CN109860740B

CN109860740B - Control method and device for relieving thermal runaway spread of battery pack and battery pack

Info

Publication number: CN109860740B
Application number: CN201910123540.1A
Authority: CN
Inventors: 谢杰; 秦学
Original assignee: Huawei Digital Power Technologies Co Ltd
Current assignee: Huawei Digital Power Technologies Co Ltd
Priority date: 2019-02-18
Filing date: 2019-02-18
Publication date: 2021-12-28
Anticipated expiration: 2039-02-18
Also published as: CN109860740A

Abstract

The embodiment of the application discloses a control method and device for relieving thermal runaway spread of a battery pack and the battery pack, relates to the technical field of batteries, and solves the problem that in the prior art, the weight of the battery pack is increased when the thermal runaway spread of the battery is relieved, so that the energy density of the battery pack is reduced. The specific scheme is as follows: the battery pack comprises a plurality of batteries, each battery comprises a battery core and a first switch, one end of the first switch is electrically connected with a positive pole post of the battery core, the other end of the first switch is electrically connected with a negative pole post of the battery core, a control end of the first switch is used for receiving a control signal, and the control signal is used for switching on the first switch when the voltage change rate of the battery or at least one battery adjacent to the battery position is greater than or equal to a first preset threshold value, or switching on the first switch when the temperature rise rate of the battery or at least one battery adjacent to the battery position is greater than or equal to a second preset threshold value.

Description

Control method and device for relieving thermal runaway spread of battery pack and battery pack

Technical Field

The embodiment of the application relates to the technical field of batteries, in particular to a control method and device for relieving thermal runaway spread of a battery pack and the battery pack.

Background

Under the dual pressure of energy crisis and environmental pollution, the motorization of automobile power systems is one of the important trends in automobile development. At present, lithium ion power batteries with higher energy density are mostly adopted in power battery systems of new energy automobiles. However, accidental safety accidents have made lithium ion power battery systems more questionable.

The accident of the existing power battery system is generally caused by the thermal runaway of the power battery. The thermal runaway of the power battery refers to a process of rapidly converting chemical energy into thermal energy at a certain temperature by using materials inside the power battery. The power battery system usually comprises a plurality of single power batteries connected in series and parallel, and after thermal runaway of part of the single power batteries occurs, heat energy violently released can affect the surrounding batteries, so that the surrounding batteries continue to generate thermal runaway due to high-temperature heating. Such a process in which the surrounding battery is affected by the existing thermal runaway and then the thermal runaway occurs is called a thermal runaway propagation process. The thermal runaway is very dangerous to expand, which means that after the thermal runaway of the power battery system locally occurs, the thermal runaway of the whole system can occur due to the expansion of the thermal runaway. Therefore, the thermal runaway expansion in the power battery system is prevented, the thermal runaway is limited locally, the safety performance of the power battery system can be greatly improved, and the life and property safety of people is ensured.

One existing method for preventing thermal runaway propagation is to provide a set of fluid ducts surrounding all the cells in a battery system, and the ducts store a coolant. When the thermal runaway of the battery core is determined by detecting the temperature of the battery core, the thermal runaway battery core is cooled by spraying cooling liquid on the thermal runaway battery core, and the purpose of preventing the thermal runaway from spreading is achieved. Another conventional method for preventing thermal runaway propagation is to use a composite plate formed by combining a heat-conducting shell, a phase-change material and a partition plate, and to arrange the composite plate in a gap between batteries, so that thermal runaway propagation is effectively prevented, and the safety of a battery pack is improved.

However, the method has a large change on the battery pack, and the volume and the weight of the battery pack are increased and the energy density of the battery pack is reduced by arranging a pipeline surrounding all the single batteries or arranging the composite plates between the battery cores. In addition, because the temperature conduction has a hysteresis effect, the thermal runaway of the battery cell is determined by detecting the temperature of the battery cell, and the intervention on the thermal runaway battery cell cannot be realized at an early stage.

Disclosure of Invention

The embodiment of the application provides a control method and device for relieving thermal runaway propagation of a battery pack and the battery pack, and can intervene a thermal runaway cell and adjacent cells thereof in advance while not significantly influencing the energy density of the battery pack, so that the thermal runaway propagation is effectively relieved or prevented.

In order to achieve the above purpose, the embodiment of the present application adopts the following technical solutions:

in a first aspect of the embodiments of the present application, a battery pack is provided, where the battery pack includes a plurality of batteries, each battery includes an electric core and a first switch, where one end of the first switch is electrically connected to a positive electrode terminal of the electric core, another end of the first switch is electrically connected to a negative electrode terminal of the electric core, a control end of the first switch is configured to receive a control signal, and the control signal is configured to turn on the first switch when a voltage change rate of the battery or at least one battery adjacent to the battery position is greater than or equal to a first preset threshold, or turn on the first switch when a temperature rise rate of the battery or at least one battery adjacent to the battery position is greater than or equal to a second preset threshold. Based on the scheme, when the battery or the adjacent battery of the battery is in thermal runaway, the battery in the battery pack can receive the control signal to enable the first switch to be switched on, the battery starts to self-discharge, and the residual capacity of the battery is reduced. Because the lower the residual capacity of the battery, the lower the intensity when the thermal runaway occurs, the smaller the influence on the adjacent battery, and after the residual capacity of the battery is reduced due to the conduction of the first switch, the thermal runaway spread of the battery can be effectively relieved or prevented.

With reference to the first aspect, in a possible implementation manner, the positive electrode terminal of the battery pack is further configured to be electrically connected to one end of a load, and the negative electrode terminal of the battery pack is further configured to be electrically connected to the other end of the load. Based on the scheme, the self-discharge loop of the single battery is independent of the working loop of the battery pack.

With reference to the first aspect and the possible implementation manners, in another possible implementation manner, the one end of the first switch is electrically connected to a positive pole of the battery cell through a conductor; or, the other end of the first switch is electrically connected to the negative electrode post of the battery cell through the conductor. Based on this scheme, first switch can be connected through the conductor and the positive and negative utmost point post electricity of electric core to can constitute the self-discharge circuit when first switch switches on.

With reference to the first aspect and the possible implementation manners, in another possible implementation manner, the conductor is a conductive shell of the battery, or the conductor is a conductive material disposed on the shell of the battery; the conductive shell is an aluminum shell or a steel shell. Based on this scheme, first switch and the positive and negative utmost point post of electricity core can be connected through the electrically conductive casing electricity of electricity core, also can be connected through the electrically conductive material electricity that sets up on electric core casing.

With reference to the first aspect and the foregoing possible implementation manner, in another possible implementation manner, the battery further includes a first resistor, where the first resistor is connected in series between the first switch and the negative electrode post of the battery cell, or the first resistor is connected in series between the first switch and the positive electrode post of the battery cell. Based on this scheme, through set up first resistance between the positive post of first switch and electric core or negative pole post, can discharge through first resistance when first switch switches on.

With reference to the first aspect and the possible implementation manners, in another possible implementation manner, the resistance value of the first resistor is such that the discharge rate of the battery at the rated voltage is 1C. Based on this scheme, the resistance of first resistance makes the battery have suitable discharge rate to can further effectually alleviate and prevent the thermal runaway of battery and stretch.

In a second aspect of the embodiments of the present application, a control device for alleviating thermal runaway propagation of a battery pack is provided, where the control device includes a processor and the battery pack of the first aspect, and a control end of the first switch is connected to the processor; the processor is used for acquiring the voltage and the temperature of a first battery, wherein the first battery is a battery in the battery pack; the processor is further used for calculating the temperature rise rate and the voltage change rate of the first battery according to the voltage and the temperature of the first battery; if the voltage change rate of the first battery is determined to be larger than or equal to a first preset threshold value, or the temperature rise rate of the first battery is determined to be larger than or equal to a second preset threshold value, sending a control signal to the control ends of the first switches of the first battery and the one or more second batteries to enable the first switches of the first battery and the one or more second batteries to be conducted; the second battery is a battery adjacent to the first battery in the battery pack. Based on this scheme, can be when guaranteeing the energy density of battery package, through switch on the battery that takes place the thermal runaway and close on the self-discharge switch of battery, make it carry out self-discharge, reduce the residual capacity of thermal runaway battery and close on the battery to can alleviate and prevent the thermal runaway and spread. It can be understood that the second battery in the present scheme may be one or more batteries adjacent to a single side of the first battery, or may be a plurality of batteries adjacent to both sides of the first battery, that is, the present scheme may discharge through the first battery and the batteries adjacent to a single side of the first battery, or may discharge through the first battery and the batteries adjacent to both sides of the first battery, so as to alleviate or prevent the thermal runaway propagation of the first battery. It is noted that the discharge of the double-sided adjacent cell has a better effect of alleviating or preventing the thermal runaway propagation than the discharge of the single-sided adjacent cell.

With reference to the second aspect, in a possible implementation manner, the processor is further configured to send location information of the first battery. Based on this scheme, can take place under the thermal runaway's at first battery the condition, the positional information of output first battery to warn the driver or remind fortune dimension personnel in time to handle.

With reference to the second aspect and the foregoing possible implementation manner, in another possible implementation manner, the processor is further configured to output position information of the first battery if it is determined that the voltage change rate of the first battery is smaller than the first preset threshold, the temperature rise rate of the first battery is smaller than the second preset threshold, and the temperature rise rate of the first battery is greater than or equal to a third preset threshold; wherein the third preset threshold is smaller than the second preset threshold. Based on this scheme, can send the positional information of battery to carry out the early warning under the condition that the thermal runaway probably takes place for first battery, confirm through the temperature that the thermal runaway takes place or at battery package sustained combustion blowout smog and confirm thermal runaway again and control the comparison for prior art, this scheme can advance early warning time.

With reference to the second aspect and the foregoing possible implementation manners, in another possible implementation manner, the processor is further configured to obtain a voltage and a temperature of the second battery; calculating the temperature rise rate and the voltage change rate of the second battery according to the voltage and the temperature of the second battery; if the voltage change rate of the second battery is determined to be greater than or equal to the first preset threshold value, or the temperature rise rate of the second battery is determined to be greater than or equal to the second preset threshold value, sending a control signal to one or more third batteries to enable first switches of the one or more third batteries to be conducted; the third battery is a battery in the battery pack adjacent to the second battery. Based on the scheme, the parameters of the battery which starts the self-discharge can be further detected, the self-discharge effect is confirmed, and under the condition that the control effect of the thermal runaway is not ideal, more adjacent batteries are continuously started to perform the self-discharge, so that the thermal runaway spread of the battery is further relieved.

With reference to the second aspect and the foregoing possible implementation manners, in another possible implementation manner, the processor is further configured to output position information of the second battery. Based on the scheme, the position information of the second battery can be sent under the condition that the second battery is out of control due to heat, so that a driver is warned or operation and maintenance personnel are reminded to process the position information in time.

With reference to the second aspect and the foregoing possible implementation manner, in another possible implementation manner, the processor is further configured to output the position information of the second battery if it is determined that the voltage change rate of the second battery is smaller than the first preset threshold, the temperature rise rate of the second battery is smaller than the second preset threshold, and the temperature rise rate of the second battery is greater than or equal to the third preset threshold. Based on the scheme, the position information of the second battery which is possibly subjected to thermal runaway is sent to warn a driver or remind operation and maintenance personnel to process the battery which is possibly subjected to thermal runaway in time.

In a third aspect of the embodiments of the present application, a control method for alleviating thermal runaway propagation of a battery pack is provided, where the battery pack is the battery pack according to the first aspect, and the method includes: acquiring the voltage and the temperature of a first battery, wherein the first battery is a battery in the battery pack; calculating the temperature rise rate and the voltage change rate of the first battery according to the voltage and the temperature of the first battery; if the voltage change rate of the first battery is determined to be greater than or equal to a first preset threshold value, or the temperature rise rate of the first battery is determined to be greater than or equal to a second preset threshold value, sending a control signal to the control ends of the first switches of the first battery and the one or more second batteries to enable the first switches of the first battery and the one or more second batteries to be conducted, wherein the second battery is a battery adjacent to the first battery in the battery pack.

With reference to the third aspect, in a possible implementation manner, the method further includes: and outputting the position information of the first battery.

With reference to the third aspect and the foregoing possible implementation manners, in another possible implementation manner, the method further includes: if it is determined that the voltage change rate of the first battery is smaller than the first preset threshold, the temperature rise rate of the first battery is smaller than the second preset threshold, and the temperature rise rate of the first battery is greater than or equal to a third preset threshold, outputting the position information of the first battery; wherein the third preset threshold is smaller than the second preset threshold.

With reference to the third aspect and the foregoing possible implementation manners, in another possible implementation manner, the method further includes: acquiring the voltage and the temperature of the second battery; calculating the temperature rise rate and the voltage change rate of the second battery according to the voltage and the temperature of the second battery; if the voltage change rate of the second battery is determined to be greater than or equal to the first preset threshold, or the temperature rise rate of the second battery is determined to be greater than or equal to the second preset threshold, sending a control signal to one or more third batteries to enable a first switch of the one or more third batteries to be conducted, wherein the third batteries are batteries adjacent to the second batteries in the battery pack.

With reference to the third aspect and the foregoing possible implementation manners, in another possible implementation manner, the method further includes: and outputting the position information of the second battery.

With reference to the third aspect and the foregoing possible implementation manners, in another possible implementation manner, the method further includes: and if the voltage change rate of the second battery is smaller than the first preset threshold value, the temperature rise rate of the second battery is smaller than the second preset threshold value, and the temperature rise rate of the second battery is larger than or equal to the third preset threshold value, outputting the position information of the second battery.

For the above descriptions of the effects of the third aspect and the various implementations of the third aspect, reference may be made to the descriptions of the corresponding effects of the various implementations of the second aspect and the second aspect, which are not described herein again.

In a fourth aspect of the embodiments of the present application, a computer storage medium is provided, where computer program codes are stored in the computer storage medium, and when the computer program codes are run on a processor, the processor is caused to execute the control method for mitigating propagation of thermal runaway of a battery pack according to any one of the above aspects.

In a fifth aspect of the embodiments of the present application, a computer program product is provided, where the computer program product stores computer software instructions executed by the processor, and the computer software instructions include a program for executing the solution of the above aspect.

According to a sixth aspect of the embodiments of the present application, there is provided a control apparatus for mitigating propagation of thermal runaway of a battery pack, where the apparatus is in the form of a chip product, and the apparatus includes a processor configured to execute the control method for mitigating propagation of thermal runaway of a battery pack according to the third aspect. Optionally, the apparatus may further comprise a memory for coupling to the processor for storing necessary program instructions and data for the apparatus.

In a seventh aspect of the embodiments of the present application, there is provided an electric vehicle, where the electric vehicle includes an electric motor, and the control device for alleviating propagation of thermal runaway of the battery pack according to the second aspect is configured to supply power to the electric motor.

Drawings

Fig. 1 is a schematic structural diagram of a battery system according to an embodiment of the present disclosure;

fig. 2 is a schematic structural diagram of a battery module according to an embodiment of the present disclosure;

fig. 3 is a schematic structural diagram of a battery according to an embodiment of the present disclosure;

fig. 4 is a schematic structural diagram of another battery provided in the embodiment of the present application;

fig. 5 is a flowchart of a control method for alleviating thermal runaway propagation of a battery pack according to an embodiment of the present application;

fig. 6 is a schematic structural diagram of a battery module according to an embodiment of the present disclosure;

FIG. 7 is a flow chart for determining a thermal runaway risk level for a battery according to an embodiment of the present disclosure;

fig. 8 is a flowchart of another control method for alleviating propagation of thermal runaway of a battery pack according to an embodiment of the present application;

fig. 9 is a schematic composition diagram of a control device for alleviating thermal runaway propagation of a battery pack according to an embodiment of the present application;

fig. 10 is a schematic composition diagram of an electric vehicle according to an embodiment of the present application;

fig. 11 is a schematic composition diagram of another control device for alleviating thermal runaway propagation of a battery pack according to an embodiment of the present application;

fig. 12 is a schematic composition diagram of another control device for alleviating thermal runaway propagation of a battery pack according to an embodiment of the present application.

Detailed Description

An embodiment of the present application provides a control method for alleviating thermal Battery pack runaway and spread, which is applied to a Battery System, as shown in fig. 1, the Battery System 100 includes a Battery Management System (BMS) 101, at least one Battery module 102, a Battery measurement unit 103, a Controller Area Network (CAN) bus 104, a memory 105, and the like.

The battery management system 101 is a core component of the battery system 100, and the battery management system 101 may be a processor. The processor may be a central processing unit, a general purpose processor, a digital signal processor, a microcontroller or microprocessor, or the like. Further, the processor may also include other hardware circuits or accelerators, such as application specific integrated circuits, field programmable gate arrays or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. Which may implement or perform the various illustrative logical blocks, modules, and circuits described in connection with the disclosure. A processor may also be a combination of computing functions, e.g., a combination of one or more microprocessors, a digital signal processor and a microprocessor, or the like.

Illustratively, the battery management system 101 is configured to analyze the battery parameters detected by the battery measurement unit 103 and implement protection of the battery pack through a specific algorithm. For example, the estimation Of the State Of Charge (SoC), the estimation Of the State Of Health (SOH), the estimation Of the State Of battery, online diagnosis and early warning, charging, discharging and pre-charging control, equalization management, thermal management and the like can be realized, the utilization rate Of the battery can be improved, the overcharge and overdischarge Of the battery can be prevented, and the service life Of the battery can be prolonged.

The battery management system 101 may transmit signals to a vehicle controller, a motor controller, and other devices in real time through the high-speed CAN bus, adjust output power of the battery system, and receive control commands transmitted from the vehicle controller, a cab, a remote monitoring device, and the like.

For example, as shown in fig. 1, the battery management system 101 in the present application may be connected to the first switch of each battery in the battery module through a signal line, and configured to send a control signal to a control terminal of the first switch (self-discharge switch) of the battery, so that the battery starts to discharge after the self-discharge switch is turned on.

The battery module 102 includes one or more batteries, the battery module 102 may be composed of a plurality of batteries connected in series, in parallel, or in series-parallel, and one battery module 102 includes only one pair of positive and negative output terminals. For example, as shown in fig. 2, the battery module includes 12 batteries, the 12 batteries are connected in 3 parallel 4 strings, and the battery module includes only one pair of positive and negative electrode output terminals. Fig. 2 illustrates only a 3-to-4-string connection method, and the 12 batteries may be connected in another method such as a 2-to-6-string connection method, which is not limited in the embodiment of the present application. For example, the battery in the present application may be a lithium ion battery. It can be understood that a plurality of batteries can be connected in series or in parallel, after the batteries are connected to form a battery module, the batteries are connected in series and parallel to form a battery pack, and a positive pole column and a negative pole column of the battery pack are respectively electrically connected with two ends of a load and used for supplying power to the load.

The battery measuring unit 103 is used for detecting parameters of the battery pack, and comprises total voltage, total current, single battery voltage detection (preventing overcharge, overdischarge and even reverse pole phenomena), temperature detection (preferably, each battery string, a key cable connector and the like are provided with a temperature sensor), smoke detection (electrolyte leakage monitoring), insulation detection (leakage monitoring), collision detection and the like. The battery measurement unit 103 may be integrated in the battery management system 101 or may be provided separately from the battery management system 101.

The CAN bus 104 is a standard bus of an automobile computer control system and an embedded industrial control local area network, has the characteristics of strong real-time performance, strong anti-interference capability, simple structure, convenient application, low price and the like, and is widely applied to the field of electric automobiles. As shown in fig. 1, the battery management system 101 may obtain parameters collected by the battery measurement unit 103 through a CAN bus, and the battery management system 101 may communicate with the vehicle controller and the motor controller through the CAN bus.

The memory 105 may be used to store software programs and modules, and the battery management system 101 executes various functional applications and data processing of the battery management system 101 by running the software programs and modules stored in the memory 105. Memory 105 may include one or more computer-readable storage media. The memory 105 includes a program storage area and a data storage area, wherein the program storage area may store an operating system, an application program required for at least one function, and the like, for example, a program implementing the method for mitigating the propagation of thermal runaway provided by the embodiment of the present application. The storage data area may store battery parameters and the like detected by the battery measurement unit 103.

In this embodiment, the memory 105 may specifically include a volatile memory (volatile memory), such as a random-access memory (RAM); the memory may also include a non-volatile memory (non-volatile memory), a flash memory (flash memory), a hard disk (HDD) or a solid-state drive (SSD); the memory may also comprise a combination of memories of the kind described above.

It is to be understood that fig. 1 is merely exemplary, and that in practice, the battery system may include more or fewer components than shown in fig. 1; the structure shown in fig. 1 does not set any limit to the battery system provided by the embodiment of the present application.

The embodiment of the application also provides a battery pack, which comprises a plurality of batteries connected in series and parallel to form the battery pack. Each battery in the battery pack comprises a battery core 301 and a first switch 302, wherein one end (a) of the first switch 302 is electrically connected with a positive pole post of the battery core 301, the other end (b) of the first switch 302 is electrically connected with a negative pole post of the battery core 301, and a control end (c) of the first switch 302 is used for receiving a control signal, and the control signal is used for switching on the first switch 302 when the voltage change rate of the battery or at least one battery adjacent to the battery position is greater than or equal to a first preset threshold value, or switching on the first switch 302 when the temperature rise rate of the battery or at least one battery adjacent to the battery position is greater than or equal to a second preset threshold value. For example, the control signal may be sent by the battery management system 101 in fig. 1, the first switch 302 is a self-discharging switch, and the battery starts to self-discharge after the first switch is turned on.

Illustratively, the positive electrode pole of the battery pack is further used for being electrically connected with one end of a load, and the negative electrode pole of the battery pack is further used for being electrically connected with the other end of the load. For example, the load may be a load in an electric vehicle working circuit, and a loop formed by electrically connecting the positive electrode pole of the battery pack, the load and the negative electrode pole of the battery pack may be the electric vehicle working circuit for powering the electric vehicle.

It should be noted that, in the single battery, the circuit formed by electrically connecting the positive electrode post of the battery cell 301, the first switch 302 and the negative electrode post of the battery cell 301 is a self-discharge circuit of the single battery, and the self-discharge circuit is independent of the working circuit of the battery pack (the circuit formed by the positive electrode post of the battery pack, the load and the negative electrode post of the battery pack).

In one implementation, as shown in fig. 3 (a), one end (a) of the first switch 302 is electrically connected to the positive pole of the battery cell 301 through the conductor 303. In another implementation, as shown in fig. 3 (b), the other end (b) of the first switch 302 is electrically connected to the negative electrode post of the battery cell 301 through the conductor 303. It can be understood that, in a case that the battery or at least one battery adjacent to the battery is in thermal runaway, the first switch 302 is turned on, so that a path is formed between the positive and negative poles of the battery core 301, the battery starts to self-discharge, and the remaining charge (SoC) of the battery can be reduced. Because the lower the residual capacity of the battery is, the lower the intensity of thermal runaway occurring, and the smaller the influence on the adjacent battery is, the thermal runaway spread of the battery can be effectively relieved or prevented after the self-discharge switch is turned on to reduce the SoC of the battery.

When the battery shown in fig. 3 is discharged by an external short circuit, the internal resistance of the battery is large, and the battery can be discharged by the internal resistance of the battery, thereby reducing the remaining capacity of the battery.

In another implementation manner, the battery further includes a first resistor 304, as shown in fig. 4, the first resistor 304 is connected in series between the first switch 302 and the negative electrode post of the battery cell 301, or the first resistor 304 is connected in series between the first switch 302 and the positive electrode post of the battery cell 301.

Illustratively, as shown in (a) or (b) of fig. 4, one end (a) of the first switch 302 is electrically connected to the positive pole post of the battery cell 301 through the conductor 303 and the first resistor 304, and the other end (b) of the first switch 302 is electrically connected to the negative pole post of the battery cell 301; alternatively, as shown in (c) or (d) of fig. 4, one end (a) of the first switch 302 is electrically connected to the positive electrode post of the battery cell 301, and the other end (b) of the first switch 302 is electrically connected to the negative electrode post of the battery cell 301 through the first resistor 304 and the conductor 303. Alternatively, as shown in fig. 4 (e), one end (a) of the first switch 302 is electrically connected to the positive electrode post of the cell 301 through the first resistor 304, and the other end (b) of the first switch 302 is electrically connected to the negative electrode post of the cell 301 through the conductor 303. Alternatively, as shown in fig. 4 (f), one end (a) of the first switch 302 is electrically connected to the positive electrode post of the cell 301 through the conductor 303, and the other end (b) of the first switch 302 is electrically connected to the negative electrode post of the cell 301 through the first resistor 304. In the embodiment of the present application, a specific connection manner of the first switch, the first resistor, and the electrical connection between the positive electrode terminal and the negative electrode terminal of the battery cell is not limited, and fig. 4 is only an exemplary illustration.

For example, the conductor 303 may be a conductive housing of the battery, or may be a conductive material disposed on the housing of the battery, which is not limited in the embodiments of the present application, and is only an exemplary illustration here.

For example, if the case of the battery is a conductive case, the conductive case may be an aluminum case or a steel case. If the casing of the battery is a non-conductive casing (for example, the casing material of the battery cell is an aluminum-plastic film or other non-conductive material), a conductive material may be disposed on the casing of the battery, and the first switch 302 may be electrically connected to the positive electrode post or the negative electrode post of the battery cell 301 through the conductive material. For example, the conductive material may be a conductive wire made of metallic copper, aluminum, a conductive polymer film, or the like. The embodiments of the present application are not limited to the specific category and form of the conductive material. It is understood that the battery can be ensured to have a proper discharge speed by arranging the conductive material with a proper sectional area and length in practical application.

It can be understood that if the resistance of the first resistor 304 is too small, the discharge current is too large, which may cause the heat generated by the battery to be too large, thereby causing a new safety risk; if the resistance value of the first resistor 304 is too large, the discharging speed is too slow, so that the SoC of the battery cannot be effectively reduced, and the purpose of alleviating the thermal runaway propagation is achieved.

Illustratively, the resistance of the first resistor 304 may be such that the discharge rate of the battery at the rated voltage is 1C, where C represents the discharge rate.

It is understood that the charge/discharge rate of the battery is equal to the charge/discharge current/rated capacity, and therefore, the discharge rate of 1C indicates that the discharge current is the same as the rated capacity of the cell, that is, the battery is discharged from the full charge state to the cut-off state within 1 hour. For example, the discharge current I when the rated capacity of the cell is 100Ah and the discharge rate is 1C_1CIs 100A.

It should be noted that, in the embodiment of the present application, specific values of the resistance value of the first resistor 304 are not limited, and are only exemplary. For example, the resistance value of the first resistor may also be such that the discharge rate of the battery at the rated voltage is 0.9C, which is not limited in the embodiment of the present application.

For example, the first switch 302 may be a Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) switch, a relay, or other controlled switches, which is not limited in the embodiments of the present application.

The battery that this application embodiment provided can receive the control signal that is used for turning on this battery from the discharge switch (first switch 302) when this battery or the battery that is close to with this battery takes place thermal runaway, and after first switch 302 turned on, the battery began from discharging, and the residual capacity SoC of battery reduces, because the residual capacity of battery is lower, the intensity when taking place thermal runaway just is lower, and the influence to neighbouring battery just is less, consequently opens and can effectually alleviate thermal runaway and spread after the self discharge switch reduces SoC.

In order to solve the problem that in the prior art, when the thermal runaway of the battery is relieved, too many auxiliary devices are additionally introduced, the weight of the battery pack is increased, and the energy density of the battery pack is reduced, the embodiment of the application provides a control method for relieving the thermal runaway spread of the battery pack.

The embodiment of the application provides a control method for alleviating thermal runaway propagation of a battery pack, the battery pack may be formed by connecting a plurality of batteries in series and in parallel, each battery in the battery pack may be any one of the batteries shown in fig. 3 or fig. 4, as shown in fig. 5, and the control method for alleviating thermal runaway propagation of the battery pack may include steps S501 to S504.

S501, obtaining operation parameters of the first battery.

It is understood that this step S501 may be performed by the battery management system 101 in fig. 1.

The first battery is any one battery in the battery pack. The operating parameters may include voltage, temperature, and current of the first battery, and the embodiment of the present application is not limited to specific operating parameters of the first battery.

For example, the step S501 may include: the battery measuring unit 103 detects the operation parameters of the first battery and reports the operation parameters to the battery management system 101, and the battery management system 101 receives the operation parameters measured by the battery measuring unit 103; alternatively, if the battery measurement unit 103 is integrated in the battery management system 101, the operation parameter of the first battery may be directly measured by the battery management system 101 in step S501. For example, the battery management system may obtain operating parameters for each battery at a fixed frequency.

For example, when a plurality of batteries are connected in parallel, the voltage at two ends of the parallel batteries is the same, so that the parallel module only needs to collect one battery voltage. For example, as shown in fig. 6, the battery module includes 12 single batteries, and 12 batteries are connected in 3-parallel-4 series, wherein 1# battery, 2# battery and 3# battery are connected in parallel, 4# battery, 5# battery and 6# battery are connected in parallel, 7# battery, 8# battery and 9# battery are connected in parallel, and 10# battery, 11# battery and 11# battery are connected in parallel, then since the voltages at both ends of the parallel batteries are the same, the parallel batteries can be used as a management unit, and only one voltage value can be collected. The 1# battery to the 12# battery in fig. 6 may be any one of the batteries shown in fig. 3 to 4, and fig. 6 illustrates an example in which only one end of the first switch 302 of each battery is electrically connected to the positive electrode post of the battery cell 301, and the other end of the first switch 302 is electrically connected to the negative electrode post of the battery cell 301.

Illustratively, when the operating parameters of the battery are collected by the sensor and reported to the BMS, each operating parameter may be uploaded after corresponding to the collection time information of the parameter and the location information of the battery, and the operating parameter of the first battery obtained in step S501 may carry the location information of the first battery and the collection time information of each parameter, so that the location information of a faulty battery can be located quickly when a certain battery is faulty.

And S502, determining the thermal runaway risk level of the first battery according to the operation parameters of the first battery.

The thermal runaway risk level may include a high risk and a low risk.

As shown in fig. 7, the determining the thermal runaway risk level of the first battery according to the operation parameters of the first battery in step S502 may include: steps S5021-S5024.

S5021, calculating the temperature rise rate and the voltage change rate of the first battery according to the voltage and the temperature of the first battery.

Illustratively, if the thermal runaway of the battery occurs, the temperature thereof changes rapidly and the voltage may fluctuate or drastically change, so that it is possible to determine whether the thermal runaway of the first battery occurs or not by the rate of temperature rise and the rate of voltage change of the first battery.

For example, the rate of temperature rise and the rate of voltage change of the first battery may be calculated based on voltage and temperature parameters of the first battery at different times.

And S5022, determining whether the voltage change rate is larger than or equal to a first preset threshold value.

For example, if it is determined that the voltage change rate is greater than or equal to the first preset threshold, determining that the thermal runaway risk level of the first battery is a high risk; if it is determined that the voltage change rate is smaller than the first preset threshold, step S5023 is further performed.

For example, taking the first preset threshold as 1V/s as an example, if the voltage change rate of the first battery is greater than or equal to 1V/s, that is, the voltage change speed of the first battery is fast, it is determined that the thermal runaway risk level of the first battery is high risk, and the first battery and its neighboring batteries may be immediately controlled to prevent or slow down the thermal runaway propagation of the first battery. And if the voltage change rate of the first battery is less than 1V/s, namely the voltage change of the first battery is not large, further judging the temperature rise rate of the first battery.

S5023, determining whether the temperature rise rate is larger than or equal to a second preset threshold value.

For example, if it is determined that the temperature rise rate is greater than or equal to the second preset threshold, the thermal runaway risk level of the first battery is determined to be a high risk; if it is determined that the temperature rise rate is smaller than the second preset threshold, step S5024 is further performed.

For example, taking the first preset threshold as 1 ℃/s as an example, if the temperature rise rate of the first battery is greater than or equal to 1 ℃/s, it is determined that the temperature rise of the first battery is fast, and it is determined that the thermal runaway risk level of the first battery is high risk, the first battery and its neighboring batteries may be immediately controlled to prevent or slow down the thermal runaway propagation of the first battery. If the temperature rise rate of the first battery is less than 1 ℃/s, whether the temperature rise rate is greater than or equal to a smaller preset threshold (a third preset threshold) is further judged.

S5024, determining whether the temperature rise rate is larger than or equal to a third preset threshold value.

The third preset threshold is smaller than the second preset threshold. If the temperature rise rate is determined to be greater than or equal to a third preset threshold, determining that the thermal runaway risk level of the first battery is low risk; and if the temperature rise rate is smaller than a third preset threshold, determining that the first battery is not in thermal runaway, namely the state of the first battery is normal.

For example, taking the third preset threshold as 0.1 ℃/s as an example, if the temperature rise rate of the first battery is greater than or equal to 0.1 ℃/s, that is, the temperature rise rate of the first battery is between 0.1 ℃/s and 1 ℃/s, determining that the thermal runaway risk level of the first battery is low risk, that is, the first battery may be in thermal runaway, and early warning a user; and if the temperature rise rate of the first battery is less than 0.1 ℃/s, determining that the state of the first battery is normal.

It should be noted that, in order to reduce the false alarm rate of the thermal runaway risk level of the battery, the embodiment of the application may determine the thermal runaway risk level of the first battery by performing steps S5021 to S5024 multiple times. For example, if it is determined that the thermal runaway risk level of the first battery at the first time is high risk, the preset time may be separated, and the thermal runaway risk level of the first battery is determined again through steps S5021-S5024, and if the thermal runaway risk level of the first battery is still high risk, step S503 is performed again.

It can be understood that, in the method for determining whether thermal runaway occurs in a battery according to the temperature rise rate and the voltage change rate, compared with the method for determining whether thermal runaway occurs according to the temperature in the prior art, the method for determining whether thermal runaway occurs in a battery according to the present embodiment can determine a thermal runaway battery in advance; and the accuracy of determining the thermal runaway battery through the two parameters of the temperature rise rate and the voltage change rate is higher.

And S503, if the thermal runaway risk level of the first battery is determined to be high risk, sending control signals to the first battery and one or more second batteries.

It is understood that this step S503 can be performed by the battery management system 101 in fig. 1.

The control signal is used to turn on a first switch 302 of a first battery and one or more second batteries, which are batteries in the battery pack adjacent to the first battery. By adjacent in location is meant that the cells are physically located adjacent. For example, all the batteries in the battery system may be numbered in advance according to the positional relationship set by the batteries, and then a second battery adjacent to the thermal runaway battery may be determined according to the positional relationship between the number of the first battery where the thermal runaway occurs and the battery.

It is understood that the one or more second batteries in this embodiment may be one or more batteries adjacent to a single side of the first battery, or may be a plurality of batteries adjacent to both sides of the first battery, that is, the present solution may be self-discharged by the first battery and the battery adjacent to the single side of the first battery, or may be self-discharged by the first battery and the battery adjacent to both sides of the first battery, so as to alleviate or prevent the thermal runaway propagation of the first battery, which is not limited in this embodiment of the present application. Here, only the plurality of second batteries are exemplified as batteries adjacent to both sides of the first battery.

As shown in fig. 6, if the thermal runaway of the 3# battery occurs, in order to alleviate and prevent the thermal runaway of the 3# battery from spreading to an adjacent battery, the first switch 302 of the 3# battery and at least one battery (such as the 1# battery, the 2# battery, the 4# battery, and the 5# battery) adjacent to the 3# battery may be turned on, the first switch 302 of the 1# battery, the 2# battery, the 3# battery, the 4# battery, and the 5# battery may start self-discharging after being turned on, and the remaining capacity (SoC) of the 1# battery to the 5# battery may decrease. Since the lower the remaining capacity of the battery is, the lower the severity at which thermal runaway occurs, the less influence is exerted on neighboring batteries, and therefore, the spread of thermal runaway can be effectively alleviated or prevented.

It should be noted that, after the first switch 302 of one battery in the multiple batteries connected in parallel is turned on, the positive electrode and the negative electrode of each battery in the parallel module are discharged through the first switch 302 of the battery, so that heat of the multiple batteries is concentrated on the one battery, which is not beneficial to alleviating the spread of thermal runaway, and therefore, the multiple batteries connected in parallel can be used as a minimum management unit, and the first switches 302 of the multiple batteries in the minimum management unit are turned on and off at the same time.

Referring to fig. 6, the 1# battery, the 2# battery and the 3# battery are connected in parallel, the 4# battery, the 5# battery and the 6# battery are connected in parallel, the 7# battery, the 8# battery and the 9# battery are connected in parallel, and the 10# battery, the 11# battery and the 11# battery are connected in parallel, so that each group of three batteries connected in parallel can be used as a minimum management unit, that is, the first switches 302 of all the batteries in the minimum management unit are simultaneously turned on and off. For example, if the thermal runaway of the 3# battery occurs, the first switch 302 of at least one battery adjacent to the position of the 3# battery may be turned on, such as the 1# battery, the 2# battery, the 4# battery and the 5# battery, but since the 4# battery is connected in parallel with the 5# battery and the 6# battery, the 4# battery, the 5# battery and the 6# battery may serve as a minimum management unit, the first switches 302 of the 1# battery, the 2# battery, the 3# battery, the 4# battery, the 5# battery and the 6# battery are all turned on, the 1# battery, the 2# battery, the 3# battery, the 4# battery, the 5# battery and the 6# battery are self-discharged, the remaining power is reduced, and the thermal runaway of the 3# battery can be effectively delayed.

And S504, if the thermal runaway risk grade of the first battery is determined to be high risk or low risk, outputting first prompt information.

The first prompt message includes a thermal runaway risk level for the first battery, and location information for the first battery.

For example, when it is determined that the thermal runaway risk level of the first battery is high risk or low risk, that is, when the thermal runaway of the first battery may occur, the thermal runaway risk level of the first battery and the position information of the first battery are output to warn a driver, and a monitoring system is uploaded to notify an operation and maintenance person to perform processing.

For example, the outputting the first prompt information may include sending the prompt information to a Vehicle Controller Unit (VCU) by the BMS, or directly outputting the first prompt information by the BMS, which is not limited in the embodiment of the present application.

It can be understood that, this application confirms the thermal runaway risk level of first battery through the temperature rise rate and the voltage change rate of battery, can be under the circumstances that the first battery probably takes place the thermal runaway (the thermal runaway risk level of first battery is high risk or low risk), output prompt message and carry out the early warning, thereby for confirming through the temperature among the prior art that the thermal runaway takes place or at battery package continuous combustion blowout smog and confirm the thermal runaway and control again and compare, this application can advance the early warning time, and carry out self discharge in advance to the battery that the possibility of taking place the thermal runaway is big (thermal runaway risk level is high), in order to alleviate or prevent that battery thermal runaway from spreading to other batteries.

The embodiment of the application provides a control method for relieving thermal runaway spread of a battery pack, which comprises the steps of obtaining operation parameters of a first battery; determining a thermal runaway risk level of the first battery according to the operating parameters of the first battery; if the thermal runaway risk level of the first battery is determined to be high risk, control signals are sent to the first battery and the one or more second batteries, and the control signals are used for turning on the first switches 302 of the first battery and the one or more second batteries. This embodiment is when guaranteeing the energy density of battery package, through the self-discharge switch who switches on the battery that takes place the thermal runaway and close to the battery with it, makes it carry out self-discharge treatment, reduces the residual capacity of thermal runaway battery and close to the battery to can alleviate and prevent the thermal runaway and spread. And the thermal runaway battery is determined through the battery temperature rise rate and the voltage change rate, and compared with the thermal runaway battery determined through the temperature in the prior art, the thermal runaway battery can be determined in advance, and the thermal runaway can be controlled earlier.

The application also provides a control method for alleviating thermal runaway propagation of a battery pack, and as shown in fig. 8, after steps S501-S504, the method further comprises steps S505-S508.

And S505, acquiring the operating parameters of the second battery.

And S506, determining the thermal runaway risk level of the second battery according to the operation parameters of the second battery.

And S507, if the thermal runaway risk level of the second battery is determined to be high risk, sending a control signal to one or more third batteries.

The control signal is used to turn on a first switch 302 of one or more third batteries, which are batteries in the battery pack adjacent to the second battery.

And S508, if the thermal runaway risk grade of the second battery is determined to be high risk or low risk, outputting second prompt information.

The second prompt includes a thermal runaway risk level for the second battery, and location information for the second battery. It can be understood that, in this embodiment, when the thermal runaway risk level of the first battery is a high risk, and the thermal runaway risk level of the second battery is a high risk or a low risk, the thermal runaway risk level of the second battery and the position information of the second battery are output to notify a user, that is, when the thermal runaway of the second battery may occur, the related information of the battery may be output to warn a driver, and the related information is uploaded to a monitoring system to notify an operation and maintenance person to perform processing.

The specific implementation of the steps S505 to S508 is the same as the steps S501 to S504, and reference may be made to the description of the steps S501 to S504, which is not repeated herein.

The method can circularly execute the steps S505-S508, further detect the parameters of the battery which starts the self-discharge, confirm the self-discharge effect, and continuously start more adjacent batteries to perform the self-discharge under the condition that the control effect of the thermal runaway is not ideal, thereby further relieving the thermal runaway spread of the battery.

The embodiment of the application provides a control method for relieving thermal runaway spread of a battery pack, which comprises the steps of obtaining operation parameters of a second battery on the basis of the steps S501-S504; determining a thermal runaway risk level of the second battery according to the operating parameters of the second battery; and if the thermal runaway risk level of the second battery is determined to be high risk, sending a control signal to the second battery and one or more third batteries, wherein the control signal is used for conducting the first switches 302 of the one or more third batteries. In the embodiment, the self-discharge effect of the battery with the self-discharge started is confirmed, and when the battery with the self-discharge started is in thermal runaway, more adjacent batteries are continuously started to perform self-discharge, so that the risk of thermal runaway propagation is further reduced.

An embodiment of the present application further provides a control device for alleviating propagation of thermal runaway of a battery pack, and as shown in fig. 9, the control device 900 for alleviating propagation of thermal runaway of a battery pack may include: a processor 901 and a battery pack 902, the processor 901 configured to support the control apparatus 900 for mitigating the propagation of thermal runaway of the battery pack to perform S501-S504 in fig. 5, or S501-S508 in fig. 8, and/or other processes for the techniques described herein. The processor 901 may be the power management system BMS in fig. 1, or a chip or chip set in the power management system BMS. The battery pack 902 includes a plurality of batteries, and each battery in the battery pack 902 may be any of the batteries shown in fig. 3-4. As can be appreciated, the processor 901 is connected to the control terminal (c) of the first switch 302 of each battery in the battery pack 902 for turning on the first switch 302. All relevant contents of each step related to the above method embodiment may be referred to the functional description of the corresponding functional module, and are not described herein again.

An embodiment of the present application further provides an electric vehicle, as shown in fig. 10, the electric vehicle 1000 includes an electric motor 1001, and a control device 1002 for alleviating propagation of thermal runaway of a battery pack, where the control device 1002 for alleviating propagation of thermal runaway of a battery pack may be the control device for alleviating propagation of thermal runaway of a battery pack shown in fig. 9, and the control device 1002 for alleviating propagation of thermal runaway of a battery pack is used to supply power to the electric motor 1001. The specific functional structure of the control device 1002 for alleviating the thermal runaway propagation of the battery pack has been described in the foregoing embodiments, and is not described herein again. All relevant contents of each step related to the above method embodiment may be referred to the functional description of the corresponding functional module, and are not described herein again.

The above description has mainly introduced the scheme provided in the embodiments of the present application from the perspective of method steps. It will be appreciated that the computer, in order to carry out the above-described functions, may comprise corresponding hardware structures and/or software modules for performing the respective functions. Those of skill in the art will readily appreciate that the present application is capable of implementing the exemplary modules and algorithm steps described in connection with the embodiments disclosed herein in a combination of hardware and computer software. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

In the embodiment of the present application, functional modules may be divided according to the above method example, for example, each functional module may be divided corresponding to each function, or two or more functions may be integrated into one processing module. The integrated module can be realized in a hardware mode, and can also be realized in a software functional module mode. It should be noted that, in the embodiment of the present application, the division of the module is schematic, and is only one logic function division, and there may be another division manner in actual implementation.

In the case of dividing each functional module according to each function, fig. 11 shows a schematic structural diagram of a control device for alleviating propagation of thermal runaway of a battery pack according to the above embodiment, where the control device 1100 for alleviating propagation of thermal runaway of a battery pack includes: an acquisition module 1101, a processing module 1102 and a sending module 1103. The obtaining module 1101 may be configured to support the control apparatus 1100 for mitigating propagation of thermal runaway of the battery pack to execute S501 in fig. 5 or S505 in fig. 8; the processing module 1102 may be configured to support the control apparatus 1100 for mitigating the propagation of thermal runaway of the battery pack to execute S502 and S504 in fig. 5 or S506 and S508 in fig. 8; the sending module 1103 is configured to enable the control apparatus 1100 for mitigating propagation of thermal runaway of the battery pack to execute S503 in fig. 5 or S507 in fig. 8. All relevant contents of each step related to the above method embodiment may be referred to the functional description of the corresponding functional module, and are not described herein again. Referring to fig. 1 and 2, the control device 1100 for mitigating the thermal runaway propagation of the battery pack may be the power management system BMS shown in fig. 1 or 2 or a chip in the power management system BMS, which is not limited in the embodiment of the present application. At least one module of the control apparatus 1100 for mitigating the propagation of thermal runaway of the battery pack may be implemented in software, hardware, or a combination of software and hardware. When any one of the units is implemented in software, it can be executed by the processor in the power management system BMS in the corresponding embodiment of fig. 1 and stored in the memory 105. When any one of the units is implemented in hardware, it may be implemented in an integrated circuit, a circuit module, an electronic component, a processor, an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), or the like.

In the case of using an integrated unit, an embodiment of the present application further provides a control device for mitigating propagation of thermal runaway of a battery pack, as shown in fig. 12, where the control device 1200 for mitigating propagation of thermal runaway of a battery pack includes: a processor 1201. The processor 1201 is configured to control and manage actions of the control device for mitigating thermal runaway propagation, for example, the processor 1201 is configured to support the control device 1200 for mitigating thermal runaway propagation of the battery pack to execute S501-S504 in fig. 5, or S501-S508 in fig. 8, and/or other processes for the technology described herein, which may correspond to the power management system BMS in fig. 1. Optionally, the control apparatus 1200 for alleviating propagation of thermal runaway of a battery pack further includes a memory 1202, where the memory 1202 is used to store program codes and data of a computer, and may correspond to the memory 105 in fig. 1, and the description of all relevant contents of the above-mentioned components related to fig. 1 may be referred to the functional description of the corresponding components in fig. 12, and is not repeated herein. In another implementation, the structure of the control device for mitigating propagation of thermal runaway according to the above embodiment may further include a processor and an interface, where the processor is in communication with the interface, and the processor is configured to execute the embodiment of the present invention. The processor may be at least one of a Central Processing Unit (CPU), a Digital Signal Processor (DSP), a Microcontroller (MCU), or a microprocessor.

The present invention also provides an apparatus in the form of at least one chip, such as a chip set, the apparatus includes a processor and an interface circuit, the processor can receive user operations through the interface circuit, and optionally, the apparatus can further include a memory, the memory is coupled to the processor and stores necessary program instructions and data of the apparatus, and the processor is configured to execute the program instructions stored in the memory, so that the apparatus performs the function of the control apparatus for alleviating thermal runaway propagation in the above method. Alternatively, the memory may be a storage module in the chip, such as a register, a cache, and the like, and the storage module may also be a storage module located outside the chip, such as a ROM or other types of static storage devices that can store static information and instructions, a RAM, and the like.

The steps of a method or algorithm described in connection with the disclosure herein may be embodied in hardware or in software instructions executed by a processor. The software instructions may be comprised of corresponding software modules that may be stored in Random Access Memory (RAM), flash Memory, Erasable Programmable read-only Memory (EPROM), Electrically Erasable Programmable read-only Memory (EEPROM), registers, a hard disk, a removable disk, a compact disc read-only Memory (CD-ROM), or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such the processor can read information from, and write information to, the storage medium. Of course, the storage medium may also be integral to the processor. The processor and the storage medium may reside in an ASIC. Additionally, the ASIC may reside in a core network interface device. Of course, the processor and the storage medium may reside as discrete components in a core network interface device.

Those skilled in the art will recognize that in one or more of the examples described above, the functions described herein may be implemented in hardware, software, firmware, or any combination thereof. When implemented in software, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A storage media may be any available media that can be accessed by a general purpose or special purpose computer.

The above-mentioned embodiments, objects, technical solutions and advantages of the present application are further described in detail, it should be understood that the above-mentioned embodiments are only examples of the present application, and are not intended to limit the scope of the present application, and any modifications, equivalent substitutions, improvements and the like made on the basis of the technical solutions of the present application should be included in the scope of the present application.

Claims

1. A battery pack comprising a plurality of batteries, each battery comprising a cell and a first switch, wherein,

one end of the first switch is electrically connected with a positive pole column of the battery cell through a conductor, and the other end of the first switch is electrically connected with a negative pole column of the battery cell, or one end of the first switch is electrically connected with the positive pole column of the battery cell, and the other end of the first switch is electrically connected with the negative pole column of the battery cell through a conductor;

the control end of the first switch is used for receiving a control signal, and the control signal is used for enabling the first switch of the battery and at least one battery adjacent to the battery position to be conducted when the voltage change rate of the battery is larger than or equal to a first preset threshold value, or enabling the first switch of the battery and at least one battery adjacent to the battery position to be conducted when the temperature rise rate of the battery is larger than or equal to a second preset threshold value;

the battery further comprises a first resistor, wherein the first resistor is connected in series between the first switch and the negative pole of the battery cell, or the first resistor is connected in series between the first switch and the positive pole of the battery cell, and the first resistor is used for adjusting the discharging speed of the battery.

2. The battery pack of claim 1, wherein the positive terminal post of the battery pack is further configured to electrically connect with one end of a load, and the negative terminal post of the battery pack is further configured to electrically connect with the other end of the load.

3. The battery pack of claim 1 or 2, wherein the conductor is a conductive housing of the battery or a conductive material disposed on the housing of the battery.

4. The battery pack of claim 3, wherein the conductive housing is an aluminum or steel shell.

5. The battery pack according to claim 1 or 2, wherein the first resistor has a resistance value such that the discharge rate of the battery at a rated voltage is 1C.

6. A control device for alleviating propagation of thermal runaway in a battery pack, the device comprising a processor and the battery pack as claimed in any one of claims 1 to 5, wherein the control terminal of the first switch is connected to the processor;

the processor is used for acquiring the voltage and the temperature of a first battery, and the first battery is a battery in the battery pack;

the processor is further used for calculating the temperature rise rate and the voltage change rate of the first battery according to the voltage and the temperature of the first battery; if the voltage change rate of the first battery is determined to be greater than or equal to a first preset threshold value, or the temperature rise rate of the first battery is determined to be greater than or equal to a second preset threshold value, sending a control signal to the control ends of first switches of the first battery and one or more second batteries to enable the first switches of the first battery and the one or more second batteries to be conducted; the second battery is a battery in the battery pack adjacent to the first battery.

7. The apparatus of claim 6, wherein the processor is further configured to output the position information of the first battery if it is determined that the voltage change rate of the first battery is smaller than the first preset threshold, the temperature rise rate of the first battery is smaller than the second preset threshold, and the temperature rise rate of the first battery is greater than or equal to a third preset threshold; wherein the third preset threshold is smaller than the second preset threshold.

8. The apparatus according to claim 6 or 7,

the processor is further used for acquiring the voltage and the temperature of the second battery; calculating the temperature rise rate and the voltage change rate of the second battery according to the voltage and the temperature of the second battery; if the voltage change rate of the second battery is determined to be greater than or equal to the first preset threshold value, or the temperature rise rate of the second battery is determined to be greater than or equal to the second preset threshold value, sending a control signal to one or more third batteries to enable first switches of the one or more third batteries to be conducted; the third battery is a battery in the battery pack adjacent to the second battery.

9. The apparatus of claim 8, wherein the processor is further configured to output the position information of the second battery if it is determined that the voltage change rate of the second battery is smaller than the first preset threshold, the temperature rise rate of the second battery is smaller than the second preset threshold, and the temperature rise rate of the second battery is greater than or equal to a third preset threshold.

10. A control method for alleviating the spread of thermal runaway in a battery pack, wherein the battery pack is as claimed in any one of claims 1 to 5, the method comprising:

acquiring the voltage and the temperature of a first battery, wherein the first battery is a battery in the battery pack;

calculating the temperature rise rate and the voltage change rate of the first battery according to the voltage and the temperature of the first battery; if the voltage change rate of the first battery is determined to be larger than or equal to a first preset threshold value, or the temperature rise rate of the first battery is determined to be larger than or equal to a second preset threshold value, sending a control signal to the control ends of the first switches of the first battery and the one or more second batteries to enable the first switches of the first battery and the one or more second batteries to be conducted, wherein the second battery is a battery in the battery pack, and the position of the second battery is adjacent to the position of the first battery.

11. The method of claim 10, further comprising:

if the voltage change rate of the first battery is smaller than the first preset threshold value, the temperature rise rate of the first battery is smaller than the second preset threshold value, and the temperature rise rate of the first battery is larger than or equal to a third preset threshold value, outputting the position information of the first battery; wherein the third preset threshold is smaller than the second preset threshold.

12. The method according to claim 10 or 11, characterized in that the method further comprises:

acquiring the voltage and the temperature of the second battery;

calculating the temperature rise rate and the voltage change rate of the second battery according to the voltage and the temperature of the second battery; if the voltage change rate of the second battery is determined to be greater than or equal to the first preset threshold value, or the temperature rise rate of the second battery is determined to be greater than or equal to the second preset threshold value, a control signal is sent to one or more third batteries so that a first switch of the one or more third batteries is conducted, and the third batteries are batteries adjacent to the second batteries in the battery pack.

13. The method of claim 12, further comprising:

and if the voltage change rate of the second battery is smaller than the first preset threshold value, the temperature rise rate of the second battery is smaller than the second preset threshold value, and the temperature rise rate of the second battery is larger than or equal to a third preset threshold value, outputting the position information of the second battery.

14. An electric vehicle comprising an electric motor, and the control device for mitigating propagation of thermal runaway in a battery pack according to any one of claims 6 to 9, wherein the control device for mitigating propagation of thermal runaway in a battery pack is configured to supply power to the electric motor.