Battery control method, management system, battery system, device, medium and product

Abstract

The present disclosure discloses a battery control method, management system, battery system, device, medium, and product, wherein the method includes: obtaining a target thermal condition of the battery during the charge and discharge process; in response to the battery's current health status value decaying to below a first state threshold, adjusting the discharge lower limit of the battery in the charge and discharge interval based on the target thermal condition and the thermal state of the battery during the charge and discharge process to obtain a target discharge lower limit; and performing a first-stage charge and discharge control on the battery based on the target discharge lower limit. In the present disclosure, after the battery's charge and discharge interval decays, the battery's available remaining capacity can be increased while reducing damage to the battery and slowing the battery's aging rate.

Description

Technical Field

[0001] The present disclosure relates to, but is not limited to, the field of battery equipment technology, and in particular to a battery control method, management system, battery system, equipment, medium, and product. Background Art

[0002] In battery design, the low voltage range of the battery's charge and discharge interval has a greater risk of gas and heat generation. In related technologies, the use of the low voltage range of the battery's charge and discharge interval is restricted, which makes the battery capacity cannot be fully utilized, resulting in redundancy and waste. Summary of the Invention

[0003] In view of this, the embodiments of the present disclosure provide at least a battery control method, a management system, a battery system, a device, a medium, and a product.

[0004] The technical solution of the embodiment of the present disclosure is implemented as follows:

[0005] An embodiment of the present disclosure provides a battery control method, including:

[0006] Obtain the target thermal conditions of the battery during the charging and discharging process;

[0007] In response to the current state of health value of the battery decaying below a first state threshold, adjusting a lower discharge limit of the battery in a charge and discharge interval based on a target thermal condition and a thermal state of the battery during a charge and discharge process to obtain a target lower discharge limit;

[0008] Based on the target lower discharge limit, the battery is charged and discharged in the first stage.

[0009] In the disclosed embodiment, the target thermal condition of the battery during the charge and discharge process is first obtained; secondly, when the current health state value of the battery decays to below the first state threshold, the lower discharge limit of the battery in the charge and discharge interval is adjusted according to the target thermal condition and the thermal state of the battery during the charge and discharge process to obtain the target discharge lower limit; finally, the battery is subjected to the first stage of charge and discharge control according to the target discharge lower limit. In this way, when it is detected that the current health state value decays to below the first state threshold, the thermal state of the battery during the charge and discharge process and the target thermal condition are comprehensively considered, and the lower discharge limit of the battery in the charge and discharge interval is adjusted, so that after the charge and discharge interval of the battery decays, the available remaining capacity of the battery is increased while reducing damage to the battery and slowing down the aging rate of the battery.

[0010] In some embodiments, based on the target thermal condition and the thermal state of the battery during the charge and discharge process, the discharge lower limit in the charge and discharge interval of the battery is adjusted to obtain the target discharge lower limit, including: lowering the discharge lower limit to a first candidate lower limit; performing a second-stage charge and discharge control on the battery based on the first candidate lower limit, and monitoring the thermal state of the battery during the second-stage charge and discharge control process; in response to the thermal state of the battery during the second-stage charge and discharge control process satisfying the target thermal condition, determining the first candidate lower limit as the target discharge lower limit.

[0011] In the above embodiment, the discharge lower limit is lowered to the first candidate lower limit; the battery is subjected to a second phase of charge and discharge control based on the first candidate lower limit, and the thermal state of the battery during the second phase of charge and discharge control is monitored; if the thermal state of the battery during the second phase of charge and discharge control meets the target thermal condition, the first candidate lower limit is determined as the target discharge lower limit. Thus, if the thermal condition meets the target thermal condition, the first candidate lower limit is determined as the target discharge lower limit, thereby increasing the battery's charge and discharge range.

[0012] In some embodiments, the thermal state of the battery during the second stage of charge and discharge control satisfies the target thermal condition, including at least one of the following: when the target thermal condition includes a target heat production condition and the thermal state includes a heat production state, the heat production state of the battery during the second stage of charge and discharge control satisfies the target heat production condition; when the target thermal condition includes a target stress condition and the thermal state includes a stress state, the stress state of the battery during the second stage of charge and discharge control satisfies the target stress condition; when the target thermal condition includes a target volume condition and the thermal state includes a volume state, the volume state of the battery during the second stage of charge and discharge control satisfies the target volume condition.

[0013] In the above embodiment, when the target thermal condition includes a target heat generation condition and the thermal state includes a heat generation condition, the heat generation condition of the battery during the second stage of charge and discharge control satisfies the target heat generation condition; when the target thermal condition includes a target stress condition and the thermal state includes a stress state, the stress state of the battery during the second stage of charge and discharge control satisfies the target stress condition; and when the target thermal condition includes a target volume condition and the thermal state includes a volume state, the volume state of the battery during the second stage of charge and discharge control satisfies the target volume condition. In this way, whether the heat generation condition, stress state, and volume state satisfy their corresponding target heat generation condition, target stress condition, and target volume condition is considered separately, thereby improving the accuracy of determining whether the thermal state satisfies the target thermal condition.

[0014] In some embodiments, the target thermal condition includes a target change condition of the thermal state; in response to the thermal state of the battery during the second stage of charge and discharge control satisfying the target thermal condition, the first candidate lower limit is determined as the target discharge lower limit, including: in response to the degree of change of the thermal state of the battery during the second stage of charge and discharge control satisfying the target change condition, the first candidate lower limit is determined as the target discharge lower limit.

[0015] In the above embodiment, if the degree of change in the battery's thermal state during the second stage of charge and discharge control meets the target change condition, the first candidate lower limit is determined as the target discharge lower limit. Since the battery's thermal state is a cumulative process, the satisfaction of the condition can be determined based on the amount of change in the thermal state, allowing accurate determination of the thermal state change.

[0016] In some embodiments, the degree of change of the thermal state of the battery during the second stage of charge and discharge control satisfies the target change condition, including at least one of the following: when the target change condition includes a target heat production change condition and the degree of change of the thermal state includes a heat production change degree, the degree of change of the heat production of the battery during the second stage of charge and discharge control satisfies the target heat production change condition; when the target change condition includes a target stress change condition and the degree of change of the thermal state includes a stress change degree, the degree of change of the stress of the battery during the second stage of charge and discharge control satisfies the target stress change condition; when the target change condition includes a target volume change condition and the degree of change of the thermal state includes a volume change degree, the degree of change of the volume of the battery during the second stage of charge and discharge control satisfies the target volume change condition.

[0017] In the above embodiment, when the target change condition includes a target heat generation change condition and the degree of change in the thermodynamic state includes the degree of heat generation change, the degree of heat generation change of the battery during the second stage of charge and discharge control satisfies the target heat generation change condition; when the target change condition includes a target stress change condition and the degree of change in the thermodynamic state includes the degree of stress change, the degree of stress change of the battery during the second stage of charge and discharge control satisfies the target stress change condition; when the target change condition includes a target volume change condition and the degree of change in the thermodynamic state includes the degree of volume change, the degree of volume change of the battery during the second stage of charge and discharge control satisfies the target volume change condition. In this way, whether the degree of heat generation change, the degree of stress change, and / or the degree of volume change satisfy their respective corresponding target heat generation change conditions, target stress change conditions, and target volume change conditions is separately considered, thereby improving the accuracy of determining whether the degree of change in the thermodynamic state satisfies the target change conditions.

[0018] In some embodiments, the method further includes: determining a first rate of change of the thermal state of the battery during the third stage of charge and discharge control; the third stage is a stage of charge and discharge control of the battery before the health state value decays to a first state threshold; determining a second rate of change of the thermal state of the battery during the second stage of charge and discharge control; when the ratio of the second rate of change to the first rate of change is not greater than the first ratio threshold, determining that the degree of change of the thermal state of the battery during the second stage of charge and discharge control meets the target change condition.

[0019] In the above embodiment, the third stage is a stage in which the battery is subjected to charge and discharge control before the health state value decays to the first state threshold. If the ratio of the second rate of change of the thermal state of the battery during the second stage of charge and discharge control to the first rate of change of the thermal state during the third stage of charge and discharge control is not greater than the first ratio threshold, it is determined that the degree of change of the thermal state of the battery during the second stage of charge and discharge control meets the target change condition. In this way, the relationship between the degree of change of the thermal state of the battery during the second stage of charge and discharge control and the degree of change of the thermal state of the battery during the third stage of charge and discharge control can be determined based on the ratio of the second rate of change to the first rate of change, thereby determining whether there is a risk of damage to the battery, that is, whether the current degree of change of the thermal state meets the target change condition.

[0020] In some embodiments, based on the target thermal condition and the thermal state of the battery during the charging and discharging process, the discharge lower limit in the charging and discharging interval of the battery is adjusted to obtain the target discharge lower limit, and also includes: in response to the thermal state of the battery during the first stage of charging and discharging control not meeting the target thermal condition, determining the reference discharge lower limit as the target discharge lower limit, and the reference discharge lower limit is higher than the first candidate lower limit.

[0021] In the above embodiment, in response to the battery's thermal state not meeting the target thermal condition during the first stage of charge and discharge control, a reference lower discharge limit is determined as the target lower discharge limit, and the reference lower discharge limit is higher than the first candidate lower limit. Thus, when the thermal state does not meet the target thermal condition, the reference lower discharge limit, which is higher than the first candidate lower limit, is determined as the target lower discharge limit, thereby reducing damage to the battery caused by the thermal condition.

[0022] In some embodiments, adjusting the discharge lower limit to the first candidate lower limit includes: determining an adjustment step size of the discharge lower limit; and adjusting the discharge lower limit to the first candidate lower limit based on the adjustment step size.

[0023] In the above embodiment, the adjustment step size of the discharge lower limit is determined, and based on the adjustment step size, the discharge lower limit is adjusted down to the first candidate lower limit. In this way, the discharge lower limit can be adjusted down to a suitable first candidate lower limit according to a suitable adjustment step size.

[0024] In some embodiments, determining the adjustment step size of the lower discharge limit includes: determining the adjustment step size of the lower discharge limit based on a current health state value of the battery; wherein the adjustment step size is inversely proportional to the current health state value.

[0025] In the above embodiment, the adjustment step size of the lower discharge limit is determined based on the battery's current state of health value; the adjustment step size is inversely proportional to the current state of health value. Thus, when the state of health value is high, greater consideration is given to minimizing damage to the battery. Therefore, a smaller adjustment step size can be set to reduce damage to the battery caused by excessively lowering the lower discharge limit, thereby slowing battery aging. Conversely, when the state of health value is low, greater consideration is given to increasing the battery's remaining capacity. Therefore, a larger adjustment step size is set to increase the battery's remaining capacity. This allows for a balance between increasing the battery's remaining capacity and minimizing damage as the battery's state of health continues to decline, thereby improving the battery's overall performance during use.

[0026] An embodiment of the present disclosure provides a battery management system, the battery management system comprising:

[0027] An acquisition module is used to obtain the target thermal conditions of the battery during the charging and discharging process;

[0028] an adjustment module, configured to adjust, in response to the current health state value of the battery decaying below a first state threshold, a lower discharge limit of the battery in a charge and discharge interval based on a target thermal condition and a thermal state of the battery during a charge and discharge process, to obtain a target lower discharge limit;

[0029] The control module is used to control the charge and discharge of the battery in the first stage based on the target lower discharge limit.

[0030] An embodiment of the present disclosure provides a battery system, including a battery and the above-mentioned battery management system.

[0031] An embodiment of the present disclosure provides a computer device including a memory and a processor, wherein the memory stores a computer program that can be run on the processor, and when the processor executes the program, some or all of the steps in the above method are implemented.

[0032] An embodiment of the present disclosure provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, some or all of the steps in the above method are implemented.

[0033] An embodiment of the present disclosure provides a computer program product, including a computer program or instructions. When the computer program or instructions are executed by a processor, some or all of the steps in the above method are implemented.

[0034] It should be understood that the above general description and the following detailed description are merely exemplary and explanatory, and are not intended to limit the technical solutions of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The accompanying drawings herein are incorporated into and constitute a part of the specification. These drawings illustrate embodiments consistent with the present disclosure and, together with the specification, are used to explain the technical solutions of the present disclosure.

[0036] Figure 1 A schematic diagram of an implementation flow of a battery control method provided in an embodiment of the present disclosure;

[0037] Figure 2 A schematic diagram of the structure of a battery management system provided in an embodiment of the present disclosure;

[0038] Figure 3 A schematic diagram of the structure of a battery system provided in an embodiment of the present disclosure;

[0039] Figure 4 A schematic diagram of aging capacity retention rates at different discharge lower limits provided by an embodiment of the present disclosure;

[0040] Figure 5 A schematic diagram of a test result of dynamically adjusting the lower discharge limit and a control group test result provided by an embodiment of the present disclosure;

[0041] Figure 6 A schematic diagram of a hardware entity of a computer device provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solutions and advantages of the present disclosure clearer, the technical solutions of the present disclosure are further elaborated in detail below with reference to the accompanying drawings and embodiments. The described embodiments should not be regarded as limiting the present disclosure. All other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present disclosure.

[0043] In the following description, reference is made to “some embodiments”, which describes a subset of all possible embodiments, but it will be understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0044] The terms "first / second / third" involved are merely used to distinguish similar objects and do not represent a specific ordering of the objects. It is understandable that "first / second / third" can be interchanged with a specific order or sequence where permitted so that the embodiments of the present disclosure described herein can be implemented in an order other than that illustrated or described herein.

[0045] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present disclosure pertains. The terms used herein are for the purpose of describing the present disclosure only and are not intended to limit the present disclosure.

[0046] The present disclosure provides a battery control method. Figure 1 A schematic diagram of a battery control method according to an embodiment of the present disclosure is provided. Figure 1 As shown, the method includes the following steps S101 to S103:

[0047] Step S101: obtaining target thermal conditions of the battery during the charging and discharging process;

[0048] In some embodiments, the target thermodynamic condition may include, but is not limited to, at least one of a target heat production condition, a target stress condition, a target volume condition, and the like.

[0049] The target heat generation condition is the condition that the battery's heat generation state must meet during the charge and discharge process to ensure safe battery operation. This is the upper heat generation threshold set during the battery charge and discharge control process, taking into account the damage to the battery caused by heat generation. The upper heat generation threshold can be preset by those skilled in the art based on actual circumstances and is not limited in the present disclosure. Here, the battery's heat generation state may include the heat generated by the battery's DC internal resistance.

[0050] The target stress condition is the stress condition that the battery must meet to ensure safe battery operation during the charge and discharge process. This refers to the upper stress threshold set during the battery charge and discharge control process, taking into account the damage to the battery caused by stress. The upper stress threshold can be preset by those skilled in the art based on actual conditions and is not limited in the present disclosure. Here, the stress state may include the expansion force generated by gas production due to electrochemical reactions in the battery.

[0051] The target volume condition is the condition that the battery's volume state satisfies when the battery operates safely during the charging and discharging process, that is, the volume upper limit threshold is set in consideration of the damage to the battery caused by volume expansion during the battery charging and discharging control process. The volume upper limit threshold can be pre-set by those skilled in the art based on actual conditions, and the embodiments of the present disclosure do not limit this.

[0052] Step S102: In response to the current state of health value of the battery decaying below a first state threshold, adjusting a lower discharge limit of the battery in a charge / discharge interval based on a target thermal condition and a thermal state of the battery during charge / discharge to obtain a target lower discharge limit;

[0053] Here, the State of Health (SOH) is an important indicator for evaluating battery performance and service life. It is the ratio of the maximum available capacity that can be discharged by the battery when it is fully charged to its initial capacity or rated capacity.

[0054] The first state threshold may be preset by those skilled in the art according to actual conditions, and the embodiments of the present disclosure do not limit this.

[0055] In some embodiments, the first state threshold can generally be set to 85% to 90%. Since the battery attenuates less and the charge and discharge range is relatively large when the health state value is above the first state threshold, in order to reduce the damage to the battery caused by lowering the discharge lower limit, the discharge lower limit can be adjusted when the health state value decays below the first state.

[0056] In some embodiments, the battery's charge and discharge range is an open voltage range, not the battery's theoretically usable voltage range. For example, if the battery's theoretically usable voltage lower limit is 2.0V, the discharge lower limit can be set to 2.6V, but in some scenarios, the battery can continue to discharge to 2.0V.

[0057] The battery's charge and discharge interval can also be an open charge and discharge state of charge (SOC) interval. For example, if the theoretically available SOC lower limit of the battery is 0%, the SOC interval can be set to 30% to 100%, that is, the discharge lower limit is 30%, but in some scenarios, discharge can continue to 20% SOC.

[0058] In some embodiments, if the lower discharge limit of all batteries is set to 2.6V, the use of the low voltage range is directly restricted, while in some scenarios the battery can continue to be discharged to 2V. This means that the capacity of the lithium iron phosphate battery cannot be fully utilized, resulting in redundancy and waste. Not all batteries will produce gas and heat when they age, so the lower discharge limit can be lowered by detecting the gas and heat production of the battery.

[0059] In some embodiments, in order not to damage the performance of the battery, a portion of the low voltage range can be restricted and unavailable, that is, the lowest threshold value at which the lower discharge limit can be adjusted is determined. When the lowest threshold value is reached, the adjustment of the lower discharge limit is completed. For example, the initial lower discharge limit of the battery is 2.6V, which can be adjusted to a minimum of 2V.

[0060] In some embodiments, the thermodynamic state may include, but is not limited to, at least one of a heat generation state, a stress state, a volume state, and the like.

[0061] In some embodiments, during the charge and discharge process, the battery is more likely to generate heat and gas during the low voltage range of the charge and discharge interval, and its volume increases due to expansion. Gas and heat generation are cumulative processes. If excessive gas and heat generation accumulates, it will affect the performance, safety, and service life of the battery. Therefore, when adjusting the lower discharge limit, the target thermal conditions and the thermal state of the battery during the charge and discharge process should be comprehensively considered.

[0062] In some embodiments, if the lower discharge limit in the charge and discharge interval is lowered when the health status value is large, the battery performance may decline faster due to gas and heat production. Therefore, after the battery decays below the first state threshold, the lower discharge limit is adjusted by comprehensively considering the target thermal conditions and the thermal state of the battery during the charge and discharge process.

[0063] Step S103: Based on the target lower discharge limit, the battery is controlled to perform the first stage of charge and discharge.

[0064] Here, the first stage is a stage in which, after the adjustment of the discharge lower limit is completed, the obtained target discharge lower limit is used as the discharge lower limit to control the charge and discharge of the battery.

[0065] In some embodiments, two cells with good consistency are selected, namely cell 1 and cell 2, for testing, wherein cell 1 dynamically adjusts the lower limit of discharge according to the above method and performs charge and discharge control; cell 2 does not adjust the lower limit of discharge and performs charge and discharge control, such as Figure 5 As shown, under the same number of cycles, the health status value of battery cell 1 is greater than that of battery cell 2. Therefore, it can be concluded that adjusting the lower discharge limit can slow down the aging rate of the battery.

[0066] The embodiments of the present disclosure do not limit the chemical system of the above-mentioned battery. For example, the battery may include but is not limited to at least one of a lithium iron phosphate battery, a ternary lithium battery, a lithium manganese oxide battery, a lithium cobalt oxide battery, a nickel-metal hydride battery, and the like.

[0067] In some embodiments, the adjustment of the discharge lower limit is gradually adjusted according to the adjustment step size. For example, the discharge lower limit is lowered to a first candidate lower limit; in the process of performing charge and discharge control according to the first candidate lower limit, when the thermal state meets the target thermal condition, the current discharge lower limit is determined to be the first candidate lower limit; the current discharge lower limit is further lowered to a second candidate lower limit according to the current discharge lower limit and the adjustment step size; in the process of performing charge and discharge control according to the second candidate lower limit, when the thermal state meets the target thermal condition, the current discharge lower limit is determined to be the second candidate lower limit; the discharge lower limit is continued to be adjusted until it is adjusted to the lowest threshold value of the adjustable discharge lower limit, thereby completing the adjustment of the discharge lower limit.

[0068] In the disclosed embodiment, the target thermal condition of the battery during the charge and discharge process is first obtained; secondly, when the current health state value of the battery decays to below the first state threshold, the lower discharge limit of the battery in the charge and discharge interval is adjusted according to the target thermal condition and the thermal state of the battery during the charge and discharge process to obtain the target discharge lower limit; finally, the battery is subjected to the first stage of charge and discharge control according to the target discharge lower limit. In this way, when it is detected that the current health state value decays to below the first state threshold, the thermal state of the battery during the charge and discharge process and the target thermal condition are comprehensively considered, and the lower discharge limit of the battery in the charge and discharge interval is adjusted, so that after the charge and discharge interval of the battery decays, the available remaining capacity of the battery is increased while reducing damage to the battery and slowing down the aging rate of the battery.

[0069] Among them, adjusting the lower discharge limit can slow down the aging rate of the battery. The reason is that when the negative electrode potential of the battery is low (that is, the lower discharge limit of the battery is low), the main reaction of the negative electrode solid electrolyte interface film (Solid Electrolyte Interphase, SEI) changes, generating a denser SEI film component, which effectively slows down the reaction rate of the electrolyte, lithium ions and the negative electrode. Therefore, lowering the lower discharge limit can slow down the aging rate of the battery.

[0070] In some embodiments, the above step S102 may include the following steps S111 to S113:

[0071] Step S111: lowering the discharge lower limit to a first candidate lower limit;

[0072] Here, the first candidate lower limit is determined according to the current discharge lower limit and the adjustment step size of the discharge lower limit.

[0073] Step S112: performing a second-stage charge and discharge control on the battery based on the first candidate lower limit, and monitoring the thermal state of the battery during the second-stage charge and discharge control process;

[0074] Here, the second stage is a stage in which the battery is controlled to be charged and discharged using the first candidate lower limit as the discharge lower limit during the process of adjusting the discharge lower limit.

[0075] In some embodiments, the discharge lower limit is first lowered to a first candidate lower limit, and the battery is charged and discharged with the first candidate lower limit as the discharge lower limit. During the second stage of charge and discharge control of the battery, the thermal state of the battery is monitored in real time, and whether the target thermal conditions are met is determined based on the detected thermal state to determine whether the battery can operate safely with the first candidate lower limit as the discharge lower limit.

[0076] Step S113 : In response to the thermal state of the battery in the second stage of charge and discharge control satisfying the target thermal condition, determining the first candidate lower limit as the target discharge lower limit.

[0077] In some embodiments, during the second stage of charge and discharge control of the battery, when the thermal state always satisfies the target thermal condition, the first candidate lower limit is determined as the target discharge lower limit.

[0078] In some embodiments, after each time the discharge lower limit is lowered to the first candidate lower limit, the battery is subjected to a second stage of charge and discharge control. During the charge and discharge control process, the thermal state of the battery is monitored in real time. If the thermal state meets the target thermal condition, the first candidate lower limit is determined as the target discharge lower limit. Here, the target discharge lower limit is not lower than the lowest discharge lower limit threshold.

[0079] In the disclosed embodiment, the discharge lower limit is lowered to a first candidate lower limit; the battery is subjected to a second phase of charge and discharge control based on the first candidate lower limit, and the thermal state of the battery during the second phase of charge and discharge control is monitored; if the thermal state of the battery during the second phase of charge and discharge control meets the target thermal condition, the first candidate lower limit is determined as the target discharge lower limit. Thus, if the thermal condition meets the target thermal condition, the first candidate lower limit is determined as the target discharge lower limit, thereby increasing the battery's charge and discharge range.

[0080] In some embodiments, the above step S113 may include at least one of the following steps S121 to S123:

[0081] Step S121: when the target thermal condition includes a target heat generation condition and the thermal state includes a heat generation state, the heat generation state of the battery during the second stage of charge and discharge control satisfies the target heat generation condition;

[0082] In some embodiments, when the heat generated by the battery during the second stage of charge and discharge control is not greater than the heat represented by the target heat generation condition, it is determined that the heat generation state of the battery during the second stage of charge and discharge control meets the target heat generation condition.

[0083] In some embodiments, when the temperature of the battery during the second stage of charge and discharge control is not higher than the temperature represented by the target heat generation condition, it is determined that the heat generation state of the battery during the second stage of charge and discharge control meets the target heat generation condition.

[0084] Step S122: when the target thermal condition includes a target stress condition and the thermal state includes a stress state, the stress state of the battery during the second stage of charge and discharge control satisfies the target stress condition;

[0085] In some embodiments, when the expansion force of the battery during the second stage of charge and discharge control is not greater than the expansion force represented by the target stress condition, it is determined that the stress state of the battery during the second stage of charge and discharge control meets the target stress condition.

[0086] In some embodiments, when the internal pressure of the battery during the second stage of charge and discharge control is not greater than the internal pressure represented by the target stress condition, it is determined that the stress state of the battery during the second stage of charge and discharge control meets the target stress condition.

[0087] Step S123: When the target thermodynamic condition includes a target volume condition and the thermodynamic state includes a volume state, the volume state of the battery during the second stage of charge and discharge control satisfies the target volume condition.

[0088] In some embodiments, when the volume of the battery during the second stage of charge and discharge control is not greater than the volume represented by the target volume condition, it is determined that the volume state of the battery during the second stage of charge and discharge control meets the target volume condition.

[0089] In the disclosed embodiment, when the target thermal condition includes a target heat generation condition and the thermal state includes a heat generation condition, the heat generation condition of the battery during the second stage of charge and discharge control satisfies the target heat generation condition; when the target thermal condition includes a target stress condition and the thermal state includes a stress state, the stress state of the battery during the second stage of charge and discharge control satisfies the target stress condition; when the target thermal condition includes a target volume condition and the thermal state includes a volume state, the volume state of the battery during the second stage of charge and discharge control satisfies the target volume condition. In this way, whether the heat generation condition, stress state, and volume state satisfy their respective corresponding target heat generation condition, target stress condition, and target volume condition is considered separately, thereby improving the accuracy of determining whether the thermal state satisfies the target thermal condition.

[0090] In some embodiments, the target thermal condition includes a target change condition of the thermal state; the above step S113 may include the following step S131:

[0091] Step S131 : In response to the degree of change in the thermal state of the battery during the second stage of charge and discharge control satisfying a target change condition, determining a first candidate lower limit as the target discharge lower limit.

[0092] Here, the target change condition is a condition that the degree of change in the thermal state of the battery satisfies when the battery operates safely during the second stage of charge and discharge control.

[0093] In some embodiments, the degree of change in the thermal state may include, but is not limited to, at least one of an increment, an increase rate, etc. of the thermal state.

[0094] In the disclosed embodiment, if the degree of change in the battery's thermal state during the second stage of charge and discharge control meets the target change condition, the first candidate lower limit is determined as the target discharge lower limit. Because the battery's thermal state is a cumulative process, the degree of change in the thermal state can be used to determine whether the condition is met, accurately determining the extent of the thermal state change.

[0095] In some embodiments, the above step S131 may include the following steps S141 to S143:

[0096] Step S141: when the target change condition includes a target heat generation change condition and the degree of change in the thermal state includes a heat generation change degree, the heat generation change degree of the battery during the second stage of charge and discharge control satisfies the target heat generation change condition;

[0097] In some embodiments, when the heat generation variation degree includes a heat generation increase / increase rate, the heat generation increase / increase rate of the battery during the second stage of charge and discharge control meets the target heat generation variation condition.

[0098] In some embodiments, when the degree of heat generation variation includes a heat generation variation rate, the heat generation variation rate of the battery during the second stage of charge and discharge control satisfies a target heat generation variation condition.

[0099] Step S142: when the target change condition includes a target stress change condition and the degree of change in the thermal state includes a stress change degree, the stress change degree of the battery during the second stage of charge and discharge control satisfies the target stress change condition;

[0100] In some embodiments, when the stress change degree includes a stress increase / increase rate, the stress increase / increase rate of the battery during the second stage of charge and discharge control meets the target stress change condition.

[0101] In some embodiments, when the stress change degree includes a stress change rate, the stress change rate of the battery during the charge and discharge control process of the second stage meets the target stress change condition.

[0102] Step S143: When the target change condition includes a target volume change condition and the degree of change in the thermal state includes a volume change degree, the volume change degree of the battery during the second stage of charge and discharge control satisfies the target volume change condition.

[0103] In some embodiments, when the degree of volume change includes a volume increase / increase rate, the volume increase / increase rate of the battery during the second stage of charge and discharge control meets the target volume change condition.

[0104] In some embodiments, when the degree of volume change includes a volume change rate, the volume change rate of the battery during the second stage of charge and discharge control satisfies a target volume change condition.

[0105] In the embodiment of the present disclosure, when the target change condition includes a target heat generation change condition and the degree of change in the thermodynamic state includes the degree of heat generation change, the degree of heat generation change of the battery during the second stage of charge and discharge control satisfies the target heat generation change condition; when the target change condition includes a target stress change condition and the degree of change in the thermodynamic state includes the degree of stress change, the degree of stress change of the battery during the second stage of charge and discharge control satisfies the target stress change condition; when the target change condition includes a target volume change condition and the degree of change in the thermodynamic state includes the degree of volume change, the degree of volume change of the battery during the second stage of charge and discharge control satisfies the target volume change condition. In this way, whether the degree of heat generation change, the degree of stress change, and / or the degree of volume change satisfy their respective corresponding target heat generation change conditions, target stress change conditions, and target volume change conditions is considered respectively, thereby improving the accuracy of determining whether the degree of change in the thermodynamic state satisfies the target change conditions.

[0106] In some embodiments, the above method may further include the following steps S181 to S183:

[0107] Step S181: determining a first rate of change of the thermal state of the battery during the third stage of charge and discharge control; the third stage is a stage of performing charge and discharge control on the battery before the health state value decays to the first state threshold;

[0108] Here, the third stage is a stage of controlling the charge and discharge of the battery before the health state value decays to the first state threshold, that is, a process of controlling the charge and discharge of the battery before adjusting the lower discharge limit.

[0109] Exemplarily, based on the thermal state of the battery during the charge and discharge control process before the health state value decays to the first state threshold, a straight line of the thermal state is fitted, and the first slope of the straight line is determined. The first slope is used as the first change rate of the thermal state of the battery during the charge and discharge control process in the third stage.

[0110] Exemplarily, the ratio of the thermal state at the first moment during the charge and discharge control of the battery before the health state value decays to the first state threshold and the thermal state at the previous moment is determined as a first ratio, and the first ratio is used as the first change rate of the thermal state of the battery during the charge and discharge control process in the third stage.

[0111] Step S182: determining a second rate of change of the thermal state of the battery during the second stage of charge and discharge control;

[0112] Exemplarily, based on the thermal state of the battery during charge and discharge control as the health state value decays from a first state threshold to a current health state value, a real-time change curve of the thermal state is fitted, and based on the real-time change curve, a real-time second slope is determined, and the real-time second slope is used as the real-time second change rate of the thermal state of the battery during the second stage of charge and discharge control.

[0113] Exemplarily, when the health state value decays from the first state threshold to the current health state value, the ratio of the thermal state at the current moment and the moment before the current moment is determined in real time during the charge and discharge control of the battery, and the real-time second ratio is determined. The real-time second ratio is used as the real-time second change rate of the thermal state of the battery during the second stage of charge and discharge control.

[0114] Step S183: When the ratio of the second change rate to the first change rate is not greater than the first ratio threshold, determine whether the degree of change in the thermal state of the battery during the second stage of charge and discharge control meets the target change condition.

[0115] In some embodiments, by real-time monitoring of the ratio of the second change rate to the first change rate, it is measured whether the thermal state of the battery during the charge and discharge control process meets the target change condition.

[0116] In the embodiment of the present disclosure, the third stage is a stage in which the battery is charged and discharged before the health state value decays to the first state threshold. When the ratio of the second rate of change of the thermal state of the battery during the charge and discharge control process of the second stage to the first rate of change of the thermal state during the charge and discharge control process of the third stage is not greater than the first ratio threshold, it is determined that the degree of change of the thermal state of the battery during the charge and discharge control process of the second stage meets the target change condition. In this way, the relationship between the degree of change of the thermal state of the battery during the charge and discharge control process of the second stage and the degree of change of the thermal state of the battery during the charge and discharge control process of the third stage can be determined based on the ratio of the second rate of change to the first rate of change, thereby determining whether the current degree of change of the thermal state has the risk of damaging the battery, that is, whether the current degree of change of the thermal state meets the target change condition.

[0117] In some embodiments, the above step S102 may include the following step S151:

[0118] Step S151 : in response to the thermal state of the battery in the first stage of charge and discharge control not satisfying the target thermal condition, determining a reference discharge lower limit as the target discharge lower limit, the reference discharge lower limit being higher than the first candidate lower limit.

[0119] In some embodiments, when it is detected that the thermal state of the battery during the first stage of charge and discharge control does not meet the target thermal condition, a reference discharge lower limit higher than the first candidate lower limit may be used as the target discharge lower limit.

[0120] In some embodiments, when it is detected that the thermal state of the battery during the first stage of charge and discharge control does not meet the target thermal conditions, it indicates that the battery is sensitive to gas and heat production. Therefore, the reference discharge lower limit can be the initial discharge lower limit when the discharge lower limit is not adjusted, making the battery safer during operation.

[0121] In the disclosed embodiment, in response to the battery's thermal state not meeting the target thermal condition during the first stage of charge and discharge control, a reference lower discharge limit is determined as the target lower discharge limit, and the reference lower discharge limit is higher than the first candidate lower limit. Thus, when the thermal state does not meet the target thermal condition, the reference lower discharge limit, which is higher than the first candidate lower limit, is determined as the target lower discharge limit, thereby reducing damage to the battery caused by the thermal condition.

[0122] In some embodiments, the above step S111 may include the following steps S161 and S162:

[0123] Step S161: determining the adjustment step size of the discharge lower limit;

[0124] Here, the adjustment step size is the value by which the lower discharge limit is lowered every time the battery health status value decays by 1%.

[0125] In some embodiments, the lower discharge limit can be adjusted proportionally. The lower discharge limit can be evenly adjusted according to the decay interval of the health status value (i.e., the SOH interval of the battery life cycle) and the interval in which the lower discharge limit can be lowered. That is, the decay interval is divided by the interval in which the lower discharge limit can be lowered to obtain the adjustment step size. This method is simpler and easier to implement.

[0126] In some embodiments, when the health status value is large, the battery performance is better. If the discharge lower limit is lowered too much at this time, it may cause the battery to decay faster. Therefore, a smaller adjustment step size can be set in the early stage of health status value decay, and a larger step size can be set in the later stage of health status value decay to slow down the battery aging.

[0127] Step S162: Based on the adjustment step size, the discharge lower limit is adjusted down to the first candidate lower limit.

[0128] In some implementations, a first candidate lower limit is determined based on the current discharge lower limit and the adjustment step size, and the discharge lower limit is adjusted down to the first candidate lower limit.

[0129] In the embodiment of the present disclosure, an adjustment step size of the discharge lower limit is determined; based on the adjustment step size, the discharge lower limit is adjusted down to the first candidate lower limit. In this way, the discharge lower limit can be adjusted down to a suitable first candidate lower limit according to a suitable adjustment step size.

[0130] In some embodiments, the above step S161 may include the following step S171:

[0131] Step S171: Based on the current health state value of the battery, determine the adjustment step size of the lower discharge limit; wherein the adjustment step size is inversely proportional to the current health state value.

[0132] In some embodiments, an adjustment step size of the lower discharge limit corresponding to the health state value is determined, and a smaller adjustment step size is set for a larger health state value, and a larger adjustment step size is set for a smaller health state value.

[0133] In some embodiments, a decay interval for the health state value and a lowering interval for the discharge lower limit are determined; the decay interval is divided into multiple sub-decay intervals, and the lowering interval includes multiple sub-lowering intervals; the sub-lowering intervals corresponding to each of the multiple sub-decay intervals are determined; and based on the multiple sub-decay intervals and the sub-lowering intervals corresponding to each of the multiple sub-decay intervals, an adjustment step size for the discharge lower limit corresponding to each of the multiple sub-decay intervals is determined. Here, the adjustment step size for the discharge lower limit corresponding to the health state values in the same sub-decay interval is the same, and each sub-decay interval may include one or more health state values; and the larger the health state value in the multiple sub-decay intervals, the smaller the corresponding adjustment step size.

[0134] In the disclosed embodiment, the adjustment step size of the lower discharge limit is determined based on the current state of health value of the battery; wherein the adjustment step size is inversely proportional to the current state of health value. Thus, when the state of health value is large, greater consideration is given to minimizing damage to the battery. Therefore, a smaller adjustment step size can be set to reduce damage to the battery caused by excessive reduction of the lower discharge limit, thereby slowing down battery aging. When the state of health value is small, greater consideration is given to increasing the remaining capacity of the battery. In this way, as the battery's state of health continues to decline, the need to increase the remaining capacity of the battery and the need to reduce battery damage can be balanced, thereby improving the overall performance of the battery during use.

[0135] The present disclosure provides a battery management system. Figure 2 A schematic diagram of the structure of a battery management system provided in an embodiment of the present disclosure is shown in FIG. Figure 2 As shown, the battery management system 200 includes:

[0136] An acquisition module 201 is used to obtain target thermal conditions of the battery during the charging and discharging process;

[0137] an adjustment module 202 for adjusting, in response to the battery's current state of health value decaying below a first state threshold, a lower discharge limit of the battery in a charge / discharge interval based on a target thermal condition and a thermal state of the battery during a charge / discharge process, to obtain a target lower discharge limit;

[0138] The control module 203 is configured to perform a first-stage charge and discharge control on the battery based on the target lower discharge limit.

[0139] In the disclosed embodiment, the target thermal condition of the battery during the charge and discharge process is first obtained; secondly, when the current health state value of the battery decays to below the first state threshold, the lower discharge limit of the battery in the charge and discharge interval is adjusted according to the target thermal condition and the thermal state of the battery during the charge and discharge process to obtain the target discharge lower limit; finally, the battery is subjected to the first stage of charge and discharge control according to the target discharge lower limit. In this way, when it is detected that the current health state value decays to below the first state threshold, the thermal state of the battery during the charge and discharge process and the target thermal condition are comprehensively considered, and the lower discharge limit of the battery in the charge and discharge interval is adjusted, so that after the charge and discharge interval of the battery decays, the available remaining capacity of the battery is increased while reducing damage to the battery and slowing down the aging rate of the battery.

[0140] In some embodiments, the adjustment module includes: a downward adjustment unit for lowering the discharge lower limit to a first candidate lower limit; a control unit for performing a second-stage charge and discharge control of the battery based on the first candidate lower limit, and monitoring the thermal state of the battery during the second-stage charge and discharge control process; and a first determination unit for determining the first candidate lower limit as the target discharge lower limit in response to the thermal state of the battery during the second-stage charge and discharge control process meeting the target thermal condition.

[0141] In some embodiments, the first determination unit includes at least one of the following: when the target thermal condition includes a target heat generation condition and the thermal state includes a heat generation state, the heat generation state of the battery during the second stage of charge and discharge control meets the target heat generation condition; when the target thermal condition includes a target stress condition and the thermal state includes a stress state, the stress state of the battery during the second stage of charge and discharge control meets the target stress condition; when the target thermal condition includes a target volume condition and the thermal state includes a volume state, the volume state of the battery during the second stage of charge and discharge control meets the target volume condition.

[0142] In some embodiments, the first determination unit further includes: a first determination subunit, configured to determine the first candidate lower limit as the target discharge lower limit in response to the degree of change in the thermal state of the battery during the second stage of charge and discharge control meeting the target change condition.

[0143] In some embodiments, the first determination subunit includes at least one of the following: when the target change condition includes a target heat generation change condition and the degree of change of the thermal state includes the degree of heat generation change, the degree of heat generation change of the battery during the second stage of charge and discharge control meets the target heat generation change condition; when the target change condition includes a target stress change condition and the degree of change of the thermal state includes the degree of stress change, the degree of stress change of the battery during the second stage of charge and discharge control meets the target stress change condition; when the target change condition includes a target volume change condition and the degree of change of the thermal state includes the degree of volume change, the degree of volume change of the battery during the second stage of charge and discharge control meets the target volume change condition.

[0144] In some embodiments, the battery management system further comprises:

[0145] a first determination module, configured to determine a first rate of change of the thermal state of the battery during a third stage of charge and discharge control; the third stage being a stage of performing charge and discharge control on the battery before the health state value decays to a first state threshold;

[0146] a second determining module, configured to determine a second rate of change of the thermal state of the battery during the charge and discharge control process of the second stage;

[0147] The third determination module is configured to determine whether a degree of change in the thermal state of the battery during the second stage of charge and discharge control meets a target change condition when a ratio of the second change rate to the first change rate is not greater than a first ratio threshold.

[0148] In some embodiments, the adjustment module further includes: a second determination unit for determining the reference discharge lower limit as the target discharge lower limit in response to the thermal state of the battery during the first stage of charge and discharge control not meeting the target thermal condition, and the reference discharge lower limit is higher than the first candidate lower limit.

[0149] In some embodiments, the lowering unit includes: a second determining subunit, configured to determine an adjustment step size of the discharge lower limit; and a lowering subunit, configured to lower the discharge lower limit to the first candidate lower limit based on the adjustment step size.

[0150] In some embodiments, the second determining subunit is further configured to: determine an adjustment step size of the lower discharge limit based on a current health state value of the battery; wherein the adjustment step size is inversely proportional to the current health state value.

[0151] The present disclosure provides a battery system. Figure 3 A schematic diagram of the structure of a battery system provided in an embodiment of the present disclosure is shown in FIG. Figure 3 As shown, the battery system 300 includes a battery 301 and the above-mentioned battery management system 200 .

[0152] The following describes the application of the embodiments of the present disclosure in actual scenarios.

[0153] The voltage open range (corresponding to the charge and discharge range in the aforementioned embodiment) generally used by lithium iron phosphate batteries is not the maximum voltage range of the entire battery. In battery design, considering that the low voltage range has a greater risk of gas production and heat generation, the open range generally avoids the low voltage range, directly limiting the use of the low voltage range. This makes the capacity of the lithium iron phosphate battery not fully utilized, resulting in redundancy and waste. In actual battery use, the impact of different aging paths on gas production and direct current resistance (DCR) is more complex. Not all low voltage ranges under all aging paths will have safety issues such as gas production and heat generation. By designing a suitable algorithm in the battery management system (BMS) to monitor the gas production and heat generation of the battery, the lower limit of the cycle range can be appropriately released when conditions are right to increase the previously redundant capacity of the low voltage part and improve the battery's capacity decay rate.

[0154] For example, in the case of gas production by electrochemical reaction and heat generation by DCR, the lower discharge limit is considered to be set at 2.6V. However, in some scenarios, the discharge can continue to 2V. The difference in discharge capacity from 2.6V to 2V is the incremental capacity benefit generated by the voltage range opening strategy.

[0155] Design a cycle process with the same upper limit and different lower limits, such as 0%-100%, 10%-100%, and 20%-100% cycles. Keep other conditions the same and test the same battery cell for aging experiments. Convert the number of cycles to the equivalent full cycle number. Figure 4 As shown in the figure, the aging capacity retention rate of a certain battery at the discharge lower limit is 0%, 10%, 20% and 30% respectively. It can be seen that as the charging lower limit decreases, the aging rate of the equivalent full-range cycle number decreases, and the battery capacity retention rate is higher after the same equivalent full cycle number (that is, the battery attenuation slows down).

[0156] Due to some aging conditions, it is not suitable to open the low voltage range of power, so it is necessary to monitor battery gas production, DCR and other parameters in the BMS to determine whether to open the low voltage capacity according to the battery condition. The specific principle is as follows:

[0157] When the BMS estimates the battery's SOH is below 85%, it can enable the low-voltage range. The amount enabled is proportional to the SOH. For example, for every 2% decrease in SOH, the low-voltage range is reduced by 0.1V until it reaches the 2.0V limit and no further reduction is achieved. The BMS also monitors the DCR and internal battery pressure, measuring the risk of gassing by the slope of pressure increase before and after enabling the low-voltage range. If the BMS determines there is a risk of abnormal gassing, it will disable the low-voltage range.

[0158] A test was conducted on a certain type of lithium iron phosphate battery. The open voltage range was designed to be 2.5~3.65V. Two cells with good consistency were selected for testing. The ambient temperature was set to 45 degrees Celsius, and the capacity data was tested every 500 cycles. One of the cells dynamically adjusted the lower discharge limit. After the SOH decayed to 90%, a special BMS control system was used to dynamically adjust the lower discharge limit. For every 1% decay, the battery's lower discharge limit was reduced by 0.02V until the lower limit reached 2.0V. At the same time, the battery pressure and expansion force were monitored. If there was no abnormality, the lower limit would continue to be lowered. Otherwise, the lower limit would be restored to 2.5V. No abnormalities occurred in this test. After the SOH of the test group with dynamic adjustment of the lower discharge limit decayed to around 85%, its cycle lower limit voltage was 2.2V. The other battery was tested as a control group without adjusting the lower discharge limit.

[0159] By comparing the test results of the dynamic adjustment discharge lower limit with the test results of the control group, such as Figure 5 As shown in the figure, after adjusting the dynamic voltage around 4000 cycles (90% SOH), the capacity increased slightly (increasing the previously redundant capacity in the low-voltage section). The battery's subsequent degradation trend also slowed, and the aging slope was significantly reduced (improving the battery's capacity decay rate). When the SOH decayed to 85%, the battery gas production and expansion force monitoring did not alarm, and no abnormal threshold value exceeded the threshold. This shows that dynamically adjusting the lower discharge limit can effectively increase the battery's available remaining capacity and extend its service life.

[0160] In the embodiment of the present disclosure, by detecting the heat generation or heat generation condition of the battery and dynamically adjusting the lower discharge limit, the originally redundant capacity of the low-voltage part can be increased, the available remaining capacity of the battery can be effectively improved, and the battery service life can be extended.

[0161] It should be noted that in the embodiments of the present disclosure, if the above-mentioned method is implemented in the form of a software function module and sold or used as an independent product, it can also be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the embodiments of the present disclosure, or the part that contributes to the relevant technology, can be embodied in the form of a software product. The software product is stored in a storage medium and includes a number of instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the methods of each embodiment of the present disclosure. The aforementioned storage medium includes various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a magnetic disk, or an optical disk. In this way, the embodiments of the present disclosure are not limited to any specific hardware, software, or firmware, or any combination of hardware, software, and firmware.

[0162] An embodiment of the present disclosure provides a computer device including a memory and a processor, wherein the memory stores a computer program that can be run on the processor, and when the processor executes the program, some or all of the steps in the above method are implemented.

[0163] The present disclosure provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements some or all of the steps in the above method. The computer-readable storage medium may be transient or non-transient.

[0164] An embodiment of the present disclosure provides a computer program, including computer-readable codes. When the computer-readable codes are executed in a computer device, a processor in the computer device executes some or all of the steps for implementing the above method.

[0165] The present disclosure provides a computer program product comprising a non-transitory computer-readable storage medium storing a computer program. When the computer program is read and executed by a computer, some or all of the steps of the above-described method are implemented. The computer program product may be implemented in hardware, software, or a combination thereof. In some embodiments, the computer program product is embodied as a computer storage medium. In other embodiments, the computer program product is embodied as a software product, such as a software development kit (SDK).

[0166] It should be noted that the descriptions of the various embodiments above tend to emphasize the differences between the embodiments, and reference can be made to the similarities or similarities between them. The descriptions of the above embodiments of the device, storage medium, computer program, and computer program product are similar to the descriptions of the above-mentioned method embodiments and have similar beneficial effects as the method embodiments. For technical details not disclosed in the embodiments of the device, storage medium, computer program, and computer program product disclosed herein, please refer to the description of the method embodiments disclosed herein for understanding.

[0167] It should be noted that Figure 6 A schematic diagram of a hardware entity of a computer device in an embodiment of the present disclosure is shown in FIG. Figure 6 As shown, the hardware entity of the computer device 600 includes: a processor 601, a communication interface 602 and a memory 603, wherein:

[0168] Processor 601 generally controls the overall operation of computer device 600 .

[0169] The communication interface 602 enables the computer device to communicate with other terminals or servers through a network.

[0170] Memory 603 is configured to store instructions and applications executable by processor 601. It can also cache data to be processed or processed by processor 601 and various modules in computer device 600 (e.g., image data, audio data, voice communication data, and video communication data). This can be implemented using flash memory (FLASH) or random access memory (RAM). Data can be transmitted between processor 601, communication interface 602, and memory 603 via bus 604.

[0171] It should be understood that “one embodiment” or “an embodiment” mentioned throughout the specification means that specific features, structures or characteristics related to the embodiment are included in at least one embodiment of the present disclosure. Therefore, “in one embodiment” or “in an embodiment” appearing throughout the specification does not necessarily refer to the same embodiment. In addition, these specific features, structures or characteristics can be combined in one or more embodiments in any suitable manner. It should be understood that in the various embodiments of the present disclosure, the size of the serial numbers of the above-mentioned steps / processes does not mean the order of execution, and the execution order of each step / process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present disclosure. The serial numbers of the embodiments of the present disclosure are for description only and do not represent the advantages and disadvantages of the embodiments.

[0172] It should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0173] In the several embodiments provided in the present disclosure, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of units is merely a logical function division. In actual implementation, there may be other division methods, such as: multiple units or components can be combined, or can be integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the components shown or discussed can be through some interfaces, and the indirect coupling or communication connection of devices or units can be electrical, mechanical or other forms.

[0174] The units described above as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; they may be located in one place or distributed across 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. In addition, the functional units in the various embodiments of the present disclosure may all be integrated into one processing unit, or each unit may be separately used as a unit, or two or more units may be integrated into one unit; the above-mentioned integrated units may be implemented in the form of hardware or in the form of hardware plus software functional units.

[0175] Those skilled in the art will understand that all or part of the steps of the above-mentioned method embodiment can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above-mentioned method embodiment; and the aforementioned storage medium includes: mobile storage devices, read-only memories (ROM), magnetic disks or optical disks, and other media that can store program codes.

[0176] Alternatively, if the integrated units described above are implemented as software functional modules and sold or used as independent products, they can also be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present disclosure, or the portion that contributes to the relevant technology, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes a number of instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the methods of the various embodiments of the present disclosure. The aforementioned storage medium includes various media that can store program code, such as mobile storage devices, ROMs, magnetic disks, or optical disks.

[0177] The above are only implementation methods of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any changes or replacements that can be easily conceived by any technician familiar with this technical field within the technical scope disclosed in this disclosure should be covered by the protection scope of the present disclosure.

Claims

1. A battery control method, characterized in that: The method comprises: Obtaining target thermal conditions of the battery during charging and discharging; In response to the current state of health value of the battery decaying below a first state threshold, adjusting a lower discharge limit in a charge and discharge interval of the battery based on the target thermal condition and a thermal state of the battery during charge and discharge to obtain a target lower discharge limit; Based on the target lower discharge limit, performing a first-stage charge and discharge control on the battery; The step of adjusting the lower discharge limit in the charge and discharge interval of the battery based on the target thermal condition and the thermal state of the battery during the charge and discharge process to obtain the target lower discharge limit includes: adjusting the discharge lower limit to a first candidate lower limit; performing a second-stage charge and discharge control on the battery based on the first candidate lower limit, and monitoring a thermal state of the battery during the second-stage charge and discharge control process; In response to the thermal state of the battery during the second stage of charge and discharge control satisfying the target thermal condition, the first candidate lower limit is determined as the target discharge lower limit; the target thermal condition includes a ratio of the second change rate to the first change rate being no greater than a first ratio threshold, the first change rate being the rate of change of the thermal state of the battery during the third stage of charge and discharge control, the third stage being the stage of charge and discharge control of the battery before the health state value decays to the first state threshold, and the second change rate being the rate of change of the thermal state of the battery during the second stage of charge and discharge control.

2. The method according to claim 1, wherein The thermal state of the battery during the second stage of charge and discharge control satisfies the target thermal condition, including at least one of the following: When the target thermal condition includes a target heat generation condition and the thermal state includes a heat generation state, the heat generation state of the battery during the charge and discharge control process of the second stage satisfies the target heat generation condition; When the target thermal condition includes a target stress condition and the thermal state includes a stress state, the stress state of the battery during the charge and discharge control process of the second stage satisfies the target stress condition; When the target thermodynamic condition includes a target volume condition and the thermodynamic state includes a volume state, the volume state of the battery during the second stage of charge and discharge control satisfies the target volume condition.

3. The method according to claim 1, wherein The target thermal conditions include target change conditions of thermal state; In response to the thermal state of the battery in the second stage of charge and discharge control satisfying the target thermal condition, determining the first candidate lower limit as the target discharge lower limit includes: In response to a degree of change in the thermal state of the battery during the second stage of charge and discharge control satisfying the target change condition, the first candidate lower limit is determined as the target discharge lower limit.

4. The method according to claim 3, wherein The degree of change in the thermal state of the battery during the charge and discharge control process of the second stage satisfies the target change condition, including at least one of the following: When the target change condition includes a target heat generation change condition and the degree of change in the thermal state includes a degree of heat generation change, the degree of heat generation change of the battery during the charge and discharge control process of the second stage satisfies the target heat generation change condition; When the target change condition includes a target stress change condition and the degree of change in the thermal state includes a stress change degree, the stress change degree of the battery during the charge and discharge control process of the second stage satisfies the target stress change condition; When the target change condition includes a target volume change condition and the degree of change in the thermal state includes a degree of volume change, the degree of volume change of the battery during the second stage of charge and discharge control satisfies the target volume change condition.

5. The method according to claim 3, characterized in that The method further comprises: determining a first rate of change of the thermal state of the battery during a third stage of charge and discharge control; the third stage being a stage of performing charge and discharge control on the battery before the health state value decays to the first state threshold; determining a second rate of change of the thermal state of the battery during the second stage of charge and discharge control; When the ratio of the second change rate to the first change rate is not greater than a first ratio threshold, it is determined that the degree of change in the thermal state of the battery during the second stage of charge and discharge control meets the target change condition.

6. The method according to any one of claims 1 to 5, characterized in that The step of adjusting the lower discharge limit in the charge and discharge interval of the battery based on the target thermal condition and the thermal state of the battery during the charge and discharge process to obtain a target lower discharge limit further includes: In response to the thermal state of the battery during the first stage of charge and discharge control not satisfying the target thermal condition, a reference discharge lower limit is determined as the target discharge lower limit, the reference discharge lower limit being higher than the first candidate lower limit.

7. The method according to any one of claims 1 to 5, characterized in that The step of lowering the discharge lower limit to a first candidate lower limit includes: determining an adjustment step size of the discharge lower limit; Based on the adjustment step size, the discharge lower limit is adjusted down to the first candidate lower limit.

8. The method according to claim 7, characterized in that The step of determining the adjustment step of the lower discharge limit includes: An adjustment step size of the lower discharge limit is determined based on the current health state value of the battery; wherein the adjustment step size is in inverse proportion to the current health state value.

9. A battery management system, characterized in that: The battery management system includes: an acquisition module, configured to acquire target thermal conditions of the battery during the charge and discharge process; an adjustment module, configured to, in response to the current health state value of the battery decaying below a first state threshold, adjust a lower discharge limit in a charge and discharge interval of the battery based on the target thermal condition and the thermal state of the battery during the charge and discharge process to obtain a target lower discharge limit; a control module, configured to perform a first-stage charge and discharge control on the battery based on the target lower discharge limit; The adjustment module is further configured to lower the discharge lower limit to a first candidate lower limit; perform a second-stage charge and discharge control on the battery based on the first candidate lower limit, and monitor the thermal state of the battery during the second-stage charge and discharge control process; in response to the thermal state of the battery during the second-stage charge and discharge control process satisfying the target thermal condition, determine the first candidate lower limit as the target discharge lower limit; the target thermal condition includes a ratio of the second change rate to the first change rate being no greater than a first ratio threshold, the first change rate being the rate of change of the thermal state of the battery during the third stage of charge and discharge control, the third stage being a stage of charge and discharge control of the battery before the health state value decays to the first state threshold, and the second change rate being the rate of change of the thermal state of the battery during the second stage of charge and discharge control.

10. A battery system, characterized in that: The battery system comprises a battery and the battery management system according to claim 9.

11. A computer device comprising a memory and a processor, wherein the memory stores a computer program that can be run on the processor, characterized in that: When the processor executes the program, the steps of the method according to any one of claims 1 to 8 are implemented.

12. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 8 are implemented.

13. A computer program product comprising a computer program or instructions, characterized in that When the computer program or instruction is executed by a processor, the steps of the method according to any one of claims 1 to 8 are implemented.

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