An electrochemical device management method, system, battery module and electronic device

Abstract

Embodiments of the present application provide an electrochemical device management method and system, a battery module and an electronic device, comprising: performing a first charge-discharge cycle on the electrochemical device with a charging current; performing an intermittent charging operation on the electrochemical device, obtaining data related to the electrochemical device in the intermittent charging operation, determining a lithium precipitation SOC of the electrochemical device based on the data related to the electrochemical device; in response to the lithium precipitation SOC being greater than a second SOC threshold and less than or equal to a first SOC threshold, controlling the electrochemical device to perform a lithium precipitation reduction operation; and controlling the electrochemical device to perform a second charge-discharge cycle at a first temperature and a first charge-discharge rate. The embodiments of the present application can reduce the lithium precipitation generated by the electrochemical device and improve the safety of the electrochemical device during use.

Description

Technical Field

[0001] This application relates to the field of electrochemical technology, and in particular to an electrochemical device management method, system, battery module, and electronic device. Background Technology

[0002] Lithium-ion batteries have many advantages, such as high energy density, long cycle life, high nominal voltage, low self-discharge rate, small size, and light weight, and are widely used in the consumer electronics field.

[0003] As lithium-ion batteries are used, their lithium plating window gradually narrows. For example, lithium-ion batteries do not plating when charged at the rated current during the initial cycling phase, but as cycling progresses, continuing to charge at the rated current will cause lithium plating. Therefore, it is necessary to accurately detect the risk of lithium plating in lithium-ion batteries and to promptly reduce existing lithium plating. Summary of the Invention

[0004] The purpose of this application is to provide a method, system, battery module, and electronic device for managing electrochemical devices, so as to accurately detect the risk of lithium plating in electrochemical devices and reduce the lithium plating that has already occurred, thereby improving the safety of electrochemical devices. The specific technical solution is as follows:

[0005] A first aspect of this application provides an electrochemical device management method, comprising performing a first charge-discharge cycle on the electrochemical device with a charging current; performing an intermittent charging operation on the electrochemical device, acquiring data related to the electrochemical device during the intermittent charging operation, and determining the lithium plating state occupancy (SOC) of the electrochemical device based on the data related to the electrochemical device; controlling the electrochemical device to perform a lithium plating reduction operation in response to the lithium plating SOC being greater than a second SOC threshold and less than or equal to a first SOC threshold; and controlling the electrochemical device to perform a second charge-discharge cycle at a first charge-discharge rate at a first temperature, wherein the second SOC threshold is less than the first SOC threshold.

[0006] The beneficial effects of the embodiments of this application are as follows: By responding to the lithium plating SOC being less than or equal to a first SOC threshold, the embodiments of this application control the electrochemical device to perform a lithium plating reduction operation, that is, control the electrochemical device to perform a second charge-discharge cycle at a first charge-discharge rate at a first temperature, which can reduce the lithium plating already generated by the electrochemical device and improve the safety of the electrochemical device during use.

[0007] In one embodiment of this application, the method further includes controlling the electrochemical device to stop working and generating a prompt message in response to the lithium plating SOC being less than or equal to the second SOC threshold, so that the user can be informed in a timely manner that the electrochemical device is no longer usable due to performance degradation, thereby improving the user experience.

[0008] In one embodiment of this application, the method further includes reducing at least one of the charging voltage or charging current of the electrochemical device in response to the lithium plating SOC being greater than a third SOC threshold and less than or equal to the second SOC threshold, thereby reducing the risk of lithium plating occurring in the electrochemical device due to continued operation at the current voltage and / or current, and improving the safety of the electrochemical device in use.

[0009] In one embodiment of this application, reducing at least one of the charging voltage or charging current of the electrochemical device includes: i-1 reducing the current charging voltage of the electrochemical device by a first reduction to a first charging voltage, wherein the first charging voltage is the updated current charging voltage; and / or, i-2 reducing the current charging current of the electrochemical device by a second reduction to a first charging current, wherein the first charging current is the updated current charging current.

[0010] In one embodiment of this application, the method further includes: ii-1 reducing the second SOC threshold and the third SOC threshold by a third reduction rate to obtain an updated second SOC threshold and an updated third SOC threshold; iii-1 performing a third charge-discharge cycle on the electrochemical device with a charging current; iv-1 in response to the completion of the third charge-discharge cycle, performing an intermittent charging operation on the electrochemical device again, acquiring data related to the electrochemical device during the intermittent charging operation, determining the lithium plating SOC of the electrochemical device based on the data related to the electrochemical device, and determining the magnitude relationship between the lithium plating SOC and the updated second SOC threshold and the updated third SOC threshold; v-1 when the lithium plating SOC is greater than the updated third SOC threshold and less than the updated second SOC threshold, repeating steps i-1 to iii-1 until the difference between the current charging voltage and the initial charging voltage of the electrochemical device is greater than the voltage difference threshold, generating a prompt message, thereby extending the service life of the electrochemical device and improving the user experience.

[0011] In one embodiment of this application, the method further includes: ii-2 In response to the electrochemical device completing a third charge-discharge cycle, performing an intermittent charging operation on the electrochemical device again, acquiring data related to the electrochemical device during the intermittent charging operation, determining the lithium plating SOC of the electrochemical device based on the data related to the electrochemical device, and determining the magnitude relationship between the lithium plating SOC and the second SOC threshold and the third SOC threshold; iii-2 When the lithium plating SOC is greater than the third SOC threshold and less than the second SOC threshold, repeating steps i-2 to ii-2 until the difference between the current charging current and the initial charging current of the electrochemical device is greater than the current difference threshold, generating a prompt message, thereby extending the service life of the electrochemical device and improving the user experience.

[0012] In one embodiment of this application, a heating element is provided inside the electrochemical device and / or on the outer surface of the electrochemical device, thereby effectively heating the electrochemical device to reduce the generation of reversible lithium plating.

[0013] In one embodiment of this application, the heating element is made of at least one of nickel, nickel-aluminum alloy, copper, polyimide, silicone, or a positive temperature coefficient material; the impedance of the heating element is in the range of 0.01Ω to 50Ω, and it has good heating performance, thereby effectively reducing reversible lithium plating in the electrochemical device.

[0014] In one embodiment of this application, the first temperature ranges from 30°C to 70°C, and the first charge / discharge rate ranges from 0.01C to 0.5C. This allows the lithium plating already formed in the electrochemical device to gradually dissolve and decrease, eliminating the need to perform lithium plating reduction operations at different charge / discharge rates on the electrochemical device. This simplifies the lithium plating reduction operation steps and makes it more suitable for practical applications.

[0015] In one embodiment of this application, the data related to the electrochemical device includes the state of charge (SOC) and internal resistance of the electrochemical device. The intermittent charging operation includes multiple charging periods and multiple interruptions. The step of acquiring the data related to the electrochemical device during the intermittent charging operation and determining the lithium plating SOC of the electrochemical device based on the data includes: during the intermittent charging operation, for each of the multiple interruptions, acquiring the SOC and internal resistance of the electrochemical device during the interruption period; obtaining a first curve based on the acquired multiple SOCs and the multiple internal resistances corresponding to the multiple SOCs, wherein the first curve is a mapping curve corresponding to the SOC and internal resistance of the electrochemical device; and determining the lithium plating SOC of the electrochemical device based on the first curve, so as to perform lithium plating reduction operations on the electrochemical device in a timely manner based on the relationship between the lithium plating SOC and the SOC threshold, thereby improving the safety of the electrochemical device.

[0016] In one embodiment of this application, the step of determining the lithium plating SOC of the electrochemical device based on the first curve includes at least one of method 1 or method 2, wherein: method 1 includes performing a first-order derivative on the first curve to obtain a second curve; and determining the SOC corresponding to the first point on the second curve where the slope is negative as the lithium plating SOC. Method 2 includes performing a first-order derivative on the first curve to obtain a second curve; performing a second-order derivative on the second curve to obtain a third curve; and determining the SOC corresponding to the first point on the third curve where the ordinate is less than zero as the lithium plating SOC.

[0017] In one embodiment of this application, the intermittent charging operation includes multiple charging cycles, each charging cycle including a charging period and an intermittent period, during which the SOC of the electrochemical device increases by a unit magnitude.

[0018] In one embodiment of this application, the electrochemical device includes at least one of a lithium iron phosphate system electrochemical device, a lithium nickel cobalt manganese oxide system electrochemical device, or a lithium cobalt oxide system electrochemical device. Specifically, the electrochemical device is a lithium iron phosphate system electrochemical device, the unit amplitude ranges from 0.5% to 10%, and the duration of the intermittent period ranges from 1 second to 15 seconds; the electrochemical device is a lithium nickel cobalt manganese oxide system electrochemical device, the unit amplitude ranges from 0.5% to 10%, and the duration of the intermittent period ranges from 1 second to 30 seconds; or the electrochemical device is a lithium cobalt oxide system electrochemical device, the unit amplitude ranges from 0.5% to 10%, and the duration of the intermittent period ranges from 1 second to 30 seconds. This embodiment of the application more specifically performs intermittent charging operations on electrochemical devices of different electrochemical systems, enabling more accurate determination of the lithium plating state of charge (SOC) of the electrochemical devices of different electrochemical systems.

[0019] In one embodiment of this application, the method satisfies any one of conditions a) to f): a) the electrochemical device is a lithium iron phosphate system electrochemical device, the electrochemical device is at an ambient temperature of -10°C to 10°C, the unit amplitude ranges from 0.5% to 10%, and the duration of the interruption period ranges from 5 seconds to 15 seconds; b) the electrochemical device is a lithium iron phosphate system electrochemical device, the electrochemical device is at an ambient temperature of 10°C to 45°C, the unit amplitude ranges from 0.5% to 10%, and the duration of the interruption period ranges from 1 second to 10 seconds; c) the electrochemical device is a lithium nickel cobalt manganese oxide system electrochemical device, the electrochemical device is at an ambient temperature of -10°C to 10°C, the unit amplitude ranges from 0.5% to 10%, and the... The duration of the intermittent period ranges from 10 to 30 seconds; d) the electrochemical device is a lithium nickel cobalt manganese oxide system electrochemical device, the electrochemical device is in an ambient temperature range of 10°C to 45°C, the unit amplitude ranges from 0.5% to 10%, and the duration of the intermittent period ranges from 1 to 10 seconds; e) the electrochemical device is a lithium cobalt oxide system electrochemical device, the electrochemical device is in an ambient temperature range of -10°C to 10°C, the unit amplitude ranges from 0.5% to 10%, and the duration of the intermittent period ranges from 15 to 30 seconds; f) the electrochemical device is a lithium cobalt oxide system electrochemical device, the electrochemical device is in an ambient temperature range of 10°C to 45°C, the unit amplitude ranges from 0.5% to 10%, and the duration of the intermittent period ranges from 1 to 10 seconds. The embodiments of this application more specifically perform intermittent charging operations on electrochemical devices in different temperature environments, and can more accurately obtain the lithium plating SOC of electrochemical devices of different systems.

[0020] A second aspect of this application provides a system including a processor and a machine-readable storage medium storing machine-executable instructions executable by the processor, wherein the processor, when executing the machine-executable instructions, implements the method described in the first aspect.

[0021] A third aspect of this application provides a battery module comprising the system described in the second aspect above.

[0022] A fourth aspect of this application provides an electronic device, wherein the electronic device includes the battery module described in the third aspect above.

[0023] This application provides an electrochemical device management method, system, battery module, and electronic device. After performing a first charge-discharge cycle on the electrochemical device with a charging current, the device is intermittently charged. During this intermittent charging, data related to the electrochemical device is acquired, and the lithium plating state of charge (SOC) is determined based on this data. This allows for accurate detection of lithium plating risk in the battery, improving the safety of the electrochemical device during use. Furthermore, in response to the lithium plating SOC being less than or equal to a first SOC threshold, the electrochemical device is controlled to perform a lithium plating reduction operation. Specifically, the electrochemical device is controlled to perform a second charge-discharge cycle at a first temperature and a first charge-discharge rate, reducing the lithium plating already generated in the electrochemical device and further improving its safety during use. Of course, implementing any product or method of this application does not necessarily require achieving all of the above advantages simultaneously. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of this application and the prior art, the accompanying drawings used in the embodiments and the prior art are briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application.

[0025] Figure 1 This is a flowchart illustrating an electrochemical device management method according to one embodiment of this application;

[0026] Figure 2 This is a schematic diagram of the heating element arrangement according to one embodiment of this application;

[0027] Figure 3 A schematic diagram illustrating the heating element arrangement in another embodiment of this application;

[0028] Figure 4 This is a schematic diagram of the first curve of one embodiment of this application;

[0029] Figure 5 This is a schematic diagram of the second curve according to one embodiment of this application;

[0030] Figure 6 This is a schematic diagram of the system structure according to one embodiment of this application;

[0031] Figure 7 This is a schematic diagram of the structure of a charging device according to one embodiment of this application;

[0032] Figure 8 This is a schematic diagram of the charging device according to another embodiment of this application. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided with reference to the accompanying drawings and embodiments. Obviously, the described embodiments are merely some embodiments of this application, and not all embodiments. All other technical solutions obtained by those skilled in the art based on the embodiments of this application fall within the scope of protection of this application.

[0034] It should be noted that, in the specific embodiments of this application, lithium-ion batteries are used as an example of electrochemical devices to explain this application, but the electrochemical devices of this application are not limited to lithium-ion batteries.

[0035] This application provides a method for managing an electrochemical device, such as... Figure 1 As shown, the method includes the following steps:

[0036] S101: Perform the first charge-discharge cycle on the electrochemical device using the charging current;

[0037] The implementing entity in this application embodiment can be a Battery Management System (BMS). The BMS can be integrated into the electrochemical device or operate independently of the electrochemical device while communicating with it. During the operation of the electrochemical device, the BMS can manage the device. For example, during operation, the charging / discharging device 401 in the BMS performs a charge-discharge cycle on the electrochemical device using a charging current. The charge-discharge cycle in this application embodiment can refer to a charging-discharging-charging cycle during the operation of the electrochemical device. In the first charge-discharge cycle, the aforementioned charging current can be used to charge the electrochemical device during its charging phase. Furthermore, the discharge current in the charge-discharge cycle can be adapted to the electrical equipment; this application embodiment does not impose any limitations on this.

[0038] The embodiments of this application do not impose any particular limitation on the structure of the charging and discharging device. For example, it may include a charging and discharging circuit within the field of technology. This application does not limit this. Exemplarily, the above-mentioned charging and discharging circuit may be... Figure 8The charging and discharging circuit 504 shown is described. The charging current in this embodiment is not particularly limited, and can be any current between 0.1A and 3A, such as 0.1A, 0.2A, 0.3A, 0.5A, 0.7A, 1A, 1.5A, 2A, 2.5A or 3A.

[0039] S102: Perform intermittent charging operation on the electrochemical device, acquire data related to the electrochemical device during the intermittent charging operation, and determine the lithium plating SOC (State of Charge) of the electrochemical device based on the data related to the electrochemical device.

[0040] In this embodiment, intermittent charging operation can refer to the process of intermittently charging the electrochemical device. Lithium plating state of charge (SOC) can refer to the SOC related to the lithium plating state of the electrochemical device. For example, the SOC analysis device 402 in the battery management system can perform intermittent charging operation on the electrochemical device. This embodiment does not impose any particular limitation on the SOC analysis device, as long as it can implement intermittent charging operation. The SOC analysis device may include, for example, a microcontroller unit (MCU) in the battery management system (BMS).

[0041] In one example, after the charge / discharge device 401 performs a first charge / discharge cycle on the electrochemical device, the SOC analysis device 402, in response to the completion of the first charge / discharge cycle, performs an intermittent charging operation on the electrochemical device and performs lithium plating detection and analysis on the electrochemical device during the intermittent charging operation. Data related to the electrochemical device is acquired during the intermittent charging operation, and the lithium plating SOC of the electrochemical device is determined based on the data related to the electrochemical device. The above-described process is for illustrative purposes only.

[0042] Data related to an electrochemical device can refer to data that reflects the state of the electrochemical device, including but not limited to charging voltage, charging current, internal resistance, and state of charge (SOC). This application does not impose any particular limitation on the charging method in intermittent charging operations, as long as it achieves the purpose of this application. It can be constant voltage charging, constant current charging, constant current and constant voltage charging, or segmented constant current charging.

[0043] S103: In response to the lithium plating SOC being greater than the second SOC threshold and less than or equal to the first SOC threshold, the electrochemical device is controlled to perform a lithium plating reduction operation.

[0044] In this embodiment of the application, the process of controlling the electrochemical device to perform the lithium plating reduction operation is as follows: controlling the electrochemical device to perform a second charge-discharge cycle at a first charge-discharge rate at a first temperature.

[0045] The inventors of this application have discovered that when the lithium plating state of charge (SOC) is greater than a second SOC threshold and less than or equal to a first SOC threshold, the electrochemical device faces the risk of lithium plating. Based on this, embodiments of this application can perform a second charge-discharge cycle at a first temperature and a first charge-discharge rate, thereby reducing existing lithium plating in the electrochemical device, lowering the safety risks caused by lithium plating, and extending the lifespan of the electrochemical device. It is understood that when the capacity of the electrochemical device is constant, its charging rate is directly proportional to the charging current. Therefore, embodiments of this application can also control the electrochemical device to perform a second charge-discharge cycle at a first temperature and a first charge-discharge current, which is reasonable.

[0046] The first temperature in this application embodiment can be a temperature higher than room temperature, and the first charge / discharge rate can be a relatively small charge / discharge rate. In one embodiment, the first temperature ranges from 30°C to 70°C, and the first charge / discharge rate ranges from 0.01C to 0.5C. A first charge / discharge rate higher than 0.5C can easily cause lithium dendrites to dissolve too quickly, leading to dendrite breakage. Conversely, a rate lower than 0.01C results in a prolonged recovery time, and the dissolution effect no longer increases with decreasing rate. Therefore, performing multiple recovery cycles at a first charge / discharge rate of 0.01C to 0.5C can thoroughly and effectively reduce lithium dendrite formation. The inventors of this application have found that low-rate charge / discharge cycles at high temperatures are beneficial for reducing reversible lithium plating in electrochemical devices, but the temperature should not be too high, otherwise it can easily increase side reactions in the electrochemical device, leading to increased gas production. Based on this, the preferred first temperature range in this application embodiment is 35°C to 55°C. This application embodiment, by coordinating the control of the first temperature and the first charge / discharge rate within the aforementioned range, enables the lithium plating already formed in the electrochemical device to gradually dissolve and reduce. This eliminates the need for lithium plating reduction operations at different charge / discharge rates, such as first performing lithium plating reduction operations at a higher charge / discharge rate and then at a lower rate. This simplifies the lithium plating reduction process, mitigating the user experience degradation caused by frequent lithium plating reduction operations, and making it more suitable for practical applications, such as lithium plating reduction operations on electrical devices including electrochemical devices. For example, the above-mentioned application scenarios may include, but are not limited to, lithium plating reduction operations on electrochemical devices in electrical devices such as mobile phones, tablets, electric vehicles, and electric bicycles. In this application embodiment, the number of the second charge / discharge cycles can be 6 to 10 times, which can more thoroughly reduce the lithium plating formed in the electrochemical device.

[0047] This application embodiment determines the state of charge (SOC) of the electrochemical device based on intermittent charging operations, and then determines the timing of performing a lithium plating reduction operation based on the relationship between the determined SOC and a first SOC threshold and a second SOC threshold. Compared to methods that determine the timing of lithium plating reduction operations based on the real-time capacity of the electrochemical device, the method in this application embodiment, since the SOC is a state of charge related to the lithium plating state of the electrochemical device, can reflect the lithium plating tendency of the electrochemical device. Therefore, it can more accurately determine whether lithium plating has occurred in the electrochemical device, avoiding the problem that severe lithium plating may occur in actual use due to the inability to confirm the lithium plating situation, resulting in poor lithium plating reduction effects even after lithium plating reduction operations are performed. This is more conducive to improving the safety of the electrochemical device.

[0048] In one example, the SOC analysis device 402 performs intermittent charging of the electrochemical device. During the intermittent charging operation, it performs lithium plating detection and analysis on the electrochemical device. If the lithium plating SOC of the electrochemical device is greater than a second SOC threshold but less than or equal to a first SOC threshold, the management unit 403 controls the electrochemical device to perform a lithium plating reduction operation. It is understood that the second SOC threshold is less than the first SOC threshold.

[0049] In the embodiments of this application, the first SOC threshold and the second SOC threshold may be different based on the characteristics of different electrochemical systems and electrochemical devices.

[0050] For example, when the electrochemical device is a lithium iron phosphate system electrochemical device, the first SOC threshold is 30% to 70% (SOC), for example, 30%, 40%, 50%, 60% or 70%, and the second SOC threshold is 20% to 60%, for example, 20%, 30%, 40%, 50% or 60%.

[0051] When the electrochemical device is a lithium nickel cobalt manganese oxide system electrochemical device, the first SOC threshold is 20% to 50%, for example, 20%, 30%, 40% or 50%, and the second SOC threshold is 10% to 40%, for example, 10%, 30% or 40%.

[0052] The electrochemical device is a lithium cobalt oxide system electrochemical device, with a first SOC threshold of 20% to 50%, for example, 20%, 30%, 40% or 50%, and a second SOC threshold of 10% to 40%, for example, 10%, 30% or 40%.

[0053] By setting different first and second SOC thresholds for electrochemical devices with different electrochemical systems, lithium plating reduction strategies for different electrochemical systems can be optimized more effectively, thereby reducing lithium plating in different electrochemical systems and extending the safe service life of different electrochemical systems.

[0054] In one embodiment of this application, the method further includes:

[0055] In response to the lithium plating SOC being less than or equal to a second SOC threshold, the electrochemical device is controlled to stop operating; and a prompt message is generated.

[0056] In this embodiment, when the lithium plating SOC is less than or equal to the second SOC threshold, it indicates that the lithium plating SOC of the electrochemical device has become very small, and the performance of the electrochemical device has degraded significantly. Therefore, the electrochemical device can be controlled to stop being used, and the user can be prompted to replace the electrochemical device or scrap the electrochemical device. This allows the user to be promptly informed that the electrochemical device is no longer usable due to performance degradation, thus improving the user experience.

[0057] In one embodiment of this application, the electrochemical device management method further includes: in response to a lithium plating SOC being greater than a third SOC threshold and less than or equal to a second SOC threshold, reducing at least one of the charging voltage or charging current of the electrochemical device.

[0058] This application embodiment can set a third SOC threshold, wherein the second SOC threshold is greater than the third SOC threshold. Thus, after the electrochemical device performs intermittent charging, if the lithium plating SOC of the electrochemical device meets the above conditions, this application embodiment reduces the risk of lithium plating occurring due to continued operation at the current voltage and / or current by lowering the charging voltage of the electrochemical device, or lowering the charging current of the electrochemical device, or simultaneously lowering both the charging voltage and charging current of the electrochemical device, thereby improving the safety of the electrochemical device.

[0059] The aforementioned SOC threshold can be a pre-set threshold. The SOC threshold can be stored in advance in a storage medium connected to the electrochemical device. The SOC threshold is generally set based on the SOC of an electrochemical device sample exhibiting lithium plating within the same electrochemical system. For example, the SOC threshold can be set to the SOC corresponding to the occurrence of lithium plating in an electrochemical device sample. Different SOC thresholds are typically set for electrochemical devices with different electrochemical systems. For the same electrochemical device sample, the measured SOC corresponding to the occurrence of lithium plating will also differ at different charge / discharge rates and / or ambient temperatures.

[0060] In one embodiment of this application, the step of reducing at least one of the charging voltage or charging current of the electrochemical device includes:

[0061] i-1 reduces the current charging voltage of the electrochemical device by a first reduction to a first charging voltage, which is the updated current charging voltage;

[0062] And / or,

[0063] i-2 reduces the current charging current of the electrochemical device to the first charging current by a second reduction, the first charging current being the updated current charging current.

[0064] Embodiments of this application can reduce the charging voltage and / or charging current of an electrochemical device. In one example, when reducing the charging voltage of the electrochemical device, the current charging voltage can be reduced by a first decrease at a first temperature to obtain a first voltage, which is the updated current charging voltage. The first decrease can be from 0.01V to 1V, for example, 0.01V, 0.025V, 0.05V, 0.1V, or 1V.

[0065] In another example, when reducing the charging current of the electrochemical device, the current charging current can be reduced by a second reduction at a first temperature to obtain an updated current charging current. The second reduction can be the product of the battery's rated capacity and a first coefficient, which is between 0.05 and 0.15, for example, 0.05, 0.08, 0.1, 0.12, or 0.15. Of course, both the charging voltage and charging current of the electrochemical device can also be reduced simultaneously.

[0066] In one embodiment of this application, the method further includes:

[0067] ii-1 reduces the second SOC threshold and the third SOC threshold by the third reduction rate respectively, to obtain the updated second SOC threshold and the updated third SOC threshold;

[0068] iii-1 The electrochemical device is subjected to a third charge-discharge cycle using the charging current;

[0069] In response to the completion of the third charge-discharge cycle of the electrochemical device, iv-1 performs an intermittent charging operation on the electrochemical device again, acquires data related to the electrochemical device during the intermittent charging operation, determines the lithium plating SOC of the electrochemical device based on the data related to the electrochemical device, and judges the relationship between the lithium plating SOC and the updated second SOC threshold and the updated third SOC threshold.

[0070] v-1 When the lithium plating SOC is greater than the updated third SOC threshold and less than the updated second SOC threshold, repeat steps i-1 to iv-1 until the difference between the current charging voltage and the initial charging voltage of the electrochemical device is greater than the voltage difference threshold, and generate a prompt message. In the embodiments of this application, steps i-1 to iv-1 include: step i-1, step ii-1, step iii-1, and step iv-1.

[0071] In this embodiment, after reducing the charging voltage, the second and third SOC thresholds can be reduced by a third reduction rate to obtain updated second and third SOC thresholds. Thus, as the electrochemical device is used, after completing the third charge-discharge cycle at the first temperature, it triggers intermittent charging again and performs lithium plating detection. When the lithium plating SOC of the electrochemical device is greater than the updated third SOC threshold but less than the updated second SOC threshold, the current charging voltage is reduced again by the first reduction rate, and so on. This extends the lifespan of the electrochemical device and improves the user experience. The third reduction rate can be 1% to 10%, for example, 1%, 2.5%, 5%, or 10%.

[0072] In the third charge-discharge cycle, the electrochemical device can be charged using a pre-set charging current during the charging phase. Furthermore, the discharge current in the third charge-discharge cycle can be adapted to the electrical equipment; this application embodiment does not impose any limitations on this. The charging current in the third charge-discharge cycle of this application embodiment is not particularly limited; for example, it can be any current between 0.1A and 3A, such as 0.1A, 0.2A, 0.3A, 0.5A, 0.7A, 1A, 1.5A, 2A, 2.5A, or 3A.

[0073] As the charging voltage decreases, when the difference between the current charging voltage and the initial charging voltage of the electrochemical device exceeds a voltage difference threshold, it indicates significant performance degradation of the electrochemical device. This prompts the user to replace the device or even scrap it, allowing them to be promptly informed that the device is no longer usable due to performance degradation, thus improving the user experience. The aforementioned voltage difference threshold can be between 0.01V and 1V, for example, 0.01V, 0.1V, 0.5V, or 1V. The initial charging voltage can be the initial full charge voltage, i.e., the voltage at 100% SOC of the electrochemical device.

[0074] In one embodiment, the electrochemical device management method of this application may further include:

[0075] ii-2 In response to the completion of the third charge-discharge cycle of the electrochemical device, the electrochemical device is intermittently charged again. During the intermittent charging operation, data related to the electrochemical device is acquired. Based on the data related to the electrochemical device, the lithium plating SOC of the electrochemical device is determined, and the relationship between the lithium plating SOC and the second SOC threshold and the third SOC threshold is determined.

[0076] iii-2 When the lithium plating SOC is greater than the third SOC threshold and less than the second SOC threshold, repeat steps i-2 to ii-2 until the difference between the current charging current and the initial charging current of the electrochemical device is greater than the current difference threshold, and generate a prompt message.

[0077] In this embodiment, after reducing the charging current, as the electrochemical device is used, after the electrochemical device completes the third charge-discharge cycle, it triggers intermittent charging operation again and performs lithium plating detection. When the lithium plating SOC of the electrochemical device is greater than the third SOC threshold but less than the second SOC threshold, the current charging current is reduced again by the second reduction rate, and so on, thereby extending the service life of the electrochemical device and improving the user experience.

[0078] As the charging current decreases, when the difference between the current charging current and the initial charging current of the electrochemical device exceeds a current difference threshold, it indicates significant performance degradation of the electrochemical device. This prompts the user to replace the electrochemical device or to scrap it. This allows users to be promptly informed that the electrochemical device is no longer usable due to performance degradation, improving the user experience. The aforementioned current difference threshold is the product of a second coefficient and the rated capacity of the electrochemical device, where the second coefficient is between 0.1 and 0.5, for example, 0.1, 0.2, 0.25, 0.4, or 0.5.

[0079] In one embodiment of this application, heating elements are provided inside the electrochemical device and / or on the outer surface of the electrochemical device to effectively heat the electrochemical device and reduce the generation of reversible lithium plating.

[0080] In this embodiment, the electrochemical device can refer to a single battery, and the heating element can be disposed inside the electrochemical device and / or on its outer surface. When the heating element is disposed inside the electrochemical device, it can be sheet-like; preferably, the heating element is located outside the negative electrode sheet of the electrochemical device. The heating element is provided with terminals for connection to an external current. Alternatively, multiple electrochemical devices can form a battery module, with the heating element 2 disposed on the outer surface of the electrochemical device 1. When the heating element is disposed on the outer surface of the electrochemical device, in one example, such as... Figure 2 As shown, heating element 2 can be disposed between electrochemical devices 1; in another example, such as Figure 3 As shown, the heating element 2 is disposed in the gap between the battery module 3 and the electrochemical device 1, specifically, it can be the gap between the casing (e.g., packaging bag) of the battery module 3 and the electrochemical device 1. Adaptively, in one embodiment, the heating element is provided with a switch, and the management unit can control the opening and closing of the switch to enable or disable the heating element. The heating element can heat the electrochemical device based on an external current, or it can utilize the current generated by the electrochemical device for heating.

[0081] The heating element in this application embodiment is made of at least one of nickel, nickel-aluminum alloy, copper, polyimide (PI), silicone, or PTC (Positive Temperature Coefficient) material. This application embodiment does not limit the structure of the heating element, as long as it achieves the purpose of this application; for example, the heating element can be sheet-like, film-like, etc. The impedance of the heating element in this application embodiment ranges from 0.01Ω to 50Ω, preferably from 0.2Ω to 5Ω, exhibiting good heating performance, thereby effectively reducing reversible lithium plating in the electrochemical device.

[0082] In one embodiment of this application, the data associated with the electrochemical device include the state of charge (SOC) and internal resistance of the electrochemical device, and the intermittent charging operation includes multiple charging periods and multiple interruption periods.

[0083] Intermittent charging operation can refer to the process of intermittently charging an electrochemical device. Data related to the electrochemical device can refer to data that reflects the state of the electrochemical device. The state of charge (SOC) of lithium plating in the electrochemical device is determined in the following way:

[0084] Step A: During the intermittent charging operation, for each of the multiple intermittent periods, obtain the SOC and internal resistance of the electrochemical device during that intermittent period;

[0085] In intermittent charging operations, the internal resistance of the electrochemical device can be determined based on the detected charging voltage and charging current. The battery management system can pre-store a voltage-SOC relationship table, which records the SOC of the electrochemical device corresponding to different charging voltages; for example, 4.2V corresponds to 85% SOC, and 4.3V corresponds to 90% SOC. Therefore, the SOC of the electrochemical device can be determined based on the charging voltage and the voltage-SOC relationship table.

[0086] Step B: Based on the multiple SOCs of the obtained electrochemical device and the multiple internal resistances of the electrochemical device corresponding to the multiple SOCs, the first curve is obtained;

[0087] In this embodiment of the application, after obtaining the SOC and internal resistance during multiple intermittent periods of the electrochemical device, multiple data pairs consisting of SOC and internal resistance can be obtained, which can be referenced. Figure 4 We can use the SOC of the electrochemical device as the abscissa and the internal resistance of the electrochemical device as the ordinate, fill the points represented by these data pairs into the coordinate system, and obtain the first curve after fitting. The first curve represents the mapping curve between the SOC and the internal resistance of the electrochemical device.

[0088] It is understandable that the more intensive the acquisition of SOC and internal resistance data for the electrochemical device, the more data pairs are obtained, resulting in a more detailed first curve. In this embodiment, it is not necessarily required to acquire SOC and internal resistance data for all interruptions. That is, "each interruption" can refer to any interruption during which SOC and internal resistance data have already been acquired, rather than requiring the acquisition of SOC and internal resistance data for all interruptions. As long as a sufficient number of SOC and internal resistance data points are acquired to obtain the first curve, it is acceptable. The process of curve fitting using data is well known to those skilled in the art, and the comparison of embodiments in this application does not impose specific limitations.

[0089] Step C: Based on the first curve, determine the state of lithium plating (SOC) of the electrochemical device.

[0090] The first curve represents the mapping relationship between the SOC and internal resistance of the electrochemical device. The lithium plating SOC of the electrochemical device can be determined based on the first curve.

[0091] The aforementioned lithium plating SOC may not be measured in real time, but rather derived from the charging voltage obtained during intermittent charging operations and a voltage-SOC relationship table. This voltage-SOC relationship table can be pre-stored in the storage medium of the battery management system. Steps A to C above are only used to illustrate the order of the steps, not to limit the order of the steps.

[0092] In one embodiment, the process of determining the lithium plating state of the electrochemical device based on the first curve can be method 1, which includes:

[0093] i: Take the first derivative of the first curve to obtain the second curve;

[0094] like Figure 5 As shown, the second curve is obtained by taking the first derivative of the first curve. This second curve represents the rate of change of the internal resistance of the electrochemical device with SOC.

[0095] ii: Determine the SOC corresponding to the point where the slope of the second curve first appears negative as the lithium plating SOC.

[0096] The second curve represents the rate of change of internal resistance with SOC. When the rate of change does not show an abnormal decrease in the flat region of the curve, it indicates that no active lithium has been deposited. When the rate of change shows an abnormal decrease in the flat region of the curve, it is because active lithium has been deposited on the surface of the negative electrode and is in contact with the negative electrode. This is equivalent to a lithium metal device being connected in parallel with the graphite part of the negative electrode, which reduces the impedance of the entire negative electrode. Therefore, the impedance of the electrochemical device shows an abnormal decrease when active lithium is deposited, and correspondingly, the flat region of the second curve shows an abnormal decrease. (Reference) Figure 5Point B is the first point in the second curve where the slope is negative. That is, the flat area of ​​the second curve at point B shows an abnormal decrease for the first time, indicating that the electrochemical device has a tendency to or has already undergone lithium plating at point B. The SOC corresponding to point B can be determined as the lithium plating SOC. Based on the relationship between the lithium plating SOC and the SOC threshold, lithium plating reduction operations can be performed on the electrochemical device in a timely manner to improve the safety of the electrochemical device.

[0097] In one implementation, the process of determining the lithium plating state of the electrochemical device based on the first curve can be method 2, which includes:

[0098] i': Take the first derivative of the first curve to obtain the second curve;

[0099] This step is the same as step i in method 1, and will not be repeated here.

[0100] ii': Taking the second derivative of the second curve yields the third curve;

[0101] The second curve can also be differentiated by its second order to obtain the third curve. It can be understood that the third curve is the second-order differential curve of the second curve.

[0102] iii': Determine the SOC corresponding to the point where the ordinate of the third curve first appears to be less than zero as the lithium plating SOC.

[0103] If the ordinate of the third curve is less than zero, the SOC corresponding to the first point where the ordinate of the third curve is less than zero is determined as the lithium plating SOC. In this embodiment, the ordinate of the third curve is the second-order differential internal resistance, and the abscissa of the third curve is the SOC.

[0104] Intermittent charging operation can refer to the process of intermittently charging an electrochemical device. In one embodiment, intermittent charging operation may include multiple charging cycles, each charging cycle comprising a charging period and an intermittent period, during which the state of charge (SOC) of the electrochemical device increases by a unit increment. That is, the SOC of the electrochemical device is increased by a certain increment during each charging period. For example, the SOC may be increased by 0.5%, 1%, 5%, or 10% during each charging period.

[0105] In one implementation, the intermittent charging operation can be specifically described as follows: For any one of multiple charging cycles, the electrochemical device is charged at a first moment until the State of Charge (SOC) of the electrochemical device increases by a unit magnitude, at which point charging stops, until a third moment. The moment at which charging stops is the second moment, and the time interval between the third moment and the second moment is the duration of the intermittent period. During the intermittent period, the electrochemical device can be in a state of neither charging nor discharging, i.e., a static state.

[0106] For example, if the electrochemical device is charged at time T1 until the state of charge (SOC) of the electrochemical device increases by a unit magnitude, and then the charging stops, the time when the charging stops is time T2; starting from time T2, the electrochemical device is left to stand, and the time when the standing ends is time T3.

[0107] The electrochemical device in this application includes at least one of a lithium iron phosphate system electrochemical device, a nickel-cobalt-manganese oxide system electrochemical device, or a lithium cobalt oxide system electrochemical device. Generally, in intermittent charging operations, electrochemical devices with different electrochemical systems correspond to different unit amplitudes and different intermittent periods. Based on this:

[0108] In one embodiment, the electrochemical device is a lithium iron phosphate system electrochemical device, with a unit amplitude ranging from 0.5% to 10% and an intermittent period duration ranging from 1 second to 15 seconds.

[0109] In one embodiment, the electrochemical device is a lithium nickel cobalt manganese oxide system electrochemical device, with a unit amplitude ranging from 0.5% to 10% and an intermittent period duration ranging from 1 second to 30 seconds.

[0110] In one embodiment, the electrochemical device is a lithium cobalt oxide system electrochemical device, with a unit amplitude ranging from 0.5% to 10% and an intermittent period duration ranging from 1 second to 30 seconds.

[0111] This application embodiment sets different unit amplitudes and intermittent periods for electrochemical devices of different electrochemical systems, enabling more targeted intermittent charging operations for these devices and more accurately obtaining the lithium plating SOC of the electrochemical devices of different electrochemical systems.

[0112] Generally speaking, in intermittent charging operations, for the same electrochemical system, different temperature conditions will correspond to different unit amplitudes and different durations of interruptions. Based on this:

[0113] In one embodiment, the electrochemical device is a lithium iron phosphate system electrochemical device, operating at an ambient temperature of -10°C to 10°C, with a unit amplitude ranging from 0.5% to 10%, and an intermittent period duration ranging from 5 seconds to 15 seconds. In another embodiment, the electrochemical device is a lithium iron phosphate system electrochemical device, operating at an ambient temperature of 10°C to 45°C, with a unit amplitude ranging from 0.5% to 10%, and an intermittent period duration ranging from 1 second to 10 seconds.

[0114] In the embodiments of this application, the positive electrode of the lithium iron phosphate system electrochemical device may also include other positive electrode active materials, but lithium iron phosphate is the main material. For example, lithium iron phosphate accounts for any one of 51%, 60%, 70%, 80%, 90%, or 98% of the total mass of the positive electrode active material.

[0115] In one embodiment, the electrochemical device is a lithium nickel cobalt manganese oxide system electrochemical device, operating at an ambient temperature of -10°C to 10°C, with a unit amplitude ranging from 0.5% to 10%, and an intermittent period duration ranging from 10 seconds to 30 seconds. In another embodiment, the electrochemical device is a lithium nickel cobalt manganese oxide system electrochemical device, operating at an ambient temperature of 10°C to 45°C, with a unit amplitude ranging from 0.5% to 10%, and an intermittent period duration ranging from 1 second to 10 seconds.

[0116] In the embodiments of this application, the positive electrode of the lithium nickel cobalt manganese oxide system electrochemical device may also include other positive electrode active materials, but lithium nickel cobalt manganese oxide is the main material. For example, lithium nickel cobalt manganese oxide accounts for any of the following values ​​of the total mass of the positive electrode active material: 51%, 60%, 70%, 80%, 90%, and 98%.

[0117] In one embodiment, the electrochemical device is a lithium cobalt oxide system electrochemical device, operating at an ambient temperature of -10°C to 10°C, with a unit amplitude ranging from 0.5% to 10%, and an intermittent period duration ranging from 15 seconds to 30 seconds. In another embodiment, the electrochemical device is a lithium cobalt oxide system electrochemical device, operating at an ambient temperature of 10°C to 45°C, with a unit amplitude ranging from 0.5% to 10%, and an intermittent period duration ranging from 1 second to 10 seconds.

[0118] In the embodiments of this application, the positive electrode of the lithium cobalt oxide system electrochemical device may also include other positive electrode active materials, but lithium cobalt oxide is the main material. For example, lithium cobalt oxide accounts for any of the following values ​​of the total mass of the positive electrode active material: 51%, 60%, 70%, 80%, 90%, and 98%.

[0119] In one implementation, the electrochemical devices belonging to the same battery module have the same electrochemical system, which ensures good consistency among the electrochemical devices in the battery module.

[0120] This application embodiment sets different unit amplitudes and intermittent durations for electrochemical devices in the same electrochemical system at different temperatures, enabling more targeted intermittent charging operations for electrochemical devices in different temperature environments, and thus more accurately obtaining the lithium plating SOC of electrochemical devices in different electrochemical systems.

[0121] This application provides an electrochemical device management method, system, electrochemical device, and electronic device. After performing a first charge-discharge cycle on the electrochemical device with a charging current, the device is intermittently charged. During the intermittent charging operation, data related to the electrochemical device is acquired. Based on this data, the lithium plating state of the electrochemical device is determined, which can accurately detect the risk of lithium plating in the battery and improve the safety of the electrochemical device during use. In response to the lithium plating state of the electrochemical device being less than or equal to a first state of the charge-discharge threshold, the electrochemical device is controlled to perform a lithium plating reduction operation, that is, the electrochemical device is controlled to perform a second charge-discharge cycle at a first charge-discharge rate at a first temperature, which can reduce the lithium plating that has been generated by the electrochemical device and improve the safety of the electrochemical device during use.

[0122] This application also provides a system including a processor and a machine-readable storage medium, wherein the machine-readable storage medium stores machine-executable instructions that can be executed by the processor, and when the processor executes the machine-executable instructions, it implements the electrochemical device management method described in any of the above embodiments.

[0123] This application also provides a system, such as Figure 6 As shown, the system 400 includes a charge / discharge device 401, a SOC analysis device 402, and a management unit 403. The charge / discharge device 401 is used to perform a first charge / discharge cycle on the electrochemical device with a charging current. The SOC analysis device 402 is used to perform intermittent charging operation on the electrochemical device, acquire data related to the electrochemical device during the intermittent charging operation, and determine the lithium plating SOC of the electrochemical device based on the data related to the electrochemical device. The management unit 403 is used to control the electrochemical device to perform a lithium plating reduction operation or control the electrochemical device to stop working in response to the lithium plating SOC being less than or equal to a first SOC threshold. The lithium plating reduction operation includes controlling the electrochemical device to perform a second charge / discharge cycle at a first charge / discharge rate at a first temperature.

[0124] In one embodiment, the management unit is specifically configured to: control the electrochemical device to perform a lithium plating reduction operation in response to a lithium plating SOC being greater than a second SOC threshold and less than or equal to a first SOC threshold, wherein the second SOC threshold is less than the first SOC threshold.

[0125] In one implementation, the management unit is also configured to: control the electrochemical device to stop operating in response to a lithium plating SOC being less than or equal to a second SOC threshold; and generate a prompt message.

[0126] In one embodiment, the management unit is further configured to: reduce at least one of the charging voltage or charging current of the electrochemical device in response to a lithium plating SOC being greater than a third SOC threshold and less than or equal to a second SOC threshold.

[0127] In one embodiment, the management unit is specifically configured to: reduce the current charging voltage of the electrochemical device by a first reduction to a first charging voltage, wherein the first charging voltage is the updated current charging voltage;

[0128] And / or, reduce the current charging current of the electrochemical device to a first charging current by a second reduction, the first charging current being the updated current charging current.

[0129] In one embodiment, heating elements are provided inside the electrochemical device and / or on the outer surface of the electrochemical device.

[0130] In one embodiment, the heating element is made of at least one of nickel, nickel-aluminum alloy, copper, polyimide, silicone, or a positive temperature coefficient material; the impedance of the heating element ranges from 0.01Ω to 50Ω.

[0131] In one embodiment, the first temperature ranges from 30°C to 70°C, and the first charge / discharge rate ranges from 0.01C to 0.5C.

[0132] In one embodiment, data related to the electrochemical device includes the state of charge (SOC) and internal resistance of the electrochemical device, the intermittent charging operation includes multiple charging periods and multiple interruptions, and the SOC analysis device is specifically used for:

[0133] During intermittent charging operation, for each of the multiple intermittent periods, the SOC and internal resistance of the electrochemical device during the intermittent period are obtained. Based on the multiple SOCs of the electrochemical device and the multiple internal resistances of the electrochemical device corresponding to the multiple SOCs, a first curve is obtained. The first curve is a mapping curve corresponding to the SOC and internal resistance of the electrochemical device. Based on the first curve, the lithium plating SOC of the electrochemical device is determined.

[0134] In one implementation, the lithium plating SOC analysis device is specifically used for:

[0135] The first curve is differentiated to obtain the second curve; the SOC corresponding to the first point on the second curve with a negative slope is determined to be the lithium plating SOC.

[0136] Alternatively, perform a first-order differential on the first curve to obtain the second curve; perform a second-order differential on the second curve to obtain the third curve; determine the SOC corresponding to the first point on the third curve where the ordinate is less than zero as the lithium plating SOC.

[0137] In one embodiment, the intermittent charging operation includes multiple charging cycles, each charging cycle including a charging period and an intermittent period, during which the SOC of the electrochemical device increases by a unit magnitude.

[0138] In one embodiment, the electrochemical device includes at least one of a lithium iron phosphate system electrochemical device, a lithium nickel cobalt manganese oxide system electrochemical device, or a lithium cobalt oxide system electrochemical device, wherein...

[0139] The electrochemical devices are lithium iron phosphate system electrochemical devices with a unit amplitude range of 0.5% to 10% and an intermittent period duration range of 1 second to 15 seconds; the electrochemical devices are nickel cobalt manganese oxide system electrochemical devices with a unit amplitude range of 0.5% to 10% and an intermittent period duration range of 1 second to 30 seconds; the electrochemical devices are lithium cobalt oxide system electrochemical devices with a unit amplitude range of 0.5% to 10% and an intermittent period duration range of 1 second to 30 seconds.

[0140] In one embodiment, the lithium plating SOC analysis device is specifically used for any one of the following a) to f):

[0141] a) The electrochemical device is a lithium iron phosphate system electrochemical device, operating at an ambient temperature of -10℃ to 10℃, with a unit amplitude range of 0.5% to 10%, and an intermittent duration range of 5 to 15 seconds; b) The electrochemical device is a lithium iron phosphate system electrochemical device, operating at an ambient temperature of 10℃ to 45℃, with a unit amplitude range of 0.5% to 10%, and an intermittent duration range of 1 to 10 seconds; c) The electrochemical device is a lithium nickel cobalt manganese oxide system electrochemical device, operating at an ambient temperature of -10℃ to 10℃, with a unit amplitude range of 0.5% to 10%, and an intermittent duration range of 10 to 30 seconds. d) The electrochemical device is a lithium nickel cobalt manganese oxide system electrochemical device, the electrochemical device is in an ambient temperature of 10℃ to 45℃, the unit amplitude ranges from 0.5% to 10%, and the duration of the intermittent period ranges from 1 second to 10 seconds; e) The electrochemical device is a lithium cobalt oxide system electrochemical device, the electrochemical device is in an ambient temperature of -10℃ to 10℃, the unit amplitude ranges from 0.5% to 10%, and the duration of the intermittent period ranges from 15 seconds to 30 seconds; f) The electrochemical device is a lithium cobalt oxide system electrochemical device, the electrochemical device is in an ambient temperature of 10℃ to 45℃, the unit amplitude ranges from 0.5% to 10%, and the duration of the intermittent period ranges from 1 second to 10 seconds.

[0142] The system provided in this application embodiment includes a charging and discharging device that performs a first charge-discharge cycle on an electrochemical device using a charging current. The SOC analysis device then performs intermittent charging on the electrochemical device, acquiring data related to the device during this intermittent charging process. Based on this data, the system determines the lithium plating SOC of the electrochemical device, accurately detecting the risk of lithium plating in the battery and improving the safety of the electrochemical device during use. The management unit, in response to the lithium plating SOC being less than or equal to a first SOC threshold, controls the electrochemical device to perform a lithium plating reduction operation. Specifically, it controls the electrochemical device to perform a second charge-discharge cycle at a first charge-discharge rate at a first temperature, reducing the lithium plating already generated in the electrochemical device and further improving its safety during use.

[0143] This application also provides a battery module, including the system described in the above embodiments.

[0144] This application also provides an electronic device, including the battery module described in the above embodiments.

[0145] This application also provides a charging device, including a processor and a machine-readable storage medium. The machine-readable storage medium stores machine-executable instructions that can be executed by the processor. When the processor executes the machine-executable instructions, it implements the electrochemical device management method described in any of the above embodiments.

[0146] In one example, refer to Figure 7 The charging device includes a housing 4 and a heating element 2. The housing 4 can accommodate a battery module 3, and the heating element 2 is disposed between the housing 4 and the battery module 3. Specifically, the heating element 2 can be disposed on the inner wall of the housing 4. The heating element 2 may also be equipped with a switch; when heating is required, the control unit controls the switch to close, energizing the heating element 2 to begin heating, thus raising the temperature of the battery module 3 and performing a lithium plating reduction operation.

[0147] This application also provides a charging device, such as... Figure 8As shown, the charging device 500 includes a processor 501 and a machine-readable storage medium 502. The charging device 500 may also include a detection circuit module 503, a charge / discharge circuit 504, an interface 505, a power interface 506, and a rectifier circuit 507. The charge / discharge circuit 504 receives instructions from the processor 501 to charge and discharge the lithium-ion battery 605. The detection circuit module 503 performs intermittent charging of the lithium-ion battery 605 to detect the state of charge (SOC) of the electrochemical device and sends the detection result to the processor 501. The interface 505 is electrically connected to the lithium-ion battery 605. The power interface 506 is connected to an external power source. The rectifier circuit 507 rectifies the input current. The machine-readable storage medium 502 stores machine-executable instructions that can be executed by the processor. When the processor 501 executes the machine-executable instructions, it implements the steps described in any of the above embodiments.

[0148] The memory may include random access memory (RAM) or non-volatile memory (NVM), such as at least one disk storage device. Optionally, the memory may also be at least one storage device located remotely from the aforementioned processor.

[0149] The processors mentioned above can be general-purpose processors, including central processing units (CPUs), network processors (NPs), etc.; they can also be digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0150] For the system / battery module / electronic device embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and relevant parts can be referred to in the description of the method embodiments.

[0151] Preparation Example 1

[0152] Preparation of electrochemical devices based on lithium nickel cobalt manganese oxide system :

[0153] Preparation of the positive electrode sheet: Lithium nickel cobalt manganese oxide, acetylene black, and polyvinylidene fluoride (PVDF) were mixed in a mass ratio of 94:3:3. N-methylpyrrolidone (NMP) was then added as a solvent to prepare a slurry with a solid content of 75%, and the mixture was stirred evenly. The slurry was uniformly coated onto one surface of a 12 μm thick aluminum foil, dried at 90°C, and cold-pressed to obtain a positive electrode sheet with a 100 μm thick positive active material layer. The above steps were repeated on the other surface of the same positive electrode sheet to obtain a positive electrode sheet with positive active material layers coated on both sides. The positive electrode sheet was cut to a size of (74 mm × 867 mm) and tabs were welded on for later use.

[0154] Preparation of the negative electrode sheet: Artificial graphite, acetylene black, styrene-butadiene rubber, and sodium carboxymethyl cellulose (CMC) were mixed in a mass ratio of 96:1:1.5:1.5. Deionized water was then added as a solvent to prepare a slurry with a solid content of 70%, and the mixture was stirred evenly. The slurry was uniformly coated onto one surface of an 8 μm thick copper foil, dried at 110°C, and cold-pressed to obtain a single-sided negative electrode sheet with a 150 μm thick negative active material layer. The coating process was repeated on the other surface of the same negative electrode sheet to obtain a double-sided negative electrode sheet. The negative electrode sheet was cut to a size of 74 mm × 867 mm and tabs were welded on for later use.

[0155] Preparation of the separator: A porous polyethylene (PE) film with a thickness of 15 μm was used as the separator.

[0156] Preparation of electrolyte: In an environment with a water content of less than 10 ppm, non-aqueous organic solvents ethylene carbonate (EC), propylene carbonate (PC), and diethyl carbonate (DEC) were mixed in a mass ratio of 1:1:1. Then, lithium hexafluorophosphate (LiPF6) was added to the non-aqueous organic solvents, dissolved, and mixed evenly to obtain the electrolyte, wherein the concentration of LiPF6 was 1.15 mol / L.

[0157] Preparation of an electrochemical device with a heating element: The prepared positive electrode, separator, and negative electrode are stacked in sequence, with the separator positioned between the positive and negative electrodes to provide isolation. The heating element (impedance selectable) is placed in the innermost layer of the electrochemical device, i.e., in the middle of the first turn of the separator, and then wound to obtain the electrode assembly. The electrode assembly is placed in an aluminum-plastic film packaging bag and dehydrated at 80°C. The prepared electrolyte is then injected, and after vacuum sealing, settling, formation, and shaping, the electrochemical device with a rated capacity of 5Ah is obtained.

[0158] Preparation Example 2

[0159] Preparation of electrochemical devices based on lithium iron phosphate system :

[0160] Preparation of the positive electrode sheet: Lithium iron phosphate, acetylene black, and polyvinylidene fluoride (PVDF) were mixed in a mass ratio of 94:3:3. N-methylpyrrolidone (NMP) was then added as a solvent to prepare a slurry with a solid content of 75%, and the mixture was stirred evenly. The slurry was uniformly coated onto one surface of a 12 μm thick aluminum foil, dried at 90°C, and cold-pressed to obtain a positive electrode sheet with a 100 μm thick positive active material layer. The above steps were repeated on the other surface of the same positive electrode sheet to obtain a positive electrode sheet with positive active material layers coated on both sides. The positive electrode sheet was cut to a size of 74 mm × 867 mm and tabs were welded on for later use.

[0161] The preparation methods for the negative electrode, the separator, the electrolyte, and the electrochemical device are the same as in Preparation Example 1. The rated capacity of the electrochemical device is 4 Ah.

[0162] Preparation Example 3

[0163] Preparation of an electrochemical device using a mixed system of lithium cobalt oxide and lithium iron phosphate:

[0164] Preparation of the positive electrode sheet: Lithium cobalt oxide, lithium iron phosphate, acetylene black, and polyvinylidene fluoride (PVDF) were mixed at a mass ratio of 94:3:3 (where the mass ratio of lithium cobalt oxide to lithium iron phosphate was 1:1). N-methylpyrrolidone (NMP) was then added as a solvent to prepare a slurry with a solid content of 75%, and the mixture was stirred evenly. The slurry was uniformly coated onto one surface of a 12 μm thick aluminum foil, dried at 90°C, and cold-pressed to obtain a positive electrode sheet with a 100 μm thick positive active material layer. The above steps were repeated on the other surface of the same positive electrode sheet to obtain a positive electrode sheet with a double-sided coating of positive active material layers. The positive electrode sheet was cut to a size of 74 mm × 867 mm and tabs were welded on for later use.

[0165] The preparation methods for the negative electrode, the separator, the electrolyte, and the electrochemical device are the same as in Preparation Example 1. The rated capacity of the electrochemical device is 4.5 Ah.

[0166] Example 1

[0167] <Heating element settings>

[0168] Two electrochemical devices were prepared according to the method of Preparation Example 1, and the two electrochemical devices were connected in series to form a battery module. Each electrochemical device had a nickel heating element with an impedance of 2Ω installed in its innermost layer.

[0169] <Detection of Lithium Plating SOC>

[0170] The electrochemical device was subjected to charge-discharge cycles, with intermittent charging during each charge operation until lithium plating at the state of charge (SOC) was detected. The charge-discharge cycle procedure was as follows: the electrochemical device was charged at a constant current rate of 1C to 4.4V, then charged at a constant voltage until the charging current dropped to 250mA, allowed to rest for 15 minutes, and then discharged at a constant current rate of 5A to 2.8V, allowed to rest for 15 minutes. The first discharge capacity was recorded as Q0, and the discharge capacity of each subsequent charge-discharge cycle was recorded as Q. n Then the capacity retention rate for the nth charge-discharge cycle is: Q n / Q0×100%.

[0171] <Protection Operation of Electrochemical Devices>

[0172] If the SOC of lithium plating exceeds the first SOC threshold, control the normal operation of the electrochemical device;

[0173] If the second SOC threshold < lithium plating SOC ≤ first SOC threshold, a lithium plating reduction operation is performed on the electrochemical device: the electrochemical device is controlled to undergo 9 second charge-discharge cycles at 0.01C at 35°C, thereby reducing lithium plating in the electrochemical device;

[0174] If the SOC of lithium plating is less than or equal to the second SOC threshold, the electrochemical device will be shut down and the user will be prompted to replace it.

[0175] The first SOC threshold was 30%, and the second SOC threshold was 29%. The lithium plating SOC, the number of charge-discharge cycles, and the capacity retention rate of the last charge-discharge cycle of the electrochemical device were recorded.

[0176] Example 2

[0177] Besides the nickel heating element being placed between the electrochemical devices, forming a structure like... Figure 2 Except for the structure shown, it is the same as in Example 1.

[0178] Example 3

[0179] Besides the gap between the casing where the battery module is housed and the electrochemical device, forming a space like... Figure 3 Except for the structure shown, it is the same as in Example 1.

[0180] Example 4

[0181] In addition to placing electrochemical devices in, for example Figure 7 In the charging device shown, apart from the nickel heating element placed on the inner wall of the charging device, everything else is the same as in Example 1.

[0182] Example 5

[0183] The settings for heating elements and the detection of lithium plating SOC are the same as in Example 1.

[0184] <Protection Operation of Electrochemical Devices>

[0185] If the SOC of lithium plating exceeds the first SOC threshold, control the normal operation of the electrochemical device;

[0186] If the second SOC threshold < lithium plating SOC ≤ first SOC threshold, a lithium plating reduction operation is performed on the electrochemical device: the electrochemical device is controlled to undergo 6 second charge-discharge cycles at 0.5C at 45°C, thereby reducing lithium plating in the electrochemical device;

[0187] If the SOC of lithium plating is less than or equal to the third SOC threshold, the electrochemical device will be shut down and the user will be prompted to replace it.

[0188] If the third SOC threshold < lithium plating SOC ≤ second SOC threshold, the current charging voltage is reduced by 0.025V. During the next lithium plating detection, both the second and third SOC thresholds are reduced by 2.5%, and the relationship between the lithium plating SOC and the second and third SOC thresholds is reassessed, and so on. When the difference between the current charging voltage and the initial charging voltage of the electrochemical device exceeds the voltage difference threshold, the electrochemical device is stopped, and the user is prompted to replace it. The total number of cycles of the electrochemical device is recorded. The third SOC threshold is 10%, and the voltage difference threshold is 0.1V.

[0189] Example 6

[0190] The settings for heating elements and the detection of lithium plating SOC are the same as in Example 1.

[0191] <Protection Operation of Electrochemical Devices>

[0192] If the SOC of lithium plating exceeds the first SOC threshold, control the normal operation of the electrochemical device;

[0193] If the second SOC threshold < lithium plating SOC ≤ first SOC threshold, a lithium plating reduction operation is performed on the electrochemical device: the electrochemical device is controlled to undergo 7 second charge-discharge cycles at 0.3C at 55°C, thereby reducing lithium plating in the electrochemical device;

[0194] If the SOC of lithium plating is less than or equal to the third SOC threshold, the electrochemical device will be shut down and the user will be prompted to replace it.

[0195] If the third SOC threshold < lithium plating SOC ≤ second SOC threshold, the charging current is reduced by a first increment, which is 0.1 × electrochemical device capacity. The electrochemical device continues to be used, and the relationship between the lithium plating SOC and the second and third SOC thresholds is determined again during the next lithium plating detection, and so on. When the difference between the current charging current and the initial charging current of the electrochemical device is greater than the current difference threshold, the electrochemical device is stopped, and the user is prompted to replace the electrochemical device. The total number of cycles of the electrochemical device is recorded. The current difference threshold is calculated as: second coefficient × battery rated capacity. In this embodiment, the second coefficient is 0.25, and the rated capacity of the electrochemical device is 5Ah, so the current difference threshold is 0.25 × 5 = 1.25.

[0196] Example 7

[0197] Except for using the electrochemical apparatus of Preparation Example 2, in the <Detection of Lithium Plating SOC>, the charging voltage of the charge-discharge cycle operation was adjusted to 3.6V and the discharging voltage to 2.5V, otherwise it was the same as in Example 1.

[0198] Example 8

[0199] Except for the electrochemical device used in Preparation Example 3, the rest is the same as in Example 1.

[0200] Comparative Example 1

[0201] Except for the <protection operation of the electrochemical device>, which is different from Example 1, everything else is the same as Example 1.

[0202] <Protection Operation of Electrochemical Devices>

[0203] If the SOC of lithium plating exceeds the first SOC threshold, control the normal operation of the electrochemical device;

[0204] If the SOC of lithium plating is less than or equal to the second SOC threshold, the electrochemical device is shut down, and the total number of cycles of the electrochemical device is recorded.

[0205] Comparative Example 2

[0206] Except for the <Protection Operation of Electrochemical Device>, which differs from Comparative Example 1, everything else is the same as Comparative Example 1.

[0207] <Protection Operation of Electrochemical Devices>

[0208] If the SOC of lithium plating exceeds the first SOC threshold, control the normal operation of the electrochemical device;

[0209] If the lithium plating SOC is less than or equal to the third SOC threshold, the electrochemical device should be shut down.

[0210] If the third SOC threshold < lithium plating SOC ≤ second SOC threshold, the current charging voltage is reduced by 0.025V. During the next lithium plating detection, both the second and third SOC thresholds are reduced by 2.5%, and the relationship between the lithium plating SOC and the second and third SOC thresholds is determined again, and so on. When the difference between the current charging voltage and the initial charging voltage of the electrochemical device exceeds the voltage difference threshold, the electrochemical device is stopped, and the total number of cycles is recorded.

[0211] Comparative Example 3

[0212] Except for the <Protection Operation of Electrochemical Device>, which differs from Comparative Example 1, everything else is the same as Comparative Example 1.

[0213] <Protection Operation of Electrochemical Devices>

[0214] If the SOC of lithium plating exceeds the first SOC threshold, control the normal operation of the electrochemical device;

[0215] If the lithium plating SOC is less than or equal to the third SOC threshold, the electrochemical device should be shut down.

[0216] If the third SOC threshold < lithium plating SOC ≤ second SOC threshold, the charging current is reduced by a first increment, which is 0.1 × the capacity of the electrochemical device. The electrochemical device continues to operate, and the relationship between the lithium plating SOC and the second and third SOC thresholds is determined again during the next lithium plating detection, and so on. When the difference between the current charging current and the initial charging current of the electrochemical device exceeds the current difference threshold, the electrochemical device is stopped, and the total number of cycles of the electrochemical device is recorded.

[0217] Comparative Example 4

[0218] Except for using the electrochemical apparatus of Preparation Example 2, in the <Detection of Lithium Plating SOC>, the charging voltage of the charge-discharge cycle operation was adjusted to 3.6V and the discharging voltage to 2.5V, and the rest was the same as Comparative Example 1.

[0219] Comparative Example 5

[0220] Except for the electrochemical apparatus used in Preparation Example 3, it is the same as Comparative Example 1.

[0221] The data from Examples 1 to 8 and Comparative Examples 1 to 5 are shown in Table 1:

[0222] Table 1

[0223]

[0224]

[0225] As can be seen from Examples 1 and Comparative Examples 1, 5 and Comparative Examples 2, 6 and Comparative Examples 3, 7 and Comparative Examples 4, and 8 and Comparative Examples 5, the lithium plating SOC of the electrochemical devices detected in each example and comparative example is basically the same. When the electrochemical device decays to the same capacity retention rate, the number of cycles of the electrochemical device increases significantly. This indicates that the electrochemical device management method of the present application can effectively reduce the lithium plating generated by the electrochemical device, significantly improve the cycle life of the electrochemical device, and enhance the user experience.

[0226] As can be seen from Examples 1 to 4, when the heating element impedance is the same, the heating effect varies depending on the location of the heating element in the electrochemical device, and the effect of the lithium plating reduction operation on improving the lifespan of the electrochemical device also varies. The heating effect of the heating element is generally arranged in the following order: built into the electrochemical device > between electrochemical devices > gap between the battery module housing and the electrochemical device > between the charging device housing and the battery module. However, as can be seen from Examples 1 to 4 and Comparative Example 1, this application can increase the cycle number of the electrochemical device and thus improve the cycle life of the electrochemical device by setting a heating element to perform a lithium plating reduction operation on the electrochemical device.

[0227] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0228] The various embodiments in this specification are described in a related manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions of the method embodiments.

[0229] The above description is only a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A method for managing an electrochemical device, wherein, The method includes: The electrochemical device is subjected to a first charge-discharge cycle using a charging current. An intermittent charging operation is performed on an electrochemical device, during which data related to the electrochemical device is acquired, and the lithium plating state-of-the-art (SOC) of the electrochemical device is determined based on the data related to the electrochemical device. In response to the lithium plating SOC being greater than a second SOC threshold and less than or equal to a first SOC threshold, the electrochemical device is controlled to perform a lithium plating reduction operation, the lithium plating reduction operation including: The electrochemical device is controlled to perform a second charge-discharge cycle at a first charge-discharge rate at a first temperature, wherein the second SOC threshold is less than the first SOC threshold; wherein the first temperature ranges from 30°C to 70°C, and the first charge-discharge rate ranges from 0.01C to 0.5C.

2. The electrochemical device management method according to claim 1, wherein, The method further includes: In response to the lithium plating SOC being less than or equal to the second SOC threshold, the electrochemical device is controlled to stop operating; and Generate a prompt message.

3. The electrochemical device management method according to claim 1, wherein, The method further includes: In response to the lithium plating SOC being greater than a third SOC threshold and less than or equal to the second SOC threshold, at least one of the charging voltage or charging current of the electrochemical device is reduced.

4. The electrochemical device management method according to claim 3, wherein, The reduction of at least one of the charging voltage or charging current of the electrochemical device includes: i-1 reduces the current charging voltage of the electrochemical device by a first reduction to a first charging voltage, where the first charging voltage is the updated current charging voltage; And / or, i-2 reduces the current charging current of the electrochemical device to a first charging current with a second reduction rate, the first charging current being the updated current charging current.

5. The electrochemical device management method according to claim 4, wherein, The method further includes: ii-1 Reduce the second SOC threshold and the third SOC threshold by the third reduction rate respectively to obtain the updated second SOC threshold and the updated third SOC threshold; iii-1 The electrochemical device is subjected to a third charge-discharge cycle with the charging current; iv-1 In response to the completion of the third charge-discharge cycle of the electrochemical device, the electrochemical device is subjected to intermittent charging operation again. During the intermittent charging operation, data related to the electrochemical device is acquired. Based on the data related to the electrochemical device, the lithium plating SOC of the electrochemical device is determined, and the relationship between the lithium plating SOC and the updated second SOC threshold and the updated third SOC threshold is determined. v-1 When the lithium plating SOC is greater than the updated third SOC threshold and less than the updated second SOC threshold, repeat steps i-1 to iii-1 until the difference between the current charging voltage and the initial charging voltage of the electrochemical device is greater than the voltage difference threshold, and generate a prompt message.

6. The electrochemical device management method according to claim 4, wherein, The method further includes: ii-2 In response to the completion of the third charge-discharge cycle of the electrochemical device, the electrochemical device is subjected to intermittent charging operation again. During the intermittent charging operation, data related to the electrochemical device is acquired. Based on the data related to the electrochemical device, the lithium plating SOC of the electrochemical device is determined, and the relationship between the lithium plating SOC and the second SOC threshold and the third SOC threshold is determined. iii-2 When the lithium plating SOC is greater than the third SOC threshold and less than the second SOC threshold, repeat steps i-2 to ii-2 until the difference between the current charging current and the initial charging current of the electrochemical device is greater than the current difference threshold, and generate a prompt message.

7. The electrochemical device management method according to claim 1, wherein, Heating elements are provided inside the electrochemical device and / or on the outer surface of the electrochemical device.

8. The electrochemical device management method according to claim 7, wherein, The heating element is made of at least one of nickel, nickel-aluminum alloy, copper, polyimide, and silicone; the impedance of the heating element ranges from 0.01Ω to 50Ω.

9. The electrochemical device management method according to claim 7, wherein, The heating element is made of a material with a positive temperature coefficient; the impedance of the heating element ranges from 0.01Ω to 50Ω.

10. The electrochemical device management method according to claim 1, wherein, The data related to the electrochemical device includes the state of charge (SOC) and internal resistance of the electrochemical device. The intermittent charging operation includes multiple charging periods and multiple interruptions. The step of acquiring the data related to the electrochemical device during the intermittent charging operation and determining the lithium plating SOC of the electrochemical device based on the data related to the electrochemical device includes: During the intermittent charging operation, for each of the plurality of intermittent periods, the SOC and internal resistance of the electrochemical device during the intermittent period are obtained. Based on the plurality of SOCs of the electrochemical device and the plurality of internal resistances of the electrochemical device corresponding to the plurality of SOCs, a first curve is obtained. The first curve is a mapping curve corresponding to the SOC and internal resistance of the electrochemical device. Based on the first curve, the state of lithium deposition (SOC) of the electrochemical device is determined.

11. The electrochemical device management method according to claim 10, wherein, The step of determining the lithium plating state of the electrochemical device based on the first curve includes at least one of method 1 or method 2, wherein: Method 1 includes: Taking the first derivative of the first curve yields the second curve; and The SOC corresponding to the first point on the second curve with a negative slope is determined as the SOC for lithium plating. Method 2 includes: The second curve is obtained by taking the first derivative of the first curve; Taking the second derivative of the second curve yields the third curve; and The SOC corresponding to the point where the ordinate of the third curve first appears to be less than zero is determined as the lithium plating SOC.

12. The electrochemical device management method according to claim 1, wherein, The intermittent charging operation includes multiple charging cycles, each charging cycle including a charging period and an intermittent period, during which the SOC of the electrochemical device increases by a unit magnitude.

13. The electrochemical device management method according to claim 12, wherein, The electrochemical device includes at least one of a lithium iron phosphate system electrochemical device, a nickel-cobalt-manganese oxide system electrochemical device, or a lithium cobalt oxide system electrochemical device, wherein... The electrochemical device is a lithium iron phosphate system electrochemical device, the unit amplitude ranges from 0.5% to 10%, and the duration of the intermittent period ranges from 1 second to 15 seconds; The electrochemical device is a lithium nickel cobalt manganese oxide system electrochemical device, the unit amplitude ranges from 0.5% to 10%, and the duration of the intermittent period ranges from 1 second to 30 seconds; The electrochemical device is a lithium cobalt oxide system electrochemical device, the unit amplitude ranges from 0.5% to 10%, and the duration of the intermittent period ranges from 1 second to 30 seconds.

14. The electrochemical device management method according to claim 13, wherein, The method satisfies any one of conditions a) to f): a) The electrochemical device is a lithium iron phosphate system electrochemical device, the electrochemical device is in an ambient temperature of -10℃ to 10℃, the unit amplitude ranges from 0.5% to 10%, and the duration of the intermittent period ranges from 5 seconds to 15 seconds; b) The electrochemical device is a lithium iron phosphate system electrochemical device, the electrochemical device is in an ambient temperature of 10°C to 45°C, the unit amplitude ranges from 0.5% to 10%, and the duration of the intermittent period ranges from 1 second to 10 seconds; c) The electrochemical device is a lithium nickel cobalt manganese oxide system electrochemical device, the electrochemical device is in an ambient temperature of -10℃ to 10℃, the unit amplitude ranges from 0.5% to 10%, and the duration of the intermittent period ranges from 10 seconds to 30 seconds; d) The electrochemical device is a lithium nickel cobalt manganese oxide system electrochemical device, the electrochemical device is in an ambient temperature of 10°C to 45°C, the unit amplitude ranges from 0.5% to 10%, and the duration of the intermittent period ranges from 1 second to 10 seconds; e) The electrochemical device is a lithium cobalt oxide system electrochemical device, the electrochemical device is in an ambient temperature of -10°C to 10°C, the unit amplitude ranges from 0.5% to 10%, and the duration of the intermittent period ranges from 15 seconds to 30 seconds; f) The electrochemical device is a lithium cobalt oxide system electrochemical device, the electrochemical device is in an ambient temperature of 10°C to 45°C, the unit amplitude ranges from 0.5% to 10%, and the duration of the intermittent period ranges from 1 second to 10 seconds.

15. A system comprising a processor and a machine-readable storage medium storing machine-executable instructions executable by the processor, wherein the processor, when executing the machine-executable instructions, implements the method of any one of claims 1-14.

16. A battery module comprising the system of claim 15.

17. An electronic device, wherein, The electronic device includes the battery module as described in claim 16.

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