Method and device for testing service life of battery pack circuit breaking unit and battery pack

Abstract

The invention relates to the technical field of batteries, and discloses a battery pack circuit breaking unit service life testing method and device and a battery pack, the battery pack circuit breaking unit belongs to the battery pack, and the testing method comprises the steps that the battery pack and a load simulation circuit are notified, the load simulation circuit executes one-time charging and discharging, and when the load simulation circuit executes charging, the load simulation circuit executes one-time discharging; the current flows from the battery pack to the load simulation circuit and is accumulated in the load simulation circuit; when the load simulation circuit executes discharging, the electric energy is consumed in the load simulation circuit; circularly executing the notification action; determining the service life of the battery pack circuit breaking unit according to the cycle index. The service life of the battery pack circuit breaking unit is measured, the test efficiency is high, the reliability is high, and the test result is accurate.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a method and device for testing the life of a circuit breaker unit of a battery pack, and a battery pack. Background Art

[0002] The core of electric vehicle technology lies in the "three-electric" system, namely the electric drive system, battery system and electronic control system. These three systems constitute the key technology of electric vehicles. The electric drive system is generally composed of a motor, a transmission mechanism and a converter. It is generally regarded as the load of the electric vehicle. The battery system, also known as the battery pack, is the core of the "three-electric" system and is used to power the electric drive system. It is also the most expensive and complex system among the "three-electric". The electronic control system is the main control console of the electric vehicle and is called the brain of the new energy vehicle.

[0003] The battery disconnect unit (BDU) in the battery system is a key connecting component between the battery system and the electric drive system, responsible for the on-off of the current between the battery system and the electric drive system. Its life directly affects the number of times an electric vehicle can start or stop. Therefore, it is particularly important to design and develop a method and device that can test the life of a battery disconnect unit. Summary of the invention

[0004] The present application provides a method for testing the life of a battery pack circuit breaker unit, which can measure the life of all components of the battery pack circuit breaker unit in the battery pack.

[0005] On the one hand, the present application proposes a method for testing the life of a battery pack disconnecting unit, wherein the battery pack disconnecting unit belongs to the battery pack. The method includes: notifying the battery pack and the load simulation circuit, wherein the load simulation circuit performs a charge and a discharge, wherein when the load simulation circuit performs a charge, current flows from the battery pack to the load simulation circuit and accumulates in the load simulation circuit; when the load simulation circuit performs a discharge, electric energy is consumed in the load simulation circuit; cyclically performing the notification action; and determining the life of the battery pack disconnecting unit according to the number of cycles.

[0006] Because the battery pack circuit breaker unit generally includes multiple components such as resistors and relays, this test method can test the life of all components in the battery pack circuit breaker unit at one time. The test efficiency is higher and more in line with the actual working conditions of electric vehicles.

[0007] In some implementations, the battery pack and the load simulation circuit are notified, and the load simulation circuit performs a charge including: sending an upper high voltage signal to the battery pack so that the battery pack disconnect unit performs an upper high voltage action; and sending a charging signal to the load simulation circuit so that the load simulation circuit absorbs the battery pack power. When the battery pack disconnect unit and the load simulation circuit perform charging, the upper high voltage signal is sent to the battery pack and the charging signal is sent to the load simulation circuit at the same time. In this way, the process of the battery pack charging the load can be restored, which is more in line with the actual use scenario of the electric vehicle starting.

[0008] In some implementations, the battery pack and the load simulation circuit are notified, and the load simulation circuit performs a discharge including: sending a lower high voltage signal to the battery pack so that the battery pack circuit breaker unit performs a lower high voltage action; sending a discharge signal to the load simulation circuit so that the load simulation circuit releases the absorbed electrical energy.

[0009] When the battery pack disconnect unit and the load simulation circuit are discharging, a high voltage signal is sent to the battery pack and a discharge signal is sent to the load simulation circuit at the same time. This can restore the load discharge process, making the test more consistent with the scenario of the electric vehicle shutting down during driving.

[0010] In some implementations, notifying the battery pack and the load simulation circuit so that the load simulation circuit performs a discharge includes: after being notified to perform a charging action, waiting for a first time period; or when the voltage of the load simulation circuit reaches a voltage threshold, notifying the battery pack and the load simulation circuit so that the load simulation circuit performs a discharge.

[0011] The lower high voltage of the battery pack requires the upper high voltage action to be completed. Therefore, by waiting for the first time period, or the voltage of the load simulation circuit reaches the voltage threshold, it means that the upper high voltage action of the battery pack is completed, and the lower high voltage and upper high voltage of the battery pack circuit breaker unit are closely connected, shortening the test time.

[0012] In some implementations, the cyclic execution of the notification action includes: after the notification executes a discharge action, after waiting for a second time period, executing the cyclic action. The battery pack executes the next cycle by waiting for the second time period, during which the battery pack completes the high voltage action. This method achieves a close connection between the two cycles and shortens the test time.

[0013] In some implementations, when the number of times the notification action is executed in a loop reaches the life threshold, the loop is stopped. Because when the number of times the notification action is executed in a loop reaches the life threshold, the battery pack circuit breaker unit life test is stopped in time, which can save test time and improve test efficiency.

[0014] In some implementations, when a battery pack fails, the cycle is stopped. This makes the test results more reliable and avoids continuing invalid tests.

[0015] In some implementations, a fault notification is received from the battery pack, and the battery pack is determined to have a fault according to the fault notification. In this way, the specific fault situation can be learned by analyzing the fault notification, and corresponding actions can be taken according to different fault situations.

[0016] In some implementations, when a battery pack fails, the load simulation circuit is notified to disconnect. Because the electrochemical reaction in the battery pack may be dangerous, timely notification of the load simulation circuit disconnection can protect the safety of the load simulation circuit and avoid the impact of the battery pack failure. In addition, timely notification of the load simulation circuit disconnection also protects the safety of the tester and avoids personal injury to the tester.

[0017] In some implementations, the high voltage action includes: turning on the battery pack disconnect unit so that the current of the battery pack can flow to the load simulation circuit through the battery pack disconnect unit and accumulate in the load simulation circuit. Because the high voltage conducts the battery pack and the load simulation circuit, the load simulation circuit can absorb the power of the battery pack, simulating the actual use scenario of the battery pack.

[0018] In some implementations, the high voltage lowering action includes: disconnecting the battery pack disconnecting unit so that the current of the battery pack cannot flow to the load simulation circuit. Because the high voltage lowering will disconnect the battery pack from the load simulation circuit, the load simulation circuit can release the absorbed electric energy through the simulated load so that the battery pack electric energy can be normally absorbed when the next cycle is turned on.

[0019] In some implementations, the notification uses a message of a controller area network bus protocol or a local area network bus protocol.

[0020] In the second aspect, the present application proposes a test device for a method of measuring the life of a battery pack circuit breaker unit, wherein the battery pack circuit breaker unit belongs to the battery pack. The test device includes: a notification unit for notifying the battery pack and a load simulation circuit, wherein the load simulation circuit performs a charge and a discharge; a central processing unit for controlling the notification unit to perform a notification action cyclically; a counter for counting the number of cycles; wherein the central processing unit is also used to determine the life of the battery pack circuit breaker unit according to the number of cycles.

[0021] According to some embodiments, the testing device further includes a receiving unit, etc., for implementing various implementations of the first aspect.

[0022] In a third aspect, the present application proposes a method for testing the life of a battery pack circuit breaker unit, wherein the battery pack circuit breaker unit belongs to the battery pack. The method comprises:

[0023] Receive a notification that the load simulation circuit performs one charge and one discharge, wherein when the load simulation circuit is charged, the current flows to the load simulation circuit through the battery pack disconnect unit; when the load simulation circuit is discharged, the electric energy is consumed in the load simulation circuit. According to the notification of charging and discharging, respectively control the battery pack disconnect unit to be turned on and off, so that when the load simulation circuit performs charging, the current flows from the battery pack to the load simulation circuit and accumulates in the load simulation circuit; when the load simulation circuit performs discharging, the electric energy is consumed in the load simulation circuit; perform the charging and discharging once; and according to the notification of cyclically performing charging and discharging, cyclically control the battery pack disconnect unit to be turned on and off to perform charging and discharging actions. This test method corresponds to the method of the first aspect, and when the execution subject is a battery pack, receives a notification from the test device that the load simulation circuit performs one charge and one discharge. And accordingly, the corresponding battery pack disconnect unit is turned on and off.

[0024] In a fourth aspect, the present application proposes a battery pack, including a battery management system, for receiving a notification to perform a charge and a discharge; performing a charge and a discharge, wherein, when charging, a battery pack disconnecting unit is turned on, so that the current of the battery pack flows to the load simulation circuit through the battery pack disconnecting unit and accumulates in the load simulation circuit; when discharging, the battery pack disconnecting unit is disconnected, so that the current of the battery pack cannot flow to the load simulation circuit; and according to the notification to perform the charge and discharge cyclically, the charge and discharge actions are cyclically performed.

[0025] The present application proposes a method for testing the life of a battery pack circuit breaker unit, controlling the battery pack circuit breaker unit to perform charging and discharging in a cycle, thereby realizing the testing of the life of the entire battery pack circuit breaker unit. The present application embodiment can measure the life of multiple high-voltage components in the battery pack circuit breaker unit at one time, with higher test efficiency, which is more in line with the situation of electric vehicles in real scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the drawings without paying creative work.

[0027] Figure 1 A schematic diagram of a battery pack circuit breaker unit testing system according to an embodiment of the present application is shown;

[0028] Figure 2A A flow chart showing a method for testing a battery pack circuit breaker unit according to an embodiment of the present application is shown;

[0029] Figure 2B A signaling diagram of a battery pack circuit breaker unit testing method according to an embodiment of the present application is shown;

[0030] Figure 3A A flow chart showing a charging and discharging method according to an embodiment of the present application is shown;

[0031] Figure 3B A signaling diagram of a charging and discharging method according to an embodiment of the present application is shown;

[0032] Figure 4A A flowchart showing a fault handling method according to an embodiment of the present application is shown;

[0033] Figure 4B A signaling diagram of a fault handling method according to an embodiment of the present application is shown;

[0034] Figure 5 A flow chart showing a method for testing a battery pack circuit breaker unit according to another embodiment of the present application is shown;

[0035] Figure 6 A schematic diagram of a testing device according to an embodiment of the present application is shown;

[0036] Fig. 7A A schematic diagram showing a battery pack disconnecting unit in an embodiment of the present application in a conducting state;

[0037] Figure 7B A schematic diagram showing a battery pack disconnecting unit in a disconnected state according to an embodiment of the present application is shown;

[0038] Fig. 8A A schematic diagram showing a load simulation circuit in an embodiment of the present application when charging is shown;

[0039] Figure 8B A schematic diagram showing a load simulation circuit in an embodiment of the present application during discharge is shown;

[0040] Figure 8C A schematic diagram showing a load simulation circuit in an embodiment of the present application when it is disconnected;

[0041] Fig.8D A schematic diagram showing a load simulation circuit disconnected according to another embodiment of the present application is shown. DETAILED DESCRIPTION

[0042] The following detailed description and drawings of the embodiments of the present application are used to illustrate the principles of the present application, but cannot be used to limit the scope of the present application, that is, the present application is not limited to the described embodiments.

[0043] In the description of the present application, it should be noted that, unless otherwise specified, “plurality” means more than two; in addition, the terms “first”, “second”, “third”, etc. are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0044] like Figure 1 As shown, the present application discloses an innovative test device 300 for controlling the life test of the entire battery pack circuit breaker unit 110. The test device 300 is responsible for controlling the battery pack 100 and the load simulation circuit 200 so that the load simulation circuit 200 performs charging and discharging. The battery pack circuit breaker unit 110 is electrically connected to the load simulation circuit 200. Specifically, one side of the battery pack circuit breaker unit 110 is electrically connected to the total positive and total negative electricity in the battery pack 100, and the other side is electrically connected to the positive and negative electrodes of the load simulation circuit 200.

[0045] The battery pack 100 generally includes a number of battery cells 120, a battery pack disconnecting unit 110 and a battery management system 130. The battery pack disconnecting unit 110 is connected to the total positive and total negative of the battery cells 120. The battery cell 120 includes a positive electrode sheet, a negative electrode sheet, a separator and an electrolyte. The types of battery cells 120 may include lithium-ion batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries or magnesium-ion batteries, etc., which are not limited in the embodiments of the present application. The battery management system 130 is the "brain" of the battery pack 100, which communicates with the battery cells 120 and mainly collects and monitors the voltage, current, temperature and other data of the battery system to realize battery status monitoring and analysis, battery safety protection, power control management and information management. The battery management system 130 is generally physically located independently in the battery pack 100. The battery management system 130 also communicates with the battery pack disconnecting unit 110 to control the latter's closing or disconnection to conduct or disconnect the current between the battery system and the electric drive system.

[0046] The load simulation circuit 200 is used to simulate the load of the electric vehicle in the life test, that is, the electric drive system to make the test process close to the actual use of the electric vehicle. For the sake of simplicity, the load simulation circuit 200 of the present application is mainly used to simulate the motor. The load simulation circuit 200 can have two connection ports, which are used to connect the positive and negative poles of the battery pack circuit breaker unit 110 respectively. The details of the load simulation circuit 200 will be described below.

[0047] The battery pack circuit breaker unit 110 can be considered as a connection point between a battery pack and a load. The battery pack circuit breaker unit 110, also known as a high-voltage distribution box or a battery disconnection unit, is responsible for the on-off of the current between the battery system and the electric drive system. The battery pack circuit breaker unit 110 generally includes multiple components, such as resistors, relays, etc. Physically, the battery pack circuit breaker unit 110 is generally integrated in the battery pack 100. In order to evaluate whether the battery pack circuit breaker unit 110 meets the requirements of the number of times or years of use of the battery pack, the life of the internal battery pack circuit breaker unit 110 is generally tested before the battery pack 100 leaves the factory. The usual practice is to use a load simulation circuit 200 to simulate the electric drive system.

[0048] The traditional test method only involves the battery pack and the load simulation circuit. During the test, the load simulation circuit is manually controlled to be turned on or off to achieve the purpose of life test. And it can only test the life of a single component in the battery pack circuit breaker unit 110, such as a resistor. That is, the traditional test method cannot test the life of all components in the battery pack circuit breaker unit. The traditional test efficiency is low and does not match the actual working conditions of the vehicle.

[0049] Compared with the traditional test method, the test method of the present application realizes test automation. In addition, the test method of the present application is more efficient, more reliable, and has more accurate test results, because the test method of the present application can test the life of the entire battery pack circuit breaker unit 110 at one time, that is, the life of all high-voltage components in the battery pack circuit breaker unit 110.

[0050] like Figure 2A or Figure 2B As shown, the embodiment of the present application provides a method for measuring the life of a battery pack disconnecting unit, wherein the battery pack disconnecting unit 110 belongs to the battery pack 100. The method includes the following actions:

[0051] S100: Notify the battery pack 100 and the load simulation circuit 200, and the load simulation circuit 200 performs a charge and a discharge. When the load simulation circuit 200 performs charging, the current flows from the battery pack 100 to the load simulation circuit 200 and accumulates in the load simulation circuit 200; when the load simulation circuit 200 performs discharging, the electric energy is consumed in the load simulation circuit 200.

[0052] One side of the battery pack disconnection unit 110 includes two interfaces respectively connected to the total positive and negative electrodes of the battery cells 120. The other side of the battery pack disconnection unit 110 includes two interfaces as the total interface of the battery pack 100, which are used to electrically connect to the positive and negative electrodes of the load simulation circuit 200 respectively.

[0053] Notifying the battery pack 100 to perform a charge and discharge specifically includes notifying the battery management system 130 in the battery pack 100. Then, the battery management system 130 controls the conduction and disconnection of the battery pack circuit breaker unit 110. The notification can be a message signal or a combination of a message signal and a level signal. A level signal refers to a signal represented by a level value, and the level value is divided into a high level "1" and a low level value "0", corresponding to a high level signal and a low level signal, respectively. In some embodiments, the sending entity of the notification can be a test device 300, and the test device 300 is specifically described below.

[0054] Charging means that the battery pack disconnecting unit 110 of the battery pack 100 is turned on. The load simulation circuit is switched to a charging state. The current of the battery cells 120 in the battery pack 100 can flow to the load simulation circuit 200 through the battery pack disconnecting unit 110 and accumulate in the load simulation circuit 200. It can also be said that the load simulation circuit 200 absorbs electrical energy.

[0055] Discharging means that the battery pack disconnecting unit 110 of the battery pack 100 is disconnected. The load simulation circuit is switched to a discharge state. The electric energy of the battery cells 120 in the battery pack 100 cannot flow to the load simulation circuit 200 through the battery pack disconnecting unit 110. The electric energy absorbed by the load simulation circuit 200 during charging can be consumed during the discharge process.

[0056] Accumulation in the load simulation circuit 200 means that the current flowing out of the battery pack 100 flows into the load simulation circuit 200, and the electrical energy brought by the current is converted into other forms of energy and stored through components in the circuit.

[0057] Consumption refers to the load simulation circuit 200, which converts electrical energy into other energy sources, such as heat energy or mechanical energy, through components in the circuit during the above-mentioned discharge process. The load simulation circuit 200 consumes electrical energy by dissipating heat energy to the outside air through heat transfer or releasing mechanical energy in the form of work.

[0058] In some embodiments, the notification of step S100 to the battery pack circuit breaker unit 110 and the load simulation circuit 200 to perform a discharge includes: after the notification of performing a charging action in step S100 is issued, a notification to perform a discharge is issued after waiting for a first time period, or when the voltage of the load simulation circuit 200 reaches a voltage threshold.

[0059] The first time period can be set according to the time required for the load simulation circuit 200 to complete charging. The time required for the load simulation circuit 200 to complete charging varies according to factors such as the capacity, chemical materials, and temperature of the battery pack 100. The first time period should be greater than or equal to the time required for the load simulation circuit 200 to complete charging. Exemplarily, the first time period can be 1s, 2s, 3s, 4s, or 5s, etc. Those skilled in the art often regard the first time period as the time required for the battery pack 100 to complete the high-voltage action from receiving the upper high-voltage signal.

[0060] The voltage threshold can be set according to the rated voltage of the battery pack 100. For example, the voltage threshold can be set to 50%, 60% or 80% of the rated voltage. The voltage threshold can be one of 8V, 9V, 10V, 11V, 12V, preferably 10V. The rated voltage refers to the voltage difference between the total positive electrode and the total negative electrode of the battery pack. As the load simulation circuit 200 performs charging, the voltage of the load simulation circuit 200 gradually rises. When it rises to a certain level, it indicates that the charging is completed.

[0061] S200: Execute the notification action S100 in a loop.

[0062] In this embodiment, the cyclic execution means executing S100 multiple times, that is, notifying the battery pack 100 and the load simulation circuit 200 multiple times to perform one charge and discharge. When one charge and discharge is completed, the next charge and discharge is continued according to a certain procedure.

[0063] The loop execution of S100 includes, after the notification of executing a discharge action in step S100 is issued, waiting for a second time period, and then loop execution of S100.

[0064] The second time period can be set according to the time required for the load simulation circuit 200 to complete the discharge. The time required for the load simulation circuit 200 to complete the discharge varies according to factors such as the capacity, chemical materials, and temperature of the battery pack 100 it simulates. The second time period should be greater than or equal to the time required for the load simulation circuit 200 to complete the discharge. Exemplarily, the second time period may include 3s, 4s, and 5s. From another perspective, the second time period can also be considered as the time from when the battery pack 100 receives the lower high voltage signal until the lower high voltage action is completed.

[0065] In some embodiments, the cyclic execution of S100 further includes: when the number of cycles of step S200 reaches the life threshold, stop step S200. The life threshold can be the number of times the electric vehicle is started or stopped, or the service life of the electric vehicle. The latter is generally calculated based on the former. For example, according to user needs, the battery pack circuit breaker unit 110 is required to be used 5000 times. When the number of notifications for cyclic execution reaches 5000 times, the service life requirements of the battery pack circuit breaker unit 110 have been met. At this time, there is no need to continue testing the maximum number of cycles of the battery pack circuit breaker unit 110 of the battery pack 100, and the test can be stopped. When the service life of the battery pack circuit breaker unit is measured by the service life of the electric vehicle, those skilled in the art can convert the number of cycles into years. For example, the life of the battery pack circuit breaker unit = number of cycles / estimated number of starts or stops of the electric vehicle per day / 365 days, wherein the unit of the life of the battery pack circuit breaker unit is year, and the estimated number of starts or stops of the electric vehicle per day can be 8 times, 9 times, 10 times, preferably 10 times.

[0066] Optionally, or alternatively, the cyclic execution of S100 also includes: when the battery pack circuit breaker unit 110 fails, stop step S200. Depending on the situation, the load simulation circuit 200 may be disconnected to ensure the safety of the tester. The fault may include damage to the components of the battery pack circuit breaker unit 110, resulting in a short circuit or open circuit in the battery pack circuit breaker unit 110. These faults may cause the battery pack circuit breaker unit 110 to be unable to continue to perform the upper high voltage or lower high voltage action. When the battery management system 130 detects that the battery pack circuit breaker unit 110 has a fault, it notifies the test device 300. In some embodiments, the fault can be divided into multiple levels. For example, according to the severity of the fault from low to high, the fault level is divided into level 1, level 2 and level 3. The hysteresis of the battery pack circuit breaker unit 110 turning on and off can be set to level 1. The test can still continue under hysteresis, but the test time becomes longer. There is no need to stop the test in case of level 1 fault. Level 2 and level 3 can include short circuit and open circuit of the battery pack circuit breaker unit 110, respectively. The battery pack disconnection unit 110 is short-circuited, so that the electric energy of the load simulation capacitor 220 cannot be released. The battery pack disconnection unit 110 is disconnected, so that the electric energy of the battery pack 100 cannot be transmitted to the load simulation circuit 200. The latter two faults will make the test impossible.

[0067] Stop means that the test device 300 no longer sends the step S100 notification to the battery pack 100 and the load simulation circuit 200. The battery pack 100 and the load simulation circuit 200 no longer perform charging and discharging. The conditions for stopping the cycle include two situations: the number of cycle execution notifications reaches the life threshold, or the battery pack 100 has the aforementioned fault.

[0068] S300: Determine the life of the battery pack disconnecting unit 110 according to the number of cycles.

[0069] The number of cycles refers to the number of times the battery pack disconnection unit 110 and the load simulation circuit 200 are notified to perform one charge and discharge. The counting of the number of cycles can be performed by the test device 300 and stored in the memory 390.

[0070] When the life span refers to the number of times the electric vehicle is started or stopped, the above number of cycles is its life span value. In other words, determining the life span of the battery pack disconnecting unit 110 means determining how many times the battery pack disconnecting unit 110 can perform charging and discharging. When the life span refers to the service life, the life span can be obtained by converting the number of cycles into years according to the above formula.

[0071] The battery pack circuit breaker unit 110 and the load simulation circuit 200 perform charging and discharging in a cycle. According to the number of cycles, the life of all high-voltage components in the battery pack circuit breaker unit can be obtained. The test efficiency is higher and more in line with the actual working conditions of electric vehicles.

[0072] like Figure 3Aor Figure 3B As shown, in some embodiments, the action of step S100 notifying the battery pack 100 and the load simulation circuit 200 to perform a charge may include the following actions:

[0073] S110 : sending a high-voltage signal to the battery pack 100 to enable the battery pack disconnecting unit 110 to perform a high-voltage action.

[0074] The high voltage action refers to the battery pack disconnect unit 110 switching to the on state. The battery pack 100 battery cell 120 outputs high voltage electricity to the load simulation circuit 200. Specifically, the components in the battery pack disconnect unit 110, such as relays, can be opened or closed in a certain order. The specific opening and closing order is described in detail below.

[0075] The upper high voltage signal may be a message signal. The sending subject of the upper high voltage signal may be the test device 300, and the receiving subject may be the battery management system 130 of the battery pack 100. After receiving the upper high voltage signal, the battery management system 130 controls the battery pack disconnecting unit 110 to perform the upper high voltage action.

[0076] S120 : Sending a charging signal to the load simulation circuit 200 , so that the load simulation circuit 200 absorbs electrical energy from the battery pack 100 .

[0077] The charging signal may be a level signal or a message signal. The sending subject of the charging signal may be the test device 300. When the charging signal is a level signal, the receiving subject may be the corresponding relay 210 of the load simulation circuit 200. The corresponding relay 210 is closed or opened according to the level signal. When the charging signal is a message signal, the receiving subject may be the processor of the load simulation circuit 200. The processor parses the message signal and controls the corresponding relay 210 to be closed or opened.

[0078] The execution order of the above S110 and S120 is not limited, and can be parallel or serial.

[0079] like Figure 3A or Figure 3B As shown, in step S100, notifying the battery pack 100 and the load simulation circuit 200 to perform a discharge may include the following actions S130 and S140, specifically:

[0080] S130: Sending a low-voltage signal to the battery pack 100 so that the battery pack disconnecting unit 110 performs a low-voltage action.

[0081] The lower high voltage signal may be a message signal. In this embodiment, the sending subject of the lower high voltage signal may be the test device 300, and the receiving subject may be the battery pack 100, such as the battery management system 130 of the battery pack 100. After receiving the lower high voltage signal, the battery management system 130 controls the battery pack disconnect unit 110 to perform the lower high voltage action.

[0082] The lower high voltage action refers to the battery pack disconnecting unit 110 switching to the disconnected state. The electrical connection between the battery pack 100 and the load simulation circuit 200 is disconnected. Specifically, the components in the battery pack disconnecting unit 110, such as relays, are disconnected in a certain order. The specific disconnection order is described below.

[0083] S140: Sending a discharge signal to the load simulation circuit 200 to enable the load simulation circuit 200 to release the absorbed electrical energy.

[0084] The discharge signal may be a message signal or a level signal. The sending subject of the discharge signal may be the test device 300. When the discharge signal is a message signal, the receiving subject is the processor of the load simulation circuit 200. After the processor parses the message signal, it controls the corresponding relay 210 to close or open. When the charging signal is a level signal, the receiving subject is the corresponding relay 210 of the load simulation circuit 200. The corresponding relay 210 is closed or opened after receiving the level signal.

[0085] The execution order of the above actions S130 and S140 is not limited and can be performed in parallel or in series.

[0086] like Figure 4A or Figure 4B As shown, in some embodiments, when the battery pack disconnecting unit 110 fails, in order to identify the fault level and notify the load simulation circuit 200 to disconnect, the battery pack disconnecting unit 110 life test method may further include the following actions:

[0087] S410: Receive a fault notification from the battery pack 100. The receiving subject is the test device 300. The receiving object is the battery management system 130 of the battery pack 100. The fault notification may be a message signal.

[0088] S420: Determine that the battery pack 100 has failed. Determine that the battery pack 100 has failed means that the test device 300 analyzes the fault notification and obtains the fault level. As mentioned above, according to the severity of the fault from low to high, the fault level can be divided into three levels: level 1, level 2 and level 3.

[0089] S430: When the fault level is high, such as level 2 and level 3, the load simulation circuit 200 is notified to disconnect. The execution subject of the notification is the test device 300. The notification can be a message signal or a level signal. Notifying the load simulation circuit 200 to disconnect includes notifying it to disconnect different components according to different fault levels, such as opening different relays. The specific content is described in detail below. This can end or terminate the test.

[0090] The present application also proposes another testing method for testing the life of the battery pack disconnecting unit 110 of the battery pack 100. The execution subject of the battery pack disconnecting unit 110 life testing method is the load simulation circuit 200, which corresponds to the steps in FIG. 2, FIG. 3 and FIG. 4 where the execution subject is the testing device 300. Figure 5 As shown, the test method includes:

[0091] S500: receiving a notification that the load simulation circuit 200 performs one charge and discharge.

[0092] Step S500 corresponds to step S100 , and the battery pack 100 receives the notification of the load simulation circuit 200 performing charging and discharging. Specifically, the receiving subject may be the battery management system 130 .

[0093] S510: According to the notification of charging and discharging, the battery pack circuit breaker unit 110 is controlled to be turned on and off respectively, so that when the load simulation circuit 200 is performing charging, the current flows from the battery pack 100 to the load simulation circuit 200 and accumulates in the load simulation circuit 200; when the load simulation circuit 200 is performing discharging, the electric energy is consumed in the load simulation circuit 200.

[0094] In some embodiments of the present application, respectively controlling the battery pack disconnecting unit 110 to be turned on and off means that, according to the notification of charging, the battery pack disconnecting unit 110 is controlled to be switched to a turned-on state according to the upper high voltage action, so that current flows from the battery pack 100 to the load simulation circuit 200 and accumulates in the load simulation circuit 200. And according to the notification of discharging, the battery pack disconnecting unit 110 is controlled to be switched to a turned-off state according to the lower high voltage action, so that current cannot flow from the battery pack 100 to the load simulation circuit 200.

[0095] S520: According to the notification of cyclically performing charging and discharging, the battery pack disconnecting unit 110 is cyclically controlled to be turned on and off.

[0096] After the battery pack 100 completes the second time period of the discharge action, the test device 300 sends out the charging and discharging notification again, and the battery pack 100 receives the charging and discharging notification again and performs the charging and discharging actions. The time corresponding to the charging action is consistent with the time of the upper high voltage action in the aforementioned embodiment, and the time corresponding to the discharging action is consistent with the time of the lower high voltage action in the aforementioned embodiment.

[0097] like Figure 6 As shown, the present application proposes a testing device 300 for testing the life of the battery pack disconnecting unit 110 of the battery pack 100. Figure 1 The test device 300 is shown to communicate with the battery pack 100 and the load simulation circuit 200. The test device 300 includes: a notification unit 310, which is used to notify the battery pack 100 to perform a charge and discharge; a central processing unit 380, which is used to control the notification unit 310 to perform the notification action cyclically; a counter 320, which is used to count the number of multiple cycles; and the central processing unit 380 is also used to determine the life of the battery pack circuit breaker unit according to the number of cycles.

[0098] Specifically, the notification unit 310 is used to notify the battery pack 100 of the high voltage signal, and to notify the load simulation circuit 200 to execute the charging signal. The notification unit 310 is also used to notify the battery pack 100 of the low voltage signal, and to notify the load simulation circuit 200 to execute the discharging signal. In some embodiments, the notification unit 310 is also used to send a fault notification to the load simulation circuit 200.

[0099] In some embodiments, the CPU 380 is further configured to obtain the number of cycles from the counting unit 320. When the life is represented by the number of cycles, the CPU 380 directly uses the number of cycles. When the life is represented by the years of use, as above, the CPU 380 calculates the years of use based on the number of cycles. The test device 300 also includes a display unit 340 for displaying the life in a visual manner so that the tester can know the life value.

[0100] In some embodiments, the test device 300 further includes a receiving unit 330 for receiving a fault notification from the battery pack 100. Accordingly, the central processor 380 is also used to determine the fault level of the battery pack 100 and instruct the notification unit 310 to send a fault notification to the load simulation circuit 200 as appropriate.

[0101] In some embodiments, the test device 300 also includes an alarm unit 350, which is used to control the alarm unit 350 to alarm when a test fault is found in the central processor 380. The test fault may be the above-mentioned fault of the battery pack circuit breaker unit 110, the failure of the components of the load simulation circuit 200, the disconnection of the connection between the battery pack 100 and the load simulation circuit 200, or the failure of the battery cell 120, and the battery management system 130 loses response. At this time, the alarm unit 350 can sound an alarm. The alarm form includes but is not limited to flashing indicator lights and sound alarms. On-site testers can be informed of other fault types through the alarm. At this time, test steps S100 to S300 will be terminated. Wait for the on-site tester to repair the fault, and the test will continue after the repair is completed.

[0102] The test device 300 also includes a memory 390. The memory 390 may include a large capacity memory for data or instructions. By way of example and not limitation, the memory 390 may include a hard disk drive (HDD), a floppy disk drive, a flash memory, an optical disk, a magneto-optical disk, a tape, or a universal serial bus (USB) drive or a combination of two or more of these. In some instances, the memory 390 may include a removable or non-removable medium, or the memory is a non-volatile solid-state memory. In some embodiments, the memory 390 may be inside or outside the battery pack 100. In some instances, the memory 390 may be a read-only memory (ROM). In one instance, the ROM may be a mask-programmed ROM, a programmable ROM (PROM), an erasable PROM (EPROM), an electrically erasable PROM (EEPROM), an electrically rewritable ROM (EAROM) or a flash memory or a combination of two or more of these. The memory 390 may include a read-only memory (ROM), a random access memory (RAM), a disk storage medium device, an optical storage medium device, a flash memory device, an electrical, optical or other physical / tangible memory storage device. Therefore, the memory 390 includes one or more tangible computer-readable storage media encoded with software including computer-executable instructions, and when the software is executed, it is operable to perform the operations described with reference to the method according to one aspect of the present disclosure. The memory 390 stores the control program of the above-mentioned battery pack circuit breaker unit 110 life test method, which is executed by the notification unit 310, the central processing unit 380, the counting unit 320, the alarm unit 350, the receiving unit 330 and the display unit 340 respectively. The control program includes message information and level information, as well as counting information of the number of notification cycles. It also includes fault information, which includes the fault notification to be sent when receiving fault information from the battery management system 130. The central processing unit 380 reads and executes the computer program instructions stored in the memory 390 to implement Figures 2 to 3. Figure 5 The method / steps in the embodiment shown in FIG. 2 to FIG. Figure 5 The example shown executes the method / steps to achieve the corresponding technical effects, and the specific execution methods / steps of the embodiments are as described above.

[0103] Based on the same inventive concept, the present application proposes an innovative battery pack, including a battery management system 130 . The battery management system 130 is used to communicate with a testing device 300 .

[0104] The battery management system 130 is used to collect, process, and store information such as the voltage and current of the battery cells 120 and the battery pack disconnecting unit 110 during use of the battery pack 100, and send it to the testing device 300. The voltage information may include the voltage across the battery pack disconnecting unit 110, and / or the voltage across the components inside the battery pack disconnecting unit 110, for example, the voltage across the main negative relay 114 or the voltage across the pre-charge relay 112.

[0105] The battery management system 130 includes a communication module for receiving the charging and discharging notifications from the test device in the aforementioned embodiment. The battery management system 130 also includes a controller for controlling the battery pack disconnect unit 110 to perform the corresponding received charging or discharging action based on the charging and discharging notifications. When performing a charging action, the controller of the battery management system 130 controls the corresponding relay of the battery pack disconnect unit 110 to close to realize the conduction of the battery pack disconnect unit 110. When performing a discharging action, the controller of the battery management system 130 controls the corresponding relay of the battery pack disconnect unit 110 to disconnect to realize the conduction of the battery pack disconnect unit 110.

[0106] The communication module of the battery management system 130 is also used to receive a cycle notification from the test device 300. Accordingly, the controller of the battery management system 130 controls the battery pack disconnecting unit 110 to perform charging and discharging in a cycle.

[0107] The communication module of the battery management system 130 is also used to send the aforementioned fault notification to the test device 300 when a fault occurs in the battery pack disconnect unit 110. Accordingly, the controller of the battery management system 130 is also used for fault identification, and is used to identify the fault level according to a certain frequency. The controller of the battery management system 130 can identify the fault level based on information such as the voltage value at both ends of the component or the time to execute closing or disconnection. For example, when a component of the battery pack disconnect unit 110 is short-circuited, the voltages at both ends will be the same and equal to the total voltage. When a circuit is broken, the voltage at one end will be 0. When hysteresis occurs, the voltage change time of the relay where the hysteresis occurs is significantly different from the time when the battery management system 130 receives the notification. When the controller of the battery management system 130 identifies different fault levels, the communication module is also used to send a fault notification carrying specific fault level information to the test device 300.

[0108] As is well known to those skilled in the art, the battery management system 130 is generally a printed circuit board (PCB), wherein the communication module and the controller are integrated circuits or components soldered on the PCB.

[0109] The test method of the embodiment of the present application can be applied to any structure of the battery pack disconnecting unit. It is only used to explain the on and off process and principle of the battery pack disconnecting unit. The components and their connection relationships in the battery pack disconnecting unit can be referred to Fig. 7A and 7B .

[0110] The battery pack disconnect unit 110 may include a main positive relay 111 and a main negative relay 114. The main positive relay 111 is connected to the total positive pole of several battery cells 120. The main negative relay 114 is connected to the total negative pole of several battery cells 120. The main positive relay 111 and the main negative relay 114 are used to disconnect / conduct the electrical connection with the total positive pole and the total negative pole, respectively. A relay is an electric switch. When the voltage and current input reach a threshold, the relay opens or closes. The main positive relay 111 and the main negative relay 114 can be any type of existing relay, such as an electromagnetic relay, a time relay, a thermal relay, etc. The main positive relay 111 and the main negative relay 114 should be high-voltage components that can withstand the high voltage of the total positive pole and the total negative pole. Depending on the design requirements of the battery pack, sometimes the voltage of the total positive pole and the total negative pole can reach up to 1000V.

[0111] Optionally, the battery pack disconnect unit 110 also includes a pre-charging circuit. The pre-charging circuit plays a role in limiting the charging current of the capacitor when the power is turned on, so as to protect the components in the load simulation circuit 200, such as capacitors, from being damaged by the instantaneous large current. The pre-charging circuit is connected in parallel with the main positive relay 111. The pre-charging circuit may include a pre-charging relay 112 and a pre-charging resistor 113. The two are connected in series and are also high-voltage components.

[0112] The high voltage action generally includes first disconnecting the main positive relay 111, conducting the pre-charge circuit and the main negative relay 114. Then, the main positive and main negative relays 114 are turned on, and the pre-charge circuit is disconnected. For example, the high voltage action includes first closing the pre-charge relay 112 and the main negative relay 114, opening the main positive relay 111 (not shown in the figure), and then closing the main positive relay 111 and the main negative relay 114, disconnecting the pre-charge relay 112 (such as Fig. 7AAs shown). When the pre-charging circuit is turned on first, the load simulation circuit 200 is pre-charged. At this time, because the current flows through the pre-charging resistor 113, the voltage is lower than the voltage when it only flows through the main positive relay 111. At this time. The battery cell 120, the battery pack disconnect unit 110 and the load simulation circuit 200 form a current loop. Specifically, the current flows from the total positive electrode of several battery cells 120, through the pre-charging circuit of the battery pack disconnect unit 110, to the load simulation circuit 200, and then flows through the main negative relay 114 back to the total negative electrode of several battery cells 120. In this process, the current will accumulate in the load simulation circuit 200. After a period of pre-charging, regular charging is entered until the load simulation circuit 200 is fully charged.

[0113] like Fig. 7A As shown, when the load simulation circuit 200 performs charging, the battery pack disconnect unit 110 is in a conducting state. Specifically, the main positive relay 111 and the main negative relay 114 are closed, and the pre-charge relay 112 is open. At this time, the battery cells 120, the battery pack disconnect unit 110 and the load simulation circuit 200 still form a current loop. Specifically, the current flows from the total positive electrode of several battery cells 120, through the main positive relay 111 of the battery pack disconnect unit 110, to the load simulation circuit 200, and then through the main negative relay 114 back to the total negative electrode of several battery cells 120.

[0114] The high voltage action generally includes disconnecting the main positive relay 111, the main negative relay 114 and the pre-charging circuit. Cutting off the high voltage output of the battery cell 120 to the load simulation circuit 200. When the load simulation circuit 200 performs discharge, the battery pack disconnection unit 110 is in the disconnected state. Specifically, Figure 7B As shown, the main positive relay 111 and the main negative relay 114 are open, and the pre-charge relay 112 is also open. At this time, the current loop between the battery cell 120, the battery pack disconnecting unit 110 and the load simulation circuit 200 is disconnected.

[0115] In some embodiments, the voltage of the load simulation circuit 200 can be represented by the voltage difference across the main positive relay 111. Accordingly, the battery management system 130 can obtain the voltage difference across the main positive relay 111 at a certain period. Then, the battery management system 130 sends the voltage difference to the test device 300 at a certain period. The period can include 100ms, 150ms, 200ms, preferably 100ms.

[0116] In some embodiments, the short circuit of the battery pack disconnect unit 110 may include the main positive relay 111 , the main negative relay 114 , and the pre-charge relay 112 being stuck.

[0117] In some embodiments, the battery pack disconnecting unit 110 may further include a voltmeter for measuring the voltage across different components of the battery pack disconnecting unit 110. Accordingly, the battery management system 130 may obtain the voltage value of the voltmeter to identify component failures in the battery pack disconnecting unit 110.

[0118] It is only used to explain the charging and discharging process of the load simulation circuit 200. Fig. 8A or Figure 8B An example of a load simulation circuit 200 is provided. Those skilled in the art can understand that the testing method of the embodiment of the present application can be applied to any load simulation circuit.

[0119] like Fig. 8A As shown, the load simulation circuit 200 includes a processor 240, a load simulation capacitor 220, a first relay 210, a discharge resistor 230, and a second relay 250. The first relay 210 is connected in series with the discharge resistor 230 and the load simulation capacitor 220. Among them, the first relay 210 is used to turn on or off the electrical connection between the discharge resistor 230 and the load simulation capacitor 220. The second relay 250 is connected in series with the circuit composed of the other three, and serves as the main switch of the load simulation circuit 200, which is used to turn on or off the electrical connection between the load simulation circuit 200 and the battery pack 100.

[0120] The load simulation circuit 200 includes a processor 240, which is used to receive the above charging and discharging notifications, such as messages, and control the conduction and closing of corresponding relays to implement the load simulation circuit 200 to switch between the charging state and the discharging state.

[0121] In some embodiments, during the charging and discharging actions, the first relay 210 may be a relay with a longer life and more durable because it needs to be repeatedly opened and closed. When the load simulation circuit 200 receives the fault notification, the relay that needs to be disconnected is the second relay 250. Since the second relay 250 needs to be disconnected immediately when a fault occurs, the second relay 250 may be a sensitive relay. The first relay 210 and the second relay 250 may be a normally open relay or a normally closed relay. In some embodiments, when the fault notification is a low level signal, the second relay 250 receiving the level signal may be a normally open relay. When the fault notification is a high level signal, the second relay 250 is a normally closed relay, and the level signal is a low level signal. The first relay 210 and the second relay 250 include but are not limited to electromagnetic relays, induction relays, electric relays, and electronic relays, and can implement the technical solution of the present application. From another perspective, the first relay 210 and the second relay 250 may be high-power relays.

[0122] Preferably, the load simulation capacitor 220 can be a safety capacitor. After the safety capacitor fails, it will not cause the capacitor to break down, and will not endanger the personal safety of the test site personnel. Further preferably, the safety capacitor can be a capacitor for suppressing electromagnetic interference of the power supply. The capacitor for suppressing electromagnetic interference of the power supply has a large volume, allows a large current for instantaneous charging and discharging, and has a correspondingly small internal resistance and good charging stability. It can simulate the drive motor, on-board charger, electric compressor, etc. in actual use of electric vehicles.

[0123] Charging the load simulation circuit 200 can be considered as charging the load simulation capacitor 220 in the load simulation circuit 200. Capacitor charging means that after the capacitor is connected to the power supply, current flows from the power supply to the capacitor and accumulates in the capacitor. The charging process of the capacitor is completed until no current flows between the power supply and the capacitor. Specifically in the present application, after the load simulation capacitor 220 is connected to the battery pack 100, current flows from the battery pack 100 to the load simulation capacitor 220, and electricity is accumulated in the load simulation capacitor 220. Fig. 8A As shown, when a charging notification is received, the processor 240 controls the first relay 210 to close and the second relay 250 to open. At this time, the load simulation circuit 200 performs charging. The battery cell 120, the battery pack disconnect unit 110 and the load simulation circuit 200 form a current loop. The current flows from the total positive electrode of several battery cells 120, through the battery pack disconnect unit 110, to the load simulation circuit 200, and then returns to the total negative electrode of several battery cells 120. The load simulation capacitor 220 in the load simulation circuit 200 absorbs the electrical energy of the battery cell 120 for charging.

[0124] The discharge performed by the load simulation circuit 200 can be regarded as the discharge of the load simulation capacitor 220 in the load simulation circuit 200. Capacitor discharge refers to the capacitor converting the stored electrical energy into other forms of energy in the circuit by doing work through current, and the capacitor discharges through a resistor. The resistor converts electrical energy into other forms of energy. When the voltage between the two conductive parallel plates of the capacitor drops to a certain value, the discharge process of the capacitor is completed. The capacitor converts the stored electrical energy into other forms of energy in the circuit by doing work through current. Specifically for the present application, after cutting off the connection between the load simulation capacitor 220 and the battery pack 100, the load simulation capacitor 220 discharges through the discharge resistor 230. Figure 8BAs shown, when receiving the discharge notification, the processor 240 controls the first relay 210 and the second relay 250 to close. At this time, the load simulation circuit 200 performs discharge. The load simulation capacitor 220, the first relay 210 and the discharge resistor 230 form a current loop. The current flows from the load simulation capacitor 220 to the discharge resistor 230. The electric energy in the load simulation capacitor 220 is released through the discharge resistor 230. At this time, the electric energy of the battery cell 120 in the battery pack 100 cannot flow to the load simulation circuit 200 through the battery pack disconnect unit 110.

[0125] Preferably, the discharge resistor 230 may include an aluminum shell brake resistor. When the discharge resistor 230 is connected to the load simulation capacitor 220, the discharge resistor 230 can discharge the residual charge in the load simulation capacitor 220 within a certain period of time, such as 5 seconds, so that the voltage in the capacitor is quickly reduced to the target voltage, ensuring that the charging current of the load simulation capacitor 220 is close to the vehicle working condition.

[0126] The battery management system 130 notifies the load simulation circuit 200 of the fault through the test device 300. For different fault levels, the load simulation circuit 200 can be notified to take different processing actions. As mentioned above, when the fault notification is a message signal, the processor 240 is also used to receive and parse the above fault notification, and control the second relay 250 to disconnect, so as to protect the load simulation circuit 200. When the notification is a level signal, the recipient of the fault notification is the corresponding relay. The level signal causes the corresponding relay 250 to disconnect or open. For example, the short circuit fault of the battery pack disconnect unit 110 is set to level 3, the open circuit fault is set to level 2, and the hysteresis of the battery pack disconnect unit 110 is set to level 1. When the test device 300 determines that a level 3 fault occurs, a first fault notification is sent to the load simulation circuit 200. Notify the load simulation circuit 200 to close the first relay 210 and disconnect the second relay 250, such as Figure 8C As shown. This can disconnect the connection with the load simulation circuit 200 and release the electrical energy in the simulated load 220. This can ensure the safety of the tester and facilitate the tester to subsequently check or diagnose the load simulation circuit 200. When the test device 300 determines that a level 2 fault has occurred, a second fault notification is sent to the load simulation circuit 200. The load simulation circuit 200 is notified to disconnect the second relay 250. The first relay 210 can be closed or disconnected. As shown Fig.8D As shown, it is preferred to close the first relay 210. When the test device 300 determines that a level 1 fault occurs, a fault notification may not be sent to the load simulation circuit 110.

[0127] In some embodiments, the failure of components of the load simulation circuit 200 may also make the test impossible. For example, a relay in the load simulation circuit 200 is stuck, or the load simulation capacitor 220 is damaged and cannot be charged or discharged. At this time, the processor 240 will send an alarm signal and disconnect the load simulation circuit 200 from the battery pack 100. At this time, the test steps S100 to S300 will be terminated, and accordingly, the counting unit records the number of cycles. Wait for the on-site tester to repair the fault. After the repair is completed, the test continues.

[0128] In the above embodiments, electric vehicles are used as an example. For ordinary technicians in this field, the high-voltage circuit testing method and device can also be applied to energy storage systems. When applied to energy storage systems, the load simulated by the load simulation circuit 200 can be a power grid, an industrial backup power supply, a data center and a base station, and a household power load.

[0129] In some embodiments, the test device 300, the battery management system 130 and the processor 240 may also include a communication interface for realizing communication between the modules, devices, units and / or equipment in the embodiments of the present application. The communication interface may adopt any known communication protocol applicable to the present embodiment, preferably a controller area network (CAN, Controller Area Network) bus protocol or a local interconnect network (LIN, Local Interconnect Network) bus protocol. The message in the embodiment of the present application may be a message under the corresponding communication protocol. When the message protocol is a CAN bus protocol, the message protocol may be a data frame or a remote frame message in the CAN protocol. The message header may include CAN00 or CAN01, and the message content may include an arbitration segment, a control segment, a data segment, a CRC segment, an ACK segment and a frame end segment, wherein the data segment may be omitted. When the message protocol is a LIN bus protocol, the message header may include LIN00 or LIN01, and the message content may include a synchronization interval segment, a synchronization segment, a protected ID segment, a data segment and a checksum segment.

Claims

1. A method for testing the life of a battery pack disconnect unit (110), characterized in that: The battery pack disconnecting unit (110) belongs to the battery pack (100) and comprises: Notifying (S100) the battery pack (100) and the load simulation circuit (200), the load simulation circuit (200) performing one charge and one discharge, wherein when the load simulation circuit (200) performs the charge, current flows from the battery pack (100) to the load simulation circuit (200) and is accumulated in the load simulation circuit (200); when the load simulation circuit (200) performs the discharge, electric energy is consumed in the load simulation circuit (200); Loop (S200) to execute the notification (S100) action; The life of the battery pack disconnecting unit (110) is determined (S300) according to the number of cycles.

2. The method according to claim 1, characterized in that The notifying (S100) the battery pack (100) and the load simulation circuit (200), wherein the load simulation circuit (200) performs the charging, comprises: Sending (S110) a high-voltage signal to the battery pack (100) so that the battery pack disconnecting unit (110) performs a high-voltage action; and A charging signal is sent (S120) to the load simulation circuit (200) so that the load simulation circuit (200) absorbs electrical energy from the battery pack (100).

3. The method according to claim 1 or 2, characterized in that: The notifying (S100) the battery pack (100) and the load simulation circuit (200), wherein the load simulation circuit (200) performs the discharging, comprises: Sending (S130) a high-voltage lowering signal to the battery pack, so that the battery pack disconnection unit (110) performs a high-voltage lowering action; A discharge signal is sent (S140) to the load simulation circuit (200) so that the load simulation circuit (200) releases the absorbed electrical energy.

4. The method according to claim 3, characterized in that The notifying (S100) the battery pack (100) and the load simulation circuit (200), wherein the load simulation circuit (200) performs the discharging, comprises: After the notification (S100) executes the charging action once, after waiting for a first time period; or when the voltage of the load simulation circuit (200) reaches a voltage threshold, the battery pack (100) and the load simulation circuit (200) are notified (S100), and the load simulation circuit (200) executes the discharging.

5. The method according to any one of claims 1 to 4, characterized in that: The loop (S200) of executing the notification (S100) action includes: after the notification (S100) executes the discharge action once, waiting for a second time period, and then executing the loop (S200) action.

6. The method according to any one of claims 1 to 5, characterized in that: When the number of times the notification (S100) action is executed in the loop (S200) reaches a lifespan threshold, the loop (S200) is stopped.

7. The method according to any one of claims 1 to 6, characterized in that: When the battery pack (100) fails, the cycle (S200) is stopped.

8. The method according to claim 7, characterized in that Also includes: A fault notification from a battery pack (100) is received (S410), and a fault is determined (S420) based on the fault notification.

9. The method according to any one of claims 7-8, characterized in that: Also includes: When the battery pack (100) fails, the load simulation circuit (200) is notified (S430) to disconnect.

10. The method according to claim 9, characterized in that The high-voltage action includes: turning on the battery pack disconnection unit (110) so that the current of the battery pack (100) can flow to the load simulation circuit (200) through the battery pack disconnection unit (110) and accumulate in the load simulation circuit (200).

11. The method according to claim 9, characterized in that The lower high voltage action includes: disconnecting the battery pack disconnection unit (110) so that the current of the battery pack (100) cannot flow to the load simulation circuit (200).

12. The method according to any one of claims 1 to 11, characterized in that: The notification uses a message of a controller area network bus protocol or a local connection network bus protocol.

13. A testing device (300), characterized in that: Used for testing the life of a battery pack disconnecting unit (110), the battery pack disconnecting unit (110) belonging to the battery pack (100), the testing device comprising: a notification unit (310) for notifying (S100) the battery pack (100) and the load simulation circuit (200) that the load simulation circuit (200) performs one charge and one discharge; A central processing unit (380), used for controlling the notification unit (310) to execute the notification (S100) action in a loop (S200); A counter (320) for counting the number of cycles; The central processor (380) is further used to determine (S300) the life of the circuit breaker unit of the battery pack according to the number of cycles.

14. A testing method, characterized in that: A method for testing the life of a battery pack disconnecting unit (110), the battery pack disconnecting unit (110) belonging to the battery pack (100), the method comprising: receiving (S500) a notification that a load simulation circuit (200) performs one charge and one discharge, wherein: According to the notification of charging and discharging, the battery pack disconnection unit (110) is controlled (S510) to be turned on and off respectively, so that when the load simulation circuit (200) performs the charging, the current flows from the battery pack (100) to the load simulation circuit (200) and is accumulated in the load simulation circuit (200); when the load simulation circuit (200) performs the discharging, the electric energy is consumed in the load simulation circuit (200); According to the notification of the cyclic execution of the charging and discharging, the cycle (S520) controls the battery pack disconnecting unit (110) to be turned on and off.

15. A battery pack, characterized in that: A battery management system (130) is included for: Receive notification to perform a charge and discharge; Executing (S510) the charging and discharging once, wherein, during charging, the battery pack disconnecting unit (110) is turned on, so that the current of the battery pack (100) flows to the load simulation circuit (200) through the battery pack disconnecting unit (110) and accumulates in the load simulation circuit (200); during discharging, the battery pack disconnecting unit (110) is turned off, so that the current of the battery pack (100) cannot flow to the load simulation circuit (200); and According to the notification of cyclically performing the charging and discharging, the charging and discharging actions are cyclically performed (S520).

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