A method, device, equipment and storage medium for estimating the amount of lithium in a lithium-ion battery

Abstract

The present invention discloses a method, device, equipment and storage medium for estimating the pre-lithium amount of a lithium-ion battery. The method for estimating the pre-lithium amount of a lithium-ion battery comprises: obtaining a first charging curve of a pre-lithium lithium-ion battery cell, obtaining a second charging curve of the lithium-ion battery cell; translating the first charging curve along the coordinate axis until the degree of overlap with the second charging curve reaches a set degree of overlap; obtaining the translation amount of the first charging curve, and determining the actual pre-lithium amount of the pre-lithium lithium-ion battery according to the translation amount. When the translation amount is determined by the method proposed in the present invention, and the actual pre-lithium amount is determined by the translation amount, the estimation accuracy of the actual pre-lithium amount is high. In addition, the execution time of the pre-lithium amount estimation method is short and the execution efficiency is high.

Description

Technical Field

[0001] The embodiments of the present invention relate to battery technology, and in particular to a method, device, equipment and storage medium for estimating the pre-lithium amount of a lithium-ion battery. Background Art

[0002] Lithium-ion battery negative electrode pre-lithiation technology can improve the cycle life of lithium-ion batteries and has attracted more and more attention from researchers.

[0003] At present, the common pre-lithiation method is to adhere lithium metal to a graphite negative electrode, a silicon-based negative electrode or a graphite-silicon-based negative electrode, and allow the electrolyte to infiltrate the negative electrode through a single injection. The lithium metal directly contacts the negative electrode to form a primary battery circuit inside the negative electrode. Through the potential difference between the lithium metal and the negative electrode, a portion of the active lithium ions are embedded in the negative electrode to cope with the loss of active lithium in subsequent lithium-ion battery cycles.

[0004] The conversion efficiency of lithium metal into active lithium ions is an important indicator for the design of pre-lithium treatment process flow. Accurate estimation of the pre-lithium amount is a prerequisite for determining the accurate conversion efficiency.

[0005] In the prior art, the following means are usually used to determine the pre-lithium amount: the difference in first charge / first discharge capacity between the pre-lithium battery cell and the non-pre-lithium battery cell is calculated, and the pre-lithium amount is determined based on the above capacity difference. Since in the actual test process, a considerable portion of the lithium ions in the electrode plate that has been treated with pre-lithium do not show embedding / ejection during the first charge / first discharge, the accuracy of the pre-lithium amount determined by the above method is relatively low. Summary of the invention

[0006] The present invention provides a method, device, equipment and storage medium for estimating the pre-lithium amount of a lithium-ion battery, so as to achieve the purpose of accurately determining the pre-lithium amount.

[0007] In a first aspect, an embodiment of the present invention provides a method for estimating a pre-lithium amount of a lithium-ion battery, comprising:

[0008] Obtain a first charging curve of a pre-lithium lithium-ion battery cell, and obtain a second charging curve of a lithium-ion battery cell;

[0009] translating the first charging curve along the coordinate axis until the degree of overlap with the second charging curve reaches a set degree of overlap;

[0010] The translation amount of the first charging curve is obtained, and the actual pre-lithiation amount of the pre-lithiation lithium-ion battery is determined according to the translation amount.

[0011] Optionally, before obtaining the first charging curve of the pre-lithium lithium-ion battery cell and obtaining the second charging curve of the lithium-ion battery cell, the method further includes:

[0012] Obtain a first characteristic peak curve of a pre-lithium lithium-ion battery cell and a second characteristic peak curve of a lithium-ion battery cell;

[0013] Determining whether the positions of a first characteristic peak in the first characteristic peak curve and a second characteristic peak in the second characteristic peak curve on the coordinate axis are the same;

[0014] If the first characteristic peak and the second characteristic peak are at the same position, a first charging curve of the pre-lithium lithium-ion battery cell and a second charging curve of the lithium-ion battery cell are obtained.

[0015] Optionally, the first characteristic peak curve and the second characteristic peak curve include one or more of a differential capacity-voltage curve, a differential capacity-SOC curve, and a capacitance-voltage curve.

[0016] Optionally, the first charging curve and the second charging curve include voltage-capacity curves.

[0017] Optionally, the first characteristic peak curve is generated by first charging test data of the pre-lithium lithium-ion battery cell.

[0018] Optionally, the second characteristic peak curve is generated by first charging test data of the lithium-ion battery cell.

[0019] Optionally, the first charging curve is generated by first charging test data for the pre-lithium lithium-ion battery cell.

[0020] Optionally, the second charging curve is generated by first charging test data for the lithium-ion battery cell.

[0021] Optionally, if the following formula is satisfied, it is determined that the first charging curve and the second charging curve reach the set overlap degree:

[0022]

[0023] In the above formula, x i is the i-th sampling point in the first charging curve, y i is the i-th sampling point in the second charging curve, n is the number of sampling points, and ε is the coincidence threshold.

[0024] Optionally, the first charging curve is translated along the horizontal axis according to a specified step length, and each time the translation is performed, it is determined whether the degree of overlap between the first charging curve and the second charging curve reaches a set degree of overlap.

[0025] Optionally, after each translation, the sampling point sequence of the second charging curve remains unchanged;

[0026] The sampling point sequence of the first charging curve is: based on the previous sampling point sequence, each sampling point is summed with the step length during translation.

[0027] In a second aspect, an embodiment of the present invention further provides a lithium-ion battery pre-lithium amount estimation device, including a pre-lithium amount estimation unit, wherein the pre-lithium amount estimation unit is used to:

[0028] Obtain a first charging curve of a pre-lithium lithium-ion battery cell, and obtain a second charging curve of a lithium-ion battery cell;

[0029] translating the first charging curve along the coordinate axis until the degree of overlap with the second charging curve reaches a set degree of overlap;

[0030] The translation amount of the first charging curve is obtained, and the actual pre-lithiation amount of the pre-lithiation lithium-ion battery is determined according to the translation amount.

[0031] In a third aspect, an embodiment of the present invention further provides an electronic device, comprising at least one processor, and a memory communicatively connected to the at least one processor;

[0032] The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute the lithium-ion battery pre-lithium amount estimation method described in the embodiment of the present invention.

[0033] In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium, characterized in that the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the lithium-ion battery pre-lithium quantity estimation method recorded in the embodiment of the present invention when executed.

[0034] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention proposes a method for estimating the pre-lithium amount of a lithium-ion battery, in which a first charging curve of a pre-lithium lithium-ion battery cell and a second charging curve of the lithium-ion battery cell are obtained; the first charging curve is translated along the coordinate axis until the degree of overlap with the second charging curve reaches a set degree of overlap; the translation amount of the first charging curve is obtained, and the actual pre-lithium amount of the pre-lithium lithium-ion battery is determined according to the translation amount. After experimental analysis, when the actual pre-lithium amount is determined by the translation amount determined by the above method, the estimation accuracy of the actual pre-lithium amount is high. In addition, the execution time of the pre-lithium amount estimation method is short and the execution efficiency is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a flow chart of a method for estimating the amount of lithium in a lithium-ion battery in an embodiment;

[0036] Figure 2 is a schematic diagram of a charging curve in an embodiment;

[0037] Figure 3 is a schematic diagram of a charging curve after translation in an embodiment;

[0038] Figure 4 is another flow chart of a method for estimating the amount of lithium in a lithium-ion battery in an embodiment;

[0039] Figure 5 is a schematic diagram of a differential capacity-voltage curve in an embodiment;

[0040] Figure 6 Schematic diagram of the structure of an electronic device in an embodiment. DETAILED DESCRIPTION

[0041] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0042] Embodiment 1

[0043] Figure 1 is a flow chart of the lithium ion battery pre-lithium amount estimation method in the embodiment, refer to Figure 1 , the method comprising:

[0044] S101. Obtain a first charging curve of a pre-lithium lithium-ion battery cell, and obtain a second charging curve of the lithium-ion battery cell.

[0045] Illustratively, in this embodiment, the pre-lithium-ion lithium-ion battery cell is a battery cell that has undergone a pre-lithium treatment, and the lithium-ion battery cell is a battery cell that has not undergone a pre-lithium treatment.

[0046] Illustratively, in this embodiment, the pre-lithium lithium ion battery cell and the lithium ion battery cell meet the following conditions: before the pre-lithium treatment, the structure of the pre-lithium lithium ion battery cell (including the electrode component) is the same as that of the lithium ion battery cell.

[0047] For example, in this embodiment, the pre-lithium treatment method is not specifically limited, and any method in the prior art can be used for the pre-lithium treatment.

[0048] Illustratively, in this embodiment, the method for estimating the pre-lithium amount of a lithium-ion battery is particularly suitable for estimating the pre-lithium amount of a negative electrode sheet when a negative electrode sheet is pre-lithium treated by a negative electrode early formation method.

[0049] Exemplarily, in this embodiment, the negative electrode early formation method is:

[0050] Lithium metal is attached to the negative electrode sheet, and the electrolyte is allowed to penetrate into the negative electrode sheet through a single injection. Through the potential difference between the lithium metal and the negative electrode sheet, a portion of active lithium ions are embedded in the negative electrode, that is, a surface passivation layer (SEI film) is formed on the surface of the negative electrode.

[0051] Exemplarily, in this embodiment, the charging start cell capacity corresponding to the first charging curve is recorded as the first cell capacity, and the charging start cell capacity corresponding to the second charging curve is recorded as the second cell capacity;

[0052] The capacity of the first battery cell is limited to be the same as the capacity of the second battery cell. At the same time, the horizontal and vertical coordinate types of the first charging curve and the second charging curve are limited to be the same. When obtaining the first charging curve and the second charging curve, the corresponding charging test conditions are the same.

[0053] Figure 2 is a schematic diagram of the charging curve in the embodiment, refer to Figure 2 In one possible implementation, the charging curve of the pre-lithium battery cell (first charging curve) and the charging curve of the non-pre-lithium battery cell (second charging curve) use a voltage-capacity curve.

[0054] S102. translating the first charging curve along the coordinate axis until the degree of overlap with the second charging curve reaches a set degree of overlap.

[0055] Exemplarily, in this embodiment, Figure 3 Taking the charging curve shown as an example, the first charging curve is translated to the right according to the specified step size along the horizontal axis direction. Each time it is translated, it is determined whether the overlap degree between the first charging curve and the second charging curve reaches the set overlap degree.

[0056] Illustratively, in this embodiment, there is no specific limitation on the method for determining the degree of overlap between the first charging curve and the second charging curve. It is possible to determine whether the charging curves reach a set degree of overlap based on any curve similarity determination method in the prior art. If the similarity is greater than the set similarity, it is possible to determine that the degree of overlap between the first charging curve and the second charging curve reaches the set degree of overlap.

[0057] Exemplarily, whether the first charging curve and the second charging curve reach a set overlap degree can also be determined by the following formula:

[0058]

[0059] In the above formula, x i is the i-th sampling point in the first charging curve, y i is the i-th sampling point in the second charging curve, n is the number of sampling points, and ε is the coincidence threshold.

[0060] Exemplarily, the specific values ​​of the number of sampling points and the overlap threshold can be set according to design requirements and are not specifically limited in this solution.

[0061] If, after calculation, the sampling points in the first charging curve and the second charging curve satisfy the above formula, it is determined that the first charging curve and the second charging curve reach a set overlap degree.

[0062] Exemplarily, in the above solution, it is set that after each translation, the sampling point sequence of the second charging curve remains unchanged;

[0063] The sampling point sequence of the first charging curve is: on the basis of the previous sampling point sequence, each sampling point is summed with the step length during translation.

[0064] S103. Obtain the translation amount of the first charging curve, and determine the actual pre-lithiation amount of the pre-lithiation lithium-ion battery according to the translation amount.

[0065] Exemplarily, in this embodiment, when the overlap between the first charging curve and the second charging curve reaches a set overlap, the translation amount of the first charging curve from the starting position to the translation end position is determined, and the actual pre-lithium amount of the pre-lithium lithium-ion battery is determined based on this.

[0066] Exemplarily, in this embodiment, the actual pre-lithium amount is used to represent the mass of active lithium ions stored in the electrode piece after the electrode piece of the battery cell is pre-lithium treated.

[0067] Exemplarily, in this embodiment, the corresponding relationship between the translation amount and the actual pre-lithiation amount can be determined through a calibration test.

[0068] Figure 3 is a schematic diagram of the charging curve after translation in the embodiment, refer to Figure 3 , the abscissa of the charging curve (first charging curve) of the pre-lithium battery cell is the battery cell capacity, that is, the unit of the obtained translation amount is the battery cell capacity (mAh);

[0069] Based on the above cell capacity, the actual pre-lithium amount can be determined according to the calibrated gram (lithium ion mass)-capacity (cell capacity) correspondence.

[0070] Illustratively, in this embodiment, based on the actual pre-lithium amount, the conversion rate of lithium metal into active lithium ions stored in the electrode during pre-lithium treatment can be calculated, wherein the conversion rate can be used as a basis for optimizing the process flow of pre-lithium treatment.

[0071] For example, by optimizing the pre-lithium treatment process, it is possible to avoid excessive lithium coating on the negative electrode sheet, which may lead to excessive negative electrode and lithium deposition in the battery cell.

[0072] And to avoid the problem that the initial efficiency of the battery cell does not meet the design requirements when the battery cell is charged or discharged for the first time due to too little lithium coating on the negative electrode.

[0073] The present embodiment proposes a method for estimating the pre-lithium amount of a lithium-ion battery. In the method, a first charging curve of a pre-lithium lithium-ion battery cell and a second charging curve of the lithium-ion battery cell are obtained; the first charging curve is translated along the coordinate axis until the degree of overlap with the second charging curve reaches a set degree of overlap; the translation amount of the first charging curve is obtained, and the actual pre-lithium amount of the pre-lithium lithium-ion battery is determined according to the translation amount. After experimental analysis, when the actual pre-lithium amount is determined by using the translation amount determined in the above manner, the estimation accuracy of the actual pre-lithium amount is high. In addition, the execution time of the pre-lithium amount estimation method is short and the execution efficiency is high.

[0074] Figure 4 is another flow chart of a lithium ion battery pre-lithium quantity estimation method in an embodiment, refer to Figure 4 As an implementable embodiment, the method includes:

[0075] S201. Obtain a first characteristic peak curve of a pre-lithium lithium-ion battery cell and a second characteristic peak curve of a lithium-ion battery cell.

[0076] Exemplarily, in this solution, the pre-lithium-ion lithium-ion battery cell is a battery cell that has undergone a pre-lithium treatment, and the lithium-ion battery cell is a battery cell that has not undergone a pre-lithium treatment.

[0077] Exemplarily, in this embodiment, the characteristic peak is a peak point in a test (eg, a charge test, a discharge test, or a setting test) curve that can reflect the electrochemical reaction characteristics of the battery cell.

[0078] Figure 5 is a schematic diagram of the differential capacity-voltage curve in the embodiment, refer to Figure 5 Taking the differential capacity-voltage curve (dQ / dV-V curve) of a non-pre-lithium battery as an example, the curve includes two characteristic peaks, and the voltage values ​​corresponding to the characteristic peaks can be used to represent the platform voltage of the non-pre-lithium battery.

[0079] Exemplarily, in this embodiment, the specific type of the characteristic peak curve is not limited, as long as the curve contains the characteristic peak. In addition to the differential capacity-voltage curve, the characteristic peak curve can also be a differential capacity-SOC curve (dQ / dV-SOC curve), a capacitance-voltage curve (CV curve), etc.

[0080] S202. Determine whether the positions of the first characteristic peak in the first characteristic peak curve and the second characteristic peak in the second characteristic peak curve on the coordinate axis are the same.

[0081] Exemplarily, in this embodiment, one characteristic peak curve may be used or multiple characteristic peak curves may be used simultaneously.

[0082] Exemplarily, if a characteristic peak curve is used, and the characteristic peak curve includes multiple characteristic peaks, then it is specifically determined whether the first characteristic peak curve and the second characteristic peak curve include the same number of characteristic peaks;

[0083] When the same number of characteristic peaks are included, it is determined in turn along the coordinate axis whether the positions of each group of characteristic peaks in the two characteristic peak curves on the coordinate axis are the same.

[0084] Exemplarily, when multiple characteristic peak curves are used, for each characteristic peak curve, the method for determining whether the positions of the first characteristic peak and the second characteristic peak on the coordinate axis are the same is the same as the determination method when one characteristic peak curve is used;

[0085] If for each characteristic peak curve, the first characteristic peak and the second characteristic peak have the same position on the coordinate axis, then it is determined that the first characteristic peak in the first characteristic peak curve and the second characteristic peak in the second characteristic peak curve have the same position on the coordinate axis.

[0086] Exemplarily, in one possible implementation scheme, a characteristic peak curve is used, and the characteristic peak curve is a dQ / dV-V curve.

[0087] For example, Figure 5 Taking the differential capacity-voltage curve (first characteristic peak curve) of the pre-lithium battery cell and the differential capacity-voltage curve (second characteristic peak curve) of the non-pre-lithium battery cell as examples, the following method can be used to determine whether the positions of the characteristic peaks on the coordinate axis are the same:

[0088] Determining that the first characteristic peak curve contains two characteristic peaks, the second characteristic peak curve contains two characteristic peaks, and determining that the first characteristic peak curve and the second characteristic peak curve contain the same number of characteristic peaks;

[0089] Obtaining a first voltage corresponding to a first characteristic peak in the first characteristic peak curve, and obtaining a second voltage corresponding to a first characteristic peak in the second characteristic peak curve;

[0090] Determine whether the difference between the first voltage and the second voltage is within a set difference range, and if so, determine that the first characteristic peak in the first characteristic peak curve is at the same position as the first characteristic peak in the second characteristic peak curve;

[0091] Obtaining a third voltage corresponding to the second characteristic peak in the first characteristic peak curve, and obtaining a fourth voltage corresponding to the second characteristic peak in the second characteristic peak curve;

[0092] Determine whether the difference between the third voltage and the fourth voltage is within a set difference range, and if so, determine that the second characteristic peak in the first characteristic peak curve is at the same position as the second characteristic peak in the second characteristic peak curve;

[0093] If the first characteristic peak in the first characteristic peak curve is at the same position as the first characteristic peak in the second characteristic peak curve, and the second characteristic peak in the first characteristic peak curve is at the same position as the second characteristic peak in the second characteristic peak curve, then determine whether the first characteristic peak in the first characteristic peak curve and the second characteristic peak in the second characteristic peak curve are at the same position on the coordinate axis.

[0094] S203. If the positions of the first characteristic peak and the second characteristic peak are the same, obtaining a first charging curve of the pre-lithium lithium-ion battery cell and a second charging curve of the lithium-ion battery cell.

[0095] Exemplarily, when the first characteristic peak in a first characteristic peak curve of a pre-lithium lithium-ion battery cell is at the same position as the second characteristic peak in a second characteristic peak curve of a lithium-ion battery cell;

[0096] A charging curve of the same pre-lithium lithium-ion battery cell is obtained, which is recorded as a first charging curve, and a charging curve of the same lithium-ion battery cell is obtained, which is recorded as a second charging curve.

[0097] Exemplarily, in this solution, the charging start cell capacity corresponding to the first charging curve is recorded as the first cell capacity, and the charging start cell capacity corresponding to the second charging curve is recorded as the second cell capacity;

[0098] The capacity of the first battery cell is limited to be the same as the capacity of the second battery cell. At the same time, the horizontal and vertical coordinate types of the first charging curve and the second charging curve are limited to be the same. When obtaining the first charging curve and the second charging curve, the corresponding charging test conditions are the same.

[0099] S204. Shift the first charging curve along the coordinate axis until the degree of overlap with the second charging curve reaches a set degree of overlap.

[0100] S205. Obtain the translation amount of the first charging curve, and determine the actual pre-lithiation amount of the pre-lithiation lithium-ion battery according to the translation amount.

[0101] Exemplarily, in this solution, the implementation methods of step S204 and step S205 are the same as the corresponding contents recorded in step S102 and step S103.

[0102] exist Figure 1 On the basis of the scheme shown, in the method proposed in this scheme, the first characteristic peak curve of the pre-lithium lithium-ion battery cell and the second characteristic peak curve of the lithium-ion battery cell are judged. By judging the first characteristic peak in the first characteristic peak curve and the second characteristic peak in the second characteristic peak curve, it is possible to automatically and accurately judge whether the structures of the pre-lithium lithium-ion battery cell and the lithium-ion battery cell meet the set requirements.

[0103] Exemplarily, based on the content recorded in step S101, in a possible implementation scheme, the first charging curve is generated by the first charging test data for the pre-lithium lithium-ion battery cell; the second charging curve is generated by the first charging test data for the lithium-ion battery cell.

[0104] In this solution, the first charging test data of the pre-lithium lithium-ion battery is used to generate the first charging curve, and the first charging test data of the lithium-ion battery is used to generate the second charging curve. The number of tests required to generate the charging curve is small, and the test time cost is low.

[0105] Exemplarily, based on the content recorded in step S201, in one possible implementation scheme, the characteristic peak curve adopts a dQ / dV-V curve, and it is defined that the first characteristic peak curve is generated by the first charging test data for a pre-lithium lithium-ion battery cell; the second characteristic peak curve is generated by the first charging test data for a lithium-ion battery cell.

[0106] In this solution, the first characteristic peak curve is generated by using the first charging test data of the pre-lithium lithium-ion battery, and the second characteristic peak curve is generated by using the first charging test data of the lithium-ion battery. The number of tests required to generate the characteristic peak curves is small, and the test time cost is low.

[0107] Embodiment 2

[0108] This embodiment provides a lithium-ion battery pre-lithium amount estimation device, including a pre-lithium amount estimation unit, which is used to:

[0109] Obtain a first charging curve of a pre-lithium lithium-ion battery cell, and obtain a second charging curve of a lithium-ion battery cell;

[0110] translating the first charging curve along the coordinate axis until the degree of overlap with the second charging curve reaches a set degree of overlap;

[0111] The translation amount of the first charging curve is obtained, and the actual pre-lithiation amount of the pre-lithiation lithium-ion battery is determined according to the translation amount.

[0112] Exemplarily, in this embodiment, the pre-lithium amount estimation unit can be configured to implement any one of the lithium-ion battery pre-lithium amount estimation methods recorded in Example 1, and its specific implementation methods and beneficial effects are the same as the corresponding contents recorded in Example 1, which will not be repeated here.

[0113] Embodiment 3

[0114] Figure 6A schematic diagram of the structure of an electronic device 10 that can be used to implement an embodiment of the present invention is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices (such as helmets, glasses, watches, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present invention described and / or required herein.

[0115] like Figure 6 As shown, the electronic device 10 includes at least one processor 11, and a memory connected to the at least one processor 11, such as a read-only memory (ROM) 12, a random access memory (RAM) 13, etc., wherein the memory stores a computer program that can be executed by at least one processor, and the processor 11 can perform various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 12 or the computer program loaded from the storage unit 18 to the random access memory (RAM) 13. In the RAM 13, various programs and data required for the operation of the electronic device 10 can also be stored. The processor 11, the ROM 12, and the RAM 13 are connected to each other through a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0116] A number of components in the electronic device 10 are connected to the I / O interface 15, including: an input unit 16, such as a keyboard, a mouse, etc.; an output unit 17, such as various types of displays, speakers, etc.; a storage unit 18, such as a disk, an optical disk, etc.; and a communication unit 19, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 19 allows the electronic device 10 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0117] The processor 11 may be a variety of general and / or special processing components with processing and computing capabilities. Some examples of the processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various dedicated artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The processor 11 executes the various methods and processes described above, such as a lithium-ion battery pre-lithium amount estimation method.

[0118] In some embodiments, the lithium-ion battery pre-lithium quantity estimation method may be implemented as a computer program, which is tangibly contained in a computer-readable storage medium, such as a storage unit 18. In some embodiments, part or all of the computer program may be loaded and / or installed on the electronic device 10 via the ROM 12 and / or the communication unit 19. When the computer program is loaded into the RAM 13 and executed by the processor 11, one or more steps of the lithium-ion battery pre-lithium quantity estimation method described above may be performed. Alternatively, in other embodiments, the processor 11 may be configured to perform the lithium-ion battery pre-lithium quantity estimation method in any other appropriate manner (e.g., by means of firmware).

[0119] Various implementations of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chips (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various implementations can include: being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0120] Computer programs for implementing the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that when the computer program is executed by the processor, the functions / operations specified in the flow chart and / or block diagram are implemented. The computer program may be executed entirely on the machine, partially on the machine, partially on the machine and partially on a remote machine as a stand-alone software package, or entirely on a remote machine or server.

[0121] In the context of the present invention, a computer-readable storage medium may be a tangible medium that may contain or store a computer program for use by or in conjunction with an instruction execution system, device, or equipment. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, or equipment, or any suitable combination of the foregoing. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. A more specific example of a machine-readable storage medium may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0122] To provide interaction with a user, the systems and techniques described herein may be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and a pointing device (e.g., a mouse or trackball) through which the user can provide input to the electronic device. Other types of devices may also be used to provide interaction with the user; for example, the feedback provided to the user may be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user may be received in any form (including acoustic input, voice input, or tactile input).

[0123] The systems and techniques described herein may be implemented in a computing system that includes backend components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes frontend components (e.g., a user computer with a graphical user interface or a web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such backend components, middleware components, or frontend components. The components of the system may be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), a blockchain network, and the Internet.

[0124] A computing system may include a client and a server. The client and the server are generally remote from each other and usually interact through a communication network. The client and server relationship is generated by computer programs running on the corresponding computers and having a client-server relationship with each other. The server may be a cloud server, also known as a cloud computing server or cloud host, which is a host product in the cloud computing service system to solve the defects of difficult management and weak business scalability in traditional physical hosts and VPS services.

[0125] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A method for estimating the amount of lithium in a lithium-ion battery, characterized in that: include: Obtain a first charging curve of a pre-lithium lithium-ion battery cell, and obtain a second charging curve of a lithium-ion battery cell; translating the first charging curve along the coordinate axis until the degree of overlap with the second charging curve reaches a set degree of overlap; The translation amount of the first charging curve is obtained, and the actual pre-lithium amount of the pre-lithium lithium-ion battery cell is determined according to the translation amount. The corresponding relationship between the translation amount and the actual pre-lithium amount is determined by a calibration test.

2. The method for estimating the pre-lithium amount of a lithium-ion battery according to claim 1, wherein: include: Obtain a first characteristic peak curve of a pre-lithium lithium-ion battery cell and a second characteristic peak curve of a lithium-ion battery cell; Determining whether the positions of a first characteristic peak in the first characteristic peak curve and a second characteristic peak in the second characteristic peak curve on the coordinate axis are the same; If the first characteristic peak and the second characteristic peak are at the same position, obtaining a first charging curve of the pre-lithium lithium-ion battery cell and a second charging curve of the lithium-ion battery cell; translating the first charging curve along the coordinate axis until the degree of overlap with the second charging curve reaches a set degree of overlap; Acquire a translation amount of the first charging curve, and determine an actual pre-lithiation amount of the pre-lithiation lithium-ion battery cell according to the translation amount; The first characteristic peak curve and the second characteristic peak curve include one or more of a differential capacity-voltage curve, a differential capacity-SOC curve, and a capacitance-voltage curve.

3. The method for estimating the pre-lithium amount of a lithium-ion battery according to claim 1, wherein: The first charging curve and the second charging curve include voltage-capacity curves.

4. The method for estimating the pre-lithium amount of a lithium-ion battery according to claim 1, wherein: If the following formula is satisfied, it is determined that the first charging curve and the second charging curve reach the set overlap degree: ； In the above formula, is the i-th sampling point in the first charging curve, is the i-th sampling point in the second charging curve, n is the number of sampling points, is the overlap threshold.

5. The method for estimating the pre-lithium amount of a lithium-ion battery according to claim 4, wherein: The first charging curve is translated along the horizontal axis according to a specified step length, and each time the translation is performed, it is determined whether the overlap between the first charging curve and the second charging curve reaches the set overlap.

6. The method for estimating the pre-lithium amount of a lithium-ion battery according to claim 5, wherein: It is set that after each translation, the sampling point sequence of the second charging curve remains unchanged; The sampling point sequence of the first charging curve is: based on the previous sampling point sequence, each sampling point is summed with the step length during translation.

7. A lithium-ion battery pre-lithium quantity estimation device, characterized in that: A pre-lithium amount estimation unit is included, and the pre-lithium amount estimation unit is used to: Obtain a first charging curve of a pre-lithium lithium-ion battery cell, and obtain a second charging curve of a lithium-ion battery cell; translating the first charging curve along the coordinate axis until the degree of overlap with the second charging curve reaches a set degree of overlap; The translation amount of the first charging curve is obtained, and the actual pre-lithium amount of the pre-lithium lithium-ion battery cell is determined according to the translation amount. The corresponding relationship between the translation amount and the actual pre-lithium amount is determined by a calibration test.

8. An electronic device, characterized in that: comprising at least one processor, and a memory communicatively connected to the at least one processor; The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute the lithium-ion battery pre-lithium amount estimation method according to any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the lithium-ion battery pre-lithium quantity estimation method according to any one of claims 1 to 6 when executed.

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