Lithium ion battery lithium precipitation repair method and device, electronic equipment and storage medium

Abstract

The invention discloses a lithium ion battery lithium precipitation repair method and device, electronic equipment and a storage medium. The lithium ion battery lithium precipitation repair method comprises the following steps: under the condition that lithium precipitation detection equipment connected with a lithium ion battery sends out lithium precipitation information, obtaining current time and sending time of the lithium precipitation information; calculating interval duration according to the current time and the sending time; when the interval duration is less than or equal to the first preset duration, cutting off the charging current of the lithium ion battery, and standing the lithium ion battery for a second preset duration; and under the condition that the interval duration is larger than the first preset duration, the lithium ion battery is controlled to discharge at the rate within the preset rate range, and the rate within the preset rate range is larger than the rated charging rate of the lithium ion battery. According to the embodiment of the invention, precipitated lithium is effectively repaired, and the service life of the lithium ion battery is prolonged.

Description

Technical Field

[0001] The present application belongs to the field of battery technology, and specifically relates to a lithium-ion battery lithium deposition repair method, device, electronic equipment and storage medium. Background Art

[0002] With the development of battery technology, users have higher and higher requirements for battery performance. For example, for the currently more commonly used lithium-ion batteries, users may require them to have high charging efficiency and high power capacity.

[0003] During the charging process of lithium-ion batteries, the accumulation of lithium ions on the surface of graphite as the negative electrode does not match the transfer between graphite sheets, causing lithium ions to be deposited on the surface of graphite particles with a high degree of lithium insertion in the form of lithium dendrites. In the early stage of lithium precipitation, there is less metallic lithium on the graphite surface and it maintains good electrical contact with the electrode. In this case, metallic lithium, graphite and the surrounding electrolyte environment constitute the primary battery, and metallic lithium dissolves Li + , and then re-embedded into the graphite sheets with vacancies. However, during the discharge process, the precipitated lithium dendrites are first pulled out, separated from the current collector, lose electrochemical activity, and form "dead" lithium. The accumulation of "dead" lithium at the interface will not only cause capacity loss, but also hinder lithium ion transmission, increase polarization, and cause lithium-ion battery failure. Summary of the invention

[0004] The present application aims to provide a lithium ion battery lithium plating repair method, device, electronic device and storage medium, at least to solve the technical problem in the related art that lithium ion batteries are prone to lithium plating, resulting in lithium ion battery capacity loss and failure.

[0005] In order to solve the above technical problems, this application is implemented as follows:

[0006] In a first aspect, the present application provides a method for repairing lithium-ion batteries after lithium deposition, comprising:

[0007] When a lithium deposition detection device connected to a lithium-ion battery sends out lithium deposition information, obtaining the current time and the time when the lithium deposition information was sent out;

[0008] Calculate the interval duration based on the current time and the sending time;

[0009] When the interval duration is less than or equal to the first preset duration, cutting off the charging current of the lithium-ion battery and leaving the lithium-ion battery at rest for a second preset duration;

[0010] When the interval duration is greater than the first preset duration, the lithium-ion battery is controlled to discharge at a rate within a preset rate range, and the rate within the preset rate range is greater than the rated charging rate of the lithium-ion battery.

[0011] In one embodiment, when the interval duration is greater than the first preset duration, controlling the lithium-ion battery to discharge at a rate within a preset rate range includes:

[0012] When the interval duration is greater than the first preset duration and the remaining power of the lithium-ion battery is greater than or equal to the preset power, the lithium-ion battery is controlled to discharge at a rate within a preset rate range until the discharge capacity of the lithium-ion battery is equal to a times the remaining power, where a is [0.7 to 0.9].

[0013] In one embodiment, when the interval duration is greater than the first preset duration, controlling the lithium-ion battery to discharge at a rate within a preset rate range includes:

[0014] When the interval duration is greater than the first preset duration and the remaining power of the lithium-ion battery is less than the preset power, the steps of cutting off the charging current of the lithium-ion battery, leaving the lithium-ion battery to stand for a third preset duration, and controlling the lithium-ion battery to discharge at a rate within a preset rate range for a fourth preset duration are performed alternately until the discharge depth of the lithium-ion battery reaches a first preset value, and the first preset value is less than 5%.

[0015] In one embodiment, the preset rate range is [1.5*C~10*C], where C is the rated charging rate of the lithium-ion battery.

[0016] In one embodiment, when the interval duration is greater than the first preset duration, controlling the lithium-ion battery to discharge at a rate within a preset rate range includes:

[0017] When the interval time is longer than the first preset time, controlling the lithium-ion battery to discharge at the first rate for a fifth preset time;

[0018] The lithium-ion battery is controlled to discharge at a second rate for a sixth preset time, the preset rate range includes a first rate and a second rate, the first rate is greater than the second rate, the fifth preset time is less than the sixth preset time, and the second preset time is the sum of the fifth preset time and the sixth preset time.

[0019] In one embodiment, when the interval time is less than or equal to the first preset time, cutting off the charging current of the lithium-ion battery and leaving the lithium-ion battery to stand for a second preset time includes:

[0020] When the interval time is less than or equal to the first preset time and the first operation is not performed on the lithium ion, the charging current of the lithium ion battery is cut off and the lithium ion battery is left to stand for a second preset time;

[0021] Lithium-ion battery lithium plating repair methods also include:

[0022] When the interval duration is less than or equal to the first preset duration and the first operation is performed on the lithium ion, the lithium ion battery is controlled to discharge at a rate within a preset rate range, and the rate within the preset rate range is greater than the rated charge rate of the lithium ion battery;

[0023] The first operation includes at least one of the following:

[0024] 1) Charging the lithium-ion battery;

[0025] 2) Control the lithium-ion battery to discharge at a rated rate;

[0026] 3) Mobile lithium-ion battery.

[0027] In one embodiment, the first preset time length is 1 hour to 10 hours, and the second preset time length is 1 hour to 10 hours.

[0028] In a second aspect, the present application embodiment provides a lithium ion battery lithium deposition repair device, comprising:

[0029] A first acquisition module is used to acquire the current time and the time when the lithium deposition information is sent when the lithium deposition detection device connected to the lithium-ion battery sends the lithium deposition information;

[0030] A calculation module, used to calculate the interval duration according to the current time and the sending time;

[0031] A first repair module, configured to cut off the charging current of the lithium-ion battery and place the lithium-ion battery in a static state for a second preset time period when the interval time period is less than or equal to the first preset time period;

[0032] The second repair module is used to control the lithium-ion battery to discharge at a rate within a preset rate range when the interval duration is greater than the first preset duration, and the rate within the preset rate range is greater than the rated charging rate of the lithium-ion battery.

[0033] In a third aspect, an embodiment of the present application proposes an electronic device, comprising: a processor and a memory storing computer program instructions; when the processor executes the computer program instructions, it implements the method in the first aspect or any possible implementation of the first aspect.

[0034] In a fourth aspect, an embodiment of the present application proposes a computer-readable storage medium, on which computer program instructions are stored. When the computer program instructions are executed by a processor, the method in the first aspect or any possible implementation of the first aspect is implemented.

[0035] In a fifth aspect, an embodiment of the present application provides a computer program product. When instructions in the computer program product are executed by a processor of an electronic device, the electronic device executes a method in the first aspect or any possible implementation of the first aspect.

[0036] In the lithium-ion battery lithium deposition repair method, device, electronic device and storage medium provided in the embodiments of the present application, by obtaining the current time and the issuance time of the lithium deposition information, and calculating the interval duration according to the current time and the issuance time, different steps can be selected according to the interval duration to achieve lithium deposition repair; by cutting off the charging current of the lithium-ion battery when the interval duration is less than or equal to the first preset duration, and leaving the lithium-ion battery stationary for a second preset duration, so that the concentration gradient of the diffusion of lithium ions in the negative electrode sheet is reduced, and the precipitated metallic lithium returns to the negative electrode sheet, thereby achieving the repair of lithium deposition in the lithium-ion battery; by controlling the lithium-ion battery to discharge at a rate within a preset rate range when the interval duration is greater than the first preset duration, so that the dead lithium moves toward the negative electrode sheet under the action of the interface electric field, and the lithium ions have the opportunity to be re-embedded in the negative electrode sheet, thereby achieving the repair of lithium deposition in the lithium-ion battery.

[0037] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0039] Figure 1 A schematic diagram of a process for repairing a lithium-ion battery by lithium deposition provided in one embodiment of the present application;

[0040] Figure 2 A schematic diagram of the structure of a lithium ion battery lithium deposition repair device provided in one embodiment of the present application;

[0041] Figure 3 A schematic diagram of the hardware structure of an electronic device provided in one embodiment of the present application;

[0042] Figure 4 A graph of rest time and recovered capacity provided in one embodiment of the present application;

[0043] Figure 5 A curve diagram of discharge rate and cycle life provided in an embodiment of the present application;

[0044] Figure 6 A graph showing the number of cycles and cycle life provided in one embodiment of the present application. DETAILED DESCRIPTION

[0045] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only configured to explain the present application and are not configured to limit the present application. For those skilled in the art, the present application can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present application by illustrating the examples of the present application.

[0046] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "include..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0047] During the charging process of lithium-ion batteries, the accumulation of lithium ions on the surface of the negative electrode does not match the transfer of lithium ions inside the negative electrode, causing lithium ions to be deposited on the surface of the negative electrode with a higher degree of lithium insertion in the form of lithium dendrites. During the discharge process of lithium-ion batteries, the precipitated lithium dendrites are preferentially pulled out, separated from the current collector, lose electrochemical activity, and form "dead" lithium. The accumulation of "dead" lithium at the interface will not only cause battery capacity loss, but also hinder lithium ion transmission, increase polarization, and cause lithium-ion battery failure.

[0048] To solve the above problems, the present application provides a lithium ion battery lithium plating repair method, comprising:

[0049] S110, when a lithium deposition detection device connected to the lithium-ion battery sends out lithium deposition information, obtaining the current time and the time when the lithium deposition information was sent out;

[0050] The lithium-ion battery used in this application may include a positive electrode plate, a negative electrode plate, an electrolyte and a diaphragm. The positive electrode plate may be made of lithium-containing materials such as lithium iron phosphate (LiFePO4), lithium cobalt oxide (LiMn2O4), lithium manganese oxide (LiCoO2), and lithium nickel oxide (LiNiO2); the negative electrode plate may be made of carbon materials, silicon materials, and metal oxide materials, etc. The carbon material may be artificial graphite, mesophase carbon microspheres, hard carbon, etc.; the electrolyte is a lithium salt solution. In addition, the lithium-ion battery may also include a shell, the positive and negative electrode plate lead terminals of the battery, and other parts. The shell may be a steel shell, an aluminum shell, a nickel-plated iron shell, or an aluminum-plastic film.

[0051] For the convenience of description, the following description is made of graphite as an example. Inside the lithium-ion battery, a charge storage system is constructed between the positive and negative electrode sheets. When the battery is charged, the lithium ions in the positive electrode sheet are released from the positive electrode sheet under the action of the electric field, and the released lithium ions then migrate through the electrolyte and are finally embedded in the negative electrode sheet, specifically in the interplanar spacing within the graphite lattice. During the discharge process, the lithium ions flow back from the negative electrode sheet to the positive electrode sheet. Lithium ions are not unlimited when embedded in the negative electrode sheet material. If the diffusion rate of lithium ions in the electrolyte exceeds the rate of embedding in graphite, more and more metallic lithium will accumulate on the graphite surface in the form of lithium dendrites, that is, lithium precipitation occurs. The growth of lithium dendrites will affect the performance of lithium-ion batteries and limit the capacity of lithium-ion batteries. In addition, it may puncture the diaphragm, causing a micro-short circuit inside the lithium-ion battery. This micro-short circuit usually causes the battery temperature to rise rapidly. At high temperatures, the separator may melt, shrink or break, causing the lithium-ion battery to short-circuit, leading to safety issues such as fire or explosion.

[0052] The lithium deposition detection equipment is used to detect whether lithium deposition occurs in lithium-ion batteries. The lithium deposition detection equipment can use lithium metal as a reference electrode and identify the occurrence of lithium deposition by collecting the voltage and impedance of the lithium-ion battery. The lithium deposition detection equipment can also perform single-frequency impedance testing by applying a sinusoidal alternating current of a specific frequency and a specific amplitude to the constant current charge and discharge current of the lithium-ion battery to achieve real-time, in-situ, and non-destructive lithium deposition detection. This application does not limit the method used by the lithium deposition detection equipment to detect whether lithium deposition occurs in a lithium-ion battery.

[0053] Exemplarily, the lithium deposition detection device is electrically connected to a lithium-ion battery in a charging state, obtains electrical parameters of the lithium-ion battery, determines whether lithium deposition occurs in the lithium-ion battery based on the electrical parameters, and emits lithium deposition information when lithium deposition occurs in the lithium-ion battery.

[0054] The lithium deposition repair method for lithium-ion batteries in the present application can be applied to a lithium deposition repair device, and the lithium deposition repair device can be distributed in the lithium-ion battery and the lithium deposition detection device, and electrically connected and communicatively connected. The lithium deposition detection device can send the generated lithium deposition information to the lithium deposition repair device, so that the lithium deposition repair device can obtain the lithium deposition information. The lithium deposition detection device can also send the generated lithium deposition information to the lithium-ion battery, and the lithium-ion battery sends the lithium deposition information to the lithium deposition repair device when establishing a communication connection with the lithium deposition repair device. It is also possible that after the user observes that the lithium deposition detection device sends the lithium deposition information, the user imports the lithium deposition information sent by the lithium deposition detection device into the lithium deposition repair device.

[0055] When the lithium deposition detection device sends out the lithium deposition information, it can also associate the time when the lithium deposition information is sent out with the lithium deposition information, so that the user, the lithium-ion battery or the lithium deposition repair device knows the initial time when the lithium deposition phenomenon occurs.

[0056] S120, calculating the interval duration according to the current time and the sending time;

[0057] The interval duration is the difference between the current time and the issuance time. When the current time is the same as the issuance time, the interval duration is 0, that is, when lithium deposition occurs in the lithium-ion battery, the lithium-ion battery is immediately repaired for lithium deposition. When there is a difference between the current time and the issuance time, the interval duration is a positive number, that is, after lithium deposition occurs in the lithium-ion battery, the lithium-ion battery is repaired for lithium deposition at an interval of the interval duration.

[0058] S130, when the interval duration is less than or equal to the first preset duration, cutting off the charging current of the lithium-ion battery and leaving the lithium-ion battery at rest for a second preset duration;

[0059] S140, when the interval time is longer than the first preset time, controlling the lithium-ion battery to discharge at a rate within a preset rate range, wherein the rate within the preset rate range is greater than a rated charge rate of the lithium-ion battery.

[0060] The first preset time length is the time length pre-set by a person skilled in the art. When the interval time length is less than or equal to the first preset time length, it indicates that the lithium deposition phenomenon of the lithium-ion battery occurs for a short time, and the lithium deposition can be repaired by cutting off the charging current of the lithium-ion battery and leaving the lithium-ion battery to stand for a second preset time length. The occurrence of lithium deposition is due to the mismatch between the embedding of lithium ions and the diffusion to the surface of the electrode during the lithium embedding process of the negative electrode plate. The diffusion process is faster than the lithium embedding process, and the lithium ions that have not diffused into the negative electrode plate in time are precipitated on the surface of the electrode plate in the form of metallic lithium. In the early stage of lithium deposition, less metallic lithium is deposited on the negative electrode plate and all maintain good electrical contact with the negative electrode plate. Cutting off the charging current of the lithium-ion battery and leaving the lithium-ion battery to stand for a second preset time length can stop the diffusion of lithium ions to the surface of the electrode plate, and the precipitated metallic lithium no longer grows; the metallic lithium, the negative electrode plate and the surrounding electrolyte environment constitute a primary battery, and the concentration gradient of the diffusion of lithium ions in the negative electrode plate (for example: graphite sheet) is reduced, and the metallic lithium is dissolved as Li + , Li + Re-embed it into the vacant negative electrode plate to repair the lithium deposition of the lithium-ion battery.

[0061] The preset rate range is a range value pre-set by a person skilled in the art. When the interval duration is greater than the first preset time duration, it indicates that the lithium ion battery has a long lithium deposition period, and the lithium ion battery can be controlled to discharge at a rate within the preset rate range, and the rate within the preset rate range is greater than the rated charge rate of the lithium ion battery. During the interval duration, the probability that the lithium ion battery continues to charge and discharge is high, and the metallic lithium deposited on the surface of the negative electrode sheet forms dead lithium during the charging and discharging process. The lithium ion battery is controlled to discharge at a rate within the preset rate range, so that the dead lithium moves toward the negative electrode sheet under the action of the interface electric field, so that some lithium ions are re-embedded in the negative electrode sheet, thereby repairing the lithium deposition of the lithium ion battery.

[0062] The lithium deposition repair method for lithium-ion batteries provided in the embodiments of the present application obtains the current time and the time when the lithium deposition information is sent, and calculates the interval duration according to the current time and the time when the lithium deposition information is sent, so that different steps can be selected according to the interval duration to achieve lithium deposition repair; when the interval duration is less than or equal to the first preset duration, the charging current of the lithium-ion battery is cut off, and the lithium-ion battery is left to stand for a second preset duration, so that the concentration gradient of the diffusion of lithium ions in the negative electrode sheet is reduced, and the precipitated metallic lithium returns to the negative electrode sheet, thereby achieving the repair of lithium deposition in the lithium-ion battery; when the interval duration is greater than the first preset duration, the lithium-ion battery is controlled to discharge at a rate within a preset rate range, so that the dead lithium moves toward the negative electrode sheet under the action of the interface electric field, and the lithium ions have the opportunity to be re-embedded in the negative electrode sheet, thereby achieving the repair of lithium deposition in the lithium-ion battery.

[0063] In some embodiments, S140 includes:

[0064] S210, when the interval duration is greater than a first preset duration and the remaining power of the lithium-ion battery is greater than or equal to a preset power, control the lithium-ion battery to discharge at a rate within a preset rate range until the discharge depth of the lithium-ion battery reaches a first preset value, and the first preset value is less than 5%.

[0065] The depth of discharge (DoD) is the percentage of the amount of electricity released during the discharge process to the total capacity of the battery. The first preset value is preset by those skilled in the art.

[0066] Excessive discharge depth will reduce the charging efficiency and cycle efficiency of lithium-ion batteries. By limiting the discharge depth of lithium-ion batteries at a rate within a preset rate range, excessive discharge of lithium-ion batteries can be avoided.

[0067] In some embodiments, S140 further includes:

[0068] S310, when the interval time is greater than the first preset time and the remaining power of the lithium-ion battery is less than the preset power, alternately executing the steps of cutting off the charging current of the lithium-ion battery, leaving the lithium-ion battery to stand for a third preset time, and controlling the lithium-ion battery to discharge at a rate within a preset rate range for a fourth preset time, until the discharge capacity of the lithium-ion battery is equal to a times the remaining power, where a is [0.7-0.9].

[0069] The remaining power can be 95%, 90%, 85% or 80%, etc. The third preset time length and the fourth preset time length are preset values, and the third preset time length and the fourth preset time length can both be 5h. The discharge capacity of the lithium-ion battery can be the total capacity of multiple discharges at a rate within a preset rate range. Before performing alternating discharge and standing, the remaining power A of the lithium-ion battery is obtained, and in the process of controlling the lithium-ion battery to alternately discharge and stand, the discharge capacity of the lithium-ion battery reaches a*A, and the steps of alternating discharge and standing are stopped.

[0070] The remaining power of the lithium-ion battery is less than the preset power, which means that the remaining power in the lithium-ion battery is small and is not suitable for long-term rate discharge. By alternately executing the steps of cutting off the charging current of the lithium-ion battery, leaving the lithium-ion battery to rest for a third preset time, and controlling the lithium-ion battery to discharge at a rate within a preset rate range for a fourth preset time, the discharge current and voltage imbalance of the lithium-ion battery caused by rate discharge can be reduced or avoided, and lithium plating repair can be achieved through rest and rate discharge.

[0071] Exemplarily, when the interval time is greater than 10 hours and the remaining power A of the lithium-ion battery is less than 90% of the preset power, the charging current of the lithium-ion battery is first cut off, the lithium-ion battery is left to stand for 5 hours, and then the lithium-ion battery is controlled to discharge at a rate within the preset rate range for 5 hours, the charging current of the lithium-ion battery is cut off again, the lithium-ion battery is left to stand for 5 hours, and then the lithium-ion battery is controlled to discharge at a rate within the preset rate range for 5 hours, until the discharge capacity of the lithium-ion battery is equal to 0.8 times the remaining power.

[0072] In some embodiments, the preset rate range is [1.5*C~10*C], where C is the rated charging rate of the lithium-ion battery.

[0073] The rated charge rate refers to the current value required for the battery to be fully charged to the rated capacity within a specified time. The preset rate range is [1.5*C~10*C], that is, the preset rate range is 1.5 times the rated charge rate~10 times the rated charge rate, that is, the discharge rate used in S140 is greater than the rated charge rate, so as to facilitate the precipitated metal lithium to be embedded in the negative electrode sheet.

[0074] Optionally, pulse discharge or constant current discharge may be used in S140.

[0075] When performing S140, the same discharge rate may be used for discharge, or different discharge rates may be used for discharge in stages. In some embodiments, S140 includes:

[0076] S510, when the interval time is longer than the first preset time, controlling the lithium-ion battery to discharge at the first rate for a fifth preset time;

[0077] S520, controlling the lithium-ion battery to discharge at a second rate for a sixth preset time, where the preset rate range includes a first rate and a second rate, the first rate is greater than the second rate, the fifth preset time is less than the sixth preset time, and the second preset time is the sum of the fifth preset time and the sixth preset time.

[0078] The first rate, the second rate, the fifth preset duration, and the sixth preset duration are pre-set values. Optionally, the first rate is 4, the second rate is 1.5-2, the fifth preset duration is 10 seconds, and the sixth preset duration is 1 minute. Discharging at the first rate can ensure the rapid movement of metallic lithium to the negative electrode. Discharging at the second rate can alleviate the polarization caused by the high rate discharge on the one hand, and ensure the full contact between metallic lithium and the negative electrode on the other hand, and promote the recycling of metallic lithium.

[0079] In some embodiments, S130 includes:

[0080] When the interval duration is less than or equal to the first preset duration and the first operation is not performed on the lithium ion battery, cutting off the charging current of the lithium ion battery and leaving the lithium ion battery at rest for a second preset duration;

[0081] The lithium ion battery lithium deposition repair method also includes:

[0082] S610, when the interval duration is less than or equal to a first preset duration and a first operation is performed on the lithium ion battery, controlling the lithium ion battery to discharge at a rate within a preset rate range, wherein the rate within the preset rate range is greater than a rated charge rate of the lithium ion battery;

[0083] The first operation includes at least one of the following:

[0084] 1) Charging the lithium-ion battery;

[0085] 2) Control the lithium-ion battery to discharge at a rated rate;

[0086] 3) Mobile lithium-ion battery.

[0087] Within the first preset time after the lithium deposition detection device sends out the lithium deposition information, the charging current of the lithium-ion battery is immediately cut off, and the lithium-ion battery is left to stand for the second preset time, so that the lithium deposition of the lithium-ion battery is repaired. If the interval time is greater than the first preset time and S130 has been executed, S130 is continued to be executed. Within the first preset time after the lithium deposition detection device sends out the lithium deposition information, if the lithium-ion battery is not powered off and left to stand, S140 is executed. Within the first preset time after the lithium deposition detection device sends out the lithium deposition information, a first operation is performed on the lithium-ion battery, and the lithium-ion battery is controlled to discharge at a rate within a preset rate range, and the rate within the preset rate range is greater than the rated charging rate of the lithium-ion battery. The first operation includes but is not limited to: after the lithium deposition detection device sends out the lithium deposition information, the lithium-ion battery continues to be charged, after the lithium deposition detection device sends out the lithium deposition information, the lithium-ion battery is controlled to discharge at a rated rate, and after the lithium deposition detection device sends out the lithium deposition information, the lithium-ion battery is moved and shaken.

[0088] In some embodiments, the first preset time is 1 hour to 10 hours, and the second preset time is 1 hour to 10 hours. Preferably, the first preset time is 7 hours to 8 hours, so that the metallic lithium can be fully re-embedded into the negative electrode plate by diffusion.

[0089] See also Figure 2 The present application also provides a lithium ion battery lithium deposition repair device, comprising:

[0090] A first acquisition module 301 is used to acquire the current time and the time when the lithium deposition information is sent when the lithium deposition detection device connected to the lithium-ion battery sends the lithium deposition information;

[0091] A calculation module 302, used to calculate the interval duration according to the current time and the sending time;

[0092] The first repair module 303 is used to cut off the charging current of the lithium-ion battery and leave the lithium-ion battery idle for a second preset time period when the interval time period is less than or equal to the first preset time period;

[0093] The second repair module 304 is used to control the lithium-ion battery to discharge at a rate within a preset rate range when the interval time is longer than the first preset time, and the rate within the preset rate range is greater than the rated charging rate of the lithium-ion battery.

[0094] In some embodiments, the second repair module 304 includes:

[0095] The first repair unit is used to control the lithium-ion battery to discharge at a rate within a preset rate range when the interval duration is greater than a first preset duration and the remaining power of the lithium-ion battery is greater than or equal to a preset power, until the discharge depth of the lithium-ion battery reaches a first preset value, and the first preset value is less than 5%.

[0096] In some embodiments, the second repair module 304 includes:

[0097] The second repair unit is used to alternately execute the steps of cutting off the charging current of the lithium-ion battery, leaving the lithium-ion battery to stand for a third preset time, and controlling the lithium-ion battery to discharge at a rate within a preset rate range for a fourth preset time when the interval time is greater than a first preset time and the remaining power of the lithium-ion battery is less than a preset power, until the discharge depth of the lithium-ion battery reaches a first preset value, and the first preset value is less than 5%.

[0098] In some embodiments, the preset rate range is [1.5*C~10*C], where C is the rated charging rate of the lithium-ion battery.

[0099] In some embodiments, the second repair module 304 includes:

[0100] A third repair unit, configured to control the lithium-ion battery to discharge at a first rate for a fifth preset time when the interval time is longer than the first preset time;

[0101] The lithium-ion battery is controlled to discharge at a second rate for a sixth preset time, the preset rate range includes a first rate and a second rate, the first rate is greater than the second rate, the fifth preset time is less than the sixth preset time, and the second preset time is the sum of the fifth preset time and the sixth preset time.

[0102] In some embodiments, the first repair module 303 includes:

[0103] a fourth repair unit, configured to cut off the charging current of the lithium-ion battery and place the lithium-ion battery at rest for a second preset time period when the interval time period is less than or equal to the first preset time period and the first operation is not performed on the lithium ion battery;

[0104] The lithium ion battery lithium plating repair device also includes:

[0105] A third repair module 305 controls the lithium-ion battery to discharge at a rate within a preset rate range when the interval duration is less than or equal to a first preset duration and a first operation is performed on the lithium ion battery, wherein the rate within the preset rate range is greater than a rated charge rate of the lithium-ion battery;

[0106] The first operation includes at least one of the following:

[0107] 1) Charging the lithium-ion battery;

[0108] 2) Control the lithium-ion battery to discharge at a rated rate;

[0109] 3) Mobile lithium-ion battery.

[0110] In some embodiments, the first preset time length is 1 hour to 10 hours, and the second preset time length is 1 hour to 10 hours.

[0111] The lithium ion battery lithium deposition repair device provided in the embodiment of the present application performs Figure 1 The various steps in the method shown can achieve the technical effect of the lithium-ion battery lithium deposition repair method. For the sake of brevity, they will not be described in detail here.

[0112] Figure 3 A schematic diagram of the hardware structure of an electronic device provided in an embodiment of the present application is shown.

[0113] The electronic device may include a processor 401 and a memory 402 storing computer program instructions.

[0114] Specifically, the processor 401 may include a central processing unit (CPU), or an application specific integrated circuit (ASIC), or may be configured to implement one or more integrated circuits of the embodiments of the present application.

[0115] Memory 402 may include a large capacity memory for data or instructions. By way of example and not limitation, memory 402 may include a hard disk drive (HDD), a floppy disk drive, a flash memory, an optical disk, a magneto-optical disk, a magnetic tape, or a universal serial bus (USB) drive or a combination of two or more of these. In appropriate cases, memory 402 may include a removable or non-removable (or fixed) medium. In appropriate cases, memory 402 may be inside or outside of an integrated gateway disaster recovery device. In a specific embodiment, memory 402 is a non-volatile solid-state memory.

[0116] The memory may include read-only memory (ROM), random access memory (RAM), magnetic disk storage media devices, optical storage media devices, flash memory devices, electrical, optical or other physical / tangible memory storage devices. Thus, typically, the memory includes one or more tangible (non-transitory) computer-readable storage media (e.g., memory devices) encoded with software including computer-executable instructions, and when the software is executed (e.g., by one or more processors), it is operable to perform the operations described with reference to the method according to an aspect of the present disclosure.

[0117] The processor 401 reads and executes the computer program instructions stored in the memory 402 to implement any one of the lithium-ion battery lithium plating repair methods in the above embodiments.

[0118] In one example, the electronic device may further include a communication interface 403 and a bus 410. Figure 4 As shown, the processor 401, the memory 402, and the communication interface 403 are connected via a bus 410 and communicate with each other.

[0119] The communication interface 403 is mainly used to implement communication between various modules, devices, units and / or equipment in the embodiments of the present application.

[0120] Bus 410 includes hardware, software or both, and the parts of online data flow billing equipment are coupled to each other. For example, but not limitation, bus may include accelerated graphics port (AGP) or other graphics bus, enhanced industrial standard architecture (EISA) bus, front-side bus (FSB), hypertransport (HT) interconnection, industrial standard architecture (ISA) bus, infinite bandwidth interconnection, low pin count (LPC) bus, memory bus, micro channel architecture (MCA) bus, peripheral component interconnection (PCI) bus, PCI-Express (PCI-X) bus, serial advanced technology attachment (SATA) bus, video electronics standard association local (VLB) bus or other suitable bus or two or more of these combinations. In appropriate cases, bus 410 may include one or more buses. Although the present application embodiment describes and shows a specific bus, the present application considers any suitable bus or interconnection.

[0121] The electronic device can execute the lithium ion battery lithium deposition repair method in the embodiment of the present application, thereby realizing the combination Figure 1 A method for repairing lithium plating in a lithium-ion battery is described.

[0122] In addition, in combination with the lithium ion battery lithium deposition repair method in the above embodiment, the embodiment of the present application can provide a computer readable storage medium for implementation. The computer readable storage medium stores computer program instructions; when the computer program instructions are executed by the processor, any one of the lithium ion battery lithium deposition repair methods in the above embodiment is implemented.

[0123] In combination with the lithium ion battery lithium deposition repair method in the above embodiment, the present application embodiment can provide a computer program product for implementation. When the instructions in the computer program product are executed by a processor of an electronic device, any one of the lithium ion battery lithium deposition repair methods in the above embodiment is implemented.

[0124] It should be clear that the present application is not limited to the specific configuration and processing described above and shown in the figures. For the sake of simplicity, a detailed description of the known method is omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of the present application is not limited to the specific steps described and shown, and those skilled in the art can make various changes, modifications and additions, or change the order between the steps after understanding the spirit of the present application.

[0125] The functional blocks shown in the above block diagram can be implemented as hardware, software, firmware or a combination thereof. When implemented in hardware, it can be, for example, an electronic circuit, an application specific integrated circuit (ASIC), appropriate firmware, a plug-in, a function card, etc. When implemented in software, the elements of the present application are programs or code segments that are used to perform the required tasks. The program or code segment can be stored in a computer-readable storage medium, or transmitted on a transmission medium or a communication link by a data signal carried in a carrier wave. "Computer-readable storage medium" can include any medium capable of storing or transmitting information. Examples of computer-readable storage media include electronic circuits, semiconductor memory devices, ROM, flash memory, erasable ROM (EROM), floppy disks, CD-ROMs, optical disks, hard disks, optical fiber media, radio frequency (RF) links, etc. The code segment can be downloaded via a computer network such as the Internet, an intranet, etc.

[0126] It should also be noted that the exemplary embodiments mentioned in this application describe some methods or systems based on a series of steps or devices. However, this application is not limited to the order of the above steps, that is, the steps can be performed in the order mentioned in the embodiment, or in a different order from the embodiment, or several steps can be performed simultaneously.

[0127] The above are only specific implementation methods of the present application. Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, modules and units described above can refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here. It should be understood that the protection scope of the present application is not limited to this. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in this application, and these modifications or replacements should be included in the protection scope of this application.

[0128] The beneficial effects of the lithium-ion battery lithium plating repair method provided in the present application are described below through examples.

[0129] Example 1

[0130] 1. Assemble lithium-ion batteries: Use lithium iron phosphate as the positive electrode, graphite as the negative electrode, 1 mol / L lithium hexafluorophosphate as the electrolyte, ethylene carbonate and dimethyl carbonate as the solvents of the electrolyte, the volume ratio of ethylene carbonate to dimethyl carbonate is 1 / 2, polyethylene film is used as the diaphragm, and the lithium-ion batteries are assembled in a glove box filled with argon.

[0131] 2. Battery test: The assembled lithium-ion battery was activated for two cycles at a rate of 0.05C, and the cut-off voltage was set to 2.5V-3.6V, where the theoretical capacity of the graphite negative electrode was used as the rated charge and discharge rate. The constant current charging current was selected as 1C, the impedance test frequency was 15Hz, and the amplitude was 0.05mA to monitor whether lithium plating occurred in the lithium-ion battery.

[0132] 3. After the lithium deposition detection equipment sends out the lithium deposition information, the lithium-ion battery with lithium deposition phenomenon is left to stand for 1h, 2h, 3h, 4h, 5h, 6h, 7h, 8h, and 9h respectively. Figure 4 It can be seen that the capacity of the lithium-ion battery can be restored by standing still, that is, the lithium plating can be repaired. Before standing still for 7 hours, the standing time is proportional to the capacity restored by the lithium-ion battery. After standing still for 7 hours, the standing time is inversely proportional to the capacity restored by the lithium-ion battery, that is, the efficiency of restoring the capacity of the lithium-ion battery by standing still gradually decreases.

[0133] Example 2

[0134] 1. Assemble lithium-ion batteries: Use lithium iron phosphate as the positive electrode, graphite as the negative electrode, 1 mol / L lithium hexafluorophosphate as the electrolyte, ethylene carbonate and dimethyl carbonate as the solvents of the electrolyte, the volume ratio of ethylene carbonate to dimethyl carbonate is 1 / 2, polyethylene film is used as the diaphragm, and the lithium-ion batteries are assembled in a glove box filled with argon.

[0135] 2. Battery test: The assembled lithium-ion battery was activated for two cycles at a rate of 0.05C, and the cut-off voltage was set to 2.5V-3.6V, where the theoretical capacity of the graphite negative electrode was used as the rated charge and discharge rate. The constant current charging current was selected as 1C, the impedance test frequency was 15Hz, and the amplitude was 0.05mA to monitor whether lithium plating occurred in the lithium-ion battery.

[0136] 3. After the lithium deposition detection device sends out the lithium deposition information, continue charging until the first preset time of 10 hours, and set the experimental group to discharge the lithium-ion batteries with lithium deposition at 1.5C, 2C, 3C, 4C, 5C, 6C, 7C, 8C, 9C, and 10C rates for 1 minute. Figure 5 It can be seen that when the discharge rate is less than 4.5C, the discharge rate and the cycle life of the lithium-ion battery are directly proportional, and when the discharge rate is greater than 4.5C, the discharge rate and the cycle life of the lithium-ion battery are inversely proportional, that is, choosing a suitable discharge rate for the lithium-ion battery will increase the cycle life of the lithium-ion battery.

[0137] After the lithium deposition detection equipment sends out the lithium deposition information, the lithium-ion batteries in the control group are set to discharge at a rate of 1C for 1 minute, and the lithium-ion batteries in the experimental group are set to discharge at a rate of 2C for 1 minute. The cycle life of the lithium-ion batteries in the experimental and control groups is verified under the same conditions. Figure 6 , where L1 is the cycle number-cycle life curve of the lithium-ion battery in the experimental group, and L2 is the cycle number-cycle life curve of the lithium-ion battery in the control group. This shows that if lithium plating occurs in the lithium-ion battery, discharging at a 2C rate for 1 minute will be beneficial to improving the cycle life of the lithium-ion battery and restoring lithium plating.

[0138] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0139] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A lithium ion battery lithium deposition repair method, characterized in that: include: When a lithium deposition detection device connected to a lithium-ion battery sends out lithium deposition information, obtaining the current time and the time when the lithium deposition information was sent out; Calculate the interval duration according to the current time and the sending time; When the interval duration is less than or equal to the first preset duration, cutting off the charging current of the lithium-ion battery and leaving the lithium-ion battery at rest for a second preset duration; When the interval time is longer than the first preset time, the lithium-ion battery is controlled to discharge at a rate within a preset rate range, and the rate within the preset rate range is greater than the rated charging rate of the lithium-ion battery.

2. The lithium ion battery lithium plating repair method according to claim 1, characterized in that: When the interval time is longer than the first preset time, controlling the lithium-ion battery to discharge at a rate within a preset rate range includes: When the interval duration is greater than the first preset duration and the remaining power of the lithium-ion battery is greater than or equal to the preset power, the lithium-ion battery is controlled to discharge at a rate within a preset rate range until the discharge depth of the lithium-ion battery reaches a first preset value, and the first preset value is less than 5%.

3. The lithium ion battery lithium plating repair method according to claim 2, characterized in that: When the interval time is longer than the first preset time, controlling the lithium-ion battery to discharge at a rate within a preset rate range includes: When the interval time is greater than the first preset time and the remaining power of the lithium-ion battery is less than the preset power, the steps of cutting off the charging current of the lithium-ion battery, leaving the lithium-ion battery to stand for a third preset time, and controlling the lithium-ion battery to discharge at a rate within a preset rate range for a fourth preset time are performed alternately until the discharge capacity of the lithium-ion battery is equal to a times the remaining power, where a is [0.7 to 0.9].

4. The lithium ion battery lithium plating repair method according to claim 1, characterized in that: The preset rate range is [1.5*C~10*C], where C is the rated charging rate of the lithium-ion battery.

5. The lithium ion battery lithium plating repair method according to claim 1, characterized in that: When the interval time is longer than the first preset time, controlling the lithium-ion battery to discharge at a rate within a preset rate range includes: When the interval time is longer than the first preset time, controlling the lithium-ion battery to discharge at a first rate for a fifth preset time; The lithium-ion battery is controlled to discharge at a second rate for a sixth preset time, the preset rate range includes the first rate and the second rate, the first rate is greater than the second rate, the fifth preset time is less than the sixth preset time, and the second preset time is the sum of the fifth preset time and the sixth preset time.

6. The lithium ion battery lithium plating repair method according to claim 1, characterized in that: When the interval time is less than or equal to the first preset time, cutting off the charging current of the lithium-ion battery and leaving the lithium-ion battery to stand for a second preset time comprises: When the interval duration is less than or equal to the first preset duration and the first operation is not performed on the lithium ion battery, cutting off the charging current of the lithium ion battery and leaving the lithium ion battery at rest for a second preset duration; The lithium ion battery lithium deposition repair method also includes: When the interval duration is less than or equal to the first preset duration and the first operation is performed on the lithium ion battery, the lithium ion battery is controlled to discharge at a rate within a preset rate range, and the rate within the preset rate range is greater than the rated charge rate of the lithium ion battery; The first operation includes at least one of the following: 1) Charging the lithium-ion battery; 2) Control the lithium-ion battery to discharge at a rated rate; 3) Mobile lithium-ion battery.

7. The lithium ion battery lithium plating repair method according to claim 1, characterized in that: The first preset time length is 1 hour to 10 hours, and the second preset time length is 1 hour to 10 hours.

8. A lithium ion battery lithium deposition repair device, characterized in that: include: A first acquisition module is used to obtain the current time and the issuance time of the lithium deposition information when a lithium deposition detection device connected to the lithium-ion battery issues lithium deposition information; A calculation module, used to calculate the interval duration according to the current time and the sending time; A first repair module, configured to cut off the charging current of the lithium-ion battery and place the lithium-ion battery in a static state for a second preset time period when the interval time period is less than or equal to a first preset time period; The second repair module is used to control the lithium-ion battery to discharge at a rate within a preset rate range when the interval duration is greater than the first preset duration, and the rate within the preset rate range is greater than the rated charging rate of the lithium-ion battery.

9. An electronic device, characterized in that: The device comprises: a processor and a memory storing computer program instructions; when the processor executes the computer program instructions, the lithium ion battery lithium deposition repair method as described in any one of claims 1 to 7 is implemented.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer program instructions, and when the computer program instructions are executed by the processor, the lithium-ion battery lithium deposition repair method according to any one of claims 1 to 7 is implemented.

Images