WO2022213639A1

WO2022213639A1 - Power battery assembly and vehicle

Info

Publication number: WO2022213639A1
Application number: PCT/CN2021/135936
Authority: WO
Inventors: 卢军; 孙焕丽; 许立超; 乔延涛; 荣常如; 孙士杰; 刘鹏; 姜云峰
Original assignee: 中国第一汽车股份有限公司
Priority date: 2021-04-08
Filing date: 2021-12-07
Publication date: 2022-10-13
Also published as: CN113113713A; CN113113713B

Abstract

A power battery assembly and a vehicle. The power battery assembly comprises a battery casing, two battery packs (2), a high-voltage wire circuit (3) and a low-voltage wire circuit (4). The battery casing comprises a box body (1), wherein a longitudinal beam (11) is arranged in the box body (1), and the longitudinal beam (11) divides the box body (1) into two mounting grooves (12); each battery pack (2) comprises a plurality of battery modules (21), and the two battery packs (2) are respectively arranged in the two mounting grooves (12); positive and negative electrodes of the plurality of battery modules (21) are facing side walls of the box body (1); the high-voltage wire circuit (3) comprises high-voltage copper bars (31), and the high-voltage copper bars (31) are arranged between the two battery packs (2) and a gap between each battery pack (2) and the side wall of the box body (1); and the low-voltage wire circuit (4) comprises a low-voltage wire harness (43) and a control sub-board (42), and the control sub-board (42) is arranged between the two battery packs (2).

Description

Power battery assembly and vehicle

This application claims the priority of a Chinese patent application with application number 202110379145.7 filed with the China Patent Office on April 8, 2021, the entire contents of which are incorporated herein by reference.

technical field

The present application relates to the technical field of power batteries, for example, to a power battery assembly and a vehicle.

Background technique

The development prospect of new energy vehicles is very broad. New energy vehicles have the characteristics of high energy efficiency, zero emissions, no pollution, high specific energy, low noise and high reliability. As the energy storage component of the new energy battery vehicle, the power battery system can ensure the driving of the whole vehicle, the electricity demand of high and low voltage components, the recovery of braking energy, and the energy regulation of the hybrid engine system.

However, the safety of the power battery assembly has always been the key to quality. With the rapid development of the demand for high-energy and high-power battery assemblies, a series of safety problems have been brought about by the battery assembly. When the power battery fails, it is easy to catch fire and burn, and quickly spread to the entire battery pack. The accumulation of high-pressure gas generated by the power battery poses a risk of explosion, which seriously threatens the lives of occupants.

SUMMARY OF THE INVENTION

The present application provides a power battery assembly and a vehicle, which can prevent the flame from rapidly spreading to the battery module on the opposite side of the battery module when the battery module fails, and prevent the high-pressure gas generated by combustion from being rapidly discharged from the battery pack.

A power battery assembly is provided, including:

A battery case, the battery case includes a box body and a cover plate buckled on the box body, a longitudinal beam is arranged in the box body, the longitudinal beam penetrates the box body and divides the box body into two parts an installation slot, and a side wall of the box body close to one end of the longitudinal beam is provided with a accommodating cavity;

Two battery packs, each battery pack includes a plurality of battery modules, the two battery packs are respectively arranged in the two installation slots, and the positive and negative poles of the plurality of battery modules are facing the box body the side wall;

A high-voltage line, the high-voltage line includes a high-voltage copper bar, and the high-voltage copper bar is arranged in the gap between the two battery packs and between the battery pack and the side wall of the box, the high-voltage copper bar electrically connected with the positive and negative electrodes of the battery module;

A low-voltage line, the low-voltage line includes a low-voltage wiring harness, a control main board and a control sub-board, the low-voltage wiring harness is arranged between the two battery packs, and the low-voltage wiring harness is electrically connected to the control main board and the control sub-board , the control sub-board is arranged between the two battery packs, and the control main board is arranged in the accommodating cavity.

The power battery assembly can also include:

an active fuse, the active fuse is arranged at the midpoint of the high-voltage line, and the midpoint is the midpoint of the voltage in the entire high-voltage line, and the active fuse is electrically connected to the control motherboard;

An intelligent power distribution box, the intelligent power distribution box is connected in series with the high-voltage copper bars, and the intelligent power distribution box is communicatively connected with the control main board.

The high-voltage copper bar may include a copper bar and a cladding material covering the outside of the copper bar.

The power battery assembly may further include a cooling mechanism, and the cooling mechanism may include:

a cooling pipe, the cooling pipe is arranged between the battery pack and the side wall of the box;

A liquid cooling plate, the liquid cooling plate is arranged on the bottom plate of the box body, and the liquid cooling plate is communicated with the cooling pipe.

The distance between the cooling pipe and the high-voltage copper bar located between the battery pack and the side wall of the box may be 5mm-10mm.

Each installation slot may be provided with a plurality of beams, the plurality of beams divide the installation slot into a plurality of spaces, the battery module can be placed in each space, and the height of the beam is not lower than the height of the The height of the battery module.

The inside of the box body may be provided with an insulating layer.

The power battery assembly may further include an explosion-proof valve, the explosion-proof valve is disposed on the side wall of the box on the opposite side of the accommodating cavity, and the explosion-proof valve is close to an end of the longitudinal beam away from the accommodating cavity.

The power battery assembly can also include:

a plurality of pressure sensors, each battery module is provided with at least one pressure sensor;

a smoke sensor, the smoke sensor is arranged in the box;

a voltage monitor connected in parallel with the high voltage line.

A plurality of the control sub-boards may be provided, and the plurality of control sub-boards are respectively electrically connected to the pressure sensor, the smoke sensor and the voltage monitor.

A vehicle is also provided, including the power battery assembly.

Description of drawings

1 is a schematic structural diagram of a power battery assembly provided by the present application;

Fig. 2 is the structural representation of the box provided by the application;

3 is a schematic structural diagram of a control sub-board provided by the present application;

FIG. 4 is a schematic structural diagram of a high-voltage copper bar provided by the present application.

In the picture:

1. Box body; 2. Battery pack; 3. High-voltage line; 4. Low-voltage line; 5. Active fuse; 6. Cooling mechanism; 7. Intelligent power distribution box; 8. Pressure sensor;

11. Longitudinal beam; 12. Installation slot; 13. Receiving cavity; 14. Beam; 21. Battery module; 31. High-voltage copper bar; 41. Control main board; 42. Control sub-board; 43. Low-voltage wiring harness; 61. Cooling tube; 62, liquid cooling plate;

311, copper bar; 312, cladding material.

Detailed ways

Embodiments of the present application are described below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary, and are intended to be used to explain the present application, but should not be construed as a limitation to the present application.

In the description of this application, the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" etc. refer to the orientation or position The relationship is based on 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 device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore It should not be construed as a limitation on this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed to indicate or imply relative importance. Therein, the terms "first position" and "second position" are two different positions.

Unless otherwise specified and limited, the terms "installed", "connected", "connected" and "fixed" should be understood in a broad sense, for example, it may be a fixed connection or a detachable connection; it may be a mechanical connection or a Electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between the two elements. The meanings of the above terms in this application can be understood according to actual situations.

Unless otherwise specified and limited, a first feature "on" or "under" a second feature may include the first feature and the second feature in direct contact, or the first feature and the second feature are not in direct contact but Contact through additional features between them. Also, the first feature being "above", "over" and "above" the second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is level higher than the second feature. The first feature is "below", "below" and "below" the second feature includes the first feature being directly below and diagonally below the second feature, or simply means that the first feature has a lower level than the second feature.

The technical solutions of the present application will be described below with reference to the accompanying drawings and through embodiments.

This embodiment provides a power battery assembly. As shown in FIGS. 1-3 , the power battery assembly includes a battery casing, two battery packs 2 , a high-voltage line 3 and a low-voltage line 4 . The battery housing includes a box body 1 and a cover plate buckled on the box body 1. A longitudinal beam 11 is arranged in the box body 1. The longitudinal beam 11 penetrates the box body 1 and divides the box body 1 into two installation slots 12. The box body 1 A side wall near one end of the longitudinal beam 11 is provided with a receiving cavity 13 . The battery pack 2 includes a plurality of battery modules 21 , and the two battery packs 2 are respectively disposed in the two installation slots 12 . The high-voltage circuit 3 includes a high-voltage copper bar 31 . The high-voltage copper bar 31 is arranged between the two battery packs 2 and the gap between the battery pack 2 and the side wall of the box 1 . pole electrical connection. The low-voltage circuit 4 includes a low-voltage wiring harness 43, a control main board 41 and a control sub-board 42. The low-voltage wiring harness 43 is arranged between the two battery packs 2, and the low-voltage wiring harness 43 is electrically connected to the control main board 41 and the control sub-board 42. The control sub-board 42 is provided with Between the two battery packs 2 , the control main board 41 is disposed in the accommodating cavity 13 .

The longitudinal beam 11 of the box body 1 improves the structural strength of the box body 1, and divides the box body 1 into two installation slots 12, and the two battery packs 2 are respectively installed in the two installation slots 12, in the middle of the two battery packs 2 That is, the position of the longitudinal beam 11 forms a channel, and the control sub-board 42 is arranged between the two battery packs 2, which can shorten the distance of the sampling harness between the modules, speed up the response, and monitor the battery safety status more accurately and in a timely manner. It can also effectively block the high temperature and high pressure gas and electrolyte sprayed by the thermal runaway module, which can ensure that the battery module 21 can only be thermally runaway alone, and cannot quickly spread to the opposite module. Since the positive and negative electrodes of the battery modules 21 are facing the side wall of the box 1, the high-voltage copper bars 31 between the two battery packs 2 do not need to be interrupted or branched to connect the electrodes, that is, the two battery packs 2 The high-voltage copper bar 31 between them is a complete through structure. When the thermal runaway of the battery module 21 produces a large amount of gas, these gases will gather together to form a great pressure, and since the high-voltage copper bar 31 between the two battery packs 2 runs through from front to back, it can play a good role in guiding. The flow action prevents local high pressure and reduces the risk of explosion.

The power battery assembly determines the number of battery modules 21 required according to the design of the vehicle, and then the length of the longitudinal beam 11 in the direction can be changed according to the number of battery modules 21 to achieve various arrangements of the number of battery modules 21 , such as

arrangement

4, 6, 8, 10, 12 and 14 battery modules 21. Similarly, the power battery can also change the length perpendicular to the direction of the longitudinal beam 11 according to the length of the battery module 21 to adapt to the battery modules 21 of different lengths, such as the battery modules 21 of 355mm, 390mm and 590mm and the battery modules 21 of 600mm and 900mm. The size of the blade battery module 21.

The power battery assembly may also include an active fuse 5 and an intelligent power distribution box 7 . The active fuse 5 is arranged at the midpoint of the high-voltage line 3, and is also the midpoint of the voltage in the entire high-voltage line. The active fuse 5 is electrically connected to the control main board 41, and the intelligent power distribution box 7 is connected in series with the high-voltage copper bar 31 for intelligent power distribution. The box 7 is connected in communication with the control main board 41 .

The intelligent power distribution box 7 can monitor the value of the current in the circuit in the high-voltage line 3. When the battery module 21 is thermally out of control, a short circuit occurs, and the current in the circuit increases significantly. The intelligent power distribution box 7 detects the abnormality and sends the information to the control. The main board 41 controls the main board 41 to control the active fuse 5 to blow. When the battery is thermally out of control, the battery module 21 will explode and burn violently. At this time, the thermal runaway module and the lower box 1 are basically in a short-circuit state, and high-voltage arcing is very likely to occur. The active fuse 5 is located in the middle of the high-voltage circuit. Once the active fuse 5 is cut off to disconnect the entire high-voltage circuit, the voltage at each end is only half of the total voltage, which avoids high-voltage arcing caused by thermal runaway and effectively delays Battery thermal runaway.

The positive and negative poles of the battery modules 21 are facing the side wall of the box 1, that is, the outside of the two battery modules 21, in order to arrange the high-voltage output parts around the two battery packs 2, in order to make the power battery total. In the event of thermal runaway, the high-voltage line 3 and the low-voltage line 4 do not affect each other, and the active fuse 5 is arranged at a position close to the longitudinal beam 11 . When the active fuse 5 is blown, the high-voltage copper bar 31 between the two battery packs 2 is disconnected, so that the high-voltage line 3 of the power battery assembly is located around the two battery packs 2, and the low-voltage line 4 is located in the two battery packs 2. There is no mutual interference between the battery packs 2, and the thermal runaway occurring at the high-voltage output part will not spread the burning flame to the low-voltage place, effectively delaying the thermal runaway of the battery.

As shown in FIG. 4 , the high-voltage copper bar 31 includes a copper bar 311 and a cladding material 312 covering the outside of the copper bar 311 . The coating material 312 is a non-metallic material with high temperature resistance and insulation, including mica, high temperature ceramics, special aerogel, etc. The coating material 312 can guarantee the high temperature and high pressure gas and electrolyte when the battery module 21 thermally runs out of control. The high-voltage copper bar 31 can maintain the structural integrity so as to effectively block the gas and electrolyte and conduct the gas flow.

The power battery assembly may further include a cooling mechanism 6 , and the cooling mechanism 6 includes a cooling pipe 61 and a liquid cooling plate 62 . The cooling pipe 61 is disposed between the battery pack 2 and the side wall of the case 1 . The liquid cooling plate 62 is arranged on the bottom plate of the box body 1 , and the liquid cooling plate 62 communicates with the cooling pipe 61 .

When the battery module 21 is installed in the installation groove 12, it is attached to the liquid cooling plate 62 at the bottom of the box, and the heat exchange area is large. The liquid cooling plate 62 is provided with a plurality of channels inside, and the cooling liquid flows through the channels that can absorb the battery module 21. The heat cools the battery module 21 . The cooling pipe 61 circulates the cooling liquid, and transports the heat absorbed from the battery module 21 to the outside for discharge.

The distance between the cooling pipe 61 and the high-voltage copper bar 31 located between the battery pack 2 and the side wall of the case 1 is 5 mm-10 mm. The high-voltage positive and negative electrodes of the battery module 21 are very prone to thermal runaway due to high current charging and discharging. Once thermal runaway occurs here, the flame will quickly spray to the water pipe, destroying the water pipe. The coolant in the water pipe is a non-flammable liquid. The thermal runaway flame at the positive and negative poles of the battery module 21 can be quickly extinguished, effectively delaying the thermal runaway.

In order to improve the strength of the box body 1, each installation slot 12 is provided with a plurality of beams 14, and the plurality of beams 14 divide the installation slot 12 into a plurality of spaces, each space can place the battery module 21, and the beam 14 is not low in the battery module 21 . The height of the beam 14 is higher than that of the battery modules 21, which can separate the battery modules 21. Once the thermal runaway of the modules in one area occurs, it can only be limited to the inside of the area in a short time, and cannot spread rapidly.

In order to block the heat generated by the thermal runaway of the battery modules 21 in each space and prevent the adjacent battery modules 21 from running out of control caused by high temperature, an insulating and heat insulation layer is provided inside the box 1 . The insulating layer is a high-temperature-resistant insulating material with a thermal conductivity of ≤0.02W/(m*k). The high-temperature-resistant insulating material is sprayed into the interior of the box 1, which can not only delay the spread of thermal runaway, but also effectively act as a driving force. The battery assembly provides a heat preservation function to save power consumption in winter.

The power battery assembly may also include an explosion-proof valve. The explosion-proof valve is disposed on the side wall of the box body 1 on the opposite side of the accommodating cavity 13 , and the explosion-proof valve is close to the end of the longitudinal beam 11 away from the accommodating cavity 13 . The explosion-proof valve can discharge the gas to the outside of the power battery assembly when a large amount of high-temperature and high-pressure gas is generated by the thermal runaway of the battery module 21. Since the high-pressure copper bar 31 has a guiding effect on the gas, the explosion-proof valve is arranged on the longitudinal beam 11 away from the accommodating cavity. One end of 13 can directly discharge the gas guided by the high-pressure copper bar 31, thereby shortening the flow path of the high-pressure gas.

In order to monitor the thermal runaway of the power battery assembly from multiple dimensions, the power battery assembly further includes a plurality of pressure sensors 8, smoke sensors and voltage monitors. Each battery module 21 is provided with at least one pressure sensor 8 . The smoke sensor is arranged in the box body 1 . The voltage monitor is connected in parallel with the high voltage line 3 .

When a battery module 21 is thermally out of control, a large amount of high temperature and high pressure gas is generated, the casing of the battery module 21 bulges or the pressure inside the power battery assembly changes rapidly, the pressure sensor 8 is triggered and alarms. When the battery module 21 is thermally out of control, a large amount of gas is generated to trigger the smoke sensor. Or a failure of a battery module 21 causes the voltage to drop rapidly, triggering the voltage monitor. A variety of sensors are used together to monitor various phenomena when thermal runaway occurs in the battery module 21 , so that the control main board 41 can effectively identify the thermal runaway of the battery and proactively prevent danger.

In order to enable the control main board 41 to identify the signals of various sensors, there are multiple control sub-boards 42, and the plurality of control sub-boards 42 are respectively electrically connected to the pressure sensor 8, the smoke sensor and the voltage monitor. Each sensor is electrically connected to at least one control sub-board 42 , which enables the control main board 41 to effectively identify the sensor signals, and comprehensively analyze the state of the power battery assembly, so as to discover hidden dangers in the power battery assembly in time and take the initiative to prevent them.

In order to shorten the product development cycle and reduce the research and development cost, the smoke sensor is integrated into the all-in-one controller, and the all-in-one controller also integrates the water temperature sensor and flow regulator of the coolant, which can monitor the temperature of the coolant and Flow regulation.

This embodiment also provides a vehicle, the vehicle includes the above-mentioned power battery assembly, which effectively delays the thermal runaway of the battery, and can realize a lightweight design on the basis of ensuring the safety of the vehicle, especially the power battery assembly, which not only ensures the safety of the occupants, And can save energy.

The application provides a power battery assembly and a vehicle. In the power battery assembly, battery packs composed of a plurality of battery modules are respectively arranged in the installation slots on both sides of the longitudinal beam, and the high-voltage copper bar and the control sub-board are arranged between the two battery packs, which can effectively block the The high temperature and high pressure gas and electrolyte sprayed by the thermal runaway module ensure that the battery module can only thermally runaway alone, and cannot quickly spread to the opposite module. In addition, a large amount of gas generated by the thermally runaway battery pack will gather together, which will form a great pressure, and the high-voltage copper bar in the middle can play a good role in diversion, so that local high pressure will not be generated inside the power battery assembly, greatly reducing the pressure. Reduced risk of explosion.

Claims

A power battery assembly, comprising:

A battery case, the battery case includes a box body (1) and a cover plate buckled on the box body (1), a longitudinal beam (11) is arranged in the box body (1), and the longitudinal beam (11) Passing through the box body (1) and dividing the box body (1) into two installation grooves (12), the box body (1) is disposed close to one side wall of one end of the longitudinal beam (11) There is an accommodating cavity (13);

Two battery packs (2), each battery pack (2) includes a plurality of battery modules (21), the two battery packs (2) are respectively arranged in the two installation slots (12), the The positive and negative electrodes of the plurality of battery modules (21) are all facing the side wall of the box body (1);

A high-voltage line (3), the high-voltage line (3) includes a high-voltage copper bar (31), and the high-voltage copper bar (31) is arranged between the two battery packs (2) and each battery pack ( 2) the gap with the side wall of the box body (1), the high-voltage copper bar (31) is electrically connected to the positive and negative electrodes of the plurality of battery modules (21);

A low-voltage line (4), the low-voltage line (4) includes a low-voltage wiring harness, a control main board (41) and a control sub-board (42), the low-voltage wiring harness is arranged between the two battery packs (2), the The low-voltage wiring harness is electrically connected to the control main board (41) and the control sub-board (42), the control sub-board (42) is arranged between the two battery packs (2), and the control main board (41) ) is arranged in the accommodating cavity (13).
The power battery assembly according to claim 1, further comprising:

an active fuse (5), the active fuse (5) is arranged at the midpoint of the high-voltage line (3), and the midpoint is the midpoint of the voltage in the entire high-voltage line (3), the The active fuse (5) is electrically connected to the control mainboard (41);

An intelligent power distribution box (7), the intelligent power distribution box (7) is connected in series with the high-voltage copper bars (31), and the intelligent power distribution box (7) is connected in communication with the control main board (41).
The power battery assembly according to claim 1, wherein the high-voltage copper bar (31) comprises a copper bar (311) and a cladding material (312) covering the outside of the copper bar (311).
The power battery assembly according to claim 1, further comprising a cooling mechanism (6), the cooling mechanism (6) comprising:

a cooling pipe (61), the cooling pipe (61) is arranged between each of the battery packs (2) and the side wall of the box body (1);

A liquid cooling plate (62), the liquid cooling plate (62) is disposed on the bottom plate of the box body (1), and the liquid cooling plate (62) communicates with the cooling pipe (61).
The power battery assembly according to claim 4, wherein the cooling pipe (61) is connected to a high-voltage copper bar ( 31) The distance is 5mm-10mm.
The power battery assembly according to claim 1, wherein each installation groove (12) is provided with a plurality of beams (14), and the plurality of beams (14) separates each installation groove (12) A plurality of spaces are formed, and the plurality of battery modules (21) can be placed in each space, and the height of the beam (14) is not lower than the height of the plurality of battery modules (21).
The power battery assembly according to claim 1, wherein an insulating layer is provided inside the box (1).
The power battery assembly according to claim 1, further comprising an explosion-proof valve, the explosion-proof valve is arranged on the side wall of the box body (1) on the opposite side of the accommodating cavity (13), and the explosion-proof valve is close to One end of the longitudinal beam (11) away from the accommodating cavity (13).
The power battery assembly according to any one of claims 1-8, further comprising:

a plurality of pressure sensors (8), each battery module (21) is provided with at least one pressure sensor (8);

a smoke sensor, which is arranged in the box (1);

A voltage monitor, which is connected in parallel with the high-voltage line (3).
The power battery assembly according to claim 9, wherein a plurality of the control sub-boards (42) are provided, and the plurality of control sub-boards (42) are respectively connected with the plurality of pressure sensors (8), the smoke The sensor and the voltage monitor are electrically connected.
A vehicle comprising the power battery assembly of any one of claims 1-10.