WO2022056722A1

WO2022056722A1 - Battery cell, battery pack, system, and electric vehicle

Info

Publication number: WO2022056722A1
Application number: PCT/CN2020/115571
Authority: WO
Inventors: 钟正; 陈诚
Original assignee: 华为数字能源技术有限公司
Priority date: 2020-09-16
Filing date: 2020-09-16
Publication date: 2022-03-24
Also published as: CN115668612A

Abstract

Disclosed by the present application are a battery cell, battery pack, system, and electric vehicle, relating to the technical field of batteries. The battery cell comprises a battery-cell core body and a battery-cell outer housing, said battery-cell core body being arranged inside said battery-cell outer housing, the battery-cell outer housing comprising: a positive electrode post, a negative electrode post, and a shatter-proof valve; the positive electrode post and negative electrode post are located on the upper surface of the battery-cell outer housing; the shatter-proof valve is located on the side of said battery-cell outer housing; the shatter-proof valve is used for opening when the internal pressure of said battery-cell outer housing is greater than or equal to an open-valve pressure threshold. The shatter-proof valve of the battery cell is arranged on the side face of the battery-cell outer housing, and is not on the same surface as the positive and negative electrode posts; when the shatter-proof valve is open, an electrolyte vapor is brought out and part of the electrolyte is directed to the side face of the battery-cell outer housing, therefore there is no contact with the power connection rows and sampling wire harnesses, avoiding short-circuit firing and enhancing security.

Description

A battery cell, battery pack, system and electric vehicle

technical field

The present application relates to the field of battery technology, and in particular, to a battery cell, a battery pack, a system and an electric vehicle.

Background technique

Lithium-ion battery is a kind of rechargeable battery. Because of its advantages of small size, light weight and long cycle life, it is widely used in communication base stations, data centers, energy storage power stations and electric vehicles.

In practical applications, the cells of lithium-ion batteries contain electrolyte and active lithium, which have the characteristics of high activity and flammability, and are prone to fire accidents. Therefore, in order to prevent the cells of lithium-ion batteries from deflagrating and igniting under abnormal conditions such as overcharge and short circuit, an explosion-proof valve is designed on the cover plate of the cell shell. When the internal pressure of the cell shell is large, the valve is opened to release pressure, thereby Prevent battery explosion.

However, the current explosion-proof valve and the positive and negative poles of the cell are set on the cover plate together, and the positive and negative poles are connected to the power connection row and the sampling harness, and the electrolyte vapor brought out when the explosion-proof valve is opened is in contact with part of the electrolyte Short-circuit ignition may occur when the power connection bar and the sampling harness are connected, which may easily cause the battery to burn, posing a safety hazard.

SUMMARY OF THE INVENTION

The present application provides a battery cell, a battery pack, a system and an electric vehicle, which prevent the electrolyte brought out when the explosion-proof valve is opened from contacting the power connection row and the sampling wire harness, thereby improving safety.

In a first aspect, the present application provides a cell, which includes a cell body and a cell shell, the cell core body is disposed inside the cell shell, and the cell shell includes a positive pole, a negative pole and an explosion-proof valve. The positive pole and the negative pole are located on the upper surface of the cell shell; the explosion-proof valve is located on the side of the cell shell; the explosion-proof valve is used to open when the internal pressure of the cell shell is greater than or equal to the valve opening pressure threshold.

The explosion-proof valve of the battery cell provided by this application is arranged on the side of the battery core shell, not on the same surface as the positive and negative poles. When the explosion-proof valve is opened, the electrolyte vapor and part of the electrolyte solution are brought out and lead to the battery core shell. side, so it will not touch the power connection bar and sampling wire harness, avoid short-circuit and ignition, and improve safety.

With reference to the first aspect, in a first possible implementation manner, the cell casing includes a cover plate and a casing. The positive and negative poles are located on the cover plate. The side of the casing is the side of the cell shell, that is, the explosion-proof valve is arranged on the side of the casing, not on the same surface as the positive and negative poles.

With reference to the first aspect, in a second possible implementation manner, the cell casing includes a cover plate and a casing, and the cover plate includes a first surface and a second surface. The second surface is perpendicular to the first surface and is connected with the side of the first surface, and the explosion-proof valve is located on the second surface. The first surface is the upper surface of the cell shell, and the second surface is connected to the side surface of the shell.

The cover plate of this implementation includes two surfaces that are perpendicular to each other, the positive and negative poles are arranged on the first surface, and the explosion-proof valve is arranged on the second surface. When the explosion-proof valve is opened, the entrained electrolyte vapor and part of the electrolyte are directed to the second surface, so they will not contact the power connection bar and sampling harness connected to the positive and negative poles of the first surface.

With reference to the first aspect, in a third possible implementation manner, the outer casing of the battery cell is a cuboid, a cube or a cylinder.

In a second aspect, the present application further provides a battery pack, the battery pack includes at least one battery cell described in the above implementation manner. The explosion-proof valve of the battery cell is set on the side of the battery cell shell, not on the same surface as the positive and negative poles. When the explosion-proof valve is opened, the electrolyte vapor and part of the electrolyte solution are brought out and directed to the side of the battery core shell. Therefore, It will not touch the power connection bar and sampling wire harness, avoid short-circuit and ignition, and improve the safety of the battery pack.

With reference to the second aspect, in a first possible implementation manner, the battery pack further includes a liquid guiding groove. The explosion-proof valve of the at least one cell shell faces the tank body of the liquid guiding tank. The liquid guide groove is used to provide a directional flow channel for the gas and electrolyte discharged from the explosion-proof valve when the explosion-proof valve is opened.

The liquid guiding tank also has the function of collecting the electrolyte vapor and part of the electrolyte discharged from the explosion-proof valve.

With reference to the second aspect, in a second possible implementation manner, a temperature sensor is provided in the liquid guiding groove. The temperature sensor is used to detect the temperature in the liquid guiding tank and send the detection result to the battery management system BMS of the battery pack.

When the BMS uses the detection result to determine that the temperature rises to exceed the preset threshold, it determines that the current explosion-proof valve has been opened.

With reference to the second aspect, in a third possible implementation manner, a gas sensor is provided in the liquid guiding groove. The gas sensor is used to detect whether a preset type of gas is present in the liquid guiding tank, and send the detection result to the battery management system BMS of the battery pack. The type of gas sensor can be determined according to the type of gas generated when the cell is abnormal. For example, when carbon monoxide (CO) gas is generated when the battery cell is abnormal, a gas sensor for detecting carbon monoxide can be used.

When the BMS uses the detection result of the gas sensor to determine that a preset type of gas appears in the liquid guiding tank, it is determined that the current explosion-proof valve has been opened,

With reference to the second aspect, in a fourth possible implementation manner, a fire protection module is provided in the liquid guiding tank. When the BMS determines that the explosion-proof valve is open using the detection result, it sends a fire-fighting command to the fire-fighting module. The fire-fighting module is used to trigger the fire-fighting action after obtaining the fire-fighting command, that is, to cool the battery pack and put out the fire.

With reference to the second aspect, in a fifth possible implementation manner, the battery pack further includes a power protection cover. The power protection cover covers the positive pole and the negative pole of the at least one battery cell, so as to further prevent the gas, electrolyte vapor and electrolyte discharged from the explosion-proof valve from contacting the positive pole, the negative pole, the power connection row and the sampling wire harness. Safety of battery packs.

In a third aspect, the present application further provides a power supply system, where the power supply system includes the battery pack described in any one of the above implementation manners. The power supply system is used to power the connected loads. The power supply system can be applied to communication base stations, data centers, energy storage power stations, electric vehicles and other fields. In some embodiments, the type of battery pack may be a lithium ion battery pack.

In a fourth aspect, the present application further provides an electric vehicle, which includes an electric motor and the battery pack provided by the above implementation manner. Among them, the battery pack is used to provide electrical energy for the electric motor; the electric motor is used to convert the electrical energy into mechanical energy to drive the electric vehicle.

Description of drawings

Fig. 1 is a side view of a cell;

FIG. 2 is a schematic structural diagram of the cell shown in FIG. 1;

3A is a front view of a battery cell provided by an embodiment of the present application;

FIG. 3B is a side view corresponding to the cell shown in FIG. 3A according to an embodiment of the application;

FIG. 3C is a schematic diagram of the case where the cell shell provided by the embodiment of the application is a cylinder;

FIG. 4 is a schematic diagram of another battery cell according to an embodiment of the present application;

FIG. 5 is a schematic diagram of another battery cell according to an embodiment of the present application;

FIG. 6 is a schematic diagram of still another battery cell according to an embodiment of the present application;

FIG. 7 is a schematic diagram of another battery cell according to an embodiment of the present application;

FIG. 8 is a schematic diagram of another battery cell provided by an embodiment of the present application;

FIG. 9 is a top view of a battery pack according to an embodiment of the present application;

FIG. 10 is a side view of the battery pack shown in FIG. 9 according to an embodiment of the present application;

FIG. 11 is a front view of another battery pack provided by an embodiment of the application;

FIG. 12 is a side view of the battery pack corresponding to FIG. 11 according to an embodiment of the application;

13 is a schematic diagram of a power supply system provided by an embodiment of the application;

FIG. 14 is a schematic diagram of an electric vehicle according to an embodiment of the application.

detailed description

In order for those skilled in the art to better understand the technical solutions provided by the embodiments of the present application, the following first introduces the application scenarios of the technical solutions provided by the present application.

Referring to FIG. 1 and FIG. 2 together, FIG. 1 is a side view of a battery cell, and FIG. 2 is a schematic structural diagram of the battery cell shown in FIG. 1 .

Wherein, the cell in the figure includes a cell core body 1 and a cell shell.

The cell casing includes a cover plate 40 and a casing 50 .

The cover plate 40 is provided with a positive pole 10 , a negative pole 20 and an explosion-proof valve 30 .

The positive pole 10 and the negative pole 20 are connected to the battery core body 1 provided inside the casing.

The explosion-proof valve 30 is used to open the valve to release the pressure when the internal pressure of the cell casing is large, thereby preventing explosion.

However, the explosion-proof valve 30, the positive pole 10 and the negative pole 20 are arranged on the cover plate 40 together, and the positive pole 10 and the negative pole 20 will be connected to the power connection row and the sampling harness. When the electrolyte contacts the power connection bar and the sampling harness, a short-circuit ignition may occur, which may easily cause the battery to burn, thus posing a safety hazard.

In order to solve the above problems, the present application provides a battery cell, a battery pack, a system and an electric vehicle. Among them, the explosion-proof valve and the positive and negative poles of the battery are not set on the same plane, but on the side of the battery shell, so as to prevent the electrolyte vapor and electrolyte from contacting the power connection row when the explosion-proof valve is opened. and sampling harnesses, thereby avoiding short-circuit ignition and improving safety.

Those skilled in the art can understand the solutions of the present application more clearly, and the technical solutions in the embodiments of the present application will be described below with reference to the accompanying drawings in the embodiments of the present application.

Words such as "first" and "second" in the description of this application are only for descriptive purposes, and should not be construed as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features.

In this application, unless otherwise expressly specified and limited, the term "connection" should be understood in a broad sense. For example, "connection" may be a fixed connection, a detachable connection, or an integral body; it may be a direct connection, or a Indirect connections can be made through an intermediary.

It should be understood that the orientation descriptions such as "upper", "lower", "surface" and "side surface" in the present application are all directed to the positional relationship shown in the drawings of the present application.

The arrangement positions of the positive pole and the negative pole in the following embodiments can be exchanged.

Example 1:

The embodiments of the present application provide a battery core casing, which will be described in detail below with reference to the accompanying drawings.

See Figures 3A and 3B together. 3A is a front view of a cell casing provided by an embodiment of the application, and FIG. 3B is a side view corresponding to the cell shown in FIG. 3A .

The cell includes a cell body 1 and a cell shell 2 . The cell shell 2 is a closed shell, and the cell core body 1 is arranged inside the cell shell 2 .

The cell casing 2 is provided with a positive pole 10 , a negative pole 20 and an explosion-proof valve 30 .

The positive pole 10 and the negative pole 20 are located on the upper surface of the cell casing 2 and are connected to the cell body 1 inside the cell casing.

The explosion-proof valve 30 is located on the side of the cell housing 2 . It may be arranged on the side closer to the positive pole 10 or the side closer to the negative pole 20 , which is not specifically limited in the embodiment of the present application. In some embodiments, considering that the density of the gas is generally lower than that of the electrolyte, in order to discharge the gas inside the cell casing 2 as soon as possible to achieve rapid depressurization, the explosion-proof valve 30 is arranged on the upper end of the side of the cell casing 2 (ie, a higher place).

The explosion-proof valve 30 is used to open when the internal pressure of the cell casing 2 is greater than or equal to the valve opening pressure threshold, thereby reducing the internal pressure of the cell casing 2, thereby preventing the cell from exploding.

The cell shell 2 may be a cuboid, a cube, a cylinder or other shapes, and the embodiment of the present application does not specifically limit the shape of the cell shell. FIG. 3C shows a schematic diagram when the outer casing of the cell is a cylinder.

The positive and negative poles will be connected to the power connection row and the sampling harness, while the cell casing provided by the embodiment of this application has the explosion-proof valve set on the side of the cell casing, not on the same surface as the positive and negative poles. When the explosion-proof valve is opened When , the electrolyte vapor and part of the electrolyte taken out are directed to the side of the cell shell, so they will not contact the power connection bar and sampling harness, avoid short-circuit and ignition, and improve safety.

The following describes the specific implementation of the cell shell. For the convenience of understanding, the cell shell is used as a cuboid for illustration. Repeat them one by one.

Embodiment 2:

Referring to FIG. 4 , this figure is a schematic diagram of another battery cell according to an embodiment of the present application.

The battery cell includes a battery core body (not shown in the figure) and a battery core shell, and the battery core body is arranged in the battery core shell.

Wherein, the cell shell includes a cover plate 40 and a casing 50 .

The positive pole 10 and the negative pole 20 are located on the cover plate 40 . The cover plate 40 is the upper surface plate of the cell shell.

The side surface of the housing 50 is the side surface of the cell shell, and the explosion-proof valve 30 is arranged on the side surface of the housing.

The illustrated cover plate 40 and the casing 50 are connected to form a closed cell shell. Therefore, the casing 50 includes four side surfaces and a bottom surface.

The cover plate 40 and the casing 50 may be connected by welding or other connection methods, which are not specifically limited in the embodiment of the present application.

In the cell casing provided by the embodiment of the present application, the explosion-proof valve is arranged on the side of the shell of the cell casing, and the positive and negative poles are arranged on the side of the cell casing. When the explosion-proof valve is opened, the electrolyte vapor and Part of the electrolyte is directed to the side of the cell shell, so it will not touch the power connection bar and sampling harness, avoiding short-circuit ignition and improving safety.

Embodiment three:

The following describes another implementation manner of the cell housing.

Referring to FIG. 5 , this figure is a schematic diagram of yet another battery cell provided by an embodiment of the present application.

The cell housing of the illustrated cell includes a cover plate 40 and a housing 50 . The cover plate 40 includes a first surface 401 and a second surface 402 .

The second surface 402 is perpendicular to the first surface 401 and is connected to the side of the first surface 401 , that is, the side view of the cover plate 40 presents an “L” shape.

The explosion-proof valve 30 is located on the second surface 402 .

The second surface 402 is connected to the side of the housing 50 .

For the convenience of description, the second surface 402 is connected with the first side 501 of the housing 50, and the surface opposite to the first side 501 on the housing 50 is the second side 502. Continue referring to FIG. 5, in order to make the cover 40 and the The casing 50 is connected to form a closed cell shell, and the area of the side formed after the second surface 402 is connected to the first side 501 is equal to the area of the second side 502 .

The embodiment of the present application does not specifically limit the size of the area of the second surface 402 , but the second surface 402 should be sufficient to set the explosion-proof valve 30 .

The embodiment of the present application does not specifically limit the shape of the second surface 402. The second surface 402 in FIG. 5 is a rectangle, and the second surface 402 may also be a square. Also refer to the schematic diagram of the cell shown in FIG. 6 , in which the second surface 402 is a triangle; also refer to the schematic diagram of the cell shown in FIG. 7 , in which the second surface 402 is an irregular polygon. The shape of the first side on the housing 50 also changes accordingly with the shape of the second surface 402 .

The second surface 402 and the first side surface of the housing 50 may be connected by welding or other possible connection methods, which are not specifically limited in the embodiment of the present application.

Referring to FIG. 8 , this figure is a schematic diagram of yet another battery cell provided by an embodiment of the present application.

The cell shell of the illustrated cell is a cylinder, and the top surface is the first surface 401 of the cover plate 40 . 401 is vertical and connects the sides of the first surface 401 .

The explosion-proof valve 30 is located on the second surface 402 .

The cover plate 40 and the casing 50 form a closed cell casing for placing the cell cores.

To sum up, in the battery case provided by the embodiment of the present application, the explosion-proof valve is arranged on the side of the shell of the battery case, and the positive and negative poles are arranged on the cover plate of the battery case. When the explosion-proof valve is opened, the The discharged electrolyte vapor and part of the electrolyte are directed to the side of the cell shell, so they will not touch the power connection bar and sampling harness, avoid short-circuit ignition, and improve safety.

Embodiment 4:

Based on the battery cells provided in the above embodiments, the embodiments of the present application also provide a battery pack, which may include at least one battery cell described in the above embodiments. The electrolyte vapor and part of the electrolyte discharged from the explosion-proof valve are directed to the side of the cell casing, so they will not contact the power connection bar and sampling harness, avoiding short-circuit ignition and improving safety.

The following will continue to take the shape of the cell shell as a cuboid as an example for description. When the cell shell is in other shapes, the principle is similar, and the embodiment of the present application does not specifically limit it.

See Figures 9 and 10 together. 9 is a top view of a battery pack provided by an embodiment of the present application, and FIG. 10 is a side view of the battery pack shown in FIG. 9 provided by an embodiment of the present application.

The battery pack includes at least one battery cell and a liquid-conducting groove 60 .

The embodiments of the present application do not specifically limit the number of cells in the battery pack. In the figure, only the battery pack including four cells is used as an example for illustration.

For the specific description of the battery cell, reference may be made to the above embodiments, which will not be repeated in the embodiments of the present application.

The relative positions of the liquid-conducting grooves 60 of the plurality of cells are the same, for example, they are all disposed on the side adjacent to the negative electrode column 20 .

The explosion-proof valve 30 of each cell faces the tank body of the liquid guiding tank 60 .

The liquid guiding groove 60 is used to provide a directional flow channel for the gas, electrolyte vapor and part of the electrolyte discharged from the explosion-proof valve 30 when the explosion-proof valve 30 is opened.

The liquid guiding groove 60 also has the function of collecting the electrolyte vapor and part of the electrolyte discharged from the explosion-proof valve 30 .

To sum up, since the explosion-proof valve of the cell of the battery pack is set on the side of the cell shell, and the positive and negative poles are set on the cover plate (top surface) of the cell shell, when the explosion-proof valve is opened, the The electrolyte vapor and part of the electrolyte are directed to the side of the battery shell, and are collected and diverted directionally through the liquid guide groove, so they will not touch the power connection row and sampling harness, avoid short-circuit and ignition, and improve the battery pack. security.

Further, in some embodiments, a temperature sensor is provided in the liquid guiding tank 60, and the temperature sensor is used to detect the temperature in the liquid guiding tank 60, and send the detection result to the battery management system of the battery pack (Battery Management System, BMS).

Usually, abnormal conditions such as overcharge and short circuit occur inside the cell, which will cause the internal temperature of the cell to rise. When the explosion-proof valve is opened to release the pressure, the temperature of the gas, electrolyte vapor and part of the electrolyte is relatively high, so it can pass The temperature sensor detects changes in temperature to determine whether there is a safety hazard. In some embodiments, the BMS determines that the explosion-proof valve 30 is currently opened when the detection result is used to determine that the temperature rises to exceed a preset threshold, posing a safety hazard.

In some embodiments, the temperature sensor is arranged at a position relatively close to the explosion-proof valve 30 to quickly and accurately detect the temperature change.

The embodiment of the present application does not specifically limit the number of temperature sensors provided in the liquid guiding tank 60 .

In some embodiments, the liquid guiding tank 60 may include only one temperature sensor, or a plurality of temperature sensors arranged at equal intervals.

In other embodiments, in order to more accurately determine the cells that open the explosion-proof valve 30 , a temperature sensor may be correspondingly provided at the explosion-proof valve 30 of each cell in the liquid guiding tank 60 .

The liquid guiding tank 60 may also be provided with a gas sensor, and the gas sensor is used to detect whether a preset type of gas appears in the liquid guiding tank, and send the detection result to the battery management system of the battery pack.

The embodiments of the present application do not specifically limit the type of the gas sensor. In practical applications, the type of gas sensor can be determined according to the type of gas generated when the cell is abnormal. For example, when carbon monoxide (CO) gas is generated when the battery cell is abnormal, a gas sensor for detecting carbon monoxide can be used.

In some embodiments, when the BMS uses the detection result of the gas sensor to determine that a preset type of gas is present in the liquid conduit, it is determined that the current explosion-proof valve 30 has been opened, and there is a potential safety hazard.

The embodiments of the present application do not specifically limit the number of gas sensors provided in the liquid guiding tank 60 .

In some embodiments, the liquid guiding tank 60 may include only one gas sensor, or a plurality of gas sensors arranged at equal intervals.

In other embodiments, in order to more accurately determine the cells that open the explosion-proof valve 30 , a gas sensor may be correspondingly provided at the explosion-proof valve 30 of each cell in the liquid guiding tank 60 .

The battery management system of the battery pack can determine whether the battery cell is faulty according to the detection results of the temperature sensor and the gas sensor.

In some embodiments, the liquid guiding tank further includes a fire protection module, and the fire protection module has functions of cooling down and extinguishing fire.

When the BMS determines that the explosion-proof valve 30 is opened using the detection result of the temperature sensor and/or the gas sensor, it sends a fire-fighting command to the fire-fighting module.

The fire-fighting module is used to trigger fire-fighting actions after obtaining the fire-fighting command, that is, to cool down and put out the fire.

To sum up, the BMS of the battery pack provided by the embodiment of the present application can timely and accurately determine the state of the explosion-proof valve through the detection results of the temperature sensor and/or the gas sensor, and can also trigger the fire protection module when it is determined that the explosion-proof valve 30 is open. fire action. In some embodiments, when the temperature sensor and/or the gas sensor is set in a one-to-one correspondence with the explosion-proof valve 30, the fire protection module can also be set in a one-to-one correspondence with the explosion-proof valve 30, and then the fire protection module can open the explosion-proof valve under the control of the BMS. The batteries are used for precise fire extinguishing.

11 and 12 together, FIG. 11 is a front view of another battery pack provided by an embodiment of the present application; and FIG. 12 is a side view of the battery pack corresponding to FIG. 11 provided by an embodiment of the present application.

Compared with FIG. 10 , the battery pack further includes a power protection cover plate 60 .

The power protection cover plate 60 covers the positive pole and the negative pole of the cells in the battery pack.

When the explosion-proof valve 30 is opened, although the gas, electrolyte vapor, electrolyte, etc. discharged from the explosion-proof valve 30 are directed to the side of the cell casing, some of the discharge may still come into contact with the positive pole, the negative pole and the power connection row. and sampling wiring harness, so the safety of the battery pack can be further improved by setting the power protection cover plate 60 .

Embodiment 5:

Based on the battery pack provided by the above embodiment, the embodiment of the present application further provides a power supply system, which will be described in detail below with reference to the accompanying drawings.

Referring to FIG. 13 , this figure is a schematic diagram of a power supply system provided by an embodiment of the present application.

The power supply system 100 provided in this embodiment of the present application includes a battery pack 200 .

For a specific description of the battery pack 200, reference may be made to the fourth embodiment above, and details are not described herein again in this embodiment of the present application.

The power supply system 100 is used to supply power to the connected loads, and the embodiment of the present application does not specifically limit the number of battery packs 200 in the power supply system. The power supply system 100 can be applied to fields such as communication base stations, data centers, energy storage power stations, and electric vehicles. In some embodiments, the type of battery pack 200 may be a lithium-ion battery pack.

To sum up, the battery pack of the power supply system provided by the embodiment of the present application adopts the battery cell provided by the above embodiment, and the explosion-proof valve of the battery cell is arranged on the side of the battery cell shell, not on the same surface as the positive and negative poles , When the explosion-proof valve is opened, the electrolyte vapor and part of the electrolyte are brought out to the side of the cell shell, so it will not touch the power connection row and sampling harness, avoid short-circuit ignition, and improve the safety of the power supply system.

In some embodiments, the battery pack further includes a liquid conduit that provides a directional flow path for gas, electrolyte vapor, and a portion of the electrolyte exhausted from the explosion-proof valve when the explosion-proof valve is opened. In other embodiments, a temperature sensor and/or a gas sensor are also included in the liquid guiding tank, and the BMS of the battery pack can timely and accurately determine the state of the explosion-proof valve through the detection results of the temperature sensor and/or the gas sensor, and can also be used when When it is determined that the explosion-proof valve is open, the fire-fighting action of the fire-fighting module in the liquid guide tank is triggered. The battery pack can also be provided with a power protection cover to further prevent the discharge of the explosion-proof valve from contacting the positive pole, the negative pole, the power connection row and the sampling wire harness, so as to improve the safety of the battery pack.

Embodiment 6:

Based on the battery pack provided by the above embodiment, the embodiment of the present application further provides an electric vehicle, which will be described in detail below with reference to the accompanying drawings.

Referring to FIG. 14 , this figure is a schematic diagram of an electric vehicle according to an embodiment of the present application.

The electric vehicle 400 includes a battery pack 200 and an electric motor 300 .

Wherein, the battery pack 200 is used to provide electric power for the electric motor 300 .

The electric motor 300 is used to convert electrical energy into mechanical energy to drive the electric vehicle 400 .

To sum up, the battery pack of the electric vehicle provided in the embodiment of the present application adopts the battery cell provided in the above embodiment, and the explosion-proof valve of the battery cell is arranged on the side of the battery cell shell, not on the same surface as the positive and negative poles , When the explosion-proof valve is opened, the electrolyte vapor and part of the electrolyte are brought out to the side of the battery shell, so it will not touch the power connection row and sampling harness, avoid short-circuit ignition, and improve the safety of electric vehicles.

In some embodiments, the battery pack further includes a liquid conduit, which provides a directional flow path for the gas, electrolyte vapor and part of the electrolyte discharged from the explosion-proof valve when the explosion-proof valve is opened. In other embodiments, a temperature sensor and/or a gas sensor are also included in the liquid guiding tank, and the BMS of the battery pack can timely and accurately determine the state of the explosion-proof valve through the detection results of the temperature sensor and/or the gas sensor, and can also be used when When it is determined that the explosion-proof valve is open, the fire-fighting action of the fire-fighting module in the liquid guide tank is triggered. The battery pack can also be provided with a power protection cover to further prevent the discharge of the explosion-proof valve from contacting the positive pole, the negative pole, the power connection row and the sampling wire harness, which further improves the safety of the electric vehicle.

It should be understood that, in this application, "at least one (item)" refers to one or more, and "a plurality" refers to two or more. "And/or" is used to describe the relationship between related objects, indicating that there can be three kinds of relationships, for example, "A and/or B" can mean: only A, only B, and both A and B exist , where A and B can be singular or plural. The character "/" generally indicates that the associated objects are an "or" relationship. "At least one item(s) below" or similar expressions thereof refer to any combination of these items, including any combination of single item(s) or plural items(s). For example, at least one (a) of a, b or c, can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c" ", where a, b, c can be single or multiple.

As mentioned above, the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand: The technical solutions recorded in the embodiments are modified, or some technical features thereof are equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions in the embodiments of the present application.

Claims

A battery cell is characterized in that it comprises a battery core body and a battery core casing, the battery core body is arranged inside the battery core casing, and the battery core casing comprises: a positive pole column, a negative pole column and an explosion-proof valve;

the positive pole and the negative pole are located on the upper surface of the battery shell;

The explosion-proof valve is located on the side of the battery shell;

The explosion-proof valve is used to open when the internal pressure of the battery cell shell is greater than or equal to the valve opening pressure threshold.
The cell according to claim 1, wherein the cell shell comprises a cover plate and a casing;

the positive pole and the negative pole are located on the cover plate;

The side surface of the casing is the side surface of the battery shell.
The cell according to claim 1, wherein the cell shell comprises a cover plate and a casing, and the cover plate includes a first surface and a second surface;

the second surface is perpendicular to the first surface and is connected to the side of the first surface;

the first surface is the upper surface of the battery shell;

the explosion-proof valve is located on the second surface;

The second surface is connected to the side of the housing.
The battery cell according to any one of claims 1-3, wherein the battery core shell is a cuboid, a cube or a cylinder.
A battery pack, characterized in that the battery pack includes at least one battery cell according to any one of claims 1-4.
The battery pack according to claim 5, further comprising: a liquid guiding groove;

The explosion-proof valve of the at least one cell shell faces the tank body of the liquid guiding tank

The liquid guiding groove is used to provide a directional flow channel for the gas and electrolyte discharged from the explosion-proof valve when the explosion-proof valve is opened.
The battery pack according to claim 6, wherein a temperature sensor is provided in the liquid guiding groove;

The temperature sensor is used for detecting the temperature in the liquid guiding tank, and sending the detection result to the battery management system BMS of the battery pack.
The battery pack according to claim 6, wherein a gas sensor is provided in the liquid guiding groove;

The gas sensor is used to detect whether a preset type of gas appears in the liquid guiding tank, and send the detection result to the battery management system BMS of the battery pack.
The battery pack according to any one of claims 7 or 8, wherein a fire protection module is arranged in the liquid guiding groove;

The BMS sends a fire fighting command to the fire fighting module when it is determined that the explosion-proof valve is open using the detection result;

The fire fighting module is configured to trigger a fire fighting action after acquiring the fire fighting command.
The battery pack according to any one of claims 5-9, further comprising a power protection cover;

The power protection cover plate covers the positive pole and the negative pole of the at least one battery cell.
A power supply system, comprising the battery pack according to any one of claims 5-10;

The power supply system is used to power the connected loads.
An electric vehicle, characterized in that it comprises an electric motor and the battery pack according to any one of claims 5-10;

the battery pack is used to provide electrical energy for the electric motor;

The electric motor is used to convert the electrical energy into mechanical energy to drive the electric vehicle.