Lithium ion battery cycle life test method and electronic equipment

Abstract

The invention discloses a lithium ion battery cycle life test method and electronic equipment. Comprising the steps that based on a preset fast and slow charging proportion, a fast charging mode and / or a slow charging mode are / is executed on a lithium ion battery, charging parameters of the lithium ion battery are acquired, and the charging parameters comprise a current SOC value; in a fast charging mode and / or a slow charging mode, when the current SOC value reaches a first preset SOC value and a second preset SOC value, respectively applying a preset current value for constant-current discharging for a first preset time; after the fast charging and / or slow charging is finished, standing for a second preset time, discharging to a preset SOC lower limit value at a preset charging rate, and standing for a third preset time; and recording the number of charging times, and when the number of charging times reaches a preset number of charging times, performing a cyclic discharge test on the lithium ion battery based on a preset test process. According to the technical scheme provided by the embodiment of the invention, the safety risk of high-SOC high-rate charging is reduced, and the cycle life of the battery is prolonged while the high charging rate is maintained.

Description

Technical Field

[0001] This invention relates to the field of battery testing technology, and in particular to a method and electronic device for testing the cycle life of lithium-ion batteries. Background Technology

[0002] Lithium-ion batteries, with their advantages of high energy density, long cycle life, no memory effect, and lightweight design, have been widely used in consumer electronics, electric vehicles, and energy storage systems. However, in electric vehicle scenarios, users still face significant range anxiety, with the core issues being insufficient battery power and low charging efficiency. While increasing the charging rate can alleviate this problem, in the high state of charge (SOC) range (>80%), the lithium intercalation capacity of the negative electrode graphite approaches saturation, easily leading to lithium ion precipitation. This not only causes loss of active lithium but also poses potential safety risks.

[0003] The current mainstream charging strategy for power batteries is segmented variable-rate charging: high-rate fast charging is used when the state of charge (SOC) is low, and low-rate slow charging is used when the SOC is high. While this method avoids the risks of fast charging at high SOC, it sacrifices overall energy replenishment efficiency. On the other hand, continuous high-rate charging, although it can meet the demand for rapid energy replenishment, will accelerate battery aging and damage cycle life. Summary of the Invention

[0004] To address the shortcomings of the prior art, this invention provides a method for testing the cycle life of lithium-ion batteries. By optimizing the depolarization control mechanism during the charging process, the battery service life can be extended while ensuring energy replenishment efficiency.

[0005] According to one aspect of the present invention, a method for testing the cycle life of a lithium-ion battery is provided, comprising:

[0006] S1. During the cycle test phase, based on the preset fast and slow charging ratio, fast charging mode and / or slow charging mode are executed on the lithium-ion battery, and the charging parameters of the lithium-ion battery are obtained, including the current SOC value.

[0007] S2. In fast charging mode and / or slow charging mode, when the current SOC value reaches the first preset SOC value and the second preset SOC value, a preset current value is applied for constant current discharge for a first preset time.

[0008] S3. After fast charging and / or slow charging is completed, let it stand for a second preset time, and discharge it to the preset SOC lower limit value at a preset charging rate, and let it stand for a third preset time.

[0009] S4. Repeat steps S1-S3 and record the number of charging cycles. When the number of charging cycles reaches the preset number of charging cycles, perform a cycle discharge test on the lithium-ion battery based on the preset test procedure.

[0010] Optionally, the charging parameters also include real-time temperature and current charging current; and before step S2, the following is also included:

[0011] In the fast charging mode, the charging rate of the lithium-ion battery is adjusted based on the real-time temperature and the current SOC value;

[0012] In the slow charging mode, when the current charging current is greater than a preset charging current threshold, the current is limited to the preset charging current threshold.

[0013] Optionally, when the number of charging cycles reaches a preset number of charging cycles, a cycle discharge test is performed on the lithium-ion battery based on a preset test procedure, including:

[0014] When the number of charging cycles reaches the preset number of charging cycles, discharge to the third preset SOC value at the preset charging rate, let stand for a fourth preset time, then discharge to the fourth preset SOC value at the preset charging rate, and let stand for the third preset time.

[0015] Optionally, a loop control and termination phase may be included after step S4;

[0016] The cycle control and termination phase includes:

[0017] Repeat steps S1-S4, and record the number of iterations.

[0018] After each cycle, the capacity and / or DC internal resistance are retested.

[0019] The cycle terminates when the number of cycles is greater than or equal to the preset target value, and / or when the capacity decays to the fifth preset SOC value.

[0020] Optionally, an initial calibration phase may be included before step S1;

[0021] The initial calibration phase includes:

[0022] The lithium-ion battery is subjected to operating condition testing to obtain its initial reference capacity and DC internal resistance.

[0023] Optionally, the operating condition test includes capacity calibration test and DC internal resistance test.

[0024] Optionally, the lithium-ion battery is subjected to operating condition testing to obtain its initial reference capacity and DC internal resistance, including:

[0025] At room temperature, the lithium-ion battery is subjected to three standard charge-discharge cycles, and the capacity of the last discharge cycle is taken as the initial reference capacity.

[0026] The DC internal resistance of lithium-ion batteries was tested at different charging rates to obtain DC internal resistance data for lithium-ion battery charging.

[0027] Optionally, after performing operating condition testing on the lithium-ion battery to obtain the initial reference capacity and DC internal resistance, the method further includes:

[0028] Discharge to the preset SOC lower limit at the preset charging rate, and then let it stand at room temperature until thermal equilibrium is reached.

[0029] Optionally, adjusting the charging rate of the lithium-ion battery based on real-time temperature and current SOC value includes:

[0030] When the real-time temperature rises and the current SOC value is between 80% and 100%, choose a low-rate charging;

[0031] When the real-time temperature decreases and the current SOC value is between 0% and 80%, select high-rate charging.

[0032] The high magnification rates include 1.3C, 2.5C, 3.0C, 4.0C, and 5.0C, and the low magnification rates include 0.4C, 0.6C, 0.8C, and 1.0C.

[0033] According to another aspect of the present invention, an electronic device is provided, the electronic device comprising:

[0034] At least one processor; and

[0035] A memory communicatively connected to the at least one processor; wherein,

[0036] The memory stores a computer program that can be executed by the at least one processor, which enables the at least one processor to perform the lithium-ion battery cycle life test method according to any embodiment of the present invention.

[0037] This invention provides a method for testing the cycle life of a lithium-ion battery, comprising: S1, during the cycle test phase, performing a fast charging mode and / or a slow charging mode on the lithium-ion battery based on a preset fast / slow charging ratio, and acquiring the charging parameters of the lithium-ion battery, including the current SOC value; S2, in the fast charging mode and / or slow charging mode, when the current SOC value reaches a first preset SOC value and a second preset SOC value, applying a preset current value for constant current discharge for a first preset time; S3, after the fast charging and / or slow charging ends, allowing the battery to stand for a second preset time, and discharging it to a preset lower SOC value at a preset charging rate, and then allowing it to stand for a third preset time; S4, repeating steps S1-S3 and recording the number of charging cycles, and when the number of charging cycles reaches a preset number of charging cycles, performing a cycle discharge test on the lithium-ion battery based on a preset test procedure. The technical solution provided by the embodiments of the present invention reduces the safety risk of high SOC (>80%) high-rate charging by applying pulse discharge to suppress polarization effect through a polarization suppression strategy at specific nodes, thereby improving battery cycle life while maintaining a high charging rate.

[0038] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 A flowchart of a lithium-ion battery cycle life test method provided in an embodiment of the present invention;

[0041] Figure 2 A flowchart of another lithium-ion battery cycle life testing method provided in an embodiment of the present invention;

[0042] Figure 3 A comparison chart of expansion force and capacity retention curves for a lithium-ion battery cycle life test method provided in an embodiment of the present invention;

[0043] Figure 4 A comparison chart of DCIR growth rate and capacity retention curves for a lithium-ion battery cycle life testing method provided in this embodiment of the invention;

[0044] Figure 5A comparison diagram of charging voltage curves for a lithium-ion battery cycle life test method provided in an embodiment of the present invention;

[0045] Figure 6 A comparison diagram of charging voltage curves for another lithium-ion battery cycle life testing method provided in this embodiment of the invention;

[0046] Figure 7 This is a schematic diagram of an electronic device for a lithium-ion battery cycle life testing method provided in an embodiment of the present invention. Detailed Implementation

[0047] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0048] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0049] Figure 1 This is a flowchart illustrating a lithium-ion battery cycle life testing method provided in an embodiment of the present invention. This embodiment is applicable to the high SOC and high-rate charging process of lithium-ion batteries. The method can be executed by a lithium-ion battery cycle life testing device, which can be implemented in hardware and / or software. This device can be configured in any electronic device with communication capabilities. See also... Figure 1 The method includes:

[0050] S1. During the cycle test phase, based on the preset fast and slow charging ratio, fast charging mode and / or slow charging mode are executed on the lithium-ion battery, and the charging parameters of the lithium-ion battery are obtained, including the current SOC value.

[0051] The cycle testing phase refers to a crucial testing stage before lithium-ion batteries leave the factory / during performance verification. Its core is to simulate the "charge-discharge cycle process" of the battery in actual use, observing whether the battery's capacity decay, charging efficiency, and safety stability meet standards through repeated cycles. The preset fast / slow charging ratio is a 2F1N protocol, i.e., fast charging:slow charging = 2:1; the current SOC value is calculated by dividing the charging capacity during fast charging by the rated capacity.

[0052] Specifically, during the cycle test phase, the 2F1N protocol is executed, i.e., fast charging: slow charging = 2:1, to fast charge and / or slow charge the lithium-ion battery, and the current SOC value of the lithium-ion battery is obtained during the charging process.

[0053] S2. In fast charging mode and / or slow charging mode, when the current SOC value reaches the first preset SOC value and the second preset SOC value, a preset current value is applied for constant current discharge for a first preset time.

[0054] The first preset SOC value, the second preset SOC value, the preset current value, and the first preset time can all be preset according to different battery types and testing requirements, combined with empirical values. For example, in fast charging mode and / or slow charging mode, when charging to 85% SOC and 90% SOC, a constant current discharge of 10A for 10s is applied respectively. This embodiment suppresses polarization effects by applying pulse discharge in the high SOC range (>80%), thereby improving battery cycle life while maintaining a high charging rate.

[0055] S3. After fast charging and / or slow charging is completed, let it stand for a second preset time, and discharge it to the preset SOC lower limit value at a preset charging rate, and then let it stand for a third preset time.

[0056] The second preset time, preset charging rate, preset SOC lower limit, and third preset time can all be preset according to different battery types and testing requirements, combined with empirical values. For example, after fast charging and / or slow charging are completed, the battery is left to stand for 10 minutes, then discharged at a 1C rate to 0% SOC, and left to stand for 60 minutes.

[0057] S4. Repeat steps S1-S3 and record the number of charging cycles. When the number of charging cycles reaches the preset number of charging cycles, perform a cycle discharge test on the lithium-ion battery based on the preset test procedure.

[0058] The preset number of charging cycles can be pre-set based on different battery types and testing requirements, combined with empirical values. The preset testing procedure can also be pre-set based on different battery types and testing requirements. For example, steps S1-S3 are repeated, and the number of charging cycles is recorded. When the number of charging cycles reaches 54, the battery is discharged at a 1C rate to 60% SOC, left to stand for 24 hours, and then discharged again at a 1C rate to 0% SOC, left to stand for 60 minutes. In this embodiment, the 24-hour deep rest period after every 54 cycles can release mechanical stress and reduce electrode structure fatigue.

[0059] This invention provides a method for testing the cycle life of a lithium-ion battery, comprising: S1, during the cycle test phase, performing a fast charging mode and / or a slow charging mode on the lithium-ion battery based on a preset fast / slow charging ratio, and acquiring the charging parameters of the lithium-ion battery, including the current SOC value; S2, in the fast charging mode and / or slow charging mode, when the current SOC value reaches a first preset SOC value and a second preset SOC value, applying a preset current value for constant current discharge for a first preset time; S3, after the fast charging and / or slow charging ends, allowing the battery to stand for a second preset time, and discharging it to a preset lower SOC value at a preset charging rate, and then allowing it to stand for a third preset time; S4, repeating steps S1-S3 and recording the number of charging cycles, and when the number of charging cycles reaches a preset number of charging cycles, performing a cycle discharge test on the lithium-ion battery based on a preset test procedure. The technical solution provided by the embodiments of the present invention reduces the safety risk of high SOC (>80%) high-rate charging by applying pulse discharge to suppress polarization effect through a polarization suppression strategy at specific nodes, thereby improving battery cycle life while maintaining a high charging rate.

[0060] Figure 2 This is a flowchart illustrating another method for testing the cycle life of a lithium-ion battery according to an embodiment of the present invention. This embodiment further refines the aforementioned embodiments. See also... Figure 2 The method includes:

[0061] S21. During the cycle test phase, based on the preset fast and slow charging ratio, fast charging mode and / or slow charging mode are executed on the lithium-ion battery, and the charging parameters of the lithium-ion battery are obtained, including the current SOC value, real-time temperature and current charging current.

[0062] The cycle testing phase refers to a crucial testing stage before lithium-ion batteries leave the factory / during performance verification. Its core is to simulate the "charge-discharge cycle process" of the battery in actual use, observing whether the battery's capacity decay, charging efficiency, and safety stability meet standards through repeated cycles. The preset fast-to-slow charging ratio is a 2F1N protocol, i.e., fast charging:slow charging = 2:1. Real-time temperature of the lithium-ion battery is obtained by attaching a temperature sensing wire to it, allowing for real-time monitoring of temperature changes during cell cycling. The current charging current of the lithium-ion battery is obtained through a current sensor. The current SOC value is calculated by dividing the charging capacity during fast charging by the rated capacity.

[0063] Specifically, during the cyclic testing phase, the 2F1N protocol is executed, i.e., fast charging: slow charging = 2:1, to perform fast charging and slow charging on the lithium-ion battery, and to obtain the real-time temperature, current charging current, and current SOC value of the lithium-ion battery during the charging process.

[0064] S22. In fast charging mode, the charging rate of the lithium-ion battery is adjusted based on the real-time temperature and the current SOC value.

[0065] Specifically, by attaching a temperature sensing wire to the lithium-ion battery, the real-time temperature of the lithium-ion battery is obtained to monitor the temperature change during the cell cycle; the current charging current of the lithium-ion battery is obtained through a current sensor; during the cycle test phase, the 2F1N protocol, i.e., fast charging: slow charging = 2:1, is executed to fast charge and slow charge the lithium-ion battery, and the real-time temperature and current charging current of the lithium-ion battery are obtained during the charging process.

[0066] Specifically, the charging rate of the lithium-ion battery is reduced when the temperature rises and increased when the temperature falls. Different SOC values ​​correspond to different charging rates, which are predetermined based on previous experience and verification. Thus, the charging rate of the lithium-ion battery is adjusted based on changes in the current SOC value—a higher rate is used for low SOC and a lower rate is used for high SOC.

[0067] S23. In slow charging mode, when the current charging current is greater than the preset charging current threshold, the current is limited to the preset charging current threshold.

[0068] The preset charging current threshold can be pre-set according to different lithium-ion battery models. For example, in slow charging mode, the current is limited to 250A when the charging current is greater than 250A.

[0069] S24. In fast charging mode and / or slow charging mode, when the current SOC value reaches the first preset SOC value and the second preset SOC value, a preset current value is applied for constant current discharge for a first preset time.

[0070] This step is the same as S2 in the above embodiment, and will not be described again here.

[0071] S25. After fast charging and / or slow charging is completed, let it stand for a second preset time, and discharge it to the preset SOC lower limit value at a preset charging rate, and then let it stand for a third preset time.

[0072] This step is the same as S3 in the above embodiment, and will not be described again here.

[0073] S26. Repeat steps S21-S25 and record the number of charging times. When the number of charging times reaches the preset number of charging times, discharge to the third preset SOC value at the preset charging rate, let stand for the fourth preset time, and then discharge to the fourth preset SOC value at the preset charging rate and let stand for the third preset time.

[0074] The third preset SOC value, the fourth preset time, and the fourth preset SOC value can all be preset according to different battery types and testing requirements, combined with empirical values. For example, steps S1-S5 are repeated, and the number of charging cycles is recorded. When the number of charging cycles reaches 54, the battery is discharged at a 1C rate to 60% SOC, left to stand for 24 hours, and then discharged at a 1C rate to 0% SOC, left to stand for 60 minutes. In this embodiment, the 24-hour deep rest period after every 54 cycles can release mechanical stress and reduce electrode structure fatigue.

[0075] The technical solution provided in this invention, during the cyclic testing phase, executes fast charging mode and slow charging mode on the lithium-ion battery based on a preset fast / slow charging ratio, and acquires the real-time temperature, current charging current, and current SOC value of the lithium-ion battery; in fast charging mode, adjusts the charging rate of the lithium-ion battery based on the real-time temperature and current SOC value; in slow charging mode, when the charging current exceeds a preset charging current threshold, the current is limited to the preset charging current threshold; in fast charging mode and / or slow charging mode, when charging to the first preset SOC value and the second preset SOC value, a preset current value is applied for constant current discharge for a first preset time; after fast charging and / or slow charging, the battery is left to stand for a second preset time, then discharged at a preset charging rate to the preset lower SOC value, and left to stand for a third preset time; the above steps are repeated, and the number of charging times is recorded; when the number of charging times reaches a preset number of charging times, the battery is discharged at a preset charging rate to the third preset SOC value, left to stand for a fourth preset time, and then discharged at a preset charging rate to the fourth preset SOC value, and left to stand for a third preset time. The technical solution provided by the embodiments of the present invention reduces the safety risk of high SOC (>80%) high-rate charging by applying pulse discharge to suppress polarization effect through a polarization suppression strategy at specific nodes, thereby improving battery cycle life while maintaining a high charging rate.

[0076] Optionally, a loop control and termination phase may be included after step S4; the loop control and termination phase includes:

[0077] Repeat steps S1-S4 and record the number of cycles. After each cycle, retest the capacity and / or DC internal resistance. Terminate when the number of cycles is greater than or equal to the preset target value and / or the capacity decays to the fifth preset SOC value.

[0078] The preset target value can be pre-set according to the cell performance requirements. The fifth preset SOC value can be pre-set according to different battery types and testing requirements, combined with empirical values. For example, steps S1-S6 are executed cyclically, and the number of cycles is recorded; after each cycle, the capacity and / or DC internal resistance are retested; the process terminates when the number of cycles is greater than or equal to the cell's State of Readiness (SOR) requirement value, and / or the capacity decays to 80%Q.

[0079] Optionally, an initial calibration stage may be included before step S1; the initial calibration stage includes:

[0080] The lithium-ion battery is subjected to operating condition testing to obtain its initial reference capacity and DC internal resistance.

[0081] The operating condition test includes capacity calibration test and DC internal resistance test.

[0082] Specifically, at room temperature, the lithium-ion battery is subjected to three standard charge-discharge cycles, and the capacity of the last discharge cycle is taken as the initial baseline capacity. At room temperature, the lithium-ion battery is tested for DC internal resistance at different charging rates to obtain the DC internal resistance (DCIR) data of the lithium-ion battery during charging, thereby determining the selected charging rate at different states of charge (SOC). The DCIR data includes DCIR values ​​at different charging rates and different SOCs.

[0083] Optionally, after performing operating condition testing on the lithium-ion battery to obtain the initial reference capacity and DC internal resistance, the method further includes:

[0084] Discharge to the preset SOC lower limit at the preset charging rate, and then let it stand at room temperature until thermal equilibrium is reached.

[0085] For example, discharge at a 1C rate to 0% SOC and then let stand at 25°C until thermal equilibrium is reached.

[0086] Optionally, adjusting the charging rate of the lithium-ion battery based on real-time temperature and current SOC value includes:

[0087] When the real-time temperature rises and the current SOC value is between 80% and 100%, select a low-rate charging; when the real-time temperature drops and the current SOC value is between 0% and 80%, select a high-rate charging. High rates include 1.3C, 2.5C, 3.0C, 4.0C, and 5.0C, while low rates include 0.4C, 0.6C, 0.8C, and 1.0C.

[0088] The following describes in detail the lithium-ion battery cycle life testing method provided by the present invention using a specific embodiment.

[0089] 1. Initial calibration stage

[0090] Let it rest at 25°C until it reaches thermal equilibrium;

[0091] Perform 3 standard charge-discharge cycles, and take the capacity of the last discharge cycle as the baseline capacity Q;

[0092] Measure the initial DC internal resistance;

[0093] Discharge at a 1C rate to the preset lower limit of SOC;

[0094] Let it rest at 25℃ until it reaches thermal equilibrium;

[0095] 2. Cyclic Testing Phase

[0096] Executes the 2F1N protocol (fast charging: slow charging = 2:1):

[0097] Fast charging mode: The charging rate is dynamically adjusted based on real-time temperature rise and SOC.

[0098] Slow charging mode: Current is limited to 250A when the current is >250A;

[0099] Polarization suppression: When charged to 85% SOC and 90% SOC, a constant current discharge of 10A is applied for 10s respectively;

[0100] Let it stand for 10 minutes after charging is complete;

[0101] Discharge at 1C rate to the lower limit of usable SOC, and let stand for 60 minutes;

[0102] After 48 charges:

[0103] Discharge at 1C to 60% SOC → Let stand for 24 hours → Discharge at 1C to the lower limit of SOC → Let stand for 60 minutes;

[0104] 3. Loop Control and Termination

[0105] Repeat step 2 for 24 cycles (including 16 fast charges + 8 slow charges).

[0106] Perform a capacity / DCIR retest after each cycle;

[0107] The cycle is terminated when the total number of cycles M is greater than or equal to the cell SOR requirement, or when the capacity decays to 80%Q.

[0108] Record the number of cycles - capacity / DCR / expansion force evolution data.

[0109] Using the above technical solution, the recorded cycle number-capacity / DCR / expansion force evolution data can be plotted as a curve. Figure 3 This is a comparison chart of expansion force and capacity retention curves for a lithium-ion battery cycle life testing method provided in an embodiment of the present invention. Figure 4 This is a comparison chart of DCIR growth rate and capacity retention rate curves for a lithium-ion battery cycle life testing method provided in this embodiment of the invention. Figure 5 This is a comparison chart of charging voltage curves for a lithium-ion battery cycle life testing method provided in an embodiment of the present invention. Figure 6 A comparison of charging voltage curves for another lithium-ion battery cycle life testing method provided in this embodiment of the invention. (See also...) Figure 3-6 The following table can be obtained.

[0110]

[0111] As can be seen from the above, the embodiments of the present invention significantly improve battery cycle life while maintaining a high charging rate through a polarization suppression strategy involving specific nodes, and synergistically optimize energy supply efficiency and long-term service performance.

[0112] According to another aspect of the present invention, an electronic device is provided, the electronic device comprising:

[0113] At least one processor; and a memory communicatively connected to the at least one processor; wherein,

[0114] The memory stores a computer program that can be executed by at least one processor, such that the at least one processor is able to execute the lithium-ion battery cycle life test method provided in any embodiment of the present invention.

[0115] According to another aspect of the present invention, a computer-readable storage medium is provided, which stores computer instructions for causing a processor to execute and implement the lithium-ion battery cycle life testing method provided in any embodiment of the present invention.

[0116] Figure 7This is a schematic diagram of an electronic device for a lithium-ion battery cycle life testing method provided in an embodiment of the present invention. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workbenches, 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 processors, cellular phones, smartphones, 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 illustrative and are not intended to limit the implementation of the invention described and / or claimed herein.

[0117] like Figure 7 As shown, the electronic device 10 includes at least one processor 11 and a memory, such as a read-only memory (ROM) 12 or a random access memory (RAM) 13, communicatively connected to the at least one processor 11. The memory stores computer programs executable by the at least one processor. The processor 11 can perform various appropriate actions and processes based on the computer program stored in the ROM 12 or loaded from storage unit 18 into the RAM 13. The RAM 13 can also store various programs and data required for the operation of the electronic device 10. The processor 11, ROM 12, and RAM 13 are interconnected via a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0118] Multiple components in electronic device 10 are connected to I / O interface 15, including: input unit 16, such as keyboard, mouse, etc.; output unit 17, such as various types of displays, speakers, etc.; storage unit 18, such as disk, optical disk, etc.; and communication unit 19, such as network card, modem, wireless transceiver, etc. Communication unit 19 allows electronic device 10 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0119] Processor 11 can be a variety of general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. Processor 11 performs the various methods and processes described above, such as a lithium-ion battery cycle life testing method.

[0120] In some embodiments, the lithium-ion battery cycle life testing method may be implemented as a computer program tangibly contained in a computer-readable storage medium, such as storage unit 18. In some embodiments, part or all of the computer program may be loaded and / or installed on electronic device 10 via ROM 12 and / or communication unit 19. When the computer program is loaded into RAM 13 and executed by processor 11, one or more steps of the lithium-ion battery cycle life testing method described above may be performed. Alternatively, in other embodiments, processor 11 may be configured to perform the lithium-ion battery cycle life testing method by any other suitable means (e.g., by means of firmware).

[0121] Various embodiments 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-a-chip (SoCs), payload-programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include implementations in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a dedicated or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transmitting data and instructions to the storage system, the at least one input device, and the at least one output device.

[0122] Computer programs used to implement 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, such that when executed by the processor, the computer programs cause the functions / operations specified in the flowcharts and / or block diagrams to be performed. The computer programs may be executed entirely on a machine, partially on a machine, or as a standalone software package, partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0123] In the context of this invention, a computer-readable storage medium can 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 thereof. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0124] To provide interaction with a 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) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user provides input to the electronic device. Other types of devices can also be used to provide interaction with the user; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including sound input, voice input, or tactile input).

[0125] The systems and technologies described herein can be implemented in computing systems that include backend components (e.g., as data servers), or computing systems that include middleware components (e.g., application servers), or computing systems that include frontend components (e.g., user computers with graphical user interfaces or web browsers through which users can interact with implementations of the systems and technologies described herein), or any combination of such backend, middleware, or frontend components. The components of the system can be interconnected via digital data communication of any form or medium (e.g., communication networks). Examples of communication networks include local area networks (LANs), wide area networks (WANs), blockchain networks, and the Internet.

[0126] A computing system can include clients and servers. Clients and servers are generally located far apart and typically interact through communication networks. The client-server relationship is created by computer programs running on the respective computers and having a client-server relationship with each other. The server can be a cloud server, also known as a cloud computing server or cloud host, which is a hosting product within the cloud computing service system to address the shortcomings of traditional physical hosts and VPS services, such as high management difficulty and weak business scalability.

[0127] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0128] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A method for testing the cycle life of a lithium-ion battery, characterized in that, include: S1. During the cycle test phase, based on the preset fast and slow charging ratio, fast charging mode and / or slow charging mode are executed on the lithium-ion battery, and the charging parameters of the lithium-ion battery are obtained, including the current SOC value. S2. In fast charging mode and / or slow charging mode, when the current SOC value reaches the first preset SOC value and the second preset SOC value, a preset current value is applied for constant current discharge for a first preset time. S3. After fast charging and / or slow charging is completed, let it stand for a second preset time, and discharge it to the preset SOC lower limit value at a preset charging rate, and let it stand for a third preset time. S4. Repeat steps S1-S3 and record the number of charging cycles. When the number of charging cycles reaches the preset number of charging cycles, perform a cycle discharge test on the lithium-ion battery based on the preset test procedure.

2. The lithium-ion battery cycle life testing method according to claim 1, characterized in that, The charging parameters also include real-time temperature and current charging current; The steps preceding step S2 also include: In the fast charging mode, the charging rate of the lithium-ion battery is adjusted based on the real-time temperature and the current SOC value; In the slow charging mode, when the current charging current is greater than a preset charging current threshold, the current is limited to the preset charging current threshold.

3. The lithium-ion battery cycle life testing method according to claim 1, characterized in that, When the number of charging cycles reaches the preset number of charging cycles, a cycle discharge test is performed on the lithium-ion battery based on a preset test procedure, including: When the number of charging cycles reaches the preset number of charging cycles, discharge to the third preset SOC value at the preset charging rate, let stand for a fourth preset time, then discharge to the fourth preset SOC value at the preset charging rate, and let stand for the third preset time.

4. The lithium-ion battery cycle life test method according to claim 2, characterized in that, The loop control and termination phase is also included after step S4; The cycle control and termination phase includes: Repeat steps S1-S4, and record the number of iterations. After each cycle, the capacity and / or DC internal resistance are retested. The cycle terminates when the number of cycles is greater than or equal to the preset target value, and / or when the capacity decays to the fifth preset SOC value.

5. The lithium-ion battery cycle life test method according to claim 1, characterized in that, The initial calibration phase is included before step S1; The initial calibration phase includes: The lithium-ion battery is subjected to operating condition testing to obtain its initial reference capacity and DC internal resistance.

6. The lithium-ion battery cycle life test method according to claim 5, characterized in that, The operating condition test includes capacity calibration test and DC internal resistance test.

7. The lithium-ion battery cycle life test method according to claim 5, characterized in that, The lithium-ion battery is subjected to operating condition testing to obtain its initial reference capacity and DC internal resistance, including: At room temperature, the lithium-ion battery is subjected to three standard charge-discharge cycles, and the capacity of the last discharge cycle is taken as the initial reference capacity. The DC internal resistance of lithium-ion batteries was tested at different charging rates to obtain DC internal resistance data for lithium-ion battery charging.

8. The lithium-ion battery cycle life test method according to claim 5, characterized in that, After performing operating condition tests on the lithium-ion battery to obtain its initial reference capacity and DC internal resistance, the following steps are also included: Discharge to the preset SOC lower limit at the preset charging rate, and then let it stand at room temperature until thermal equilibrium is reached.

9. The lithium-ion battery cycle life test method according to claim 2, characterized in that, Adjusting the charging rate of lithium-ion batteries based on real-time temperature and current SOC value includes: When the real-time temperature rises and the current SOC value is between 80% and 100%, choose a low-rate charging; When the real-time temperature decreases and the current SOC value is between 0% and 80%, select high-rate charging. The high magnification rates include 1.3C, 2.5C, 3.0C, 4.0C, and 5.0C, and the low magnification rates include 0.4C, 0.6C, 0.8C, and 1.0C.

10. An electronic device, characterized in that, The electronic device includes: At least one processor; and A memory communicatively connected to the at least one processor; wherein, The memory stores a computer program that can be executed by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform the lithium-ion battery cycle life test method according to any one of claims 1-9.

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