Battery capacity determination method and battery state-of-health determination method

Abstract

A battery capacity determination method, comprising: (S1) when the initial static voltage of a battery from which charging starts is less than or equal to a preset voltage threshold value, on the basis of an initial residual capacity corresponding to the initial static voltage and a first capacity charged into the battery from the initial static voltage to a high-voltage inflection point, updating the high-voltage inflection point capacity of the battery to obtain the current high-voltage inflection point capacity of the battery; and (S2), on the basis of the current high-voltage inflection point capacity, determining the current maximum capacity of the battery.

Description

Method for determining battery capacity and method for determining battery health status

[0001] Priority information

[0002] This application claims priority and benefits of patent application No. 2023117384826 filed with the State Intellectual Property Office of China on December 15, 2023, and the entire text of which is incorporated herein by reference. Technical Field

[0003] The present invention relates to the field of new energy, and in particular to a battery capacity determination method, a battery health status determination method, a computer program product, a processor, a distribution box, a BMS system, and electric energy equipment. Background Art

[0004] With the rapid development of the automotive industry, new energy vehicles (NEVs) are gradually gaining popularity. Compared to traditional vehicles, NEVs, especially electric vehicles, emit fewer harmful substances. Electric vehicles are powered by batteries, which convert chemical energy into electricity to drive the motor that drives the vehicle. The battery's state of health (SOH) is a crucial parameter for measuring the safety, reliability, and performance of electric vehicles.

[0005] Related technologies typically calculate battery capacity by determining the high-voltage inflection point of the battery's charging curve from offline data. However, this point can change due to initial cell variations or cell aging. Consequently, using offline data to calculate battery capacity can result in significant errors.

[0006] Summary of the Invention

[0007] The present invention aims to solve at least one of the technical problems in the related art to a certain extent. To this end, one object of the present invention is to provide a method for determining battery capacity, which has the advantage of improving the accuracy of battery capacity.

[0008] According to a first aspect of an embodiment of the present invention, a method for determining battery capacity is provided, comprising:

[0009] When the initial quiescent voltage of the battery at the start of charging is less than or equal to a preset voltage threshold, updating the high-voltage inflection point capacity of the battery according to the initial remaining capacity corresponding to the initial quiescent voltage and the first capacity charged when the battery is charged from the initial quiescent voltage to the high-voltage inflection point, to obtain the current high-voltage inflection point capacity of the battery;

[0010] The current maximum capacity of the battery is determined according to the current high-voltage inflection point capacity.

[0011] In an exemplary embodiment of the present disclosure, updating the high-voltage inflection point capacity of the battery according to the initial remaining capacity corresponding to the initial static voltage and the first capacity charged when the battery is charged from the initial static voltage to the high-voltage inflection point includes:

[0012] Obtaining the initial remaining capacity;

[0013] Obtaining the previous maximum capacity of the battery;

[0014] The current high-voltage inflection point capacity is determined according to the previous maximum capacity, the initial remaining capacity, and the first capacity.

[0015] In an exemplary embodiment of the present disclosure, determining the current high-voltage inflection point capacity according to the previous maximum capacity, the initial remaining capacity, and the first capacity includes:

[0016] Calculating the product of the previous maximum capacity and the initial remaining capacity;

[0017] calculating a first sum of the product and the first capacity;

[0018] The first sum is used as the current high-voltage inflection point capacity.

[0019] In an exemplary embodiment of the present disclosure, determining the current maximum capacity of the battery according to the current high-voltage inflection point capacity includes:

[0020] Obtaining a second capacity of the battery when it is charged from a high voltage inflection point to full charge;

[0021] The current maximum capacity is determined according to the second capacity and the current high-voltage inflection point capacity.

[0022] In an exemplary embodiment of the present disclosure, the method further includes:

[0023] When the initial static voltage is greater than the preset voltage threshold, the current maximum capacity is determined according to the last high voltage inflection point capacity of the battery.

[0024] In an exemplary embodiment of the present disclosure, before updating the high-voltage inflection point capacity of the battery according to the initial remaining capacity corresponding to the initial static voltage and the first capacity charged when the battery is charged from the initial static voltage to the high-voltage inflection point, and obtaining the current high-voltage inflection point capacity of the battery, the method further includes:

[0025] Obtaining a voltage-capacity curve of the battery during a charging process;

[0026] Performing smoothing filtering on the voltage-capacity curve to obtain a filtered voltage-capacity curve;

[0027] performing a differential operation on the voltage-capacity curve to obtain a voltage-differential-capacity curve;

[0028] A peak value of the voltage differential capacity curve is obtained, and the high voltage inflection point is determined according to the peak value.

[0029] In an exemplary embodiment of the present disclosure, determining the high voltage inflection point according to the peak value includes:

[0030] acquiring a peak voltage corresponding to the peak value from the voltage-capacity curve;

[0031] Obtaining a maximum value of the peak voltage;

[0032] The maximum value is taken as the high voltage inflection point.

[0033] According to a second aspect of the present disclosure, a method for determining a battery health state is provided, which is applied to the capacity updating method described in any one of the first aspects, including:

[0034] Determine the current maximum capacity of the battery using the capacity updating method according to any one of the first aspects;

[0035] The health state of the battery is determined according to a ratio of the current maximum capacity to the initial capacity of the battery.

[0036] According to a third aspect of the present disclosure, a computer program product comprising instructions is provided. When the computer program product is run on the computer, the computer is caused to execute the battery capacity determination method as described in any one of the first aspects, or the battery health status determination method as described in the second aspect.

[0037] According to a fourth aspect of the present disclosure, a processor is provided, wherein the processor is configured to execute instructions to implement the battery capacity determination method as described in any one of the first aspects, or the battery health status determination method as described in the second aspect.

[0038] According to a fifth aspect of the present disclosure, a distribution box is provided, comprising the processor as described in the third aspect.

[0039] According to a sixth aspect of the present disclosure, a BMS system is provided, comprising the distribution box as described in the fifth aspect, and / or the processor as described in the fifth aspect.

[0040] According to a seventh aspect of the present disclosure, an electric energy device includes the BMS system as described in the sixth aspect.

[0041] The battery capacity determination method of an embodiment of the present invention, when the initial static voltage at the start of charging of the battery is less than or equal to a preset voltage threshold, updates the high voltage inflection point capacity of the battery according to the initial remaining capacity corresponding to the initial static voltage and the first capacity charged into the battery when charging from the initial static voltage to the high voltage inflection point, thereby obtaining the current high voltage inflection point capacity of the battery; determines the current maximum capacity of the battery according to the current high voltage inflection point capacity, thereby avoiding the problem of large errors in calculating the battery capacity based on the battery's offline data, thereby greatly improving the accuracy of the battery capacity.

[0042] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] FIG1 is a flow chart of a method for determining battery capacity according to an exemplary embodiment;

[0044] FIG2 is a schematic diagram of a voltage-capacity curve provided according to an exemplary embodiment;

[0045] FIG3 is a schematic diagram of a voltage differential capacity curve provided according to an exemplary embodiment;

[0046] FIG4 is a flow chart of a method for determining a battery health status according to an exemplary embodiment;

[0047] FIG5 is a schematic diagram of a computer program product provided according to an exemplary embodiment;

[0048] FIG6 is a block diagram of an electric energy device according to an exemplary embodiment. DETAILED DESCRIPTION

[0049] The following describes embodiments of the present invention in detail, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and are not to be construed as limiting the present invention.

[0050] The following describes a method for determining battery capacity according to an embodiment of the present invention with reference to the accompanying drawings. Referring to FIG1 , the method for determining battery capacity may include the following steps:

[0051] S1. When an initial quiescent voltage at the start of charging of a battery is less than or equal to a preset voltage threshold, updating the high-voltage inflection point capacity of the battery according to an initial remaining capacity corresponding to the initial quiescent voltage and a first capacity charged when the battery is charged from the initial quiescent voltage to a high-voltage inflection point, to obtain a current high-voltage inflection point capacity of the battery;

[0052] S2. Determine the current maximum capacity of the battery according to the current high-voltage inflection point capacity.

[0053] To summarize, the battery capacity determination method of an embodiment of the present invention is as follows: when the initial static voltage at the start of charging of the battery is less than or equal to a preset voltage threshold, the high voltage inflection point capacity of the battery is updated according to the initial remaining capacity corresponding to the initial static voltage and the first capacity charged when the battery is charged from the initial static voltage to the high voltage inflection point, so as to obtain the current high voltage inflection point capacity of the battery; and the current maximum capacity of the battery is determined according to the current high voltage inflection point capacity, thereby avoiding the problem of large errors in calculating the battery capacity based on the battery's offline data, thereby greatly improving the accuracy of the battery capacity.

[0054] Below, each step of the battery capacity determination method in this exemplary embodiment will be described in more detail with reference to the accompanying drawings and embodiments.

[0055] In step S1, when the initial static voltage at which the battery starts charging is less than or equal to a preset voltage threshold, the high voltage inflection point capacity of the battery is updated according to the initial remaining capacity corresponding to the initial static voltage and the first capacity charged when the battery is charged from the initial static voltage to the high voltage inflection point, to obtain the current high voltage inflection point capacity of the battery.

[0056] The following describes how to determine the first capacity charged into the battery when it is charged from the initial static voltage to the high voltage inflection point.

[0057] In an exemplary embodiment of the present disclosure, the battery may be a lithium-ion battery. The following describes an embodiment of the present disclosure using a lithium iron phosphate lithium-ion battery as an example.

[0058] In an exemplary embodiment of the present invention, after the lithium iron phosphate lithium-ion battery is discharged, the lithium iron phosphate lithium-ion battery can be left to stand for a period of time, for example, the lithium iron phosphate lithium-ion battery can be left to stand for two hours, and then the lithium iron phosphate lithium-ion battery can be charged and the initial static voltage of the lithium iron phosphate lithium-ion battery can be obtained.

[0059] In an exemplary embodiment of the present invention, if the measured static voltage of the lithium iron phosphate lithium-ion battery is smaller, the capacity of the lithium iron phosphate lithium-ion battery calculated based on the voltage at this time is closer to the actual capacity, that is, the capacity of the lithium iron phosphate lithium-ion battery is more accurate. Therefore, it is more accurate to obtain the first capacity charged into the lithium iron phosphate lithium-ion battery when it is charged from the current voltage to the high voltage inflection point, and then it is more accurate to update the current high voltage inflection point capacity of the battery based on the first capacity, thereby obtaining more accurate data. In an exemplary embodiment of the present invention, the charging time and charging current of the lithium iron phosphate lithium-ion battery when it is charged from the current voltage to the high voltage inflection point can be obtained, and then the ampere-hour integration is used to calculate the first capacity charged into the lithium iron phosphate lithium-ion battery when it is charged from the current voltage to the high voltage inflection point. The ampere-hour integration method is a basic method for battery power measurement, which uses the current-time accumulation method to perform real-time battery charge state estimation on dynamic lithium batteries. The calculation formula of the ampere-hour integration method is as follows:

[0060] Where SOC0 is the initial state of charge (SOC) value of the battery; CE is the rated capacity of the battery; I(t) is the charge and discharge current of the battery at time t; and t is the charge and discharge time. The ampere-hour integration method is relatively less restricted by the battery's inherent characteristics. Its calculation method is simple and reliable, and it can provide real-time estimation of the battery's SOC.

[0061] The following describes how to determine the high voltage inflection point of lithium iron phosphate lithium-ion batteries.

[0062] Based on the above, in an exemplary embodiment of the present invention, before updating the high-voltage inflection point capacity of the battery based on the initial remaining capacity corresponding to the initial quiescent voltage and the first capacity charged when the battery is charged from the initial quiescent voltage to the high-voltage inflection point, and obtaining the current high-voltage inflection point capacity of the battery, the method further includes:

[0063] S31, obtaining a voltage-capacity curve of the battery during the charging process;

[0064] S32, performing smoothing filtering on the voltage-capacity curve to obtain a filtered voltage-capacity curve;

[0065] S33, performing a differential operation on the filtered voltage-capacity curve to obtain a voltage-differential-capacity curve;

[0066] Generally speaking, the voltage-capacity curve of a lithium-ion battery during the charge and discharge process has a range where the voltage changes relatively slowly, called a voltage plateau. During the transition between two different plateaus, there is a point where the voltage changes most rapidly, called an inflection point. For lithium iron phosphate batteries, there are three such voltage plateaus, and therefore two inflection points, distinguished by voltage. The higher voltage inflection point is marked as the high voltage inflection point (HVTP), and the lower voltage inflection point is marked as the low voltage inflection point (LVTP).

[0067] In an exemplary embodiment of the present invention, the lithium iron phosphate lithium-ion battery can be discharged to a cut-off voltage (SOC = 0%) before leaving the factory, and then the lithium iron phosphate lithium-ion battery is charged, and the voltage-capacity curve of the lithium iron phosphate lithium-ion battery during the charging process is recorded. The recorded voltage-capacity curve is shown in Figure 2. Further, the voltage-capacity curve is smoothed and filtered to obtain a filtered voltage-capacity curve. The difference between the voltage and capacity of the filtered voltage-capacity curve is then calculated to obtain a voltage-differential capacity curve, such as shown in Figure 3.

[0068] S34. Obtain a peak value of the voltage differential capacity curve, and determine the high voltage inflection point according to the peak value.

[0069] In an exemplary embodiment of the present invention, a peak voltage corresponding to the peak value is obtained from the voltage-capacity curve; a maximum value of the peak voltage is obtained; and the maximum value is used as the high-voltage inflection point.

[0070] For example, as shown in Figure 3, there are two peaks obtained from the voltage differential capacity curve: point A on the left and point B on the right. The peak voltage corresponding to point B on the right in the voltage-capacity curve is greater than the peak voltage corresponding to point A on the left. Therefore, the peak voltage at point B is the high voltage inflection point (HVTP) of the battery, and the peak voltage at point A is the low voltage inflection point (LVTP) of the battery.

[0071] Based on the above, in an exemplary embodiment of the present invention, before updating the high-voltage inflection point capacity of the battery based on the initial remaining capacity corresponding to the initial quiescent voltage and the first capacity charged when the battery is charged from the initial quiescent voltage to the high-voltage inflection point, the method further includes:

[0072] S41. Obtain the initial remaining capacity.

[0073] In an exemplary embodiment of the present disclosure, a triggering static voltage correction (Relaxation Voltage Correction, RVC) can be used to obtain the initial residual capacity. Specifically, after obtaining the initial static voltage of the lithium iron phosphate lithium-ion battery, the initial residual capacity SOC corresponding to the initial static voltage is obtained by using the battery voltage and state of charge (SOC) correspondence table. low .

[0074] In another exemplary embodiment of the present disclosure, the initial remaining capacity SOC can also be obtained by using the Kalman filter method. low The Kalman filter method is a method of predicting the state of charge of the battery pack in real time under dynamic conditions by first building a circuit model of resistors and capacitors, and then inputting the real-time voltage value of the circuit model. Therefore, by inputting the initial static voltage into the circuit model, the initial remaining capacity SOC can be obtained. low Since the accuracy is higher when the voltage changes more obviously during the discharge process, the Kalman filter method can also accurately predict the SOC state when the voltage is below the low voltage inflection point, and the Kalman filter method can accurately obtain the initial remaining capacity SOC corresponding to the initial static voltage. low , so as to obtain the high voltage inflection point capacity more accurately.

[0075] S42: Obtain the previous maximum capacity of the battery.

[0076] In an exemplary embodiment of the present disclosure, the last maximum capacity Q of the acid iron lithium ion battery after the last update of the high voltage inflection point capacity is obtained. last .

[0077] S43: Determine the current high-voltage inflection point capacity according to the previous maximum capacity, the initial remaining capacity, and the first capacity.

[0078] Based on the above content, in an exemplary embodiment of the present disclosure, determining the current high-voltage inflection point capacity according to the previous maximum capacity, the initial remaining capacity, and the first capacity includes:

[0079] S431, calculating the product of the previous maximum capacity and the initial remaining capacity;

[0080] S432. Calculate a first sum of the product and the first capacity;

[0081] S433: Use the first sum as the current high-voltage inflection point capacity.

[0082] In an exemplary embodiment of the present disclosure, the current high voltage inflection point capacity may be calculated using the following formula:

[0083] Q HVTP =Q soc +SOC low *Q last (2);

[0084] Among them, Q HVTP Indicates the current high voltage inflection point capacity, Q soc Indicates the first capacity.

[0085] In step S2, the current maximum capacity of the battery is determined according to the current high-voltage inflection point capacity.

[0086] Based on the above content, in an exemplary embodiment of the present disclosure, determining the current maximum capacity of the battery according to the current high voltage inflection point capacity includes:

[0087] S21. Obtaining a second capacity of the battery when it is charged from a high voltage inflection point to full charge;

[0088] S22. Determine the current maximum capacity according to the second capacity and the current high-voltage inflection point capacity.

[0089] In an exemplary embodiment of the present disclosure, the current maximum capacity of the lithium iron phosphate lithium-ion battery can be calculated using the following formula:

[0090] Q max =Q HVTP +Q HVP (3);

[0091] Among them, Q max Indicates the current maximum capacity, Q HVP Indicates the second capacity.

[0092] Based on the above content, in an exemplary embodiment of the present disclosure, the method further includes:

[0093] S5. When the initial static voltage is greater than the preset voltage threshold, determining the current maximum capacity according to the last high voltage inflection point capacity of the battery.

[0094] In an exemplary embodiment of the present disclosure, when the current static voltage is greater than the preset voltage threshold, the last updated high voltage inflection point capacity Q is used. HVTP Substitute into formula (3) to calculate the current maximum capacity of the battery.

[0095] In summary, the disclosed battery capacity determination method can update the battery's high-voltage inflection point capacity and determine the battery's current maximum capacity based on the current high-voltage inflection point capacity. This avoids the large errors that can occur when calculating battery capacity using offline battery data, thereby significantly improving the accuracy of battery capacity.

[0096] The following describes a method for determining the battery health status according to an embodiment of the present invention with reference to FIG4 . As shown in FIG4 , the method for determining the battery health status may include the following steps:

[0097] S61. Determine the current maximum capacity of the battery using the above capacity update method;

[0098] S62: Determine the health status of the battery according to the ratio of the current maximum capacity to the initial capacity of the battery.

[0099] In an exemplary embodiment of the present disclosure, after the current maximum capacity of the battery is determined using the above-mentioned battery capacity determination method, the ratio of the current maximum capacity to the initial capacity of the battery is calculated, and the battery health status is determined based on the ratio.

[0100] In an exemplary embodiment of the present disclosure, the ratio can be converted into a rate, which is then used as a battery health parameter. In an exemplary embodiment of the present disclosure, when the ratio of the current maximum capacity to the initial capacity of the battery is less than or equal to a preset threshold, a prompt message is sent to prompt the user to replace or repair the battery.

[0101] In summary, the battery health status determination method provided by the present invention can update the high voltage inflection point capacity of the battery, determine the current maximum capacity of the battery based on the updated high voltage inflection point capacity, and then determine the battery health status based on the current maximum capacity of the battery, which can greatly improve the accuracy of the health status.

[0102] After introducing the battery capacity determination method and the battery health state determination method according to an exemplary embodiment of the present invention, the computer program product according to an exemplary embodiment of the present invention will be described with reference to FIG5 . The computer program product may be a computer program product comprising instructions, which, when the computer program product is run on a computer, enables the computer to execute the battery capacity determination method or the battery health state determination method as described above. Referring to FIG5 , a program product 500 for implementing the above method according to an embodiment of the present invention is described, which may adopt a portable compact disk read-only memory (CD ROM) and include program code, and may be run on a device, such as a personal computer. However, the program product of the present invention is not limited thereto, and in this document, a readable storage medium may be any tangible medium containing or storing a program that may be used by or in conjunction with an instruction execution system, apparatus, or device.

[0103] The program product may be implemented in any combination of one or more readable media. The readable medium may be a readable signal medium or a readable storage medium. The readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, or component, or any combination thereof. More specific examples (a non-exhaustive list) of readable storage media include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof.

[0104] A computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, which carries readable program code. Such propagated data signals may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A readable signal medium may also be any readable medium other than a readable storage medium that can transmit, propagate, or transfer a program for use by or in conjunction with an instruction execution system, apparatus, or device.

[0105] The program code that comprises on the readable medium can be transmitted with any suitable medium, includes but not limited to wireless, wired, optical cable, RF etc., or above-mentioned any suitable combination.Can write the program code that is used to carry out the operation of the present invention with any combination of one or more programming languages, described programming language comprises object-oriented programming language such as Java, C++ etc., also comprises conventional procedural programming language such as " C " language or similar programming language.Program code can be carried out completely on user computing device, partly on user computing device, partly on remote computing device, or carry out completely on remote computing device or server.In the situation relating to remote computing device, remote computing device can comprise local area network (LAN) or wide area network (WAN) by the network of any kind, is connected to user computing device, perhaps, can be connected to external computing device (for example, utilize Internet service provider to come by Internet connection).

[0106] After introducing the computer program product according to the exemplary embodiment of the present invention, the processor according to the exemplary embodiment of the present invention is described below. The processor can be configured to execute instructions to implement the above-described method for determining battery capacity or the above-described method for determining battery health status. In an exemplary embodiment of the present disclosure, the processor can be a chip, an MCU, an integrated circuit, or a terminal device.

[0107] After introducing the processor according to the exemplary embodiment of the present invention, the distribution box according to the exemplary embodiment of the present invention will be described. The distribution box includes the processor as described above, and the processor is arranged in the distribution box.

[0108] After introducing the distribution box according to an exemplary embodiment of the present invention, the following describes a battery management system (BMS) according to an exemplary embodiment of the present invention. The BMS includes the distribution box and / or the processor described above, which are disposed within the BMS.

[0109] After introducing the BMS system according to an exemplary embodiment of the present invention, an electric energy device according to an exemplary embodiment of the present invention will be described below with reference to FIG6 . The electric energy device includes the BMS system described above, which is disposed within the electric energy device. The electric energy device may be a new energy vehicle, aircraft, ship, energy storage cabinet, or the like.

[0110] The electric energy device 60 shown in FIG6 is merely an example and should not limit the functions and scope of use of the embodiments of the present invention.

[0111] As shown in FIG6 , the electrical energy device 60 is represented by a general-purpose computing device. The components of the electrical energy device 60 may include, but are not limited to, at least one processing unit 610, at least one storage unit 620, a bus 630 connecting various system components (including the storage unit 620 and the processing unit 610), and a display unit 640. The storage unit stores program code that can be executed by the processing unit 610, causing the processing unit 610 to perform the steps described in the "Exemplary Methods" section above according to various exemplary embodiments of the present invention. For example, the processing unit 610 may perform steps S1 and S2 as shown in FIG1 , or steps S61 and S62 as shown in FIG4 .

[0112] The storage unit 620 may include a volatile storage unit, such as a random access memory unit (RAM) 6201 and / or a cache memory unit 6202, and may further include a read-only memory unit (ROM) 6203. The storage unit 620 may also include a program / utility 6204 having a set (at least one) of program modules 6205. Such program modules 6205 include, but are not limited to, an operating system, one or more application programs, other program modules, and program data. Each of these examples or some combination thereof may include the implementation of a network environment.

[0113] The bus 630 may include a data bus, an address bus, and a control bus.

[0114] The power device 60 can also communicate with one or more external devices 70 (e.g., a keyboard, a pointing device, a Bluetooth device, etc.) via an input / output (I / O) interface 650. The power device 60 also includes a display unit 640 connected to the input / output (I / O) interface 650 for display. Furthermore, the power device 60 can communicate with one or more networks (e.g., a local area network (LAN), a wide area network (WAN), and / or a public network, such as the Internet) via a network adapter 660. As shown, the network adapter 660 communicates with other modules of the electronic device 60 via a bus 630. It should be understood that, although not shown in the figure, other hardware and / or software modules can be used in conjunction with the power device 60, including but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage systems.

[0115] Furthermore, although the operations of the method of the present invention are described in a particular order in the accompanying drawings, this does not require or imply that the operations must be performed in this particular order, or that all illustrated operations must be performed to achieve the desired results. Additionally or alternatively, some steps may be omitted, multiple steps may be combined into one step, and / or one step may be broken down into multiple steps.

[0116] Although the spirit and principles of the present invention have been described with reference to several specific embodiments, it should be understood that the present invention is not limited to the specific embodiments disclosed, and the division into various aspects does not mean that the features of these aspects cannot be combined to benefit. Such division is only for the convenience of expression. The present invention is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

1. A method for determining battery capacity, wherein: include: When the initial static voltage at which the battery starts to be charged is less than or equal to a preset voltage threshold, the high voltage inflection point capacity of the battery is updated according to the initial remaining capacity corresponding to the initial static voltage and the first capacity charged when the battery is charged from the initial static voltage to the high voltage inflection point, to obtain the current high voltage inflection point capacity of the battery; and The current maximum capacity of the battery is determined according to the current high voltage inflection point capacity.

2. The method according to claim 1, wherein: The updating of the high voltage inflection point capacity of the battery according to the initial remaining capacity corresponding to the initial static voltage and the first capacity charged when the battery is charged from the initial static voltage to the high voltage inflection point comprises: Obtaining the initial remaining capacity; Obtaining the last maximum capacity of the battery; and The current high voltage inflection point capacity is determined according to the previous maximum capacity, the initial remaining capacity and the first capacity.

3. The method according to claim 2, wherein: The determining the current high voltage inflection point capacity according to the previous maximum capacity, the initial remaining capacity and the first capacity comprises: Calculating the product of the previous maximum capacity and the initial remaining capacity; calculating a first sum of the product and the first capacity; and The first sum is used as the current high voltage inflection point capacity.

4. The method according to claim 1, wherein: Determining the current maximum capacity of the battery according to the current high voltage inflection point capacity includes: Obtaining a second capacity charged into the battery when the battery is charged from a high voltage inflection point to full charge; and The current maximum capacity is determined according to the second capacity and the current high voltage inflection point capacity.

5. The method according to claim 1, wherein: The method further comprises: When the initial static voltage is greater than the preset voltage threshold, the current maximum capacity is determined according to the last high voltage inflection point capacity of the battery.

6. The method according to claim 1, wherein: Before updating the high voltage inflection point capacity of the battery according to the initial remaining capacity corresponding to the initial static voltage and the first capacity charged when the battery is charged from the initial static voltage to the high voltage inflection point to obtain the current high voltage inflection point capacity of the battery, the method further includes: Obtaining a voltage-capacity curve of the battery during the charging process; Performing smoothing filtering on the voltage-capacity curve to obtain a filtered voltage-capacity curve; Performing a differential operation on the voltage-capacity curve to obtain a voltage-differential-capacity curve; and A peak value of the voltage differential capacity curve is obtained, and the high voltage inflection point is determined according to the peak value.

7. The method according to claim 6, wherein: Determining the high voltage inflection point according to the peak value comprises: acquiring a peak voltage corresponding to the peak value from the voltage-capacity curve; Obtaining a maximum value of the peak voltage; and The maximum value is taken as the high voltage inflection point.

8. A method for determining a battery health state, wherein: include: Determine the current maximum capacity of the battery by the capacity updating method according to any one of claims 1 to 7; The health state of the battery is determined according to a ratio of the current maximum capacity to an initial capacity of the battery.

9. A computer program product comprising instructions, wherein: When the computer program product is run on a computer, the computer is enabled to execute the battery capacity determination method according to any one of claims 1 to 7, or the battery health state determination method according to claim 8.

10. A processor, wherein: The processor is configured to execute instructions to implement the battery capacity determination method according to any one of claims 1 to 7, or the battery health status determination method according to claim 8.

11. A distribution box, wherein: Comprising the processor of claim 10.

12. A BMS system, wherein: Includes the distribution box as described in claim 11, and / or includes the processor as described in claim 10.

13. An electric energy device, wherein: Includes the BMS system described in claim 12.

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