Method, device and equipment for determining hidden energy of electrochemical energy storage system and medium

Abstract

The invention relates to the technical field of electrochemical energy storage, and discloses a hidden energy determination method, device, equipment and medium for an electrochemical energy storage system, and the method comprises the steps: determining first theoretical maximum rated energy according to a rated charge-discharge voltage range when the operation state of the electrochemical energy storage system is an initial state, the first theoretical maximum rated energy is theoretical maximum rated energy of the electrochemical energy storage system in an initial state; according to the working charge-discharge voltage range, first actual rated discharge energy is determined, and the first actual rated discharge energy is rated discharge energy of the electrochemical energy storage system in the initial state; according to the first theoretical maximum rated energy and the first actual rated discharge energy, first hidden energy is determined, and the first hidden energy is hidden energy of the electrochemical energy storage system in the initial state. The hidden energy of the electrochemical system can be quantitatively evaluated according to the operation state of the electrochemical energy storage system, and energy loss and economic loss are reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electrochemical energy storage, and in particular to a hidden energy determination method, device, equipment and medium of an electrochemical energy storage system. BACKGROUND

[0002] Electrochemical energy storage represented by lithium-ion batteries and sodium-ion batteries is currently the main new energy storage method, and its installed capacity has exceeded pumped storage, becoming one of the most important flexible resources and playing an important role in the construction of new power systems.

[0003] An electrochemical energy storage system is composed of a large number of battery cells. Due to the inconsistency of the battery cells to some extent, the wood barrel effect will cause the total capacity of the energy storage system to be limited by the weakest link, and considering the battery degradation characteristics, the general manufacturer will over-provision the capacity of the electrochemical energy storage system, that is, the battery operating voltage interval will be narrowed. These two factors will cause a considerable part of the energy of the energy storage system to be hidden. At present, it is difficult to determine this part of the energy loss, which makes it difficult for the operation and maintenance personnel to evaluate the indirect energy loss caused by the hidden energy not being used. SUMMARY

[0004] Therefore, the present application provides a hidden energy determination method, device, equipment and medium of an electrochemical energy storage system to solve the problem of difficulty in evaluating the hidden energy of the electrochemical energy storage system.

[0005] In a first aspect, the present application provides a hidden energy determination method of an electrochemical energy storage system. The method comprises: in the case that the operating state of the electrochemical energy storage system is an initial state, determining a first theoretical maximum rated energy according to a rated charge and discharge voltage range, wherein the first theoretical maximum rated energy is the theoretical maximum rated energy of the electrochemical energy storage system in the initial state; determining a first actual rated discharge energy according to a working charge and discharge voltage range, wherein the first actual rated discharge energy is the rated discharge energy of the electrochemical energy storage system in the initial state; and determining a first hidden energy according to the first theoretical maximum rated energy and the first actual rated discharge energy, wherein the first hidden energy is the hidden energy of the electrochemical energy storage system in the initial state.

[0006] The present application quantitatively evaluates the hidden energy of the electrochemical energy storage system due to the inconsistency of the battery cells and the narrowing of the voltage interval according to the operating state of the electrochemical energy storage system, which helps the operation and maintenance personnel to contact the manufacturer in time for battery power supply processing and charge and discharge cutoff voltage parameter optimization, thereby reducing the energy and economic benefit loss caused by the inconsistency of the battery and the non-timely relaxation of the charge and discharge cutoff voltage.

[0007] In one optional implementation, the first hidden energy includes a first sub-hidden energy and a second sub-hidden energy. The first sub-hidden energy is the hidden energy generated by the over-provisioning of the electrochemical energy storage system in its initial state, and the second sub-hidden energy is the hidden energy generated by the inconsistency of the battery cells in the initial state. The method further includes: determining a first theoretical maximum energy based on the operating charge and discharge voltage range; determining the first hidden energy based on the first theoretical maximum rated energy and the first actual rated discharge energy, including: determining the first sub-hidden energy based on the difference between the first theoretical maximum rated energy and the first theoretical maximum energy; and determining the second sub-hidden energy based on the difference between the first theoretical maximum energy and the first actual rated discharge energy.

[0008] In one optional implementation, determining the first theoretical maximum energy based on the operating charge-discharge voltage range includes: determining the first theoretical rated discharge energy based on the operating charge-discharge voltage range and the initial cell charge-discharge curve; and determining the first theoretical maximum energy based on the first theoretical rated discharge energy and the number of cells in the electrochemical energy storage system.

[0009] In one alternative implementation, after determining the first hidden energy, the method further includes: determining the proportion of the first hidden energy, the proportion of the first sub-hidden energy, and the proportion of the second sub-hidden energy.

[0010] In an optional embodiment, the method further includes: determining a second theoretical maximum rated energy based on the rated charge / discharge voltage range after multiple cycles of operation of the electrochemical energy storage system, wherein the second theoretical maximum rated energy is the theoretical maximum rated energy of the electrochemical energy storage system after multiple cycles; determining a second actual rated discharge energy based on the operating charge / discharge voltage range, wherein the second actual rated discharge energy is the rated discharge energy of the electrochemical energy storage system after multiple cycles; and determining a second hidden energy based on the second theoretical maximum rated energy and the second actual rated discharge energy, wherein the second hidden energy is the hidden energy of the electrochemical energy storage system after multiple cycles.

[0011] In this embodiment, the second hidden energy is determined by the second theoretical maximum rated energy and the second actual rated discharge energy. This establishes a relationship between the number of cycles and the hidden energy, enabling the electrochemical energy storage system to quantitatively assess the hidden energy due to cell inconsistency and narrowing voltage range during operation. This makes it easier for maintenance personnel to contact the manufacturer for timely battery charging and to optimize charge / discharge cutoff voltage parameters.

[0012] In one optional implementation, the second hidden energy includes a third sub-hidden energy and a fourth sub-hidden energy. The third sub-hidden energy is the hidden energy generated by the over-provisioning of the electrochemical energy storage system after multiple cycles, and the fourth sub-hidden energy is the hidden energy generated by the inconsistency of the battery cells after multiple cycles. The method further includes: determining a second theoretical maximum energy based on the operating charge and discharge voltage range; determining the second hidden energy based on the second theoretical maximum rated energy and the second actual rated discharge energy, including: determining the third sub-hidden energy based on the difference between the second theoretical maximum rated energy and the second theoretical maximum energy; and determining the fourth sub-hidden energy based on the difference between the second theoretical maximum energy and the second actual rated discharge energy.

[0013] In one alternative implementation, after determining the second hidden energy, the method further includes: determining the proportion of the second hidden energy, the proportion of the third sub-hidden energy, and the proportion of the fourth sub-hidden energy.

[0014] Secondly, the present invention provides a hidden energy determination device for an electrochemical energy storage system. The device includes: a theoretical energy determination module, used to determine a first theoretical maximum rated energy based on a first rated charge-discharge voltage range when the electrochemical energy storage system is in its initial operating state; an actual energy determination module, used to determine a first actual rated discharge energy based on a working charge-discharge voltage range; and a hidden energy determination module, used to determine a first hidden energy based on the first theoretical maximum rated energy and the first actual rated discharge energy; and a hidden energy determination module, used to determine a first hidden energy based on the first theoretical maximum rated energy and the first actual rated discharge energy; and a hidden energy determination module, used to determine the hidden energy of the electrochemical energy storage system in its initial state.

[0015] In one optional embodiment, the apparatus further includes: a maximum energy determination module, configured to determine a first theoretical maximum energy based on the operating charge-discharge voltage range; and a hidden energy determination module, comprising: a first determination unit, configured to determine a first sub-hidden energy based on the difference between the first theoretical maximum rated energy and the first theoretical maximum energy; and a second determination unit, configured to determine a second sub-hidden energy based on the difference between the first theoretical maximum energy and the first actual rated discharge energy.

[0016] In one optional implementation, the first determining unit includes: a first determining subunit, configured to determine a first theoretical rated discharge energy based on the operating charge-discharge voltage range and the initial cell charge-discharge curve; and a second determining subunit, configured to determine a first theoretical maximum energy based on the first theoretical rated discharge energy and the number of cells in the electrochemical energy storage system.

[0017] In one optional embodiment, the apparatus further includes: a first proportion determination module, configured to determine the proportion of the first hidden energy, the proportion of the first sub-hidden energy, and the proportion of the second sub-hidden energy.

[0018] In one optional embodiment, the device further includes: a first determining module, configured to determine a second theoretical maximum rated energy based on the rated charge-discharge voltage range when the electrochemical energy storage system has been in operation for multiple cycles, wherein the second theoretical maximum rated energy is the theoretical maximum rated energy of the electrochemical energy storage system after multiple cycles; a second determining module, configured to determine a second actual rated discharge energy based on the operating charge-discharge voltage range, wherein the second actual rated discharge energy is the rated discharge energy of the electrochemical energy storage system after multiple cycles; and a third determining module, configured to determine a second hidden energy based on the second theoretical maximum rated energy and the second actual rated discharge energy, wherein the second hidden energy is the hidden energy of the electrochemical energy storage system after multiple cycles.

[0019] In an optional embodiment, the apparatus further includes: a fourth determining module, configured to determine a second theoretical maximum energy based on the operating charge-discharge voltage range; the third determining module includes: a third determining unit, configured to determine a third sub-hidden energy based on the difference between the second theoretical maximum rated energy and the second theoretical maximum energy; and a fourth determining unit, configured to determine a fourth sub-hidden energy based on the difference between the second theoretical maximum energy and the second actual rated discharge energy.

[0020] In one optional embodiment, the apparatus further includes: a second proportion determination module, used to determine the proportion of the second hidden energy, the proportion of the third sub-hidden energy, and the proportion of the fourth sub-hidden energy.

[0021] Thirdly, the present invention provides a computer device, comprising: a memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, and the processor executing the computer instructions to perform the method for determining the hidden energy of the electrochemical energy storage system described in the first aspect or any corresponding embodiment thereof.

[0022] Fourthly, the present invention provides a computer-readable storage medium storing computer instructions for causing a computer to execute the hidden energy determination method of the electrochemical energy storage system described in the first aspect or any corresponding embodiment thereof.

[0023] Fifthly, the present invention provides a computer program product, including computer instructions for causing a computer to execute the method for determining the hidden energy of an electrochemical energy storage system according to the first aspect or any corresponding embodiment thereof. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the specific embodiments or related technologies of the present invention, the drawings used in the description of the specific embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0025] Figure 1 This is a flowchart illustrating a method for determining the hidden energy of an electrochemical energy storage system according to an embodiment of the present invention.

[0026] Figure 2 This is a flowchart illustrating another method for determining the hidden energy of an electrochemical energy storage system according to an embodiment of the present invention;

[0027] Figure 3 This is a flowchart illustrating another method for determining the hidden energy of an electrochemical energy storage system according to an embodiment of the present invention;

[0028] Figure 4 This is a structural block diagram of a hidden energy determination device for an electrochemical energy storage system according to an embodiment of the present invention;

[0029] Figure 5 This is a schematic diagram of the hardware structure of a computer device according to an embodiment of the present invention. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0031] This invention provides a method, apparatus, equipment, and medium for determining the hidden energy of an electrochemical energy storage system. It can quantitatively assess the hidden energy of an electrochemical energy storage system based on its operating status, thereby reducing energy loss and economic losses.

[0032] The method for determining the hidden energy of an electrochemical energy storage system provided by the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowcharts, in some cases the steps shown or described may be performed in a different order than that shown here.

[0033] This invention provides a method for determining the hidden energy of an electrochemical energy storage system, which can be used in a device for determining the hidden energy of an electrochemical energy storage system. This device can be a terminal device such as a tablet computer or a computer, or it can be a functional module within a terminal device. Figure 1 This is a flowchart illustrating a method for determining the hidden energy of an electrochemical energy storage system according to an embodiment of the present invention, as shown below. Figure 1 As shown, the method includes the following steps:

[0034] Step S101: Under the condition that the electrochemical energy storage system is in its initial operating state, determine the first theoretical maximum rated energy based on the rated charge and discharge voltage range.

[0035] Among them, the first theoretical maximum rated energy is the theoretical maximum rated energy of the electrochemical energy storage system in the initial state.

[0036] The initial state refers to a baseline, traceable static state of an electrochemical energy storage system before it is installed, commissioned, and put into operation. In the initial state, the State of Health (SOH) of the electrochemical energy storage system can be 100% or close to 100% (e.g., 99%).

[0037] Electrochemical energy storage systems can consist of multiple battery clusters connected in parallel. Each battery cluster has relatively independent electrical characteristics and a management unit, allowing for individual monitoring of voltage, current, temperature, and other status parameters. Simultaneously, each battery cluster is equipped with a Power Conversion System (PCS), which controls the charging and discharging of the battery cluster. This allows each battery cluster to operate or stop independently, improving the flexibility and reliability of the electrochemical energy storage system.

[0038] Each battery cluster can be composed of multiple cells connected in series or parallel (such as the cells of a lithium battery). The cell is the smallest electrical energy storage unit in an energy storage system and is the core component for realizing the mutual conversion of chemical energy and electrical energy.

[0039] Assume the electrochemical energy storage system comprises N battery clusters, each cluster contains M cells, and the rated charge / discharge voltage range of each cell is V. clow ~V chigh When the battery cell is charged and discharged at the rated power P within the rated charge and discharge voltage range, the rated discharge energy of the battery cell in the initial state is E. c0 Then, the theoretical maximum rated energy (i.e. the first theoretical maximum rated energy) of the electrochemical energy storage system in the initial state can be determined by the following formula (1).

[0040] E s0 =N×M×E c0 (1)

[0041] In formula (1), E s0 The first theoretical maximum rated energy is represented by N; N represents the number of battery clusters, where N is an integer greater than or equal to 1; M represents the number of cells in each battery cluster, where M is also an integer greater than or equal to 1.

[0042] For example, the E corresponding to the rated charge / discharge voltage range can be obtained from the product specification sheet of the battery cell manufacturer. c0 Alternatively, charge-discharge experiments can be conducted using battery testing equipment to establish the rated charge-discharge voltage range and E. c0 The corresponding relationship is used to obtain E after determining the rated charge / discharge voltage range. c0 .

[0043] V clow This indicates the rated discharge cutoff voltage, which is the lowest voltage the cell is allowed to drop to during discharge; V chigh This indicates the rated charging cutoff voltage, which is the highest voltage that the battery cell is allowed to reach during the charging process.

[0044] Step S102: Determine the first actual rated discharge energy based on the working charge and discharge voltage range.

[0045] The first actual rated discharge energy is the rated discharge energy of the electrochemical energy storage system in its initial state.

[0046] Specifically, before the construction of an electrochemical energy storage system, the electrochemical energy storage system has design values ​​for charging and discharging parameters, such as a designed rated discharge energy of E. sd Rated power is P sd The rated charge / discharge range of the battery cell is V. low ~V high However, to address various risks, energy storage manufacturers typically over-produce cells, exceeding the designed rated charge / discharge range (V). low ~V hig If the system is charged and discharged too frequently, the capacity of the electrochemical energy storage system will be significantly higher than the design capacity. To avoid this problem, during the commissioning phase, the charging and discharging voltage range is typically narrowed to control the rated discharge energy to be slightly higher than the design capacity.

[0047] Assuming the actual operating charge / discharge voltage range after debugging is V 0low ~V 0high Within the operating charge / discharge voltage range, charging and discharging at rated power, the rated discharge energy (i.e., the first actual rated discharge energy) of the electrochemical energy storage system in its initial state is E. sd0 .

[0048] Specifically, it can be based on the operating charge / discharge voltage range (V) determined after debugging. 0low ~V 0highCharge-discharge experiments were conducted on the rated power and the operating voltage range to obtain a table showing the correspondence between different operating charge-discharge voltage ranges and the first actual rated discharge energy. Then, based on this table, E was determined. sd0 .

[0049] Step S103: Determine the first hidden energy based on the first theoretical maximum rated energy and the first actual rated discharge energy.

[0050] The first hidden energy is the hidden energy of the electrochemical energy storage system in its initial state.

[0051] In actual commissioning and operation, the energy actually released by the electrochemical energy storage system will be significantly less than E. s0 The difference is the hidden energy E of the electrochemical energy storage system. h The hidden energy of an electrochemical energy storage system in its initial state is different from the hidden energy after multiple cycles. The hidden energy of an electrochemical energy storage system in its initial state (i.e., the first hidden energy) can be determined by the following formula (2).

[0052] E h0 =E s0 -E sd0 (2)

[0053] In formula (2), E h0 This represents the first hidden energy.

[0054] The method for determining the hidden energy of an electrochemical energy storage system provided in this embodiment determines the first theoretical maximum rated energy based on the rated charge / discharge voltage range when the electrochemical energy storage system is in its initial operating state, and determines the first actual rated discharge energy based on the operating charge / discharge voltage range. Then, the first hidden energy is determined based on the first theoretical maximum rated energy and the first actual rated discharge energy. This invention quantitatively assesses the hidden energy of the energy storage system due to cell inconsistency and narrowing voltage range based on the operating state of the electrochemical energy storage system. This helps maintenance personnel to promptly contact the manufacturer for battery recharging and optimization of charge / discharge cutoff voltage parameters, reducing energy and economic losses caused by battery inconsistency and failure to promptly widen the charge / discharge cutoff voltage.

[0055] This invention also provides another method for determining the hidden energy of an electrochemical energy storage system, which can be used in devices for determining the hidden energy of electrochemical energy storage systems. Figure 2 This is a flowchart illustrating another method for determining the hidden energy of an electrochemical energy storage system according to an embodiment of the present invention, as shown below. Figure 2 As shown, the method includes the following steps:

[0056] Step S201: Under the condition that the electrochemical energy storage system is in its initial operating state, determine the first theoretical maximum rated energy based on the rated charge and discharge voltage range.

[0057] Please see details Figure 1 Step S101 of the illustrated embodiment will not be described again here.

[0058] Step S202: Determine the first actual rated discharge energy based on the working charge and discharge voltage range.

[0059] Please see details Figure 1 Step S102 of the illustrated embodiment will not be described again here.

[0060] Step S203: Determine the first theoretical maximum energy based on the working charge and discharge voltage range.

[0061] Specifically, the first theoretical maximum energy refers to the theoretical maximum energy that an electrochemical energy storage system in its initial state can release when discharging at rated power within its operating charge and discharge voltage range.

[0062] For example, step S203 above may include the following steps:

[0063] Step a1: Determine the first theoretical rated discharge energy based on the working charge and discharge voltage range and the initial cell charge and discharge curve.

[0064] Among them, the first theoretical rated discharge energy is the rated discharge energy that the cell can theoretically release when it discharges at rated power within the working charge and discharge voltage range in the initial state.

[0065] Battery cells at V 0low ~V 0high The rated discharge energy within the range (i.e., the first theoretical rated discharge energy) is denoted as E. ce0 E can be characterized by the integral area of ​​the initial cell charge-discharge curve within the operating charge-discharge voltage range. ce0 .

[0066] The initial cell charge-discharge curve refers to the charge-discharge curve of the cell in its initial state, with voltage as the vertical axis and capacity as the horizontal axis. By conducting charge-discharge tests on the energy storage cell within the rated rate and rated charge-discharge cutoff voltage range, a cell charge-discharge curve with voltage as the vertical axis and capacity as the horizontal axis can be obtained.

[0067] It should be understood that for the initial cell charge / discharge curve, since E = QV, the integral area of ​​the discharge curve in this curve represents the discharge energy. For actual operating power plants, due to limitations in sampling time accuracy, it is generally difficult to calculate the accurate integral area; therefore, an approximation can be made. Specifically, for example, if the voltage is observed to drop from V1 to V2 in 30 seconds, releasing a total capacity of ΔQ, then the energy released during this period is ΔQ × (V1 + V2) / 2. Summing this over the entire discharge process gives the theoretical rated discharge energy.

[0068] Step a2: Determine the first theoretical maximum energy based on the first theoretical rated discharge energy and the number of cells in the electrochemical energy storage system.

[0069] Specifically, after determining the first theoretical rated discharge energy, the first theoretical maximum energy can be determined by formula (3).

[0070] E sce0 =N×M×E ce0 (3)

[0071] In formula (3), E sce0 The first theoretical maximum energy is given by N×M, where N×M represents the number of cells in the electrochemical energy storage system.

[0072] Step S204: Determine the first hidden energy based on the first theoretical maximum rated energy and the first actual rated discharge energy.

[0073] Specifically, hidden energy E h It mainly consists of two parts: one is the hidden energy E generated by the over-sizing of the electrochemical energy storage system. he Secondly, the hidden energy E generated due to the inconsistency of battery cells. hu In this embodiment, the hidden energy generated by the over-proportioning of the electrochemical energy storage system in the initial state is denoted as the first sub-hidden energy, and the hidden energy generated by the inconsistency of the battery cells in the initial state is denoted as the second sub-hidden energy. That is, the first hidden energy is composed of the first sub-hidden energy and the second sub-hidden energy.

[0074] For example, step S204 above includes:

[0075] Step S2041: Determine the first sub-hidden energy based on the difference between the first theoretical maximum rated energy and the first theoretical maximum energy.

[0076] Step S2042: Determine the second hidden energy based on the difference between the first theoretical maximum energy and the first actual rated discharge energy.

[0077] Specifically, after determining the first theoretical maximum rated energy and the first theoretical maximum energy, the first sub-hidden energy can be obtained by the following formula (4); after determining the first theoretical maximum energy and the first actual rated discharge energy, the second sub-hidden energy can be obtained by the following formula (5).

[0078] E he0 =E s0 -E sce0 (4)

[0079] E hu0 =E sce0-E sd0 (5)

[0080] In the formula, E he0 E represents the hidden energy of the first component. hu0 This indicates that the second element contains hidden energy.

[0081] In some embodiments, after determining the first hidden energy, the method for determining the hidden energy of an electrochemical energy storage system further includes: determining the proportion of the first hidden energy, the proportion of the first sub-hidden energy, and the proportion of the second sub-hidden energy.

[0082] Specifically, the proportion of the first hidden energy can be determined by the following formula (6), the proportion of the first sub-hidden energy can be determined by the following formula (7), and the proportion of the second sub-hidden energy can be determined by the following formula (8).

[0083] α0=E h0 / E s0 (6)

[0084] β0=E he0 / E s0 (7)

[0085] γ0=E hu0 / E s0 (8)

[0086] In the formula, α0 represents the proportion of the first hidden energy, β0 represents the proportion of the first sub-hidden energy, and γ0 represents the proportion of the second sub-hidden energy.

[0087] The percentage of hidden energy can measure the energy utilization level of an electrochemical energy storage system. A higher percentage of hidden energy indicates a lower level of energy utilization, while a lower percentage indicates a higher level of energy utilization. Currently, improving the profitability of energy storage is becoming a key focus of energy storage deployment, and the level of energy utilization directly affects this profitability. Therefore, improving the energy utilization level of energy storage will be a major development trend, and the percentage of hidden energy can serve as a core indicator for evaluating energy storage utilization.

[0088] As electrochemical energy storage systems operate, batteries gradually age, and the state of energy (SOH) gradually decreases. Based on this, the present invention also provides another method for determining the hidden energy of electrochemical energy storage systems, which can be used in devices for determining the hidden energy of electrochemical energy storage systems. Figure 3 This is a flowchart illustrating another method for determining the hidden energy of an electrochemical energy storage system according to an embodiment of the present invention, as shown below. Figure 3 As shown, the method includes the following steps:

[0089] Step S301: Under the condition that the electrochemical energy storage system is in its initial operating state, determine the first theoretical maximum rated energy based on the rated charge and discharge voltage range.

[0090] Please see details Figure 1 Step S101 of the illustrated embodiment will not be described again here.

[0091] Step S302: Determine the first actual rated discharge energy based on the working charge and discharge voltage range.

[0092] Please see details Figure 1 Step S102 of the illustrated embodiment will not be described again here.

[0093] Step S303: Determine the first hidden energy based on the first theoretical maximum rated energy and the first actual rated discharge energy.

[0094] Please see details Figure 1 Step S103 of the illustrated embodiment will not be described again here.

[0095] Step S304: Under the condition that the electrochemical energy storage system has been in operation for multiple cycles, determine the second theoretical maximum rated energy based on the rated charge and discharge voltage range.

[0096] Among them, the second theoretical maximum rated energy is the theoretical maximum rated energy of the electrochemical energy storage system after multiple cycles.

[0097] Specifically, assuming the cell has undergone L cycles (L is an integer greater than 1), the second theoretical maximum rated energy can be determined by the following formula (9).

[0098] E sL =N×M×E cL (9)

[0099] In formula (9), E sL E is the second theoretical maximum rated energy. cL This indicates the maximum energy a battery cell can release after L cycles of charge-discharge cycling within its rated charge-discharge voltage range. Generally, battery cells undergo charge-discharge cycle testing, and a curve showing the relationship between discharge energy and the number of cycles will be available. The value of E can be found in a table. cL .

[0100] Step S305: Determine the second actual rated discharge energy based on the operating charge and discharge voltage range.

[0101] The second actual rated discharge energy is the rated discharge energy of the electrochemical energy storage system after multiple cycles.

[0102] Specifically, after determining the operating charge / discharge voltage range and the number of cycles, the second actual rated discharge energy E can also be determined by referring to a table. sdL .

[0103] Step S306: Determine the second hidden energy based on the second theoretical maximum rated energy and the second actual rated discharge energy.

[0104] The second hidden energy is the hidden energy of the electrochemical energy storage system after multiple cycles.

[0105] Specifically, after determining the second theoretical maximum rated energy and the second actual rated discharge energy, the second hidden energy can be determined by formula (10).

[0106] E hL =E sL -E sdL (10)

[0107] In formula (10), E hL This indicates the second hidden energy.

[0108] In this embodiment, the second hidden energy is determined by the second theoretical maximum rated energy and the second actual rated discharge energy. This establishes a relationship between the number of cycles and the hidden energy, enabling the electrochemical energy storage system to quantitatively assess the hidden energy due to cell inconsistency and narrowing voltage range during operation. This makes it easier for maintenance personnel to contact the manufacturer for timely battery charging and to optimize charge / discharge cutoff voltage parameters.

[0109] In some embodiments, the hidden energy generated by the overfitting of the electrochemical energy storage system after multiple cycles can be denoted as the third sub-hidden energy, and the hidden energy generated by the electrochemical energy storage system after multiple cycles due to cell inconsistency can be denoted as the fourth sub-hidden energy. That is, the second hidden energy is composed of the third sub-hidden energy and the fourth sub-hidden energy.

[0110] Based on this, step S306 above may include:

[0111] Step b1: Determine the third hidden energy based on the difference between the second theoretical maximum rated energy and the second theoretical maximum energy.

[0112] The second theoretical maximum energy refers to the theoretical maximum energy that the electrochemical energy storage system can release when it discharges at rated power within the operating charge and discharge voltage range after multiple cycles.

[0113] Step b2: Determine the fourth sub-hidden energy based on the difference between the second theoretical maximum energy and the second actual rated discharge energy.

[0114] Specifically, after determining the second theoretical maximum rated energy and the second theoretical maximum energy, the third sub-hidden energy can be obtained by the following formula (11); after determining the second theoretical maximum energy and the second actual rated discharge energy, the fourth sub-hidden energy can be obtained by the following formula (12).

[0115] E heL =E sL -E sceL (11)

[0116] E huL =E sceL -E sdL (12)

[0117] In the formula, E heL This indicates that the third child contains hidden energy, E. sceL E represents the maximum energy of the second theory. huL This indicates that the fourth element contains hidden energy.

[0118] In other embodiments, the third sub-hidden energy can also be determined by the following formula (13).

[0119] E heL =SOH L ×E he0 (13)

[0120] In formula (13), SOH L This indicates the health status of the battery cell after multiple cycles.

[0121] Based on formulas (11) to (13), it can be seen that the hidden energy E generated by the overfitting of the electrochemical energy storage system is heL The decrease gradually decreases with increasing cycle number, and the decrease is proportional to the SOH content. L However, the inconsistency of the battery cells increases with the number of cycles, resulting in hidden energy E. huL It will gradually increase as the number of cycles increases.

[0122] Optionally, prior to step b1 above, the method for determining the hidden energy of the electrochemical energy storage system may further include: determining the second theoretical maximum energy based on the operating charge-discharge voltage range.

[0123] Specifically, the second theoretical maximum energy can be determined by the following formula (14).

[0124] E sceL =N×M×E ceL =SOH L ×E sce0 (14)

[0125] In formula (14), E sceLE is the maximum energy according to the second theory. ceL This represents the rated discharge energy of the battery cell within the operating charge and discharge voltage range after multiple cycles (denoted as the second theoretical rated discharge energy).

[0126] Specifically, based on laboratory data, a correspondence between the number of cycles and charge-discharge curve data can be established. Knowing the number of cycles, a charge-discharge curve with voltage as the ordinate and capacity as the abscissa can be obtained. The discharge energy can then be directly predicted using the integral area within the operating charge-discharge voltage range, thus yielding E. ceL .

[0127] In some embodiments, after determining the second hidden energy, the method for determining the hidden energy of the electrochemical energy storage system further includes: determining the proportion of the second hidden energy, the proportion of the third sub-hidden energy, and the proportion of the fourth sub-hidden energy.

[0128] Specifically, the proportion of the second hidden energy can be determined by the following formula (15), the proportion of the third hidden energy can be determined by the following formula (16), and the proportion of the fourth hidden energy can be determined by the following formula (17).

[0129] α L =E hL / E sL (15)

[0130] β L =E he0 / E sL (16)

[0131] γ L =E huL / E sL (17)

[0132] In the formula, α L β represents the proportion of the second hidden energy. L γ represents the proportion of hidden energy in the third subunit. L This indicates the percentage of hidden energy in the fourth component.

[0133] This embodiment also provides a hidden energy determination device for an electrochemical energy storage system. This device is used to implement the above embodiments and preferred embodiments, and details already described will not be repeated. As used below, the term "module" can refer to a combination of software and / or hardware that performs a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, hardware implementation, or a combination of software and hardware, is also possible and contemplated.

[0134] This embodiment provides a hidden energy determination device for an electrochemical energy storage system, such as... Figure 4 As shown, the device includes:

[0135] The theoretical energy determination module 401 is used to determine the first theoretical maximum rated energy based on the first rated charge and discharge voltage range when the electrochemical energy storage system is in the initial operating state. The first theoretical maximum rated energy is the theoretical maximum rated energy of the electrochemical energy storage system in the initial state.

[0136] The actual energy determination module 402 is used to determine the first actual rated discharge energy based on the working charge and discharge voltage range, wherein the first actual rated discharge energy is the rated discharge energy of the electrochemical energy storage system in the initial state;

[0137] The hidden energy determination module 403 is used to determine the first hidden energy based on the first theoretical maximum rated energy and the first actual rated discharge energy, wherein the first hidden energy is the hidden energy of the electrochemical energy storage system in the initial state.

[0138] In some alternative embodiments, the apparatus further includes:

[0139] The maximum energy determination module is used to determine the first theoretical maximum energy based on the operating charge and discharge voltage range;

[0140] Hidden energy determination module 403 includes:

[0141] The first determining unit is used to determine the first sub-hidden energy based on the difference between the first theoretical maximum rated energy and the first theoretical maximum energy.

[0142] The second determining unit is used to determine the second hidden energy based on the difference between the first theoretical maximum energy and the first actual rated discharge energy.

[0143] In some optional implementations, the first determining unit includes:

[0144] The first determining subunit is used to determine the first theoretical rated discharge energy based on the working charge and discharge voltage range and the initial cell charge and discharge curve.

[0145] The second determining subunit is used to determine the first theoretical maximum energy based on the first theoretical rated discharge energy and the number of cells in the electrochemical energy storage system.

[0146] In some alternative embodiments, the apparatus further includes:

[0147] The first proportion determination module is used to determine the proportion of the first hidden energy, the proportion of the first sub-hidden energy, and the proportion of the second sub-hidden energy.

[0148] In some alternative embodiments, the apparatus further includes:

[0149] The first determining module is used to determine the second theoretical maximum rated energy based on the rated charge and discharge voltage range when the electrochemical energy storage system has been in operation for multiple cycles. The second theoretical maximum rated energy is the theoretical maximum rated energy of the electrochemical energy storage system after multiple cycles.

[0150] The second determining module is used to determine the second actual rated discharge energy based on the working charge and discharge voltage range, wherein the second actual rated discharge energy is the rated discharge energy of the electrochemical energy storage system after multiple cycles;

[0151] The third determining module is used to determine the second hidden energy based on the second theoretical maximum rated energy and the second actual rated discharge energy, wherein the second hidden energy is the hidden energy of the electrochemical energy storage system after multiple cycles.

[0152] In some optional embodiments, the second hidden energy includes a third sub-hidden energy and a fourth sub-hidden energy. The third sub-hidden energy is the hidden energy generated by the overfitting of the electrochemical energy storage system after multiple cycles, and the fourth sub-hidden energy is the hidden energy generated by the electrochemical energy storage system after multiple cycles due to cell inconsistency. The device further includes:

[0153] The fourth determining module is used to determine the second theoretical maximum energy based on the operating charge and discharge voltage range;

[0154] The third determination module includes:

[0155] The third determining unit is used to determine the third sub-hidden energy based on the difference between the second theoretical maximum rated energy and the second theoretical maximum energy.

[0156] The fourth determining unit is used to determine the fourth sub-hidden energy based on the difference between the second theoretical maximum energy and the second actual rated discharge energy.

[0157] In some alternative embodiments, the apparatus further includes:

[0158] The second proportion determination module is used to determine the proportion of the second hidden energy, the proportion of the third sub-hidden energy, and the proportion of the fourth sub-hidden energy.

[0159] Further functional descriptions of the above modules and units are the same as those in the corresponding embodiments described above, and will not be repeated here.

[0160] In this embodiment, the hidden energy determination device of the electrochemical energy storage system is presented in the form of a functional unit. Here, a unit refers to an application-specific integrated circuit (ASIC), a processor and memory that execute one or more software or fixed programs, and / or other devices that can provide the above functions.

[0161] This invention also provides a computer device, such as... Figure 5 As shown, the computer device includes one or more processors 510, memory 520, and interfaces for connecting the components, including high-speed interfaces and low-speed interfaces. The components are interconnected via different buses and can be mounted on a common motherboard or otherwise installed as needed. The processors can process instructions executed within the computer device, including instructions stored in or on memory to display graphical information of a GUI on external input / output devices (such as display devices coupled to the interfaces). In some alternative implementations, multiple processors and / or multiple buses can be used with multiple memories and multiple memory modules, if desired. Similarly, multiple computer devices can be connected, each providing some of the necessary operations (e.g., as a server array, a group of blade servers, or a multiprocessor system). Figure 5 Take the 510 processor as an example.

[0162] Processor 510 may be a central processing unit, a network processor, or a combination thereof. Processor 510 may further include a hardware chip. The hardware chip may be an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a combination thereof. The programmable logic device may be a complex programmable logic device (CAMP), a field-programmable gate array (FPGA), a general-purpose array logic (GDA), or any combination thereof.

[0163] The memory 520 stores instructions executable by at least one processor 510 to cause the at least one processor 510 to perform the method shown in the above embodiments.

[0164] The memory 520 may include a program storage area and a data storage area. The program storage area may store the operating system and applications required for at least one function; the data storage area may store data created based on the use of the computer device. Furthermore, the memory 520 may include high-speed random access memory and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some alternative embodiments, the memory 520 may optionally include memory remotely located relative to the processor 510, and these remote memories may be connected to the computer device via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0165] The memory 520 may include volatile memory, such as random access memory; the memory may also include non-volatile memory, such as flash memory, hard disk or solid-state drive; the memory 520 may also include a combination of the above types of memory.

[0166] The computer device also includes a communication interface 530 for communicating with other devices or communication networks.

[0167] This invention also provides a computer-readable storage medium. The methods described above according to embodiments of the invention can be implemented in hardware or firmware, or implemented as recordable on a storage medium, or implemented as computer code originally stored on a remote storage medium or a non-transitory machine-readable storage medium and subsequently stored on a local storage medium after being downloaded via a network. Thus, the methods described herein can be processed by software stored on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. The storage medium can be a magnetic disk, optical disk, read-only memory, random access memory, flash memory, hard disk, or solid-state drive, etc.; further, the storage medium may also include combinations of the above types of memory. It is understood that computers, processors, microprocessor controllers, or programmable hardware include storage components capable of storing or receiving software or computer code, which, when accessed and executed by the computer, processor, or hardware, implements the methods shown in the above embodiments.

[0168] A portion of this invention can be applied as a computer program product, such as computer program instructions, which, when executed by a computer, can invoke or provide the methods and / or technical solutions according to the invention through the operation of the computer. Those skilled in the art will understand that the forms in which computer program instructions exist in a computer-readable medium include, but are not limited to, source files, executable files, installation package files, etc. Correspondingly, the ways in which computer program instructions are executed by a computer include, but are not limited to: the computer directly executing the instructions, or the computer compiling the instructions and then executing the corresponding compiled program, or the computer reading and executing the instructions, or the computer reading and installing the instructions and then executing the corresponding installed program. Here, the computer-readable medium can be any available computer-readable storage medium or communication medium accessible to a computer.

[0169] In the description of this specification, the references to terms such as "this embodiment," "an embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0170] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0171] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the present invention.

Claims

1. A method for determining the hidden energy of an electrochemical energy storage system, characterized in that, The method includes: When the electrochemical energy storage system is in its initial operating state, the first theoretical maximum rated energy is determined based on the rated charge and discharge voltage range, wherein the first theoretical maximum rated energy is the theoretical maximum rated energy of the electrochemical energy storage system in its initial state. Based on the operating charge and discharge voltage range, the first actual rated discharge energy is determined, wherein the first actual rated discharge energy is the rated discharge energy of the electrochemical energy storage system in the initial state; Based on the first theoretical maximum rated energy and the first actual rated discharge energy, a first hidden energy is determined, wherein the first hidden energy is the hidden energy of the electrochemical energy storage system in its initial state.

2. The method according to claim 1, characterized in that, The first hidden energy includes a first sub-hidden energy and a second sub-hidden energy. The first sub-hidden energy is the hidden energy generated by the over-proportioning of the electrochemical energy storage system in its initial state. The second sub-hidden energy is the hidden energy generated by the electrochemical energy storage system in its initial state due to cell inconsistency. The method further includes: The first theoretical maximum energy is determined based on the operating charge / discharge voltage range; The determination of the first hidden energy based on the first theoretical maximum rated energy and the first actual rated discharge energy includes: The first sub-hidden energy is determined based on the difference between the first theoretical maximum rated energy and the first theoretical maximum energy. The second hidden energy is determined based on the difference between the first theoretical maximum energy and the first actual rated discharge energy.

3. The method according to claim 2, characterized in that, Determining the first theoretical maximum energy based on the operating charge / discharge voltage range includes: Based on the operating charge / discharge voltage range and the initial cell charge / discharge curve, the first theoretical rated discharge energy is determined; The first theoretical maximum energy is determined based on the first theoretical rated discharge energy and the number of cells in the electrochemical energy storage system.

4. The method according to claim 2 or 3, characterized in that, After determining the first hidden energy, the method further includes: Determine the proportion of the first hidden energy, the proportion of the first sub-hidden energy, and the proportion of the second sub-hidden energy.

5. The method according to any one of claims 1 to 3, characterized in that, The method further includes: When the electrochemical energy storage system operates under multiple cycles, a second theoretical maximum rated energy is determined based on the rated charge and discharge voltage range, wherein the second theoretical maximum rated energy is the theoretical maximum rated energy of the electrochemical energy storage system after multiple cycles. Based on the operating charge and discharge voltage range, the second actual rated discharge energy is determined, wherein the second actual rated discharge energy is the rated discharge energy of the electrochemical energy storage system after multiple cycles; Based on the second theoretical maximum rated energy and the second actual rated discharge energy, the second hidden energy is determined, wherein the second hidden energy is the hidden energy of the electrochemical energy storage system after multiple cycles.

6. The method according to claim 5, characterized in that, The second hidden energy includes a third sub-hidden energy and a fourth sub-hidden energy. The third sub-hidden energy is the hidden energy generated by the over-proportioning of the electrochemical energy storage system after multiple cycles. The fourth sub-hidden energy is the hidden energy generated by the electrochemical energy storage system after multiple cycles due to cell inconsistency. The method further includes: The second theoretical maximum energy is determined based on the operating charge / discharge voltage range. The determination of the second hidden energy based on the second theoretical maximum rated energy and the second actual rated discharge energy includes: The third sub-hidden energy is determined based on the difference between the second theoretical maximum rated energy and the second theoretical maximum energy. The fourth sub-hidden energy is determined based on the difference between the second theoretical maximum energy and the second actual rated discharge energy.

7. The method according to claim 6, characterized in that, After determining the second hidden energy, the method further includes: Determine the proportion of the second hidden energy, the proportion of the third sub-hidden energy, and the proportion of the fourth sub-hidden energy.

8. A hidden energy determination device for an electrochemical energy storage system, characterized in that, The device includes: The theoretical energy determination module is used to determine the first theoretical maximum rated energy based on the first rated charge and discharge voltage range when the electrochemical energy storage system is in the initial operating state, wherein the first theoretical maximum rated energy is the theoretical maximum rated energy of the electrochemical energy storage system in the initial state. The actual energy determination module is used to determine the first actual rated discharge energy based on the operating charge and discharge voltage range, wherein the first actual rated discharge energy is the rated discharge energy of the electrochemical energy storage system in the initial state; The hidden energy determination module is used to determine the first hidden energy based on the first theoretical maximum rated energy and the first actual rated discharge energy, wherein the first hidden energy is the hidden energy of the electrochemical energy storage system in the initial state.

9. A computer device, characterized in that, include: A memory and a processor are communicatively connected, the memory stores computer instructions, and the processor executes the computer instructions to perform the method for determining the hidden energy of the electrochemical energy storage system according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions for causing a computer to execute the method for determining the hidden energy of the electrochemical energy storage system according to any one of claims 1 to 7.

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