A battery pack, an electric device, a discharge control method, and a battery management system

Abstract

The application provides a battery pack, an electric device, a discharge control method and a battery management system, and relates to the technical field of batteries.The battery pack comprises a battery module, a heating module and a BMS.The battery module has at least one battery cell, and the heating module has at least one heater.Each heater is arranged in each battery cell and is led out from the inside of the battery cell.The BMS comprises a microprocessor and a controlled switch.The controlled switch is electrically connected between the positive electrode of the battery module and the negative electrode of the battery module and is configured to perform on-off operation in response to the control signal of the microprocessor.The heater is configured to form a circuit with the positive electrode of the battery module, the heater, the controlled switch and the negative electrode of the battery module to consume the electric energy of the battery module when the controlled switch is turned on.In the battery pack, only the controlled switch needs to be arranged in the BMS, and a complex discharge circuit does not need to be arranged, so that the space on the BMS can be saved, and the miniaturization of the BMS is facilitated.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular to a battery pack, an electric device, a discharge control method and a battery management system. BACKGROUND

[0002] With the continuous popularity of electric devices, there are often long periods of non-use of many electric devices. For example, for agricultural unmanned aerial vehicle devices, there are often long periods of non-use. In order to improve the safety performance of the battery module, the SOC (State Of Charge) of the battery module needs to be reduced below the SOC threshold when the battery module is at rest.

[0003] At present, a self-discharge circuit is usually designed on the BMS (Battery Management System), so as to discharge the entire battery module through the self-discharge circuit. However, the space on the BMS is very valuable, and the design of the self-discharge circuit will occupy the space of the BMS, which is not conducive to the miniaturization of the BMS. SUMMARY

[0004] The purpose of the embodiments of the present application is to provide a battery pack, an electric device, a discharge control method and a battery management system to improve the above problems.

[0005] The first aspect of the embodiments of the present application provides a battery pack, comprising a battery module, a heating module and a BMS, the battery module has at least one battery cell, the heating module has at least one heater; each of the heaters is arranged in each of the battery cells and is led out from the inside of the battery cell. The BMS comprises a microprocessor and a controlled switch, the controlled switch is electrically connected between the positive electrode of the battery module and the negative electrode of the battery module, and is configured to perform on-off operation in response to the control signal of the microprocessor. Wherein, the heater is configured to form a path in the circuit of the positive electrode of the battery module, the heater, the controlled switch and the negative electrode of the battery module when the controlled switch is turned on, so as to consume the electric energy of the battery module.

[0006] In the above implementation structure, when the battery module needs to be discharged, the microprocessor only needs to output a control signal to the controlled switch, so as to control the circuit formed by the positive electrode of the battery module, the heater, the controlled switch and the negative electrode of the battery module to be turned on, so that the heater in the battery cell consumes electricity, and the release of the electric energy in the battery module is realized. In the entire circuit structure, only the controlled switch needs to be arranged in the BMS, without the need to arrange a complex discharge circuit, which can save the space on the BMS and is conducive to the miniaturization of the BMS.

[0007] In a first alternative embodiment of the first aspect, the battery module comprises a plurality of battery cells, and the heating module comprises a plurality of heaters, each of the heaters corresponding to one of the battery cells, each of the heaters comprising at least two metal terminals leading from inside the battery cell and spaced apart from electrode terminals of the battery cell.

[0008] With the above implementation structure, each of the battery cells is provided with a heater, so that the rapid release of the electric energy of the battery module can be achieved through the plurality of heaters.

[0009] In a second alternative embodiment of the first aspect, the plurality of battery cells are connected in series between a positive electrode of the battery module and a negative electrode of the battery module.

[0010] In a third alternative embodiment of the first aspect, the BMS further comprises a data acquisition chip, the data acquisition chip being electrically connected to the electrode terminals of the battery cells and / or the heaters of the battery cells, and being electrically connected to the microprocessor.

[0011] In the above implementation structure, the data acquisition chip can be used to acquire the data related to the battery cells and the heaters, so that the controlled switch can be controlled to be turned on or turned off according to the data related to the battery cells and / or the heaters, thereby achieving more accurate and reliable discharge control of the battery module.

[0012] The second aspect of the embodiments of the present application further provides a discharge control method, applied to the microprocessor of the battery pack of the first aspect, the method comprising: in response to the battery module satisfying a preset self-discharge condition, sending a first control signal to the controlled switch to make the controlled switch perform a turn-on operation in response to the first control signal.

[0013] In the above implementation, when it is detected that the battery module satisfies the preset self-discharge condition, the microprocessor of the BMS sends a first control signal to the controlled switch to make the controlled switch perform a turn-on operation in response to the first control signal. In this way, the circuit formed by the positive electrode of the battery module, the heater, the controlled switch and the negative electrode of the battery module forms a path, so that the heater can consume the electric energy of the battery module, thereby achieving the effect of releasing the electric energy in the battery module.

[0014] In a first alternative embodiment of the second aspect, the self-discharge condition comprises: a time length from the last charging of the battery module exceeding a first time length threshold, and a current SOC value of the battery module being greater than an SOC threshold.

[0015] Through the implementation manner, the self-discharge of the battery module can be realized when the time length after the last charging of the battery module exceeds the first time length threshold and the current SOC value of the battery module is greater than the SOC threshold, and the safety performance of the battery module is improved.

[0016] In the second optional embodiment of the second aspect, after the first control signal is sent to the controlled switch, the method further includes: acquiring the temperature of each cell in the battery module; and sending a second control signal to the controlled switch to make the controlled switch perform the disconnection operation in response to the second control signal when the temperature of any cell is greater than a temperature threshold.

[0017] In the implementation manner, when the temperature of any cell is greater than a temperature threshold, the second control signal is sent to the controlled switch, so that the work of the heater is stopped, and a safety accident caused by the high temperature of the cell during the self-discharge process is avoided, and the safety of the battery during the self-discharge process is improved.

[0018] The third aspect of the embodiments of the present application further provides a battery pack, including a battery module, a heating module, and a BMS, the battery module has at least one cell, the heating module has at least one heater; each of the heaters is arranged in each of the cells and is led out from the inside of the cell; the heater is configured to work when a circuit formed by a positive electrode of the battery module, the heater, and a negative electrode of the battery module forms a path; the BMS includes a microprocessor and a data acquisition chip, one end of the data acquisition chip is electrically connected to the electrode terminal of each of the cells and / or the heater of each of the cells, and the other end of the data acquisition chip is connected to the microprocessor.

[0019] In the implementation structure, the data acquisition chip is electrically connected to the electrode terminal of each of the cells and / or the heater of each of the cells, and the data acquisition chip is connected to the microprocessor. In this way, during the work of the heater, the microprocessor can determine whether the heater is abnormal according to the collected data of the cells and / or the collected data of the heater, so that the situation that the heater is abnormal and causes a safety risk of the battery can be prevented.

[0020] The fourth aspect of the embodiments of the present application further provides a heater abnormality diagnosis method, which is applied to the third optional embodiment of the first aspect or the battery pack provided in the third aspect, and includes: receiving a parameter sent by the data acquisition chip; the parameter includes a current flowing through the heater, or a voltage of the cell, or capacity calculation information of the cell; and determining whether the heater is abnormal according to the parameter.

[0021] In the above implementation, the current flowing through the heater can reflect the heater condition, and the heater is arranged in the battery cell, and the voltage of the battery cell or the capacity of the battery cell can reflect the condition of the battery cell, thereby reflecting the influence of the heater in the battery cell on the battery cell. Therefore, whether the heater is abnormal can be determined by the current flowing through the heater, or the voltage of the battery cell, or the capacity of the battery cell, thereby preventing the case that the abnormal heater causes the battery safety risk.

[0022] In the first optional embodiment of the fourth aspect, when the parameter includes the current flowing through the heater, determining whether the heater is abnormal according to the parameter includes: determining whether the heater is abnormal according to the current flowing through the heater and a current threshold of the heater.

[0023] It can be understood that the current threshold of the heater is limited by the circuit structure and is generally fixed, for example, generally Vbattery / R, where Vbattery is the voltage applied to the heater, and R is the resistance of the heater. Therefore, when the current flowing through the heater exceeds the current threshold, the heater may be abnormal. Therefore, based on the above principle, the above implementation can accurately determine whether the heater is abnormal, thereby preventing the case that the abnormal heater causes the battery safety risk.

[0024] In the second optional embodiment of the fourth aspect, when the parameter includes the voltage of the battery cell, determining whether the heater is abnormal according to the parameter includes: determining a voltage change rate of the battery cell according to the voltage of the battery cell; determining whether the heater of the battery cell is abnormal based on the voltage change rate and a standard voltage change rate of the battery cell. The standard voltage change rate of the battery cell is the voltage change rate when the battery cell is normally working.

[0025] If the heater is not abnormal, the voltage change rate of the battery cell is determined when the battery cell is self-discharged through the heater. However, if the heater is abnormal, the voltage change rate will change. Therefore, in the above implementation, whether the heater of the battery cell is abnormal can be determined by the voltage change rate and the standard voltage change rate of the battery cell, thereby preventing the case that the abnormal heater causes the battery safety risk.

[0026] In an optional implementation of the second optional embodiment of the fourth aspect, before determining whether the heater of the battery cell is abnormal based on the voltage change rate and the standard voltage change rate of the battery cell, the method further includes: obtaining a current temperature of the battery cell; and determining whether the heater of the battery cell is abnormal based on the voltage change rate and the standard voltage change rate corresponding to the current temperature.

[0027] The voltage change rate of the battery cell is related to the temperature, and the standard voltage change rate at different temperatures is different. Therefore, by using the above implementation, it can be determined more accurately whether the heater of the battery cell is abnormal, and the risk of misjudgment is reduced.

[0028] In the third optional embodiment of the fourth aspect, when the parameter includes capacity calculation information of the battery cell, determining whether the heater is abnormal according to the parameter includes: determining a current battery cell capacity of the battery cell according to the capacity calculation information of the battery cell; and determining whether the heater of the battery cell is abnormal based on the current battery cell capacity of the battery cell.

[0029] In the fourth optional implementation of the fourth aspect, determining whether the heater of the battery cell is abnormal based on the current battery cell capacity of the battery cell includes: determining a current battery cell capacity change of the battery cell based on the current battery cell capacity of the battery cell and a previous battery cell capacity of the battery cell, wherein the previous battery cell capacity is a capacity calculated when the battery cell is last calculated; and determining whether the heater of the battery cell is abnormal based on the current battery cell capacity change of the battery cell and a standard capacity change corresponding to the battery cell. The standard capacity change is a capacity change value when the battery cell is normally working.

[0030] The capacity of the battery cell generally decays over time under normal circumstances, but if the heater in the battery cell is abnormal, the capacity change of the battery cell will be significantly abnormal due to the influence of the heater. Based on this, by using the above implementation, it can be determined whether the heater of the battery cell is abnormal, and the situation that the heater is abnormal and causes a battery safety risk can be prevented.

[0031] The fifth aspect of the embodiments of the present application further provides a battery pack, comprising a battery module, a heating module, and a BMS, the battery module having at least one battery cell, the heating module having at least one heater; each of the heaters is arranged in each of the battery cells and leads out from the inside of the battery cell; the BMS comprises a microprocessor and at least one controlled switch, the heaters and the controlled switches correspond to each other in one-to-one manner; the controlled switch is electrically connected between the positive electrode of the battery module and the negative electrode of the battery module and is configured to perform on-off operation in response to the control signal of the microprocessor; wherein each of the heaters is configured to: when the controlled switch corresponding to the heater is turned on, a circuit formed by the positive electrode of the battery module, the heater, the controlled switch corresponding to the heater, and the negative electrode of the battery module forms a path to heat the battery cell in which the heater is located.

[0032] In the above implementation structure, the on-off control of the heater in each battery cell can be realized through each controlled switch, thereby realizing the individual heating control of each battery cell and keeping the temperature of each battery cell as consistent as possible and reducing the temperature difference between the battery cells.

[0033] In the first optional embodiment of the fifth aspect, the battery module further comprises at least one temperature sensor; the temperature sensor corresponds to each of the battery cells in one-to-one manner and is electrically connected to the microprocessor.

[0034] In the above implementation structure, the temperature sensor is arranged for each battery cell, thereby making the temperature monitoring of each battery cell more accurate and the heating control in the battery cell more accurate.

[0035] In the second optional embodiment of the fifth aspect, the heaters in each of the battery cells are connected in parallel between the positive electrode of the battery module and the negative electrode of the battery module through the corresponding controlled switch.

[0036] The sixth aspect of the embodiments of the present application further provides a battery cell temperature control method, applied to the microprocessor of the battery pack provided in the sixth aspect, comprising: acquiring the current temperature of each battery cell in the battery module; determining the battery cell to be heated according to the current temperature of each battery cell; the battery cell to be heated is the battery cell with a temperature lower than a temperature threshold; sending a first control signal to the controlled switch corresponding to the heater in the battery cell to be heated, so that the controlled switch performs the turn-on operation in response to the first control signal.

[0037] In the implementation process, the first control signal is sent to the controlled switch corresponding to the heater in the to-be-heated battery cell with a temperature lower than the temperature threshold, so that the heater in the to-be-heated battery cell heats the to-be-heated battery cell, the to-be-heated battery cell is warmed up, and the temperatures of the battery cells are kept as consistent as possible, and the temperature difference between the battery cells is reduced.

[0038] In an optional embodiment of the sixth aspect, the method further includes: when the current temperature of the to-be-heated battery cell reaches the temperature threshold, sending a second control signal to the controlled switch corresponding to the heater in the to-be-heated battery cell, so that the controlled switch performs the opening operation in response to the second control signal.

[0039] In the implementation process, the second control signal is sent to the controlled switch corresponding to the heater in the to-be-heated battery cell when the current temperature of the to-be-heated battery cell reaches the temperature threshold, so that the heating of the to-be-heated battery cell is stopped, the temperature of the to-be-heated battery cell is prevented from being too high, and the problem of temperature imbalance between the battery cells is caused again.

[0040] The seventh aspect of the embodiments of the present application further provides a use-electricity device, including any one of the battery packs provided above.

[0041] The eighth aspect of the embodiments of the present application further provides a microprocessor configured to be able to execute a program to implement any one of the methods provided above.

[0042] The ninth aspect of the embodiments of the present application further provides a BMS including the microprocessor described above.

[0043] The tenth aspect of the embodiments of the present application further provides a BMS including a microprocessor and a controlled switch; the controlled switch is electrically connected between the positive electrode of the battery module and the negative electrode of the battery module, the controlled switch is also electrically connected with the microprocessor and is configured to perform the on-off operation in response to the control signal of the microprocessor; the microprocessor is configured to execute a program to implement the discharge control method described above.

[0044] The eleventh aspect of the embodiments of the present application further provides a computer readable storage medium, the computer readable storage medium stores one or more programs, and the one or more programs can be executed by one or more microprocessors to implement any one of the methods provided above. BRIEF DESCRIPTION OF DRAWINGS

[0045] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments of the present application. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope.

[0046] Figure 1 This is a schematic diagram of the basic structure of a battery pack provided in an embodiment of this application;

[0047] Figure 2 A schematic diagram of a battery cell structure provided in an embodiment of this application;

[0048] Figure 3 A schematic diagram of a battery pack structure that enables heater energization control is provided in an embodiment of this application;

[0049] Figure 4 A schematic diagram of another battery pack structure that enables heater power-on control, provided in an embodiment of this application;

[0050] Figure 5 This is a schematic diagram of a third type of battery pack structure that enables heater power-on control, provided in an embodiment of this application.

[0051] Figure 6 A schematic diagram of a battery pack structure with a data acquisition chip provided in an embodiment of this application;

[0052] Figure 7 A schematic diagram of another battery pack structure with a data acquisition chip provided in an embodiment of this application;

[0053] Figure 8 A schematic flowchart of a discharge control method provided in an embodiment of this application;

[0054] Figure 9 A schematic diagram of a battery pack structure with a temperature sensor provided in an embodiment of this application;

[0055] Figure 10 This application provides a schematic diagram of a battery pack structure capable of identifying heater malfunctions.

[0056] Figure 11 A schematic flowchart illustrating a heater anomaly diagnosis method provided in an embodiment of this application;

[0057] Figure 12 For the embodiments of this application in Figure 10 A schematic diagram of a battery pack structure with a temperature sensor is provided based on the above.

[0058] Figure 13 A schematic flowchart of a cell temperature control method provided in an embodiment of this application;

[0059] Figure 14 This is a structural schematic diagram of an electric two-wheeled vehicle provided in an embodiment of this application. Detailed Implementation

[0060] The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application.

[0061] Embodiment one:

[0062] The embodiments of the technical solutions of the present application will be described in detail below with reference to the drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present application, and therefore only serve as examples, and cannot limit the protection scope of the present application.

[0063] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs; the terms used herein are only for the purpose of describing specific embodiments of the present application, and are not intended to limit the present application; the terms "include" and "have" and any variations thereof in the specification and claims of the present application and the above description of drawings are intended to cover not exclusive inclusion.

[0064] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise explicitly specified.

[0065] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship between the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " in this paper generally represents that the front and rear associated objects are in an "or" relationship.

[0066] In this paper, the "embodiment" means that the specific features, structures or characteristics described in conjunction with the embodiment can be included in at least one embodiment of the present application. The appearance of this phrase in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment to other embodiments. Those skilled in the art can understand that the embodiments described herein can be combined with other embodiments.

[0067] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the technical term "electrically connected" can be directly connected, or indirectly connected through an intermediate medium, or the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above-mentioned term in the embodiments of the present application can be understood according to the specific circumstances.

[0068] At present, secondary batteries are widely used in electric bicycles, electric motorcycles, unmanned aerial vehicles, electric vehicles and other electric devices, as well as military equipment and aerospace and many other fields. With the continuous expansion of the application field of secondary batteries, the market demand is also increasing.

[0069] The present inventors have noticed that many battery modules will be in a long-time static state without use. The battery modules on agricultural unmanned aerial vehicles (electric devices) are more common in long-time static state without use. For example, when agricultural unmanned aerial vehicles are not used for operation in winter, the battery modules can be in a static state at this time. In addition, the battery modules will be in a long-time static state without use during the transportation stage (such as sea transportation). In order to improve the safety performance of the battery module when it is in a static state, it is necessary to reduce the SOC of the battery module to below the SOC threshold, and the battery module needs to be self-discharged to consume its own power to reduce its SOC. In the related art, a self-discharge circuit composed of a switch and a resistor is designed on the BMS circuit board, and the battery module is discharged by the self-discharge circuit of the microprocessor (such as Microcontroller Unit, MCU, micro control unit) on the BMS circuit board. However, the space on the BMS is limited, and the layout of the self-discharge circuit will occupy the space of the BMS, which will limit the layout of other electronic components and other circuits on the BMS on the one hand, causing the design and manufacturing process of the BMS circuit board to be complex and the manufacturing difficulty to be increased, and on the other hand, it is not conducive to the miniaturization and light weight of the BMS.

[0070] Therefore, in the embodiments of the present application, the present inventors propose a new battery pack structure, which sets the heater in the battery cell and extends from the inside of the battery cell to electrically connect with the BMS circuit board, and uses the built-in heater in the battery cell to discharge, thereby avoiding arranging a resistor on the BMS circuit board, reducing the space occupation of the BMS, and improving the design freedom of the circuit and electronic components on the BMS circuit board.

[0071] In order to facilitate the understanding of the scheme of the embodiments of the present application, the structure of the battery pack related to the present application will be introduced first:

[0072] Referring to Figure 1As shown, the battery pack includes a battery module and a BMS, wherein B+ is the positive electrode of the battery module, B- is the negative electrode of the battery module, P+ is the positive electrode terminal of the battery pack, and P- is the negative electrode terminal of the battery pack. The battery module can be electrically connected to the load of the electrical equipment through the positive electrode terminal P+ and the negative electrode terminal P- to supply power to the load of the electrical equipment. The BMS includes a microprocessor and a circuit (such as a data acquisition chip, etc.) electrically connected to the battery module for charging and discharging management of the battery module. The battery module can be composed of a plurality of battery monomers, and the plurality of battery monomers can be connected in series, in parallel, or in a mixed manner. The mixed connection means that there are both series connection and parallel connection among the plurality of battery monomers. The plurality of battery monomers can be directly connected in series, in parallel, or in a mixed manner to form a battery module. It can be understood that the battery module can also be formed by first connecting a plurality of battery monomers in series, in parallel, or in a mixed manner to form a battery pack, and then connecting a plurality of battery packs in series, in parallel, or in a mixed manner to form a whole. The battery module can also include other structures, such as a busbar component, for realizing electrical connection among the plurality of battery monomers, etc.

[0073] In the embodiments of the present application, the battery monomer can be a secondary battery including a lithium ion battery, a sodium ion battery, a magnesium ion battery, or a solid-state battery, etc., but is not limited thereto. The battery monomer can be in the shape of a cylinder, a flat body, a cuboid, or other shapes, etc. The battery monomer can be packaged in a soft package or a hard shell package.

[0074] In the embodiments of the present application, as shown in Figure 2 The heater 20 can be embedded or pre-embedded in the battery cell 10, and two connection terminals of the heater 20 can be extended from the inside of the battery cell 10 to the outside of the battery cell 10, and the heater 20 and the battery cell 10 are insulated from each other.

[0075] In a specific implementation manner of the present application, the heater 20 can be implemented by one or more resistors. When the heater 20 includes a plurality of resistors, the resistors can be connected in series, in parallel, or in a mixed manner to form the heater 20. The mixed connection means that there are both series connection and parallel connection among the plurality of resistors.

[0076] In the embodiments of the present application, each heater 20 includes at least two metal terminals 21, and the metal terminals 21 are extended from the inside of the battery cell 10, so that at least part of the metal terminals 21 are arranged outside the battery cell 10, and the part of the metal terminals 21 exposed outside the battery cell 10 is arranged to be spaced apart from the electrode terminal 11 of the battery cell 10 to avoid misdirecting the electrode terminal 11 of the battery cell 10 and the metal terminals 21.

[0077] Referring to Figure 3As shown, the battery pack includes a battery module 1, a heating module 2, and a BMS, which can be embodied in the form of a circuit board in some specific implementations. The battery module 1 has at least one battery cell 10, and the heating module 2 has at least one heater 20. Each heater 20 is arranged on each battery cell 10 and led out from the inside of the battery cell 10, for example, as shown. Figure 2 The heaters 20 in each battery cell constitute the heating module 2.

[0078] The BMS includes a microprocessor 30 and a controlled switch 31, which is electrically connected between the positive electrode B+ of the battery module 1 and the negative electrode B- of the battery module 1 and is configured to perform on-off operation in response to a control signal of the microprocessor 30.

[0079] When the controlled switch 31 is turned on, the circuit formed by the positive electrode B+ of the battery module 1, the heater 20, the controlled switch 31, and the negative electrode B- of the battery module 1 forms a path to consume the electric energy of the battery module 1.

[0080] Therefore, when the battery module 1 needs to be self-discharged, the microprocessor 30 can output a control signal to the controlled switch 31 to make the controlled switch 31 conductive, so as to control the circuit formed by the positive electrode B+ of the battery module 1, the heater 20, the controlled switch 31, and the negative electrode B- of the battery module 1 to be conductive, so that the heater 20 consumes electricity and releases the electric energy in the battery module 1. It can be seen that the heater is arranged on the battery cell, and only the controlled switch needs to be arranged on the BMS. On the one hand, the resistor originally arranged on the BMS is replaced by the heater arranged on the battery cell, which provides more space for the circuit layout and wiring on the BMS circuit board, and the remaining electronic components and circuit layout on the BMS circuit board have higher freedom, and on the other hand, there is no need to arrange a complex discharge circuit, which can save space on the BMS and facilitate the miniaturization and light weight of the BMS.

[0081] In the embodiments of the present application, the controlled switch 31 can be a device that is controlled to be conductive, such as an NMOS tube, a PMOS tube, a triode, an IGBT, and an optical coupler, but is not limited thereto.

[0082] It can be understood that in the embodiments of the present application, the battery module 1 can include a plurality of battery cells 10. At this time, the plurality of battery cells 10 can be connected in series between the positive electrode B+ of the battery module 1 and the negative electrode B- of the battery module 1. Of course, in the embodiments of the present application, the plurality of battery cells 10 can also be connected in parallel or mixed between the positive electrode B+ of the battery module 1 and the negative electrode B- of the battery module 1, which is not limited in the embodiments of the present application.

[0083] In one embodiment of the embodiments of the present application, the plurality of heaters 20 can be connected in series, for example, Figure 3As shown in FIG. 1, the battery module 1 includes a plurality of battery cells 10, and each battery cell 10 includes a heater 20. The battery module 1 further includes a BMS (Battery Management System) 30 and a plurality of controlled switches 31. The BMS 30 is configured to control the on-off operation of the controlled switches 31, and the controlled switches 31 are configured to control the power supply of the heaters 20 in the battery module 1.

[0084] In another embodiment of the present application, as shown in FIG. 2, the battery module includes at least one cell group, and each cell group includes at least one battery cell 10. The heaters 20 of the battery cells 10 in the same cell group are connected in series. The number of the controlled switches 31 can be the same as the number of the cell groups, and each controlled switch 31 corresponds to a cell group. Each controlled switch 31 is connected in series with the heaters 20 of the corresponding cell group, the positive electrode B+ of the battery module 1, and the negative electrode B- of the battery module 1, and is configured to perform the on-off operation in response to the control signal of the microprocessor 30. When any controlled switch 31 is turned on, the circuit formed by the positive electrode B+ of the battery module 1, the heaters 20 of the cell group corresponding to the controlled switch 31, the controlled switch 31, and the negative electrode B- of the battery module 1 forms a path to consume the electric energy of the battery module 1. Figure 4 In the structure shown in FIG. 2, each cell group is regarded as a heater group formed by the heaters 20 of the battery cells 10 in the cell group. The first branch connected by any heater group and the corresponding controlled switch 31 is connected in parallel with the second branch connected by another heater group and another controlled switch 31 between the positive electrode B+ of the battery module 1 and the negative electrode B- of the battery module 1, so that each controlled switch 31 can control whether the corresponding heater group is powered on or not.

[0085] Figure 4 In the structure shown in FIG. 2, each cell group is regarded as a heater group formed by the heaters 20 of the battery cells 10 in the cell group. The first branch connected by any heater group and the corresponding controlled switch 31 is connected in parallel with the second branch connected by another heater group and another controlled switch 31 between the positive electrode B+ of the battery module 1 and the negative electrode B- of the battery module 1, so that each controlled switch 31 can control whether the corresponding heater group is powered on or not.

[0086] In an optional example of the present application, as shown in FIG. 3, each cell group can include only one battery cell 10, so that the on-off operation of the heater 20 in each battery cell 10 can be controlled by the corresponding controlled switch 31. Figure 5 It can be understood that in the circuit structures shown in FIG. 2 and FIG. 3, the battery cells 10 can also be connected in series, in parallel, or in a mixed manner between the positive electrode B+ of the battery module 1 and the negative electrode B- of the battery module 1.

[0087] Figure 4 It can be understood that in the circuit structures shown in FIG. 2 and FIG. 3, the battery cells 10 can also be connected in series, in parallel, or in a mixed manner between the positive electrode B+ of the battery module 1 and the negative electrode B- of the battery module 1. Figure 5 In the embodiments of the present application, as shown in FIG. 4 and FIG. 5, the BMS of the battery pack can further include a data acquisition chip 32. The data acquisition chip 32 is electrically connected to the electrode terminals of the battery cells 10 and / or the heaters 20 of the battery cells 10, and is electrically connected to the microprocessor 30, and is configured to acquire the voltage and / or current data of the battery cells 10 and the heaters 20.

[0088] Figure 6 Based on the above Figure 7 Based on the above

[0089] Figures 3 to 7 ​​​​The battery pack shown, the application embodiment also provides a discharge control method applied to a microprocessor, please see Figure 8 The discharge control discharge includes:

[0090] S801: When it is detected that the battery module 1 meets the self-discharge condition, a first control signal is sent to the controlled switch 31 to make the controlled switch 31 perform conduction operation in response to the first control signal.

[0091] In an optional embodiment of the application, the self-discharge condition can include that the time interval from the last charging of the battery module 1 exceeds a first time threshold, and the current SOC value of the battery module 1 is greater than an SOC threshold.

[0092] Wherein, the first time threshold can be 5 days or 8 days or 10 days, it can be understood that the first time threshold can also be set to other time, the above 5 days, 8 days, 10 days are not as a specific limitation of the first time threshold of the application. The SOC threshold can be set to 60% or 70% or 90%. It can be understood that the SOC threshold can also be set to other values, the above 60%, 70%, 90% are not as a specific limitation of the SOC threshold of the application.

[0093] In the embodiment of the application, the BMS can record the time of the last time the charger is inserted, so as to determine whether the time interval from the last charging of the battery module 1 exceeds the first time threshold by comparing the time interval.

[0094] In the embodiment of the application, the first time threshold can be set to be greater than or equal to the time required for the power consumption equipment to enter the resting state, so that the battery module is self-discharged only in the resting state, so as to improve the safety performance of the battery module.

[0095] It can be understood that the resting state of the battery module in the application can be a state in which the battery pack is neither in a charging state nor in a discharging state. When the battery module is in the resting state, the BMS is in a dormant state.

[0096] In the embodiment of the application, after sending the first control signal to the controlled switch 31, the temperature of each battery cell 10 in the battery module 1 can also be obtained. When the temperature of any battery cell 10 is greater than a temperature threshold, a second control signal is sent to the controlled switch 31 to make the controlled switch 31 perform disconnection operation in response to the second control signal. When the controlled switch 31 performs disconnection operation in response to the second control signal, each heater 20 on the circuit where the controlled switch 31 is located stops working, thereby stopping heat production, and thus the safety accident caused by high temperature of the battery cell during self-discharge can be avoided, and the battery safety during self-discharge can be improved.

[0097] To obtain more accurate battery cell temperature information, in an optional embodiment of the present application, a temperature sensor 33 can be arranged on or around each battery cell 10, and each temperature sensor 33 is electrically connected to the microprocessor 30 or the data acquisition chip 32, so as to accurately obtain the temperature of each battery cell 10, for example Figure 9 as shown.

[0098] Of course, in the present application, a temperature sensor 33 can also be arranged around a plurality of battery cells 10, or only one temperature sensor 33 can be arranged in the battery module, so that the temperature data collected by the temperature sensor 33 can represent the temperature of the plurality of battery cells 10 and / or the battery module at the same time, thereby saving cost and reducing circuit complexity. For example, generally speaking, the temperature of the battery cell at the middle position of the battery module is higher than that of the battery cells at both ends, so the temperature sensor 33 can be arranged near the battery cell at the middle position, for example, the temperature sensor 33 can be arranged adjacent to the tab of the battery cell at the middle position, and for example, the temperature sensor 33 can also be arranged near the main body of the middle battery cell.

[0099] Based on the same inventive concept, the present application also provides a BMS, which comprises a microprocessor 30 and a controlled switch 31. The controlled switch 31 is configured to be electrically connected between the positive electrode of the battery module 1 and the negative electrode of the battery module 1, and the controlled switch 31 is also configured to perform on-off operation in response to the control signal of the microprocessor 30. The microprocessor 30 is configured to execute a program to implement the discharge control method described above.

[0100] The present inventors have also noticed that, in the embodiments of the present application, since the heater 20 is arranged in the battery cell 10, the heater 20 will generate heat after being powered on, thereby heating the battery cell 10 and causing the temperature of the battery cell 10 to rise. The temperature of the battery cell 10 can affect the safety of the battery cell 10, and if the battery cell 10 is in a high-temperature state for a long time, it is easy to cause thermal runaway risk, and in severe cases, it may even cause safety accidents such as battery smoking, fire, burning or explosion. In order to prevent and control these risks, it is necessary to identify and monitor the abnormal state of the heater 20 in the battery cell 10.

[0101] Therefore, in the embodiments of the present application, a battery pack is also provided, as shown in Figure 10 The battery pack comprises a battery module 1, a heating module 2, and a BMS. Similarly, the battery module 1 has at least one battery cell 10, and the heating module 2 has at least one heater 20. Each heater 20 is arranged in each battery cell 10 and is led out from the inside of the battery cell 10, and the structure of each battery cell 10 is as shown in Figure 2 .

[0102] Wherein, the heater 20 is configured to work when the circuit formed by the positive electrode B+ of the battery module 1, the heater 20 and the negative electrode B- of the battery module 1 forms a path.

[0103] The BMS includes a microprocessor 30 and a data acquisition chip 32, one end of the data acquisition chip 32 is respectively electrically connected with the electrode terminal of each battery cell 10 and the heater 20 of each battery cell 10, and the other end of the data acquisition chip 32 is electrically connected with the microprocessor 30.

[0104] During the working of the heater 20, the microprocessor 30 can judge whether the heater 20 is abnormal or not according to the collected data of the battery cell 10 or the collected data of the heater 20, so as to prevent the battery safety risk caused by the abnormal heater 20.

[0105] It can be understood that, although Figure 10 is not shown in the Figure 10 , the battery pack shown in the foregoing Figures 3 to 7 can have the design structure described in the foregoing, that is, each controlled switch 31 can be provided to realize the power-on control of each heater 20.

[0106] Based on the battery pack shown in the foregoing Figure 10 , or based on the battery pack shown in the foregoing Figure 6 or Figure 7 , the present application embodiment further provides a heater abnormality diagnosis method applicable to the microprocessor 30 of the battery pack shown in the foregoing Figure 10 , see Figure 11 , which comprises:

[0107] S1101: receiving the parameter sent by the data acquisition chip 32.

[0108] In the present application embodiment, the data acquisition chip 32 can collect the voltage, current and other data of the battery cell 10 through the electrical connection between the data acquisition chip 32 and the electrode terminal of the battery cell 10. The data acquisition chip 32 can collect the current flowing through the heater 20 and other data through the electrical connection between the data acquisition chip 32 and the heater 20.

[0109] In the present application embodiment, the parameter sent by the data acquisition chip 32 can include one or more of the current flowing through the heater 20, the voltage of the battery cell 10, and the capacity calculation information of the battery cell 10.

[0110] Wherein, the capacity calculation information of the battery cell 10 refers to information that can be used to calculate the capacity of the battery cell 10, which can include voltage, current and other information of the battery cell 10. When calculating the capacity, the capacity of the battery cell can be calculated based on the voltage, current and charging and discharging time and other information.

[0111] S1102: Determine whether the heater 20 is abnormal according to the parameter sent by the data acquisition chip 32.

[0112] In an optional implementation of the embodiment of the present application, when the parameter sent by the data acquisition chip 32 includes the current flowing through the heater 20, the step S1102 can include: determining whether the heater 20 is abnormal according to the current flowing through the heater and the current threshold of the heater 20.

[0113] It can be understood that the current threshold of the heater 20 is limited by the circuit structure and is generally fixed, for example, generally Vbattery / R, wherein Vbattery is the voltage applied to the heater, and R is the resistance of the heater. Therefore, when the current flowing through the heater exceeds the current threshold, the heater may be abnormal. Therefore, according to the current flowing through the heater and the current threshold of the heater 20, it can be determined to some extent whether the heater 20 is abnormal.

[0114] In another optional implementation of the embodiment of the present application, when the parameter sent by the data acquisition chip 32 includes the voltage of the battery cell 10, the step S1102 can include: determining the voltage change rate of the battery cell 10 according to the voltage of the battery cell 10, and determining whether the heater 20 of the battery cell 10 is abnormal based on the voltage change rate and the standard voltage change rate of the battery cell 10. Wherein, the voltage change rate refers to the change amount of the voltage of the battery cell 10 per unit time, and the standard voltage change rate is the voltage change rate possessed by a normal battery cell.

[0115] In a specific implementation, when the battery cell 10 is normally self-discharged, the voltage of the battery cell presents a downward trend, and the voltage change rate of the battery cell can be fixed or fluctuate within a small range, which can be understood as a small range of plus or minus 10%. However, if the heater 20 is abnormal, it may cause a micro-short circuit or a short circuit inside the battery cell 10 where the heater 20 is located, thereby causing the voltage change rate to change. Based on this, by comparing the voltage change rate of the battery cell 10 with the standard voltage change rate of the battery cell 10, when the voltage change rate of the battery cell 10 does not match the standard voltage change rate of the battery cell 10, it is determined that the heater 20 of the battery cell 10 is abnormal, which can prevent the situation that the heater 20 is abnormal and causes a battery safety risk.

[0116] Wherein, the standard voltage change rate of the battery cell 10 is an index value in the design stage of the battery cell, which can be obtained from the design specification of the battery cell.

[0117] In one of the embodiments of the present application, the electric core 10 corresponds to different standard voltage change rates at different temperatures, and when determining whether the heater is abnormal by the voltage change rate, the current temperature of the electric core 10 can be obtained first, and then based on the voltage change rate of the electric core 10 and the standard voltage change rate corresponding to the current temperature of the electric core 10, it is determined whether the heater 20 of the electric core 10 is abnormal. In this way, the influence of temperature is considered when determining, and the heater 20 of the electric core 10 can be more accurately determined to be abnormal, reducing the risk of misjudgment.

[0118] It can be understood that in the embodiments of the present application, on the basis of Figure 10 , a temperature sensor 33 can also be arranged on or around each electric core 10, and each temperature sensor 33 is connected with the microprocessor 30, so that the microprocessor 30 can accurately obtain the temperature of each electric core 10, for example Figure 12 as shown, or for example Figure 9 as shown.

[0119] In another optional embodiment of the embodiments of the present application, when the parameters sent by the data acquisition chip 32 include the capacity calculation information of the electric core 10, the step S1102 can include: determining the current electric core capacity of the electric core 10 according to the capacity calculation information of the electric core 10, and determining whether the heater 20 is abnormal based on the current electric core capacity of the electric core 10.

[0120] It can be understood that since the heater 20 is built into the electric core 10, when the heater 20 is abnormal, it is easy to cause a micro-short circuit or a short circuit in the electric core 10, and once a micro-short circuit or a short circuit occurs in the electric core 10, the decay rate of the electric core capacity of the electric core 10 will be higher than that of a normal electric core. Based on this principle, the current electric core capacity of the electric core 10 can be used to determine whether the heater 20 is abnormal.

[0121] For example, a normal electric core 10 usage time and electric core capacity reference corresponding relationship table can be preset, and the table records the correct correspondence between the usage time and the electric core capacity reference value of the electric core 10 under normal use. At the same time, a capacity allowable deviation can be set. Thus, when comparing, the usage time of the electric core 10 is determined first, and then the corresponding electric core capacity reference value is obtained by looking up the table. The deviation between the current electric core capacity of the electric core 10 and the electric core capacity reference value is calculated, and if the deviation is within the capacity allowable deviation range, it is considered that the electric core 10 is used normally, and it is determined that the heater 20 of the electric core 10 is normal. Otherwise, it is considered that the heater 20 of the electric core 10 is abnormal.

[0122] In another example, the current cell capacity change of the battery cell 10 can also be determined based on the current cell capacity of the battery cell 10 and the last cell capacity of the battery cell 10. The last cell capacity of the battery cell 10 refers to the cell capacity calculated in the last capacity calculation of the battery cell 10. Then, based on the current cell capacity change of the battery cell 10 and the standard capacity change corresponding to the battery cell 10, it is determined whether the heater 20 of the battery cell 10 is abnormal. The standard capacity change refers to the cell capacity change value of a normal battery cell.

[0123] Optionally, in the above example, the current cell capacity of the battery cell 10 can be obtained, and the last cell capacity of the battery cell 10 is compared with the current cell capacity of the battery cell 10. When the difference between the current cell capacity of the battery cell 10 and the last cell capacity of the battery cell 10 exceeds the capacity difference threshold, it is determined that the heater of the battery cell 10 is abnormal.

[0124] In a specific implementation manner of the present application, the above three optional implementation manners can be used simultaneously or any two of them can be used simultaneously. When at least two of the above three optional implementation manners are used simultaneously, it is determined that the heater 20 of the battery cell 10 is abnormal after the heater 20 of the battery cell 10 is determined to be abnormal in any optional implementation manner, and an alarm is given. Of course, it can also be set that the heater 20 of the battery cell 10 is determined to be abnormal only after all the ways determine that the heater 20 of the battery cell 10 is abnormal, and then an alarm is given; or it can also be set that the heater 20 of the battery cell 10 is determined to be abnormal only after at least two ways determine that the heater 20 of the battery cell 10 is abnormal, and then an alarm is given. The manner of finally determining that the heater 20 of the battery cell 10 is abnormal is not limited in the embodiments of the present application.

[0125] Through the above heater 20 abnormality diagnosis method, it can be effectively determined whether the heater 20 is abnormal, so that the heater 20 determined to be abnormal can be alarmed, so as to overhaul or replace the battery cell 10, or no longer allow the heater 20 to be used, so as to prevent the battery safety risk caused by the abnormal heater 20.

[0126] According to another aspect of the present application, the aim is to improve the uniformity and consistency of the temperature of each battery cell in the battery module 1. The degree of non-uniformity of the temperature of each battery cell 10 in the battery module 1 will affect the consistency of the discharge depth of each battery cell 10 in the battery module 1 and shorten the cycle life of the battery module 1. In addition, the non-uniform temperature distribution will cause uneven current distribution between the parallel branches formed by the battery cells 10 in the battery module 1, thereby deteriorating the consistency of the aging rate of each battery cell. Therefore, it is necessary to maintain the consistency of the temperature of each battery cell in the battery module 1. The present inventor has noticed that Figure 2The heater 20 in each battery cell 10 can heat the battery cell 10 after being powered on. Therefore, the embodiments of the present application also propose a way of individually controlling the heater 20 in each battery cell 10 in the battery module 1 to realize individual heating control of each battery cell 10 to ensure the temperature consistency of each battery cell in the battery module 1 as much as possible.

[0127] It can be seen from Figure 5 The battery pack shown includes the battery module 1, the heating module 2, and the BMS. Similarly, the battery module 1 has at least one battery cell 10, and the heating module 2 has at least one heater 20. Each heater 20 is arranged in each battery cell 10 and leads out from the inside of the battery cell 10. That is, the battery cell 10 adopts Figure 2 The battery cell 10 shown.

[0128] The BMS includes a microprocessor 30 and at least one controlled switch 31, and each heater 20 corresponds to one controlled switch 31. The controlled switch 31 is electrically connected between the positive electrode of the battery module 1 and the negative electrode of the battery module 1 and is configured to perform on-off operation in response to the control signal of the microprocessor 30. Wherein, each heater 20 is configured to: when the controlled switch 31 corresponding to the heater 20 is turned on, the circuit formed by the positive electrode B+ of the battery module 1, the heater 20, the controlled switch 31 corresponding to the heater 20, and the negative electrode B- of the battery module 1 forms a path to heat the battery cell 10 where the heater 20 is located.

[0129] Each heater 20 in each battery cell 10 forms a circuit branch through the corresponding controlled switch 31, and each circuit branch is connected in parallel between the positive electrode B+ of the battery module 1 and the negative electrode B- of the battery module 1.

[0130] Based on the above Figure 5 Or Figure 9 The battery pack shown, the embodiments of the present application also provide a battery cell temperature control method applied to the microprocessor 30 of the BMS, please see Figure 13 The method shown, including:

[0131] S1301: Obtain the current temperature of each battery cell 10 in the battery module 1.

[0132] In the embodiments of the present application, the microprocessor 30 can obtain the current temperature of each battery cell 10 in the battery module 1 through the connected temperature sensors 33.

[0133] S1302: Determine the battery cell 10 to be heated according to the current temperature of each battery cell 10.

[0134] In the embodiments of the present application, the battery cell 10 to be heated is the battery cell 10 whose temperature is lower than the temperature threshold.

[0135] In an embodiment of the present application, the temperature threshold can be slightly higher than the normal operating temperature of the battery cell 10 obtained in a conventional experiment, for example, the temperature threshold can be 30℃, or the temperature threshold can be slightly higher than the normal resting temperature of the battery cell 10 obtained in a conventional experiment, for example, the temperature threshold can be 10℃, so that through the action of the heater 20, the temperature of each battery cell 10 can be controlled to the temperature threshold as much as possible. In another embodiment of the present application, the temperature threshold can also be the highest temperature among the current temperatures of the battery cells 10 in the battery module 1, so that through the action of the heater 20, the temperature of all battery cells 10 can be increased to the temperature, ensuring the temperature consistency of the battery cells 10, making the use of the battery cells 10 more safe and reliable, and effectively prolonging the service life of the battery cells 10.

[0136] S1303: A first control signal is sent to the controlled switch 31 corresponding to the heater 20 in the battery cell 10 to be heated, so that the controlled switch 31 performs a conduction operation in response to the first control signal.

[0137] In an embodiment of the present application, when the current temperature of the battery cell 10 to be heated reaches the temperature threshold, a second control signal can also be sent to the controlled switch 31 corresponding to the heater 20 in the battery cell 10 to be heated, so that the controlled switch 31 performs a disconnection operation in response to the second control signal.

[0138] In this way, by sending the second control signal to the controlled switch 31 corresponding to the heater 20 in the battery cell 10 to be heated when the current temperature of the battery cell 10 to be heated reaches the temperature threshold, the heating of the battery cell 10 to be heated is stopped, which can avoid the problem of re-causing temperature imbalance among the battery cells 10 due to the over-high temperature of the battery cell 10 to be heated.

[0139] The microprocessor 30 described in the embodiments of the present application can be but is not limited to an MCU (Microcontroller Unit). The data acquisition chip 32 described in the embodiments of the present application can be but is not limited to an AFE (Analog Front End) chip. The controlled switch 31 and the controlled switch 31 described in the embodiments of the present application can be but are not limited to devices with controlled conduction and shutdown capabilities such as MOS tubes, triodes, optical couplers, etc., and the embodiments of the present application do not limit this.

[0140] Based on the same inventive concept, the embodiments of the present application also provide a power utilization device, which includes any one of the battery packs provided above.

[0141] The embodiments of the present application provide a battery module 1 as a power supply for an electric device. The electric device can be, but is not limited to, a mobile phone, a tablet, a notebook computer, an electric toy, an electric tool, a drone, an electric two-wheeled vehicle (such as an electric vehicle, an electric bicycle, etc.), an electric motorcycle, an electric tricycle, an electric car, a ship, a spacecraft, etc. The electric toy can include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, an electric plane toy, etc. The spacecraft can include an airplane, a rocket, a space shuttle, a spacecraft, etc.

[0142] The following embodiments take an electric two-wheeled vehicle as an example for convenience of description.

[0143] Please refer to Figure 14 , Figure 14 A structural schematic diagram of an electric two-wheeled vehicle 1400 provided by some embodiments of the present application is shown in FIG. 1. The electric two-wheeled vehicle 1400 is internally provided with a battery pack, which includes the battery module 1 and the BMS of any embodiment of the present application, and provides electric energy for the electric two-wheeled vehicle 1400.

[0144] Based on the same inventive concept, the embodiments of the present application provide a microprocessor 30 configured to be able to execute a program to implement any of the methods provided above.

[0145] The specific structure of the microprocessor 30 can refer to the implementation structure of the existing microprocessor, and will not be described here in detail.

[0146] Based on the same inventive concept, the embodiments of the present application also provide a BMS including the microprocessor 30 described above.

[0147] In addition, the BMS can also have the controlled switch 31 / controlled switch 31, the data acquisition chip 32 and other components described above. The specific implementation structure of the BMS is not limited in the present application.

[0148] Based on the same inventive concept, the embodiments of the present application also provide a computer readable storage medium, such as a floppy disk, an optical disk, a hard disk, a flash memory, a U disk, an SD (Secure Digital Memory Card) card, an MMC (Multimedia Card) card, etc. One or more programs are stored in the computer readable storage medium, and the one or more programs can be executed by one or more microprocessors to implement any of the methods described above. Details are not repeated here.

[0149] In the embodiments of the present application, it should be understood that the disclosed method can be implemented in other ways. The embodiments described above are only illustrative. The above-described only is the embodiment of the present application, and is not used to limit the protection scope of the present application. For those skilled in the art, various modifications and changes can be made to the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A battery pack, characterized by, The battery pack comprises a battery module, a heating module, and a battery management system, the battery module has at least one battery cell, the heating module has at least one heater; Each of the heaters is arranged in each of the battery cells and leads out from the inside of the battery cell; The battery management system comprises a microprocessor and a controlled switch, the controlled switch is electrically connected between the positive electrode of the battery module and the negative electrode of the battery module, and is configured to perform on-off operation in response to the control signal of the microprocessor; The heater is configured to form a path with the positive electrode of the battery module, the controlled switch, and the negative electrode of the battery module when the controlled switch is turned on, so as to consume the electric energy of the battery module; The battery management system further comprises a data acquisition chip, the data acquisition chip is electrically connected with the electrode terminal of each battery cell and / or the heater of each battery cell, and is electrically connected with the microprocessor; the data acquisition chip is used to acquire the parameters of the battery cell and / or the heater; the microprocessor is used to receive the parameters sent by the data acquisition chip, and determine whether the heater is abnormal according to the parameters; the parameters include the current flowing through the heater, or the voltage of the battery cell, or the capacity calculation information of the battery cell.

2. The battery pack of claim 1, wherein, The battery module comprises a plurality of battery cells, the heating module comprises a plurality of heaters, the heaters correspond to the battery cells one by one, each heater comprises at least two metal terminals, the metal terminals lead out from the inside of the battery cell and are arranged at intervals with the electrode terminal of the battery cell.

3. The battery pack of claim 1, wherein, The plurality of battery cells are connected in series between the positive electrode of the battery module and the negative electrode of the battery module.

4. The battery pack of claim 1, wherein, The microprocessor is further configured to send a first control signal to the controlled switch when the time length from the last charging of the battery module exceeds a first time length threshold and the current SOC value of the battery module is greater than an SOC threshold, so that the controlled switch performs the turn-on operation in response to the first control signal.

5. An electric device, characterized by The battery pack comprises the battery pack according to any one of claims 1-4.

6. A discharge control method characterized by, The discharge control method is applied to the battery pack according to any one of claims 1-4, and the discharge control method comprises: sending a first control signal to the controlled switch in response to the battery module satisfying a preset self-discharge condition, so that the controlled switch performs the turn-on operation in response to the first control signal; and receiving the parameters sent by the data acquisition chip and determining whether the heater is abnormal according to the parameters.

7. The discharge control method according to claim 6, wherein The self-discharge condition comprises: the time length from the last charging of the battery module exceeds a first time length threshold and the current SOC value of the battery module is greater than an SOC threshold.

8. The discharge control method according to claim 6, wherein After sending the first control signal to the controlled switch, the method further comprises: obtaining the temperature of each battery cell in the battery module; when the temperature of any battery cell is greater than a temperature threshold, sending a second control signal to the controlled switch, so that the controlled switch performs the turn-off operation in response to the second control signal.

9. A battery management system, characterized by, The battery management system comprises a microprocessor and a controlled switch; the controlled switch is electrically connected between the positive electrode of the battery module and the negative electrode of the battery module, and is also electrically connected with the microprocessor and configured to perform on-off operation in response to the control signal of the microprocessor; The microprocessor is configured to perform the discharge control method according to any one of claims 6-8.

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