Battery shell and battery

Abstract

The invention belongs to the technical field of batteries, and discloses a battery shell and a battery, the battery shell comprises a cover plate body and a shell body, the cover plate body comprises a sealing part, an insertion part and a guide part, the insertion part is arranged between the sealing part and the guide part, and one side, deviating from the insertion part, of the guide part is provided with an assembly chamfer; the shell body is of a hollow shell structure provided with at least one opening, the inserting part and the guiding part are arranged in the shell body, the sealing part seals the opening of the shell body and is used for forming a sealed containing cavity, the wall face, attached to the inserting part, of the shell body is provided with a boss protruding towards the containing cavity, the shortest linear distance between the boss and the assembling chamfer is e, 0 mm < e < = 0.2 mm. According to the battery shell, the boss protruding towards the containing cavity is arranged, so that a gap between the assembling chamfer and the shell body is reduced, molten beads are blocked, the situations that the molten beads fall into the battery to scald a pole group and short circuit occurs are improved, and the use safety is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of battery, in particular to a battery shell and a battery. BACKGROUND

[0002] For the battery, the battery shell and the pole group are indispensable structures of the battery, and the pole group and the battery shell together constitute a complete battery. The battery shell is a container wrapping the pole group, which not only provides physical protection to prevent the pole group from being affected by the external environment, but also helps the pole group dissipate heat and maintain the stability of the battery. Therefore, the performance of the battery shell has an important influence on the assembly, safety and performance of the battery.

[0003] The battery shell generally includes a shell body provided with an opening and a cover plate closing the shell body. The cover plate and the shell body have two structure forms when assembled. One is to put the cover plate completely into the shell body, and to weld the gap between the cover plate and the shell body to achieve connection. The other is to set a limiting step on the cover plate. After the cover plate and the shell body are assembled, part of the cover plate is located in the shell body, and the other part is located outside the shell body. At this time, the connection is achieved by welding the gap between the shell body and the cover plate step from the side. In the above two ways, a chamfer is set on the cover plate to facilitate the insertion of the cover plate into the shell body.

[0004] The cover plate and the shell body are welded to form a molten pool. Generally, the width of the molten pool is greater than the depth. For the second structure form, the molten pool is welded from the side, so that the direction of the width of the molten pool is consistent with the direction of the thickness of the cover plate. In addition, a chamfer is provided on the cover plate. At this time, part of the molten pool is located in the gap between the chamfer of the cover plate and the shell body, thereby generating a bead. Due to the large gap, the large bead will fall into the battery, scalding the pole group and even causing short circuit, which has a great safety hazard. SUMMARY

[0005] The purpose of the present application is to provide a battery shell and a battery, which improves the scalding of the pole group and the short circuit caused by the bead falling into the battery, and improves the safety in use.

[0006] To achieve this purpose, the present application adopts the following technical solutions:

[0007] On the one hand, a battery shell is provided, which comprises:

[0008] The cover plate body comprises a closing part, a plug-in part and a guide part. The plug-in part is arranged between the closing part and the guide part. The guide part is provided with an assembly chamfer on the side away from the plug-in part.

[0009] The shell body is a hollow shell structure with at least one opening, the plug-in part and the guide part are arranged in the shell body, and the closure part closes the opening of the shell body to form a closed containing cavity, a wall surface of the shell body that is attached to the plug-in part is provided with a boss that protrudes into the containing cavity, the shortest straight line distance between the boss and the assembly chamfer is e, and 0mm

[0010] Optionally, the shell body and the cover plate body are welded along the junction of the shell body and the closure part, and a welding pool is formed, the welding pool includes a first molten zone overlapping the shell body, a second molten zone overlapping the cover plate body, and a third molten zone in the containing cavity, the volume of the third molten zone is V1, and 0.005mm 3 ≤V1≤0.027mm 3 .

[0011] Optionally, the depth dimension of the welding pool along a first direction is L1, and 0.3mm≤L1≤1mm.

[0012] Optionally, the width dimension of the welding pool along a second direction is L2, and 0.8mm≤L2≤1.5mm.

[0013] Optionally, the shell body includes a first surface inside the containing cavity and a second surface outside the containing cavity, the second surface is recessed in a direction close to the first surface and forms the boss at the first surface, a groove is formed at the second surface, the depth dimension of the groove along a first direction is a, and the thickness dimension of the shell body along the first direction is c, and 0.3≤a / c≤0.8.

[0014] Optionally, the shell body further includes a third surface abutting against the closure part, the distance dimension between the third surface and the groove along a second direction is h, and h≥1mm.

[0015] Optionally, the guide part includes a guide bottom surface parallel to the third surface and a guide inclined surface at an angle to the third surface, the angle between the guide bottom surface and the guide inclined surface is A, and 90°<A≤135°;

[0016] And / or, the angle between the wall surface opposite to the boss and the guide bottom surface is B, and A≤B.

[0017] Optionally, the thickness dimension of the plug-in part along a second direction is d, and 0.3mm≤d≤1.2mm.

[0018] Optionally, a thickness dimension of the sealing portion along the second direction is T, and satisfies 0.4 mm ≤ T ≤ 1 mm.

[0019] On the other hand, a battery is further provided, comprising a pole group and a battery housing as described above, wherein the pole group is accommodated in the accommodating chamber.

[0020] Beneficial effects of the present invention:

[0021] The present invention provides a battery case, which includes a cover plate body and an outer shell body. By arranging a boss protruding toward a accommodating chamber on a wall surface where the outer shell body and an inserting portion are in contact, the gap between the assembly chamfer and the outer shell body is narrowed, and larger molten beads are blocked, thereby improving the situation where the molten beads fall into the battery and burn the electrode group and cause a short circuit, thereby improving the safety of use. The shortest straight-line distance e between the boss and the assembly chamfer is limited to meet 0mm<e≤0.2mm, thereby avoiding the gap being too small, which may cause the boss and the cover plate body to collide during assembly and cause interference, and avoiding the gap being too large, which may cause excessively large molten beads to fall into the battery and burn the electrode group and cause a short circuit.

[0022] The present invention provides a battery which, by utilizing the battery shell, improves the situation where molten beads fall into the battery to burn the electrode group and cause short circuit, thereby improving the production yield and effectively controlling the manufacturing cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a partial structural cross-sectional view of the battery housing provided by the present invention after the outer shell body and the cover plate body are welded;

[0024] Figure 2 yes Figure 1 A magnified view of the structure of the middle K part;

[0025] Figure 3 This is a partial structural cross-sectional view of the cover body in the battery housing provided by the present invention;

[0026] Figure 4 It is a partial view of a battery using the battery shell provided by the present invention.

[0027] In the picture:

[0028] 100, welding pool; 101, first melting zone; 102, second melting zone; 103, third melting zone;

[0029] 1. Cover plate body; 11. Closing portion; 12. Insertion portion; 13. Guide portion; 131. Assembly chamfer; 132. Guide bottom surface; 133. Guide slope;

[0030] 2. Shell body; 21. Boss; 22. Groove; 23. First surface; 24. Second surface; 25. Third surface. DETAILED DESCRIPTION

[0031] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It will be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all structures.

[0032] In the description of the present invention, unless otherwise expressly specified or limited, the terms "connected," "connected," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention in specific circumstances.

[0033] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Furthermore, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0034] In the description of this embodiment, the terms "upper," "lower," "right," and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely for ease of description and simplified operation. They do not indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meanings.

[0035] Since a molten pool is formed after the cover plate and the outer shell body are welded, and the molten pool width is generally greater than the molten depth, for the structure in which a step is set on the cover plate and the outer shell body is welded sideways, the direction of the molten pool width is consistent with the direction of the cover plate thickness, so that part of the molten pool is located in the gap between the chamfer of the cover plate and the outer shell body, thereby generating molten beads. Due to the large gap, larger molten beads may fall into the interior of the battery, scalding the electrode group or even causing a short circuit, posing a major safety hazard.

[0036] Therefore, in order to improve the situation where the molten beads fall into the battery and burn the electrode group and cause a short circuit, and to improve the safety of use, this embodiment provides a battery housing.

[0037] like Figures 1 to 4 As shown, the battery case includes a cover body 1 and an outer shell body 2, the cover body 1 includes a closing portion 11, a plug-in portion 12 and a guide portion 13, the plug-in portion 12 is arranged between the closing portion 11 and the guide portion 13, and the guide portion 13 is provided with an assembly chamfer 131 on the side away from the plug-in portion 12. The outer shell body 2 is a hollow shell structure with at least one opening, the plug-in portion 12 and the guide portion 13 are arranged in the outer shell body 2, the closing portion 11 closes the opening of the outer shell body 2 to form a closed accommodating chamber, and the wall surface of the outer shell body 2 and the plug-in portion 12 are in contact with each other, and a boss 21 protruding toward the accommodating chamber is provided. The shortest straight-line distance between the boss 21 and the assembly chamfer 131 is e, and satisfies 0mm<e≤0.2mm.

[0038] The battery case includes a cover body 1 and an outer shell body 2. A boss 21 protruding toward the assembly chamfer 131 is provided on the wall surface where the outer shell body 2 and the plug-in portion 12 are in contact, thereby reducing the gap between the assembly chamfer 131 and the outer shell body 2, blocking larger molten beads, improving the situation where the molten beads fall into the battery and burn the electrode group and cause a short circuit, and improving the safety of use. The shortest straight-line distance e between the boss 21 and the assembly chamfer 131 is limited to meet 0mm<e≤0.2mm, thereby avoiding the gap being too small, which may cause the boss 21 to collide with the cover body 1 during assembly and cause interference, and avoiding the gap being too large, which may cause excessively large molten beads to fall into the battery and burn the electrode group and cause a short circuit.

[0039] In this embodiment, the shortest straight-line distance e between the boss 21 and the assembly chamfer 131 can be any value within the range of 0 mm < e ≤ 0.2 mm or a range between any two values, such as 0.05 mm, 0.1 mm, 0.15 mm, 0.2 mm, etc.

[0040] By adjusting the number of openings of the outer shell body 2, the battery shell can be adapted to different types of batteries. For example, when the outer shell body 2 has only one opening, the battery shell is adapted to square-shell batteries, and only one cover body 1 is provided to correspond thereto. When the outer shell body 2 has two openings, the battery shell is adapted to blade batteries, and two cover bodies 1 are provided to correspond thereto.

[0041] Optionally, the shell body 2 and the cover plate body 1 are welded along the junction of the shell body 2 and the closure 11, and a welding pool 100 is formed, the welding pool 100 including a first molten zone 101 overlapping the shell body 2, a second molten zone 102 overlapping the cover plate body 1, and a third molten zone 103 located in the accommodation cavity, the volume of the third molten zone 103 being V1, and satisfying 0.005mm 3 ≤V1≤0.027mm 3 By limiting the volume of the third molten zone 103, the volume of the third molten zone 103 is prevented from being too large, thereby increasing the probability of generating a bead.

[0042] In order to verify the trapping effect of the boss 21 on the bead and the influence of the limitation of the volume of the third molten zone 103 on the probability of generating a bead, as shown in Table 1, 100 pieces are selected for each group to perform multiple group experiments for verification, and whether the insulation film is scalded and the number of beads appearing is observed.

[0043] Table 1

[0044]

[0045] From Examples 1 to 6, when the volume V1 of the third molten zone 103 satisfies the limited requirement of 0.005mm 3 ≤V1≤0.027mm 3 , the probability of bead occurrence in the same batch of products is less than 30%, and when the shortest straight line distance e between the boss 21 and the assembly chamfer 131 satisfies the limited requirement of 0mm

[0046] From Comparative Examples 1 to 3, when the volume V1 of the third molten zone 103 is greater than the maximum value of the range 0.005mm 3 ≤V1≤0.027mm 3 , the volume of the third molten zone 103 is too large, increasing the probability of bead occurrence, and the probability of bead occurrence in the same batch of products is more than 30%, but since the shortest straight line distance e between the boss 21 and the assembly chamfer 131 satisfies the limited requirement of 0mm

[0047] From Comparative Examples 4 to 6, although the volume V1 of the third molten zone 103 satisfies 0.005mm 3 ≤V1≤0.027mm 3When the limiting requirement is met, the probability of the occurrence of the molten bead of the same batch of products is less than 30%, but since the shortest straight line distance e between the boss 21 and the assembly chamfer 131 is greater than 0mm < e ≤ 0.2mm, the boss 21 cannot achieve the blocking effect on the molten bead, so even if the probability of the occurrence of the molten bead is low, once the molten bead occurs, it will fall into the battery and cause a burn to the insulating film.

[0048] In summary, by limiting the volume V1 of the third melting zone 103 to meet 0.005mm 3 ≤V1≤0.027mm 3 , the probability of the occurrence of the molten bead can be effectively reduced, the shortest straight line distance e between the boss 21 and the assembly chamfer 131 is limited, thereby having a good blocking effect on the molten bead, and the cooperation of the two greatly reduces the probability of product damage caused by the occurrence of the molten bead during welding, and improves the yield of the produced products.

[0049] Optionally, the penetration size of the welding molten pool 100 along the first direction is L1, and satisfies 0.3mm ≤ L1 ≤ 1mm. By limiting the penetration size L1 of the welding molten pool 100 along the first direction, on the one hand, the welding strength is avoided to be too low due to too small penetration, and on the other hand, the cost is wasted and the welding difficulty is increased due to excessive design of too large penetration.

[0050] In the embodiment, the penetration size L1 of the welding molten pool 100 along the first direction can be any value between 0.3mm ≤ L1 ≤ 1mm or a range between any two values, for example, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, etc.

[0051] Optionally, the width size of the welding molten pool 100 along the second direction is L2, and satisfies 0.8mm ≤ L2 ≤ 1.5mm. By limiting the width size L2 of the welding molten pool 100 along the second direction, on the one hand, the covered area is avoided to be too small due to too small width, and the welding strength is too low, and on the other hand, the cost is wasted and the welding difficulty is increased due to excessive design of too large width.

[0052] In the embodiment, the width size L2 of the welding molten pool 100 along the second direction can be any value between 0.8mm ≤ L2 ≤ 1.5mm or a range between any two values, for example, 0.8mm, 0.9mm, 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, etc.

[0053] Optionally, the shell body 2 comprises a first surface 23 located inside the accommodating cavity and a second surface 24 located outside the accommodating cavity, the second surface 24 is recessed in the direction close to the first surface 23, and the first surface 23 forms a boss 21, the second surface 24 forms a groove 22, the depth dimension of the groove 22 along the first direction is a, the thickness dimension of the shell body 2 along the first direction is c, and 0.3≤a / c≤0.8 is satisfied. By limiting the ratio between the depth dimension a of the groove 22 along the first direction and the thickness dimension c of the shell body 2 along the first direction, the depth of the groove 22 is avoided to be too large, thereby reducing the structural strength of the area of the shell body 2 provided with the groove 22, and causing the shell body 2 to be easily torn in the area provided with the groove 22.

[0054] In the embodiment, the thickness dimension of the boss 21 protruding from the second surface 24 is b, since the boss 21 is formed by recessing the second surface 24 in the direction close to the first surface 23, the thickness dimension b of the boss 21 protruding from the second surface 24 satisfies b

[0055] Optionally, the shell body 2 further comprises a third surface 25 abutting against the closed portion 11, the distance dimension between the third surface 25 and the groove 22 along the second direction is h, and h≥1mm is satisfied. By limiting the distance dimension h between the third surface 25 and the groove 22 along the second direction to satisfy h≥1mm, the spacing between the third surface 25 and the groove 22 is avoided to be too short, thereby failing to provide sufficient area for the first melting zone 101 along the second direction.

[0056] Optionally, the guide portion 13 comprises a guide bottom surface 132 parallel to the third surface 25 and a guide inclined surface 133 at an angle with the third surface 25, the angle between the guide bottom surface 132 and the guide inclined surface 133 is A, and 90°

[0057] In the embodiment, the angle A between the guide bottom surface 132 and the guide inclined surface 133 can be any value between 90°

[0058] Optionally, the angle between the wall surface opposite to the guide inclined surface 133 of the boss 21 and the guide bottom surface 132 is B, and A≤B is satisfied. By making the angle B between the wall surface opposite to the guide inclined surface 133 of the boss 21 and the guide bottom surface 132 greater than or equal to the angle A between the guide bottom surface 132 and the guide inclined surface 133, the gap formed between the boss 21 and the assembly chamfer 131 decreases with the depth of the inner part of the accommodation chamber, thereby prolonging the path of the molten bead flow, providing time for the molten bead to cool and solidify, and enhancing the blocking effect of the boss 21 on the molten bead.

[0059] Optionally, the thickness dimension of the insertion part 12 in the second direction is d, and 0.3mm≤d≤1.2mm is satisfied. Since the cover body 1 is mainly inserted and fixed with the inner part of the shell body 2 through the insertion part 12, by limiting the thickness dimension d of the insertion part 12 in the second direction to satisfy 0.3mm≤d≤1.2mm, on the one hand, it avoids that the length of the insertion part 12 is too short, causing the area of the insertion part 12 contacting the shell body 2 to be too small, resulting in low fixing force, which is easy to be popped out during assembly, and on the other hand, it avoids that the length of the insertion part 12 is too long, thereby causing excessive design and occupying more space of the accommodation chamber, resulting in the volume of the pole group being compressed and reducing the power supply capacity of the battery.

[0060] In the embodiment, the thickness dimension d of the insertion part 12 in the second direction can be any value between 0.3mm≤d≤1.2mm or a range between any two values, such as 0.3mm, 0.5mm, 0.7mm, 0.9mm, 1.1mm, 1.2mm, etc.

[0061] Optionally, the thickness dimension of the closed part 11 in the second direction is T, and 0.4mm≤T≤1mm is satisfied. By limiting the thickness dimension T of the closed part 11 in the second direction to satisfy 0.4mm≤T≤1mm, on the one hand, it avoids that the thickness of the closed part 11 is too small, resulting in poor structural strength and easy deformation, and on the other hand, it avoids that the thickness of the closed part 11 is too large, thereby causing excessive design and increasing the overall size of the battery.

[0062] In the embodiment, the thickness dimension T of the closed part 11 in the second direction can be any value between 0.4mm≤T≤1mm or a range between any two values, such as 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, etc.

[0063] In the embodiment, a battery is also provided, which includes a pole group and a battery shell as any one of the above, and the pole group is accommodated in the accommodation chamber. The battery improves the situation that the pole group is scalded and short-circuited due to the molten bead falling into the battery, improves the production yield, and effectively controls the manufacturing cost by using the above-mentioned battery shell.

[0064] Obviously, the above-mentioned embodiments of the present application are only examples for clearly illustrating the present application, and are not intended to limit the implementation of the present application. Various obvious changes, re-adjustments and substitutions can be made by those skilled in the art without departing from the scope of the present application. It is unnecessary and impossible to enumerate all the embodiments here. Any modification, equivalent substitution and improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the claims of the present application.

Claims

1. A battery housing, characterized in that: The battery housing comprises: The cover body comprises a closing portion, an inserting portion and a guiding portion, wherein the inserting portion is provided between the closing portion and the guiding portion, and an assembly chamfer is provided on a side of the guiding portion facing away from the inserting portion; The shell body is a hollow shell structure with at least one opening, the plug-in portion and the guide portion are arranged in the shell body, the closing portion closes the opening of the shell body to form a closed accommodating chamber, and the wall surface of the shell body and the plug-in portion are in contact with each other, and a boss protruding toward the accommodating chamber is provided. The shortest straight-line distance between the boss and the assembly chamfer is e, and satisfies 0mm<e≤0.2mm.

2. The battery case according to claim 1, wherein: The outer shell body and the cover body are welded along the junction of the outer shell body and the closing portion to form a welding pool, wherein the welding pool includes a first melting zone overlapping with the outer shell body, a second melting zone overlapping with the cover body, and a third melting zone located in the accommodating chamber, wherein the volume of the third melting zone is V1 and meets the requirement of 0.005mm 3 ≤V1≤0.027mm 3 .

3. The battery case according to claim 2, characterized in that The penetration depth of the welding pool along the first direction is L1, and satisfies 0.3 mm ≤ L1 ≤ 1 mm.

4. The battery case according to claim 2, wherein: The molten pool has a molten width L2 along the second direction, and satisfies 0.8 mm ≤ L2 ≤ 1.5 mm.

5. The battery case according to claim 1, wherein: The shell body includes a first surface located inside the accommodating chamber and a second surface located outside the accommodating chamber, the second surface is recessed in a direction close to the first surface, and the boss is formed on the first surface, and a groove is formed on the second surface, the depth dimension of the groove along the first direction is a, the thickness dimension of the shell body along the first direction is c, and 0.3≤a / c≤0.8 is satisfied.

6. The battery case according to claim 5, characterized in that The shell body further includes a third surface abutting against the closing portion, and a distance dimension between the third surface and the groove along the second direction is h, and satisfies h≥1 mm.

7. The battery case according to claim 6, characterized in that The guide portion includes a guide bottom surface parallel to the third surface and a guide inclined surface forming an angle with the third surface, wherein the angle between the guide bottom surface and the guide inclined surface is A and satisfies 90°<A≤135°; And / or, the included angle between the wall surface of the boss opposite to the guiding inclined surface and the guiding bottom surface is B, and A≤B is satisfied.

8. The battery case according to claim 1, wherein: The thickness dimension of the plug-in portion along the second direction is d, and satisfies 0.3 mm ≤ d ≤ 1.2 mm.

9. The battery case according to claim 1, characterized in that The thickness of the sealing portion along the second direction is T, and satisfies 0.4 mm ≤ T ≤ 1 mm.

10. A battery, characterized in that The battery comprises a pole group and a battery housing according to any one of claims 1 to 9, wherein the pole group is accommodated in the accommodating chamber.

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