Battery box, battery pack and electric device

Abstract

A battery box comprises a box body with an opening in the top, the box body comprises a shell component and a lining component, the lining component is of a bent structure to form a first groove cavity with a downward opening and a second groove cavity with an upward opening, the first groove cavity comprises a first liquid flow channel, the second groove cavity comprises a battery containing groove, and the shell component comprises a shell bottom component. The two ends or the middle of the shell bottom component in the y direction comprise first concave parts and / or second concave parts, openings of the first concave parts and / or the second concave parts intersect with openings of the first groove cavities respectively, a space defined by the inner walls of the first concave parts and the bottom wall of the lining component comprises a first confluence channel, and a space defined by the inner walls of the second concave parts and the bottom wall of the lining component comprises a second confluence channel. Each first groove cavity is respectively communicated with the first concave part and the second concave part at the intersection through the openings, so that each first liquid flow channel is respectively communicated with the first confluence channel and the second confluence channel to form a cooling liquid circulation channel, and the battery box structure can retard thermal runaway spreading and diffusion of the battery.

Description

TECHNICAL FIELD

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

[0002] With the rapid popularization of electric vehicles, the scale of the number of electric vehicles is increasingly large, and the large power fast charging technology is gradually popularized. The heat dissipation requirement of the corresponding battery is higher and higher. The existing vehicle-mounted battery often has thermal runaway. If the thermal runaway cannot be blocked in time after the accidental thermal runaway, it may spread to the remaining battery monomers in the battery pack, which may ignite and burn the vehicle. On the other hand, although the protection level of the vehicle-mounted battery pack is not lower than IP67, the electrical insulation of the existing vehicle-mounted battery is often lost due to accidental water seepage in the battery pack, thereby causing vehicle failure. SUMMARY

[0003] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, in a first aspect, the present application provides a battery box which can realize more balanced heat dissipation for all battery monomers in the box compared with the prior art. Even if the battery monomer accidentally has thermal runaway, the battery box is beneficial to block the spread of thermal runaway in time. In addition, the battery box can reduce the water seepage failure in the box or reduce the loss caused by water seepage.

[0004] In a second aspect, the present application also provides a battery pack, which has the battery box.

[0005] In a third aspect, the present application also provides an electric vehicle, which has the battery pack.

[0006] In a fourth aspect, the present application also provides a circuit module heat dissipation box, which has the corresponding structural features of the battery box.

[0007] In a first aspect, a battery box includes a top-opened box body, the box body can accommodate a plurality of battery monomers, the box body includes an outer shell member and an inner liner member, the inner liner member is arranged in a bent structure to form a first slot cavity with an opening downward, and a second slot cavity adjacent thereto and with an opening upward, the inner liner member includes a plurality of first slot cavities and second slot cavities arranged along an x direction, the cross sections of the slot cavities extend along a y direction, and the first slot cavities and the second slot cavities are parallel and alternately arranged, the first slot cavities include first liquid flow channels, the second slot cavities include battery accommodating grooves, and at least one maximum surface of the accommodated battery monomers is in thermal conductive connection with the wall of the first liquid flow channel.

[0008] The shell member includes a shell bottom member, the inner wall of the shell bottom member is assembled with the bottom wall of the inner liner member, the shell bottom member includes a first recess and / or a second recess at the two ends or the middle part along the y direction, the first recess and the second recess are upwardly open, the openings of the first recess and the second recess respectively intersect with the openings of each of the first groove cavities, the space enclosed by the inner wall of the first recess and the bottom wall of the inner liner member includes a first flow channel, the space enclosed by the inner wall of the second recess and the bottom wall of the inner liner member includes a second flow channel, each of the first groove cavities and the first recess and the second recess are respectively communicated with each other through the openings at the intersection, so that each of the first flow channels and the first flow channel and the second flow channel are respectively communicated to form a cooling liquid circulation channel.

[0009] The outer wall of the shell member includes an inlet and an outlet, the inlet is communicated with the first flow channel, and the outlet is communicated with the second flow channel.

[0010] The two ends of the first groove cavity are sealed and fixedly sealed, and the periphery of the inner liner member is sealingly and fixedly engaged with the shell member.

[0011] In one possible implementation, the specific structural mode of the cooling liquid circulation channel of the battery box includes any one of the following possible implementations.

[0012] In one possible implementation a, the shell bottom member includes the first recess and the second recess at the two ends along the y direction respectively, and the inlet and the outlet are respectively arranged on the same side of the shell member along the x direction.

[0013] In one possible implementation b, the shell bottom member includes the first recess and the second recess at the two ends along the y direction respectively, and the inlet and the outlet are respectively arranged on the opposite sides of the shell member along the x direction.

[0014] In one possible implementation c, the shell member includes a first end and a second end along the y direction, the first end of the shell bottom member includes the first recess and the second recess arranged side by side along the x direction, the inlet and the outlet are respectively arranged on the opposite sides of the shell member along the x direction, and the second end includes a third recess, the third recess is upwardly open, the opening of the third recess intersects with the opening of each of the first groove cavities, the space enclosed by the inner wall of the third recess and the bottom wall of the inner liner member includes a third flow channel, and the third flow channel and the first flow channel are communicated with each other through the openings at the intersection.

[0015] In one possible implementation d, the shell bottom member includes the first recess at the middle part along the y direction and the second recess at the two ends respectively, and the inlet and the outlet are respectively arranged on the same side or the opposite side of the shell member along the x direction.

[0016] In a possible implementation e, the shell bottom member includes a first recess in the middle along the y direction, each side of the first recess along the y direction includes a second recess, and a separation structure is included between the recesses. At each half-height position of the first groove cavity, a longitudinal separation member is included in the front section and the rear section, respectively, and a vertical separation member is included corresponding to the separation structure. The first groove cavity is divided into two first liquid flow channels in the upper and lower positions by the longitudinal separation member and the vertical separation member, and is connected to the first and second flow channels, respectively, so that the cooling liquid in the first groove cavity flows in opposite directions. The liquid inlet and the liquid outlet are arranged on the same side or on different sides of the shell member along the x direction.

[0017] In a possible implementation f, the first end of the shell bottom member includes the first recess and the second recess arranged in parallel along the x direction, a separation structure is included between the recesses, a longitudinal separation member is included at each half-height position of the first groove cavity, and a vertical separation member is included corresponding to the separation structure. The first groove cavity is divided into two first liquid flow channels in the upper and lower positions by the longitudinal separation member and the vertical separation member, and is connected to the first and second flow channels, respectively, so that the cooling liquid in the first groove cavity flows in opposite directions. The liquid inlet and the liquid outlet are arranged on the same side or on different sides of the shell member along the x direction.

[0018] In a possible implementation g, the first end of the shell bottom member includes the first recess and the second recess arranged in parallel along the x direction, the second end includes the third recess, the first recess and the second recess include flow guides at the intersection with the opening of the first groove cavity, the flow guides are connected or blocked to the cooling liquid flow channel at the intersection by selecting flow guide holes, and the first groove cavity is connected to the first recess and the second recess in sequence and staggered, so that the cooling liquid of adjacent first groove cavities flows in opposite directions. The liquid inlet and the liquid outlet are arranged on the same side or on different sides of the shell member along the x direction.

[0019] In a possible implementation h, the shell bottom member includes a first recess in the middle along the y direction, each side of the first recess along the y direction includes a second recess or only one side includes a second recess, and each end along the y direction includes a third recess. The first recess and the second recess include flow guides at the intersection with the opening of the first groove cavity, the flow guides are connected or blocked to the cooling liquid flow channel at the intersection by selecting flow guide holes, and the first groove cavity is connected to the first recess and the second recess in sequence and staggered, so that the cooling liquid of adjacent first groove cavities flows in opposite directions. The liquid inlet and the liquid outlet are arranged on the same side or on different sides of the shell member along the x direction.

[0020] In a possible implementation, the first end of the shell bottom member includes the first recess and the second recess arranged in parallel along the x direction, and the second end includes the first recess and the second recess arranged in parallel along the x direction. The first recess and the second recess include flow guide members at intersections with the first groove opening. The flow guide members are provided with flow guide holes to communicate or block the flow channel of the cooling liquid at the intersections. The first grooves are staggered and sequentially connected to the first recess and the second recess at the same end, so that the cooling liquid of adjacent first grooves flows in opposite directions. The liquid inlet and the liquid outlet are arranged on the same side or different sides of the shell member along the x direction.

[0021] In a possible implementation, the shell bottom member includes a third recess. The third recess is upwardly open and parallel to the first grooves along the y direction and opposite to the first groove opening. The third recess extends to the bottom of the second groove along the x direction. The inner wall of the third recess and the bottom wall of the second groove form a space, which includes a second flow channel. The second flow channel and the first flow channel are connected to each other through the third recess opening and the first groove opening. The upper wall of the second groove bottom plate is in thermal conductive connection with the bottom surface of the battery cell.

[0022] In a possible implementation, the first groove has a T-shaped groove structure in the cross section along the y direction. The two side walls of the top of the T-shaped groove structure cover at least part of the top surface of the battery cell and are in thermal conductive connection with the top surface.

[0023] In a possible implementation, the first groove includes a first side plate and a second side plate. The first side plate and the second side plate are arranged at intervals along the x direction. The first side plate and / or the second side plate include a plurality of fourth recesses. The fourth recesses are open toward the second groove. The fourth recesses are arranged at right angles along the length direction. Alternatively, the fourth recesses are arranged at oblique angles along the length direction. Alternatively, the fourth recesses are arranged as a plurality of circular or elliptical recesses. The recesses are open toward the second groove and are arranged at intervals on the first side plate and / or the second side plate.

[0024] In a second aspect, a battery pack includes a plurality of battery cells. The battery cells are provided with heat insulation films between the end surfaces. The battery pack includes any one of the battery boxes. The battery pack includes one or more box bodies. The plurality of box bodies are arranged along the x direction and / or along the y direction, or are stacked along the z direction.

[0025] In a possible implementation, the battery cells in the same row are provided with electrical connectors on the top of the battery cells. The top surface of the electrical connector is in electrically insulated and thermally conductive connection with the wing wall of the top of the T-shaped groove structure of the first groove.

[0026] In one possible implementation, the multiple liquid outlet branches of the battery pack are respectively connected in series with solenoid valves, or the multiple liquid inlet branches are respectively connected in series with solenoid valves.

[0027] In a third aspect, an electric vehicle includes an on-board liquid cooling system, and the electric vehicle includes any of the battery packs described above, the battery pack includes a box cover, an inner wall of the box cover is covered with a thermal insulation material, the battery pack is arranged at a bottom of the electric vehicle, a liquid inlet and a liquid outlet of the battery pack are respectively connected to the on-board liquid cooling system through pipelines, and the battery pack provides driving electric energy for the electric vehicle.

[0028] In a fourth aspect, a circuit module heat dissipation box includes a box body with an open top, the box body includes an outer shell member and an inner lining member, the inner lining member is arranged in a bent structure to form a first slot cavity with an opening downward and a second slot cavity adjacent to the first slot cavity and with an opening upward, the inner lining member includes a plurality of the first slot cavities and the second slot cavities arranged in parallel and alternately along a y direction, the first slot cavities include first liquid flow channels, the second slot cavities accommodate circuit modules and electrically insulated and thermally conductive liquid, the circuit modules are at least partially immersed in the electrically insulated and thermally conductive liquid, the circuit modules are in thermal conductive connection with walls of the first liquid flow channels through the electrically insulated and thermally conductive liquid, the electrically insulated and thermally conductive liquid in each of the second slot cavities is isolated from each other and does not flow, side plates of the first slot cavities are flat or have a special-shaped plate structure, the special-shaped plate structure includes a plurality of fourth grooves, the fourth grooves have openings facing the second slot cavities, and the fourth grooves are arranged in parallel or at an angle.

[0029] The outer shell member includes a shell bottom member, an inner wall of the shell bottom member is assembled with a bottom wall of the inner lining member, the shell bottom member includes a first recess and / or a second recess at both ends or in a middle portion, the first recess and the second recess have openings facing upward, the openings of the first recess and the second recess respectively intersect with openings of each of the first slot cavities, a space formed by the inner wall of the first recess and the bottom wall of the inner lining member includes a first flow convergence channel, a space formed by the inner wall of the second recess and the bottom wall of the inner lining member includes a second flow convergence channel, each of the first slot cavities and the first recess and the second recess are respectively connected to each other through the openings at the intersection, so that each of the first liquid flow channels and the first flow convergence channel and the second flow convergence channel are respectively connected to form a cooling liquid circulation channel.

[0030] Outer walls of the outer shell member include a liquid inlet and a liquid outlet, the liquid inlet and the liquid outlet are respectively connected to the first flow convergence channel and the second flow convergence channel, both ends of the first slot cavities are sealed and fixed, and a periphery of the inner lining member is sealingly and fixedly connected to the outer shell member.

[0031] The battery box of the present application can realize more balanced heat dissipation for all battery monomers in the box, and even if the battery monomers accidentally heat out of control, the battery box is beneficial to timely block the spread and diffusion of heat out of control; in addition, the battery box can reduce the water seepage failure in the box or reduce the loss caused by water seepage. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 .Embodiment battery box a schematic diagram;

[0033] Figure 2 .Embodiment battery box cooling liquid circulating channel a schematic diagram; Figure 2 .A.Embodiment first recess bottom surface partial sectional view;

[0034] Figure 3 .a.Embodiment lining member a schematic diagram;

[0035] Figure 4 ..a.Embodiment shell member a schematic diagram;

[0036] Figure 5 .a.Embodiment a cooling liquid flow path a schematic diagram;

[0037] Figure 6 .b.Embodiment b cooling liquid flow path a schematic diagram;

[0038] Figure 7 .c.Embodiment c shell member a schematic diagram;

[0039] Figure 8 .c.Embodiment c cooling liquid flow path a schematic diagram;

[0040] Figure 9 .d.Embodiment d shell member a schematic diagram;

[0041] Figure 10 .d.Embodiment d cooling liquid flow path a schematic diagram;

[0042] Figure 11 .e.Embodiment e lining member a schematic diagram;

[0043] Figure 12 .e.Embodiment e shell member a schematic diagram;

[0044] Figure 13 .e.Embodiment e cooling liquid flow path a schematic diagram;

[0045] Figure 14 .f.Embodiment f lining member a schematic diagram;

[0046] Figure 15 .f.Embodiment f shell member a schematic diagram;

[0047] Figure 16 .f. Example f - Cooling fluid flow path - schematic view

[0048] Figure 17 .m. Example m - First deflector - schematic view Figure 17 .n. Example n - Second deflector - schematic view

[0049] Figure 17 g. Example g - Housing member - schematic view

[0050] Figure 18 .g. Example g - Cooling fluid flow path - schematic view

[0051] Figure 19 .h. Example h - Housing member - schematic view

[0052] Figure 20 .h. Example h - Cooling fluid flow path - schematic view

[0053] Figure 21 .i. Example i - Housing member - schematic view

[0054] Figure 22 .i. Example i - Cooling fluid flow path - schematic view

[0055] Figure 23 . Example - Housing member - schematic view showing direct communication between the recesses at the ends and the third groove

[0056] Figure 24 . Example - Inner liner member - schematic view showing the first slot cavity having a T-shaped slot structure

[0057] Figure 25 . Example - Inner liner member - schematic view showing the fourth groove having an oblique angle arrangement

[0058] Figure 26 .a. Example - Circuit module - schematic view Figure 26 .b. Example - Circuit module - schematic view showing the heat sink

[0059] Reference signs:

[0060] 1 - inner lining member; 11 - first groove cavity; 12 - second groove cavity; 111 - wing wall; 112 - elastic gel; 114 - fourth groove; 101 - longitudinal separation member; 102 - vertical separation member; 1020 - recess opening intersecting with first groove cavity opening; 2 - outer shell member; 20 - shell bottom member; 21 - first recess; 22 - second recess; 23 - third recess; 24 - liquid inlet; 25 - liquid outlet; 213 - third groove; 201 - isolation structure; 210 - first flow guide plate; 220 - second flow guide plate; 211 - first flow guide hole; 222 - second flow guide hole; 3 - battery monomer; 4 - circuit module. DETAILED DESCRIPTION

[0061] The following is described in detail through a plurality of embodiments, and the technical features and corresponding beneficial effects of the present application compared with the prior art are shown;

[0062] It should be noted that "one embodiment" or "an embodiment" described in the specification means that the specific features, structures or characteristics described in connection with the embodiment are included in one or more embodiments of the present application. Therefore, the statements "in one embodiment", "in an embodiment" appearing in different places in the specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized. The terms "include", "contain", "have" and their variants mean "include but not limited to", unless otherwise specifically emphasized. A and / or B means A, B, A+B three ways.

[0063] The dimensions and proportions in the drawings of the present specification are not the actual dimensions or proportions of the products implemented in the drawings;

[0064] In this specification, 1. The calculation of the cooling liquid flow value is an approximate value, ignoring the temperature rise caused by the error; 2. The battery monomer includes the square shell battery, the soft package battery, and the square shell battery includes the blade battery; the battery type includes the lithium battery; 3. The cooling liquid includes cooling water, ethylene glycol solution, or propylene glycol solution; 4. The cooling liquid circulation channel refers to the cooling liquid circulation flow path and the liquid flow cavity, which is connected to the liquid cooling system through the inlet and outlet liquid pipe interfaces to realize the circulation of the cooling liquid; 5. The resistance refers to the block or delay; 6. The heat conduction connection includes contact fitting connection, or indirect connection through heat conduction glue, heat conduction pad or heat conduction liquid; 7. The x direction, y direction, z direction, two by two perpendicular to each other; up, down, top, bottom, height, vertical refers to the z direction; two ends, same end, first end, second end, end, front and back, longitudinal, length, one row, two rows, multiple rows refer to the y direction; flat row, flat angle, inclined angle refers to relative to the y direction; width, thickness, left and right, refers to the x direction, side plate, side, side wall perpendicular to the x direction; 8. The isolation structure refers to the structure on the shell bottom member which blocks the cooling liquid flow between the first and adjacent second flow channels. 9. Electrically insulated heat conducting liquid includes hydrocarbon-based cooling liquid, fluorocarbon-based cooling liquid, and organic silicon-based cooling liquid; 10. The superposition assembly includes the contact and / or fixed connection of the combined surface; 11. The optional refers to the optional setting; 12. The first half near the first end, the second half near the second end.

[0065] In an embodiment of the battery box usage scenario, the battery pack containing the battery box is installed at the bottom of the vehicle. The inventor has found in related research and development practice that the shell bottom plate of the battery box is often damaged due to scratching during vehicle driving, and the driver fails to perceive and repair in time, resulting in water ingress into the box to cause battery insulation failure when driving in the rain after the bottom plate of the battery box is damaged; in addition, investigation has found that the cooling liquid pipe interface in the box will be deformed or the sealing ring will be aged due to vibration stress during vehicle use, causing cooling water leakage, and water accumulation in the box causes battery insulation failure; on the other hand, in order to shorten the charging time of the vehicle, high-power charging is gradually popularized, and the vehicle-mounted battery is more efficient in heat dissipation to avoid excessive local temperature rise of the battery during charging to trigger thermal runaway; in addition, the inventor has learned from research and development practice that it is difficult to trigger thermal runaway immediately when the temperature is not higher than 120℃, and related tests have shown that the temperature threshold for triggering thermal runaway of lithium battery is not less than 120℃.

[0066] In an embodiment, (refer to Figure 1 , Figure 2 , Figure 2 A, Figure 3 .a, Figure 4 .a, Figure 5a), a battery box, comprising a top opening box body, the size of which is adapted to the actual use scene, the box body comprising an outer shell member 2 and an inner liner member 1, the inner liner member 1 being arranged in a bending structure, comprising a plurality of bending structures arranged in the x direction by a single layer of sheet material, the sheet material being a thin-walled material capable of water and heat conduction, including stainless steel sheet, aluminum alloy sheet, copper sheet, and composite sheet material coated with an electrically insulating layer on the surface; the aforementioned bending structure forms a first groove cavity 11 with the opening downward, and a second groove cavity 12 adjacent to it with the opening upward, the plurality of first groove cavities 11 and the plurality of second groove cavities 12 are parallel to each other, arranged alternately in the x direction, the cross section of the groove cavity extends in the y direction, the first groove cavity 11 comprises a first liquid flow channel, and the second groove cavity 12 comprises a battery containing groove which contains one or two rows of battery monomers 3, and at least one maximum surface of the contained battery monomer 3 is in heat conduction connection with the wall of the first liquid flow channel, the battery monomer 3 is stationary in the second groove cavity 12, and the width and height of the second groove cavity 12 are adapted to the size of the contained battery monomer 3.

[0067] The outer shell member 2 comprises a shell bottom member 20, the inner wall of the shell bottom member 20 is assembled with the bottom wall of the inner liner member 1, and the shell bottom member 20 comprises a first recess 21 and / or a second recess 22 at both ends or in the middle along the y direction; the first recess 21 and the second recess 22 are upwardly open, the openings of the first recess 21 and the second recess 22 respectively intersect with the opening of each first groove cavity 11, and are respectively connected to each other through the respective openings at the intersection 1020, the space enclosed by the inner wall of the first recess 21 and the bottom wall of the inner liner member 1 comprises a first flow channel, and the space enclosed by the inner wall of the second recess 22 and the bottom wall of the inner liner member 1 comprises a second flow channel, each first groove cavity 11 is respectively connected to the first recess 21 and the second recess 22 through the opening at the intersection 1020, so that each first liquid flow channel is respectively connected to the first flow channel and the second flow channel to form a cooling liquid circulation channel.

[0068] The outer wall of the outer shell member 2 comprises an inlet 24 and an outlet 25, the inlet 24 is connected to the first flow channel, and the outlet 25 is connected to the second flow channel, the connection mode comprises direct connection or indirect connection through an inner groove, as known from the foregoing embodiments, the first flow channel, each first liquid flow channel, and the second flow channel are connected to each other and can be connected to the cooling liquid circulation system outside the box through the inlet 24 and the outlet 25 to achieve the heat dissipation and cooling of the contained battery monomer 3.

[0069] The two ends of the first groove cavity 11 are sealed and fixed, and the periphery of the inner liner member 1 is sealingly and fixedly engaged with the outer shell member 2; the sealing and fixing mode comprises brazing sealing, laser welding sealing, and resistance welding sealing.

[0070] As can be known from the foregoing embodiments, at least one maximum surface of the battery cell 3 accommodated is in heat-conducting connection with the first liquid flow channel wall, compared with the prior art in which the liquid cooling plate is arranged only on the bottom surface or top surface of the battery cell 3, the heat dissipation area of the battery cell 3 is increased, and the heat dissipation of the battery cell 3 is more balanced up and down; moreover, the first liquid flow channel is in parallel communication with the first flow channel, the inlet temperature of the cooling liquid of each first liquid flow channel is similar, the heat dissipation between different rows of batteries can be balanced, and the temperature difference of all battery cells 3 is reduced; the end area of the battery cell 3 along the y direction is relatively small, which can reduce the heat conduction between the end surfaces, in addition, the cooling liquid of the battery box of the present application includes cooling water or water-glycol cooling liquid, the boiling point of the cooling liquid is generally lower than 120℃ (the boiling point of cooling water is 100℃, the boiling point of ethylene glycol water-glycol cooling liquid is not higher than 106℃, and the boiling point of propylene glycol water-glycol cooling liquid is 102℃ to 106℃), when the first liquid flow channel is filled with cooling liquid, the conduction temperature between the battery cells 3 accommodated in the adjacent second groove cavity 12 can be limited below the gas-liquid phase change temperature of the cooling liquid, so the conduction temperature can be limited below the critical temperature 120℃ of triggering the thermal runaway of lithium battery, which shows that, in addition to being able to increase the heat dissipation area, the first liquid flow channel can also block the conduction of high temperature above 120℃ from the battery cell 3 to the battery cell 3 in the adjacent row of second groove cavities 12 when the battery cell 3 accidentally runs out of control, and the temperature below 120℃ is difficult to trigger thermal runaway immediately, therefore, the technical solution is beneficial to block the spread and diffusion of thermal runaway, in addition, the second groove cavity 12 is open upward, the smoke generated by thermal runaway can be discharged to the outside environment through the gap at the top of the battery box through the exhaust valve, the wide and smooth exhaust passage is beneficial to the rapid discharge of smoke, and is also beneficial to block the spread and diffusion of thermal runaway, and the second groove cavity 12 is open upward, which is beneficial to the assembly and maintenance of the battery cell 3.

[0071] From the foregoing embodiments, when the bottom of the battery box is damaged by scratching, the cooling liquid will leak through the damaged part via the circulation channel, and the cooling system will show an abnormal loss signal of the cooling liquid. Therefore, the bottom of the battery box should be checked in time, and the damaged bottom should be repaired in time after being found, so as to avoid the delay of sensing the scratch damage of the bottom, which may cause water seepage in the box and increase the maintenance cost. In addition, the present scheme supports the battery gravity by the shell bottom component, which can avoid the deformation of the liquid cooling plate at the bottom of the battery caused by the weight of the battery in the prior art, so that the liquid flow channel of the shell bottom is kept unobstructed. In addition, each liquid flow channel of the battery box is connected to each other through the opening at the intersection of the respective grooves 1020, thereby saving the large number of pipe joints and their sealing elements for connecting the cooling plate and the flow channel for battery side cooling in the prior art, or saving the workload of a large number of welding connection ports. During the use of the battery, the water seepage failure caused by the deformation of the interface under stress, the cracking of the weld, or the aging of the sealing ring can be reduced, and the occupied space of the large number of pipe joints can be saved, thereby improving the volume utilization rate of the battery box. The cooling liquid leakage failure can be further reduced by connecting the liquid cooling circulation system outside the box through the inlet and outlet liquid pipe interfaces arranged on the outer wall of the box. The battery box cleverly sets the cooling liquid circulation channel by combining the shell component and the lining component, which can save the configuration of the separate liquid cooling plate, cleverly set the relatively simple structure, solve the complex practical problems, achieve more superior effects, and overcome the single defects of the prior art.

[0072] In the specification, Lx is the length of the flow channel in the x direction, Ly is the length of the first groove cavity in the y direction, and h is the height of the first groove cavity 11. The cooling liquid gradually rises in the battery box along the flow process. The present inventor has found from research and practice that, when the flow process is equal, the heat dissipation area of the battery monomer 3 relative to the flow channel is 0.3-0.2 times the heat dissipation area of the battery monomer 3 relative to the liquid flow channel, and the cross-sectional area of the flow channel is usually set to be 1-0.5 times the sum of the cross-sectional areas of the liquid flow channels, so that the corresponding cooling liquid flow rate is 1-2 times the flow rate of the liquid flow channel. Therefore, when the flow process is equal, the temperature rise amplitude of the cooling liquid along the flow channel is about 0.3-0.1 times the temperature rise amplitude of the cooling liquid along the liquid flow channel. That is, the temperature rise amplitude per unit flow process of the Lx section is about 0.3-0.1 times the temperature rise amplitude per unit flow process of the Ly section.

[0073] In the following embodiments a, b, c, d, e, f, g, h, and i, various cooling liquid circulation channel specific structure modes are set to adapt to the structural characteristics of various battery boxes or battery monomers, so that all the batteries in the box can be more evenly cooled and dissipated.

[0074] In one embodiment a, (refer to Figure 3 .a; Figure 4 .a; Figure 5.a), the shell bottom member 20 includes the first recess 21 and the second recess 22 at both ends along the y direction, the liquid inlet 24 and the liquid outlet 25 are arranged at the same side of the shell member 2 along the x direction, the shortest flow path of the cooling liquid in the tank is Ly+h, the longest flow path is 2Lx+Ly+h, and the average flow path is Lx+Ly+h.

[0075] In an embodiment b, (refer to Figure 3 .a; Figure 4 .a; Figure 6 .b), the shell bottom member 20 includes the first recess 21 and the second recess 22 at both ends along the y direction, the liquid inlet 24 and the liquid outlet 25 are arranged at the same side of the shell member 2 along the x direction, the shortest flow path of the cooling liquid in the tank is Ly+h, the longest flow path is 2Lx+Ly+h, and the average flow path is Lx+Ly+h.

[0076] In an embodiment c, (refer to Figure 3 .a; Figure 7 .c; Figure 8 .c) the shell member 2 includes a first end and a second end along the y direction, the first end of the shell bottom member 20 includes the first recess 21 and the second recess 22, the first recess 21 and the second recess 22 are arranged side by side along the x direction, the second end includes the third recess 23, the third recess 23 is upwardly open, the opening of the third recess 23 intersects with the opening of each of the first groove cavities 11, and the space enclosed by the inner wall of the third recess 23 and the bottom wall of the inner lining member includes a third flow channel; the third recess and the first groove cavities are in communication with each other through the respective openings of the intersection 1020, the liquid inlet 24 and the liquid outlet 25 are arranged at the opposite sides of the shell member 2 along the x direction, and the average flow path of the cooling liquid in the tank is Lx+2Ly+h.

[0077] In an embodiment d, (refer to Figure 3 .a; Figure 9 .d; Figure 10 .d), the shell bottom member 20 includes the first recess 21 at the middle along the y direction and includes the second recess 22 at both ends, the liquid inlet 24 and the liquid outlet 25 are arranged at the same side of the shell member 2 along the x direction, the shortest flow path of the cooling liquid in the tank is 0.5Ly+h, the longest flow path is 2Lx+0.5Ly+h, and the average flow path is Lx+0.5Ly+h; the liquid inlet 24 and the liquid outlet 25 are arranged at the opposite sides of the shell member 2 along the x direction, and the flow path of the cooling liquid in the tank is Lx+0.5Ly+h.

[0078] In an embodiment e, (refer to Figure 11 .e; Figure 12 .e; Figure 13.e), the shell bottom member 20 includes a first recess 21 in the middle along the y direction, and each first groove cavity 11 includes a longitudinal partition member 101 at the half height, and the first recess 21 and the second recess 22 are arranged in parallel along the x direction, and the first recess 21 and the second recess 22 are separated by an isolation structure 201 along the y direction, and the first groove cavity 11 corresponds to the isolation structure 201 and includes a vertical partition member 102, and the vertical partition member 102 is connected to the longitudinal partition member 101 at the upper end and connected to the isolation structure 201 at the lower end, and the longitudinal partition member 101 and the vertical partition member 102 are fixedly and sealingly connected to the two side walls of the first groove cavity 11, or the longitudinal partition member 101 and the vertical partition member 102 form a corresponding partition structure by the fourth groove 114 (refer to Figure 11 .e); the first groove cavity 11 is divided into two first liquid flow channels by the longitudinal partition member 101 and the vertical partition member 102, and the two first liquid flow channels are in communication with the first and second flow channels, respectively; the cooling liquid in the first groove cavity flows in opposite directions in the two first liquid flow channels; the liquid inlet 24 and the liquid outlet 25 are arranged on the same side of the shell member 2 along the x direction, and the shortest flow path of the cooling liquid in the tank is Ly+h, the longest flow path is 2Lx+Ly+h, and the average flow path is Lx+Ly+h; the liquid inlet 24 and the liquid outlet 25 are arranged on the opposite sides of the shell member 2 along the x direction, and the flow path of the cooling liquid in the tank is Lx+Ly+h.

[0079] In an embodiment f, (reference Figure 14 .f; Figure 15 .f; Figure 16 .f), the first end of the shell bottom member 20 includes the first recess 21 and the second recess 22, the first recess 21 and the second recess 22 are arranged in parallel along the x direction, the first recess 21 and the second recess 22 are separated by an isolation structure 201 along the y direction, each first groove cavity 11 includes a longitudinal partition member 101 at the half height, and the end of the longitudinal partition member 101 is arranged at a distance from the port of the first groove cavity 11, the first groove cavity 11 corresponds to the isolation structure 201 and includes a vertical partition member 102, the vertical partition member 102 is connected to the longitudinal partition member 101 at the upper end and connected to the isolation structure 201 at the lower end, the longitudinal partition member 101 and the vertical partition member 102 are fixedly and sealingly connected to the two side walls of the first groove cavity 11, or the longitudinal partition member 101 and the vertical partition member 102 form a corresponding partition structure by the fourth groove 114 (refer to Figure 14.f), through the longitudinal separation member 101 and the vertical separation member 102, the first slot cavity 11 is divided into two first liquid flow channels, and is communicated with the first and second flow channels respectively; the cooling liquid in the two first liquid flow channels in the first slot cavity 11 flows reversely; the liquid inlet 24 and the liquid outlet 25 are arranged on the same side of the shell member 2 along the x direction, so that the shortest flow path of the cooling liquid in the tank is 2Ly+h; the longest flow path is 2Lx+2Ly+h; the average flow path is Lx+2Ly+h; the liquid inlet 24 and the liquid outlet 25 are arranged on the opposite sides of the shell member 2 along the x direction, so that the flow path of the cooling liquid in the tank is Lx+2Ly+h.

[0080] In an embodiment g, (refer to Figure 3 .a; Figure 17 .g; Figure 17 .m; Figure 17 .n;; Figure 18 .g,) the first end of the shell bottom member 20 includes the first recess 21 and the second recess 22, which are arranged in parallel along the x direction, and the second end includes the third recess 23; the first recess 21 and the second recess 22 intersect with the opening of the first slot cavity 11 at 1020, and include a flow guide member, which communicates or blocks the cooling liquid flow channel at the intersection 1020 by selecting a flow guide hole; the flow guide member includes a flow guide plate or a flow guide film; the flow guide plate includes a first flow guide plate 210 and a second flow guide plate 220, which are respectively adapted to the first recess 21 and the second recess 22, and are in sealing engagement with the shell bottom member 20 around the periphery and in sealing engagement with the bottom wall of the inner lining member 1 on the top surface; the flow guide member includes a first flow guide hole 211 corresponding to the first recess 21 and a second flow guide hole 222 corresponding to the second recess 22, which are arranged in the x direction and are staggered with each other, so that the adjacent first slot cavity 11 only communicates with one of the first recess 21 and the second recess 22 through the flow guide hole, and the cooling liquid in the adjacent first slot cavity 11 flows reversely; the liquid inlet 24 and the liquid outlet 25 are arranged on the same side of the shell member 2 along the x direction, so that the shortest flow path of the cooling liquid in the tank is 2Ly+h; the longest flow path is 2Lx+2Ly+h; the average flow path is Lx+2Ly+h; the liquid inlet 24 and the liquid outlet 25 are arranged on the opposite sides of the shell member 2 along the x direction, so that the flow path of the cooling liquid in the tank is Lx+2Ly+h.

[0081] In an embodiment h, (refer to Figure 3 .a; Figure 19 .h; Figure 20The shell bottom 20 member includes a first recess 21 in the middle of the y direction, and a second recess 22 on each side of the first recess 21 in the y direction. The first end and the second end include a third recess 23. The first recess 21 and the second recess 22 include a flow guide at the intersection 1020 with the opening of the first slot cavity 11. The flow guide includes a flow guide hole that communicates or blocks the flow path of the cooling liquid at the intersection 1020. The flow guide includes a flow guide plate or a flow guide film. The flow guide plate includes a first flow guide plate 210 and a second flow guide plate 220 that fit the first recess 21 and the second recess 22, respectively. The periphery of the flow guide plate is in sealing engagement with the shell bottom member 20, and the top surface of the flow guide plate is in sealing engagement with the bottom wall of the inner lining member 1. The flow guide includes a first flow guide hole 211 corresponding to the first recess 21 and a second flow guide hole 222 corresponding to the second recess 22. The first flow guide hole 211 and the second flow guide hole 222 are arranged in the x direction corresponding to the openings of adjacent first slot cavities 11, and are staggered with each other, so that adjacent first slot cavities 11 communicate with only one of the first recess 21 and the second recess 22 through the flow guide hole, causing the cooling liquid in the adjacent first slot cavities 11 to flow in the opposite direction. The liquid inlet 24 and the liquid outlet 25 are arranged on the same side of the outer shell member 2 in the x direction, and the shortest flow path of the cooling liquid in the tank is Ly+h. The longest flow path is 2Lx+Ly+h, and the average flow path is Lx+Ly+h. The liquid inlet 24 and the liquid outlet 25 are arranged on opposite sides of the outer shell member 2 in the x direction, and the flow path of the cooling liquid in the tank is Lx+Ly+h.

[0082] In one embodiment i, (refer to Figure 3 .a; Figure 21 .i; Figure 22In the shell bottom member 20, the first end portion includes a first recess 21 and a second recess 22 arranged in parallel along the x direction, and the second end portion includes a first recess 21 and a second recess 22 arranged in parallel along the x direction. The first recess 21 and the second recess 22 include a flow guide at the intersection 1020 of the opening of the first groove cavity 11. The flow guide is connected or blocked to the cooling liquid flow channel at the intersection 1020 by selecting a flow guide hole. The flow guide includes a flow guide plate or a flow guide film. The flow guide plate includes a first flow guide plate 210 and a second flow guide plate 220. The first flow guide plate 210 and the second flow guide plate 220 are respectively adapted to the first recess 21 and the second recess 22. The periphery of the flow guide plate is sealingly connected to the shell bottom member 20, and the top surface of the flow guide plate is sealingly connected to the bottom wall of the inner lining member 1. The flow guide includes a first flow guide hole 211 corresponding to the first recess 21 and a second flow guide hole 222 corresponding to the second recess 22. At the same end, the first flow guide hole 211 and the second flow guide hole 222 are arranged in parallel along the x direction and are staggered with each other, so that the adjacent first groove cavity 11 is connected to only one of the first recess 21 and the second recess 22 through the flow guide hole, and the cooling liquid in the adjacent first groove cavity 11 flows in the opposite direction. The liquid inlet 24 and the liquid outlet 25 are arranged on the same side of the shell member 2 along the x direction and at different ends. The shortest flow path of the cooling liquid in the tank is Ly+h. The longest flow path is 2Lx+Ly+h. The average flow path is Lx+Ly+h. The liquid inlet 24 and the liquid outlet 25 are arranged on different sides of the shell member 2 along the x direction and at different ends. The flow path of the cooling liquid in the tank is Lx+Ly+h.

[0083] The inventor has learned in the development and practice that uneven cooling can cause a large temperature difference between the battery monomers 3 for a long time, and the charging capacity attenuation is not synchronized. Especially when charging and discharging at high power, local high temperature may trigger battery thermal runaway. The charging capacity of the battery pack is usually limited by the battery monomer 3 with the fastest attenuation in it. The battery pack on the vehicle is usually provided with about 100-400 battery monomers 3. Balancing the synchronous attenuation of all battery monomers 3 can make the charging capacity be effectively utilized. The correspondence between lithium battery capacity attenuation and temperature is a prior art, which is not described in detail here.

[0084] In the foregoing embodiments a, b, d, e, f, g, h, and i, each first liquid flow channel is connected in parallel to the first and second flow channels, respectively, which can make the inlet temperature of each first liquid flow channel similar, and can cool all the batteries in the second groove cavity 12 synchronously, which can reduce the temperature difference between different rows of batteries, and is beneficial to the synchronous attenuation of the charging capacity of all battery monomers 3.

[0085] In the foregoing embodiments e and f, the cooling liquid flows reversely along the two first liquid flow channels of the first groove cavity, and the temperature rise of the cooling liquid along the flow process can be neutralized by heat conduction through the side wall and the side wall of the battery cell 3; thereby reducing the temperature difference between the battery cells 3 in the same row; this technical solution is more suitable for the scenario where the height of the battery cell is small.

[0086] In the foregoing embodiments g, h, and i, the cooling liquid in the adjacent first groove cavities 11 flows reversely, that is, the cooling liquid flows reversely along the two side surfaces of the battery cell 3, and the temperature rise of the cooling liquid along the flow process can be neutralized by heat conduction through the shell of the battery cell 3; thereby reducing the temperature difference between the battery cells 3 in the same row; this technical solution is more suitable for the scenario where the thickness of the battery cell is small.

[0087] In the foregoing embodiments b, d, e, f, g, h, and i, the cooling liquid inlet and outlet are arranged on the opposite sides of the shell member 2 along the x direction, which can make the flow process of the cooling liquid in each first groove cavity 11 the same, the flow resistance similar, and the flow rate similar; thereby balancing the heat dissipation of each row of batteries, reducing the temperature difference between different rows of batteries, and facilitating the synchronous decay of the charging capacity of all batteries; this technical solution is more suitable for the scenario where the size of the battery box along the x direction is large.

[0088] In the foregoing embodiments d and e (refer to Figure 10 .d, Figure 13 .e), a solenoid valve is connected in series on the two liquid outlet or liquid inlet branches, and the driving coil of each solenoid valve is electrically connected to the signal output port of the control panel of the battery pack thermal management system; when the battery cell occasionally overheats, the thermal management system outputs a signal to the solenoid valve, which can close the cooling liquid circulation outside the area where the thermal runaway occurs, and concentrate the flow to cool the battery in the area where the thermal runaway occurs; thereby accelerating heat dissipation and cooling, and facilitating the blocking of the spread of thermal runaway.

[0089] In the foregoing embodiment h, a vertical partitioning member is arranged between the two second flow guide holes 222 in the first groove cavity 11, which is used to block the flow of the cooling liquid along the y direction between the second flow guide holes; the vertical partitioning member includes a corresponding partitioning structure formed by the fourth groove 114, and a solenoid valve is connected in series on the two liquid outlet or liquid inlet branches; when the battery cell occasionally overheats, the solenoid valve can close the cooling liquid circulation outside the area where the thermal runaway occurs, and concentrate the flow to cool the battery in the area where the thermal runaway occurs; thereby accelerating heat dissipation and cooling, and facilitating the blocking of the spread of thermal runaway.

[0090] In the foregoing embodiments d, e, and h, the first recess 21 is arranged at the middle of the shell bottom member 20 along the y direction, which can shorten the flow of the cooling liquid in the first groove cavity, thereby reducing the temperature rise of the cooling liquid along the flow, reducing the temperature difference between the same row of battery monomers, and being more suitable for the scenario where the battery box is large in size along the y direction. In addition, by arranging the groove-shaped first recess 21 at the middle along the y direction, the rigidity of the shell bottom member 20 along the x direction can be improved, thereby improving the load capacity of the battery box.

[0091] In the foregoing embodiment c, the first recess and the second recess are arranged at the same end but on opposite sides of the shell member, so that the left and right parts of the first liquid flow channel are connected in series through the third recess. This scheme is suitable for the scenario where the battery box is large in size along the x direction and small in size along the y direction.

[0092] In an embodiment, (refer to Figure 4 .a, Figure 23 ) Corresponding to the first groove cavity 11, the shell bottom member 20 includes a third groove 213, which is open upward and parallel to the first groove cavity 11 along the y direction and opposite in opening. The third groove 213 extends to the bottom of the second groove cavity 12 along the x direction, and its two ends along the y direction are isolated or directly connected with the first recess 21, the second recess 22, or the third recess 23 on the shell bottom member. The space enclosed by the inner wall of the third groove 213 and the bottom wall of the second groove cavity 12 includes a second liquid flow channel, which is connected with the first liquid flow channel through the openings of the third groove 213 and the first groove cavity 11. The upper wall of the bottom plate of the second groove cavity 12 is in heat-conducting connection with the bottom surface of the battery monomer 3. The width of the third groove 213 is usually set to 60% to 80% of the width of the second groove cavity 12. This technical scheme can increase the heat dissipation effect of the bottom surface of the battery monomer 3 by arranging the second liquid flow channel in the third groove 213, so that the battery monomer 3 is cooled more fully and the temperature is more balanced. Especially when the thickness of the battery monomer 3 is large, the temperature equalization effect is more significant. In addition, by arranging the third groove 213, the rigidity of the shell bottom member 20 along the y direction can be improved, thereby improving the load capacity of the battery box.

[0093] In an embodiment, (refer to Figure 24 , Figure 2), the first slot cavity 11 is provided with a T-shaped slot structure in the y direction cross section, the two side walls 111 of the top of the T-shaped slot structure can cover a part or all of the top surface of the battery monomer 3 and be in thermal connection with it, and the gap between the adjacent T-shaped slot structures is provided as the upward opening of the second slot 12 cavity; this technical solution extends the top of the first slot cavity 11 along the x direction on both sides to enable the first liquid flow channel to simultaneously cool the top surface of the battery monomer 3, further increasing the heat dissipation area of the battery monomer 3, making the cooling of the battery monomer 3 more sufficient, and the temperature more balanced; in addition, when one battery monomer 3 accidentally overheats and loses control, the high-temperature flue gas generated diffuses to the lower gap of the box cover through the gap between the T-shaped slot structures, and the cooling liquid at the top of the T-shaped slot structure can limit the temperature conduction of the high-temperature flue gas to the top surface of the battery monomer 3 to be not higher than 120℃, which is beneficial to block the spread of thermal runaway through the top surface of the battery, and moreover, after the high-temperature flue gas is cooled by the cooling liquid at the top of the T-shaped slot structure, it is discharged to the environment outside the box through one or more exhaust valves arranged in the battery box, the greater the splicing area of the top of the multiple T-shaped slot structures, the more significant the cooling effect on the high-temperature flue gas, so as to reduce the probability of the high-temperature flue gas igniting the combustible material outside the box, such as the vehicle tire or the vehicle interior.

[0094] In an embodiment, (refer to Figure 3 .a, Figure 25 ), the first slot cavity 11 includes a first side plate and a second side plate, the first side plate and the second side plate are arranged at intervals along the x direction, and the first side plate and / or the second side plate include a plurality of fourth grooves 114, the fourth grooves 114 are towards the second slot cavity 12, and the plurality of fourth grooves 114 are arranged at an angle along the length direction; the two ends of the fourth grooves 114 are arranged at intervals from the two ends of the first slot cavity 11, so that the cooling liquid in each first liquid flow channel flows smoothly between the first and second flow channels; this technical solution can make the first slot cavity 11 have a moderate bearing capacity along the x direction to withstand the bulging and extrusion pressure of the battery monomer 3, avoid the first liquid flow channel being extruded and blocked, and make the first liquid flow channel persistent and unobstructed.

[0095] In an embodiment, the plurality of fourth grooves 114 are arranged at an angle along the length direction; this scheme can make the cooling liquid flowing through the first slot cavity 11 produce turbulent flow, which is beneficial to heat exchange between the cooling liquid and the battery, thereby increasing the heat dissipation effect.

[0096] In an embodiment, the plurality of fourth grooves 114 are provided as a plurality of pits, the pits are uniformly distributed on the first side plate and / or the second side plate, and the pit openings are towards the second slot cavity 12; this scheme can make the cooling liquid flowing through the first slot cavity 11 produce turbulent flow, which is beneficial to heat exchange between the cooling liquid and the battery, thereby increasing the heat dissipation effect.

[0097] In an embodiment, the fourth groove 114 is filled with an elastic glue 112, which is bonded to the wall of the fourth groove 114; the elastic glue 112 includes rubber strips, thick adhesive tapes, heat-conductive glue, structural glue, and sealing glue; this technical solution can further improve the bearing capacity of the first groove cavity 11 along the x direction, and the elastic deformation can offset the slight expansion of the battery monomer 3 along the x direction, and give it a moderate restraining force, so that the first liquid flow channel is always unobstructed.

[0098] In an embodiment, the inner lining member 1 is made of a stainless steel sheet material, and the wall thickness of the first groove cavity 11 is not greater than 0.5 mm; compared with the prior art, the inner lining member 1 in this technical solution is made of a stainless steel sheet material, so that the battery box has longer corrosion resistance and higher temperature resistance; in particular, in the case of accidental thermal runaway of the battery monomer 3, the inner lining member 1 can avoid being melted by high temperature caused by thermal runaway, so that the cooling of the thermal runaway battery monomer 3 is more stable; in addition, the inner lining member 1 is made of a sheet material with a thickness of not greater than 0.5 mm, which is beneficial to the heat conduction between the surface of the battery monomer 3 and the cooling liquid; in addition, the inner lining member 1 is made of a 0.5 mm thick stainless steel sheet, which can make the inner lining member 1 have the ability to withstand greater vibration impact, so as to adapt to the scene of heavy electric trucks and other running with intense vibration.

[0099] In an embodiment, the inner lining member 1 is made of a stainless steel sheet with a thickness of not less than 0.02 mm, which can reduce the weight of the battery box as much as possible to adapt to the scene of high weight reduction requirement in aerospace, such as high-power aircraft or space station, etc. Although the heat conduction performance of stainless steel is not good, the thickness of the stainless steel sheet used can be as low as 0.02 mm, and the actual product heat dissipation speed can be designed to be equivalent to that of an inner lining member made of an aluminum alloy sheet.

[0100] In an embodiment, a battery pack, comprising a plurality of battery monomers 3, the battery monomers 3 comprising square shell batteries or soft package batteries, a heat insulation film is arranged between the end faces of the battery monomers 3, the heat insulation film comprises aerogel film or mica sheet, the battery pack comprises the aforementioned battery box, the battery pack comprises one or more box bodies, the plurality of box bodies are arranged along the x direction and / or along the y direction, or are stacked along the z direction; this technical solution can synchronously cool the four surfaces of the battery monomers 3 at most, the non-radiation surface blocks high temperature conduction through the heat insulation film, compared with the prior art, the battery pack increases the heat dissipation area of the battery monomers 3, makes the heat dissipation of the battery monomers 3 more balanced and efficient, is beneficial to the implementation of high-power charging and discharging of the battery, can block the conduction of each surface temperature of the battery monomer higher than 120℃, is beneficial to block the spread and diffusion of thermal runaway of a single battery to the remaining battery monomers 3; the arrangement of the plurality of box bodies along the x direction and / or along the y direction is suitable for installing the battery pack at the bottom of the vehicle, such as installing at the bottom of the electric car, electric SUV, electric light truck, electric light bus, the arrangement of the plurality of box bodies along the z direction is suitable for installing the battery pack on the heavy electric truck and electric ship or in the energy storage cabinet, in an embodiment, the plurality of box bodies can be arranged in the battery pack as a plurality of battery module housings, this battery pack has the same technical effects as the aforementioned beneficial to block the spread and diffusion of thermal runaway of the battery monomer.

[0101] In an embodiment, the battery pack comprises an electrical connection member between the same row adjacent battery monomers 3, the electrical connection member is located at the top of the battery monomer 3, the surface of the electrical connection member is in electrically insulated and heat conductive connection with the top wing wall 111 of the T-shaped groove structure 111 of the first groove cavity 11; this technical solution can cool the electrical connection member through the heat conduction between the surface of the electrical connection member and the T-shaped groove wing wall 111, improve the current-carrying capacity of the electrical connection member during high-power charging and discharging of the battery, reduce the heat conduction from a single battery to the same row adjacent battery via the electrical connection member during the accidental thermal runaway of the single battery, and the T-shaped groove wing wall 111 can block the thermal runaway eruption material from covering the electrical connection member, thereby realizing thermal and electrical separation, reducing short circuit failure, thereby being beneficial to block the spread and diffusion of thermal runaway caused by high temperature conduction.

[0102] In an embodiment, a plurality of liquid outlet branches or liquid inlet branches of the battery pack are connected in series with solenoid valves, the driving coil of each solenoid valve is respectively electrically connected with the signal output port of the controller of the thermal management system of the battery pack, the solenoid valve usually adopts a normally open solenoid valve, this technical solution can close the cooling liquid circulation outside the area where the thermal runaway occurs by outputting the signal of the thermal management system to the solenoid valve when the thermal runaway occurs in the battery pack, can concentrate the flow to cool the battery in the area where the thermal runaway occurs, can accelerate the heat dissipation and cooling, and is beneficial to block the spread and diffusion of thermal runaway.

[0103] In an embodiment, the top of the battery cell 3 is coated with a thermal insulation material or covered with a thermal insulation film, which includes an aerogel film, and a weak breaking groove is arranged corresponding to the explosion-proof valve of each battery cell 3, the breaking groove includes a straight or cross breaking line, so that the battery cell 3 can smoothly vent when it accidentally overheats, and the heat of the high-temperature flue gas is blocked from being conducted to the remaining battery cells 3 through the top surface, thereby facilitating the blocking of the spread of thermal runaway. This scheme can be applied to the scenario where the top of the first groove 11 has no wing wall 111.

[0104] In an embodiment, an electric vehicle includes a liquid cooling circulation system and the aforementioned battery pack, the battery pack includes a box cover, a thermal insulation film is arranged on the inner wall of the box cover, the thermal insulation film includes an aerogel film or a mica sheet, the battery pack is arranged at the bottom of the electric vehicle, the liquid inlet 24 and the liquid outlet 25 of the battery pack are respectively connected to the vehicle-mounted liquid cooling circulation system through pipelines, and the battery pack provides driving electric energy for the electric vehicle; the vehicle-mounted battery pack can block the high-temperature flue gas generated by thermal runaway from igniting the combustible materials in the vehicle by arranging a thermal insulation film on the inner wall of the box cover, and the cooling liquid in the second liquid flow channel of the shell bottom can limit the temperature of the high-temperature flue gas discharged during thermal runaway to be not higher than 120℃, thereby the aforementioned electric vehicle is beneficial to block the spread of thermal runaway and reduce the probability of igniting the vehicle due to a single battery thermal runaway; in addition, if the battery pack is damaged and leaks due to accidental scratching of the vehicle bottom, the cooling liquid leakage loss signal of the vehicle-mounted liquid cooling circulation system is sensed, the vehicle bottom is checked in time, and the damaged part is found and repaired, which can avoid the expansion of repair cost due to delayed sensing of damage and water infiltration in the battery pack.

[0105] In addition, the maximum of two side surfaces of the aforementioned battery cell 3 can be cooled by the cooling liquid, and the four surfaces including the top surface and the bottom surface can be cooled, which can balance the heat dissipation of the battery cell 3, reduce the temperature difference, and reduce the probability of triggering thermal runaway due to excessive temperature rise. In addition, even if thermal runaway occurs, due to the sufficient and rapid cooling of the battery cell 3, the explosion intensity of the thermal runaway is reduced, and the spread of the thermal runaway is blocked.

[0106] In the foregoing embodiment, the battery box has the advantages that it can at most liquid-cool four surfaces of the battery monomer, and at least the largest surface of the battery can be liquid-cooled, the heat dissipation area is increased, the battery is more fully and evenly cooled, various structures of the liquid flow channel are arranged to adapt to the structural characteristics of various battery boxes or battery monomers, the temperature difference of all the batteries in the box is smaller, which is beneficial to synchronous attenuation of all the batteries and effective utilization of the battery capacity; in addition, the battery box can liquid-cool multiple surfaces of the battery monomer through the liquid flow channel, and the liquid flow channel can limit high-temperature conduction in case of accidental overheating, which is beneficial to blocking the spread of thermal runaway, and the battery box does not need cooling liquid pipelines and pipe interfaces, which can reduce liquid leakage failure and the occupied space, and improve the volume utilization rate of the battery box; in addition, the vehicle-mounted battery box can discover the scratch damage of the box bottom in time through sensing the cooling liquid leakage loss signal, so as to avoid the expansion of the loss due to sensing delay; compared with the prior art, the technical scheme has more comprehensive beneficial effects.

[0107] Nowadays, the energy consumption of data center circuit modules is increasing, and the method of immersing the circuit module in electrically insulating heat-conducting liquid can efficiently cool the circuit module. However, the electrically insulating heat-conducting liquid is easily contaminated in the cooling circulation process, which reduces its electrically insulating performance, and when the electrically insulating performance is not up to standard, all the electrically insulating heat-conducting liquid in a single cooling system needs to be replaced, which increases the operating cost of the data center; the present scheme aims to solve at least one problem in the prior art and provides a circuit module cooling box that can reduce the risk of contamination of electrically insulating heat-conducting liquid.

[0108] In an embodiment, (refer to Figure 26 .a, Figure 26 .b), a circuit module 4 cooling box, comprising a top-opened box body, the box body comprising an outer shell member 2 and an inner lining member 1, the inner lining member 1 being arranged in a bent structure, comprising a plurality of bent structures of single-layer sheet material arranged in the x direction to form a first slot cavity 11 with an opening downward and a second slot cavity 12 adjacent to the first slot cavity 11 and with an opening upward, the inner lining member 1 comprising a plurality of the first slot cavities 11 and the second slot cavities 12 arranged in the x direction, extending in the y direction, parallel to each other and alternately arranged, the first slot cavity 11 comprising a first liquid flow channel, the second slot cavity 12 accommodating a circuit module 4 and electrically insulating heat-conducting liquid, at least a part of the circuit module 4 being immersed in the electrically insulating heat-conducting liquid, the accommodated circuit module 4 being in heat-conducting connection with the wall plate of the first liquid flow channel through the electrically insulating heat-conducting liquid, the electrically insulating heat-conducting liquid in each second slot cavity 12 being isolated from each other and not flowing,

[0109] The shell member 2 comprises a shell bottom member 20, the bottom wall of the inner liner member 1 is assembled with the inner wall of the shell bottom member 20, the shell member 2 comprises a first end and a second end along the y direction, the first end of the shell bottom member 20 comprises a first recess 21, the second end comprises a second recess 22, or the first recess 21 is arranged at the middle part of the shell bottom member 20 along the y direction, and the second recess 22 is arranged at the two end parts along the y direction, the opening of the first recess 21 and the second recess 22 faces upward, and each first groove cavity 11 is intersected with the opening, respectively, the space formed by the inner wall of the first recess 21 and the bottom wall of the inner liner member 1 comprises a first flow channel, the space formed by the inner wall of the second recess 22 and the bottom wall of the inner liner member 1 comprises a second flow channel, and each first groove cavity 11 is connected with the first recess 21 and the second recess 22 at the intersection 1020 through the opening, respectively; each first flow channel is connected with the first flow channel and the second flow channel, respectively, to form a cooling liquid circulating channel, the outer wall of the shell member 2 comprises a liquid inlet 24 and a liquid outlet 25, the liquid inlet 24 and the liquid outlet 25 are directly connected with the first flow channel and the second flow channel, respectively, or are indirectly connected through the groove cavity channel.

[0110] The two ends of the first groove cavity 11 along the y direction are sealed and fixed, and the periphery of the inner liner member 1 is sealingly and fixedly connected with the shell member 2; the sealing and fixing mode comprises brazing sealing, laser welding sealing and resistance welding connection.

[0111] In an embodiment, the first groove cavity 11 comprises a first side plate and a second side plate, the first side plate and the second side plate are planar plate structures and are arranged at intervals along the x direction, or the first side plate and / or the second side plate are profiled plate structures, the profiled first side plate and / or the profiled second side plate comprise a plurality of fourth grooves 114, the fourth grooves 114 face the second groove cavity 12, and the plurality of fourth grooves 114 are arranged at a horizontal angle or an inclined angle along the length direction.

[0112] The technical scheme can conduct heat conduction between the cooling liquid and the electrically insulated heat-conducting liquid, cool the circuit module 4, and isolate the cooling liquid and the electrically insulated heat-conducting liquid through the first groove cavity wall, so that the electrically insulated heat-conducting liquid does not participate in the circulation of the cooling liquid, the probability of pollution and degradation of the electrically insulated heat-conducting liquid can be reduced, and the electrically insulated heat-conducting liquid in each second groove cavity 12 is isolated and does not flow, so that when the electrically insulated heat-conducting liquid needs to be replaced synchronously due to an occasional fault of the circuit module 4, only the electrically insulated heat-conducting liquid in the second groove cavity 12 needs to be replaced, and the cost of related liquid replacement can be reduced; in addition, the plurality of fourth grooves 114 arranged on the side plate of the first groove cavity 11 can increase the heat exchange area of the cooling liquid and the electrically insulated heat-conducting liquid, and further improve the heat dissipation efficiency.

Claims

1. A battery case comprising a top-opened case body which can accommodate a plurality of battery cells, characterized by The box body comprises an outer shell member and an inner liner member, the inner liner member is arranged in a bent structure to form a first slot cavity with an opening downward and a second slot cavity adjacent to the first slot cavity and with an opening upward, the inner liner member comprises a plurality of the first slot cavities and the second slot cavities arranged along an x direction, the cross sections of the slot cavities extend along a y direction, the first slot cavities and the second slot cavities are arranged alternately and parallel to each other, the first slot cavities comprise first liquid flow channels, the second slot cavities comprise battery accommodating slots, and at least one maximum surface of the accommodated battery monomer is in heat conduction connection with the wall of the first liquid flow channel; The outer shell member comprises a shell bottom member, the inner wall of the shell bottom member is assembled with the bottom wall of the inner liner member, the shell bottom member comprises a first recess and / or a second recess at both ends or in the middle along the y direction, the first recess and the second recess are upwardly open, and the openings of the first recess and the second recess respectively intersect with the openings of each of the first slot cavities, the space formed by the inner wall of the first recess and the bottom wall of the inner liner member comprises a first flow collecting channel, the space formed by the inner wall of the second recess and the bottom wall of the inner liner member comprises a second flow collecting channel, each of the first slot cavities is in communication with the first recess and the second recess at the intersection through the openings thereof respectively, so that each of the first liquid flow channels is in communication with the first flow collecting channel and the second flow collecting channel respectively to form a cooling liquid circulating channel; the outer wall of the outer shell member comprises an inlet and an outlet, the inlet is in communication with the first flow collecting channel, and the outlet is in communication with the second flow collecting channel; Both ends of the first slot cavity are sealed and fixedly sealed, and the periphery of the inner liner member is sealingly and fixedly engaged with the outer shell member.

2. The battery box of claim 1, wherein The specific structural mode of the cooling liquid circulating channel of the battery box comprises any one of the following modes; a. The shell bottom member comprises the first recess and the second recess at both ends along the y direction respectively, and the inlet and the outlet are arranged on the same side of the outer shell member along the x direction respectively; b. The shell bottom member comprises the first recess and the second recess at both ends along the y direction respectively, and the inlet and the outlet are arranged on different sides of the outer shell member along the x direction respectively; c. The outer shell member comprises a first end and a second end along the y direction, the first end comprises the first recess and the second recess arranged side by side along the x direction, the inlet and the outlet are arranged on different sides of the outer shell member along the x direction respectively, and the second end comprises a third recess, the third recess is upwardly open, the opening of the third recess intersects with the opening of each of the first slot cavities, and the space formed by the inner wall of the third recess and the bottom wall of the inner liner member comprises a third flow collecting channel; the third flow collecting channel is in communication with the first liquid flow channel through the openings at the intersection; d. The shell bottom member comprises the first recess in the middle along the y direction and the second recess at both ends respectively, and the inlet and the outlet are arranged on the same side or different sides of the outer shell member along the x direction respectively. e. The shell bottom member includes a first recess in the middle along the y direction, and each first recess includes a second recess on both sides along the y direction, and the recesses include isolation structures. At each half-height position of the first groove cavity, the front section and the rear section each include a longitudinal separation member, and the corresponding isolation structures include vertical separation members. The longitudinal separation members and the vertical separation members separate the front section and the rear section of the first groove cavity into two first liquid flow channels above and below, and are respectively connected to the first and second flow channels, so that the cooling liquid in the two first liquid flow channels above and below flows in opposite directions; the liquid inlet and the liquid outlet are respectively arranged on the same side or on the opposite side of the shell member along the x direction; f. The first end of the shell bottom member includes the first recess and the second recess arranged in parallel along the x direction, and the recesses include isolation structures. At each half-height position of the first groove cavity, the longitudinal separation member is included, and the corresponding isolation structures include vertical separation members. The longitudinal separation members and the vertical separation members separate the first groove cavity into two first liquid flow channels above and below, and are respectively connected to the first and second flow channels, so that the cooling liquid in the two first liquid flow channels above and below flows in opposite directions; the liquid inlet and the liquid outlet are respectively arranged on the same side or on the opposite side of the shell member along the x direction; g. The first end of the shell bottom member includes the first recess and the second recess arranged in parallel along the x direction, and the second end includes the third recess. The first recess and the second recess include flow guides at the intersection with the opening of the first groove cavity. The flow guides are connected or blocked to the cooling liquid flow channel at the intersection by selecting flow guide holes. The first groove cavity is sequentially and staggeredly connected to the first recess and the second recess, so that the cooling liquid of adjacent first groove cavities flows in opposite directions. The liquid inlet and the liquid outlet are respectively arranged on the same side or on the opposite side of the shell member along the x direction; h. The shell bottom member includes a first recess in the middle along the y direction, and each first recess includes a second recess on both sides along the y direction, and the recesses include isolation structures. At each half-height position of the first groove cavity, the front section and the rear section each include a longitudinal separation member, and the corresponding isolation structures include vertical separation members. The longitudinal separation members and the vertical separation members separate the front section and the rear section of the first groove cavity into two first liquid flow channels above and below, and are respectively connected to the first and second flow channels, so that the cooling liquid in the two first liquid flow channels above and below flows in opposite directions; the liquid inlet and the liquid outlet are respectively arranged on the same side or on the opposite side of the shell member along the x direction; i. The first end of the shell bottom member includes a first recess and a second recess arranged in parallel along the x direction, and the second end includes the first recess and the second recess arranged in parallel along the x direction. The first recess and the second recess intersect with the first groove cavity opening and include flow guides. The flow guides are connected or blocked to the opening intersection cooling liquid flow channel through the selected flow guide holes. The first groove cavity staggered communicates with the first recess and the second recess in sequence at the same end, causing the cooling liquid of adjacent first groove cavities to flow in opposite directions. The liquid inlet and the liquid outlet are arranged on the same side or different sides of the shell member along the x direction.

3. The battery pack of claim 1, wherein The shell bottom member includes a third recess. The third recess is upwardly open and parallel to the first groove cavity along the y direction and oppositely open. The third recess extends to the bottom of the second groove cavity along the x direction. The inner wall of the third recess and the bottom wall of the second groove cavity form a second liquid flow channel. The second liquid flow channel and the first liquid flow channel are connected to each other through the third recess opening and the first groove cavity opening. The upper wall of the second groove cavity bottom plate is in thermal conductive connection with the bottom surface of the battery cell.

4. The battery pack of claim 1, wherein The first groove cavity has a T-shaped groove structure in cross-section along the y direction. The two side walls of the top of the T-shaped groove structure cover at least a portion of the top surface of the battery cell and are in thermal conductive connection therewith.

5. The battery pack of claim 1, wherein The first groove cavity includes a first side plate and a second side plate arranged at intervals along the x direction. The first side plate and / or the second side plate include a plurality of fourth recesses. The fourth recesses are open toward the second groove cavity. The fourth recesses are arranged at a horizontal angle along the length direction; or the plurality of fourth recesses are arranged at an oblique angle along the length direction. Alternatively, the plurality of fourth recesses are arranged as a plurality of circular or elliptical recesses. The recesses are open toward the second groove cavity and are uniformly arranged on the first side plate and / or the second side plate.

6. A battery pack comprising a plurality of battery cells, a heat insulating film being provided between end faces in a y direction of the battery cells, characterized by The battery pack includes the battery box according to any one of claims 1 to 5. The battery pack includes one or more box bodies. The plurality of box bodies are arranged along the x direction and / or along the y direction, or are stacked along the z direction.

7. The battery pack of claim 6, wherein A plurality of liquid outlet pipe branches of the battery pack are respectively connected in series with electromagnetic valves, or a plurality of liquid inlet pipe branches are respectively connected in series with electromagnetic valves.

8. An electric vehicle comprising an on-board liquid cooling system, characterized in that The electric vehicle includes the battery pack according to claim 6 or 7. The battery pack includes a box cover. The inner wall of the box cover is covered with thermal insulation material. The battery pack is arranged at the bottom of the electric vehicle. The liquid inlet and the liquid outlet of the battery pack are respectively connected to the vehicle-mounted liquid cooling circulation system through pipelines. The battery pack provides driving electric energy for the electric vehicle.

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