Battery pack and vehicle

Abstract

A battery pack (1000) and a vehicle. The battery pack (1000) comprises a box body assembly (100), an upper cover (300), a battery cell assembly (200), a control assembly (500), a first plate member (10), and a second plate member (20). The box body assembly (100) comprises a frame (110) and a first cross beam (120), and an inner cavity of the frame (110) is divided into a control compartment (101) and a main mounting area (102) by means of the first cross beam (120). An explosion-proof valve (30) is provided on the frame (110). The first plate member (10) sealingly covers an upper opening of the main mounting area (102), the second plate member (20) sealingly covers a lower opening of the inner cavity of the frame (110), the upper cover (300) sealingly covers an upper opening of the inner cavity of the frame (110), and the first plate member (10) is provided with a wiring channel (11) and a wiring sealing member (12). Independent closed spaces are isolated by means of the box body assembly (100), the first plate member (10), and the second plate member (20) for mounting the battery cell assembly (200), and the first plate member (10) separates the control assembly (500) and a conductive member (230) used for connecting the control assembly (500) to the battery cell assembly (200) from the battery cell assembly (200), thereby preventing problems such as adhesion of electronic components in the interior of the control assembly (500) and short circuiting of wiring harnesses caused by high-temperature smoke generated during thermal runaway of a battery cell, achieving thermoelectric separation, and improving the safety of the battery pack (1000).

Description

Battery pack and vehicle Cross-reference to related applications

[0001] This application claims priority to Chinese Patent Application No. 202410897939.6, filed on July 5, 2024, the entire contents of which are incorporated herein by reference. TECHNICAL FIELD

[0002] The present application belongs to the technical field of battery packs, and in particular relates to a battery pack and a vehicle. BACKGROUND

[0003] With the rapid development of new energy vehicles, the safety of battery packs is becoming increasingly important. When a battery cell in a battery pack experiences thermal runaway, it can quickly spread to adjacent battery cells. When the internal pressure of the battery cell rises to a certain level, or the internal structure of the battery cell is broken, the battery cell may explode or release toxic gas. The thick smoke released by the battery cell contains conductive particles, and the diffusion of these conductive particles into the entire battery pack can cause secondary short circuits, leading to more severe thermal runaway. SUMMARY

[0004] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, the present application proposes a battery pack and a vehicle, which realizes directional exhaust when the battery pack experiences thermal runaway, timely exhausts the smoke outside the battery pack, avoids contact with the circuit board, and reduces the risk of thermal runaway.

[0005] In a first aspect of the present application, a battery pack is provided, comprising:

[0006] A box assembly comprising a frame and a first cross beam arranged in the frame, the inner cavity of the frame is divided into a control cabin and a main installation area by the first cross beam; at least one explosion-proof valve for communicating the main installation area with the outside is arranged on the frame;

[0007] An upper cover sealingly connected to the box assembly and covering the upper opening of the inner cavity of the frame;

[0008] A first plate and a second plate are arranged in the lower part of the upper cover;

[0009] A battery cell assembly arranged in the main installation area;

[0010] A control assembly arranged in the control cabin and electrically connected to the battery cell assembly through a conductive member;

[0011] The first plate is sealingly connected to the box assembly and covers the upper opening of the main mounting area, and the second plate is sealingly connected to the box assembly and covers the lower opening of the inner cavity of the frame, so that the main mounting area and the control cabin form a mutually independent space; the first plate is provided with a wire passing channel for the conductive member to pass through, and a wire passing sealing member is arranged in the gap between the conductive member and the wire passing channel.

[0012] In some optimized technical solutions, the box assembly further comprises at least one second cross beam and at least one longitudinal beam arranged in the frame, and the second cross beam and the longitudinal beam are located in the main mounting area and separate the main mounting area into a plurality of battery cabins.

[0013] The first plate and the second plate are sealingly connected to the second cross beam and the longitudinal beam, so that each battery cabin forms a closed and mutually independent space.

[0014] The cell assembly comprises a plurality of cell modules electrically connected by a connecting copper bar, and each of the plurality of cell modules is arranged in one of the plurality of battery cabins.

[0015] In some optimized technical solutions, the upper cover is arranged in a spaced-apart manner with the first plate to enclose a wiring space in communication with the control cabin; the connecting copper bar and the conductive member both extend into the wiring space through the wire passing channel and are sealed by the wire passing sealing member.

[0016] In some optimized technical solutions, the control assembly comprises a control device and a power distribution device electrically connected, and the conductive member comprises an output copper bar for connecting the cell assembly and the power distribution device, and a low-voltage sampling wire harness for connecting the cell assembly and the control device.

[0017] In some optimized technical solutions, the wire passing channel comprises a plurality of first through holes, a plurality of second through holes and a plurality of third through holes arranged in a spaced-apart manner; the output copper bar extends into the first through hole, the connecting copper bar extends into the second through hole, and the low-voltage sampling wire harness extends into the third through hole.

[0018] In some optimized technical solutions, the first through holes and the second through holes are arranged at the edges of the first plate; and the third through holes are arranged at the edges and / or the middle of the first plate.

[0019] In some optimized technical solutions, the first plate is provided with a reinforcing rib, and the wire passing channel is arranged in the reinforcing rib.

[0020] In some preferred embodiments, the first cross beam, the second cross beam, the longitudinal beam and the side cross beam of the frame are all provided with sealing pads, and the first plate, the box assembly and the second plate jointly compress the sealing pads.

[0021] In some preferred embodiments, the upper cover and the second plate are both connected with the box assembly FDS, and the connection part is coated with sealing glue; the upper cover applies a force to the first plate for compressing the sealing pads.

[0022] In some preferred embodiments, the first plate is connected with the box assembly FDS or connected through a screw, and the connection part is coated with sealing glue; or, the upper cover is welded with the first plate as a whole.

[0023] In some preferred embodiments, the inner wall of the box assembly is provided with at least one one-way valve corresponding to the position of the main mounting area, the explosion-proof valve is arranged on the outer wall of the frame, the frame and the first cross beam both have exhaust channels connected with each other, and the one-way valve and the explosion-proof valve are both connected with the exhaust channels.

[0024] In some preferred embodiments, the second cross beam and / or the longitudinal beam also have the exhaust channels, and the exhaust channels of the second cross beam and / or the longitudinal beam are connected with the exhaust channels of the frame.

[0025] In some preferred embodiments, the one-way valve and the explosion-proof valve are both arranged on the frame and correspond to the battery compartments one by one; the one-way valve and the explosion-proof valve are distributed in a staggered manner.

[0026] In some preferred embodiments, the battery pack further comprises a cooling assembly, the cooling assembly comprises an upper liquid cooling plate and a lower liquid cooling plate, the upper liquid cooling plate and the lower liquid cooling plate respectively constitute the first plate and the second plate; the battery cell assembly is arranged on the lower liquid cooling plate.

[0027] In some preferred embodiments, the upper liquid cooling plate and the lower liquid cooling plate both comprise a plane plate and a flow channel plate, the flow channel plate faces the battery cell assembly; the plane plate and the flow channel plate are both provided with reinforcing ribs, the edges of the plane plate and the flow channel plate and the positions where the reinforcing ribs are located are welded; the wire passing channel is arranged in the reinforcing rib.

[0028] In some preferred embodiments, the battery cell of the battery cell assembly is a soft-pack battery cell or a cylindrical battery cell.

[0029] In the second aspect of the present application, a vehicle is provided, comprising the battery pack of the first aspect.

[0030] According to one or more embodiments of the present application, the battery pack is provided. By arranging the box assembly, the first plate and the second plate, the control cabin and the main installation area are formed independently. The control cabin is used for installing the control assembly, and the main installation area is used for installing the cell assembly. The frame is provided with an explosion-proof valve for communicating the main installation area with the outside. When thermal runaway occurs in the cell assembly, high-temperature flue gas can be discharged out of the battery pack through the explosion-proof valve. Since the main installation area is enclosed by the frame, the first cross beam, the first plate and the second plate, the high-temperature flue gas cannot pass through the main installation area and cannot enter the control cabin, thereby avoiding the situation that the control assembly is in contact with the high-temperature flue gas and short-circuit or internal electronic components are adhered and cannot be connected to high-voltage electricity, and reducing the risk of thermal runaway. Since the main installation area is a closed space, in order to facilitate the electrical connection between the control assembly and the cell assembly, the first plate is provided with a wire passing channel for the conductive piece to pass through, and a wire passing sealing piece is arranged in the gap between the conductive piece and the wire passing channel, which not only ensures the sealing of the main installation area, but also allows the wire to pass through the gap between the upper cover and the first plate, preventing the high-temperature flue gas from adversely affecting the conductive piece.

[0031] Therefore, according to one or more embodiments of the present application, the battery pack is provided. The box assembly, the first plate and the second plate isolate an independent sealed space for installing the cell assembly. At the same time, the first plate separates the control assembly and the conductive piece for connecting the control assembly and the cell assembly from the cell assembly, thereby preventing the high-temperature flue gas generated when the cell is in thermal runaway from causing the internal electronic components of the control assembly to adhere and the wire harness to short-circuit, and realizing thermal and electrical separation and improving the safety of the battery pack. BRIEF DESCRIPTION OF DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without any creative effort.

[0033] FIG. 1 shows an exploded view of the battery pack in one or more embodiments of the present application. In order to facilitate the display of the control cabin, the control assembly is hidden.

[0034] FIG. 2 shows a structural schematic diagram of the battery pack in one or more embodiments of the present application after the upper cover is removed.

[0035] FIG. 3 shows a structural schematic diagram of the first plate in the battery pack of FIG. 2.

[0036] FIG. 4 shows an assembly structure diagram of the copper bar and the first plate in the battery pack of FIG. 2.

[0037] FIG. 5 shows an assembly structure diagram of the box assembly and the second plate in the battery pack of FIG. 2.

[0038] Fig. 6 shows a structural diagram of a cell module of a battery pack in one or more embodiments of the present application.

[0039] Fig. 7 shows a schematic diagram of an exhaust path of a battery pack in one or more embodiments of the present application.

[0040] Fig. 8 shows a cross-sectional view of Fig. 7 along A-A.

[0041] Fig. 9 shows an assembly structure diagram of a frame and a first cross beam of a battery pack in one or more embodiments of the present application.

[0042] Fig. 10 shows a structural diagram of a front side of an upper liquid cooling plate of a battery pack in one or more embodiments of the present application.

[0043] Fig. 11 shows a structural diagram of a back side (a side where a flow channel is located) of an upper liquid cooling plate of a battery pack in one or more embodiments of the present application.

[0044] Legend of reference signs:

[0045] 1000 - battery pack; 10 - first plate member, 11 - wire passage, 11a - first through hole, 11b - second through hole, 11c - third through hole, 12 - wire sealing member; 20 - second plate member; 30 - explosion-proof valve; 40 - one-way valve; 50 - sealing gasket; 100 - box assembly, 101 - control cabin, 102 - main mounting area, 103 - battery cabin, 104 - exhaust passage; 110 - frame, 111 - frame longitudinal beam, 112 - mounting portion; 120 - first cross beam; 130 - second cross beam; 140 - longitudinal beam; 150 - mounting bracket; 160 - partition plate; 200 - cell assembly, 210 - cell module, 211 - high-voltage connection site, 212 - low-voltage sampling port, 220 - connection copper bar, 230 - conductive member, 231 - output copper bar, 232 - low-voltage sampling wire harness; 300 - upper cover; 410 - upper liquid cooling plate, 411 - flat plate, 412 - flow channel plate, 413 - reinforcing rib, 414 - flow channel; 420 - lower liquid cooling plate; 500 - control assembly; 510 - control device; 520 - power distribution device; 600 - bottom guard plate. DETAILED DESCRIPTION

[0046] In order for those skilled in the art to which the present application pertains to more clearly understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0047] In the related art, the most common pressure relief method in a battery pack is to assemble an explosion-proof valve on the battery pack boundary beam, the explosion-proof valve connects the internal space of the battery pack with the external environment, when thermal runaway occurs, the internal pressure of the battery pack increases, and when the threshold of the explosion-proof valve is reached, the explosion-proof valve is opened, and the high-temperature substances in the battery pack are released. In the existing scheme, the whole battery pack cavity is connected, and after thermal runaway occurs, before the explosion-proof valve is opened, thermal runaway can easily spread from the local to the whole battery pack, causing the whole battery pack to catch fire and explode, causing serious losses. The smoke generated by the battery cell spreads, and the conductive substances in it can cause secondary short circuit of the BDU and other battery modules, causing more severe thermal runaway, for example: high-temperature smoke causes the BDU internal relay to stick and cannot turn on and off high-voltage electricity; conductive substances in high-temperature smoke adhere to the low-voltage connection point of the BMS, causing inaccurate detection signals; high-temperature smoke causes the low-voltage connection point of the BMS to short circuit, causing the BMS internal circuit board to be damaged due to excessive voltage, etc.

[0048] The existing technology mainly focuses on how to realize the directional eruption of high-temperature smoke when the battery cell thermal runaway occurs, so as to prevent the spread of thermal runaway. Some related technologies set an exhaust channel in the battery pack box, and place the battery cell in a posture with the battery cell explosion-proof valve facing the exhaust channel. When thermal runaway occurs, the gas ejected by the battery cell explosion-proof valve will be directly guided to the box explosion-proof valve through the guide flue and discharged outside the battery pack, so as to realize the directional eruption of high-temperature smoke into the exhaust channel when the battery cell thermal runaway occurs, and avoid the spread in the battery pack. This technology is only suitable for square cell battery cells with explosion-proof valves, and is not suitable for soft package battery cells and cylindrical battery cells without explosion-proof valves. Since thermal and electrical separation has not been achieved, there are still problems such as contact between high-temperature smoke and control components causing internal electronic components of the control components to stick and wire harness short circuit.

[0049] Therefore, one or more embodiments of the present application provide a battery pack and a vehicle, which can at least solve the technical problems existing in the related art to a certain extent, and are suitable for all types of battery cells without requiring battery cell types and structures. The technical solutions of the present application will be described in detail below in combination with the drawings and embodiments.

[0050] Referring to FIG. 1, the first aspect of the present application provides a battery pack 1000, which comprises a box assembly 100, a first plate 10, a second plate 20, a cell assembly 200, an upper cover 300 and a control assembly 500. The box assembly 100 comprises a frame 110 and a first cross beam 120 connected to the frame 110. The frame 110 is provided with a mounting hole for connecting a vehicle to install the battery pack 1000 on the vehicle. The first cross beam 120 is arranged in the frame 110, and the inner cavity of the frame 110 is divided into a control cabin 101 and a main installation area 102 by the first cross beam 120, as shown in FIG. 5. The cell assembly 200 is arranged in the main installation area 102 of the box assembly 100, and the control assembly 500 is arranged in the control cabin 101 of the box assembly 100. The control assembly 500 is electrically connected to the cell assembly 200 through a conductive member 230, and the conductive member 230 is used to transmit high-voltage current and / or low-voltage detection signals.

[0051] The upper cover 300 is sealingly connected to the box assembly 100, and the upper cover 300 covers the upper opening of the inner cavity of the frame 110. The first plate 10 and the second plate 20 are arranged below the upper cover 300. The second plate 20 is sealingly connected to the box assembly 100 and covers the lower opening of the inner cavity of the frame 110. The upper cover 300, the box assembly 100 and the second plate 20 form a whole package sealing of the battery pack 1000, which meets the IP67 sealing requirement of the battery pack 1000. The first plate 10 is sealingly connected to the box assembly 100 and covers the upper opening of the main installation area 102, so that the main installation area 102 is jointly enclosed by the first plate 10, the box assembly 100 and the second plate 20. The main installation area 102 and the control cabin 101 form independent spaces.

[0052] Referring to FIG. 5, at least one explosion-proof valve 30 is arranged on the frame 110. When the explosion-proof valve 30 is opened, the main installation area 102 is in communication with the outside. When thermal runaway occurs in the cell assembly 200, high-temperature flue gas can be discharged out of the battery pack 1000 through the explosion-proof valve 30. Since the main installation area 102 is jointly enclosed by the frame 110, the first cross beam 120, the first plate 10 and the second plate 20, the high-temperature flue gas cannot pass through the main installation area 102 and cannot enter the control cabin 101, thereby avoiding the situation that the control assembly 500 is in contact with the high-temperature flue gas and short-circuiting or internal electronic components are adhered and cannot be subjected to high-voltage electricity, and reducing the risk of thermal runaway.

[0053] Please refer to FIG. 2 and FIG. 3, since the main installation area 102 is a closed space, in order to facilitate the electrical connection between the control assembly 500 and the battery cell assembly 200, the first plate 10 is provided with a wire passing channel 11 for the conductive member 230 to pass through, and a wire passing sealing member 12 is arranged in the gap between the conductive member 230 and the wire passing channel 11, which not only ensures the sealing of the main installation area 102, but also enables the wiring through the gap between the upper cover 300 and the first plate 10, preventing the conductive member 230 from being adversely affected by high-temperature flue gas.

[0054] Therefore, according to one or more embodiments of the present application, the battery pack 1000, the box assembly 100, the first plate 10 and the second plate 20 isolate independent sealed spaces for installing the battery cell assembly 200, and the first plate 10 separates the control assembly 500 and the conductive member 230 for connecting the control assembly 500 and the battery cell assembly 200 from the battery cell assembly 200, thereby preventing the high-temperature flue gas generated by the thermal runaway of the battery cell from causing the internal electronic components of the control assembly 500 to adhere and the wiring harness to short circuit, achieving thermal and electrical separation, and improving the safety of the battery pack 1000.

[0055] The battery cell assembly 200 of the battery pack 1000 generally includes a large number of battery cells, and a plurality of battery cells are divided into a plurality of battery cell units. Taking a soft-pack battery cell as an example, a plurality of soft-pack battery cells are usually first assembled into a battery module, and a plurality of battery modules are connected in series and / or in parallel to form the battery cell assembly 200. For a square can battery cell, a certain number of square can battery cells are divided into a module, and a plurality of modules are connected in series and / or in parallel to form the battery cell assembly 200. Please refer to FIG. 2, in some embodiments, the battery cell assembly 200 includes a plurality of battery cell modules 210 electrically connected by a connecting copper bar 220, and the battery cell module 210 can be a battery module formed by a plurality of soft-pack battery cells or a module formed by a plurality of square can battery cells. It can be determined that the battery cell module 210 is a combination of two or more battery cells.

[0056] In order to prevent the thermal runaway of a single battery cell module 210 from spreading to other battery cell modules 210, in some embodiments, the box assembly 100 further includes at least one second cross beam 130 and at least one longitudinal beam 140 arranged in the frame 110, and the second cross beam 130 and the longitudinal beam 140 are both located in the main installation area 102 and divide the main installation area 102 into a plurality of battery compartments 103. The first plate 10 and the second plate 20 are both sealingly connected with the second cross beam 130 and the longitudinal beam 140, so as to form closed and independent spaces for each battery compartment 103, and a plurality of battery cell modules 210 are arranged one-to-one in a plurality of battery compartments 103. By forming closed and independent spaces for each battery compartment 103, the thermal runaway of a battery cell module 210 in a certain battery compartment 103 can be effectively blocked, and the high-temperature flue gas can be prevented from entering other battery compartments 103.

[0057] The number of the second cross beams 130 and the longitudinal beams 140 is determined according to the number of the battery cell modules 210. As shown in FIG. 1, the battery pack 1000 has four battery cell modules 210, and thus the battery pack 1000 has only one second cross beam 130 and one longitudinal beam 140. If the battery cell assembly 200 has six battery cell modules 210 arranged in a 2*3 matrix, two second cross beams 130 and one longitudinal beam 140 are needed.

[0058] The gap between the upper cover 300 and the first plate 10 is used for wiring. The upper cover 300 and the first plate 10 can be spaced apart to form a wiring space, or the wiring can be performed in the space formed by the reinforcing ribs 413 of the upper cover 300. The specific structure is not limited in the present application. In some embodiments, the upper cover 300 and the first plate 10 are spaced apart to enclose a wiring space for wiring. Since the first plate 10 only covers the upper opening of the main mounting area 102, the wiring space above the first plate 10 is in communication with the control cabin 101. The high-voltage copper bars, low-voltage wire harnesses and other conductive parts 230 can pass through the first plate 10, extend in the wiring space and electrically connect with the control assembly 500 in the control cabin 101. The wiring space is in communication with the control cabin 101, so that the high-voltage copper bars and the low-voltage wire harnesses can be normally connected to the control assembly 500. Since the wiring space and the control cabin 101 are both isolated from the main mounting area 102, the high-temperature flue gas in the main mounting area 102 cannot spread to the wiring space and the control cabin 101, thereby avoiding the failure of the internal electronic components of the control assembly 500 sticking together and unable to be connected to high-voltage electricity.

[0059] Please refer to FIG. 4. In some embodiments, since each battery cabin 103 is relatively closed and independent, the connecting copper bars 220 for electrically connecting the battery cell modules 210 also extend into the wiring space through the wire passing channel 11 and are sealed by the wire passing sealing member 12. The wire passing sealing member 12 can be sealing glue or a sealing ring. That is, the two connecting ends of the connecting copper bars 220 extend into different battery cabins 103 through the wire passing channel 11 and are electrically connected with two battery cell modules 210 respectively, and the main body part of the connecting copper bars 220 is located in the wiring space and crosses the second cross beam 130 or the longitudinal beam 140.

[0060] Referring to FIG. 2, in some embodiments, the control assembly 500 includes an electrically connected control device 510 and a power distribution device 520, the control device 510 can be a BMS (battery management system), and the power distribution device 520 can be a BDU (battery energy distribution unit, also known as a high-voltage power distribution box). The control device 510 and the power distribution device 520 are arranged side by side in the transverse direction (the axial direction of the cross beam). In some embodiments, the control device 510 adopts a master-slave topology framework, including one master control unit and two or more slave control units. Correspondingly, the conductive part 230 includes an output copper bar 231 for connecting the cell assembly 200 and the power distribution device 520, and a low-voltage sampling wire harness 232 for connecting the cell assembly 200 and the control device 510. That is, the low-voltage sampling wire harness 232 is electrically connected to each cell module 210 for collecting at least one of the voltage, current, and temperature of the cell module 210; and the output copper bar 231 is used to realize high-voltage electrical connection between the entire cell assembly 200 and the power distribution device 520.

[0061] In some embodiments, the battery pack 1000 is also provided with a thermal runaway sensor, which is also electrically connected to the control device 510. The thermal runaway sensor is usually installed in the battery compartment 103 and can obtain the concentration of particulate matter, temperature, air pressure, etc. in the battery compartment 103 to determine whether thermal runaway occurs in the battery compartment 103. Of course, the thermal runaway sensor can also detect other characteristic parameters, or be installed at other positions of the battery pack 1000. The thermal runaway sensor is a mature prior art, and the specific content can be referred to the related disclosure of the prior art, which is not limited in the present application. The control device 510 determines whether thermal runaway occurs in the battery pack 1000 according to the feedback signal of the thermal runaway sensor. When the thermal runaway sensor is usually installed in the battery compartment 103, the wire harness electrically connected between the thermal runaway sensor and the control device 510 also needs to extend into the wire routing space through the wire passage 11 and be sealed by the wire sealing element 12.

[0062] Referring to FIG. 3, in some embodiments, the wire passage 11 includes a plurality of first through holes 11a, a plurality of second through holes 11b, and a plurality of third through holes 11c. The output copper bar 231 extends into the first through hole 11a, the connection copper bar 220 extends into the second through hole 11b, and the low-voltage sampling wire harness 232 extends into the third through hole 11c. The positions of the first through hole 11a, the second through hole 11b, and the third through hole 11c are determined according to the positions of the high-voltage connection site 211 and the low-voltage sampling port 212 in the cell module 210, which are not limited in the present application.

[0063] Please refer to FIG. 6, which shows a structural schematic diagram of the battery cell module 210 in some embodiments. The high-voltage connection position 211 and the low-voltage sampling port 212 of the battery cell module 210 are distributed on different sides. When the battery cell module 210 is installed, the high-voltage connection position 211 is close to the frame 110, and the low-voltage sampling port 212 is close to the second cross beam 130 or the longitudinal beam 140. Correspondingly, the first through hole 11a and the plurality of second through holes 11b are distributed on the edge of the first plate 10; the third through hole 11c is distributed in the middle of the first plate 10, so as to realize the separation of high and low voltage. In some embodiments, the high-voltage connection position 211 and the low-voltage sampling port 212 are distributed on the same side of the battery cell module 210, and when the battery cell module 210 is installed, the high-voltage connection position 211 is close to the frame 110. Therefore, the first through hole 11a, the second through hole 11b and the third through hole 11c are all distributed on the edge of the first plate 10. By arranging the first through hole 11a, the second through hole 11b and the third through hole 11c on the edge and / or the middle of the first plate 10, the extension of the wire harness is located above the frame 110, the second cross beam 130 and the longitudinal beam 140 as much as possible. The height of the second cross beam 130 and the longitudinal beam 140 can be set to be lower than that of the frame 110, so that the corresponding position of the first plate 10 can form a sunken area to accommodate the wire harness.

[0064] Please refer to FIG. 3 and FIG. 4. In some embodiments, the first plate 10 is provided with a reinforcing rib 413 to improve the rigidity of the first plate 10. The wire passage 11 is arranged in the reinforcing rib 413. Since the structure and rigidity are good at the position of the reinforcing rib 413, the strength of the first plate 10 will not be greatly reduced by arranging the wire passage 11 in the reinforcing rib 413.

[0065] The sealing connection between the first plate 10 and the second plate 20 and the box assembly 100 can be realized by extrusion sealing, welding or applying sealant, which is not limited in the present application. Please refer to FIG. 1. In some embodiments, the first cross beam 120, the second cross beam 130, the longitudinal beam 140 and the edge cross beam of the frame 110 are all provided with a sealing gasket 50. The first plate 10, the box assembly 100 and the second plate 20 jointly compress the sealing gasket 50 to realize the mutual sealing between the battery compartments 103.

[0066] Since the upper cover 300 and the second plate 20 are respectively sealingly connected to the box assembly 100 and cover the upper and lower openings of the inner cavity of the frame 110, the whole battery pack 1000 is sealed. In some embodiments, the upper cover 300 and the second plate 20 are both connected to the box assembly 100 by FDS (flow-drill screw), and the connection is coated with sealant, meeting the IP67 sealing requirement of the battery pack 1000. At the same time, the upper cover 300 and the second plate 20 are both connected to the box assembly 100 by FDS, so that the upper cover 300 and the second plate 20 are stably connected to the box assembly 100 to bear the Z-direction load, and the upper cover 300 can apply a force to the first plate 10 for compressing the gasket 50.

[0067] The sealing connection between the first plate 10 and the box assembly 100 only needs to meet the requirement that the thermal runaway gas does not diffuse outward, and the sealing requirement is lower than the IP67 sealing requirement. Therefore, the first plate 10 and the box assembly 100 can be connected by FDS or screws, and the connection is coated with sealant to achieve sealing.

[0068] The upper cover 300 and the first plate 10 can be two independent parts or integrated. In some embodiments, the upper cover 300 and the first plate 10 are both made of metal and are welded together. The copper bar 220, the output copper bar 231, and the low-voltage sampling wire harness 232 are pre-set between the upper cover 300 and the first plate 10, and the interface part thereof extends out through the wire passage 11 of the first plate 10 to be electrically connected to the control assembly 500 and the cell assembly 200. After the upper cover 300 is connected to the box assembly 100, the sealing connection between the first plate 10 and the box assembly 100 is simultaneously achieved.

[0069] Please refer to FIGS. 5, 7 and 8. In some embodiments, the explosion-proof valve 30 is arranged on the outer wall of the frame 110, and at least one one-way valve 40 is arranged on the inner wall of the box assembly 100 corresponding to the position of the main mounting area 102. The frame 110 and the first cross beam 120 both have a gas exhaust passage 104 connected thereto, and the one-way valve 40 and the explosion-proof valve 30 are both connected to the gas exhaust passage 104. By arranging the one-way valve 40 and the explosion-proof valve 30, the high-temperature substances generated by thermal runaway can be released in a directional manner to the outside of the battery pack 1000, preventing other cells in the battery pack from being damaged again and reducing the loss caused by thermal runaway. Therefore, the battery pack 1000 provided by one or more embodiments of the present application has no requirements for the types and structures of the cells, and is suitable for square cell batteries with an explosion-proof valve 30, and is also suitable for soft-pack cells and cylindrical cells without an explosion-proof valve 30. Therefore, in some embodiments, the cells of the cell assembly 200 are soft-pack cells or cylindrical cells.

[0070] When thermal runaway occurs in the battery cell assembly 200, due to the one-way valve 40 corresponding to the position of the main mounting area 102, high-temperature smoke can enter the exhaust channel 104 of the frame 110 and the first cross beam 120 through the one-way valve 40, but the smoke in the exhaust channel 104 cannot flow back into the control cabin 101 and the main mounting area 102, and the smoke in the exhaust channel 104 is discharged out of the battery pack 1000 through the explosion-proof valve 30. By setting the exhaust channel 104, the flow path of the high-temperature smoke before being discharged is extended. In the first aspect, the exhaust channel 104 can store a certain volume of high-temperature smoke, which can play a buffering role and reduce the impact force of the gas flow discharged by the explosion-proof valve 30. In the second aspect, the temperature of the high-temperature smoke gradually decreases when it flows in the exhaust channel 104, which reduces the high-temperature hazard of the gas flow discharged by the explosion-proof valve 30. In the third aspect, when the high-temperature smoke flows in the exhaust channel 104, some particulate matter will settle downward, thereby reducing the content of conductive particulate matter in the gas flow discharged by the explosion-proof valve 30 and reducing the impact of the gas flow discharged by the explosion-proof valve 30 on other electrical devices of the vehicle.

[0071] When the frame 110 has multiple battery cabins 103 formed inside, the second cross beam 130 and / or the longitudinal beam 140 can also be hollow structures. That is, the second cross beam 130 and / or the longitudinal beam 140 also have exhaust channels 104, and the exhaust channels 104 of the second cross beam 130 and / or the longitudinal beam 140 are in communication with the exhaust channels 104 of the frame 110. In some embodiments, the frame 110, the first cross beam 120, the second cross beam 130, and the longitudinal beam 140 are all extruded aluminum profiles with cavities inside, which form the exhaust channels 104. The outer skin of the profiles at the connection between the frame 110, the first cross beam 120, the second cross beam 130, and the longitudinal beam 140 is removed, and the cavities are connected, and then welded, so that the cavities inside the frame 110, the first cross beam 120, the second cross beam 130, and the longitudinal beam 140 are all connected, as shown in FIG. 7.

[0072] Please refer to FIG. 9. In some embodiments, in order to reduce the impact of high-temperature smoke on the control cabin 101, two partitions 160 are respectively arranged in the two side longitudinal beams 111 of the frame 110, and the two partitions 160 correspond to the position of the first cross beam 120. The two partitions 160 block the cavities of the two side longitudinal beams 111, so that the cavities of the control cabin 101 corresponding part of the side longitudinal beam 111 are not in communication with the cavities of the main mounting area 102 corresponding part, and the high-temperature smoke cannot enter the position corresponding to the control cabin 101, thereby reducing the temperature rise rate inside the control cabin 101. Correspondingly, the explosion-proof valve 30 is arranged on the frame 110 corresponding to the main mounting area 102, as shown in FIG. 5, and no explosion-proof valve 30 is arranged on the frame 110 corresponding to the control cabin 101.

[0073] The partition plate 160 can be two flat plates extending outward from both ends of the first cross beam 120, which extend into the cavity of the edge longitudinal beam 111, thereby dividing the cavity of the edge longitudinal beam 111 into two parts. The partition plate 160 can also be a separately arranged plate member connected and fixed to the first cross beam 120 by means of adhesion, welding, fasteners, etc., to close the corresponding part of the control cabin 101.

[0074] When the frame 110 has multiple battery compartments 103 formed inside, each battery compartment 103 is correspondingly configured with one or more one-way valves 40. The one-way valves 40 can be arranged on the frame 110, the first cross beam 120, the second cross beam 130, or the longitudinal beam 140, and the specific installation position is not limited by the present application. Each battery compartment 103 can be correspondingly configured with one or more explosion-proof valves 30, which are arranged on the outer wall of the frame 110. When a certain battery module 210 of the cell assembly 200 experiences thermal runaway, the pressure in the battery compartment 103 where the battery module 210 is located rises, and the high-temperature substances generated by the thermal runaway enter the exhaust passage 104 through the one-way valve 40, first filling the entire exhaust passage 104. The gas in the exhaust passage 104 cannot be discharged back into the inside due to the restriction of the one-way valve 40. When the pressure in the exhaust passage 104 rises to the opening threshold of the explosion-proof valve 30, the smoke in the exhaust passage 104 is released to the outside through the explosion-proof valve 30.

[0075] Please refer to FIG. 8, in some embodiments, the one-way valve 40 and the explosion-proof valve 30 are arranged on the frame 110 and correspond to the plurality of battery compartments 103 one by one. The one-way valve 40 and the explosion-proof valve 30 corresponding to the same battery compartment 103 are distributed in staggered positions, on the one hand, to avoid the high-temperature smoke in the battery compartment 103 from being directly discharged from the explosion-proof valve 30 without buffering, which may adversely affect the external structure of the vehicle; on the other hand, the positions of the one-way valve 40 and the explosion-proof valve 30 are the weak positions of the frame 110, and by staggering the weak positions, the situation that the frame 110 is weak both inside and outside is avoided, and the structural strength of the frame 110 is ensured.

[0076] The first plate member 10 and the second plate member 20 can be separately arranged plate members in the battery pack 1000, or the battery pack 1000 can use its own parts as the first plate member 10 and the second plate member 20. Please refer to FIG. 1, FIG. 10, and FIG. 11, in some embodiments, the battery pack 1000 further includes a cooling assembly, which includes an upper liquid cooling plate 410 and a lower liquid cooling plate 420, the upper liquid cooling plate 410 and the lower liquid cooling plate 420 respectively constitute the first plate member 10 and the second plate member 20, and the cell assembly 200 is arranged on the lower liquid cooling plate 420. The double-layer liquid cooling can effectively improve the cooling rate and reduce the risk of thermal runaway.

[0077] The upper liquid cooling plate 410 and the lower liquid cooling plate 420 can be connected by a hose, and the battery pack 1000 only needs to be provided with one water inlet and one water outlet. In some embodiments, the upper liquid cooling plate 410 and the lower liquid cooling plate 420 are two independent cooling systems and are not connected. Two water inlets and two water outlets are provided on the frame 110. In some embodiments, an adapter can also be provided on the frame 110, and the inner cavity of the adapter realizes the shunt function of one inlet and two outlets.

[0078] Please refer to FIG. 1. In some embodiments, the battery pack 1000 further comprises a bottom guard plate 600, which is located at the lowermost part of the battery pack 1000. The bottom guard plate 600 is connected with the box assembly 100 and protects the lower liquid cooling plate 420. The bottom guard plate 600 and the box assembly 100 are sealed, and the bottom guard plate 600 and the lower liquid cooling plate 420 are also sealed.

[0079] Since the first plate 10 and the second plate 20 are both liquid cooling plates, in some embodiments, heat preservation foam is provided between the upper cover 300 and the upper liquid cooling plate 410 and between the bottom guard plate 600 and the lower liquid cooling plate 420. On the one hand, it plays a role in heat preservation and insulation, and on the other hand, it can support the upper cover 300, the upper liquid cooling plate 410, the bottom guard plate 600 and the lower liquid cooling plate 420, thereby improving the modal.

[0080] Please refer to FIG. 10 and FIG. 11, which show the structure of the front and back of the upper liquid cooling plate 410 in some embodiments. The upper liquid cooling plate 410 and the lower liquid cooling plate 420 both comprise a flat plate 411 and a flow channel plate 412. The flow channel plate 412 is punched with a flow channel 414 structure, and the flow channel plate 412 faces the cell assembly 200 during assembly. The flat plate 411 and the flow channel plate 412 are both provided with reinforcing ribs 413, which are distributed in a staggered manner with the flow channel 414. The flat plate 411 and the flow channel plate 412 are welded and fixed, and the welding lines are located at the edge parts of the flat plate 411 and the flow channel plate 412 and the positions of the reinforcing ribs 413. The wire passage 11 is provided in the reinforcing rib 413 of the upper liquid cooling plate 410 and does not occupy the space of the flow channel 414, as shown in FIG. 11.

[0081] The working principle of the battery pack 1000 of the present application when thermal runaway occurs will be described below taking the battery pack 1000 shown in FIG. 1 and FIG. 2 as an example:

[0082] The upper liquid cooling plate 410, the lower liquid cooling plate 420, the frame 110, the first cross beam 120, the second cross beam 130 and the longitudinal beam 140 isolate the inside of the battery pack 1000 into an independent sealed space, i.e. the battery cabin 103. The cell module 210 formed by a plurality of soft package cells is placed on the lower liquid cooling plate 420 and located in the above-mentioned battery cabin 103. The upper and lower double-layer liquid cooling can effectively improve the cooling rate and reduce the risk of thermal runaway.

[0083] When a certain soft package cell experiences thermal runaway, the pressure in the battery compartment 103 where the corresponding cell module 210 is located rises, and the high-temperature substances generated by thermal runaway enter the exhaust channel 104 of the crossbeam and the longitudinal beam and the frame 110 through the one-way valve 40, filling the entire exhaust channel 104. When the pressure in the exhaust channel 104 rises to the opening threshold of the explosion-proof valve 30, the plurality of explosion-proof valves 30 are opened at the same time, and the smoke in the exhaust channel 104 is released to the outside through the plurality of explosion-proof valves 30. The sealing of the upper liquid cooling plate 410 controls the smoke generated by thermal runaway in a single battery compartment 103, and the other battery compartments 103 are limited by the one-way valve 40, so that the gas in the exhaust channel 104 cannot be discharged into the inside, preventing the other cell modules 210 in the battery pack 1000 from being damaged again and reducing the loss caused by thermal runaway.

[0084] Meanwhile, the upper liquid cooling plate 410 separates the BDU and the BMS from the cells, and the connection of the high-voltage copper bars of the battery pack 1000 and the arrangement of the low-voltage sampling lines are all on the upper part of the upper liquid cooling plate 410. The connection of the connecting copper bars 220 and the low-voltage sampling line bundle 232 of adjacent battery compartments 103 is realized through the wire passage 11, and the wire passage 11 is sealed by the wire sealing element 12, so that the smoke generated by thermal runaway of the cells cannot spread to the BDU and the BMS, avoiding problems such as adhesion of the relays inside the BDU and failure to turn on and off high-voltage electricity.

[0085] The battery pack 1000 provided according to one or more embodiments of the present application has the following advantages:

[0086] 1) The box assembly 100, the first plate 10 and the second plate 20 isolate independent sealed spaces for installing the cell assembly 200, and the first plate 10 separates the control assembly 500 and the wire bundle from the cells, thereby preventing problems such as adhesion of electronic elements inside the control assembly 500 and short circuit of the wire bundle caused by smoke generated by thermal runaway of the cells, realizing thermal-electric separation and improving the safety of the battery pack 1000.

[0087] 2) The upper and lower two-layer liquid cooling plates can cool the cells from both sides, improving the cooling rate and reducing the risk of thermal runaway.

[0088] 3) The internal space of the side beam and the internal crossbeam and longitudinal beam 140 is used as the exhaust channel 104, and the one-way valve 40 and the explosion-proof valve 30 are used to realize directional eruption, block the spread of heat in the battery pack 1000, and improve the safety of the battery pack 1000. Moreover, there is no requirement for the type and structure of the cells, and it is suitable for all types of cells.

[0089] 4) Each explosion-proof valve 30 is in communication with the exhaust channel 104, and all the explosion-proof valves 30 can be opened at the same time when the cells are in thermal runaway, thereby rapidly reducing the internal pressure of the battery pack 1000 and reducing the risk of explosion of the battery pack 1000.

[0090] In the second aspect of the present application, a vehicle is provided, which comprises the battery pack 1000 of any of the embodiments of the first aspect. The vehicle specifically comprises a vehicle body and the battery pack 1000, and the battery pack 1000 is mounted on the vehicle body. The battery pack 1000 can be integrated into the chassis of the vehicle body, or mounted below the floor of the vehicle body.

[0091] In some embodiments, the two side longitudinal beams 111 of the frame 110 of the battery pack 1000 are connected to the rocker beams of the vehicle body by mounting bolts, and the mounting portions 112 of the side longitudinal beams 111 are connected to the rocker beams below the rocker beams. In some embodiments, the second transverse beam 130 of the battery pack 1000 is also provided with mounting bolts, and the second transverse beam 130 is connected to the floor assembly of the vehicle body by the mounting bolts. In order to avoid the impact on the mounting structure of the mounting portion 112 when the battery pack 1000 is in thermal runaway, the positions of the explosion-proof valves 30 should be staggered with the mounting holes of the mounting portion 112.

[0092] If the volume of the battery pack is large, in some embodiments, referring to FIGS. 1, 7 and 8, the battery pack 1000 further comprises a plurality of mounting brackets 150, which are distributed at the front and rear ends (X direction) of the frame 110, and the mounting brackets 150 are connected to the floor assembly of the vehicle body by mounting bolts. The connection of the battery pack 1000 and the vehicle body mainly bears pressure through the side mounting portions 112, and the mounting brackets 150 at the front and rear parts play an auxiliary role to share the pressure.

[0093] In the present application, unless otherwise explicitly specified and limited, the first feature is "on" or "under" the second feature, which can include that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, the first feature "on", "above" and "on top of" the second feature includes that the first feature is directly above and obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature "under", "below" and "underneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0094] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" indicate the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0095] In the present application, unless specifically defined otherwise and limited, the terms "connected", "fixed", and the like should be construed as being broad, for example, "fixed" can be fixed connection, or detachable connection, or integrated; can be mechanical connection, or electrical connection; can be direct connection, or indirect connection through intermediate medium; can be internal connection of two elements, or interaction relationship of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0096] In addition, in the present application, the description such as "first", "second" and the like is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically defined.

[0097] Although the embodiments of the present application have been shown and described, those skilled in the art can understand that various changes, modifications, replacements and variations can be made to these embodiments without departing from the principles and purposes of the present application, and the scope of the present application is defined by the claims and their equivalents.

Claims

1. A battery pack, comprising: a box assembly comprising a frame and a first cross beam arranged in the frame, an inner cavity of the frame being divided into a control cabin and a main installation area by the first cross beam, and at least one explosion-proof valve being arranged on the frame for connecting the main installation area with the outside; an upper cover sealingly connected to the box assembly and covering an upper opening of the inner cavity of the frame; a first plate and a second plate being arranged in a spaced manner below the upper cover; a cell assembly arranged in the main installation area; a control assembly arranged in the control cabin and electrically connected to the cell assembly through a conductive member; wherein the first plate is sealingly connected to the box assembly and covers an upper opening of the main installation area, the second plate is sealingly connected to the box assembly and covers a lower opening of the inner cavity of the frame, so that the main installation area and the control cabin form independent spaces; the first plate is provided with a wire passing channel for the conductive member to pass through, and a wire passing sealing member is arranged in the gap between the conductive member and the wire passing channel.

2. The battery pack of claim 1, wherein, The box assembly further comprises at least one second cross beam and at least one longitudinal beam arranged in the frame, and the second cross beam and the longitudinal beam are both located in the main installation area and divide the main installation area into a plurality of battery cabins; the first plate and the second plate are both sealingly connected to the second cross beam and the longitudinal beam, so that each battery cabin forms a closed and independent space; the cell assembly comprises a plurality of cell modules electrically connected through a connecting copper bar, and each of the plurality of cell modules is arranged in one of the plurality of battery cabins.

3. The battery pack of claim 2, wherein, The upper cover and the first plate are arranged in a spaced manner to enclose a wire routing space in communication with the control cabin; the connecting copper bar and the conductive member both extend into the wire routing space through the wire passing channel and are sealed by the wire passing sealing member.

4. The battery pack of claim 3, wherein, The control assembly comprises a control device and a power distribution device electrically connected, and the conductive member comprises an output copper bar for connecting the cell assembly and the power distribution device, and a low-voltage sampling wire harness for connecting the cell assembly and the control device; the wire passing channel comprises a plurality of first through holes, a plurality of second through holes and a plurality of third through holes arranged in a spaced manner; the output copper bar extends into the first through hole, the connecting copper bar extends into the second through hole, and the low-voltage sampling wire harness extends into the third through hole.

5. The battery pack of claim 4, wherein, The first through holes and the second through holes are arranged at the edges of the first plate; the third through holes are arranged at the edges and / or the middle of the first plate; the first plate is provided with a reinforcing rib, and the wire passing channel is arranged in the reinforcing rib.

6. The battery pack of any one of claims 2-5, wherein, Sealing gaskets are arranged on the first cross beam, the second cross beam, the longitudinal beam and the edge cross beam of the frame, and the sealing gaskets are compressed by the first plate, the box assembly and the second plate.

7. The battery pack of claim 6, wherein, The upper cover and the second plate are both FDS connected to the box assembly, and the connection is coated with sealing glue; the upper cover applies a force to the first plate for compressing the sealing gaskets. The first plate member is connected with the box assembly FDS or connected through screws, and the connection is coated with sealant; or the upper cover and the first plate member are welded as a whole.

8. The battery pack of any one of claims 2-5, wherein, The inner wall of the box assembly is provided with at least one one-way valve corresponding to the position of the main mounting area, the explosion-proof valve is arranged on the outer wall of the frame, the frame and the first cross beam both have a connected exhaust passage, and the one-way valve and the explosion-proof valve both communicate with the exhaust passage.

9. The battery pack of claim 8, wherein, The second cross beam and / or the longitudinal beam also have the exhaust passage, and the exhaust passage of the second cross beam and / or the longitudinal beam communicates with the exhaust passage of the frame.

10. The battery pack of claim 8, wherein, The one-way valve and the explosion-proof valve are arranged on the frame and correspond to the battery compartments one by one; the one-way valve and the explosion-proof valve are distributed in staggered positions.

11. The battery pack of any one of claims 1-5, wherein, The battery pack further comprises a cooling assembly, the cooling assembly comprises an upper liquid cooling plate and a lower liquid cooling plate, the upper liquid cooling plate and the lower liquid cooling plate respectively constitute the first plate member and the second plate member; and the battery cell assembly is arranged on the lower liquid cooling plate.

12. The battery pack of claim 11, wherein, The upper liquid cooling plate and the lower liquid cooling plate both comprise a plane plate and a flow channel plate, the flow channel plate faces the battery cell assembly; the plane plate and the flow channel plate are both provided with reinforcing ribs, the edge portions of the plane plate and the flow channel plate and the positions where the reinforcing ribs are located are welded; and the wire passing channel is arranged in the reinforcing ribs.

13. The battery pack of any one of claims 1-5, wherein, The battery cell of the battery cell assembly is a soft package battery cell or a cylindrical battery cell.

14. A vehicle comprising the battery pack according to any one of claims 1-13.

Images