Battery pack

Abstract

The utility model provides a battery pack which comprises a shell and a battery module, an accommodating cavity is formed in the shell, the battery module is arranged in the accommodating cavity, the battery module comprises a plurality of battery monomers, a busbar and a protective piece, the plurality of battery monomers are sequentially arranged along the Y direction, and the protective piece is arranged in the accommodating cavity. Electrode terminals are arranged on the bottom surfaces of the single batteries along the Z direction, the electrode terminals of the two adjacent single batteries are connected through a busbar, and the protective part is connected with the single batteries and covers the busbar. Compared with the prior art, the heat exchange rate between the busbar and the outside world is delayed to a certain extent by arranging the protection part, the temperature change is more stable, and the problem of self condensation is reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to battery technology field especially relates to a battery pack. BACKGROUND

[0002] With the continuous maturity of technology, the application of power battery is more and more extensive, such as energy storage power supply system of water power, fire power, wind power and solar power station, or electric bicycle, electric motorcycle, electric vehicle and other electric vehicles, and part is also applied in military equipment and aerospace field. With the continuous expansion of the application field of power battery, the market demand is also increasing.

[0003] Because the heat released by the battery pack when working is considerable, the heat management component is needed to control the temperature of heat dissipation. However, in the case of large air humidity, cold and hot alternation and rapid temperature change, the heat management component will produce condensation on the surface with relatively low temperature, affecting its normal use.

[0004] Further, when the battery monomer is inverted and the bus bar is arranged below the battery pack, the condensation will flow to the bus bar at the low end under the influence of gravity, which has the safety risk of causing circuit short circuit or other serious problems. UTILITY MODEL CONTENT

[0005] To solve the above technical problems, the purpose of the utility model is to provide a battery pack, which is covered by a protection piece to reduce heat exchange between the bus bar and the outside world, avoid condensation and other phenomena caused by rapid temperature change of the bus bar, and the setting of the protection piece can also guide the condensation flow to avoid short circuit caused by flowing to the bus bar.

[0006] Based on this, the utility model provides a battery pack, the battery pack has X direction and Y direction, Z direction intersecting with each other, the battery includes:

[0007] The shell is internally formed with a containing cavity;

[0008] The battery module is arranged in the containing cavity, the battery module includes battery monomer, bus bar and protection piece, the battery monomer is provided with a plurality of, a plurality of battery monomers are sequentially arranged along the Y direction, the electrode terminal is arranged on the bottom surface of the battery monomer along the Z direction, the electrode terminals of two adjacent battery monomers are connected by the bus bar, and the protection piece is connected with the battery monomer and covers the bus bar.

[0009] In some embodiments of the application, the shell includes top cover, shell and bottom cover sequentially arranged and connected along the Z direction, the top cover, the shell and the bottom cover enclose to form the containing cavity, and the protection piece is located between the bus bar and the bottom cover.

[0010] In some embodiments of the present application, the battery pack further includes a heat exchanger, which is arranged along the Y direction and connected to the side surface of the battery cell along the X direction, and a heat conduction channel is provided in the heat exchanger.

[0011] In some embodiments of the present application, the protective member includes a connecting portion and an arch groove portion, the connecting portion is provided with multiple sections along the X direction, and two adjacent sections of the connecting portion are connected by the arch groove portion. The connecting portion and the bus are arranged along the Z direction, and the connecting portion is connected to the side of the bus close to the bottom cover, and the multiple sections of the connecting portion correspond to each of the buses respectively.

[0012] In some embodiments of the present application, the connecting portion is arranged along the XY plane, the arch groove portion is arranged in a U shape, the arch groove portion is opposite to the gap between two adjacent battery cells, and the arch groove portion and the heat exchange component are arranged along the Z direction.

[0013] In some embodiments of the present application, the arch groove portion is arranged to protrude toward the bottom surface of the battery cell along the Y direction.

[0014] In some embodiments of the present application, the arch groove portion is arranged to protrude away from the bottom surface of the battery cell along the Y direction.

[0015] In some embodiments of the present application, the protective member further includes a reinforcing portion, which is arranged along the X direction and connected to the connecting portion and / or the arch groove portion, and the reinforcing portion is connected to the bottom surface of at least one battery cell along the Z direction.

[0016] In some embodiments of the present application, an explosion-proof valve is provided on the battery cell, and the reinforcement portion shields the explosion-proof valve to isolate the explosion-proof valve from the bus bar.

[0017] In some embodiments of the present application, the battery pack satisfies at least one of the following conditions:

[0018] The distance between the connecting portion of the protective member and the bottom cover is d, and the range of d is 1 mm-20 mm;

[0019] The thickness of the connecting portion is denoted as h1, and the size of h1 is 0.05-5 mm;

[0020] The height of the arch groove is denoted as h2, and h2 is greater than 1.0 mm;

[0021] The thermal conductivity of the connecting portion is less than 1.0 W / (m·K);

[0022] The protective element has a fiber braided layer, the inner fiber angle of the fiber braided layer is denoted as α, and the range of α is 45°-90°;

[0023] The ceramicization temperature of the protective element is less than 500°C.

[0024] In some embodiments of the present application, the battery pack further includes a support member, which is arranged along the Z direction with the bottom cover and located above the bottom cover, one side of the support member is connected to the bottom cover, and the side of the support member facing away from the bottom cover abuts against the protective member.

[0025] In some embodiments of the present application, the support member is made of elastic foam material.

[0026] In some embodiments of the present application, the height of the support member is denoted as h3, and the size of h3 is 1-20 mm.

[0027] Compared with the prior art, the battery pack provided by the present invention has the following advantages:

[0028] This application inverts the battery to arrange the bus at the bottom of the battery. Different busbars can be connected to each other, which ensures the normal operation of the battery while also improving the thermal insulation effect, which is beneficial to maintaining the battery capacity; further, this application delays the heat exchange rate between the busbar and the outside world to a certain extent by setting a protective part, making its temperature change more stable and reducing the problem of condensation itself. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A schematic diagram of a battery explosion in this application;

[0030] Figure 2 A partial cross-sectional view of the battery of the present application along the Y direction;

[0031] Figure 3 for Figure 2 Detailed drawing of point A in the figure;

[0032] Figure 4 A partial cross-sectional view of the battery of the present application along the X direction;

[0033] Figure 5 for Figure 4 Detailed drawing of point B in the figure;

[0034] Figure 6 This is a schematic diagram of the battery module structure of this application;

[0035] Figure 7 This is a schematic cross-sectional view of the battery module of this application.

[0036] In the figure: 1, the shell; 11, the top cover; 12, the shell body; 13, the bottom cover; 14, the accommodating cavity; 2, the battery module; 21, the battery monomer; 211, the electrode terminal; 22, the heat exchange element; 221, the heat conduction flow channel; 23, the busbar; 24, the protective element; 241, the connecting part; 242, the arched groove part; 243, the reinforcing part; 3, the support element. DETAILED DESCRIPTION

[0037] The specific embodiments of the present application will be further described in detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate the present application, but not to limit the scope of the present application.

[0038] It should be understood that the terms "front", "back" and the like are used in this application to describe various information, but these information should not be limited to these terms, and these terms are only used to distinguish the same type of information from each other. For example, the "front" information can also be referred to as "back" information, and the "back" information can also be referred to as "front" information without departing from the scope of the present application. In the embodiments of the present application, the side of the vacuum packaging bag facing the operator is defined as the front side.

[0039] The term "parallel" in this application not only includes the case of absolute parallel, but also includes the case of approximate parallel which is generally recognized in engineering, such as "parallel" refers to the angle formed by a straight line and a straight line, a straight line and a surface, or a surface and a surface is-1°~1° state; at the same time, "perpendicular" also not only includes the case of absolute perpendicular, but also includes the case of approximate perpendicular which is generally recognized in engineering, such as "perpendicular" refers to the angle formed by a straight line and a straight line, a straight line and a surface, or a surface and a surface is 89°~91° state. The distance is equal or the angle is equal, not only includes the case of absolute equality, but also includes the case of approximate equality which is generally recognized in engineering, that is, there can be a certain error, such as the state of tolerance range is-1%~1%.

[0040] Further, as shown in Figures 1 to 7 It is defined that the battery pack of the present application has X direction, Y direction and Z direction intersecting with each other.

[0041] As shown in Figures 1 to 7 The present application provides a kind of battery pack, it includes shell 1 and battery module 2, wherein the inside of shell 1 is formed with accommodating cavity 14, battery module 2 is located in accommodating cavity 14, battery module 2 includes battery monomer 21, busbar 23 and protective element 24, battery monomer 21 is equipped with multiple, multiple battery monomer 21 is sequentially arranged along Y direction, electrode terminal 211 is provided on the bottom surface of battery monomer 21 along Z direction, electrode terminal 211 between adjacent two battery monomer 21 is connected by busbar 23, protective element 24 is connected with battery monomer 21 and covers busbar 23.

[0042] Based on the above structure, when in use, the battery monomer 21 is inverted and the busbars 23 are arranged at the bottom of the battery monomer 21, the different busbars 23 can be connected, which ensures the normal operation of the battery monomer 21 and improves the heat preservation effect, which is beneficial to the maintenance of the battery capacity; further, the application covers the busbars 23 with the protective piece 24, which greatly reduces the heat exchange between the busbars 23 and the outside world, the temperature of the busbars 23 is more stable, the problem of condensation is solved, the risk of short circuit is also reduced, and the safety of the battery is improved; in addition, the arrangement of the busbars 23 and the protective piece 24 improves the heat spread problem after the inverted battery thermal runaway, and further improves the safety of the battery pack.

[0043] Optionally, in some embodiments of the application, the shell 1 includes a top cover 11, a shell 12 and a bottom cover 13 arranged in sequence along the Z direction and connected with each other, the top cover 11, the shell 12 and the bottom cover 13 form a containing cavity 14, and the protective piece 24 is located between the busbars 23 and the bottom cover 13. Based on the above structure, the shell 1 of the application is spliced by the top cover 11, the shell 12 and the bottom cover 13, and the overall structure is smoother and easier to assemble.

[0044] Further, in some embodiments of the application, the battery pack further comprises a heat exchange piece 22, which is arranged along the Y direction and connected with the side surface of the battery monomer 21 along the X direction, and the heat exchange piece 22 is provided with a heat conduction flow channel 221, and the heat conduction flow channel 221 is filled with a heat conduction fluid capable of exchanging heat with the battery monomer 21. In this way, the arrangement of the heat exchange piece 22 provides a thermal management component for the battery monomer 21, and the operator fills the heat conduction fluid into the heat conduction flow channel 221 to make the heat exchange piece 22 exchange heat with the battery monomer 21, thereby realizing the cooling treatment of the battery monomer 21.

[0045] Optionally, for the protective piece 24 of the application, it includes a connecting part 241 and an arch groove part 242, wherein the connecting part 241 is provided with multiple sections along the X direction, the adjacent two connecting parts 241 are connected through the arch groove part 242, the connecting part 241 is arranged along the Z direction with the busbar 23, and the connecting part 241 is connected to one side of the busbar 23 close to the bottom cover 13, and the multiple connecting parts 241 correspond to the respective busbars 23. Based on the above structure, the arrangement of the protective piece 24 can shield the adjacent busbars 23 to play a heat preservation role for the busbars 23, so that the temperature change speed of the battery module 2 is reduced, thereby reducing the speed and probability of condensation, and water vapor can be blocked from contacting the busbars 23 to avoid the influence of condensation of dew on the busbars 23.

[0046] Furthermore, in some embodiments of the present application, the connection portion 241 of the protective member 24 is arranged along the XY plane, and accordingly, the arched groove portion 242 connecting the connection portion 241 is arranged in a U-shape. Specifically, the arched groove portion 242 is opposite to the gap between two adjacent battery cells 21 and is arranged along the Z direction together with the heat exchange member 22. It can be understood that the arched groove portion 242 at least partially covers the gap between two adjacent battery cells 21 along the Z direction.

[0047] like Figure 2 and Figure 3 As shown, the battery cell 21 has a bottom surface extending along the Y direction, with an arched groove 242 protruding toward the bottom surface. Thus, the arched groove 242 protruding toward one side of the bottom of the battery cell 21 can prevent condensation from flowing along the adjacent connection portion 241, thereby preventing condensation from flowing along the arched groove 242 to other connection portions, thereby blocking the flow of condensation between different busbars 23 and preventing short circuits.

[0048] Furthermore, based on Figure 2 、 Figure 3 Regarding the arrangement of the middle arch groove 242, in some other embodiments of the present application, the arch groove 242 may also be configured to protrude away from the bottom of the battery cell 21. In this case, the arch groove 242 forms a water collection trough, and condensation water flowing along the connecting portion 241 can be collected by the arch groove 242 when it reaches the arch groove 242, thereby preventing the condensation water from flowing to other areas. Of course, when designing in this manner, the depth of the arch groove 242 should be considered to prevent condensation water in the arch groove 242 from flowing out due to the arch groove 242 being too shallow.

[0049] Optional, such as Figure 4 and Figure 5 As shown, the protective member 24 of the present application also includes a reinforcement portion 243, which is arranged along the X direction and is connected to both the connection portion 241 and the arch groove portion 242. Of course, the reinforcement portion 433 may also be connected only to the connection portion 241 or the arch groove portion 242. Furthermore, the reinforcement portion 243 is connected to the bottom surface of at least one battery cell 21 along the Z direction. For the battery cells of the present application, the gas-liquid-solid mixture ejected during thermal runaway is very likely to cause secondary hazards, of which the secondary hazards caused to the electrical parts are the most serious, resulting in hazards such as arcing (breaking through metal plates, melting metal plates, etc.), short circuits, insulation failure, etc. In this case, thermal runaway will be aggravated, difficult to control, and more likely to cause heat spread. The reinforcement portion 243 of the protective member 24 is provided to protect against the ejecta, reduce the impact of thermal runaway on the bus 23, and avoid situations such as short circuits caused by the ejecta connecting different conductors (such as adjacent busbars 23 or busbars and other charged bodies). It can effectively limit the thermal runaway process and avoid chain reactions caused by heat spread.

[0050] Furthermore, the battery cell 21 of the present application is provided with an explosion-proof valve. The reinforced portion 243 of the protective member 24 is positioned around the explosion-proof valve to shield the valve, thereby isolating the valve from the bus 23. Based on the above structure, the protective member 24 isolates the electrical connection area where the bus 23 is located from the explosion-proof valve, providing high-temperature protection and preventing the bus from being directly impacted by the high-temperature, high-pressure fluid released by the runaway battery cell. This prevents the high-temperature, high-pressure fluid from directly impacting the bus 23 when the battery cell erupts.

[0051] Furthermore, for the protective member 24 of the present application, the distance between the connecting portion 241 of the protective member 24 and the bottom cover 13 is d, and the range of d is 1mm-20mm. For the connecting portion 241 of the present application, the concave height is too small, the effect of blocking water droplets is not good, and it is difficult to play the role of drainage. Therefore, the height of the concave is increased as much as possible to enhance the water blocking effect. However, since the battery cell 21 is arranged in the shell 1, the size of the accommodating cavity 14 of the shell 1 is limited. If the connecting portion 241 is arranged too close to the bottom cover 13, the protective member will occupy a large space, which will in turn reduce the volume utilization of the battery. Therefore, the maximum height of the connecting portion 241 is limited by the height of the bottom protection.

[0052] Optionally, the thickness of the connection portion 241 is denoted as h1, and the size of h1 is 0.05-5 mm. The thickness of the connection portion cannot be too small, otherwise the thermal insulation performance cannot be guaranteed and it is difficult to resist the impact of the high-temperature and high-pressure fluid released by the runaway battery cell 1. At the same time, the thickness of the connection portion cannot be too large. If the connection portion 241 is too thick, it will easily occupy the space of the accommodating cavity 14, resulting in reduced space utilization.

[0053] Furthermore, the thermal conductivity of the connecting portion 241 is less than 1.0 W / (m·K). The lower the thermal conductivity, the better the insulation effect, and the correspondingly thinner the thickness of the connecting portion 241. The thickness of the connecting portion 241 should not be too large, otherwise it will increase the weight and be detrimental to the lightweight design.

[0054] Furthermore, the height of the arched groove 242 is denoted as h2, and h2 is greater than 1.0 mm. The arched groove 242 needs to have a certain height to collect condensed water or to drain the condensed water to prevent condensed water from accumulating on the busbar 23. Of course, due to the limited overall height of the accommodating chamber 14, an excessive height of the arched groove 242 will also reduce the volume utilization of the battery. Therefore, the maximum height of the arched groove 242 is limited by the height of the bottom guard.

[0055] Optionally, in some embodiments of the present application, the protective member 24 includes a fiber braided layer, where the inner fiber angle of the fiber braided layer is denoted as α, and the range of α is 45°-90°. The provision of the fiber braided layer can improve the protective member 24's resistance to temperature and pressure shocks, thereby ensuring the structural strength of the protective member 24.

[0056] Furthermore, the ceramicization temperature of the protective member 24 is less than 500° C. The lower the ceramicization temperature, the lower the high temperature resistance of the protective member 24 and the higher its safety.

[0057] Optionally, in some embodiments of the present application, the battery pack further includes a support member 3, which is arranged along the Z direction with the bottom cover 13 and is located above the bottom cover 13. One side of the support member 3 is connected to the bottom cover 13, and the side of the support member 3 facing away from the bottom cover 13 abuts against the protective member 24. The provision of the support member 3 can assist and support the provision of the protective member 24, thereby reducing the difficulty of connecting the protective member 24 to the bus bar 23 or the battery cell 21.

[0058] Furthermore, in some embodiments of the present application, the support member 3 is made of an elastic foam material. The height of the support member 3 is denoted as h3, and the size of h3 ranges from 1 to 20 mm. The size of the support member 3 also affects the battery pack. If the support member is too small, it cannot provide reliable support for the protective member 24. If the support member 3 is too large, the volume utilization of the battery pack will be reduced. Therefore, the height of the support member 3 needs to be limited.

[0059] To sum up, the present invention provides a battery pack, which includes a shell 1 and a battery module 2, wherein a accommodating cavity 14 is formed inside the shell 1, and the battery module 2 is arranged in the accommodating cavity 14. The battery module 2 includes a battery cell 21, a bus 23 and a protective member 24. There are multiple battery cells 21, and the multiple battery cells 21 are arranged in sequence along the Y direction. The electrode terminals 211 are provided on the bottom surface of the battery cell 21 along the Z direction. The electrode terminals 211 of two adjacent battery cells 21 are connected by a bus 23. The protective member 24 is connected to the battery cell 21 and covers the bus 23. Compared with the prior art, the present application inverts the battery to arrange the bus at the bottom of the battery, and different busbars can be connected to each other, which ensures the normal operation of the battery while also improving the thermal insulation effect, which is beneficial to maintaining the battery capacity; the setting of the protective part slows down the heat exchange rate between the busbar and the outside world to a certain extent, making its temperature change more stable and reducing its own condensation problem; the protective part has an arch groove to collect and drain condensation, avoiding short circuits between adjacent busbars due to condensation of water dew; the protective part can also limit the thermal runaway process to avoid chain reactions caused by heat spread.

[0060] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and replacements can be made without departing from the technical principles of the present invention. These improvements and replacements should also be regarded as the scope of protection of the present invention.

Claims

1. A battery pack, characterized in that: The battery pack has an X direction, a Y direction, and a Z direction intersecting in pairs, and the battery pack includes: A housing (1), wherein a receiving cavity (14) is formed inside the housing (1); A battery module (2) is provided in the accommodating cavity (14). The battery module (2) comprises a battery cell (21), a busbar (23) and a protective member (24). A plurality of battery cells (21) are provided, and the plurality of battery cells (21) are sequentially arranged along the Y direction. Electrode terminals (211) are provided on the bottom surface of the battery cell (21) along the Z direction. The electrode terminals (211) of two adjacent battery cells (21) are connected via the busbar (23). The protective member (24) is connected to the battery cell (21) and covers the busbar (23).

2. The battery pack according to claim 1, wherein: The housing (1) comprises a top cover (11), a shell (12) and a bottom cover (13) which are sequentially arranged and interconnected along the Z direction; the top cover (11), the shell (12) and the bottom cover (13) enclose the accommodating cavity (14); and the protective member (24) is located between the busbar (23) and the bottom cover (13).

3. The battery pack according to claim 2, wherein: The battery pack further comprises a heat exchange component (22), the heat exchange component (22) being arranged along the Y direction and connected to the side surface of the battery cell (21) along the X direction, and a heat conduction channel (221) being provided in the heat exchange component (22).

4. The battery pack according to claim 3, wherein: The protective member (24) includes a connecting portion (241) and an arch groove portion (242); the connecting portion (241) is provided with multiple sections along the X direction; two adjacent sections of the connecting portion (241) are connected via the arch groove portion (242); the connecting portion (241) and the busbar (23) are provided along the Z direction; the connecting portion (241) is connected to a side of the busbar (23) close to the bottom cover (13); and the multiple sections of the connecting portion (241) correspond to each of the busbars (23).

5. The battery pack according to claim 4, characterized in that: The connecting portion (241) is arranged along the XY plane, the arch groove portion (242) is arranged in a U shape, the arch groove portion (242) is opposite to the gap formed by two adjacent battery cells (21), and the arch groove portion (242) and the heat exchange component (22) are arranged along the Z direction.

6. The battery pack according to claim 5, characterized in that: The battery cell (21) has a bottom surface arranged along the Y direction, and the arch groove portion (242) is arranged to protrude toward the bottom surface; or the arch groove portion (242) is arranged to protrude in a direction away from the bottom surface.

7. The battery pack according to claim 4, characterized in that: The protective member (24) further includes a reinforcing portion (243), the reinforcing portion (243) being arranged along the X direction and connected to the connecting portion (241) and / or the arch groove portion (242), and the reinforcing portion (243) being connected to the bottom surface of at least one battery cell (21) along the Z direction.

8. The battery pack according to claim 7, characterized in that: An explosion-proof valve is provided on the battery cell (21), and the reinforcement portion (243) shields the explosion-proof valve to isolate the explosion-proof valve from the busbar (23).

9. The battery pack according to claim 4, characterized in that: The battery pack meets at least one of the following conditions: The distance between the connecting portion (241) of the protective member (24) and the bottom cover (13) is d, and the range of d is 1 mm-20 mm; The thickness of the connecting portion (241) is denoted as h1, and the size of h1 is 0.05-5 mm; The height of the arch groove portion (242) is denoted as h2, and h2 is greater than 1.0 mm; The thermal conductivity of the connecting portion (241) is less than 1.0 W / (m·K); The protective member (24) has a fiber braided layer, the inner fiber angle of the fiber braided layer is denoted as α, and the range of α is 45°-90°; The ceramicization temperature of the protective element (24) is less than 500°C.

10. The battery pack according to claim 1, wherein: The battery pack further comprises a support member (3), wherein the support member (3) and the bottom cover (13) are arranged along the Z direction and are located above the bottom cover, one side of the support member (3) is connected to the bottom cover (13), and the side of the support member (3) facing away from the bottom cover (13) abuts against the protective member (24).

11. The battery pack according to claim 10, characterized in that: The support member (3) is made of elastic foam material, and / or the height of the support member (3) is denoted as h3, and the size of h3 is 1-20 mm.

Images