge 101, an outer arcuate edge 102 and a second outer edge 103. The outer arcuate edge 102 is located between the first outer edge 101 and the second outer edge 103, and connects the first outer edge 101 and the second outer edge 103 to form an inner corner. Optionally, the shape of the inner corner includes any one of an L-shape, a V-shape, a U-shape and a W-shape. The outer arcuate edge 102 protrudes toward the main body portion 10a. The minimum curvature radius of the outer arcuate edge 102 is defined as r min If mm, r min ≧0.3. By limiting the minimum radius of curvature of the outer arcuate edge 102 to 0.3 mm or more, it is possible to reduce the stress concentration of the seal portion 10b at the inner corner in the drop mode, and further reduce the risk that the seal portion 10b will be torn and broken at the inner corner when the battery is dropped. In one embodiment, r min ≧0.5. In some embodiments, r min is 0.3, 0.4, 0.5, 0.8, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or a range between any two of the preceding numbers.

[0030] In one embodiment, r min≦5. In this case, the cutout of the outer arcuate edge 102 is small, which can increase the sealing strength at the inner corner and reduce the risk of the seal portion 10b being torn and damaged at the inner corner when the battery is dropped.

[0031] In one embodiment, the seal portion 10b further includes an inner arcuate edge 104 protruding toward the body portion 10a. The minimum radius of curvature of the inner arcuate edge 104 is R min mm, R min ≧2. In this case, when the inner arcuate edge 104 receives an impact from the internal electrode assembly of the electrochemical device 100 in a drop mode, the impact force received therein can be dispersed, and the risk of the seal at the inner corner being lost can be reduced. In some embodiments, R min is 2, 3, 4, 5, 6, 7, 8, 9, 10, or a range between any two of the preceding numbers.

[0032] In one embodiment, the distance from the minimum radius of curvature of the outer arcuate edge 102 to the inner arcuate edge 104 is D min In mm, D min ×r min ≧0.1. D min is the width between the minimum radius of curvature of the outer arcuate edge 102 and the inner arcuate edge 104. By satisfying the above relationship, the seal width of the minimum radius of curvature of the outer arcuate edge 102 can be matched to the stress experienced by the minimum radius of curvature, reducing the risk of the minimum radius of curvature being completely torn and improving the reliability of the seal of the electrochemical device. In some embodiments, D min ×r min is 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.5, 2, 2.5, 3, 4, 5, 6, or a range between any two of the preceding numbers.

[0033] In one embodiment, D minBy setting the value to ≧1, the seal width at the minimum radius of curvature of the outer arcuate edge 102 at the inside corner can be increased, further increasing the seal strength there, and reducing the risk of the seal 10b at the inside corner failing.

[0034] See Figures 2 and 3. Optionally, when the first extension 11a and the second extension 12a are all sealed, the inner arcuate edge 104 is the innermost arcuate side of the first extension 11a and the second extension 12a.

[0035] 2 and 4. Optionally, when the first extension 11a and the second extension 12a are partially sealed, the first extension 11a and the second extension 12a include a sealed area 1011 (i.e., the sealed portion 10b) and a non-sealed area 1012. The non-sealed area 1012 belongs to a part of the main body 10a. The inner arcuate edge 104 is an arcuate side of the sealed area 1011 that connects with the non-sealed area 1012.

[0036] As shown in FIG. 1 and FIG. 2, in one embodiment, the sealing portion 10b includes a first flip portion 101a and a second flip portion 102a. The first outer edge 101 is provided on the first flip portion 101a. The second outer edge 103 is provided on the second flip portion 102a. The first flip portion 101a and the second flip portion 102a are formed by folding back the sealing portion 10b, and the first flip portion 101a and the second flip portion 102a are abutted against the main body portion 10a. In this case, in the drop mode, the first flip portion 101a and the second flip portion 102a can reduce the tensile force received by the sealing portion 10b when impact is received, reduce the risk of the first outer edge 101 and the second outer edge 103 being torn, and improve the reliability of the seal of the electrochemical device.

[0037] Optionally, the first extension 11a includes a first extension segment 111, and the second extension 12a includes a second extension segment 121. After the first shell 11 and the second shell 12 are engaged along the connection position, the first extension segment 111 and the second extension segment 121 are overlapped and sealed and then folded to form the first flip portion 101a. Optionally, the first extension 11a further includes a third extension segment 112, and the second extension 12a further includes a fourth extension segment 122. After the first shell 11 and the second shell 12 are engaged along the connection position, the third extension segment 112 and the fourth extension segment 122 are overlapped and sealed and then folded to form the second flip portion 102a.

[0038] In one embodiment, the first flip portion 101a extends along a first direction and the second flip portion 102a extends along a second direction, the first direction intersecting the second direction. Optionally, the first direction is perpendicular to the second direction.

[0039] Optionally, the first flip portion 101a includes a first folded portion and a second folded portion. The first folded portion and the second folded portion are formed by folding along the width direction of the first flip portion 101a. The second folded portion connects the main body portion 10a and the first folded portion. When the first flip portion 101a abuts against the main body portion 10a, the second folded portion is located between the first folded portion and the main body portion 10a. By providing the first folded portion and the second folded portion, the reliability of the seal of the first flip portion 101a can be improved.

[0040] Optionally, the second flip portion 102a includes a third bent portion and a fourth bent portion. The third bent portion and the fourth bent portion are formed by folding along the width direction of the second flip portion 102a. The fourth bent portion connects the main body portion 10a and the third bent portion. When the second flip portion 102a abuts against the main body portion 10a, the fourth bent portion is located between the third bent portion and the main body portion 10a. By providing the third bent portion and the fourth bent portion, the reliability of the seal of the second flip portion 102a can be improved.

[0041] The present invention will now be further described with reference to specific examples.

[0042] Different r min Value, D min ×r min Value and D min value, R min Drop tests and hot box tests were conducted on L-shaped lithium-ion batteries in which both the first outer edge and the second outer edge are single folded sides, with the edges being 5 mm.

[0043] For the drop test method, 10 lithium-ion batteries are allowed to freely drop from a height of 1.2 m, and the drop is repeated 20 times. After the drop, the number of lithium-ion batteries whose seal corresponding to the inner corner is torn (i.e., the number of tears in the drop test) and the number of lithium-ion batteries whose seal corresponding to the inner corner is completely torn (i.e., the number of seal failures during the drop test) are counted.

[0044] For the hot box test method, 10 lithium-ion batteries are placed in an oven at 150°C for 30 minutes, and the seals on the inside corners are observed to see if there is any leakage. The number of batteries with leakage, i.e., the number of seals that have failed during the hot box test, is counted.

[0045] The experimental data is shown in the table below. [Table 1]

[0046] From Table 1, r min ≧0.3mm L-shaped lithium-ion battery, r min Compared to L-shaped lithium-ion batteries with a thickness of 0.1 mm, the number of tears in the seal at the inner corners during drop tests was significantly reduced, especially for minIt can be seen that when the minimum curvature radius of the outer arc-shaped edge is 0.5mm or more, the number of tears in the seals at the inner corners during the drop test of the L-shaped lithium-ion battery is 0. This is because, by making the minimum curvature radius of the outer arc-shaped edge 0.3mm or more, the stress concentration in the seals corresponding to the outer arc-shaped edge in the drop mode can be reduced, and thus the risk of the seals being torn and damaged in the drop mode of the battery can be reduced, which causes a safety accident.

[0047] Furthermore, D min ×r min If ≧0.1, the number of the seals at the inner corners completely torn during the drop test of the L-shaped lithium ion battery is 0. In this case, the seal width of the minimum curvature radius region of the outer arc-shaped edge can match the stress received there, so that the risk of the minimum curvature radius region being completely torn can be reduced, and the reliability of the seal of the battery can be improved.

[0048] Also, D min ≧1mm, the seal failure rate of L-type lithium-ion batteries in the hot box test is significantly reduced. This is because min If ≧1 mm, the seal width at the minimum radius of curvature of the outer arcuate edge of the inside corner can be increased, further increasing the seal strength at that area and reducing the risk of the seal at the inside corner failing.

[0049] 5, the present application also provides an electricity-using device 200 using the electrochemical device 100 according to any of the above embodiments. In one embodiment, the electricity-using device 200 of the present application may be, but is not limited to, a mobile phone, a drone, an electric car, an electric motorcycle, an electric-assisted bicycle, an electric tool, a large-scale home storage battery, or the like.

[0050] Those of ordinary skill in the art should recognize that the above embodiments are intended to illustrate the present application, rather than to limit the present application, and that any appropriate modifications and variations to the above embodiments fall within the scope of the present disclosure, provided they fall within the substantial spirit of the present application. [Explanation of symbols]

[0051] 100 Electrochemical device 10. Housing 10a Main body 10b Seal part 101a 1st Flip Section 102a 2nd flip section 101 First outer edge 102 Outer arc edge 103 Second outer edge 104 Inner arc edge 11 First Shell 12 Second Shell 11a 1st extension 111 First extension segment 112 3rd extension segment 12a 2nd extension 121 Second extension segment 122 4th extension segment 1011 Sealing Area 1012 Non-sealed area 200 Electrical Equipment 20 Tab Assembly 21 First Tab 22 Second Tab

Claims

1. 1. An electrochemical device comprising a housing, The housing includes a body portion and a seal portion extending outwardly from an edge of the body portion; the body portion is adapted to house an electrode assembly; The seal portion includes a first outer edge, an outer arcuate edge, and a second outer edge, the outer arcuate edge connects the first outer edge and the second outer edge, the outer arcuate edge projects toward the body portion; The minimum radius of curvature of the outer arcuate edge is r ｍｉｎ If mm, r ｍｉｎ ≧0.

3.

2. the seal portion further includes an inner arcuate edge protruding toward the body portion; The distance from the minimum radius of curvature of the outer arcuate edge to the inner arcuate edge is D ｍｉｎ In the case of mm, D ｍｉｎ ×r ｍｉｎ 2. The electrochemical device according to claim 1, wherein the ratio satisfies ≧0.

1.

3. D ｍｉｎ 3. The electrochemical device according to claim 2, wherein:

4. The minimum radius of curvature of the inner arcuate edge is R ｍｉｎ mm, R ｍｉｎ 3. The electrochemical device according to claim 2, wherein:

5. The sealing portion includes a first flip portion and a second flip portion, The first outer edge is provided on the first flip portion, 2. The electrochemical device of claim 1, wherein the second outer edge is disposed on the second flip portion.

6. 6. The electrochemical device according to claim 5, wherein the first flip portion extends along a first direction, the second flip portion extends along a second direction, and the first direction and the second direction intersect.

7. At least one of the following conditions is met: Condition (a) is that the first flip portion includes a first folded portion and a second folded portion, and the second folded portion is located between the first folded portion and the main body portion; The electrochemical device according to claim 5, characterized in that condition (b) is that the second flip portion includes a third bent portion and a fourth bent portion, and the fourth bent portion is located between the third bent portion and the main body portion.

8. 2. The electrochemical device according to claim 1, wherein the housing has a shape selected from the group consisting of an L-shape, a V-shape, a U-shape, and a W-shape.

9. 10. The electrochemical device of claim 1, wherein the electrode assembly comprises at least one of a wound structure or a stacked structure.

10. An electrical equipment comprising the electrochemical device according to any one of claims 1 to 9.

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