Detection method and system for rapidly formulating ternary cell rapid charging strategy
Through cycle charging and discharging and charging stand-alone cycle pretreatment, the DC internal resistance curve is drawn, the lithium-ion charge state boundary is determined, and the fast charging strategy is formulated, which solves the accuracy and complexity of lithium-ion fast charging detection of lithium-ion batteries, and realizes the Efficient and accurate battery charging strategy formulation.
Patent Information
- Application Number
- CN202411305083.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-19
- Publication Date
- 2024-12-17
AI Technical Summary
The prior art is difficult to detect the boundary of lithium-ion batteries under fast charging conditions quickly and accurately, and traditional methods require the production of three-electrode batteries or are complex in operation, which has errors and damage risks.
By cyclic charging and discharging the ternary battery cell to be tested, the standard capacity is determined, and multiple sets of charging rate intervals are set based on the standard capacity for charging and static circulation pre-processing, drawing the DC internal resistance curve of different charge states, and determining the lithium-ion charge performance state boundaries, thus formulating fast charging strategies.
The measurement-based lithium-ion boundary determination of appropriate charging intervals and solutions is achieved, and the battery charging ability is fully utilized, and the battery abuse is avoided. The operation is simple and the results are accurate, reducing the cost of exploring the charging solution.
Smart Images
Figure CN119147980A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of lithium-ion batteries, and in particular to a detection method and system for quickly formulating a fast-charging strategy for a ternary battery cell. Background Art
[0002] With the popularity of new energy vehicles, people's early concerns about lithium battery safety and mileage have gradually eased, and then turned to the requirements of charging capacity, that is, to charge as much electricity as possible in the same time, or to charge the same amount of electricity in the shortest possible time. Translated into the test plan, it is to charge with a larger current, but it is necessary to avoid lithium plating on the negative electrode surface during charging (the phenomenon that lithium ions that should be embedded in the negative electrode graphite are not embedded but deposited on the surface during charging). There are many conditions for lithium plating to occur. Here we focus on the situation of fast charging and lithium plating. In order to maximize the charging capacity of the battery cell, people use a variety of detection methods to explore the boundary of battery cell charging and lithium plating. The three-electrode method-when charging, the positive electrode potential of the battery cell rises and the negative electrode potential decreases. When the negative electrode potential is close to 0V, lithium plating may occur. The reason why it may be said is that some of the lithium metals analyzed may generate lithium ions in subsequent reactions and embed back into the positive electrode. However, this method requires the production of a three-electrode battery. The results of the small soft-pack three-electrode battery are quite different from those of the finished battery, and the results obtained have a certain error. Alternatively, you can determine whether lithium deposition has occurred in the battery cell by disassembling it after full charging. This method is reliable but the operation is more complicated and is a destructive test. Summary of the invention
[0003] In view of the above problems, the present disclosure provides a detection method for quickly formulating a fast charging strategy for a ternary battery cell, the method comprising:
[0004] Perform cyclic charge and discharge on the ternary battery cell to be tested to determine the standard capacity of the ternary battery cell to be tested;
[0005] Based on the standard capacity, multiple groups of charging rate intervals are set to perform charging and static cycle pretreatment on the ternary battery cells to be tested to obtain test data;
[0006] According to the test data, curves of different charge states versus DC internal resistance are plotted to obtain the charge state boundary of the lithium deposition of the ternary battery cell to be tested;
[0007] Formulate a fast charging strategy based on the lithium plating charge state boundary of the ternary battery cell to be tested.
[0008] Preferably, the ternary battery cell to be tested is subjected to cyclic charge and discharge to determine the standard capacity of the ternary battery cell to be tested, including:
[0009] Perform a preset number of charge and discharge cycles on the ternary battery cell to be tested;
[0010] Obtain the capacity of each cycle of the ternary battery cell to be tested and obtain multiple sets of capacity data;
[0011] Calculate the average value of multiple sets of capacity data and determine the standard capacity of the ternary battery cell to be tested.
[0012] Preferably, before setting multiple groups of charging rate intervals based on the standard capacity, the method includes:
[0013] Set the pretreatment temperature.
[0014] Preferably, the ternary battery cell to be tested is subjected to charging and static cycle pretreatment, including:
[0015] The ternary battery cell to be tested is cyclically charged and left to rest at a constant current, and the DC internal resistance value is collected each time when the charging voltage meets the charging terminal voltage and the resting voltage meets the resting terminal voltage;
[0016] When the charging voltage reaches the upper limit voltage of the ternary battery cell to be tested, the cycle ends.
[0017] Preferably, the curves of different states of charge versus DC internal resistance are drawn according to the test data, including:
[0018] The calculation formula of the charge value is soc=charged power / Cs*100%;
[0019] The calculation formula of the DC internal resistance is R=(U1-U2) / (xCs)*1000;
[0020] Among them, R represents the DC internal resistance value; soc represents the charge value; Cs represents the standard capacity; U1 represents the charging end voltage; U2 represents the static end voltage; x represents the rate.
[0021] Preferably, the lithium deposition charge state boundary of the ternary battery cell to be tested includes:
[0022] The soc point where d(R) / d(soc) is less than 0 is determined based on the DC internal resistance curve at different states of charge.
[0023] The present disclosure also proposes a detection system for quickly formulating a fast charging strategy for a ternary battery cell, the detection system comprising:
[0024] A cycle module is used to perform cycle charge and discharge on the ternary battery cell to be tested and determine the standard capacity of the ternary battery cell to be tested;
[0025] A preprocessing module is used to set multiple groups of charging rate intervals based on standard capacity, perform charging static cycle preprocessing on the ternary battery cell to be tested, and obtain test data;
[0026] The lithium deposition module is used to draw curves of different charge states versus DC internal resistance according to the test data to obtain the lithium deposition charge state boundary of the ternary battery cell to be tested;
[0027] A formulation module is used to formulate a fast charging strategy based on the lithium plating charge state boundary of the ternary battery cell to be tested.
[0028] Preferably, the cycle module is used to perform cyclic charging and discharging on the ternary battery cell to be tested to determine the standard capacity of the ternary battery cell to be tested, including:
[0029] The cycle module is used to perform a preset number of charge and discharge cycles on the ternary battery cell to be tested;
[0030] Obtain the capacity of each cycle of the ternary battery cell to be tested and obtain multiple sets of capacity data;
[0031] Calculate the average value of multiple sets of capacity data and determine the standard capacity of the ternary battery cell to be tested.
[0032] Preferably, the pre-processing module is used to perform charging static cycle pre-processing on the ternary battery cell to be tested, including:
[0033] The ternary battery cell to be tested is cyclically charged and left to rest at a constant current, and the DC internal resistance value is collected each time when the charging voltage meets the charging terminal voltage and the resting voltage meets the resting terminal voltage;
[0034] When the charging voltage reaches the upper limit voltage of the ternary battery cell to be tested, the cycle ends.
[0035] Preferably, the lithium deposition module is used to detect the lithium deposition state of charge boundary of the ternary battery cell to be tested, and includes:
[0036] The lithium analysis module is used to determine the state of charge point where d(R) / d(soc) < 0 based on the DC internal resistance curve at different states of charge.
[0037] The present disclosure has the following beneficial effects:
[0038] (1) The present disclosure is based on a test method for achieving optimal charging by measuring the lithium plating boundary of a battery cell at different temperatures and rates, and then formulating a suitable charging interval and charging plan in combination with the requirements of charging temperature, charging interval, and charging time.
[0039] (2) The present invention formulates a suitable charging strategy based on the characteristics of lithium batteries through simple tests, which can not only fully utilize the charging capacity of the battery, but also effectively avoid battery abuse. The operation is simple and the results are accurate, which can effectively save the cost required to explore charging solutions.
[0040] Other features and advantages of the present disclosure will be described in the following description, and partly become apparent from the description, or be understood by implementing the present disclosure. The purpose and other advantages of the present disclosure can be realized and obtained by the structures indicated in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS
[0041] In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0042] Figure 1 A diagram showing a detection method for quickly formulating a ternary battery cell fast charging strategy in an embodiment of the present disclosure;
[0043] Figure 2 The soc-R curve diagram of the test sample in the embodiment of the present disclosure is shown;
[0044] Figure 3 A curve diagram showing the charging strategy ratio of 8-80% SOC of the test sample in the embodiment of the present disclosure is shown;
[0045] Figure 4 A diagram showing a detection system for quickly formulating a fast charging strategy for a ternary battery cell in an embodiment of the present disclosure is shown;
[0046] Figure 5 A diagram showing a detection device for quickly formulating a fast-charging strategy for ternary batteries in an embodiment of the present disclosure. DETAILED DESCRIPTION
[0047] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as being limited to the examples set forth herein; on the contrary, these embodiments are provided so that the present disclosure will be more comprehensive and complete, and the concepts of the example embodiments are fully conveyed to those skilled in the art. The described features, structures, or characteristics may be combined in one or more embodiments in any suitable manner. In the following description, many specific details are provided to provide a full understanding of the embodiments of the present disclosure. However, those skilled in the art will appreciate that the technical solutions of the present disclosure may be practiced while omitting one or more of the specific details, or other methods, components, devices, steps, etc. may be adopted. In other cases, known technical solutions are not shown or described in detail to avoid obscuring various aspects of the present disclosure.
[0048] In addition, the accompanying drawings are only schematic illustrations of the present disclosure and are not necessarily drawn to scale. The same reference numerals in the figures represent the same or similar parts, and thus their repeated description will be omitted. Some of the block diagrams shown in the accompanying drawings are functional entities and do not necessarily correspond to physically or logically independent entities. These functional entities can be implemented in software form, or implemented in one or more hardware units or integrated circuits, or implemented in different networks and / or processor devices and / or microcontroller devices.
[0049] The flowcharts shown in the accompanying drawings are only exemplary and do not necessarily include all the steps. For example, some steps may be decomposed, while some steps may be combined or partially combined, so the actual execution order may change according to the actual situation.
[0050] The terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein, for example.
[0051] In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or sub-modules is not necessarily limited to those steps or sub-modules explicitly listed, but may include other steps or sub-modules not explicitly listed or inherent to these processes, methods, products, or apparatuses.
[0052] like Figure 1 As shown, the present disclosure proposes a detection method for quickly formulating a fast charging strategy for a ternary battery cell, the method comprising:
[0053] Perform cyclic charge and discharge on the ternary battery cell to be tested to determine the standard capacity of the ternary battery cell to be tested;
[0054] Based on the standard capacity, multiple groups of charging rate intervals are set to perform charging and static cycle pretreatment on the ternary battery cells to be tested to obtain test data;
[0055] Draw the DC internal resistance curves of different charge states according to the test data to obtain the lithium deposition charge state boundary of the ternary battery cell to be tested;
[0056] Formulate a fast charging strategy based on the lithium plating charge state boundary of the ternary battery cell to be tested.
[0057] Specifically, the ternary battery cell to be tested is charged and discharged cyclically to determine the standard capacity of the ternary battery cell to be tested, including:
[0058] Perform a preset number of charge and discharge cycles on the ternary battery cell to be tested;
[0059] Obtain the capacity of each cycle of the ternary battery cell to be tested and obtain multiple sets of capacity data;
[0060] Calculate the average value of multiple sets of capacity data and determine the standard capacity of the ternary battery cell to be tested.
[0061] Specifically, before setting multiple groups of charging rate intervals based on standard capacity, the following steps are included:
[0062] Set the pretreatment temperature.
[0063] Specifically, the ternary battery cell to be tested is subjected to charging and static cycle pretreatment, including:
[0064] The ternary battery cell to be tested is cyclically charged and left to rest at a constant current, and the DC internal resistance value is collected each time when the charging voltage meets the charging terminal voltage and the resting voltage meets the resting terminal voltage;
[0065] When the charging voltage reaches the upper limit voltage of the ternary battery cell to be tested, the cycle ends.
[0066] Specifically, curves of different states of charge versus DC internal resistance are drawn based on the test data, including:
[0067] The calculation formula of the charge value is soc=charged power / Cs*100%;
[0068] The calculation formula of the DC internal resistance is R=(U1-U2) / (xCs)*1000;
[0069] Among them, R represents the DC internal resistance value; soc represents the charge value; Cs represents the standard capacity; U1 represents the charging end voltage; U2 represents the static end voltage; x represents the rate.
[0070] Specifically, the lithium deposition charge state boundary of the ternary battery to be tested includes:
[0071] The state of charge point where d(R) / d(soc) < 0 is determined based on the curves of different states of charge versus DC internal resistance.
[0072] This method specifically comprises the following steps:
[0073] Step 1: Perform three charge and discharge cycles of a certain ternary single cell at 25°C ± 2°C using C / 3, and take the average value as the standard capacity Cs;
[0074] Step 2, adjust the ambient temperature to T, and charge at different rates. In this step, the charging rate interval is set according to the actual needs of the battery cell, 1 / 3Cs, 1 / 2Cs, 1Cs. 1.2Cs, 1.4Cs, 1.5Cs, 2Cs, 2.5Cs, 3Cs, etc. The specific plan is: xCs constant current charging 2% Cs, standing for 8s, and cyclic charging and standing steps until the charging voltage reaches the upper limit voltage Vmax of normal use of the battery cell.
[0075] Step 3: By calculating the DC internal resistance corresponding to every 2% soc, the soc-R curve of DC internal resistance at different charge states is obtained, and according to d(R) / d(soc)<0, the lithium deposition soc boundary of the experimental sample at temperature T and xCs rate is obtained.
[0076] Step 4: Develop a suitable fast charging strategy based on product usage requirements and the battery cell's lithium-ion boundary soc.
[0077] In step 1, accurate calibration of the cell capacity is related to the adjustment of SOC and the confirmation of the SOC boundary of lithium deposition. This step requires that the capacity deviation of 3 cycles of constant capacity is less than 1%, deviation = (maximum value - average value) / average value * 100%, or deviation = (average value - minimum value) / average value * 100%.
[0078] In step 2, the charging test rate is set according to the actual demand of the battery cell. The detailed scheme of step 2 is as follows:
[0079] The battery cell starts with empty power, and is charged at a constant current of Cs / 3 to 2% Cs. The terminal voltage of the charge is taken as U1. It is left to stand for 8s, and the terminal voltage of the standstill is taken as U2. The charging and standing steps are repeated until the charging voltage reaches the upper limit voltage Vmax of the battery cell. The upper limit protection voltage Vmax must be set for each charging step to avoid overcharging.
[0080] In step 3, the calculation method of soc is: soc = charged power / Cs*100%, internal resistance calculation R = (U1-U2) / (xCs)*1000, and the soc-R curve is drawn according to the calculation results;
[0081] In step 3, the soc point where d(R) / d(soc) < 0 is found according to the curve, indicating lithium deposition at the corresponding soc.
[0082] In step 4, the fast charging strategy should be formulated in combination with the charging temperature, charging range, and charging time requirements, and charging should be performed below the lithium plating SOC boundary.
[0083] The present disclosure is also applicable to the formulation of fast charging strategies for aged batteries.
[0084] Example
[0085] 1) The embodiment adopts a rated capacity of 117Ah (2.8-4.25V) to test, firstly, charge and discharge for 3 cycles at 25°C to calibrate the standard capacity Cs of the battery;
[0086] 2) Charge 2% Cs (Ah) with 0.6 Cs (A), let stand for 8 seconds, cycle the charging and standing steps until the charging voltage reaches the upper limit voltage of 4.25V, let stand for 30 minutes, discharge to 2.8V, and let stand for 30 minutes;
[0087] 3) Repeat step 2) with 0.8Cs, 1.0Cs, 1.2Cs, 1.4Cs, 1.6Cs, 1.8Cs, 2.0Cs, 2.5Cs, 2.7Cs, and 3.0Cs, and process the test results, R = (U1-U2) / (xCs)*1000, and draw the soc-R curve according to the calculation results to obtain the lithium deposition soc boundary of the test cell;
[0088] 4) Based on the SOC boundary of the battery cell, the recommended charging strategy for the test sample is obtained at 8-80% SOC.
[0089] The test results are as follows:
[0090] Table 1 shows the R value after test data processing. Figure 2 is the corresponding soc-R curve, Table 2 is the lithium plating soc boundary of the test cell, and Table 3 is the 8~80% soc charging strategy and corresponding graph of the test sample Figure 3 .
[0091] Table 1
[0092]
[0093]
[0094]
[0095] Table 2
[0096]
[0097]
[0098] Table 3
[0099]
[0100] like Figure 4 As shown, the present disclosure also proposes a detection system for quickly formulating a fast charging strategy for a ternary battery cell, the detection system comprising:
[0101] A cycle module is used to perform cycle charge and discharge on the ternary battery cell to be tested and determine the standard capacity of the ternary battery cell to be tested;
[0102] A preprocessing module is used to set multiple groups of charging rate intervals based on standard capacity, perform charging static cycle preprocessing on the ternary battery cell to be tested, and obtain test data;
[0103] The lithium deposition module is used to draw curves of different charge states versus DC internal resistance according to the test data to obtain the lithium deposition charge state boundary of the ternary battery cell to be tested;
[0104] A formulation module is used to formulate a fast charging strategy based on the lithium plating charge state boundary of the ternary battery cell to be tested.
[0105] like Figure 5 As shown, corresponding to the detection method for quickly formulating a fast-charging strategy for ternary batteries provided above, the present disclosure also provides a detection device for quickly formulating a fast-charging strategy for ternary batteries. Since the embodiment of the device is similar to the above-mentioned method embodiment, the description is relatively simple. Please refer to the description of the above-mentioned method embodiment for relevant details. The device described below is only schematic. The device may include: a processor 1, a memory 2, a communication bus (i.e., the above-mentioned device bus) and a search engine, wherein the processor 1 and the memory 2 communicate with each other through the communication bus and communicate with the outside through the communication interface. The processor 1 can call the logic instructions in the memory 2 to execute the detection method for quickly formulating a fast-charging strategy for ternary batteries.
[0106] In addition, the logic instructions in the above-mentioned memory 2 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on such an understanding, the technical solution of the present disclosure is essentially or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present disclosure. The aforementioned storage medium includes: a storage chip, a U disk, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a disk or an optical disk, and other media that can store program codes.
[0107] On the other hand, an embodiment of the present disclosure further provides a processor-readable storage medium, on which a computer program 3 is stored. When the computer program 3 is executed by the processor 1, it is implemented to execute the detection method for quickly formulating a fast charging strategy for a ternary battery cell provided in the above-mentioned embodiments.
[0108] The processor-readable storage medium can be any available medium or data storage device that can be accessed by the processor 1, including but not limited to magnetic storage (such as floppy disks, hard disks, magnetic tapes, magneto-optical disks (MO), etc.), optical storage (such as CD, DVD, BD, HVD, etc.), and semiconductor storage (such as ROM, EPROM, EEPROM, non-volatile memory (NANDFLASH), solid-state drive (SSD)), etc.
[0109] Those skilled in the art should understand that although the present disclosure is described in detail with reference to the aforementioned embodiments, it is still possible to modify the technical solutions recorded in the aforementioned embodiments, or to make equivalent replacements for some of the technical features therein; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present disclosure.
Claims
1. A detection method for quickly formulating a fast charging strategy for a ternary battery cell, characterized in that: The method comprises: Perform cyclic charge and discharge on the ternary battery cell to be tested to determine the standard capacity of the ternary battery cell to be tested; Based on the standard capacity, multiple groups of charging rate intervals are set to perform charging and static cycle pretreatment on the ternary battery cells to be tested to obtain test data; Draw the DC internal resistance curves of different charge states according to the test data to obtain the lithium deposition charge state boundary of the ternary battery cell to be tested; Formulate a fast charging strategy based on the lithium plating charge state boundary of the ternary battery cell to be tested.
2. The detection method for quickly formulating a fast charging strategy for a ternary battery cell according to claim 1, characterized in that: Cycle charge and discharge the ternary battery cell to be tested to determine the standard capacity of the ternary battery cell to be tested, including: Perform a preset number of charge and discharge cycles on the ternary battery cell to be tested; Obtain the capacity of each cycle of the ternary battery cell to be tested and obtain multiple sets of capacity data; Calculate the average value of multiple sets of capacity data and determine the standard capacity of the ternary battery cell to be tested.
3. The detection method for quickly formulating a fast charging strategy for a ternary battery cell according to claim 1, characterized in that: Before setting multiple groups of charging rate intervals based on standard capacity, include: Set the pretreatment temperature.
4. The detection method for quickly formulating a ternary battery fast charging strategy according to claim 1, characterized in that: Perform charging and static cycle pretreatment on the ternary battery to be tested, including: The ternary battery cell to be tested is cyclically charged and left to rest at a constant current, and the DC internal resistance value is collected each time when the charging voltage meets the charging terminal voltage and the resting voltage meets the resting terminal voltage; When the charging voltage reaches the upper limit voltage of the ternary battery cell to be tested, the cycle ends.
5. The detection method for quickly formulating a ternary battery fast charging strategy according to claim 1, characterized in that: Draw the DC internal resistance curves of different charge states based on the test data, including: The calculation formula of the charge value is soc=charged power / Cs*100%; The calculation formula of the DC internal resistance is R=(U1-U2) / (xCs)*1000; Among them, R represents the DC internal resistance value; soc represents the charge value; Cs represents the standard capacity; U1 represents the charging end voltage; U2 represents the static end voltage; x represents the rate.
6. The detection method for quickly formulating a fast charging strategy for a ternary battery cell according to claim 1, characterized in that: The lithium plating charge state boundary of the ternary battery to be tested includes: The state of charge point where d(R) / d(soc) < 0 is determined based on the DC internal resistance curves of different states of charge.
7. A detection system for quickly formulating a fast charging strategy for ternary batteries, characterized in that: The detection system comprises: A cycle module is used to perform cycle charge and discharge on the ternary battery cell to be tested and determine the standard capacity of the ternary battery cell to be tested; A preprocessing module is used to set multiple groups of charging rate intervals based on standard capacity, perform charging static cycle preprocessing on the ternary battery cell to be tested, and obtain test data; The lithium deposition module is used to draw curves of different charge states versus DC internal resistance according to the test data to obtain the lithium deposition charge state boundary of the ternary battery cell to be tested; A formulation module is used to formulate a fast charging strategy based on the lithium plating charge state boundary of the ternary battery cell to be tested.
8. The detection system for quickly formulating a ternary battery fast charging strategy according to claim 7, characterized in that: The cycle module is used to perform cyclic charging and discharging of the ternary battery cell to be tested and determine the standard capacity of the ternary battery cell to be tested, including: The cycle module is used to perform a preset number of charge and discharge cycles on the ternary battery cell to be tested; Obtain the capacity of each cycle of the ternary battery cell to be tested and obtain multiple sets of capacity data; Calculate the average value of multiple sets of capacity data and determine the standard capacity of the ternary battery cell to be tested.
9. The detection system for quickly formulating a ternary battery fast charging strategy according to claim 7, characterized in that: The pre-processing module is used to perform charging and static cycle pre-processing on the ternary battery to be tested, including: The ternary battery cell to be tested is cyclically charged and left to rest at a constant current, and the DC internal resistance value is collected each time when the charging voltage meets the charging terminal voltage and the resting voltage meets the resting terminal voltage; When the charging voltage reaches the upper limit voltage of the ternary battery cell to be tested, the cycle ends.
10. The detection system for quickly formulating a ternary battery fast charging strategy according to claim 7, characterized in that: The lithium analysis module is used to analyze the charge state boundary of the ternary battery to be tested, including: The lithium analysis module is used to determine the state of charge point where d(R) / d(soc) < 0 based on the DC internal resistance curve at different states of charge.