Battery loop current simulation test device and method

Abstract

The invention discloses a battery loop current simulation test device and method. The device comprises a thermal runaway simulation module, a first battery cell, at least one second battery cell and an acquisition module, the first end of the first battery cell is electrically connected with the second end of the thermal runaway simulation module, the first end of the second battery cell is electrically connected with the first end of the thermal runaway simulation module, and the second end of the second battery cell is electrically connected with the second end of the first battery cell. The second battery cell is configured to charge the first battery cell by adopting the loop current, and the acquisition module is configured to acquire the loop current, so that the loop current of the battery cell which is connected in series with the thermal runaway battery cell and is adjacent to the thermal runaway battery cell can be simulated, and whether the battery cell which is connected in series with the thermal runaway battery cell and is adjacent to the thermal runaway battery cell is overcharged or not can be determined; therefore, the battery cells can be correspondingly designed and improved in advance, thermal runaway of the subsequent battery cells caused by overcharge of the adjacent battery cells connected in series with the subsequent battery cells due to thermal runaway is avoided, and the safety and reliability of the battery energy storage system can be further improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery loop current simulation test device and method. Background Art

[0002] A battery energy storage system is a complex electrical system that uses batteries to store and release electrical energy. Its main function is to convert electrical energy into chemical energy through chemical reactions, and then convert chemical energy into electrical energy when needed, thereby achieving energy storage and regulation. A battery energy storage system is usually composed of multiple series-parallel cells (such as cylindrical cells), a battery management system, a power conversion system, etc.

[0003] In the related art, when a cell in a battery energy storage system experiences thermal runaway, the cells connected in series with the cell in thermal runaway and adjacent to it are easily affected by the cell in thermal runaway, and then thermal runaway occurs. Therefore, how to avoid thermal runaway of cells connected in series with the cell in thermal runaway and adjacent to it is a technical problem that needs to be solved urgently. Summary of the invention

[0004] In response to the deficiencies in the prior art, the present application provides a battery loop current simulation test device and method, which can not only simulate the loop current of the battery cells that are connected in series with and adjacent to the battery cells in thermal runaway, but also determine whether the battery cells that are connected in series with and adjacent to the battery cells in thermal runaway are overcharged due to the loop current, so as to avoid subsequent thermal runaway of the battery cells that are connected in series with and adjacent to the battery cells in thermal runaway.

[0005] To solve the above problems, in a first aspect, the present application provides a battery loop current simulation test device, which includes:

[0006] A thermal runaway simulation module, which is configured to simulate a battery cell in a thermal runaway state;

[0007] A first battery cell, wherein a first end of the first battery cell is electrically connected to a second end of the thermal runaway simulation module;

[0008] at least one second battery cell, wherein a first end of the second battery cell is electrically connected to a first end of the thermal runaway simulation module, and a second end of the second battery cell is electrically connected to a second end of the first battery cell; the second battery cell is configured to charge the first battery cell using a loop current;

[0009] The acquisition module is configured to acquire loop current.

[0010] Further, in the battery loop current simulation test device provided in the present application, the acquisition module includes a shunt;

[0011] Among them, the first end of the shunt is electrically connected to the first end of the thermal runaway simulation module, the second end of the shunt is electrically connected to the first end of the second battery cell, and the shunt is configured to collect loop current.

[0012] Further, in the battery loop current simulation test device provided in the present application, the battery loop current simulation test device also includes a switch device;

[0013] The first end of the switch device is electrically connected to the first end of the thermal runaway simulation module, the second end of the switch device is electrically connected to the first end of the second battery cell, and the switch device is configured to control the on and off of the circuit of the device.

[0014] Further, in the battery loop current simulation test device provided in the present application, the battery loop current simulation test device includes two second battery cells;

[0015] Among them, the first end between the two second battery cells is electrically connected to the second end, the first end of one second battery cell is electrically connected to the first end of the thermal runaway simulation module, and the second end of the other second battery cell is electrically connected to the second end of the first battery cell.

[0016] Furthermore, in the battery loop current simulation test device provided in the present application, the first battery cell and the second battery cell are battery cells of the same model.

[0017] Furthermore, in the battery loop current simulation test device provided in the present application, the battery loop current simulation test device also includes a support base;

[0018] Wherein, the first battery cell, the second battery cell and the shunt are all fixed on the supporting base.

[0019] Further, in the battery loop current simulation test device provided in the present application, the support base includes a first support portion and a second support portion;

[0020] The first support portion and the second support portion are integrally formed to form a support base with an L-shaped structure; the first battery cell and the second battery cell are both fixed on the first support portion, and the shunt is fixed on the support base.

[0021] Further, in the battery loop current simulation test device provided in the present application, the battery loop current simulation test device also includes a current acquisition interface;

[0022] The current collection interface is electrically connected to the shunt, and the current collection interface is fixed on the second supporting part.

[0023] Further, in the battery loop current simulation test device provided in the present application, the first battery cell includes a first shell, and the second battery cell includes a second shell;

[0024] The first end of the first battery cell and the first end of the second battery cell are both close to the support base, the second end of the first battery cell is electrically connected to the first shell, the second end of the second battery cell is electrically connected to the second shell, and the first shell is electrically connected to the second shell.

[0025] Further, in the battery loop current simulation test device provided in the present application, the battery loop current simulation test device also includes an electrical connector;

[0026] One end of the electrical connector is electrically connected to the first shell, and the other end of the electrical connector is electrically connected to the second shell.

[0027] In a second aspect, the present application further provides a battery loop current simulation test method, which is applied to the battery loop current simulation test device provided in the first aspect, and the battery loop current simulation test method includes:

[0028] Obtain the target resistance value of the battery cell in the thermal runaway state;

[0029] Adjust the resistance value of the thermal runaway simulation module to the target resistance value;

[0030] Controlling the second battery cell to charge the first battery cell and collecting loop current;

[0031] Determine whether the first battery cell is in an overcharge state according to the loop current.

[0032] The battery loop current simulation test device provided in the present application includes a thermal runaway simulation module, a first battery cell, at least one second battery cell and an acquisition module, wherein the first end of the first battery cell is electrically connected to the second end of the thermal runaway simulation module, the first end of the second battery cell is electrically connected to the first end of the thermal runaway simulation module, and the second end of the second battery cell is electrically connected to the second end of the first battery cell, and the second battery cell is configured to charge the first battery cell with a loop current, and the acquisition module is configured to acquire the loop current, which can not only simulate the loop current of the battery cell connected in series and adjacent to the battery cell with thermal runaway, but also determine whether the battery cell connected in series and adjacent to the battery cell with thermal runaway is overcharged due to the loop current, and also can be designed and improved accordingly in advance based on this, so as to avoid the subsequent battery cell from thermal runaway, which may cause the battery cell connected in series and adjacent to it to have thermal runaway due to overcharging, thereby improving the safety and reliability of the battery energy storage system. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0034] Figure 1 A circuit schematic diagram of a battery loop current simulation test device provided in an embodiment of the present application;

[0035] Figure 2A schematic diagram of the structure of a battery loop current simulation test device provided in an embodiment of the present application;

[0036] Figure 3 A schematic diagram of the structure of the support base provided in the embodiment of the present application;

[0037] Figure 4 A flowchart of a battery loop current simulation test method provided in an embodiment of the present application.

[0038] Among them, 10 is a thermal runaway simulation module, 20 is a first battery cell, 201 is a first shell, 30 is a second battery cell, 301 is a second shell, 40 is a collection module, 401 is a shunt, 50 is a switch device, 60 is a support base, 601 is a first support part, 6011 is a first groove, 602 is a second support part, 6021 is a second groove, 603 is a third support part, 70 is a current collection interface, and 80 is an electrical connector. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0040] It should be understood that when used in this specification and the appended claims, the terms "include" and "comprises" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0041] It should also be understood that the terms used in this application specification are only for the purpose of describing specific embodiments and are not intended to limit the application. As used in this application specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0042] It should be further understood that the term “and / or” used in the specification and appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0043] In addition, in this application, unless otherwise clearly specified or limited in the embodiments, the terms "installed", "connected", "connected" and "fixed" etc. appearing in the embodiments should be understood in a broad sense. For example, the connection can be a fixed connection, a detachable connection, or an integrated connection. It can be understood that it can also be a mechanical connection, an electrical connection, etc.; of course, it can also be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal connection of two elements, or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific implementation situation.

[0044] In the related art, the battery energy storage system includes multiple battery modules, and each battery module can be designed in a 2S2P manner. Among them, "S" stands for series (Series), and "P" stands for parallel (Parallel). When a battery cell in the battery energy storage system has thermal runaway, that is, when a battery cell in the 2S2P module has thermal runaway, the battery cells connected in series with and adjacent to the battery cell with thermal runaway are affected by the loop current, and the battery cells in the 2S2P module that are connected in parallel with the battery cell with thermal runaway will charge the battery cells connected in series with and adjacent to the battery cell with thermal runaway. At this time, the battery cells connected in series with and adjacent to the battery cell with thermal runaway are prone to overcharging, which in turn causes the battery cells connected in series with and adjacent to the battery cell with thermal runaway to also experience thermal runaway.

[0045] To this end, the present application provides a battery loop current simulation test device and method, which can simulate the loop current of the battery cells that are connected in series with and adjacent to the battery cells in thermal runaway, and then determine whether the battery cells that are connected in series with and adjacent to the battery cells in thermal runaway are overcharged due to the loop current, so as to avoid subsequent thermal runaway of the battery cells that are connected in series with and adjacent to the battery cells in thermal runaway.

[0046] See also Figure 1 and Figure 2 , Figure 1 A circuit schematic diagram of a battery loop current simulation test device provided in an embodiment of the present application; Figure 2 A schematic diagram of the structure of a battery loop current simulation test device provided in an embodiment of the present application.

[0047] like Figure 1 and Figure 2 As shown, the present application provides a battery loop current simulation test device, which includes:

[0048] A thermal runaway simulation module 10, wherein the thermal runaway simulation module 10 is configured to simulate a battery cell in a thermal runaway state;

[0049] A first battery cell 20, wherein a first end of the first battery cell 20 is electrically connected to a second end of the thermal runaway simulation module 10;

[0050] At least one second battery cell 30, a first end of the second battery cell 30 is electrically connected to the first end of the thermal runaway simulation module 10, and a second end of the second battery cell 30 is electrically connected to the second end of the first battery cell 20; the second battery cell 30 is configured to charge the first battery cell 20 using a loop current;

[0051] The acquisition module 40 is configured to acquire loop current.

[0052] Thermal runaway of a battery cell refers to a phenomenon in which the temperature inside the battery cell rises sharply due to some reason, which in turn causes the internal materials of the battery cell to decompose, melt, or even burn. After a battery cell experiences thermal runaway, the battery cell can be understood as a resistor. Therefore, the present application sets up a thermal runaway simulation module in the battery loop current simulation test device to simulate the battery cell in a thermal runaway state.

[0053] In this embodiment, after the thermal runaway simulation module 10, the first battery cell 20, and the second battery cell 30 are electrically connected to form a loop, the acquisition module 40 can collect current from the loop, and the current collected by the acquisition module 40 is the loop current mentioned in this application. After the acquisition module 40 collects the loop current, the application can determine whether the second battery cell overcharges the first battery cell based on the loop current.

[0054] The thermal runaway simulation module 10 can be a battery short-circuit device, and the battery short-circuit device can adjust the resistance value to simulate the resistance value generated after the battery cell thermal runaway. Therefore, the thermal runaway simulation module 10 can be understood as a resistor R. At the same time, the first battery cell 20 can be understood as a battery cell connected in series and adjacent to the thermal runaway simulation module 10, and the second battery cell 30 can be understood as a battery cell connected in parallel with the first battery cell 20 connected in series and the thermal runaway simulation module 10.

[0055] Specifically, the first end of the first battery cell 20 and the first end of the second battery cell 30 can be both positive and negative electrodes at the same time, and then when the thermal runaway simulation module 10 is configured to simulate a battery cell in a thermal runaway state, the second battery cell 30 can be configured to charge the first battery cell 20, and the charging current of the second battery cell 30 for charging the first battery cell 20 can be understood as the loop current in the battery loop current simulation test device. At this time, the acquisition module can be used to collect the loop current, and the loop current collected by the acquisition module can be used to confirm whether the first battery cell 20 is in an overcharged state. If it is confirmed that the first battery cell 20 is in an overcharged state, the first battery cell 20 can be designed and improved accordingly in advance before the first battery cell 20 is produced, thereby avoiding thermal runaway of subsequent batteries due to thermal runaway, which causes thermal runaway of batteries connected in series and adjacent to it due to overcharging, thereby improving the safety and reliability of the battery energy storage system.

[0056] It should be noted that when the first end of the first battery cell 20 and the first end of the second battery cell 30 can be positive electrodes at the same time, the second end of the first battery cell 20 and the second end of the second battery cell 30 are negative electrodes at the same time; when the first end of the first battery cell 20 and the first end of the second battery cell 30 can be negative electrodes at the same time, the second end of the first battery cell 20 and the second end of the second battery cell 30 are positive electrodes at the same time.

[0057] The battery loop current simulation test device provided in the present application includes a thermal runaway simulation module 10, a first battery cell 20, at least one second battery cell 30 and a collection module 40, wherein the first end of the first battery cell 20 is electrically connected to the second end of the thermal runaway simulation module 10, the first end of the second battery cell 30 is electrically connected to the first end of the thermal runaway simulation module 10, and the second end of the second battery cell 30 is electrically connected to the second end of the first battery cell 20, and the second battery cell 30 is configured to charge the first battery cell 20 with a loop current, and the collection module is configured to collect the loop current, which can not only simulate the loop current of the battery cell connected in series and adjacent to the thermal runaway battery cell, but also determine whether the battery cell connected in series and adjacent to the thermal runaway battery cell is overcharged due to the loop current, and also can be designed and improved accordingly in advance based on this, so as to avoid the subsequent battery cell from thermal runaway, which causes the battery cell connected in series and adjacent to it to have thermal runaway due to overcharging, thereby improving the safety and reliability of the battery energy storage system.

[0058] In some embodiments, Figure 1 and Figure 2 As shown, the battery loop current simulation test device also includes a shunt 401; wherein, the first end of the shunt 401 is electrically connected to the first end of the thermal runaway simulation module 10, the second end of the shunt 401 is electrically connected to the first end of the second battery cell 30, and the shunt 401 is configured to collect loop current.

[0059] In this embodiment, the shunt 401 is arranged between the first end of the thermal runaway simulation module 10 and the first end of the second battery cell 30. The shunt 401 can collect the charging current of the second battery cell 30 to the first battery cell 20, that is, the loop current in the battery loop current simulation test device, and then obtain the loop current in the battery loop current simulation test device, so as to confirm whether the first battery cell 20 is in an overcharged state.

[0060] The shunt 401 is an electronic device mainly used to measure current. Its working principle is based on Ohm's law (I=U / R), and by introducing a low-resistance resistor (i.e., the shunt 401) into the circuit, a portion of the current passes through the resistor to generate a voltage drop, thereby indirectly measuring the current.

[0061] Specifically, after the shunt 401 is arranged between the first end of the thermal runaway simulation module 10 and the first end of the second battery cell 30, if the second battery cell 30 charges the first battery cell 20, there will be a voltage drop at both ends of the shunt 401. By collecting the size of the voltage drop, the size of the loop current can be calculated, so as to confirm whether the first battery cell 20 is in an overcharged state.

[0062] It should be noted that the shunt 401 may also be disposed between the second end of the thermal runaway simulation module 10 and the first end of the first battery cell 20, or between the second end of the first battery cell 20 and the second end of the second battery cell 30. If two second battery cells 30 are provided in the battery loop current simulation test device, the shunt 401 may also be disposed between the two second battery cells 30.

[0063] In some embodiments, Figure 1 and Figure 2 As shown, the battery loop current simulation test device also includes a switching device 50; wherein, the first end of the switching device 50 is electrically connected to the first end of the thermal runaway simulation module 10, and the second end of the switching device 50 is electrically connected to the first end of the second battery cell 30, and the switching device 50 is configured to control the on and off of the circuit of the device.

[0064] In this embodiment, the switch device 50 can be arranged between the first end of the thermal runaway simulation module 10 and the first end of the second battery cell 30. The switch device 50 is mainly used to control the closing and opening of the circuit of the device, and can be a relay. When it is necessary to use a battery circuit current simulation test device to perform a charging test on the first battery cell 20, the thermal runaway simulation module 10 can be configured to simulate a battery cell in a thermal runaway state, and the relay can be closed, at which time the second battery cell 30 can charge the first battery cell 20; when it is not necessary to use a battery circuit current simulation test device to perform a charging test on the first battery cell 20, the relay can be opened.

[0065] It should be noted that the switch device 50 may also be disposed between the second end of the thermal runaway simulation module 10 and the first end of the first battery cell 20, or between the second end of the first battery cell 20 and the second end of the second battery cell 30. If two second battery cells 30 are provided in the battery loop current simulation test device, the switch device 50 may also be disposed between the two second battery cells 30.

[0066] In some embodiments, Figure 1 and Figure 2 As shown, the battery loop current simulation test device includes two second battery cells 30; wherein the first end and the second end between the two second battery cells 30 are electrically connected, the first end of one second battery cell 30 is electrically connected to the first end of the thermal runaway simulation module 10, and the second end of the other second battery cell 30 is electrically connected to the second end of the first battery cell 20.

[0067] In this embodiment, the battery loop current simulation test device can be understood as a 2S2P module. The 2S2P module is a battery configuration method, where "S" stands for series connection (Series) and "P" stands for parallel connection (Parallel).

[0068] Specifically, the battery loop current simulation test device provided in the present application can be understood as a group of batteries formed by two battery cells connected in series, and then two groups of batteries connected in parallel, so that the battery module in the battery energy storage system can be more closely tested.

[0069] Furthermore, when there are two second cells 30 in the battery loop current simulation test device, the first cell 20 and the second cell 30 are cells of the same model, and the thermal runaway simulation module 10 can be configured to simulate the first cell 20 in a thermal runaway state. The first cell 20, as a cell connected in series and adjacent to the thermal runaway simulation module 10, will be charged by the second cell 30. If the first cell 20 is fully charged, the first cell 20 will be in an overcharged state, which will damage the first cell 20, thereby causing thermal runaway in the first cell 20. Therefore, the battery loop current simulation test device can be designed with 2S2P, which can be closer to the battery module in the battery energy storage system.

[0070] It should be noted that the battery loop current simulation test device provided in the present application can also be designed in the manner of 3S2P, 3S3P, etc., which can be selected according to the actual application, and the present application does not make any specific limitation.

[0071] In some embodiments, Figure 2 As shown, the battery loop current simulation test device further includes a support base 60 ; wherein the first battery cell 20 , the second battery cell 30 , and the shunt 401 are all fixed on the support base 60 .

[0072] In this embodiment, the support base 60 is mainly used to support and fix the first battery cell 20, the second battery cell 30, the shunt 401 and the relay and other devices, and can fix and integrate the first battery cell 20, the second battery cell 30, the shunt 401 and the relay and other devices into one.

[0073] In some embodiments, Figure 2 As shown, the support base 60 includes a first support portion 601 and a second support portion 602; wherein the first support portion 601 and the second support portion 602 are integrally formed to form an L-shaped support base 60; the first battery cell 20 and the second battery cell 30 are both fixed on the first support portion 601, and the diverter 401 is fixed on the second support portion 602.

[0074] Specifically, since the volume of the diverter 401 is smaller than the volume of the first battery cell 20 and the second battery cell 30, the support base 60 is designed as an L-shaped structure, that is, the height of the first support part 601 is lower than the height of the second support part 602, so as to facilitate better electrical connection between the diverter 401 and the battery cells.

[0075] Furthermore, in some embodiments, Figure 3 As shown, the support base 60 further includes a third support portion 603, which is mainly used to support the relay. Similarly, the height of the third support portion 603 can be designed according to the volume of the relay.

[0076] In addition, in order to better fix the first battery cell 20 and the second battery cell 30, the present application can also set a first groove 6011 on the first support part 601. The number of the first grooves 6011 can be set according to the number of battery cells on the first support part 601. The battery cells can be directly embedded in the first grooves 6011 for fixation, and the first grooves 6011 can also pass through the support base 60.

[0077] In some embodiments, Figure 2 As shown, the battery loop current simulation test device also includes a current collection interface 70 ; wherein the current collection interface 70 is electrically connected to the shunt 401 , and the current collection interface 70 is fixed on the support base 60 , specifically, can be fixed on the second support portion 602 .

[0078] In this embodiment, the current acquisition interface 70 can be electrically connected to the shunt 401, and the current acquisition interface 70 can be connected to other devices to facilitate the calculation of the voltage drop across the shunt 401, so as to determine the loop current in the battery loop current simulation test device, and then determine whether the first battery cell 20 is in an overcharge state.

[0079] Furthermore, since the volume of the diverter 401 is relatively small, in order to facilitate the fixing of the diverter 401, as shown in FIG. Figure 3 As shown, a second groove 6021 may be provided on the second supporting portion 602 , and the diverter 401 may be fixed in the second groove 6021 .

[0080] In some embodiments, Figure 2 As shown, the battery loop current simulation test device further includes an electrical connector 80 ; wherein one end of the electrical connector 80 is electrically connected to the second end of the first battery cell 20 , and the second end of the electrical connector 80 is electrically connected to the second end of the second battery cell 30 .

[0081] Furthermore, the first battery cell 20 includes a first shell 201, and the second battery cell 30 includes a second shell 301; wherein the first end of the first battery cell 20 and the first end of the second battery cell 30 are both close to the support base 60, the second end of the first battery cell 20 is electrically connected to the first shell 201, the second end of the second battery cell 30 is electrically connected to the second shell 301, and the electrical connector 80 is electrically connected to the first shell and the second shell, respectively.

[0082] Specifically, the first end of the first battery cell 20 and the first end of the second battery cell 30 are both close to the support base 60, the second end of the first battery cell 20 is electrically connected to the first shell 201, the second end of the second battery cell 30 is electrically connected to the second shell 301, and the electrical connector 80 is electrically connected to the first shell 201 and the second shell 301 respectively.

[0083] In the present embodiment, the first battery cell 20 and the second battery cell 30 may be cylindrical battery cells. Since the first battery cell 20 and the second battery cell 30 are both embedded in the first groove 6011, the negative electrodes of the first battery cell 20 and the second battery cell 30 are both in the first groove 6011. When the electrical connector 80 is used to electrically connect the negative electrode of the first battery cell 20 with the negative electrode of the second battery cell 30, in order to facilitate the electrical connection between the negative electrode of the first battery cell 20 and the negative electrode of the second battery cell 30, the first shell 201 of the first battery cell 20 and the second shell 301 of the second battery cell 30 can be made to have a conductive function. At the same time, the negative electrode of the first battery cell 20 is electrically connected to the first shell 201, and the negative electrode of the second battery cell 30 is electrically connected to the second shell 301. The electrical connector 80 is used to electrically connect the first shell 201 and the second shell 301, so that the negative electrode of the first battery cell 20 and the negative electrode of the second battery cell 30 can be electrically connected.

[0084] In some embodiments, Figure 4 As shown, the present application also provides a battery loop current simulation test method, which is applied to the battery loop current simulation test device provided in the above embodiment. The battery loop current simulation test method includes: step S110, step S120, step S130 and step S140.

[0085] S110, obtaining a target resistance value of the battery cell in a thermal runaway state;

[0086] S120, adjusting the resistance value of the thermal runaway simulation module 10 to a target resistance value;

[0087] S130, controlling the second battery cell 30 to charge the first battery cell 20, and collecting loop current;

[0088] S140 , determining whether the first battery cell 20 is in an overcharge state according to the loop current.

[0089] In this embodiment, the target resistance value is the resistance value of the first battery cell 20 in the thermal runaway state, which can be understood as the reference value of the external short-circuit resistance of the battery cell in the national standard, and the reference value can be 5 mΩ.

[0090] Specifically, after obtaining the target resistance value of the battery cell in the thermal runaway state, the resistance value of the thermal runaway simulation module 10 can be adjusted to the target resistance value. At the same time, two second battery cells 30 can be set in the battery loop current simulation test device. At this time, the loop of the battery loop current simulation test device can be turned on. Specifically, a relay can be used to turn on the loop of the battery loop current simulation test device.

[0091] After the loop of the battery loop current simulation test device is turned on, the second battery cell 30 can charge the first battery cell 20. At this time, the loop current of the battery loop current simulation test device can be collected. Specifically, the shunt 401 can be used to collect the loop current. After collecting the loop current, it is possible to determine whether the current first battery cell 20 is in an overcharged state based on the state of the first battery cell 20 before being charged by the second battery cell 30 and the loop current, so that the battery module can be improved in advance, thereby avoiding thermal runaway of subsequent battery cells due to thermal runaway, which may cause thermal runaway of the battery cells connected in series and adjacent to it due to overcharging.

[0092] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in the present application, and these modifications or replacements should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A battery loop current simulation test device, characterized in that: include: A thermal runaway simulation module, wherein the thermal runaway simulation module is configured to simulate a battery cell in a thermal runaway state; A first battery cell, wherein a first end of the first battery cell is electrically connected to a second end of the thermal runaway simulation module; at least one second battery cell, wherein a first end of the second battery cell is electrically connected to a first end of the thermal runaway simulation module, and a second end of the second battery cell is electrically connected to a second end of the first battery cell; the second battery cell is configured to charge the first battery cell using a loop current; A collection module is configured to collect the loop current.

2. The battery loop current simulation test device according to claim 1, characterized in that: The acquisition module includes a diverter; Among them, the first end of the shunt is electrically connected to the first end of the thermal runaway simulation module, the second end of the shunt is electrically connected to the first end of the second battery cell, and the shunt is configured to collect the loop current.

3. The battery loop current simulation test device according to claim 1, characterized in that: The device also includes a switching device; The first end of the switch device is electrically connected to the first end of the thermal runaway simulation module, the second end of the switch device is electrically connected to the first end of the second battery cell, and the switch device is configured to control the on and off of the circuit of the device.

4. The battery loop current simulation test device according to claim 1, characterized in that: The device includes two second cells; Among them, the first end and the second end between two of the second battery cells are electrically connected, the first end of one of the second battery cells is electrically connected to the first end of the thermal runaway simulation module, and the second end of the other second battery cell is electrically connected to the second end of the first battery cell.

5. The battery loop current simulation test device according to any one of claims 2 to 4, characterized in that: The device also includes a support base; Wherein, the first battery cell, the second battery cell and the diverter are all fixed on the supporting base.

6. The battery loop current simulation test device according to claim 5, characterized in that: The support base includes a first support portion and a second support portion; The first support portion and the second support portion are integrally formed to form a support base with an L-shaped structure; the first battery cell and the second battery cell are both fixed on the first support portion, and the shunt is fixed on the second support portion.

7. The battery loop current simulation test device according to claim 5, characterized in that: The device also includes a current collection interface; Wherein, the current collection interface is electrically connected to the shunt, and the current collection interface is fixed on the supporting base.

8. The battery loop current simulation test device according to claim 5, characterized in that: The first battery cell includes a first shell, and the second battery cell includes a second shell; The first end of the first battery cell and the first end of the second battery cell are both close to the support base, the second end of the first battery cell is electrically connected to the first shell, the second end of the second battery cell is electrically connected to the second shell, and the first shell is electrically connected to the second shell.

9. The battery loop current simulation test device according to claim 8, characterized in that: The device also includes an electrical connector; One end of the electrical connector is electrically connected to the first shell, and the other end of the electrical connector is electrically connected to the second shell.

10. A battery loop current simulation test method, characterized in that: The battery loop current simulation test device applied to any one of claims 1 to 9, the method comprising: Obtain the target resistance value of the battery cell in the thermal runaway state; Adjusting the resistance value of the thermal runaway simulation module to the target resistance value; Controlling the second battery cell to charge the first battery cell, and collecting the loop current; Determine whether the first battery cell is in an overcharge state according to the loop current.

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