Battery cell and battery pack

Abstract

The utility model relates to the field of batteries, and discloses a battery unit and a battery pack. The battery unit comprises a shell and a cover plate which are connected, and the cover plate is arranged towards a first direction; the pole is connected with the cover plate; the first heat dissipation structure is arranged outside the shell and connected with the pole, the first heat dissipation structure exceeds the side edge of the cover plate and extends towards a second direction to be opposite to the side wall of the shell, and the second direction is opposite to the first direction. The first heat dissipation structure is connected with the pole, the first heat dissipation structure exceeds the side edge of the cover plate and extends in the direction opposite to the direction of the cover plate until the first heat dissipation structure is opposite to the side wall of the shell, heat of the pole can be transmitted to the first heat dissipation structure, the first heat dissipation structure assists the pole in dissipating heat, and therefore the heat dissipation area of the pole can be increased; the heat dissipation efficiency of the pole is improved, the pole is effectively cooled, and the temperature of the battery unit during high-rate charging and discharging is further reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a battery unit and a battery pack. Background Art

[0002] Currently, most battery cells are made of metal. When these battery cells undergo high-rate charge and discharge, they generate significant heat, especially in the column area, where heat accumulation is particularly obvious. This is because the heat dissipation area of ​​the column is relatively limited, which hinders the effective dissipation of heat, causing the temperature of the column to far exceed the temperature of the battery cell body. The heat of the column is easily transferred to the core inside the battery cell, causing the temperature of the core to rise, thereby affecting the life and stability of the battery cell. Utility Model Content

[0003] In view of this, the utility model provides a battery unit and a battery pack to solve the problem in the prior art that heat is easily accumulated in the pole of the battery unit, resulting in a temperature increase.

[0004] In a first aspect, the utility model provides a battery unit, comprising:

[0005] The housing and the cover plate are connected to each other, and the cover plate is arranged in a first direction;

[0006] A pole connected to the cover plate;

[0007] A first heat dissipation structure is arranged outside the shell and connected to the pole. The first heat dissipation structure exceeds the side edge of the cover plate and extends in a second direction to be arranged opposite to the side wall of the shell. The second direction is opposite to the first direction.

[0008] Beneficial effect: The first heat dissipation structure is connected to the pole, which exceeds the side edge of the cover plate and extends in the opposite direction to the cover plate until it is opposite to the side wall of the shell, so that the heat of the pole can be transferred to the first heat dissipation structure, and the first heat dissipation structure assists the pole to dissipate heat, thereby increasing the heat dissipation area of ​​the pole, improving the heat dissipation efficiency of the pole, effectively cooling the pole, and thereby reducing the temperature of the battery cell during high-rate charging and discharging.

[0009] In an optional embodiment, the first heat dissipation structure includes a heat dissipation plate, the heat dissipation plate extends in the second direction, and the heat dissipation plate is arranged opposite to the side wall of the housing.

[0010] Beneficial effects: The heat sink has a simple structure, is easy to process and has low cost.

[0011] In an optional embodiment, the heat dissipation plate includes a corrugated plate, the corrugated plate extends in the second direction, the corrugated plate is arranged opposite to the side wall of the shell, and the wave direction of the corrugated plate is a direction close to or away from the side wall of the shell.

[0012] Beneficial effect: The heat dissipation area of ​​the wave plate is larger, thereby improving the heat dissipation effect and heat dissipation efficiency. For example, when the wave plate is placed in the heat exchange flow channel of the battery pack, the contact area between the wave plate and the heat exchange medium is larger, so the heat exchange efficiency with the heat exchange medium is higher. In addition, by making the wave direction of the wave plate close to or away from the side wall of the shell, the flow resistance of the heat exchange medium will not be increased too much while increasing the contact area between the wave plate and the heat exchange medium.

[0013] In an optional implementation, the first heat dissipation structure further includes a connecting plate, and the connecting plate connects the pole and the heat dissipation plate.

[0014] Beneficial effect: The connection plate is used to transition between the pole and the heat sink, so that the heat sink is connected to the pole through the connection plate.

[0015] In an optional implementation, there is a gap between the first heat dissipation structure and the side wall of the housing.

[0016] Beneficial effect: The first heat dissipation structure can effectively dissipate heat on both the side facing the shell and the side facing away from the shell, thereby increasing the heat dissipation area of ​​the first heat dissipation structure and improving the heat dissipation effect of the first heat dissipation structure. For example, when the first heat dissipation structure is placed in the heat exchange flow channel of the battery pack, both the side facing the shell and the side facing away from the shell of the first heat dissipation structure can contact and exchange heat with the heat exchange medium, so that the contact area between the first heat dissipation structure and the heat exchange medium is larger, and thus the heat exchange efficiency with the heat exchange medium is higher.

[0017] In an optional embodiment, the battery cell further includes an insulating sheet, and the insulating sheet is disposed between the pole core in the outer shell and the inner wall of the outer shell.

[0018] Beneficial effect: It can insulate the pole core from the shell and avoid short circuit between the pole core and the shell.

[0019] In an optional embodiment, the battery unit also includes a second heat dissipation structure, the insulating sheet is provided with a through-hole set through, the second heat dissipation structure covers the through-hole and abuts against the pole core through the through-hole, and the second heat dissipation structure is configured as an insulating structure.

[0020] Beneficial effect: The second heat dissipation structure offsets the pole core, so that the heat of the pole core is transferred to the second heat dissipation structure, and the second heat dissipation mechanism assists the pole core to dissipate heat, thereby increasing the heat dissipation area of ​​the pole core, improving the heat dissipation efficiency of the pole core, and avoiding the problem of heat accumulation in the pole core. At the same time, the second heat dissipation structure is set as an insulating structure, which can also avoid the problem of the pole core being short-circuited with the shell through the second heat dissipation structure.

[0021] In an optional embodiment, at least one of the insulating sheet and the pole core is bonded to the second heat dissipation structure.

[0022] Beneficial effects: It can ensure that the second heat dissipation structure is firmly positioned and not easy to loosen and fall off. In addition, by bonding the pole core to the second heat dissipation structure, the second heat dissipation structure can be tightly connected to the pole core, thereby improving the heat exchange effect between the pole core and the second heat dissipation structure, making it easier for the heat of the pole core to be transferred to the second heat dissipation structure.

[0023] In a second aspect, the utility model further provides a battery pack, comprising a housing and the battery unit as described above, wherein the battery unit is disposed in the housing.

[0024] Beneficial effects: The battery pack includes the battery unit, and also includes all the above advantages of the battery unit, so it will not be described in detail.

[0025] In an optional embodiment, a distance is provided between the side wall of the outer shell and the inner wall of the shell to form a heat exchange channel, the heat exchange channel is used for heat exchange medium to flow, and the first heat dissipation structure extends into the heat exchange channel.

[0026] Beneficial effect: A heat exchange channel is formed between the side wall of the outer shell of the battery cell and the inner wall of the shell of the battery pack. By making the first heat dissipation structure opposite to the side wall of the outer shell, the first heat dissipation structure can extend into the heat exchange channel. When the heat exchange medium flows in the heat exchange channel, it can take away the heat of the first heat exchange structure, thereby improving the heat exchange efficiency between the pole and the heat exchange medium, and further improving the heat dissipation power of the battery cell and reducing the temperature of the battery cell during high-rate charging and discharging. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 A schematic diagram of the structure of a battery unit according to an embodiment of the utility model;

[0029] Figure 2 This is a schematic structural diagram of a first heat dissipation structure of an embodiment of the utility model;

[0030] Figure 3 It is a structural schematic diagram of another first heat dissipation structure of an embodiment of the utility model;

[0031] Figure 4 It is an exploded structural diagram of the second heat dissipation structure and the insulating sheet of the embodiment of the utility model;

[0032] Figure 5 It is a schematic structural diagram of a battery pack according to an embodiment of the utility model.

[0033] Description of reference numerals:

[0034] 1. Shell; 2. Cover plate; 3. Pole; 4. First heat dissipation structure; 401. Heat dissipation plate; 402. Corrugated plate; 403. Connecting plate; 5. Insulating sheet; 501. Through-hole; 6. Pole core; 7. Second heat dissipation structure; 8. Shell; 9. Heat exchange flow channel. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the utility model.

[0036] In the prior art, most battery cell poles are made of metal. When these battery cells undergo high-rate charge and discharge processes, they will generate significant heat, especially in the pole area, where heat accumulation is particularly obvious. This is because the heat dissipation area of ​​the pole is relatively limited, which hinders the effective dissipation of heat, causing the temperature of the pole to far exceed the temperature of the battery cell body. The heat of the pole is easily transferred to the pole core inside the battery cell, causing the temperature of the pole core to rise, thereby affecting the life and stability of the battery cell.

[0037] In order to solve the problem in the prior art that heat easily accumulates and causes the temperature of the pole of the battery unit to rise, a battery unit and a battery pack are provided in an embodiment of the utility model.

[0038] Combine the following Figures 1 to 5 , describing the battery unit provided in an embodiment of the present utility model.

[0039] Specifically, the battery unit includes a housing 1 , a cover plate 2 , a pole 3 and a first heat dissipation structure 4 .

[0040] The housing 1 is connected to the cover plate 2, and the cover plate 2 is arranged in a first direction. Specifically, the interior of the housing 1 is used to accommodate the pole core 6. The housing 1 is provided with an opening for the pole core 6 to pass through, and the opening is arranged in the first direction. The cover plate 2 covers the opening and is connected to the housing 1. Figure 1 As shown, when the battery unit is placed according to the posture shown in the figure, the first direction is the upward direction in the figure.

[0041] The pole 3 is connected to the cover plate 2 , for example, the pole 3 can be clamped with the cover plate 2 through insulating plastic.

[0042] The first heat dissipation structure 4 is arranged outside the housing 1. The first heat dissipation structure 4 is connected to the pole 3. For example, the first heat dissipation structure 4 can be welded to the pole 3, or the first heat dissipation structure 4 and the pole 3 are set as a machined integrated structure, or the first heat dissipation structure 4 and the pole 3 are set as a sheet metal integrated structure. The first heat dissipation structure 4 exceeds the side edge of the cover plate 2 and extends in the second direction to be arranged opposite to the side wall of the housing 1, and the second direction is opposite to the first direction. For example, one end of the first heat dissipation structure 4 is connected to the pole 3, and the other end of the first heat dissipation structure 4 exceeds the side edge of the cover plate 2 and extends in the second direction. The first heat dissipation structure 4 extends to be arranged opposite to the side wall of the housing 1. Specifically, the end of the first heat dissipation structure 4 facing away from the pole 3 is arranged opposite to the side wall of the housing 1.

[0043] It should be noted that the first direction can also be Figure 1 The second direction is the downward direction, that is, the state when the battery unit is placed upside down. Figure 1 In the upward direction.

[0044] It should be noted that the side wall of the shell 1 refers to any one of the two large faces and two side faces of the shell 1. When the battery cells in the battery pack are arranged in a large face-to-large face stacking manner, the side wall of the shell 1 is the side face of the shell 1; when the battery cells in the battery pack are arranged in a side-to-side stacking manner, the side wall of the shell 1 is the large face of the shell 1.

[0045] In this embodiment, the first heat dissipation structure 4 is connected to the pole 3. The first heat dissipation structure 4 exceeds the side edge of the cover plate 2 and extends in the opposite direction to the cover plate 2 until it is opposite to the side wall of the shell 1, so that the heat of the pole 3 can be transferred to the first heat dissipation structure 4, and the first heat dissipation structure 4 assists the pole 3 to dissipate heat, thereby increasing the heat dissipation area of ​​the pole 3, improving the heat dissipation efficiency of the pole 3, effectively cooling the pole 3, and thereby reducing the temperature of the battery cell during high-rate charging and discharging.

[0046] In addition, refer to Figure 5As shown, when the battery cells are assembled into a battery pack, a heat exchange channel 9 is formed between the side wall of the outer shell 1 of the battery cell and the inner wall of the shell 8 of the battery pack. By making the first heat dissipation structure 4 opposite to the side wall of the outer shell 1, the first heat dissipation structure 4 can extend into the heat exchange channel 9. When the heat exchange medium flows in the heat exchange channel 9, it can take away the heat of the first heat exchange structure 4, thereby improving the heat exchange efficiency between the pole 3 and the heat exchange medium, and further improving the heat dissipation power of the battery cell and reducing the temperature of the battery cell during high-rate charge and discharge.

[0047] refer to Figure 2 As shown, in some embodiments provided by the present invention, the first heat dissipation structure 4 includes a heat dissipation plate 401, which extends in the second direction and is arranged opposite to the side wall of the housing 1. With such arrangement, the heat dissipation plate 401 has a simple structure, is easy to process, and has low cost.

[0048] refer to Figure 3 As shown, in some embodiments provided by the present invention, the heat sink 401 includes a wave plate 402. The wave plate 402 extends in the second direction, the wave plate 402 is arranged opposite to the side wall of the housing 1, and the wave direction of the wave plate 402 is the direction close to or away from the side wall of the housing 1.

[0049] In this embodiment, by providing the wave plate 402, the heat dissipation area of ​​the wave plate 402 is larger, thereby improving the heat dissipation effect and heat dissipation efficiency. For example, when the wave plate 402 is placed in the heat exchange flow channel 9 of the battery pack, the contact area between the wave plate 402 and the heat exchange medium is larger, so the heat exchange efficiency with the heat exchange medium is higher. In addition, by making the wave direction of the wave plate 402 close to or away from the side wall of the housing 1, the flow resistance of the heat exchange medium can be increased without excessively increasing the contact area between the wave plate 402 and the heat exchange medium.

[0050] In some embodiments provided by the utility model, the first heat dissipation structure 4 further includes a connecting plate 403, and the connecting plate 403 connects the pole 3 and the heat sink 401. For example, the connecting plate 403 is welded to the heat sink 401, or the connecting plate 403 and the heat sink 401 are set as a machined integrated structure, or the connecting plate 403 and the heat sink 401 are set as a sheet metal integrated structure. The connecting plate 403 is used to transition between the pole 3 and the heat sink 401, so that the heat sink 401 is connected to the pole 3 through the connecting plate 403.

[0051] Optionally, a rounded corner is provided to smoothly transition between the connecting plate 403 and the heat dissipation plate 401 to reduce the problem of stress concentration between the connecting plate 403 and the heat dissipation plate 401 .

[0052] In some embodiments provided by the utility model, there is a gap between the first heat dissipation structure 4 and the side wall of the shell 1. By having a gap between the first heat dissipation structure 4 and the side wall of the shell 1, the first heat dissipation structure 4 can effectively dissipate heat on the side facing the shell 1 and the side facing away from the shell 1, thereby increasing the heat dissipation area of ​​the first heat dissipation structure 4 and improving the heat dissipation effect of the first heat dissipation structure 4. For example, when the first heat dissipation structure 4 is placed in the heat exchange flow channel 9 of the battery pack, the side of the first heat dissipation structure 4 facing the shell 1 and the side facing away from the shell 1 can both contact and exchange heat with the heat exchange medium, so that the contact area between the first heat dissipation structure 4 and the heat exchange medium is larger, and thus the heat exchange efficiency with the heat exchange medium is higher.

[0053] refer to Figure 4 As shown, in some embodiments provided by the present invention, the battery cell further includes an insulating sheet 5, which is disposed between the pole core 6 in the shell 1 and the inner wall of the shell 1. By disposing the insulating sheet 5 between the pole core 6 and the shell 1, the pole core 6 and the shell 1 can be insulated to avoid a short circuit between the pole core 6 and the shell 1.

[0054] Optionally, the insulating sheet 5 is configured as a Mylar sheet.

[0055] refer to Figure 4 As shown, in some embodiments provided by the present utility model, the battery unit further includes a second heat dissipation structure 7. A through hole 501 is provided on the insulating sheet 5, the second heat dissipation structure 7 covers the through hole 501, and abuts against the pole core 6 through the through hole 501, and the second heat dissipation structure 7 is provided as an insulating structure.

[0056] Since the insulating sheet 5 is usually made of plastic, the heat dissipation performance is poor, so that the heat of the pole core 6 is not easy to dissipate through the insulating sheet 5, resulting in the heat easily accumulating in the pole core 6. In this embodiment, by setting a through hole 501 on the insulating sheet 5 and covering the through hole 501 with the second heat dissipation structure 7, the second heat dissipation structure 7 and the pole core 6 are offset, so that the heat of the pole core 6 can be transferred to the second heat dissipation structure 7, and the second heat dissipation mechanism assists the pole core 6 to dissipate heat, thereby increasing the heat dissipation area of ​​the pole core 6, improving the heat dissipation efficiency of the pole core 6, and avoiding the problem of heat accumulation in the pole core 6. At the same time, the second heat dissipation structure 7 is set as an insulating structure, which can also avoid the problem of the pole core 6 being short-circuited with the housing 1 through the second heat dissipation structure 7.

[0057] Optionally, the material of the second heat dissipation structure 7 includes but is not limited to aluminum oxide, graphene, silica gel, aluminum nitride and boron nitride.

[0058] Optionally, the thickness of the second heat dissipation structure 7 ranges from 0.05 mm to 3 mm. If the thickness is less than 0.05 mm, the strength of the second heat dissipation structure 7 is poor and it is easy to break; if the thickness is greater than 3 mm, the weight of the second heat dissipation structure 7 increases, the cost increases, and the thermal conductivity effect decreases. Therefore, when the thickness of the second heat dissipation structure 7 is between 0.05 mm and 3 mm, it can not only ensure the strength of the second heat dissipation structure 7 and avoid the problem of its breakage, but also ensure the heat dissipation effect of the second heat dissipation structure 7, reducing the weight and cost of the second heat dissipation structure 7.

[0059] Optionally, the shape of the through opening 501 includes but is not limited to circle, ellipse, triangle or rectangle. Accordingly, the shape of the second heat dissipation structure 7 matches the shape of the through opening 501 , but the area of ​​the second heat dissipation structure 7 is larger than that of the through opening 501 .

[0060] Optionally, at least two opposite sides of the insulating sheet 5 are provided with through openings 501, and each through opening 501 is blocked by a corresponding second heat dissipation structure 7. In this way, the pole core can dissipate heat simultaneously through the second heat dissipation structures 7 on both sides, thereby improving the heat dissipation efficiency of the pole core.

[0061] In some embodiments provided by the present invention, at least one of the insulating sheet 5 and the pole core 6 is bonded to the second heat dissipation structure 7. Such a configuration can ensure that the second heat dissipation structure 7 is firmly positioned and not easily loosened or dropped. In addition, by bonding the pole core 6 to the second heat dissipation structure 7, the second heat dissipation structure 7 can be closely connected to the pole core 6, thereby improving the heat exchange effect between the pole core 6 and the second heat dissipation structure 7, and making it easier for the heat of the pole core 6 to be transferred to the second heat dissipation structure 7.

[0062] Optionally, the pole core 6 may be bonded to the second heat dissipation structure 7 by means of a thermally conductive adhesive.

[0063] refer to Figure 5 As shown, a battery pack is also provided in the embodiment of the utility model.

[0064] Specifically, the battery pack includes a housing 8 and the battery cells described above. The battery cells are disposed in the housing 8 .

[0065] It should be noted that the battery pack includes the battery cell, and also includes all the above advantages of the battery cell, so it will not be elaborated on here.

[0066] refer to Figure 5 As shown, in some embodiments provided by the present utility model, there is a distance between the side wall of the shell 1 and the inner wall of the shell 8 to form a heat exchange channel 9, the heat exchange channel 9 is used for the circulation of heat exchange medium, and the first heat dissipation structure 4 extends into the heat exchange channel 9.

[0067] In this embodiment, a heat exchange channel 9 is formed between the side wall of the outer shell 1 of the battery cell and the inner wall of the shell 8 of the battery pack. By making the first heat dissipation structure 4 opposite to the side wall of the outer shell 1, the first heat dissipation structure 4 can extend into the heat exchange channel 9. When the heat exchange medium flows in the heat exchange channel 9, it can take away the heat of the first heat exchange structure 4, thereby improving the heat exchange efficiency between the pole 3 and the heat exchange medium, and further improving the heat dissipation power of the battery cell and reducing the temperature of the battery cell during high-rate charging and discharging.

[0068] Although the embodiments of the present invention are described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A battery cell, characterized in that: include: The housing (1) and the cover plate (2) are connected to each other, and the cover plate (2) is arranged in a first direction; A pole (3) connected to the cover plate (2); A first heat dissipation structure (4) is arranged outside the housing (1) and connected to the pole (3); the first heat dissipation structure (4) exceeds the side edge of the cover plate (2) and extends in a second direction to be arranged opposite to the side wall of the housing (1); the second direction is opposite to the first direction.

2. The battery cell according to claim 1, characterized in that: The first heat dissipation structure (4) comprises a heat dissipation plate (401), the heat dissipation plate (401) extends in the second direction, and the heat dissipation plate (401) is arranged opposite to a side wall of the housing (1).

3. The battery cell according to claim 2, characterized in that: The heat dissipation plate (401) comprises a wave plate (402), the wave plate (402) extends in the second direction, the wave plate (402) is arranged opposite to the side wall of the housing (1), and the wave direction of the wave plate (402) is a direction approaching or moving away from the side wall of the housing (1).

4. The battery cell according to claim 2, characterized in that: The first heat dissipation structure (4) further comprises a connecting plate (403), wherein the connecting plate (403) connects the pole (3) and the heat dissipation plate (401).

5. The battery cell according to claim 1, characterized in that: There is a gap between the first heat dissipation structure (4) and the side wall of the housing (1).

6. The battery cell according to any one of claims 1 to 5, characterized in that: The battery unit further comprises an insulating sheet (5), wherein the insulating sheet (5) is arranged between the pole core (6) in the outer shell (1) and the inner wall of the outer shell (1).

7. The battery cell according to claim 6, characterized in that: The battery unit further comprises a second heat dissipation structure (7); a through hole (501) is provided on the insulating sheet (5); the second heat dissipation structure (7) covers the through hole (501) and abuts against the pole core (6) through the through hole (501); the second heat dissipation structure (7) is configured as an insulating structure.

8. The battery cell according to claim 7, characterized in that: At least one of the insulating sheet (5) and the pole core (6) is bonded to the second heat dissipation structure (7).

9. A battery pack, characterized in that: It comprises a housing (8) and a battery unit according to any one of claims 1 to 8, wherein the battery unit is arranged in the housing (8).

10. The battery pack according to claim 9, characterized in that: There is a distance between the side wall of the outer shell (1) and the inner wall of the shell (8) to form a heat exchange channel (9), the heat exchange channel (9) is used for heat exchange medium to flow, and the first heat dissipation structure (4) extends into the heat exchange channel (9).

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