Battery cycle life prediction method and device, storage medium and electronic equipment

Abstract

The application discloses a battery cycle life prediction method and device, a storage medium and electronic equipment, which can perform a first battery cycle on a pre-lithiated battery, and obtain a corresponding first theoretical reaction potential; perform N times of the battery cycle on the pre-lithiated battery, and obtain a corresponding second theoretical reaction potential when the Nth battery cycle is performed, wherein the Nth battery cycle is counted from the first battery cycle; perform a first battery cycle on a non-pre-lithiated battery, and obtain a corresponding third theoretical reaction potential, wherein the non-pre-lithiated battery has never been subjected to a battery cycle before the first battery cycle; and determine the battery cycle number of the pre-lithiated battery according to the first theoretical reaction potential, the second theoretical reaction potential and the third theoretical reaction potential. The application can accurately predict the battery cycle number of the battery based on the reaction potential of the battery, and the prediction result is relatively accurate and the effect is relatively good.

Description

Technical Field

[0001] This invention relates to the field of energy storage, and in particular to a method, apparatus, storage medium, and electronic device for predicting battery cycle life. Background Technology

[0002] With the booming development of the automotive and energy storage industries, the requirements for the lifespan of lithium-ion power batteries and energy storage batteries are becoming increasingly stringent. Pre-lithiation of batteries is an effective method to improve the cycle life of lithium-ion batteries, but there is still no good method for predicting the cycle number of batteries after pre-lithiation. Therefore, how to accurately predict the cycle number of batteries after pre-lithiation has become a technical problem that urgently needs to be solved by researchers in this field. Summary of the Invention

[0003] In view of the above problems, the present invention provides a battery cycle life prediction method, apparatus, storage medium and electronic device that overcomes or at least partially solves the above problems.

[0004] Firstly, a method for predicting battery cycle life includes: The pre-lithiated battery is subjected to its first cell cycle, and the corresponding first theoretical reaction potential is obtained. Prior to the first cell cycle, the pre-lithiated battery has never undergone cell cycle. The pre-lithiated battery is subjected to N cell cycles, and the second theoretical reaction potential corresponding to the Nth cell cycle is obtained, wherein the Nth cell cycle is counted from the first cell cycle. The battery without pre-lithiation is subjected to the first cell cycle, and the corresponding third theoretical reaction potential is obtained. Prior to the first cell cycle, the battery without pre-lithiation has never undergone cell cycle. The number of battery cycles for the pre-lithiated battery is determined based on the first theoretical reaction potential, the second theoretical reaction potential, and the third theoretical reaction potential.

[0005] Optionally, in some optional embodiments, the first cell cycle of the pre-lithiated battery to obtain the corresponding first theoretical reaction potential includes: The pre-lithiated battery is fully charged at a preset standard rate. After the pre-lithiated battery is fully charged, it is discharged at the preset standard rate until the voltage of the pre-lithiated battery drops to the preset cutoff voltage. When the voltage of the pre-lithiated battery drops to the preset cutoff voltage, the first theoretical reaction potential of the pre-lithiated battery is measured.

[0006] Optionally, in some optional embodiments, performing N cell cycles on the pre-lithiated battery and obtaining the second theoretical reaction potential corresponding to the Nth cell cycle includes: The pre-lithiated battery is subjected to N cell cycles, wherein each cell cycle includes: fully charging the pre-lithiated battery at the preset standard rate; and discharging the pre-lithiated battery at the preset standard rate after it is fully charged until the voltage of the pre-lithiated battery drops to the preset cutoff voltage. After the Nth cell cycle of the pre-lithiated battery, the second theoretical reaction potential of the pre-lithiated battery is measured.

[0007] Optionally, in some optional embodiments, the first cell cycle of the un-lithiated battery and the acquisition of the corresponding third theoretical reaction potential includes: The un-lithium-treated battery is fully charged at the preset standard rate. After the un-lithiated battery is fully charged, it is discharged at the preset standard rate until the voltage of the un-lithiated battery drops to the preset cutoff voltage. When the voltage of the un-lithiated battery drops to the preset cutoff voltage, the third theoretical reaction potential of the un-lithiated battery is measured.

[0008] Optionally, in some optional embodiments, determining the number of battery cycles of the pre-lithiated battery based on the first theoretical reaction potential, the second theoretical reaction potential, and the third theoretical reaction potential includes: According to Formula 1: The number of battery cycles of the pre-lithiated battery is calculated, wherein the... The number of battery cycles, the The first theoretical reaction potential, the The second theoretical reaction potential, the This is the third theoretical reaction potential.

[0009] In a second aspect, a battery cycle life prediction device includes: a first reaction potential acquisition unit, a second reaction potential acquisition unit, a third reaction potential acquisition unit, and a cycle number determination unit. The first reaction potential obtaining unit is used to perform the first cell cycle on the pre-lithiated battery and obtain the corresponding first theoretical reaction potential, wherein the pre-lithiated battery has never been cell cycled before the first cell cycle is performed on the pre-lithiated battery. The second reaction potential obtaining unit is used to perform N cell cycles on the pre-lithiated battery and obtain the second theoretical reaction potential corresponding to the Nth cell cycle, wherein the Nth cell cycle is counted from the first cell cycle. The third reaction potential acquisition unit is used to perform the first cell cycle on the un-lithiated battery and obtain the corresponding third theoretical reaction potential. Before performing the first cell cycle on the un-lithiated battery, the un-lithiated battery has never been cell cycled. The cycle number determination unit is used to determine the number of battery cycles of the pre-lithiated battery based on the first theoretical reaction potential, the second theoretical reaction potential, and the third theoretical reaction potential.

[0010] Optionally, in some alternative embodiments, the first reaction potential obtaining unit includes: a first fully charged sub-unit, a first electron discharge unit, and a first potential obtaining sub-unit; The first full-charge subunit is used to fully charge the pre-lithiated battery at a preset standard rate; The first discharge unit is used to discharge the pre-lithiated battery at the preset standard rate after the pre-lithiated battery is fully charged, until the voltage of the pre-lithiated battery drops to the preset cutoff voltage. The first potential acquisition subunit is used to measure the first theoretical reaction potential of the pre-lithiated battery when the voltage of the pre-lithiated battery drops to the preset cutoff voltage.

[0011] Optionally, in some alternative embodiments, the second reaction potential obtaining unit includes: a cell circulation subunit and a second potential obtaining subunit; The cell cycle subunit is used to perform N cell cycles on the pre-lithiated battery, wherein each cell cycle performs the following: fully charging the pre-lithiated battery at the preset standard rate; and discharging the pre-lithiated battery at the preset standard rate after the pre-lithiated battery is fully charged, until the voltage of the pre-lithiated battery drops to the preset cutoff voltage. The second potential acquisition sub-unit is used to measure the second theoretical reaction potential of the pre-lithiated battery after the Nth cell cycle of the pre-lithiated battery.

[0012] Thirdly, a computer-readable storage medium having a program stored thereon, which, when executed by a processor, implements the battery cycle life prediction method described in any of the preceding claims.

[0013] Fourthly, an electronic device includes at least one processor, at least one memory and a bus connected to the processor; wherein the processor and the memory communicate with each other via the bus; the processor is configured to call program instructions in the memory to execute the battery cycle life prediction method described in any of the preceding claims.

[0014] By employing the above technical solution, this invention provides a method for performing a first cell cycle on a pre-lithiated battery and obtaining a corresponding first theoretical reaction potential. Prior to this first cell cycle, the pre-lithiated battery has never undergone cell cycling. The pre-lithiated battery is then subjected to N cell cycles, and a second theoretical reaction potential is obtained for the Nth cell cycle, where the Nth cell cycle is counted from the first cell cycle. A non-pre-lithiated battery is then subjected to a first cell cycle, and a corresponding third theoretical reaction potential is obtained. Prior to this first cell cycle, the non-pre-lithiated battery has never undergone cell cycling. Based on the first, second, and third theoretical reaction potentials, the number of cell cycles for the pre-lithiated battery is determined. Therefore, this invention can accurately predict the number of cell cycles based on the battery's reaction potential, with relatively accurate prediction results and good performance.

[0015] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0016] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 A flowchart of a battery cycle life prediction method provided by the present invention is shown; Figure 2 This invention provides a schematic diagram of the reaction range for a pre-lithiation-fed cell cycle. Figure 3 A schematic diagram of a cell cycling process provided by the present invention is shown; Figure 4 A schematic diagram of the structure of a battery cycle life prediction device provided by the present invention is shown; Figure 5A schematic diagram of the structure of an electronic device provided by the present invention is shown. Detailed Implementation

[0017] With the booming development of the automotive and energy storage industries, the requirements for the lifespan of lithium-ion power batteries and energy storage batteries are becoming increasingly stringent. Pre-lithiation is an effective method to improve the cycle life of lithium-ion batteries, but there is still no good method for predicting the number of cycles after pre-lithiation. Pre-lithiation refers to adding lithium to the inside of the lithium-ion battery to replenish lithium ions before it is put into operation. By replenishing lithium to the electrode materials through pre-lithiation, the irreversible lithium loss caused by the formation of the SEI film is offset, thereby improving the total capacity and energy density of the battery. During the first charge of the cell, an SEI film forms on the surface of the negative electrode, consuming active lithium. Pre-lithiation replenishes the consumed active lithium, thereby improving the specific capacity and cycle performance of the cell.

[0018] When designing battery cells, factors such as process tolerance and preventing lithium deposition during charging are taken into account. Therefore, the CB value (capacity per unit area of ​​negative electrode or capacity per unit area of ​​positive electrode) of the battery cell is set to be greater than 1, usually around 1.1. Through pre-lithiation, the remaining uncharged negative electrode material can be intercalated with lithium, further increasing the active lithium storage of the negative electrode sheet.

[0019] The inventors of this solution discovered through research that: the average charging voltage of the battery cell equals the charging energy. Charging capacity; Average discharge voltage of the battery cell = Discharge energy Discharge capacity; simultaneously, the average charging voltage = theoretical reaction potential + polarization voltage, and the average discharging voltage = theoretical reaction potential - polarization voltage. Therefore, it can be deduced that the theoretical reaction potential = (average charging voltage + average discharging voltage). 2. Theoretical reaction potential = positive electrode reaction potential - negative electrode reaction potential.

[0020] In pre-lithiated cells, the loss of active lithium during cell cycling leads to a decrease in the cell's theoretical reaction potential. The specific principle is as follows: Figure 1 As shown, the average discharge voltage of a battery cell is obtained by subtracting the negative electrode reaction potential from the positive electrode reaction potential. After pre-lithiation, the potential of the active lithium participating in the reaction in the negative electrode is lower, while the positive electrode reaction potential remains unchanged, resulting in a higher theoretical reaction potential for the battery cell. However, as the battery cell continues to cycle, the active lithium is gradually consumed, and the reaction range of the active lithium participating in the reaction in the negative electrode shifts to the right to a region with a higher reaction potential, while the positive electrode reaction potential remains unchanged, thus causing a decrease in the theoretical reaction potential of the battery cell. This invention can predict the number of cycles in the horizontal segment after pre-lithiation by using the theoretical reaction potential to infer the loss of active lithium based on the relationship between the theoretical reaction potential and the loss of active lithium.

[0021] Combination Figure 1As shown in the schematic diagram, during the cell cycle, the negative electrode reaction region shifts to the right, the negative electrode reaction potential increases, and this leads to a decrease in the average discharge voltage of the cell.

[0022] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0023] like Figure 2 As shown, the present invention provides a battery cycle life prediction method, including: S100, S200, S300 and S400; S100. Perform the first cell cycle on the pre-lithiated battery and obtain the corresponding first theoretical reaction potential; Prior to the first cell cycle of the pre-lithiated battery, the pre-lithiated battery had never undergone cell cycle. Optionally, the pre-lithiated battery mentioned in S100 can be understood as a battery that has completed pre-lithiation but has not yet been charged. Therefore, in S100, the present invention can perform the first cell cycle on the battery. It should be noted that: cell cycle refers to the complete process of charging and discharging the battery.

[0024] For example, in some optional implementations, S100 includes: steps 1.1, 1.2, and 1.3; Step 1.1: Fully charge the pre-lithiated battery at a preset standard rate; Optionally, different battery cell products (batteries) have different standard rates, which can be set according to the actual product. This invention does not impose any restrictions on this. It should be noted that the standard rate used in the charging and discharging processes is the same when the battery is cycled.

[0025] Optionally, fully charging the pre-lithiated battery means fully charging the pre-lithiated battery. That is, when charging the battery, the present invention can continuously monitor the battery's state of charge to ensure that the battery is fully charged. The present invention will not describe this in detail.

[0026] Step 1.2: After the pre-lithiated battery is fully charged, discharge the pre-lithiated battery at the preset standard rate until the voltage of the pre-lithiated battery drops to the preset cutoff voltage. Optionally, different battery cell products have different cutoff voltages, which can be set according to the actual product. This invention does not impose any restrictions on this. It should be noted that during the battery discharge process, this invention can continuously monitor the battery voltage status. When the voltage drops to the preset cutoff voltage, it switches to step 1.3.

[0027] Step 1.3: When the voltage of the pre-lithiated battery drops to the preset cutoff voltage, the first theoretical reaction potential of the pre-lithiated battery is measured.

[0028] Optionally, when the voltage drops to the preset cutoff voltage, the present invention can switch to step 1.3 to directly measure the first theoretical reaction potential.

[0029] It should be noted that the first theoretical reaction potential refers to the theoretical reaction potential of the pre-lithium battery cell during its first cycle.

[0030] S200, Perform N cell cycles on the pre-lithiated battery and obtain the second theoretical reaction potential corresponding to the Nth cell cycle; The Nth cell cycle is counted starting from the first cell cycle; Optionally, as mentioned above, each cell cycle can be roughly divided into two processes: full charging at a preset standard rate and discharging at a preset standard rate. To accurately predict the active lithium loss in each cell cycle, and thus predict how many cell cycles the pre-lithiated battery can undergo, this invention can collect the corresponding second theoretical reaction potential after the battery has undergone N cell cycles.

[0031] It should be noted that this invention does not impose specific limitations on N, which can be set according to actual needs. Generally speaking, the smaller the value of N, the earlier the cycle life of the battery cell can be predicted while ensuring accuracy; the larger the value of N, the more the impact of battery cell testing errors and activation factors on battery life prediction can be reduced. The range of N values ​​can be: 50≤N≤200.

[0032] For example, in some optional implementations, S200 includes: steps 2.1 and 2.2; Step 2.1: Perform N cell cycles on the pre-lithiated battery, wherein each cell cycle includes: fully charging the pre-lithiated battery at the preset standard rate; discharging the pre-lithiated battery at the preset standard rate after it is fully charged, until the voltage of the pre-lithiated battery drops to the preset cutoff voltage. Step 2.2: After performing the Nth cell cycle on the pre-lithiated battery, the second theoretical reaction potential of the pre-lithiated battery is measured.

[0033] Optionally, the N mentioned in this invention is counted starting from the first cell cycle. For example, if N equals 100, it means that 100 cell cycles are performed on the pre-lithiated battery, including the first cell cycle and the 99 cell cycles after the first cell cycle. This invention does not limit this.

[0034] S300, Perform the first cell cycle on the un-lithiated battery and obtain the corresponding third theoretical reaction potential; Prior to the first cell cycle of the un-lithiated battery, the un-lithiated battery had never undergone cell cycle. Optionally, the non-pre-lithiated battery has the same battery parameters as the pre-lithiated battery, except that it is not pre-lithiated, such as positive electrode areal density, CB value and liquid injection coefficient.

[0035] Optionally, in some alternative implementations, step S300 includes: steps 3.1, 3.2, and 3.3; Step 3.1: Fully charge the un-pre-lithiated battery using the preset standard charging rate; Optionally, a non-pre-lithiated battery refers to a battery that has not yet undergone pre-lithiation, that is, a battery whose negative electrode material has not been lithium-intercalated. This invention does not limit this.

[0036] Optionally, the un-lithiated battery in step 3.1 is also a battery that has not been charged. In order to determine the corresponding reaction potential of the un-lithiated battery during the first cell cycle, the present invention can perform a first cell cycle on it.

[0037] Optionally, for step 3.1, please refer to step 1.1 above for the same understanding, and the present invention will not repeat it.

[0038] Step 3.2: After the un-lithiated battery is fully charged, discharge the un-lithiated battery at the preset standard rate until the voltage of the un-lithiated battery drops to the preset cutoff voltage. Optionally, for step 3.2, please refer to step 1.2 above for the same understanding, and the present invention will not elaborate on it.

[0039] Step 3.3: When the voltage of the un-lithiated battery drops to the preset cutoff voltage, the third theoretical reaction potential of the un-lithiated battery is measured.

[0040] Optionally, for step 3.3, please refer to step 1.3 above for the same understanding, and this invention will not repeat it.

[0041] S400. Determine the number of battery cycles for the pre-lithiated battery based on the first theoretical reaction potential, the second theoretical reaction potential, and the third theoretical reaction potential.

[0042] Optionally, the battery cycle count mentioned in this invention can be understood as the theoretical battery cycle life. That is, how many times the battery can be charged and discharged; this invention does not limit this.

[0043] Optionally, the present invention does not impose specific limitations on the process of determining the number of battery cycles, and can set it according to actual needs.

[0044] For example, in some alternative implementations, S400 includes: According to Formula 1: The number of battery cycles of the pre-lithiated battery is calculated, wherein the... The number of battery cycles, the The first theoretical reaction potential, the The second theoretical reaction potential, the This is the third theoretical reaction potential.

[0045] It should be noted that the battery cycle count calculated based on Formula 1 above can be understood as the predicted cycle life in the horizontal segment. The cell cycling process can be divided into horizontal and inclined segments; please refer to [link to relevant documentation] for details. Figure 3 To understand.

[0046] Optionally, to further clarify the present invention, specific examples are provided below to illustrate the solution and effects of the present invention.

[0047] The pre-lithiation method in this embodiment is lithium powder pre-lithiation, but this invention is not limited to lithium powder pre-lithiation. The standard charge / discharge process for both system embodiments is as follows: 1. Standard charging: 25 degrees Celsius, 1 / 3C charging to the upper limit voltage (e.g., the voltage corresponding to 100% charge); 2. Standard discharging: 25 degrees Celsius, 1 / 3C discharging to the lower limit voltage (preset cutoff voltage). The upper and lower limit voltage ranges for lithium iron phosphate cells are 2.5-3.65V; the upper and lower limit voltage ranges for ternary lithium cells are 2.5-4.25V. It should be noted that "C" here refers to nominal capacity, and "V" is the voltage unit: volts.

[0048] Taking lithium iron phosphate lithium-ion cells as an example, the pre-lithiation method can be one or more of the following: positive electrode pre-lithiation, negative electrode pre-lithiation, electrochemical pre-lithiation, and chemical pre-lithiation; the pre-lithiation method in the following embodiment is lithium powder pre-lithiation. Lithium powder pre-lithiation is carried out by roller coating. The coated negative electrode sheet is coated with lithium powder on the surface of the negative electrode through a secondary roller coating.

[0049] As shown in Table 1, the specific parameters for Examples 1-4 are as follows: The cathode material is lithium iron phosphate (LPF), and the cathode formulation is lithium iron phosphate:SP:PVDF = 97%:1%:2%; The negative electrode material is graphite, and the formulation of this example is graphite:SP:CMC:SBR:96.7%:1%:0.8%:1.5%; The cell's CB value is 1.12; The electrolyte used is commercially available lithium iron phosphate electrolyte; The diaphragm is made of PP and is 14 micrometers thick.

[0050] As shown in Table 1, the specific parameters for Examples 5-9 are as follows: The pre-lithiation method is lithium powder pre-lithiation; The positive electrode material uses NCM, with the following formula: NCM811:SP:CNTs:PVDF=97.8%:0.8%:0.5%:0.9%; The negative electrode material is a graphite and silicon oxide composite material, with a main material ratio of graphite:silicon = 8:2; the electrode formulation is: main material:SP:CNTS:PAA:SBR = 95%:1.5%:0.1%:1.1%:2.2%; The cell's CB value is 1.08; The electrolyte used is a commercially available electrolyte suitable for high-nickel silicon-carbon materials; The diaphragm is made of PE and has a thickness of 9 micrometers.

[0051] The cell cycling process in all embodiments includes: Charging: 1C constant current and constant voltage charging to the upper limit voltage, cut-off current 0.05C; Discharge: 1C constant current discharge to the lower limit voltage (preset cutoff voltage).

[0052] Table 1 below compares the cycle life of different pre-lithiation amounts.

[0053] Table 1

[0054] As shown in Table 1 above, different pre-lithiation levels will affect both the predicted and actual lifespan of the battery. This invention can determine the pre-lithiation levels for different cell products through continuous testing and experimentation, ensuring the accuracy of the prediction results. Furthermore, this invention can achieve rapid prediction results in a short period by reducing the number of cycles N, resulting in a faster response.

[0055] like Figure 4As shown, the present invention provides a battery cycle life prediction device, including: a first reaction potential acquisition unit 100, a second reaction potential acquisition unit 200, a third reaction potential acquisition unit 300, and a cycle number determination unit 400; The first reaction potential obtaining unit 100 is used to perform the first cell cycle on the pre-lithiated battery and obtain the corresponding first theoretical reaction potential, wherein the pre-lithiated battery has never been cell cycled before the first cell cycle is performed on the pre-lithiated battery. The second reaction potential obtaining unit 200 is used to perform N cell cycles on the pre-lithiated battery and obtain the second theoretical reaction potential corresponding to the Nth cell cycle, wherein the Nth cell cycle is counted from the first cell cycle. The third reaction potential obtaining unit 300 is used to perform the first cell cycle on the un-lithiated battery and obtain the corresponding third theoretical reaction potential. Before performing the first cell cycle on the un-lithiated battery, the un-lithiated battery has never been cell cycled. The cycle number determination unit 400 is used to determine the number of battery cycles of the pre-lithiated battery based on the first theoretical reaction potential, the second theoretical reaction potential, and the third theoretical reaction potential.

[0056] Optionally, in some alternative embodiments, the first reaction potential obtaining unit 100 includes: a first fully charged sub-unit, a first electron discharge unit, and a first potential obtaining sub-unit; The first full-charge subunit is used to fully charge the pre-lithiated battery at a preset standard rate; The first discharge unit is used to discharge the pre-lithiated battery at the preset standard rate after the pre-lithiated battery is fully charged, until the voltage of the pre-lithiated battery drops to the preset cutoff voltage. The first potential acquisition subunit is used to measure the first theoretical reaction potential of the pre-lithiated battery when the voltage of the pre-lithiated battery drops to the preset cutoff voltage.

[0057] Optionally, in some alternative embodiments, the second reaction potential obtaining unit 200 includes: a cell circulation subunit and a second potential obtaining subunit; The cell cycle subunit is used to perform N cell cycles on the pre-lithiated battery, wherein each cell cycle performs the following: fully charging the pre-lithiated battery at the preset standard rate; and discharging the pre-lithiated battery at the preset standard rate after the pre-lithiated battery is fully charged, until the voltage of the pre-lithiated battery drops to the preset cutoff voltage. The second potential acquisition sub-unit is used to measure the second theoretical reaction potential of the pre-lithiated battery after the Nth cell cycle of the pre-lithiated battery.

[0058] Optionally, in some alternative embodiments, the third reaction potential obtaining unit 300 includes: a second saturated subunit, a second electron discharge unit, and a third potential obtaining subunit; The second full-charge sub-unit is used to fully charge the un-pre-lithiated battery at the preset standard rate; The second discharge unit is used to discharge the un-lithiated battery at the preset standard rate after the un-lithiated battery is fully charged, until the voltage of the un-lithiated battery drops to the preset cutoff voltage. The third potential acquisition subunit is used to measure the third theoretical reaction potential of the un-lithiated battery when the voltage of the un-lithiated battery drops to the preset cutoff voltage.

[0059] Optionally, in some alternative embodiments, the loop count determination unit 400 includes: a loop count determination subunit; The cycle number determination sub-unit is used according to Formula 1: The number of battery cycles of the pre-lithiated battery is calculated, wherein the... The number of battery cycles, the The first theoretical reaction potential, the The second theoretical reaction potential, the This is the third theoretical reaction potential.

[0060] The present invention provides a computer-readable storage medium having a program stored thereon, which, when executed by a processor, implements the battery cycle life prediction method described in any of the preceding claims.

[0061] like Figure 5 As shown, the present invention provides an electronic device 70, which includes at least one processor 701, at least one memory 702 and a bus 703 connected to the processor 701; wherein the processor 701 and the memory 702 communicate with each other through the bus 703; the processor 701 is used to call program instructions in the memory 702 to execute the battery cycle life prediction method described above.

[0062] In this invention, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, without necessarily requiring or implying 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 a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0063] 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.

[0064] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined in this invention may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0065] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A method for predicting battery cycle life, characterized in that, include: The pre-lithiated battery is subjected to its first cell cycle, and the corresponding first theoretical reaction potential is obtained. Before the first cell cycle, the pre-lithiated battery has never undergone cell cycle. The theoretical reaction potential = (average charging voltage + average discharging voltage) ÷ 2. The pre-lithiated battery is subjected to N cell cycles, and the second theoretical reaction potential corresponding to the Nth cell cycle is obtained, wherein the Nth cell cycle is counted from the first cell cycle. The battery without pre-lithiation is subjected to the first cell cycle, and the corresponding third theoretical reaction potential is obtained. Prior to the first cell cycle, the battery without pre-lithiation has never undergone cell cycle. The number of battery cycles for the pre-lithiated battery is determined based on the first theoretical reaction potential, the second theoretical reaction potential, and the third theoretical reaction potential, including: according to Formula 1: The number of battery cycles of the pre-lithiated battery is calculated, wherein the... The number of battery cycles, the The first theoretical reaction potential, the The second theoretical reaction potential, the This is the third theoretical reaction potential.

2. The method according to claim 1, characterized in that, The process of performing the first cell cycle on the pre-lithiated battery and obtaining the corresponding first theoretical reaction potential includes: The pre-lithiated battery is fully charged at a preset standard rate. After the pre-lithiated battery is fully charged, it is discharged at the preset standard rate until the voltage of the pre-lithiated battery drops to the preset cutoff voltage. When the voltage of the pre-lithiated battery drops to the preset cutoff voltage, the first theoretical reaction potential of the pre-lithiated battery is measured.

3. The method according to claim 2, characterized in that, The step of performing N cell cycles on the pre-lithiated battery and obtaining the second theoretical reaction potential corresponding to the Nth cell cycle includes: The pre-lithiated battery is subjected to N cell cycles, wherein each cell cycle includes: fully charging the pre-lithiated battery at the preset standard rate; and discharging the pre-lithiated battery at the preset standard rate after it is fully charged until the voltage of the pre-lithiated battery drops to the preset cutoff voltage. After the Nth cell cycle of the pre-lithiated battery, the second theoretical reaction potential of the pre-lithiated battery is measured.

4. The method according to claim 3, characterized in that, The process of performing the first cell cycle on the un-lithiated battery and obtaining the corresponding third theoretical reaction potential includes: The un-lithium-treated battery is fully charged at the preset standard rate. After the un-lithiated battery is fully charged, it is discharged at the preset standard rate until the voltage of the un-lithiated battery drops to the preset cutoff voltage. When the voltage of the un-lithiated battery drops to the preset cutoff voltage, the third theoretical reaction potential of the un-lithiated battery is measured.

5. A battery cycle life prediction device, characterized in that, include: The system comprises a first reaction potential acquisition unit, a second reaction potential acquisition unit, a third reaction potential acquisition unit, and a cycle number determination unit. The first reaction potential acquisition unit is used to perform the first cell cycle on the pre-lithiated battery and obtain the corresponding first theoretical reaction potential. Before performing the first cell cycle on the pre-lithiated battery, the pre-lithiated battery has never performed a cell cycle. The theoretical reaction potential = (average charging voltage + average discharging voltage) ÷ 2. The second reaction potential obtaining unit is used to perform N cell cycles on the pre-lithiated battery and obtain the second theoretical reaction potential corresponding to the Nth cell cycle, wherein the Nth cell cycle is counted from the first cell cycle. The third reaction potential acquisition unit is used to perform the first cell cycle on the un-lithiated battery and obtain the corresponding third theoretical reaction potential. Before performing the first cell cycle on the un-lithiated battery, the un-lithiated battery has never been cell cycled. The cycle number determination unit is used to determine the number of battery cycles of the pre-lithiated battery based on the first theoretical reaction potential, the second theoretical reaction potential, and the third theoretical reaction potential, wherein the determination includes: according to Formula 1: The number of battery cycles of the pre-lithiated battery is calculated, wherein the... The number of battery cycles, the The first theoretical reaction potential, the The second theoretical reaction potential, the This is the third theoretical reaction potential.

6. The apparatus according to claim 5, characterized in that, The first reaction potential acquisition unit includes: a first fully charged sub-unit, a first electron discharge unit, and a first potential acquisition sub-unit; The first full-charge subunit is used to fully charge the pre-lithiated battery at a preset standard rate; The first discharge unit is used to discharge the pre-lithiated battery at the preset standard rate after the pre-lithiated battery is fully charged, until the voltage of the pre-lithiated battery drops to the preset cutoff voltage. The first potential acquisition subunit is used to measure the first theoretical reaction potential of the pre-lithiated battery when the voltage of the pre-lithiated battery drops to the preset cutoff voltage.

7. The apparatus according to claim 6, characterized in that, The second reaction potential acquisition unit includes: a cell circulation subunit and a second potential acquisition subunit; The cell cycle subunit is used to perform N cell cycles on the pre-lithiated battery, wherein each cell cycle performs the following: fully charging the pre-lithiated battery at the preset standard rate; and discharging the pre-lithiated battery at the preset standard rate after the pre-lithiated battery is fully charged, until the voltage of the pre-lithiated battery drops to the preset cutoff voltage. The second potential acquisition sub-unit is used to measure the second theoretical reaction potential of the pre-lithiated battery after the Nth cell cycle of the pre-lithiated battery.

8. A computer-readable storage medium having a program stored thereon, characterized in that, When the program is executed by the processor, it implements the battery cycle life prediction method as described in any one of claims 1 to 4.

9. An electronic device, characterized in that, The electronic device includes at least one processor, and at least one memory and bus connected to the processor; wherein the processor and the memory communicate with each other through the bus; the processor is used to call program instructions in the memory to execute the battery cycle life prediction method as described in any one of claims 1 to 4.

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