CN115007503B - Cell sorting method, device, equipment and storage medium - Google Patents

Abstract

The invention discloses a method, a device, equipment and a storage medium for sorting electric cores. The cell sorting method comprises the following steps: acquiring formation voltage record data, and determining a first voltage inflection point, a second voltage inflection point and formation termination voltage in the formation voltage record data; determining a first voltage rising rate between the first voltage inflection point and the second voltage inflection point, and determining a second voltage rising rate between the second voltage inflection point and the formation termination voltage; acquiring a first open-circuit voltage after the first discharge phase is ended, acquiring a second open-circuit voltage after the second discharge phase is ended, and acquiring a third open-circuit voltage after the third discharge phase is ended; determining a first open-circuit voltage difference according to the first open-circuit voltage and the second open-circuit voltage, and determining a second open-circuit voltage difference according to the second open-circuit voltage and the third open-circuit voltage; and performing cell sorting according to the formation termination voltage, the first voltage rising rate, the second voltage rising rate, the first open circuit voltage difference and the second open circuit voltage difference.

Description

A cell sorting method, device, equipment and storage medium

technical field

Embodiments of the present invention relate to battery testing technology, and in particular to a battery cell sorting method, device, equipment and storage medium.

Background technique

In the production process of battery packs, batteries with high consistency need to be used to form battery modules to ensure the normal use of battery packs. At present, batteries with consistency are mainly screened out through the battery sorting process.

Cell sorting can be divided into static sorting and dynamic sorting. Static sorting is the primary sorting method in the lithium battery industry. In static sorting, it is necessary to measure the K value, capacity, internal resistance, open circuit voltage, etc. of the cell. According to the values of the above parameters, the batteries are sorted. Static sorting has the following defects: it is difficult to obtain parameters, and it needs to go through multiple processes, resulting in a long cycle of the entire sorting process; it cannot reflect the characteristics of the parameters in the working process of the battery, and cannot accurately summarize the future characteristics of the battery cell.

Contents of the invention

The invention provides a cell sorting method, device, equipment and storage medium to achieve the purpose of simplifying the cell sorting process.

In the first aspect, an embodiment of the present invention provides a cell sorting method, including:

Acquiring the formation voltage record data, and determining the first voltage inflection point, the second voltage inflection point, and the formation end voltage in the formation voltage record data;

determining a first voltage rise rate between the first voltage inflection point and the second voltage inflection point, and determining a second voltage rise rate between the second voltage inflection point and the formation end voltage;

Obtaining the first open circuit voltage after the end of the first discharge stage, obtaining the second open circuit voltage after the end of the second discharge stage, and obtaining the third open circuit voltage after the end of the third discharge stage;

determining the first open circuit voltage difference according to the first open circuit voltage and the second open circuit voltage, and determining the second open circuit voltage difference according to the second open circuit voltage and the third open circuit voltage;

Cell sorting is performed according to the formation end voltage, the first voltage rise rate, the second voltage rise rate, the first open circuit voltage difference and the second open circuit voltage difference.

Optionally, the first voltage inflection point ranges from 1.8V to 2.2V;

The range of the second voltage inflection point is 2.8V-3.2V;

The range of the formation termination voltage is 3.6V-4.0V.

Optionally, the first discharge stage includes discharging the cell from the formation termination voltage to a set SOC value.

Optionally, the second discharge stage includes the cells standing still under the first temperature condition for a first period of time.

Optionally, the third discharge stage includes standing the battery cell under the second temperature condition for a second duration.

Optionally, performing cell sorting according to the formation termination voltage, the first voltage rise rate, the second voltage rise rate, the first open circuit voltage difference, and the second open circuit voltage difference includes:

The first sorting is performed according to the formation termination voltage, the second sorting is performed according to the first voltage rising rate and the second voltage rising rate, and the third sorting is performed according to the first open circuit voltage difference and the second open circuit voltage difference.

Optionally, the set SOC value is 2%-7% SOC.

In the second aspect, the embodiment of the present invention also provides a cell sorting device, including a cell sorting unit, and the cell sorting unit is used for:

Acquiring the formation voltage record data, and determining the first voltage inflection point, the second voltage inflection point, and the formation end voltage in the formation voltage record data;

determining a first voltage rise rate between the first voltage inflection point and the second voltage inflection point, and determining a second voltage rise rate between the second voltage inflection point and the formation end voltage;

Obtaining the first open circuit voltage after the end of the first discharge stage, obtaining the second open circuit voltage after the end of the second discharge stage, and obtaining the third open circuit voltage after the end of the third discharge stage;

determining the first open circuit voltage difference according to the first open circuit voltage and the second open circuit voltage, and determining the second open circuit voltage difference according to the second open circuit voltage and the third open circuit voltage;

Cell sorting is performed according to the formation end voltage, the first voltage rise rate, the second voltage rise rate, the first open circuit voltage difference and the second open circuit voltage difference.

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

The memory stores a computer program that can be executed 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 cell analysis described in the embodiment of the present invention. Choose method.

In a fourth aspect, an embodiment of the present invention also provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the present invention when executing The cell sorting method described in the embodiment.

Compared with the prior art, the beneficial effect of the present invention is that: the present invention proposes a cell sorting method, in which method, the final formation voltage, the first voltage rise rate, and the second voltage rise rate are obtained when the cells are formed. , the first open-circuit voltage difference and the second open-circuit voltage difference when the cell is discharged, and the cell is divided according to the formation end voltage, the first voltage rise rate, the second voltage rise rate, the first open-circuit voltage difference and the second open-circuit voltage difference The data used in cell sorting is less difficult to obtain and has high acquisition efficiency, which can reduce the process flow of cell sorting.

Description of drawings

Fig. 1 is the flow chart of the cell sorting method in the embodiment;

Fig. 2 is a schematic structural diagram of the electronic device in the embodiment.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, but not to limit the present invention. In addition, it should be noted that, for the convenience of description, only some structures related to the present invention are shown in the drawings but not all structures.

Embodiment one

Fig. 1 is a flow chart of the cell sorting method in the embodiment, referring to Fig. 1, the cell sorting method includes:

S101. Acquire the formation voltage record data, and determine the first voltage inflection point, the second voltage inflection point, and the formation end voltage in the formation voltage record data.

In this embodiment, the battery cell sorting method is applicable to battery cells that have been chemically formed, that is, the battery cells should first be chemically formed before sorting the battery cells.

Exemplarily, in this embodiment, the formation voltage record data is the cell voltage change data recorded during the cell formation process.

Exemplarily, in this embodiment, on the time axis, cell voltage change rates before and after the first voltage inflection point are different, and cell voltage change rates before and after the second voltage inflection point are different.

Exemplarily, in this embodiment, the method of determining the first voltage inflection point and the second voltage inflection point is not specifically limited. For example, for the formation voltage curve, the rate of change of the curve in the discrete interval can be calculated based on the definition of the derivative, and then determined above voltage inflection point.

Exemplarily, in this embodiment, the end voltage of formation is used to represent the open circuit voltage of the cell at the end of formation.

Exemplarily, in this embodiment, on the time axis, the first voltage inflection point, the second voltage inflection point, and the formation end voltage appear sequentially, and numerically, the first voltage inflection point, the second voltage inflection point, and the formation end voltage increase sequentially .

Exemplarily, in a possible implementation, the first voltage inflection point ranges from 1.8V to 2.2V, the second voltage inflection point ranges from 2.8V to 3.2V, and the formation end voltage ranges from 3.6V to 4.0V.

S102. Determine the first voltage rise rate between the first voltage inflection point and the second voltage inflection point, and determine the second voltage rise rate between the second voltage inflection point and the formation end voltage.

Exemplarily, in this embodiment, the first voltage rise rate is determined in the following manner:

In the above formula, K ₁ is the first voltage rising rate, V ₁ is the first voltage inflection point, V ₂ is the second voltage inflection point, and t ₁ is the time length between the first voltage inflection point and the second voltage inflection point.

Exemplarily, in this embodiment, the second voltage generation rate is determined in the following manner:

In the above formula, K ₂ is the first voltage rising rate, V ₂ is the second voltage inflection point, V ₃ is the formation end voltage, and t ₂ is the time between the second voltage inflection point and the formation end voltage.

S103. Acquire a first open circuit voltage after the first discharge stage, obtain a second open circuit voltage after the second discharge stage, and obtain a third open circuit voltage after the third discharge stage.

Exemplarily, in this embodiment, the first open circuit voltage, the second open circuit voltage, and the third open circuit voltage are the recorded open circuit voltages of the battery cell at a specified node when the battery cell is discharged;

Specifically, in this embodiment, the first open-circuit voltage is the open-circuit voltage of the cell after the first discharge stage, the second open-circuit voltage is the open-circuit voltage of the cell after the second discharge stage, and the third open-circuit voltage is the third discharge voltage. The open circuit voltage of the cell after the phase is over.

Exemplarily, in this embodiment, in the first discharge phase, the second discharge phase, and the third discharge phase, the target discharge voltage or environmental parameters of the cells are different from each other.

Exemplarily, in this embodiment, the first discharge stage, the second discharge stage, and the third discharge stage can be the discharge of the cell from the end-of-formation voltage to the set SOC value, high-temperature static cell, and low-temperature static cell. Permutations.

Exemplarily, in one possible implementation, the first discharge stage can be set as: discharge the battery (battery cell) from the end-of-formation voltage to the set SOC value; set the second discharge stage as discharge the battery at the first Standing for a first time period under the temperature condition; setting the third discharge stage as placing the battery under the second temperature condition for a second time period.

Exemplarily, in this solution, the set SOC value ranges from 2% to 7% SOC, for example, the set SOC value can be selected to be 5% SOC.

Exemplarily, in this solution, the first temperature condition is set as high temperature (60-80°C), and the first duration is 10 hours; the second temperature condition is set as low temperature (-40--20°C), and the second duration is for 10 hours.

S104. Determine the first open circuit voltage difference according to the first open circuit voltage and the second open circuit voltage, and determine the second open circuit voltage difference according to the second open circuit voltage and the third open circuit voltage.

Exemplarily, in this embodiment, the first open circuit voltage difference is determined according to the following formula:

ΔOCV ₁ =COV ₂ -OCV ₁

In the above formula, ΔOCV ₁ is the first open circuit voltage difference, OCV ₁ is the first open circuit voltage, and COV ₂ is the second open circuit voltage.

Exemplarily, in this embodiment, the second open circuit voltage difference is determined according to the following formula:

ΔOCV ₂ =COV ₃ -OCV ₂

In the above formula, ΔOCV ₂ is the second open circuit voltage difference, OCV ₂ is the second open circuit voltage, and COV ₃ is the third open circuit voltage.

S105. Perform cell sorting according to the formation end voltage, the first voltage rise rate, the second voltage rise rate, the first open circuit voltage difference, and the second open circuit voltage difference.

Exemplarily, in this embodiment, the cells can be sorted according to the values of the formation end voltage, the first voltage rise rate, the second voltage rise rate, the first open circuit voltage difference, and the second open circuit voltage difference.

For example, one sorting can be carried out according to the formation end voltage, two sorting can be carried out according to the first open circuit voltage difference, three sorting can be carried out according to the second open circuit voltage difference, four sorting can be carried out according to the first voltage rising rate, and four sorting can be carried out according to the second open circuit voltage difference. The voltage rise rate is sorted five times;

After the fifth sorting, the sorting results of the cells can be finally determined.

Exemplarily, in an implementation, cell sorting can be performed according to the following strategy:

performing one sorting according to the formation termination voltage, performing secondary sorting according to the first open circuit voltage difference and the second open circuit voltage difference, and performing three sorting according to the first voltage rising rate and the second voltage rising rate;

After the third sorting, the sorting results of the cells can be finally determined.

Exemplarily, in this solution, the primary sorting is performed based on the value of the formation end voltage, the secondary sorting is performed according to the sum of the first voltage rising rate and the second voltage rising rate, and the secondary sorting is performed according to the first open circuit voltage difference and the second open circuit voltage difference. The sum of the voltage differences performs three sorts.

Exemplarily, in this solution, the battery cells are sequentially sorted based on the formation end voltage, and then, the first voltage rising rate and the second voltage rising rate are used as indicators reflecting the charging and discharging efficiency of the battery cells and the quality of SEI film formation. Based on the first voltage rise rate and the second voltage rise rate, the cells are sorted for the second time. Finally, the first open circuit voltage difference and the second open circuit voltage difference are used as indicators to reflect the chemical self-discharge and physical self-discharge of the cells. Based on the basis of the first open-circuit voltage difference and the second open-circuit voltage difference, the cells are sorted three times. Based on the above-mentioned layer-by-layer sorting method, it can ensure that the cells have good consistency in all dimensions, and ensure that the cells have good consistency. Sorting effect.

This embodiment proposes a cell sorting method. In this method, the formation termination voltage, the first voltage rise rate, and the second voltage rise rate when the cell is formed, the first open circuit voltage difference and the second voltage rise rate when the cell is discharged are obtained. Two open circuit voltage differences, cell sorting is performed according to the end voltage of formation, the first voltage rise rate, the second voltage rise rate, the first open circuit voltage difference and the second open circuit voltage difference, and the difficulty of obtaining data used in cell sorting Low, high acquisition efficiency, can reduce the process flow of cell sorting.

Table 1 is the cell data table in the embodiment, and the data in Table 1 is obtained by the cells satisfying the following conditions:

When the cell is being discharged, set the first discharge stage to discharge the battery (cell) from the end-of-formation voltage to 5% SOC;

The second discharge stage is set to leave the battery at high temperature for 10 hours; the third discharge stage is set to leave the battery at low temperature for 10 hours.

Table 1

Exemplarily, according to the data in Table 1, when sorting the cells, one sorting is performed according to the value of the formation end voltage, and the second sorting is performed according to the sum of the first voltage rising rate and the second voltage rising rate, Three sortings are performed according to the sum of the first open circuit voltage difference and the second open circuit voltage difference.

Specifically, referring to Table 1, based on the formation end voltage, the cells are divided into two grades, that is, the cells whose formation end voltage is less than 3.204 are marked as M1, and the remaining cells are marked as M2;

For the battery M1, according to the sum of the first voltage rising rate and the second voltage rising rate, the battery M1 is divided into two levels, that is, the battery whose sum is less than 0.562 is marked as N1, and the remaining batteries are marked as N2;

For the cell M2, according to the sum of the first voltage rise rate and the second voltage rise rate, the cell M2 is divided into two grades, that is, the cell whose sum is less than 0.561 is marked as N3, and the remaining cells are marked as N4;

For the battery cell N1, according to the sum of the first open circuit voltage difference and the second open circuit voltage difference, the battery cell N1 is divided into two levels, that is, the battery cell whose sum is greater than 4.621 is marked as P1, and the remaining cells are marked as P2;

For the battery cell N2, according to the sum of the first open circuit voltage difference and the second open circuit voltage difference, the battery cell N2 is divided into two levels, that is, the battery cell whose sum is greater than 4.495 is marked as P3, and the remaining cells are marked as P4;

For the battery cell N3, according to the sum of the first open circuit voltage difference and the second open circuit voltage difference, the battery cell N3 is divided into two levels, that is, the battery cell whose sum is greater than 4.532 is marked as P5, and the remaining cells are marked as P6;

For the battery cell N4, according to the sum of the first open circuit voltage difference and the second open circuit voltage difference, the battery cell N4 is divided into two grades, that is, the battery cells whose sum is less than 4.755 are marked as P7, and the remaining cells are marked as P8.

Exemplarily, after sorting, the battery cells are finally divided into 8 grades, namely P1-P8, and the battery cells of the same grade can be considered to have the same charge and discharge performance, that is, have a high degree of consistency.

Exemplarily, in a possible implementation, before sorting the cells, the acquired data can also be preprocessed (including formation end voltage, first voltage rise rate, second voltage rise rate, first Open-circuit voltage, second open-circuit voltage, third open-circuit voltage), remove one or more sets of data containing abnormal data (such as scattered data that is obviously too large or too small), and then perform subsequent cell sorting work.

Embodiment two

This embodiment proposes a cell sorting device, including a cell sorting unit, which is used for:

Acquiring the formation voltage record data, determining the first voltage inflection point, the second voltage inflection point, and the formation end voltage in the formation voltage record data;

determining a first voltage rise rate between the first voltage inflection point and a second voltage inflection point, and determining a second voltage rise rate between the second voltage inflection point and the formation end voltage;

Obtaining the first open circuit voltage after the end of the first discharge stage, obtaining the second open circuit voltage after the end of the second discharge stage, and obtaining the third open circuit voltage after the end of the third discharge stage;

determining the first open circuit voltage difference according to the first open circuit voltage and the second open circuit voltage; determining the second open circuit voltage difference according to the second open circuit voltage and the third open circuit voltage;

Cell sorting is performed according to the formation end voltage, the first voltage rise rate, the second voltage rise rate, the first open circuit voltage difference and the second open circuit voltage difference.

Exemplarily, in this embodiment, the cell sorting unit can be specifically configured to implement any cell sorting method described in Embodiment 1, and its implementation process and beneficial effects are the same as those described in Embodiment 1 , which will not be repeated here.

Embodiment three

FIG. 2 shows a schematic structural diagram of an electronic device 10 that can be used to implement an embodiment of the present invention. Electronic device is intended to represent various forms of digital computers, such as laptops, desktops, workstations, personal digital assistants, servers, blade servers, mainframes, and other suitable computers. Electronic devices may also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices (eg, helmets, glasses, watches, etc.), and other similar computing devices. The components shown herein, their connections and relationships, and their functions, are by way of example only, and are not intended to limit implementations of the inventions described and/or claimed herein.

As shown in FIG. 2 , the electronic device 10 includes at least one processor 11, and a memory communicatively connected with 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 There is a computer program executable by at least one processor, and the processor 11 can operate according to a computer program stored in a read-only memory (ROM) 12 or loaded from a storage unit 18 into a random access memory (RAM) 13. Various appropriate actions and processes are performed. In the RAM 13, various programs and data necessary for the operation of the electronic device 10 are also stored. The processor 11 , ROM 12 , and 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 .

Multiple 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 magnetic disk, an optical disk etc.; and a communication unit 19, such as a network card, a modem, a wireless communication transceiver, and the like. 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.

Processor 11 may be various general and/or special purpose processing components having processing and computing capabilities. Some examples of processor 11 include, but are not limited to, central processing units (CPUs), graphics processing units (GPUs), various dedicated artificial intelligence (AI) computing chips, various processors that run machine learning model algorithms, digital signal processing processor (DSP), and any suitable processor, controller, microcontroller, etc. The processor 11 executes the various methods and processes described above, such as the cell sorting method.

In some embodiments, the cell sorting method can be implemented as a computer program, which is tangibly contained in a computer-readable storage medium, such as the 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 cell sorting method described above can be performed. Alternatively, in other embodiments, the processor 11 may be configured in any other appropriate way (for example, by means of firmware) to execute the cell sorting method.

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 Implemented in a system of systems (SOC), load programmable logic device (CPLD), computer hardware, firmware, software, and/or combinations thereof. These various embodiments may include being implemented in one or more computer programs executable and/or interpreted on a programmable system including at least one programmable processor, the programmable processor Can be special-purpose or general-purpose programmable processor, can receive data and instruction from storage system, at least one input device, and at least one output device, and transmit data and instruction to this storage system, this at least one input device, and this at least one output device an output device.

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 can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus, so that the computer program causes the functions/operations specified in the flowcharts and/or block diagrams to be implemented when executed by the processor. A computer program may execute entirely on the machine, partly on the machine, as a stand-alone software package partly on the machine and partly on a remote machine or entirely on the remote machine or server.

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, apparatus or device. A computer readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. Alternatively, a computer readable storage medium may be a machine readable signal medium. More specific examples of machine-readable storage media would include one or more wire-based electrical connections, portable computer discs, hard drives, random access memory (RAM), read only memory (ROM), erasable programmable read only memory (EPROM or flash memory), optical fiber, compact disk read only memory (CD-ROM), optical storage, magnetic storage, or any suitable combination of the foregoing.

In order to provide interaction with the user, the systems and techniques described herein can be implemented on an electronic device having a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display)) for displaying information to the user. monitor); and a keyboard and pointing device (eg, a mouse or a trackball) through which the user can provide input to the electronic device. Other kinds of devices can also be used to provide interaction with the user; for example, the feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and can be in any form (including Acoustic input, speech input or, tactile input) to receive input from the user.

The systems and techniques described herein can be implemented in a computing system that includes back-end 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 front-end components (e.g., as a a user computer having a graphical user interface or web browser through which a user can interact with embodiments of the systems and techniques described herein), or including such backend components, middleware components, Or any combination of front-end components in a computing system. The components of the system can be interconnected by any form or medium of digital data communication, eg, a communication network. Examples of communication networks include: local area networks (LANs), wide area networks (WANs), blockchain networks, and the Internet.

A computing system can include clients and servers. Clients and servers are generally remote from each other and typically interact through a communication network. The relationship of client and server arises by computer programs running on the respective computers and having a client-server relationship to each other. The server can be a cloud server, also known as a cloud computing server or a cloud host. It is a host product in the cloud computing service system to solve the problems of difficult management and weak business expansion in traditional physical hosts and VPS services. defect.

Note that the above are only preferred embodiments of the present invention and applied technical principles. 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, rearrangements and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and can also include more other equivalent embodiments without departing from the concept of the present invention, and the present invention The scope is determined by the scope of the appended claims.

Claims (10)

1. A cell sorting method, characterized in that, comprising: Acquiring the formation voltage record data, and determining the first voltage inflection point, the second voltage inflection point, and the formation end voltage in the formation voltage record data; determining a first voltage rise rate between the first voltage inflection point and the second voltage inflection point, and determining a second voltage rise rate between the second voltage inflection point and the formation end voltage; Obtaining the first open circuit voltage after the end of the first discharge stage, obtaining the second open circuit voltage after the end of the second discharge stage, and obtaining the third open circuit voltage after the end of the third discharge stage; determining the first open circuit voltage difference according to the first open circuit voltage and the second open circuit voltage, and determining the second open circuit voltage difference according to the second open circuit voltage and the third open circuit voltage; Cell sorting is performed according to the formation end voltage, the first voltage rise rate, the second voltage rise rate, the first open circuit voltage difference and the second open circuit voltage difference. 2. The cell sorting method according to claim 1, wherein the first voltage inflection point ranges from 1.8V to 2.2V; The range of the second voltage inflection point is 2.8V-3.2V; The range of the formation termination voltage is 3.6V-4.0V. 3 . The cell sorting method according to claim 1 , wherein the first discharge stage includes discharging the cell from the formation termination voltage to a set SOC value. 4 . 4 . The cell sorting method according to claim 1 , wherein the second discharge stage comprises the cell standing under the first temperature condition for a first period of time. 5 . 5 . The cell sorting method according to claim 1 , wherein the third discharge stage comprises cells standing under a second temperature condition for a second duration. 6. The cell sorting method according to claim 1, characterized in that, according to the formation termination voltage, the first voltage rise rate, the second voltage rise rate, the first open circuit voltage difference and the second open circuit voltage difference Cell sorting includes: The first sorting is performed according to the formation termination voltage, the second sorting is performed according to the first voltage rising rate and the second voltage rising rate, and the third sorting is performed according to the first open circuit voltage difference and the second open circuit voltage difference. 7. The cell sorting method according to claim 3, wherein the set SOC value is 2%-7% SOC. 8. A cell sorting device, characterized in that it includes a cell sorting unit, and the cell sorting unit is used for: Acquiring the formation voltage record data, and determining the first voltage inflection point, the second voltage inflection point, and the formation end voltage in the formation voltage record data; determining a first voltage rise rate between the first voltage inflection point and the second voltage inflection point, and determining a second voltage rise rate between the second voltage inflection point and the formation end voltage; Obtaining the first open circuit voltage after the end of the first discharge stage, obtaining the second open circuit voltage after the end of the second discharge stage, and obtaining the third open circuit voltage after the end of the third discharge stage; determining the first open circuit voltage difference according to the first open circuit voltage and the second open circuit voltage, and determining the second open circuit voltage difference according to the second open circuit voltage and the third open circuit voltage; Cell sorting is performed according to the formation end voltage, the first voltage rise rate, the second voltage rise rate, the first open circuit voltage difference and the second open circuit voltage difference. 9. An electronic device, 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, the computer program is executed by the at least one processor, so that the at least one processor can perform any one of claims 1-7 The cell sorting method. 10. 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 any one of claims 1-7 when executed. The cell sorting method described above.