Busbar cooling structure and battery pack

Abstract

The utility model relates to the technical field of batteries, and discloses a busbar cooling structure and a battery pack, and the busbar cooling structure comprises an insulating sheet and a heat dissipation assembly, one surface of the insulating sheet is suitable for being fixedly attached to the busbar; the heat dissipation assembly comprises a connecting plate and a plurality of cooling fins which are connected, the connecting plate is fixedly attached to the other opposite face of the insulating sheet, and the cooling fins are arranged on the side, away from the insulating sheet, of the connecting plate at intervals and form an angle with the connecting plate. According to the utility model, the insulating sheet is fixedly attached to the busbar, the insulating sheet can prevent short circuit between the busbar and the outside, and can provide an attachment basis for the heat dissipation assembly to ensure the structural stability of the heat dissipation assembly, the connecting plate of the heat dissipation assembly is fixedly connected with the insulating sheet, and the heat dissipation area is enlarged by using the plurality of heat dissipation sheets; the heat of the busbar is quickly diffused to the surrounding environment, so that the temperature of the busbar is quickly reduced, the damage to the battery pack caused by overheating of the busbar is avoided, the service life of the battery pack is prolonged, and the use safety of the battery pack is improved.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, specifically to a busbar cooling structure and a battery pack. Background Technology

[0002] Currently, battery packs are gradually developing towards high-rate fast charging, which means a larger charging current. The terminals of the individual cells within a battery pack are generally electrically connected via busbars.

[0003] According to Joule's law, when the current increases significantly, the heat generated will increase quadratically, given a fixed bus resistance and charging time. Furthermore, the bus itself has resistance, including its internal resistance and the contact resistance at the connection point with the battery cell terminals. During high-rate fast charging, the large current flowing through the bus converts electrical energy into heat, causing the bus to overheat. This, in turn, raises the temperature at the battery cell terminals, reducing cell capacity and charging / discharging efficiency, ultimately shortening the battery pack's lifespan and compromising safety. Utility Model Content

[0004] In view of this, the present invention provides a busbar cooling structure and a battery pack to solve the problem that the busbar of the existing battery pack is prone to overheating, resulting in a shorter battery pack life and poorer safety.

[0005] In a first aspect, this utility model provides a busbar cooling structure, comprising:

[0006] The insulating sheet has one side adapted to be fixedly attached to the busbar;

[0007] A heat dissipation assembly includes a connecting plate and a plurality of heat sinks connected to each other. The connecting plate is fixedly attached to the opposite side of the insulating sheet. The plurality of heat sinks are spaced apart on the side of the connecting plate away from the insulating sheet and are set at an angle to the connecting plate.

[0008] Beneficial effects: This invention fixes an insulating sheet onto the busbar. The insulating sheet prevents short circuits between the busbar and the external environment, ensuring the electrical safety of the battery pack. It also provides a flat and stable base for the heat dissipation assembly, ensuring a secure connection between the heat dissipation assembly and the busbar. The insulating sheet also supports the busbar, improving its structural stability. The connecting plate of the heat dissipation assembly is fixedly connected to the insulating sheet. The multiple heat dissipation fins of the heat dissipation assembly expand the heat dissipation area, rapidly dissipating the heat from the busbar to the surrounding environment. This quickly dissipates the heat from the busbar, maintaining it within a suitable operating temperature range, preventing overheating and damage to the battery pack, and thus improving the battery pack's lifespan and operational safety.

[0009] Furthermore, the busbar itself does not require a cooling structure, reducing its installation volume and thus improving the space utilization of the battery pack and lowering operating costs. Multiple heat sinks can also buffer impacts, preventing collision energy from directly affecting the busbar and battery cells, further enhancing the safety of the battery pack.

[0010] In one alternative embodiment, the surface of the heat sink is provided with an insulating layer.

[0011] Beneficial effects: Heat sinks are usually made of metals with high thermal conductivity. By setting an insulating layer on the surface of the heat sink, it is possible to prevent the heat sink from coming into contact with other components in the battery pack and causing a short circuit.

[0012] In one alternative embodiment, the surface of the heat sink is at least partially coated with a thermal expansion coating.

[0013] Beneficial effects: Coating at least part of the surface of the heat sink with a thermal expansion coating can cause the thermal expansion coating to expand when thermal runaway occurs in the battery pack, filling the space between multiple heat sinks, reducing the heat conduction area and heat exchange capacity, thereby achieving further protection for the battery cell.

[0014] In one alternative embodiment, a plurality of the heat sinks are arranged perpendicularly to the connecting plate.

[0015] Beneficial effects: The heatsink is positioned perpendicularly to the connecting plate, resulting in a more direct heat conduction path. This facilitates the even dissipation of heat from both sides of the heatsink, preventing heat buildup between the fins. The vertically arranged heatsink also improves airflow, removing heat more efficiently.

[0016] In one alternative embodiment, the thickness T of the heat sink is ≤ 2 mm.

[0017] Beneficial effects: By limiting the thickness of the heat sink to less than or equal to 2mm, the weight of the heat sink can be reduced, enabling a lightweight design of the battery pack.

[0018] Secondly, this utility model also provides a battery pack, comprising:

[0019] The shell has an internal cavity;

[0020] Multiple battery cells are disposed within the receiving cavity, and each battery cell has an electrode post on one side, the electrode post being connected to a busbar;

[0021] The aforementioned busbar cooling structure is located within the receiving cavity, with one side of the insulating sheet fixedly attached to the busbar, and a heat dissipation channel is provided between the heat dissipation component and the housing.

[0022] Beneficial effects: Because the battery pack includes a busbar cooling structure, it has the same effect as the busbar cooling structure. The insulating sheet is fixedly attached to the busbar, which prevents short circuits between the busbar and the external environment, ensuring the electrical safety of the battery pack. It also provides a flat and stable base for the heat dissipation components, ensuring a secure connection between the heat dissipation components and the busbar. The insulating sheet also supports the busbar, improving its structural stability. The connecting plate of the heat dissipation component is connected and fixed to the insulating sheet. The multiple heat sinks of the heat dissipation component expand the heat dissipation area, quickly dissipating the heat from the busbar to the surrounding environment, thus maintaining the busbar within a suitable operating temperature range. This prevents overheating of the busbar from damaging the battery pack, improving battery pack lifespan and operational safety.

[0023] Furthermore, the busbar itself does not require a cooling structure, reducing its installation volume and thus improving the space utilization of the battery pack and lowering operating costs. Multiple heat sinks can also buffer impacts, preventing collision energy from directly affecting the busbar and battery cells, further enhancing the safety of the battery pack.

[0024] In one optional embodiment, in the height direction of the housing, the dimensions of the pole L1, the busbar L2, the insulating sheet L3, and the height of the heat dissipation assembly L4 satisfy the following: L3>L4>L2>L1.

[0025] Beneficial effects: The insulation sheet has the largest height dimension to prevent short circuits between the busbar and the outside environment. The height dimension of the busbar is larger than that of the terminal post to cover the terminal post and achieve effective electrical connection between adjacent cell terminals. At the same time, it has a larger heat dissipation area. The height dimension of the heat dissipation component is larger than that of the busbar to provide a larger heat dissipation area and improve the heat dissipation effect of the busbar.

[0026] In one alternative implementation, the height of the plurality of heat sinks is greater than the height of the busbar.

[0027] Beneficial effects: Because multiple heat sinks are spaced apart, both opposite sides of the heat sinks can be used for heat dissipation. By setting the height of multiple heat sinks to be greater than the height of the busbar, at least twice the heat dissipation area of ​​the original busbar can be provided, thereby significantly improving the heat dissipation effect of the busbar.

[0028] In one optional embodiment, the housing is provided with a cooling plate, and the heat dissipation assembly is further provided with a contact portion that contacts the cooling plate, and the contact portion is connected to the connecting plate.

[0029] Beneficial effects: The heat dissipation component is designed to contact the cooling plate, which allows the cooling plate inside the housing to dissipate heat from the battery cell, thereby improving the temperature control effect of the busbar.

[0030] In one alternative embodiment, the housing is further provided with a fan facing the heat dissipation channel.

[0031] Beneficial effects: By installing a fan inside the housing that faces the heat dissipation channel, forced convection can be achieved in the heat dissipation channel. The fan guides the airflow direction in the heat dissipation channel, quickly blowing out hot air and further improving the heat dissipation effect of the busbar. Attached Figure Description

[0032] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0033] Figure 1 This is a schematic diagram of the structure of a battery pack according to an embodiment of the present utility model;

[0034] Figure 2 for Figure 1 Cross-sectional view at point AA;

[0035] Figure 3 for Figure 2 A magnified view of a portion of the image;

[0036] Figure 4 This is a partial structural diagram of a battery pack according to an embodiment of the present utility model;

[0037] Figure 5 This is a schematic diagram showing the connection between the battery cell and the busbar cooling structure of a battery pack according to an embodiment of the present invention.

[0038] Figure 6 This is a schematic diagram showing the connection between the battery cell and the busbar of a battery pack according to an embodiment of the present invention.

[0039] Explanation of reference numerals in the attached figures:

[0040] 1. Insulating sheet; 2. Heat dissipation assembly; 201. Connecting plate; 202. Heat sink; 203. Contact part; 3. Housing; 301. Receiving cavity; 302. Cooling plate; 4. Battery cell; 401. Terminal; 5. Busbar; 6. Heat dissipation channel; 7. Fan. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, 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.

[0042] Poor busbar material, excessively small cross-sectional area, and connection process issues can all increase busbar resistance and exacerbate overheating. During high-rate fast charging of the battery pack, issues such as the inconsistency of individual cells may lead to uneven current distribution on the busbar, resulting in excessively high current density in some areas. This causes these areas to generate more heat, leading to severe busbar overheating.

[0043] The heat generated by the busbar will increase the temperature of the cell terminal area, accelerating the decomposition of the positive electrode binder, irreversible phase transition, and dissolution of transition metal elements. The negative electrode side of the cell will consume the limited active lithium inside the battery, resulting in irreversible capacity loss and a decrease in the overall capacity of the battery.

[0044] Excessive temperatures can alter the rate of chemical reactions within the battery cell and affect the performance of electrode materials, leading to reduced charge and discharge efficiency. During charging, it takes longer to reach full charge, and during discharge, the output current and voltage may be unstable. Furthermore, high temperatures accelerate the aging and damage of internal battery materials, reducing the battery's cycle life. If the busbar continues to heat up, the accumulated heat within the battery pack can easily trigger thermal runaway, leading to serious safety incidents such as fires and explosions.

[0045] Therefore, a cooling structure is needed for the busbar to quickly dissipate heat and protect the battery pack.

[0046] The following is combined with Figures 1 to 6 The following describes embodiments of the present invention.

[0047] According to embodiments of the present invention, on the one hand, such as Figures 1 to 3 As shown, a busbar cooling structure is provided, mainly including: an insulating sheet 1 and a heat dissipation assembly 2. One side of the insulating sheet 1 is adapted to be fixedly attached to the busbar 5. The heat dissipation assembly 2 includes a connecting plate 201 and a plurality of heat dissipation fins 202 connected to each other. The connecting plate 201 is fixedly attached to the opposite side of the insulating sheet 1, and the plurality of heat dissipation fins 202 are spaced apart on the side of the connecting plate 201 away from the insulating sheet 1 and are arranged at an angle to the connecting plate 201.

[0048] Therefore, the bus cooling structure provided in this embodiment of the present invention, with an insulating sheet 1 fixedly attached to the bus 5, can prevent the bus 5 from short-circuiting with the outside world, ensuring the electrical safety of the battery pack and avoiding safety hazards such as cell 4 failure and fire caused by accidental short circuits. The insulating sheet 1 also provides a flat and stable attachment base for the heat dissipation assembly 2, ensuring that the heat dissipation assembly 2 can be firmly connected to the bus 5. The insulating sheet 1 can also support the bus 5, improving the structural stability of the bus 5. The connecting plate 201 of the heat dissipation assembly 2 is connected and fixed to the insulating sheet 1. The multiple heat dissipation fins 202 of the heat dissipation assembly 2 can expand the heat dissipation area. The heat dissipation fins 202 have a large contact area with the surrounding air, which can quickly diffuse the heat of the bus 5 to the surrounding environment, thereby quickly dissipating the heat of the bus 5 and maintaining the bus 5 within a suitable operating temperature. This prevents the bus 5 from overheating and damaging the battery pack, and helps to improve the service life and safety of the battery pack. Under high-load conditions such as high-rate fast charging, the battery pack can maintain high charging and discharging efficiency and reduce the rate of capacity decay.

[0049] Furthermore, the busbar 5 itself does not require a heat dissipation structure. Compared to the traditional method of increasing the cross-sectional area of ​​the busbar 5 to improve heat dissipation, this embodiment of the invention meets the heat dissipation requirements of the busbar 5 while reducing its installation volume, thereby improving the space utilization of the battery pack and reducing usage costs, achieving a lightweight design and compact layout. Multiple heat sinks 202 can also buffer collisions, preventing collision energy from directly acting on critical and relatively fragile components such as the busbar 5 and the battery cell 4, thereby reducing the risk of short circuits, fires, and damage to the battery cell 4 caused by collisions, further improving the safety of the battery pack.

[0050] Effective heat dissipation of busbar 5 allows for better coordination among the various components within the battery pack. Overheating of busbar 5 no longer affects the normal operation of connected cells 4 and other electrical components, thereby improving the overall reliability and stability of the battery pack and ensuring the stable operation of devices such as electric vehicles equipped with the battery pack.

[0051] It should be noted that this embodiment of the utility model does not limit the fixing and bonding method of the insulating sheet 1 and the busbar 5. Any existing method can be selected as needed. For example, the insulating sheet 1 can be bonded and fixed to the busbar 5 with adhesive, resulting in a tight connection.

[0052] Furthermore, this embodiment of the invention does not limit the material of the heat sink 202, as long as the heat sink 202 can achieve effective heat dissipation. Specifically, the heat sink 202 can be made of a material with a thermal conductivity greater than 150 W / (mk), such as aluminum alloy, copper, etc. The heat sink 202 can be manufactured using a pultrusion molding process.

[0053] In one embodiment, the surface of the heat sink 202 is provided with an insulating layer. The heat sink 202 is typically made of a metal with high thermal conductivity. By providing an insulating layer on the surface of the heat sink 202, it is possible to prevent the heat sink 202 from coming into contact with other components in the battery pack and causing a short circuit. The insulating layer can be a conventional insulating layer such as a polyvinyl chloride layer, a polyimide layer, or a polytetrafluoroethylene layer.

[0054] In one embodiment, the surface of the heat sink 202 is at least partially coated with a thermal expansion coating. Coating the surface of the heat sink 202 with this thermal expansion coating allows the coating to expand due to heat in the event of thermal runaway in the battery pack, filling the space between the multiple heat sinks 202, reducing the thermal conductivity area and heat exchange capacity, thereby providing further protection for the battery cell 4. The thermal expansion coating can be a silicon-based coating, a ceramic coating, or the like.

[0055] In one embodiment, such as Figure 3 As shown, multiple heat sinks 202 are arranged perpendicularly to the connecting plate 201. This perpendicular arrangement of the heat sinks 202 and the connecting plate 201 results in a more direct heat conduction path, facilitating the even dissipation of heat from both sides of the heat sinks 202 and preventing heat accumulation between them. The vertically arranged heat sinks 202 also improve airflow, more efficiently removing heat.

[0056] In one embodiment, such as Figure 3 As shown, the thickness T of the heat sink 202 is ≤ 2mm. By limiting the thickness of the heat sink 202 to less than or equal to 2mm, the weight of the heat sink 202 can be reduced, achieving a lightweight design for the battery pack.

[0057] According to an embodiment of the present invention, on the other hand, as... Figure 1 and Figure 2 As shown, a battery pack is also provided, mainly including: a housing 3, multiple battery cells 4, and a busbar cooling structure. The housing 3 has an internal receiving cavity 301. Multiple battery cells 4 are disposed within the receiving cavity 301, and each battery cell 4 has a terminal post 401 on one side, which is connected to a busbar 5. The busbar cooling structure is disposed within the receiving cavity 301, with one side of the insulating sheet 1 fixedly attached to the busbar 5, and a heat dissipation channel 6 is provided between the heat dissipation assembly 2 and the housing 3.

[0058] Because the battery pack includes a busbar cooling structure, which has the same effect as the busbar cooling structure, an insulating sheet 1 is fixedly attached to the busbar 5. The insulating sheet 1 can prevent the busbar 5 from short-circuiting with the outside world, ensuring the electrical safety of the battery pack and avoiding safety hazards such as cell 4 failure and fire caused by accidental short circuits. The insulating sheet 1 can also provide a flat and stable attachment base for the heat dissipation component 2, ensuring that the heat dissipation component 2 can be firmly connected to the busbar 5. The insulating sheet 1 can also support the busbar 5 and improve the structural stability of the busbar 5. The connecting plate 201 of the heat dissipation component 2 is connected and fixed to the insulating sheet 1. The multiple heat dissipation fins 202 of the heat dissipation component 2 can expand the heat dissipation area. The heat dissipation fins 202 have a large contact area with the surrounding air, which can quickly dissipate the heat of the busbar 5 to the surrounding environment, thereby quickly dissipating the heat of the busbar 5 and maintaining the busbar 5 within a suitable operating temperature. This prevents the busbar 5 from overheating and damaging the battery pack, which is beneficial to improving the service life and safety of the battery pack. Under high-load conditions such as high-rate fast charging, the battery pack can maintain high charging and discharging efficiency and reduce the rate of capacity decay.

[0059] Furthermore, the busbar 5 itself does not require a heat dissipation structure, reducing its installation volume and thus improving the space utilization of the battery pack and lowering operating costs. Multiple heat sinks 202 also buffer impacts, preventing collision energy from directly impacting the busbar 5 and the battery cell 4, further enhancing the safety of the battery pack.

[0060] Specifically, such as Figure 5 and Figure 6 As shown, multiple battery cells 4 are arranged in a row, and the terminals 401 of adjacent battery cells 4 are electrically connected through a busbar 5. The terminals 401 and the busbar 5 can be fixed by welding, ensuring a firm connection. The multiple battery cells 4 are also fixedly connected through a busbar cooling structure, improving the installation stability of the multiple battery cells 4 within the battery pack. The insulating sheet 1 can extend to the housing 3 and connect with the housing 3, forming a heat dissipation channel between the insulating sheet 1 and the housing 3.

[0061] In addition, multiple rows of battery cells 4 can be arranged inside the receiving cavity 301. When the busbars 5 of multiple battery cells 4 are distributed in opposite directions, there is a gap between the relative heat dissipation components 2 of the rows of battery cells 4, and a heat dissipation channel 6 is formed between the relative insulating sheets 1.

[0062] In one embodiment, such as Figure 3 As shown, in the height direction of the housing 3, the dimensions of the pole post 401 (L1), the busbar 5 (L2), the insulating sheet 1 (L3), and the heat dissipation assembly 2 (L4) satisfy the following order: L3>L4>L2>L1. The height direction of the housing 3 is as follows... Figure 3As indicated by arrow H in the diagram, the insulating sheet 1 has the largest height to prevent short circuits between the busbar 5 and the outside environment. The height of the busbar 5 is greater than that of the terminal 401 to cover the terminal 401, achieving effective electrical connection between the terminals 401 of adjacent cells 4, and also providing a larger heat dissipation area. The height of the heat dissipation component 2 is greater than that of the busbar 5 to provide an even larger heat dissipation area and improve the heat dissipation effect of the busbar 5.

[0063] In one embodiment, the sum of the heights of the multiple heat sinks 202 is greater than the height of the busbar 5. Since the multiple heat sinks 202 are spaced apart, both opposite sides of the heat sinks 202 can be used for heat dissipation. By setting the sum of the heights of the multiple heat sinks 202 to be greater than the height of the busbar 5, and the length of the heat sinks 202 to be greater than the length of the busbar 5, at least twice the heat dissipation area of ​​the original busbar 5 can be provided, thereby significantly improving the heat dissipation effect of the busbar 5.

[0064] In one embodiment, such as Figure 3 As shown, a cooling plate 302 is provided inside the housing 3, and the heat dissipation assembly 2 is also provided with a contact part 203 that contacts the cooling plate 302. The contact part 203 is connected to the connecting plate 201. The heat dissipation assembly 2 is provided with a contact part 203 that contacts the cooling plate 302, so that the cooling plate 302 inside the housing 3 can dissipate heat for the heat dissipation assembly 2, thereby improving the temperature control effect of the busbar 5.

[0065] Specifically, such as Figure 3 As shown, one end of the connecting plate 201 is bent to form a contact portion 203, which is attached to the inner side of the cooling plate 302. Alternatively, the heat sink 202 located at the end is attached to the cooling plate 302, and the heat sink 202 also serves as the contact portion 203.

[0066] In one embodiment, such as Figure 4 As shown, the housing 3 also includes a fan 7 facing the heat dissipation channel 6. By installing the fan 7 facing the heat dissipation channel 6 inside the housing 3, forced convection can be achieved in the heat dissipation channel 6. The fan 7 guides the airflow direction within the heat dissipation channel, quickly blowing out hot air and further improving the heat dissipation effect of the manifold 5. When multiple heat dissipation channels 6 are provided, multiple fans 7 are provided corresponding to each heat dissipation channel 6.

[0067] To achieve the basic functions of the battery pack, the battery pack in this embodiment may also include other necessary modules or components, such as a battery control system and a battery thermal management system. It should be noted that any suitable existing structure can be selected for the other necessary modules or components included in the battery pack. To clearly and concisely illustrate the technical solution provided in this embodiment, the above-mentioned parts will not be repeated here, and the accompanying drawings have also been simplified accordingly. However, it should be understood that the scope of the embodiments of this utility model is not limited thereto.

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

Claims

1. A busbar cooling structure, characterized in that, include: The insulating sheet has one side adapted to be fixedly attached to the busbar; A heat dissipation assembly includes a connecting plate and a plurality of heat sinks connected to each other. The connecting plate is fixedly attached to the opposite side of the insulating sheet. The plurality of heat sinks are spaced apart on the side of the connecting plate away from the insulating sheet and are set at an angle to the connecting plate.

2. The busbar cooling structure according to claim 1, characterized in that, The surface of the heat sink is provided with an insulating layer.

3. The busbar cooling structure according to claim 1, characterized in that, The surface of the heat sink is at least partially coated with a thermal expansion coating.

4. The busbar cooling structure according to claim 1, characterized in that, The heat sinks are arranged perpendicularly to the connecting plate.

5. The busbar cooling structure according to any one of claims 1 to 4, characterized in that, The thickness T of the heat sink is ≤ 2mm.

6. A battery pack, characterized in that, include: The shell has an internal cavity; Multiple battery cells are disposed within the receiving cavity, and each battery cell has an electrode post on one side, the electrode post being connected to a busbar; The bus cooling structure according to any one of claims 1 to 5 is disposed in the receiving cavity, one side of the insulating sheet is fixedly attached to the bus, and a heat dissipation channel is provided between the heat dissipation component and the housing.

7. The battery pack according to claim 6, characterized in that, In the height direction of the housing, the dimensions of the pole L1, the busbar L2, the insulating sheet L3, and the height of the heat dissipation assembly L4 satisfy the following order: L3>L4>L2>L1.

8. The battery pack according to claim 7, characterized in that, The height of the plurality of heat sinks is greater than the height of the busbar.

9. The battery pack according to claim 6, characterized in that, The housing is provided with a cooling plate, and the heat dissipation assembly is also provided with a contact part that contacts the cooling plate, and the contact part is connected to the connecting plate.

10. The battery pack according to claim 6, characterized in that, The cavity is also equipped with a fan facing the heat dissipation channel.

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