A large-capacity battery energy storage system rapid power coordination control method and device

Abstract

The application provides a large-capacity battery energy storage system fast power coordination control method and device, the control method comprises the following steps: S1, obtaining the SOC value of each single battery in the battery cluster; S2, obtaining the weight coefficient K corresponding to each single battery at the current time; S3, in the same battery cluster, according to the SOC value and the weight coefficient K of each single battery, the SOC weighted average value Q of each battery cluster is calculated; S4, according to the SOC weighted average value Q of the battery cluster, the discharge power multiple or the charge power multiple of the adjustable converter corresponding to the battery cluster is adjusted; in step S2, after the energy storage system runs for a unit time t, the K corresponding to each single battery is adjusted according to the state of each single battery; the large-capacity battery energy storage system fast power coordination control method and device realize corresponding power adjustment between different battery clusters in the energy storage system, which is beneficial to improving the accuracy of power adjustment to a certain extent.

Description

Technical Field

[0001] This invention relates to a method and apparatus for rapid power coordination control of a large-capacity battery energy storage system. Background Technology

[0002] Currently, the application of lithium-ion batteries in fields such as electric vehicles and energy storage is attracting increasing attention. However, in large-scale energy storage systems, the low voltage and current of individual lithium batteries often fail to meet the requirements. Therefore, existing energy storage systems often design lithium batteries into battery clusters by connecting them in series and parallel, and then connecting the battery clusters to a power converter to perform the corresponding charging and discharging processes, thus meeting the normal power supply and energy storage operation of the energy storage system.

[0003] However, in actual use, different battery clusters are often not used under the same charging and discharging conditions, which leads to power imbalance between battery clusters. This imbalance will affect the charging and discharging capacity of the batteries, and may cause over-discharging of batteries with lower state of charge and overcharging of batteries with higher state of charge. This further aggravates the power imbalance between battery clusters, resulting in problems such as reduced battery safety and reduced cycle life in the energy storage system.

[0004] Therefore, how to coordinate the power between different battery clusters in order to solve the power imbalance problem between battery clusters has become one of the urgent problems to be solved in the field of energy storage. Summary of the Invention

[0005] In view of this, the present invention aims to propose a fast power coordination control method and device for a large-capacity battery energy storage system, so as to solve the problem of "how to coordinate the power between different battery clusters to solve the power imbalance problem between battery clusters" in the prior art.

[0006] To achieve the above objectives, the technical solution of the present invention is implemented as follows:

[0007] A fast power coordination control method for a large-capacity battery energy storage system includes: S1, acquiring the SOC value of each individual cell in the battery cluster in real time; S2, acquiring the weighting coefficient K corresponding to each individual cell at the current time; S3, within the same battery cluster, calculating the weighted average SOC value Q of each battery cluster based on the SOC value of each individual cell and the weighting coefficient K; S4, adjusting the discharge power multiple or charging power multiple of the adjustable converter corresponding to the battery cluster based on the weighted average SOC value Q of the battery cluster; in step S2, after each unit of operation time t, the energy storage system will adjust the K corresponding to each individual cell according to the state of each individual cell.

[0008] Furthermore, in step S2, the adjustment process of the weight coefficient K corresponding to any single cell includes: B1, sampling the electrolyte in the negative electrode region of the single cell; B2, detecting the hydrofluoric acid content A in the sampled electrolyte and determining whether A > HF set value; if yes, proceed to step S3; if no, keep the weight coefficient K corresponding to the single cell unchanged; B3, determining whether the sampled electrolyte contains negative electrode material particles; if yes, adjust the weight coefficient K corresponding to the single cell to the first correction value K1; if no, adjust the weight coefficient K corresponding to the single cell to the second correction value K2.

[0009] Furthermore, during the charging process, K1 > K2 > 1, and during the discharging process, K1 < K2 < 1.

[0010] Further, step B3 includes: B31, determining whether the extracted electrolyte contains negative electrode material particles; if yes, proceed to step B32; if no, adjust the weight coefficient K corresponding to the single cell to the second correction value K2; B32, detecting the mass G of negative electrode material particles per unit volume of extracted electrolyte; B33, determining whether G > warning value; if yes, proceed to step B34; if no, adjust the weight coefficient K corresponding to the single cell to the first correction value K1; B34, issuing a fault warning for the single cell and disconnecting the single cell.

[0011] Furthermore, in step S3, for a battery cluster containing n individual cells, Q = (SOC1*K1 + SOC2*K2 + ... + SOCn*Kn) / n.

[0012] Furthermore, step S4 includes: S41, calculating the average SOC of the energy storage system P based on the weighted average SOC of each battery cluster Q; S42, calculating the difference D between Q and P for any battery cluster.

[0013] S43. Determine whether D > the first preset value; if yes, increase the discharge power multiple of the adjustable converter corresponding to the battery cluster, or decrease the charging power multiple of the adjustable converter corresponding to the battery cluster; if no, proceed to step S44; S44. Determine whether D < the second preset value; if yes, decrease the discharge power multiple of the adjustable converter corresponding to the battery cluster, or increase the charging power multiple of the adjustable converter corresponding to the battery cluster; if no, maintain the discharge power multiple or charging power multiple of the adjustable converter corresponding to the battery cluster unchanged.

[0014] Furthermore, in step S4, for any battery cluster, during the charging process, the charging power factor of the adjustable converter is gradually reduced as the Q value increases, and during the discharging process, the discharging power factor of the adjustable converter is gradually reduced as the Q value decreases.

[0015] A fast power coordination device for a large-capacity battery energy storage system is provided, employing the aforementioned fast power coordination control method for a large-capacity battery energy storage system. The device includes multiple battery clusters and multiple adjustable converters, with each battery cluster and adjustable converter corresponding to a specific one. The battery clusters are connected to a load or charging grid via the adjustable converters to adjust the discharge power multiple or charging power multiple of the battery clusters.

[0016] Furthermore, the battery cluster includes multiple individual cells connected in series and / or in parallel. The casing of each individual cell includes a positive electrode region and a negative electrode region. An electrolyte is disposed inside the casing of each individual cell. An electrolyte sampling device is disposed in each individual cell. The electrolyte sampling device is connected to the negative electrode region through an electrolyte pipeline and is used to sample the electrolyte in the negative electrode region.

[0017] Furthermore, the battery cluster is equipped with a detection unit, and each individual battery cell is connected to the detection unit, which is used to detect the SOC value of the individual battery cells.

[0018] Compared with existing technologies, the fast power coordination control method and device for a large-capacity battery energy storage system described in this invention have the following advantages:

[0019] The present invention discloses a method and apparatus for rapid power coordination control of a large-capacity battery energy storage system. The method determines the weighting coefficient K of each individual battery by the state of each individual battery, and calculates the weighted average SOC value Q of the battery cluster based on the SOC value of each individual battery. The discharge power multiple or charging power multiple of the adjustable converter is adjusted by Q to achieve corresponding power regulation between different battery clusters in the energy storage system, which also helps to improve the accuracy of power regulation to a certain extent. Attached Figure Description

[0020] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0021] Figure 1 This is a schematic diagram of the structure of a fast power coordination device for a large-capacity battery energy storage system according to an embodiment of the present invention;

[0022] Figure 2 This is a schematic diagram of the structure of a single battery in a fast power coordination device for a large-capacity battery energy storage system according to an embodiment of the present invention;

[0023] Figure 3 This is a flowchart illustrating a rapid power coordination method for a large-capacity battery energy storage system according to an embodiment of the present invention.

[0024] Figure 4This is a flowchart illustrating the adjustment of the weighting coefficient K in a fast power coordination method for a large-capacity battery energy storage system according to an embodiment of the present invention. Detailed Implementation

[0025] The inventive concepts of this disclosure will be described below using terminology commonly used by those skilled in the art to communicate the essence of their work to others skilled in the art. However, these inventive concepts may be embodied in many different forms and should not be construed as limited to the embodiments described herein.

[0026] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0027] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0028] In existing energy storage systems, power imbalances often exist between different battery clusters. This imbalance affects the charge and discharge capacity of the batteries, easily leading to over-discharge of batteries with lower states of charge and overcharging of batteries with higher states of charge. This further exacerbates the power imbalance between battery clusters, resulting in reduced battery safety and cycle life in the energy storage system. Therefore, how to coordinate the power between different battery clusters has become an urgent problem to be solved.

[0029] To address the existing problem of "how to coordinate power between different battery clusters to solve the power imbalance problem between battery clusters", this embodiment proposes a fast power coordination control method and device for a large-capacity battery energy storage system. To facilitate understanding of the solution of this application, the device will be introduced first.

[0030] As attached Figure 1-4 As shown, the device includes multiple battery clusters and multiple adjustable converters. Each battery cluster is paired with a corresponding adjustable converter. The battery clusters are connected to a load or charging grid via the adjustable converters to adjust the discharge or charging power of the battery clusters. The adjustable converters are conventional AC-DC converters with adjustable charging and discharging power. Of course, if the load or charging terminal is DC, the converter can also be a DC-DC converter; however, since this is existing technology, it will not be elaborated upon.

[0031] The battery cluster comprises multiple individual cells connected in series and / or parallel. Each individual cell has a casing containing a positive electrode region and a negative electrode region. The casing of each individual cell contains a conventional lithium salt electrolyte, such as an electrolyte containing lithium hexafluorophosphate. Each individual cell is equipped with an electrolyte sampling device, which is connected to the negative electrode region via an electrolyte pipeline for sampling the electrolyte in the negative electrode region for analysis. Correspondingly, the electrolyte pipeline is also equipped with a metering pump and valve assembly (not shown) to deliver a fixed amount of electrolyte to the electrolyte sampling device when sampling is required. Of course, after sampling, the electrolyte sampling device can also replenish the negative electrode region with an appropriate amount of new electrolyte.

[0032] The battery cluster is equipped with a detection unit, and each individual battery cell is connected to the detection unit for detecting battery-related parameters. Furthermore, similar to existing technologies, the positive electrode region is equipped with a positive electrode component, which can be made of conventional materials such as lithium cobalt oxide, lithium manganese oxide, lithium iron phosphate, or ternary materials. The negative electrode region is equipped with a negative electrode component, which can be made of conventional graphite or silicon-carbon materials. Correspondingly, a separator is placed between the positive and negative electrode regions within the casing of each individual battery cell.

[0033] For ease of description, this application uniformly regards the executing entity of the control method as the device; at the same time, since the device is also part of the entire energy storage system, the executing entity of the control method can also be regarded as the energy storage system.

[0034] The control method includes:

[0035] S1. The SOC value of each individual cell in the battery cluster is obtained in real time through the detection unit;

[0036] The detection unit includes at least a detector for the state of charge (SOC) of a single cell. Given that the technology for detecting and acquiring SOC is relatively conventional, this application will not elaborate further.

[0037] S2. Obtain the weight coefficient K corresponding to each individual battery at the current time;

[0038] Here, K represents the data stored in the device's memory at the current time point, and each individual battery cell has a corresponding K. Furthermore, after each unit of operating time t, the device adjusts K according to the state of each individual battery cell and simultaneously updates the corresponding K value stored in the memory. For any given individual battery cell, the device can directly retrieve the corresponding K from the memory.

[0039] Correspondingly, since the control logic between battery charging and discharging is reversed, K in this application also needs to be divided into charging and discharging processes, with charging and discharging corresponding to different data. For a new battery, the initial weighting coefficient set in the memory is 1 (charging process) and 1 (discharging process).

[0040] It should be noted that the rated values ​​and preset values ​​involved in this application, such as the unit duration t, are all data preset during the design and development of the energy storage system based on the scale of the energy storage system, operation and maintenance specifications, and other conditions. Given that different energy storage systems often have significant differences in scale, battery performance, operating environment, and operation and maintenance requirements, the relevant preset data will not be entirely the same. Therefore, this application does not specifically limit the relevant preset data, but only provides a few reference data as examples, such as the unit duration t being 30 days, 60 days, etc.

[0041] S3. Within the same battery cluster, calculate the weighted average SOC value Q of each battery cluster based on the SOC value of each individual cell and the weighting coefficient K.

[0042] The weighted average value is defined mathematically as follows: for a battery cluster containing n individual cells, Q = (SOC1*K1 + SOC2*K2 + ... + SOC...). n *K n ) / n, where the subscript corresponds to a specific battery in a particular order within the battery cluster.

[0043] S4. Adjust the discharge power factor or charging power factor of the adjustable converter corresponding to the battery cluster based on the weighted average value Q of the SOC of the battery cluster.

[0044] For any given battery cluster, during the charging process, the charging power factor is gradually reduced as the Q value increases, and during the discharging process, the discharging power factor is gradually reduced as the Q value decreases, thereby enabling corresponding power regulation and control between different battery clusters in the energy storage system.

[0045] This application determines the weighting coefficient K of each individual cell by the state of each individual cell, and calculates the weighted average SOC value Q of the battery cluster based on the SOC value of each individual cell. The discharge power multiple or charging power multiple of the adjustable converter is adjusted by Q to realize the corresponding power adjustment between different battery clusters in the energy storage system, which also helps to improve the accuracy of power adjustment to a certain extent.

[0046] In step S2, the adjustment process of the weight coefficient K corresponding to any single cell includes:

[0047] B1. Periodically sample the electrolyte in the negative electrode area of ​​a single cell using an electrolyte sampling device;

[0048] The term "periodic" is the same as "unit duration t" mentioned earlier, and will not be repeated here.

[0049] B2. Detect the hydrofluoric acid content A in the extracted electrolyte and determine whether A > HF set value; if yes, proceed to step B3; if no, keep the weight coefficient K corresponding to the single cell unchanged.

[0050] For the detection of hydrofluoric acid content, existing technologies can be used, such as acid-base titration with NaOH ethanol solution. This process can be performed using commercially available automatic titration instruments, or by manual titration using bromocresol green as an indicator.

[0051] The HF setting value is also affected by factors such as the product quality and battery performance of different battery suppliers. This application does not impose specific limitations on it, but only provides some reference data as examples, such as a HF setting value of 0.008% by mass percentage. Taking an electrolyte containing lithium hexafluorophosphate as an example, trace amounts of hydrofluoric acid inevitably enter the battery during the production process. When A ≤ HF setting value, it will not have a significant impact on the battery capacity for the time being, and the current K value of the single cell can be maintained. If A > HF setting value, it indicates that there may be a certain amount of HF inside the battery, which increases the risk of excessive consumption of lithium ions and will affect the capacity and cycle efficiency of the lithium battery. It is necessary to adjust the K value of the single cell in a timely manner.

[0052] B3. Determine whether the extracted electrolyte contains negative electrode material particles; if so, adjust the weight coefficient K corresponding to the single cell to the first correction value K1; if not, adjust the weight coefficient K corresponding to the single cell to the second correction value K2.

[0053] The detection of negative electrode material particles can be carried out using existing technologies, such as electron microscopy, or by taking a portion of the electrolyte, diluting it according to a certain volume ratio, filtering the diluted mixture, and then sieving the negative electrode material particles from the filter cake.

[0054] K1 and K2 are both preset values. In this application, K1 corresponds to different values ​​depending on the charging and discharging process, and so does K2. For a single cell or a battery cluster, K1 > K2 > 1 during charging and K1 < K2 < 1 during discharging. Thus, on the one hand, this application can adjust the power of the battery cluster more accurately according to the different charging and discharging processes of the battery cluster, and on the other hand, it can also help to avoid overcharging and over-discharging of the degraded batteries in the battery cluster to a certain extent.

[0055] Furthermore, due to the influence of product quality and battery performance from different battery suppliers, this application does not impose specific limitations on it, but only provides some reference data as examples, such as: during the discharge process, K1 is 0.60-0.80, K2 is 0.85-0.95, and during the charging process, K1 is 1.25-1.40, K2 is 1.05-1.20. Of course, K1 and K2 can also be corrected by the battery supplier according to the charging and discharging data.

[0056] For conventional graphite and silicon-carbon anode materials, the anode undergoes volume changes during battery charging and discharging, and expands to a certain extent during lithium intercalation. Due to differences in product quality, battery performance, and operating conditions among different anode suppliers, the anode material may break down and pulverize after its volume expands to a certain degree. This leads to a continuous increase in internal resistance and polarization, easily causing battery capacity decay. Furthermore, some anode material particles stripped from the anode may enter the electrolyte. This application, based on HF detection and analysis, further analyzes the anode material particles to obtain the current internal state of the battery, and adjusts the weighting coefficient K according to the different analysis results.

[0057] Therefore, this application collects electrolyte samples from the negative electrode region and analyzes the hydrofluoric acid content and negative electrode material particles to adjust the weighting coefficient K. On the one hand, it can easily and conveniently detect and analyze the internal state of the battery, which is conducive to improving the efficiency of detection and analysis. On the other hand, it can obtain the current internal state of the battery more accurately, which is conducive to timely and accurate adjustment of the weighting coefficient K to improve the accuracy of power regulation and control.

[0058] In addition, step B3 includes:

[0059] B31. Determine whether the extracted electrolyte contains negative electrode material particles; if yes, proceed to step B32; if no, adjust the weighting coefficient K corresponding to the single cell to the second correction value K2.

[0060] B32. Detect the mass G of negative electrode material particles in a unit volume of extracted electrolyte;

[0061] Among them, the detection of G is preferably carried out through the dilution and sieving process in the existing technology. A certain volume V of electrolyte is taken, diluted according to a certain volume ratio, the diluted mixture is filtered, the negative electrode material particles are sieved from the filter cake, and the mass g of the sieved negative electrode material particles is detected, G = g / V.

[0062] B33. Determine if G > warning value; if yes, proceed to step B34; if no, adjust the weight coefficient K corresponding to the individual battery cell to the first correction value K1.

[0063] The warning value is a set value, which is affected by the product quality of different negative electrode suppliers, battery performance, and battery operating conditions. This application does not make specific restrictions on it, but only provides some reference data as examples, such as a warning value of 10-50 mg / L.

[0064] B34. Issue a fault warning for the individual battery cell and disconnect the individual battery cell.

[0065] In the process of detecting and analyzing negative electrode material particles, this application sets a warning value. If G is not greater than the warning value, the K value of the corresponding battery in the memory is adjusted, and the battery can operate normally according to the control method of this application. If G > the warning value, it indicates that the battery may have excessive negative electrode stripping, resulting in excessively high internal resistance, severe battery capacity decay, or even failure to meet the requirements of the energy storage system. Therefore, the battery is warned and disconnected. This effectively identifies the specific faulty battery in the battery cluster, facilitating subsequent maintenance and replacement by operation and maintenance personnel. It also avoids potential safety hazards during the charging and discharging of faulty batteries.

[0066] Step S4 includes:

[0067] S41. Calculate the average SOC of the energy storage system, P, based on the weighted average SOC of each battery cluster, Q.

[0068] S42. For any battery cluster, calculate the difference D between Q and P;

[0069] Where P is the average in the conventional mathematical sense. Taking an energy storage battery system containing m battery clusters as an example, P = (Q1 + Q2 + ... + Qm) / m; D = QP.

[0070] S43. Determine whether D > the first preset value; if yes, increase the discharge power multiple of the adjustable converter corresponding to the battery cluster, or decrease the charging power multiple of the adjustable converter corresponding to the battery cluster; if no, proceed to step S44.

[0071] S44. Determine whether D < the second preset value; if yes, reduce the discharge power multiple of the adjustable converter corresponding to the battery cluster, or increase the charging power multiple of the adjustable converter corresponding to the battery cluster; if no, keep the discharge power multiple or charging power multiple of the adjustable converter corresponding to the battery cluster unchanged.

[0072] The first preset value and the second preset value are preset values ​​of the energy storage system. Due to the different operating environments and maintenance conditions of different energy storage systems, this application does not make specific limitations on them, but only provides some reference data as examples, such as: the first preset value is 0.10 to 0.25, and the second preset value is -0.20 to -0.10.

[0073] While steps S41-S44 are running, the following can still be maintained: for any given battery cluster, during charging, the charging power factor of the adjustable converter gradually decreases as the Q value increases; during discharging, the discharging power factor of the adjustable converter gradually decreases as the Q value decreases. However, it is recommended to prioritize steps S41-S44 to fully ensure power balance among the various battery clusters in the energy storage system.

[0074] In this invention, any energy storage system may include the device described in this embodiment, or it may employ the control method described in this embodiment. Accordingly, while employing the control method, the device (which can also be considered an energy storage system) further includes: a central processing unit, used at least for calculating, analyzing, processing, controlling components, and retrieving data related to the processes in the control method; a memory, used at least for storing relevant data in the control method; and an early warning unit, used for performing corresponding early warning and alarm actions upon detecting an anomaly. In addition, other conventional components of conventional energy storage systems may also be included, but since these are prior art, they will not be described in detail here.

[0075] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for rapid power coordination control of a large-capacity battery energy storage system, characterized in that, The control method includes: S1. Real-time acquisition of the SOC value of each individual cell in the battery cluster; S2. Obtain the weight coefficient K corresponding to each individual battery at the current time; S3. Within the same battery cluster, calculate the weighted average SOC value Q of each battery cluster based on the SOC value of each individual cell and the weighting coefficient K. S4. Adjust the discharge power factor or charging power factor of the adjustable converter corresponding to the battery cluster based on the weighted average value Q of the SOC of the battery cluster. In step S2, after each unit of time t of operation, the energy storage system will adjust the K corresponding to each individual battery according to the state of each individual battery. In step S2, the adjustment process of the weight coefficient K corresponding to any single cell includes: B1. Sample the electrolyte in the negative electrode region of a single cell; B2. Detect the hydrofluoric acid content A in the extracted electrolyte and determine whether A > HF set value; if yes, proceed to step S3; if no, keep the weight coefficient K corresponding to the single cell unchanged. B3. Determine whether the extracted electrolyte contains negative electrode material particles; if so, adjust the weight coefficient K corresponding to the single cell to the first correction value K1; if not, adjust the weight coefficient K corresponding to the single cell to the second correction value K2. During charging, K1 > K2 > 1; during discharging, K1 < K2 < 1.

2. The fast power coordination control method for a large-capacity battery energy storage system according to claim 1, characterized in that, Step B3 includes: B31. Determine whether the extracted electrolyte contains negative electrode material particles; if yes, proceed to step B32; if no, adjust the weighting coefficient K corresponding to the single cell to the second correction value K2. B32. Detect the mass G of negative electrode material particles in a unit volume of extracted electrolyte; B33. Determine if G > warning value; if yes, proceed to step B34; if no, adjust the weight coefficient K corresponding to the individual battery cell to the first correction value K1. B34. Issue a fault warning for the individual battery cell and disconnect the individual battery cell.

3. The fast power coordination control method for a large-capacity battery energy storage system according to claim 1, characterized in that, In step S3, for a battery cluster containing n individual cells, Q = (SOC1) K1+SOC2 K2+……+SOC n K n ) / n.

4. The fast power coordination control method for a large-capacity battery energy storage system according to claim 1, characterized in that, Step S4 includes: S41. Calculate the average SOC of the energy storage system, P, based on the weighted average SOC of each battery cluster, Q. S42. For any battery cluster, calculate the difference D between Q and P; S43. Determine whether D > the first preset value; if yes, increase the discharge power multiple of the adjustable converter corresponding to the battery cluster, or decrease the charging power multiple of the adjustable converter corresponding to the battery cluster; if no, proceed to step S44. S44. Determine whether D < the second preset value; if yes, reduce the discharge power multiple of the adjustable converter corresponding to the battery cluster, or increase the charging power multiple of the adjustable converter corresponding to the battery cluster; if no, keep the discharge power multiple or charging power multiple of the adjustable converter corresponding to the battery cluster unchanged.

5. The fast power coordination control method for a large-capacity battery energy storage system according to claim 1, characterized in that, In step S4, for any battery cluster, during the charging process, the charging power factor of the adjustable converter is gradually reduced as the Q value increases, and during the discharging process, the discharging power factor of the adjustable converter is gradually reduced as the Q value decreases.

6. A rapid power coordination device for a large-capacity battery energy storage system, characterized in that, The device employs the fast power coordination control method for a large-capacity battery energy storage system as described in any one of claims 1-5; the device includes multiple battery clusters and multiple adjustable converters, with each battery cluster and adjustable converter corresponding to one another, and the battery clusters connected to a load or charging grid via the adjustable converters to adjust the discharge power multiple or charging power multiple of the battery clusters.

7. A fast power coordination device for a large-capacity battery energy storage system according to claim 6, characterized in that, The battery cluster includes multiple individual cells connected in series and / or in parallel. The casing of each individual cell includes a positive electrode region and a negative electrode region. An electrolyte is disposed inside the casing of each individual cell. Each individual cell is equipped with an electrolyte sampling device, which is connected to the negative electrode region through an electrolyte pipeline for sampling the electrolyte in the negative electrode region.

8. A fast power coordination device for a large-capacity battery energy storage system according to claim 7, characterized in that, The battery cluster is equipped with a detection unit, and each individual battery cell is connected to the detection unit, which is used to detect the SOC value of the individual battery cells.

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