Battery pack heating method and device, electronic equipment and storage medium

Abstract

The invention provides a battery pack heating method and device, electronic equipment and a storage medium. The method comprises the following steps: acquiring operation information corresponding to a battery pack; judging whether the operation information meets a heating starting condition or not; if the operation information meets the heating starting condition, a heating control switch is closed, and heating of the heating film to the battery pack is started; if the operation information does not meet the heating starting condition, whether the operation information meets a heating ending condition or not is judged; if the operation information meets the heating ending condition, the heating control switch is switched off, and heating of the battery pack by the heating film is stopped. The low-temperature battery pack is heated through the heating film, and the charging safety of the battery pack under the low-temperature condition is guaranteed.

Description

Technical Field

[0001] The present application relates to the technical field of low-temperature battery charging, and in particular to a battery pack heating method, device, electronic device and storage medium. Background Art

[0002] Although lithium-ion batteries have strong technical advantages in terms of energy density, power density, and cycle life, they have poor anti-abuse capabilities, and their charge and discharge characteristics and cycle life are greatly affected by the use environment and conditions. Almost all transmission processes in lithium-ion batteries are related to temperature, so the operating temperature of lithium-ion batteries has an important impact on the overall performance of the battery.

[0003] When the battery temperature is lower than this working range, the negative electrode's ability to embed lithium is also poor due to the poor activity of the internal materials of the battery and the slow electrochemical reaction rate. In addition, the internal resistance of the battery increases, the polarization effect is enhanced, and the charging capacity and safety are greatly reduced. Charging in such a low temperature environment will not only cause lithium precipitation on the surface of the negative electrode, affecting the safety of the battery, but may also increase the terminal voltage of the battery, causing the internal lithium dendrites to pierce the diaphragm, causing an internal short circuit and leading to thermal runaway. Therefore, in order to maintain good performance of the battery, the ambient temperature during use should be controlled within a certain range. The battery needs to be preheated and kept warm at low temperatures. Summary of the invention

[0004] In view of this, the purpose of the present application is to provide at least a battery pack heating method, device, electronic device and storage medium, which can heat the low-temperature battery pack through a heating film to ensure the safety of charging the battery pack under low temperature conditions.

[0005] This application mainly includes the following aspects:

[0006] In the first aspect, the embodiments of the present application provide

[0007] A battery pack heating method is applied to a battery system. The battery system includes a battery pack, a heating film and a heating control switch. The heating film covers the battery pack. A plurality of temperature detection sensors are arranged inside the battery pack. The heating film is connected to the heating control switch. The method includes: collecting operation information corresponding to the battery pack; judging whether the operation information meets the heating start condition; if the operation information meets the heating start condition, closing the heating control switch and starting the heating film to heat the battery pack; if the operation information does not meet the heating start condition, judging whether the operation information meets the heating end condition; if the operation information meets the heating end condition, disconnecting the heating control switch and turning off the heating film to heat the battery pack.

[0008] In a possible embodiment, the operating information also includes the heating film enable state, the heating film heating state and the minimum temperature of the battery pack, wherein, after collecting the operating information corresponding to the battery pack, the method also includes: determining whether the heating film enable state is enabled; if the heating film enable state is enabled, obtaining the heating film heating state; if the heating film heating state is heating start, determining whether the operating information meets the heating end condition, if the operating information meets the heating end condition, disconnecting the heating control switch, and turning off the heating of the battery pack by the heating film; if the heating film heating state is heating disconnected, determining whether the minimum temperature of the battery pack is less than or equal to the heating start temperature of the battery pack; if the minimum temperature of the battery pack is less than or equal to the heating start temperature of the battery pack, determining whether the operating information meets the heating start condition; if the heating film enable state is not enabled, providing a heating film enable fault prompt, and performing no subsequent processing.

[0009] In a possible embodiment, the operating information also includes the remaining power corresponding to each battery cell and the battery pack charging current, wherein the heating start condition includes one of the following: the minimum temperature of the battery pack is within a preset low temperature range and the minimum remaining power is greater than the first preset power; the minimum temperature of the battery pack is greater than the upper limit of the preset low temperature range, and the minimum remaining power is greater than or equal to the second preset power, and the second preset power is less than the first preset power; the minimum temperature of the battery pack is greater than the upper limit of the preset low temperature range, the minimum remaining power is less than the second preset power, and the battery pack charging current is greater than the first preset current value.

[0010] In a possible embodiment, the operating information also includes voltage information and fault detection results, wherein the heating end conditions include: the heating film enable state is not enabled; the voltage information corresponding to the battery system meets the preset undervoltage condition; the battery system is in the shutdown process, in a dormant state or in a self-test process before power-on; the fault detection result indicates that the battery system has a fault; the external ambient temperature of the battery system is less than or equal to the lower limit of the preset low temperature range; the minimum temperature of the battery pack is greater than or equal to the first heating end temperature; the maximum temperature of the battery pack is greater than or equal to the second heating end temperature, and the second heating end temperature is greater than the first heating end temperature.

[0011] In a possible embodiment, the battery system also includes at least one voltage acquisition module, which is used to collect the cell voltage corresponding to each battery cell. The voltage information includes the cell voltage corresponding to each battery cell, the module voltage corresponding to the voltage acquisition module and the power supply voltage corresponding to the battery system. The module voltage is the sum of multiple cell voltages collected by the voltage acquisition module, and the power supply voltage is the sum of the cell voltages corresponding to all battery cells in the battery pack. The preset undervoltage conditions include: any cell voltage is less than or equal to a preset cell undervoltage value; the module voltage is less than or equal to a preset module undervoltage value; the power supply voltage is less than or equal to a preset power supply undervoltage value; any cell voltage is less than or equal to a preset cell shutdown voltage; the module voltage is less than or equal to a preset module shutdown voltage; the power supply voltage is less than or equal to a preset power shutdown voltage.

[0012] In a possible implementation, the method further includes: performing fault detection on the heating film in real time and generating a fault detection result.

[0013] In a possible embodiment, the battery system also includes a Hall sensor for collecting the average current of the heating film. The heating film failure includes the heating film being offline, the heating film being open-circuited, and the heating control switch being stuck. The heating film failure is detected in the following manner: multiple sampling reference voltages corresponding to the Hall sensor are continuously collected. If there are a continuous preset number of sampling reference voltages that are not within the standard reference voltage range, it is determined that the heating film is offline; when the heating state of the heating film is heating-on, if the heating film average current is less than the second preset current value, it is determined that the heating film is open-circuited; when the heating state of the heating film is heating-off, if the heating film average current is greater than or equal to the third preset current value, it is determined that the heating control switch is stuck; if the heating film average current is greater than the fourth preset current value, it is determined that the heating film is short-circuited; if the heating film average current is less than the fifth preset current value, it is determined that the heating film is reversely connected.

[0014] In the second aspect, the present application also provides a battery heating device, which is applied to a battery system. The battery system includes a battery pack, a heating film and a heating control switch. The heating film covers the battery pack. A plurality of temperature detection sensors are arranged inside the battery pack. The heating film is connected to the heating control switch. The device includes: an acquisition module, which is used to acquire operating information corresponding to the battery pack; a first judgment module, which is used to judge whether the operating information meets the heating start condition; a heating start module, which is used to close the heating control switch and start the heating of the battery pack by the heating film if the operating information meets the heating start condition; a second judgment module, which is used to judge whether the operating information meets the heating end condition if the operating information does not meet the heating start condition; a heating shutdown module, which is used to disconnect the heating control switch and turn off the heating of the battery pack by the heating film if the operating information meets the heating end condition.

[0015] In a third aspect, an embodiment of the present application further provides an electronic device, comprising: a processor, a memory and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor and the memory communicate through the bus, and the machine-readable instructions are executed by the processor to execute the steps of the battery pack heating method in the first aspect or any possible implementation manner of the first aspect.

[0016] In a fourth aspect, an embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the battery pack heating method in the above-mentioned first aspect or any possible implementation manner of the first aspect are executed.

[0017] The embodiments of the present application provide a method and device for heating a battery pack, an electronic device and a storage medium, which are applied to a battery system. The battery system includes a battery pack, a heating film and a heating control switch. The heating film covers the battery pack. At least one temperature detection sensor is provided inside the battery pack. The heating film is connected to the heating control switch. The method includes: collecting the operation information corresponding to the battery pack; judging whether the operation information meets the heating start condition; if the operation information meets the heating start condition, closing the heating control switch and starting the heating of the battery pack by the heating film; if the operation information does not meet the heating start condition, judging whether the operation information meets the heating end condition; if the operation information meets the heating end condition, disconnecting the heating control switch and turning off the heating of the battery pack by the heating film. The present application realizes heating of a low-temperature battery pack by a heating film, thereby ensuring the safety of charging the battery pack under low-temperature conditions.

[0018] The benefits of this application are:

[0019] In a low-temperature environment, the heating film is turned on to heat the battery cell, effectively raising the temperature of the battery pack. After the battery cell temperature is raised, large current charging and discharging are performed while ensuring the safety of the battery cell at low temperatures. This greatly relaxes the use scenarios of lithium-ion batteries and avoids thermal runaway caused by the increase of battery terminal voltage and the internal lithium dendrites piercing the diaphragm.

[0020] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 A flow chart of a battery pack heating method provided in an embodiment of the present application is shown;

[0023] Figure 2 One of the flow charts of another battery pack heating method provided in an embodiment of the present application is shown;

[0024] Figure 3 A second flowchart of another battery pack heating method provided in an embodiment of the present application is shown;

[0025] Figure 4 A third flowchart of another battery pack heating method provided in an embodiment of the present application is shown;

[0026] Figure 5 A fourth flowchart of another battery pack heating method provided in an embodiment of the present application is shown;

[0027] Figure 6 A fifth flowchart of another battery pack heating method provided in an embodiment of the present application is shown;

[0028] Figure 7 A schematic structural diagram of a battery pack heating device provided in an embodiment of the present application is shown;

[0029] Figure 8 A schematic structural diagram of an electronic device provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0030] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It should be understood that the drawings in the present application only serve the purpose of explanation and description and are not used to limit the scope of protection of the present application. In addition, it should be understood that the schematic drawings are not drawn in real proportion. The flowchart used in this application shows the operations implemented according to some embodiments of the present application. It should be understood that the operations of the flowchart can be implemented out of sequence, and the steps without logical context can be reversed in order or implemented simultaneously. In addition, those skilled in the art, under the guidance of the content of the present application, can add one or more other operations to the flowchart, or remove one or more operations from the flowchart.

[0031] In addition, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0032] Although lithium-ion batteries have strong technical advantages in terms of energy density, power density, cycle life, etc., they have poor anti-abuse capabilities, and their charge and discharge characteristics and cycle life are greatly affected by the use environment and conditions. Almost all transmission processes in lithium-ion batteries are related to temperature. Therefore, the operating temperature of lithium-ion batteries has an important impact on the overall performance of the battery.

[0033] When the battery temperature drops to a certain level, the activity of the internal materials of the battery is poor and the electrochemical reaction rate slows down, so the ability of the negative electrode to embed lithium is also poor. In addition, the battery temperature is too low, which causes the internal resistance of the battery to increase and the polarization effect to increase, and the corresponding charging capacity and safety are greatly reduced.

[0034] It can be seen from this that charging in a low-temperature environment will not only cause lithium deposition on the surface of the battery's negative electrode, affecting the safety of the battery, but may also increase the battery's terminal voltage, causing internal lithium dendrites to pierce the diaphragm, causing an internal short circuit and leading to thermal runaway.

[0035] It can be seen from this that if the battery is charged in a low temperature environment, there will be great safety risks.

[0036] Based on this, the embodiments of the present application provide a battery pack heating method, device, electronic device and storage medium, which heat the low-temperature battery pack through a heating film to ensure the safety of charging the battery pack under low temperature conditions, as follows:

[0037] See also Figure 1 , Figure 1 A flow chart of a battery pack heating method provided in an embodiment of the present application is shown. Figure 1 As shown, the battery pack heating method provided in the embodiment of the present application is applied to a battery system, the battery system includes a battery pack, a heating film and a heating control switch, the heating film covers the battery pack, a plurality of temperature detection sensors are arranged inside the battery pack, the heating film is connected to the heating control switch, the temperature detection sensor can be an NTC resistor, at least one temperature detection sensor is distributed at different positions inside the battery pack, and the heating control switch can be a relay.

[0038] The following steps are involved:

[0039] S100: Collect operating information corresponding to the battery pack.

[0040] S200: Determine whether the operation information satisfies the heating start condition.

[0041] S300: If the operation information satisfies the heating start condition, the heating control switch is closed to start the heating film to heat the battery pack.

[0042] S400: If the operation information does not meet the heating start condition, determine whether the operation information meets the heating end condition.

[0043] S500: If the operation information satisfies the heating end condition, the heating control switch is turned off to turn off the heating film for heating the battery pack.

[0044] If the operation information does not meet the heating end condition, the process returns to step S100.

[0045] In steps S100 to S400, during the operation of the battery system, the operating information corresponding to the battery system is monitored. When the operating information triggers the heating start condition corresponding to the heating film, the heating control switch is triggered to close, so that the heating film heats the battery pack. When the operating information triggers the heating end condition corresponding to the heating film, the heating control switch is triggered to open, so as to stop the heating film from heating the battery pack.

[0046] In a specific implementation, the operating information includes the heating film enable status, the heating film heating status, the minimum temperature of the battery pack, the remaining power corresponding to each battery cell, the battery pack charging current and the fault detection result. The minimum temperature of the battery pack is the lowest temperature collected by multiple temperature detection sensors. The battery pack includes multiple battery cells, and each battery cell is also provided with a SOC sensor for collecting the remaining power corresponding to the battery cell.

[0047] In a preferred embodiment, after step S100, the method of the present application further includes:

[0048] Determine whether the enabling state of the heating film is enabled. If the enabling state of the heating film is enabled, obtain the heating state of the heating film. If the heating state of the heating film is heating start, determine whether the operation information meets the heating end condition. If the operation information meets the heating end condition, disconnect the heating control switch to turn off the heating of the battery pack by the heating film. If the heating state of the heating film is heating disconnected, determine whether the minimum temperature of the battery pack is less than or equal to the heating start temperature of the battery pack. If the minimum temperature of the battery pack is less than or equal to the heating start temperature of the battery pack, determine whether the operation information meets the heating start condition. If the enabling state of the heating film is not enabled, a heating film enabling fault prompt is given and no subsequent processing is performed.

[0049] During the process, under normal circumstances, after the heating film is put into use or the battery system is initialized, it will obtain the heating film enable instruction sent by the host computer. If the heating film enable instruction is an instruction to turn on the heating function, the heating film will change its corresponding heating film enable state from the default state to enabled. If the heating film enable instruction is an instruction to turn off the heating function, the heating film will change its corresponding heating film enable state from the default state to disabled. Because the premise of starting the heating film control state processing flow is that the heating film is in an enabled state, therefore, before formally entering the processing of the heating film control state, the heating film enable state detection is first performed. Its main purpose is to confirm whether the heating film is successfully enabled. The heating module enable state can be obtained by obtaining the corresponding heating module enable flag. If the heating film enable state is enabled, it means that the heating film is successfully enabled, and the processing flow of the heating film control state is formally carried out. If the heating film enable state is disabled, it means that the heating film fails to be enabled. At this time, a heating film enable fault prompt is required, and the subsequent processing flow of the heating film control state is not entered.

[0050] After entering the processing flow of the heating film control state, the heating state of the heating film must be detected first. This is because when the heating state of the heating film is heating start, it means that the heating film is already in heating operation. At this time, it means that there is no need to perform the heating start condition judgment process again, and to avoid repeatedly turning on the heating control switch. Directly perform the heating end condition judgment process. When the heating state of the heating film is heating off, further determine the minimum temperature of the battery pack. When the minimum temperature of the battery pack reaches the battery pack heating start temperature, then it can be further determined whether to turn on the heating based on the heating start condition.

[0051] In another preferred embodiment, the heating start condition includes one of the following:

[0052] The lowest temperature of the battery pack is within a preset low temperature range and the minimum remaining power is greater than a first preset power.

[0053] The lowest temperature of the battery pack is greater than the upper limit of the preset low temperature range, and the minimum remaining power is greater than or equal to the second preset power, and the second preset power is less than the first preset power.

[0054] The lowest temperature of the battery pack is greater than the upper limit of the preset low temperature range, the minimum remaining power is less than the second preset power, and the charging current of the battery pack is greater than the first preset current value.

[0055] In an example, the preset low temperature range can be [-18℃, 0℃], -18℃ is the lower limit of the preset low temperature range, 0℃ is the upper limit of the preset low temperature range, the first preset power can be 8%, the second preset power can be 5%, the first preset current value can be 1A, and the first preset current value can be adjusted according to actual conditions.

[0056] Specific:

[0057] When the battery pack minimum temperature T min At [-18℃, 0℃], and the minimum remaining power SOC min When the temperature is ≥8%, it is confirmed that the operation information meets the heating start condition, the heating control switch is closed, and the heating film is turned on to heat the battery pack.

[0058] When the battery pack minimum temperature T min >0℃, and minimum remaining capacity SOC min ≥5%, it is confirmed that the operating information meets the heating start conditions, the heating control switch is closed, and the heating film is turned on to heat the battery pack.

[0059] When the battery pack minimum temperature T min >0℃, minimum remaining power SOC min <5%, and the battery pack charging current I 包 >1A.

[0060] As long as any one of the above three conditions is met, the heating control switch is closed and the heating film is turned on to heat the battery pack.

[0061] In another preferred embodiment, the operation information further includes voltage information and fault detection results, wherein the heating end condition includes:

[0062] The heating film function status is not enabled; the voltage information corresponding to the battery system meets the preset undervoltage condition; the battery system is in the shutdown process, in sleep mode or in the self-test process before power-on; the fault detection result indicates that the battery system has a fault; the external ambient temperature of the battery system is less than or equal to the lower limit of the preset low temperature range; the minimum temperature of the battery pack is greater than or equal to the first heating end temperature; the maximum temperature of the battery pack is greater than or equal to the second heating end temperature, and the second heating end temperature is greater than the first heating end temperature.

[0063] If the operating information meets any of the above conditions, the heating control switch is disconnected to stop heating the battery pack.

[0064] Specifically, the first heating end temperature may be 7°C, and the second heating end temperature may be 19°C.

[0065] The operation information also includes a heating film enable flag and a status flag corresponding to the battery system.

[0066] Specifically, if the heating film enable flag indicates that the heating film function state is not enabled, the heating control switch is disconnected to stop heating the battery pack.

[0067] If the status flag indicates that the battery system is in the shutdown process, the heating control switch is disconnected to stop heating the battery pack; if the status flag indicates that the battery system is in the sleep state, the heating control switch is disconnected to stop heating the battery pack; if the status flag indicates that the battery system is in the self-test process before power-on, the heating control switch is disconnected to stop heating the battery pack.

[0068] If the external ambient temperature AT corresponding to the battery system is ≤ -18°C, the heating control switch is disconnected to stop heating the battery pack.

[0069] If the minimum temperature of the battery pack is T min ≥7℃, the heating control switch is turned off to stop heating the battery pack; if the maximum temperature of the battery pack T max ≥19℃, the heating control switch is disconnected to stop heating the battery pack. This condition is applicable to the situation where the temperature difference collected by multiple temperature detection sensors is relatively large, making the heating process more accurate.

[0070] In the present application, the battery system also includes at least one voltage acquisition module, which is used to collect the cell voltage corresponding to each battery cell. The voltage information includes the cell voltage corresponding to each battery cell, the module voltage corresponding to the voltage acquisition module and the power supply voltage corresponding to the battery system. The module voltage is the sum of multiple cell voltages collected by the voltage acquisition module, and the power supply voltage is the sum of the cell voltages corresponding to all the battery cells in the battery pack.

[0071] Specifically, assuming that the battery system of the present application includes 10 battery cells a1~a10 and 2 voltage acquisition modules, each voltage sampling module can collect voltages corresponding to 5 battery cells. Then for one of the voltage acquisition modules b1, it collects voltages U1~U5 corresponding to battery cells a1~a5, and the other voltage acquisition module b2 collects voltages U6~U10 corresponding to battery cells a6~a10. Then the module voltage UA corresponding to the voltage acquisition module b1 is UA=U1+U2+U3+U4+U5, and the power supply voltage U=U1+U2+U3+U4+U5+U6+U7+U8+U9+U10.

[0072] Among them, the preset undervoltage conditions include:

[0073] Any cell voltage is less than or equal to the preset cell undervoltage value; the module voltage is less than or equal to the preset module undervoltage value; the power supply voltage is less than or equal to the preset power supply undervoltage value; any cell voltage is less than or equal to the preset cell shutdown voltage; the module voltage is less than or equal to the preset module shutdown voltage; the power supply voltage is less than or equal to the preset power supply shutdown voltage.

[0074] The preset cell undervoltage value corresponding to each battery cell is the same, the preset module undervoltage value = n × preset cell undervoltage value, where n represents the number of cell voltages that the voltage sampling module can collect, the preset power supply undervoltage value = N × preset cell undervoltage value, N represents the number of battery cells included in the battery pack, similarly, the preset module shutdown voltage = n × preset cell shutdown voltage, and the preset power supply shutdown voltage = N × preset power supply shutdown voltage.

[0075] That is to say, when any one of the above-mentioned preset undervoltage conditions is met, the heating control switch is disconnected to stop heating the battery pack.

[0076] In a preferred embodiment, the method further comprises:

[0077] Perform fault detection on the heating film in real time and generate fault detection results.

[0078] Among them, in the event of a failure of the heating film, a corresponding fault alarm needs to be issued according to the corresponding fault type to facilitate subsequent maintenance by the user.

[0079] Among them, the battery system also includes a Hall sensor for collecting the average current of the heating film. The heating film failures include heating film disconnection, heating film open circuit, heating control switch sticking and heating film reverse connection.

[0080] In a preferred embodiment, the heating film is fault-detected in the following manner:

[0081] Continuously collect multiple sampling reference voltages corresponding to the Hall sensor. If there are a continuous preset number of sampling reference voltages that are not in the standard reference voltage range, it is determined that the heating film is offline. If there are not a continuous preset number of sampling reference voltages that are not in the standard reference voltage range, it is determined that the heating film has not had a heating film offline failure.

[0082] When the heating film heating state is heating start, if the average current of the heating film is less than the second preset current value, it is determined that the heating film is open-circuited; if the average current of the heating film is greater than or equal to the second preset current value, it is determined that the heating film does not have a heating film open-circuit fault.

[0083] When the heating state of the heating film is heating off, if the average current of the heating film is greater than or equal to the third preset current value, it is determined that the heating control switch is stuck; if the average current of the heating film is less than the third preset current value, it is determined that the heating control switch is normal.

[0084] If the average current of the heating film is greater than the fourth preset current value, it is determined that the heating film is short-circuited; if the average current of the heating film is less than or equal to the fourth preset current value, it is determined that the heating film is not short-circuited.

[0085] If the average current of the heating film is less than the fifth preset current value, it is determined that the heating film is reversely connected. If the average current of the heating film is greater than or equal to the fifth preset current value, it is determined that the heating film is connected normally.

[0086] Specifically, the fourth preset current value may be 20A, and the fifth preset current value may be -0.5A.

[0087] In another preferred embodiment, the battery system also includes a Hall sensor for collecting the average current of the heating film, and the failure of the battery system includes a heating film failure, and the heating film failure includes a heating film disconnection, a heating film open circuit, a heating film short circuit and a heating film reverse connection.

[0088] In another specific embodiment, the failure of the battery system also includes the sticking of the heating control switch, wherein the method further includes: if the average current of the heating film is greater than the sixth preset current value, it is determined that the heating control switch is stuck, and the sixth preset current value can be set according to actual conditions.

[0089] See also Figure 2 , Figure 2 FIG. 1 shows a flow chart of another method for heating a battery pack provided in an embodiment of the present application. Figure 2 As shown, the method includes:

[0090] A1. Determine whether the heating film enabling state is enabled.

[0091] A2. If the heating film enabling state is enabled, the battery pack heating control process is started.

[0092] If the heating film enabling state is not enabled, step A5 is executed to issue a heating film enabling fault prompt, and no subsequent processing is performed.

[0093] A3. Determine whether the heating state of the heating film is heating off.

[0094] If the heating state of the heating film is heating start, step S400 is executed.

[0095] A4. If the heating state of the heating film is heating off, determine the minimum temperature of the battery pack T min Is it less than or equal to the battery pack opening temperature?

[0096] If the minimum temperature of the battery pack is T min If the temperature is less than or equal to the battery pack opening temperature, step S200 is executed.

[0097] If the minimum temperature of the battery pack is T min If the temperature is greater than the battery pack opening temperature, step S400 is executed.

[0098] See also Figure 3 , Figure 3FIG. 2 shows another flow chart of a battery pack heating method provided in an embodiment of the present application. Figure 3 As shown, step S200 includes:

[0099] A201, determine the minimum temperature T of the battery pack min Is it in [-18℃, 0℃] and SOC min ≥8%.

[0100] If T min At [-18℃, 0℃] and SOC min ≥8%, execute step A205 and control the heating control switch to close.

[0101] A202, if T min Not in [-18℃, 0℃] or SOC min <8%, then judge T min Is it greater than 0℃ and SOC min ≥5%.

[0102] If T min >0℃, and SOC min ≥5%, execute step S205.

[0103] A203, if T min ≤0℃, or SOC min <5%, then judge T min Is it greater than 0℃ and SOC min <5%, and I 包 >1A.

[0104] If T min >0℃, and SOC min <5%, and I 包 >1A, execute step S205.

[0105] A204, if T min ≤0℃, or SOC min ≥5%, or I 包 ≥1A, the heating control switch is disconnected.

[0106] After the heating control switch is controlled to be turned off or after step S205 is executed, step S400 is executed.

[0107] See also Figure 4 , Figure 4 FIG. 3 shows another flow chart of a battery pack heating method provided in an embodiment of the present application. Figure 4 As shown, step S400 includes:

[0108] A401. Determine whether the heating film enabling state is enabled.

[0109] A402. If the heating film enabling state is enabled, determine whether the voltage information meets the preset undervoltage condition.

[0110] If the heating film enabling state is not enabled, execute step A403 to control the heating control switch to be turned off.

[0111] A404: If the voltage information does not meet the preset undervoltage condition, determine whether the battery system is in the shutdown process.

[0112] If the battery system is in the shutdown process, execute step A403.

[0113] A405. If the battery system is not in the shutdown process, determine whether the battery system is in a dormant state.

[0114] If the battery system is in a dormant state, step A403 is executed.

[0115] A406. If the battery system is not in sleep mode, determine whether the battery system is in the self-check process before powering on.

[0116] If the battery system is in the pre-power-on self-test process, execute step A403.

[0117] A407. If the battery system is not in the pre-startup self-test process, determine whether the battery system is faulty.

[0118] If the battery system fails, execute step A403.

[0119] A408. If the battery system has not failed, determine whether the external ambient temperature AT is less than or equal to -18°C.

[0120] If AT≤-18°C, execute step A403.

[0121] A409, if AT>-18℃, then determine the minimum temperature of the battery pack T min Is it greater than or equal to 7℃?

[0122] If T min ≥7℃, execute step A403.

[0123] A410, if T min <7℃, the maximum temperature of the battery pack is determined to be T max Is it greater than or equal to 19℃?

[0124] If T max ≥19°C, execute step A403.

[0125] If T max <19°C, return to step A2.

[0126] See also Figure 5 , Figure 5 FIG4 shows another flow chart of a battery pack heating method provided in an embodiment of the present application. Figure 5 As shown, the fault detection steps include:

[0127] A801, determine whether the heating film is offline.

[0128] See also Figure 6 , Figure 6 FIG5 shows another flowchart of a battery pack heating method provided by an embodiment of the present application. Figure 6 As shown, step A801 ​​includes:

[0129] A8011, collect the sampling reference voltage corresponding to the Hall sensor.

[0130] A8012, determine whether the sampling reference voltage is within 2.5V±10%.

[0131] A8013. If the sampled reference voltage is not at 2.5V±10%, the voltage error count is C+1.

[0132] A8014. Determine whether the voltage error count C is greater than a preset number.

[0133] A8015: If the voltage acquisition count is greater than the preset number, it is determined that the heating film is offline and the voltage error count is cleared.

[0134] If the voltage acquisition count is less than or equal to the preset number, it returns to execute A8011.

[0135] A8016: If the sampling reference voltage is at 2.5V±10%, the voltage error count is reset to zero to determine that there is no heating film disconnection.

[0136] A802: If the heating film is offline, the heating film offline alarm will be executed.

[0137] A803. If the heating film does not exist and the heating film is offline, determine whether the heating film is open circuited.

[0138] Specifically, first determine whether the heating state of the heating film is heating start. When the heating state of the heating film is heating start, determine whether the average current of the heating film is less than 1A. If the average current of the heating film is less than 1A, it is determined that the heating film is open circuited. If the average current of the heating film is greater than or equal to 1A, it is determined that the heating film is not open circuited.

[0139] A804: If the heating film is open circuit, the heating film open circuit alarm will be executed.

[0140] A805. If there is no open circuit in the heating film, determine whether there is any adhesion in the heating film relay.

[0141] If the heating state of the heating film is heating off, determine whether the average current of the heating film is greater than or equal to 1A. If the average current of the heating film is greater than or equal to 1A, determine that the heating film relay is stuck. If the average current of the heating film is less than 1A, determine that the heating film relay is not stuck.

[0142] A806: If the heating film relay is stuck, the relay sticking alarm will be executed.

[0143] A807. If there is no heating film relay adhesion, determine whether there is a heating film short circuit.

[0144] If the average current of the heating film is greater than 20A, it is determined that the heating film is short-circuited.

[0145] A808: If there is a heating film short circuit, a heating film short circuit alarm will be issued.

[0146] A809. If there is no short circuit of the heating film, determine whether the heating film is reversely connected.

[0147] If the average current of the heating film is less than -0.5A, it is determined that the heating film is reversely connected.

[0148] A810: If the heating film is reversely connected, the heating film reverse connection alarm will be executed.

[0149] If the heating film is not reversely connected, the process returns to step A2.

[0150] Based on the same application concept, a battery pack heating device corresponding to the battery pack heating method provided in the above embodiment is also provided in the embodiment of the present application. Since the principle of solving the problem by the device in the embodiment of the present application is similar to the battery pack heating method in the above embodiment of the present application, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be repeated.

[0151] See also Figure 7 , Figure 7 FIG. 1 is a schematic diagram showing the structure of a battery pack heating device provided in an embodiment of the present application. Figure 7 As shown, it is applied to a battery system, the battery system includes a battery pack, a heating film and a heating control switch, the heating film covers the battery pack, a plurality of temperature detection sensors are arranged inside the battery pack, the heating film is connected to the heating control switch, and the device includes:

[0152] The acquisition module 600 is used to acquire the operation information corresponding to the battery pack;

[0153] A first judgment module 610 is used to judge whether the operation information meets the heating start condition;

[0154] A heating start module 620 is used to close the heating control switch and start the heating film to heat the battery pack if the operation information meets the heating start condition;

[0155] The second judgment module 630 is used to judge whether the operation information meets the heating end condition if the operation information does not meet the heating start condition;

[0156] The heating shut-off module 640 is used to disconnect the heating control switch and shut down the heating of the battery pack by the heating film if the operation information meets the heating end condition.

[0157] Based on the same application idea, please refer to Figure 8 , Figure 8 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application is shown, wherein the electronic device 900 comprises: a processor 910, a memory 920 and a bus 930, wherein the memory 920 stores machine-readable instructions executable by the processor 910, and when the electronic device 900 is running, the processor 910 communicates with the memory 920 via the bus 930, and the machine-readable instructions are executed by the processor 910 when running, such as the steps of the battery pack heating method provided in any of the above embodiments.

[0158] Based on the same application concept, an embodiment of the present application also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the battery pack heating method provided in the above embodiment are executed.

[0159] Those skilled in the art can clearly understand that, for the convenience and simplicity of description, the specific working process of the system and device described above can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here. In the several embodiments provided in the present application, it should be understood that the disclosed system, device and method can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0160] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0161] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0162] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a non-volatile computer-readable storage medium that is executable by a processor. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, etc., various media that can store program codes.

[0163] The above are only specific implementations 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 changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A battery pack heating method, characterized in that: Applied to a battery system, the battery system includes a battery pack, a heating film and a heating control switch, the heating film covers the battery pack, a plurality of temperature detection sensors are arranged inside the battery pack, and the heating film is connected to the heating control switch. Wherein, the method comprises: Collect the operating information corresponding to the battery pack; Determining whether the operation information meets the heating start condition; If the operation information satisfies the heating start condition, the heating control switch is closed to start the heating film to heat the battery pack; If the operation information does not meet the heating start condition, determining whether the operation information meets the heating end condition; If the operation information satisfies the heating end condition, the heating control switch is disconnected to turn off the heating of the battery pack by the heating film.

2. The method according to claim 1, characterized in that The operation information also includes the heater film enabling state, the heater film heating state and the battery pack minimum temperature. After collecting the operating information corresponding to the battery pack, the method further includes: Determining whether the heating film enabling state is enabled; If the enabling state of the heating film is enabled, obtaining the heating state of the heating film; If the heating state of the heating film is heating start, determining whether the operation information satisfies a heating end condition, and if the operation information satisfies the heating end condition, disconnecting the heating control switch to turn off the heating film for heating the battery pack; If the heating state of the heating film is heating off, determining whether the lowest temperature of the battery pack is less than or equal to the battery pack heating start temperature; If the battery pack minimum temperature is less than or equal to the battery pack heating start temperature, determining whether the operation information meets the heating start condition; If the heating film enabling state is disabled, a heating film enabling fault prompt is given without subsequent processing.

3. The method according to claim 2, characterized in that The operation information also includes the remaining power of each battery cell and the charging current of the battery pack. Wherein, the heating start condition includes one of the following: The lowest temperature of the battery pack is within a preset low temperature range and the minimum remaining power is greater than a first preset power; The lowest temperature of the battery pack is greater than the upper limit of the preset low temperature range, and the minimum remaining power is greater than or equal to the second preset power, and the second preset power is less than the first preset power; The lowest temperature of the battery pack is greater than an upper limit of a preset low temperature range, the minimum remaining power is less than a second preset power, and the charging current of the battery pack is greater than a first preset current value.

4. The method according to claim 2, characterized in that: The operation information also includes voltage information and fault detection results. Wherein, the heating end condition includes: The heating film enabling state is disabled; The voltage information corresponding to the battery system meets the preset undervoltage condition; The battery system is in the process of shutting down, in sleep mode, or in the process of self-test before starting up; The fault detection result indicates that a battery system fault has occurred; The external ambient temperature of the battery system is less than or equal to the lower limit of the preset low temperature range; The lowest temperature of the battery pack is greater than or equal to the first heating end temperature; The maximum temperature of the battery pack is greater than or equal to a second heating end temperature, and the second heating end temperature is greater than the first heating end temperature.

5. The method according to claim 4, characterized in that The battery system further includes at least one voltage acquisition module, the voltage acquisition module is used to acquire the cell voltage corresponding to each cell, the voltage information includes the cell voltage corresponding to each cell, the module voltage corresponding to the voltage acquisition module and the power supply voltage corresponding to the battery system, the module voltage is the sum of multiple cell voltages acquired by the voltage acquisition module, and the power supply voltage is the sum of cell voltages corresponding to all cells in the battery pack, Wherein, the preset undervoltage condition includes: The voltage of any battery cell is less than or equal to the preset battery cell undervoltage value; The module voltage is less than or equal to a preset module undervoltage value; The power supply voltage is less than or equal to a preset power supply undervoltage value; The voltage of any battery cell is less than or equal to the preset battery cell shutdown voltage; The module voltage is less than or equal to a preset module shutdown voltage; The power supply voltage is less than or equal to a preset power supply shutdown voltage.

6. The method according to claim 4, characterized in that The method further comprises: Perform fault detection on the heating film in real time to generate a fault detection result.

7. The method according to claim 6, characterized in that The battery system also includes a Hall sensor for collecting the average current of the heating film. The heating film failure includes heating film disconnection, heating film open circuit, heating film reverse connection and heating control switch adhesion. Wherein, the heating film is fault-detected in the following manner: Continuously collecting multiple sampling reference voltages corresponding to the Hall sensor, if there are a preset number of consecutive sampling reference voltages that are not within the standard reference voltage range, it is determined that the heating film is offline; When the heating state of the heating film is heating start, if the average current of the heating film is less than the second preset current value, it is determined that the heating film is open circuit; When the heating state of the heating film is heating off, if the average current of the heating film is greater than or equal to a third preset current value, it is determined that the heating control switch is stuck; If the average current of the heating film is greater than a fourth preset current value, it is determined that the heating film is short-circuited; If the average current of the heating film is less than the fifth preset current value, it is determined that the heating film is reversely connected.

8. A battery heating device, applied to a battery system, the battery system comprising a battery pack, a heating film and a heating control switch, the heating film covering the battery pack, a plurality of temperature detection sensors being arranged inside the battery pack, the heating film being connected to the heating control switch, characterized in that: The device comprises: A collection module, used to collect the operating information corresponding to the battery pack; A first judgment module, used to judge whether the operation information meets the heating start condition; A heating start module, configured to close the heating control switch and start the heating film to heat the battery pack if the operation information meets the heating start condition; A second judgment module is used to judge whether the operation information meets the heating end condition if the operation information does not meet the heating start condition; The heating shut-off module is used to disconnect the heating control switch and shut down the heating of the battery pack by the heating film if the operation information meets the heating end condition.

9. An electronic device, characterized in that: include: A processor, a memory and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor and the memory communicate through the bus, and the machine-readable instructions are executed by the processor to execute the steps of the battery pack heating method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the battery pack heating method according to any one of claims 1 to 7 are executed.

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