Energy management equipment and method for energy storage cell stack

Abstract

The invention provides energy management equipment and method for an energy storage battery stack, the equipment comprises a battery box, a battery, a battery management device and an energy storage converter PCS, the battery is arranged in the battery box, the battery is respectively connected with the battery management device, the energy storage converter PCS and a power grid through the battery box, the battery box comprises a box inner shell, a box outer shell and a box cover, the box inner shell is arranged on the inner side of the box outer shell, the bottom of the box cover is connected with the box outer shell in a buckled mode, a first cavity is formed among the box inner shell, the box outer shell and the box cover, and a phase-change material base body is arranged in the first cavity. According to the energy management equipment and method for the energy storage cell stack, the adaptability of the cell stack in the environment with the large temperature change amplitude can be effectively improved, the consistency of cells in the cell stack is achieved, the problem that the performance of different single cells is inconsistent in the charging and discharging process is solved, and the energy management efficiency of the energy storage cell stack is improved. The safety and stability of the equipment are enhanced, the cost of the equipment is reduced, and the service life of the equipment is prolonged.

Description

Technical Field

[0001] The present invention relates to the field of energy storage, and in particular to an energy storage battery stack energy management device and method. Background Art

[0002] In a battery energy storage system, multiple battery cells can form a battery stack. A battery stack refers to a whole composed of several battery cells or battery groups connected in series or in parallel. In applications such as electric vehicles and energy storage systems, battery stacks play the role of storing and releasing energy. For fuel cell stacks, the structure of the battery stack usually includes an electrode rack and its accessories, a frame assembly, etc. Its design and construction must ensure that the arrangement of electrolytes, hydrogen and oxidants is very compact. However, in existing battery stacks, as the amplitude of environmental changes at the same location becomes larger and larger, the degree of adaptability that the battery stack can make to environmental changes is relatively low.

[0003] In addition, the consistency problem within the battery stack refers to the differences in voltage, capacity, internal resistance, etc. between different battery cells, which leads to inconsistent performance of different battery cells during the charging process. Due to the consistency problem of battery cells during the battery charging process, it is easy for some battery cells in the battery stack to trigger the overvoltage or overcurrent protection mechanism prematurely during charging and stop charging, while other battery cells are in a state where they can continue to charge. However, due to the protection mechanism, the power of other battery cells cannot continue to increase, which affects the charging power of the entire battery stack, and then affects the energy utilization rate of the energy storage power station. Therefore, it is of great significance to solve the inconsistency of batteries in the battery stack under the premise of improving the adaptability of the battery stack to the environment.

[0004] In patent CN117691217A, a digital control BMS management emergency system and method are mentioned. The method specifically relates to the field of digital emergency technology, including an information division module, a data acquisition module, a system status analysis module, a system early warning analysis module, an emergency response analysis module, an information evaluation module and an information early warning module. The operation status data of the battery management system is collected by digital control technology for integration, and the operation status index, the fault early warning capability index and the emergency response index are obtained for processing and analysis to obtain the emergency response capability evaluation coefficient. By comparing the obtained emergency response capability evaluation coefficient with the preset evaluation coefficient, the emergency system is adjusted accordingly, and the digital control technology is used to intelligently monitor and locate the fault of the battery management system and to warn the management personnel, so as to improve the emergency response capability of the system in the face of emergencies and the intelligent control function of the system as a whole. However, this method is applied to the abnormal situation of the battery stack, and fails to solve the inconsistency problem between the batteries before the abnormality of the battery stack occurs, and the battery cells in the battery stack cannot effectively cope with the influence of the sudden rise or drop in temperature on the battery caused by the changeable environment. Summary of the invention

[0005] In view of this, the present invention aims to propose an energy management device for an energy storage battery stack and a management method thereof, so as to solve the problems existing in the prior art that the batteries in the battery stack cannot effectively adapt to the large temperature changes caused by the sudden rise or fall of the environment, and the inconsistency of the battery cells in the battery stack cannot be adjusted; thereby effectively improving the adaptability of the battery stack in an environment with large temperature changes, achieving the consistency of the batteries in the battery stack, avoiding the problem of inconsistency in the performance of different battery cells during the charging and discharging process, enhancing the safety and stability of the equipment, reducing the cost of the equipment, and extending the service life of the equipment.

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

[0007] The present invention relates to an energy storage battery stack energy management device and method, the energy storage battery stack energy management device comprises a battery box, a battery, a battery management device, and an energy storage converter PCS. The battery is arranged in the battery box, and the battery is connected to the battery management device, the energy storage converter PCS, and the power grid through the battery box. The battery box comprises an inner shell, an outer shell, and a cover. The inner shell is arranged on the inner side of the outer shell, and the bottom of the cover is snap-connected with the outer shell. A first cavity is formed between the inner shell, the outer shell, and the cover, and a phase change material matrix is ​​arranged in the first cavity. The battery is arranged in n numbers, where n is a positive integer. After the n batteries are arranged in series and / or in parallel, a battery stack is formed. The n batteries are arranged in a matrix arrangement inside the battery box, wherein the matrix is ​​an i×j matrix, i is the number of rows, and j is the number of columns; n=i×j. Through the arrangement of the device, the adaptability of the battery stack in an environment with a large temperature change can be effectively improved to avoid the occurrence of overheating in the battery stack.

[0008] Furthermore, the battery is connected to the battery management device, the energy storage converter PCS, and the power grid through the electronic switch assembly; n electronic switch assemblies are provided, and the n electronic switch assemblies are connected to the n batteries one by one; the battery box is provided with a backup power interface, a control interface, and a main power interface, and the backup power interface, the control interface, and the main power interface are respectively provided on the box cover; the power input end of the electronic switch assembly is connected to the energy storage converter PCS, the battery management device, and the power grid through the backup power interface, the control interface, and the main power interface. The provision of the electronic switch assembly can facilitate the improvement of the flexibility of battery switching, the efficiency of the battery management device regulation, and the service life of the equipment.

[0009] A method for energy management of an energy storage battery stack, the method being applied to the energy management device of an energy storage battery stack, the method comprising the following steps:

[0010] Step 1: Numbering: Number the batteries in the battery box separately and group them;

[0011] Step 2: Real-time monitoring and analysis: Calculate the average temperature value corresponding to each group of batteries based on the data of each battery monitored in real time in the battery management device;

[0012] Step 3: Correction: Correct the temperature average values ​​of different groups respectively and store them;

[0013] Step 4: Group abnormality judgment: Compare the average battery temperature of the selected group after correction with the preset temperature standard value of each group to determine whether the battery of the current group is abnormal. If yes, proceed to step 5; if no, repeat step 4;

[0014] Step 5: Accurately judge and process. Through the setting of the method, it is possible to effectively make a preliminary judgment first and then make an accurate judgment to accurately locate the battery 2 in the battery stack, avoid misjudgment, and help improve the accuracy and reliability of equipment management, and improve the stability and safety of battery stack operation.

[0015] Compared with the prior art, the energy storage battery stack energy management device and method described in the present invention have the following beneficial effects:

[0016] The device can effectively improve the adaptability of the battery stack in an environment with large temperature changes. Through the setting of the method, the consistency of the batteries in the battery stack can be achieved, avoiding the problem of inconsistent performance of different battery cells during the charging and discharging process, enhancing the safety and stability of the equipment, reducing the cost of the equipment, and extending the service life of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings, which constitute part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations of the present invention.

[0018] In the figure:

[0019] Figure 1 It is a schematic diagram of the overall structure of the equipment;

[0020] Figure 2 It is a schematic diagram of the management method flow chart.

[0021] Explanation of the accompanying drawings: 1. Battery box; 11. Box inner shell; 12. Box outer shell; 13. Box cover; 14. Backup power supply interface; 15. Management and control interface; 16. Main power supply interface; 2. Battery; 3. Battery management device; 4. Energy storage inverter PCS; 5. Power grid. DETAILED DESCRIPTION

[0022] The inventive concepts of the present disclosure will be described below using terms commonly used by those skilled in the art to convey the essence of their work to other persons skilled in the art. However, these inventive concepts can be embodied in many different forms and should not be considered limited to the embodiments described herein.

[0023] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0024] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0025] In order to solve the problem in the prior art that the batteries in the battery stack cannot effectively adapt to the large temperature change caused by the sudden rise or fall of the environment, and the problem that the inconsistency of the battery cells in the battery stack cannot be adjusted; this embodiment proposes an energy management device and method for an energy storage battery stack, the device includes a battery box 1, a battery 2, a battery management device 3, and an energy storage converter PCS4. The battery box 1 is provided with a battery 2, and the battery 2 is connected to the battery management device 3, the energy storage converter PCS4, and the power grid 5 through the battery box 1. The battery management device 3 monitors and analyzes the real-time operating status of the battery 2, and controls the energy storage converter PCS4 or the power grid 5 to supply power to the battery 2. The battery box 1 includes a box inner shell 11, a box outer shell 12 and a box cover 13. The box inner shell 11 is arranged on the inner side of the box outer shell 12, and the bottom of the box cover 13 is snap-connected with the box outer shell 12. A first cavity is formed between the box inner shell 11, the box outer shell 12 and the box cover 13. A phase change material matrix is ​​arranged in the first cavity to facilitate the effect of the phase change material on the battery 2 to avoid the battery 2 being affected by the rise and fall of the external environment temperature.

[0026] Through the setting of the device, the adaptability of the battery stack in an environment with large temperature changes can be effectively improved. Through the setting of the method, the consistency of the batteries in the battery stack can be achieved, avoiding the problem of inconsistent performance of different battery cells during the charging and discharging process, enhancing the safety and stability of the equipment, and reducing the cost of the equipment.

[0027] The number of batteries 2 is n, where n is a positive integer. After the n batteries 2 are arranged in series and / or in parallel, a battery stack is formed. The n batteries 2 in the battery stack are arranged in a matrix arrangement inside the battery box 1, which is used to reduce the footprint of the battery box 1 and facilitate the transportation and installation of the battery box 1. The matrix is ​​an i×j matrix, where i is the number of rows, j is the number of columns, and n=i×j. The batteries 2 are connected to the battery management device 3, the energy storage converter PCS4, and the power grid 5 through the electronic switch assembly. The electronic switch assembly can realize the function of connecting the corresponding battery 2 to the battery stack or isolating and disconnecting it. The number of electronic switch assemblies is n, and the n electronic switch assemblies are connected to the n batteries 2 one by one. The electronic switch assembly includes a main electronic switch, a main resistor, and a bypass electronic switch. The main electronic switch is connected to the positive electrode of the battery 2 through the main resistor, and the negative electrode of the battery 2 is connected to the adjacent battery 2 and / or one end of the bypass electronic switch. The other end of the bypass electronic switch is connected in parallel with the end of the main electronic switch away from the main resistor, and then connected to the adjacent battery 2. The number of main electronic switches, main resistors and bypass electronic switches are all n. In this embodiment, the connection mode between the n batteries 2 is specifically set according to the needs. The main electronic switch and bypass electronic switch are both bidirectional thyristor electronic switches.

[0028] Through the connection between each battery 2, the flexibility of the battery 2 setting in the battery stack can be effectively enhanced. It is also beneficial that when different batteries 2 have abnormalities, the abnormal battery 2 can be disconnected in time through the battery management device 3, and the normal backup battery 2 can be connected to maintain the overall power of the battery stack. Through the setting of the electronic switch, it is beneficial to improve the service life of the electronic switch, reduce the power consumption of the electronic switch, and enhance the flexibility of the electronic switch setting.

[0029] The battery box 1 is provided with a backup power interface 14, a control interface 15, and a main power interface 16. The backup power interface 14, the control interface 15, and the main power interface 16 are respectively arranged on the box cover 13 to facilitate the connection between the battery 2 and other components in the device. The power input end of the electronic switch component corresponding to the battery 2 is connected to the energy storage inverter PCS4, the battery management device 3, and the power grid 5 through the backup power interface 14, the control interface 15, and the main power interface 16. In addition, a second cavity is formed between the inner shell 11 and the box cover 13 of the battery box 1. The battery 2 is arranged in the second cavity to protect the battery 2, isolate the phase change material from the battery 2, and provide a stable installation space for the battery 2. In addition, a fan can also be arranged in the battery box 1 to cool down the temperature when the temperature in the second cavity is too high, thereby protecting the battery 2 and preventing danger.

[0030] By setting the backup power interface 14, the management interface 15, and the main power interface 16 on the box cover 13, it is beneficial to avoid affecting the airtightness of the first cavity inside the battery box 1, improve the control of the phase change material on the temperature of the battery 2, reduce the consumption of electric energy, extend the service life of the battery 2, and improve the impact of the battery 2 on the rapid changes in ambient temperature.

[0031] The battery management device 3 includes a main control chip, a processor, a memory, and a collector. The main control chip is connected to the processor, the memory, and the collector respectively. The collector is used for real-time status information of each battery 2 and uploads it to the main control chip. Under the action of the main control chip, the processor processes and analyzes it, stores the processing results in the memory, and issues instructions through the collector to control the electronic switch component to connect or disconnect the abnormal battery 2. Among them, the status information includes any one or more information of the current, voltage, and temperature of the battery 2.

[0032] The setting of the battery management device 3 is beneficial to improving the management efficiency of the equipment for each battery 2, enhancing the abnormal prevention of the battery 2, enhancing the operating reliability and stability of the battery 2, and also beneficial to ensuring the operating safety and adjustment flexibility of the battery 2, thereby extending the service life of the battery 2.

[0033] A method for energy management of an energy storage battery stack, the method being applied to the energy management device of an energy storage battery stack, the method comprising the following steps:

[0034] Step 1: Numbering: Number the batteries 2 in the battery box 1 respectively and group them;

[0035] Step 2: Real-time monitoring and analysis: Calculate the average temperature value Tij corresponding to each group of batteries 2 according to the data of each battery 2 monitored in real time in the battery management device 3;

[0036] Step 3, correction: Correct the temperature average values ​​of different groups respectively and store them. The corrected temperature average value is T'ij=kTij, where k is the temperature deviation coefficient of different groups;

[0037] Step 4: Group abnormality judgment: Compare the average temperature value of the battery 2 after correction of the selected group with the preset temperature standard value of each group to judge whether the battery 2 of the current group is abnormal. If yes, execute step 5. If no, select the average temperature value of the battery 2 of the next group and repeat step 4.

[0038] Step 5: Accurately judge and process: Analyze all batteries 2 in the abnormal group to determine whether the temperature value Tij of each battery 2 is within the preset temperature range T1-T2. If yes, judge the next battery. If not, judge the abnormal cause of the abnormal battery 2 and process it.

[0039] Through the method, it is possible to effectively achieve accurate positioning of the battery 2 in the battery stack by first making a preliminary judgment and then making an accurate judgment, thereby avoiding the occurrence of misjudgment, which is beneficial to improving the accuracy and reliability of equipment management and improving the stability and safety of the battery stack operation.

[0040] Step one includes:

[0041] Step S11: numbering each battery 2 accordingly according to the i×j matrix arrangement order of the n batteries 2 in the battery box 1;

[0042] Step S12: grouping the numbered batteries 2 in rows / columns; when grouping in rows, the number of groups is i, and when grouping in columns, the number of groups is j.

[0043] Step 4 includes:

[0044] Step S41: preset the temperature standard value of each group, according to the difference between rows and columns. When grouping by rows, preset the temperature standard value of each group as T0, and when grouping by columns, preset the temperature standard value of each group as t0;

[0045] Step S42: let i=1 or j=1;

[0046] Step S43: selecting the corrected average temperature T'ij of the battery 2 of the i / jth group;

[0047] Step S44: Compare T'ij and T0 to determine whether the battery 2 of the current group is abnormal. If yes, go to step 5; if no, go to step S45;

[0048] Step S45: Let i=i+1 or j=j+1, and determine whether i>n / j or j>n / i? If yes, all the batteries 2 in the battery box 1 are normal at the current time, and the process returns to step 2 to monitor the status of the batteries 2 in the next time period; if no, the process returns to step S43 to determine the abnormality of the next group of batteries 2. It should be noted that i or j on the left side of the equal sign represents a variable, and n / j and n / i represent the total number of rows or columns, respectively, which are both numbers and have no other suggestive meanings.

[0049] The grouping and numbering of each battery 2 in step 1 is helpful to improve the efficiency of screening abnormal batteries 2 and avoid confusion. The preliminary screening of abnormal batteries 2 in step 4 is helpful to reduce the workload of judging abnormal batteries 2.

[0050] Step five includes:

[0051] Step S51: Analyze all batteries 2 in the abnormal group, and set j=1 or i=1;

[0052] Step S52: Determine whether the temperature value tij of each battery 2 is within the preset temperature range t1-t2. If yes, execute step S53; if no, execute step S54; wherein t1 is the preset lower limit value of the normal temperature of the battery 2, and t2 is the preset upper limit value of the normal temperature of the battery;

[0053] Step S53: Let j=j+1 or i=i+1, determine whether j>n / i or i>n / j? If yes, all batteries 2 in the current abnormal group are normal, return to step 2; if no, return to step S52, and perform abnormality determination on the next battery 2 in the current group;

[0054] Step S54: determine whether the abnormal battery 2 obtained by screening is tij<t1. If yes, the temperature of the battery 2 is low, and the battery isolation instruction is issued through the battery management device 3, and the battery is replaced equivalently through the PCS. Under the action of the phase change material, the temperature of the battery 2 is adjusted until the battery 2 is connected normally. If no, execute step S55;

[0055] Step S55: Determine whether tij>third preset temperature t3. If so, the temperature of battery 2 is too high. A battery isolation instruction is issued through the battery management device 3, and the battery is replaced equivalently through the PCS. Under the joint action of the phase change material and the fan, the temperature of battery 2 is reduced until battery 2 is normally connected. If not, the temperature of battery 2 is high. A battery isolation instruction is issued through the battery management device 3, and the battery is replaced equivalently through the PCS. Under the action of the phase change material, the temperature of battery 2 is reduced until battery 2 is normally connected.

[0056] By judging the batteries 2 in the abnormal group one by one and performing corresponding processing, it is beneficial to improve the flexibility of battery stack adjustment, improve the operating stability of the battery stack, enhance the safety factor of the battery stack, and also help to extend the service life of the battery stack.

[0057] 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 principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An energy storage battery stack energy management device, characterized in that: The invention comprises a battery box (1), a battery (2), a battery management device (3), and an energy storage converter PCS (4); the battery (2) is arranged in the battery box (1); the battery (2) is connected to the battery management device (3), the energy storage converter PCS (4), and a power grid (5) through the battery box (1); the battery box (1) comprises an inner box shell (11), an outer box shell (12), and a box cover (13); the inner box shell (11) is arranged on the inner side of the outer box shell (12); the bottom of the box cover (13) is snap-connected to the outer box shell (12); a first cavity is formed between the inner box shell (11), the outer box shell (12), and the box cover (13); a phase change material matrix is ​​arranged in the first cavity.

2. The energy management device for energy storage battery stack according to claim 1, characterized in that: The number of batteries (2) is n, where n is a positive integer.

3. The energy management device for energy storage battery stack according to claim 2, characterized in that: The n batteries (2) are arranged in series and / or in parallel to form a battery stack.

4. The energy storage battery stack energy management device according to claim 3, characterized in that: The n batteries (2) are arranged in a matrix inside the battery box (1), wherein the matrix is ​​an i×j matrix, i is the number of rows, and j is the number of columns.

5. The energy storage battery stack energy management device according to claim 4, characterized in that: Said n=i×j.

6. The energy storage battery stack energy management device according to claim 2, characterized in that: The battery (2) is connected to the battery management device (3), the energy storage converter PCS (4), and the power grid (5) respectively through an electronic switch assembly.

7. The energy storage battery stack energy management device according to claim 6, characterized in that: The electronic switch components are arranged in n numbers, and the n electronic switch components are connected to the n batteries (2) in a one-to-one correspondence.

8. The energy storage battery stack energy management device according to claim 7, characterized in that: The battery box (1) is provided with a backup power supply interface (14), a control interface (15), and a main power supply interface (16); the backup power supply interface (14), the control interface (15), and the main power supply interface (16) are respectively arranged through the box cover (13).

9. The energy storage battery stack energy management device according to claim 8, characterized in that: The power input end of the electronic switch assembly is connected to the energy storage converter PCS (4), the battery management device (3) and the power grid (5) respectively through the backup power interface (14), the control interface (15) and the main power interface (16).

10. A method for managing energy storage battery stacks, characterized in that: The method is applied to an energy storage battery stack energy management device according to any one of claims 1 to 9, and the method comprises the following steps: Step 1: Numbering: Number the batteries (2) in the battery box (1) respectively and group them; Step 2: real-time monitoring and analysis: based on the data of each battery (2) monitored in real time in the battery management device (3), the average temperature value corresponding to each group of batteries (2) is calculated; Step 3: Correction: Correct the temperature average values ​​of different groups respectively and store them; Step 4: Group abnormality judgment: compare the average temperature of the battery (2) after correction of the selected group with the preset temperature standard value of each group to judge whether the battery (2) of the current group is abnormal. If yes, execute step 5; if no, repeat step 4; Step 5: Make accurate judgments and handle them.

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