Power storage facility and method for controlling power storage facility

Abstract

A power storage facility 10 according to the present disclosure comprises: a housing; banks A, B, C, and D configured by electrically connecting a plurality of power storage elements in series; and a protection unit 100 that opens and closes power lines of the banks A, B, C, and D. The plurality of banks A, B, C, and D are housed in the housing. The plurality of banks A, B, C, and D have a first bank A and a second bank B arranged side by side in the vertical direction. The first bank A has first bank rows A1 and A2 in which the plurality of power storage elements are arranged side by side in a direction intersecting the vertical direction. The second bank B has second bank rows B1 and B2 in which the plurality of power storage elements are arranged side by side in the direction intersecting the vertical direction. The first bank A and the second bank B are electrically connected in parallel.

Description

Electricity storage facility and control method for electricity storage facility

[0001] The present disclosure relates to an electricity storage facility.

[0002] For example, the facility described in Japanese Patent Laid-Open Publication No. 2023-72872 (Patent Document 1 below) is known as an energy storage facility in which multiple energy storage devices are arranged vertically. The energy storage facility includes a box-shaped housing and multiple energy storage devices housed within the housing. The vertically arranged energy storage devices are connected to each other by bus bars. This configuration in which multiple energy storage elements are connected in series is called a bank.

[0003] JP 2023-72872 A

[0004] The energy storage elements generate heat during charging and discharging, causing the upper part of the housing to reach a high temperature, while the lower part of the housing is kept at a lower temperature. As a result, the upper energy storage elements in a bank are more susceptible to deterioration due to heat, while the lower energy storage elements are less susceptible to deterioration. If there is a difference in the deterioration of the energy storage elements within a bank, there is a concern that the deterioration of some energy storage elements will affect the lifespan of the entire energy storage device.

[0005] The present disclosure was completed in light of the above circumstances, and aims to suppress deterioration of an energy storage element.

[0006] The energy storage equipment of the present disclosure includes a housing, a bank configured by a plurality of energy storage elements electrically connected in series, and a protection unit that opens and closes the power lines of the bank, wherein the plurality of banks are housed in the housing, the plurality of banks having a first bank and a second bank arranged side by side in a vertical direction, the first bank having a first bank row in which the plurality of energy storage elements are arranged side by side in a direction intersecting the vertical direction, the second bank having a second bank row in which the plurality of energy storage elements are arranged side by side in a direction intersecting the vertical direction, and the first bank and the second bank being electrically connected in parallel.

[0007] According to the present disclosure, deterioration of the energy storage element can be suppressed.

[0008] Fig. 1 is a perspective view of an electric storage facility; Fig. 2 is a block diagram showing an electrical configuration of the electric storage facility; Fig. 3 is a diagram showing in a simplified manner a plurality of banks arranged side by side in the vertical direction in Example 1; Fig. 4 is a diagram showing in a simplified manner a plurality of banks arranged side by side in the horizontal direction in a conventional example; and Fig. 5 is a diagram showing in a simplified manner a plurality of banks arranged side by side in the vertical direction in Example 2.

[0009] (Summary of this embodiment) (1) The energy storage equipment of the present disclosure includes a housing, a bank configured by a plurality of energy storage elements electrically connected in series, and a protection unit that opens and closes the power lines of the bank, the plurality of banks being housed in the housing, the plurality of banks having a first bank and a second bank arranged side by side in a vertical direction, the first bank having a first bank row in which the plurality of energy storage elements are arranged side by side in a direction intersecting the vertical direction, the second bank having a second bank row in which the plurality of energy storage elements are arranged side by side in a direction intersecting the vertical direction, and the first bank and the second bank being electrically connected in parallel.

[0010] Because heat generated inside the housing flows upward, banks located higher in the system are more likely to reach high temperatures. Depending on the usage conditions of the energy storage equipment, such as when a large amount of power is not required, it may not be necessary to use both the first and second banks, and it may be sufficient to use only one of the banks. In this case, by opening the bank that has reached a high temperature using the protection unit (disconnecting it from the power line) and continuing to use the remaining banks, deterioration of the banks can be suppressed, and deterioration (reduced lifespan) of the energy storage equipment can be suppressed.

[0011] If a difference in deterioration occurs between the energy storage elements within a bank, the deteriorated energy storage elements become a bottleneck, resulting in a significant decrease in the performance of the energy storage equipment, such as a decrease in the maximum charge / discharge current output and a decrease in the full charge capacity (FCC). The energy storage equipment disclosed herein makes it difficult for a difference in deterioration to occur between the energy storage elements within a bank. Because the deterioration of multiple energy storage elements within each bank progresses almost evenly, by replacing only the bank that requires replacement, the performance of the energy storage equipment can be maintained while reducing the cost required for replacement.

[0012] (2) In the energy storage equipment described in (1), it is preferable that the first bank is arranged above the second bank, the first bank is configured with a pair of first bank rows arranged side by side in the vertical direction, and the upper first bank row and the lower first bank row are electrically connected in series.

[0013] Among the first banks, the first bank row arranged at the top is more susceptible to deterioration due to heat, so by replacing only the first bank row arranged at the top, the cost required for replacement can be reduced.

[0014] (3) In the storage battery equipment described in (1), it is preferable that the first bank is disposed above the second bank, and the first bank is configured to include only one row of the first bank.

[0015] Since the first bank is composed of a plurality of storage elements arranged at the same height in the vertical direction, the variation in deterioration of the storage elements in the first bank can be further reduced.

[0016] <Embodiments> Hereinafter, embodiments will be described in detail with reference to the drawings. In the following description, the up-down direction refers to the up-down direction shown by the arrows in Fig. 1, e.g., the vertical direction. Furthermore, the direction intersecting the up-down direction refers to the left-right direction shown by the arrows in Fig. 1, e.g., the horizontal direction. Furthermore, the direction perpendicular to both the up-down direction and the left-right direction is referred to as the front-rear direction.

[0017] The power storage device 10 is a device capable of charging with electricity from an external source and discharging electricity to an external source. In this embodiment, the power storage device 10 has a rectangular parallelepiped shape. The power storage device 10 is a stationary battery panel used for power storage or power supply purposes. Specifically, the power storage device 10 is used as a stationary battery for home or business use. The power storage device 10 can also be used as a battery for driving or starting the engine of a large mobile object such as a ship or an electric railway vehicle. Examples of the electric railway vehicle include electric trains, monorails, linear motor cars, and hybrid electric trains equipped with both a diesel engine and an electric motor. The power storage device 10 may be used in automobiles, motorcycles, personal watercraft, snowmobiles, agricultural machinery, construction machinery, or the like, as long as it is compact. Examples of the automobiles include electric vehicles (EVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and fossil fuel (gasoline, diesel, liquefied natural gas, etc.) vehicles.

[0018] As shown in Fig. 1, the energy storage facility 10 includes a metal battery panel 11 and a plurality of energy storage modules L. The plurality of energy storage modules L are configured into a plurality of banks A, B, C, and D using wiring (not shown). The battery panel 11 shown in Fig. 1 houses a plurality of banks A, B, C, and D, each consisting of two long rows of energy storage modules L in the left-right direction. The battery panel 11 corresponds to the housing of the present disclosure, and the energy storage modules correspond to the energy storage elements of the present disclosure.

[0019] The battery panel 11 has a pair of opening / closing doors 12 on the front side. A plurality of shelves 13 are provided at intervals in the vertical direction inside the battery panel 11. Although not shown, an exhaust port is provided on the rear side of the battery panel 11. The housing of the present disclosure is not limited to a battery panel 11 having such a pair of opening / closing doors 12.

[0020] The energy storage module L may be configured by connecting a plurality of energy storage cells (e.g., lithium-ion battery cells) in series and / or parallel. The energy storage cells may be rectangular cells (prismatic cells), cylindrical cells, or laminated cells (pouch cells). The energy storage module L has an elongated shape (e.g., a rectangular parallelepiped shape) extending from the front surface to the rear surface of the battery panel 11. The energy storage module L is inserted between a pair of vertically adjacent shelves 13 from the front of the battery panel 11.

[0021] A protection unit 100 is disposed on the top shelf 13 inside the battery panel 11. In the example of FIG. 1 , four protection units 100 are arranged side by side in the left-right direction inside the battery panel 11. Each protection unit 100 has an elongated shape extending from the front to the rear of the battery panel 11. Each protection unit 100 is provided corresponding to each bank A, B, C, and D.

[0022] Example 1 Next, Example 1 of this embodiment will be described with reference to FIGS. 3 and 4. The multiple banks A, B, C, and D are, from top to bottom, a first bank A, a second bank B, a third bank C, and a fourth bank D. Since the banks A, B, C, and D have the same configuration, the first bank A will be described as a representative. As shown in FIG. 3, the first bank A is disposed above the second bank B, which is disposed above the third bank C, which is disposed above the fourth bank D. Note that in FIGS. 3 and 4, the energy storage modules are denoted as A01, A02, etc. instead of L.

[0023] As shown in FIG. 3 , the first bank A includes a pair of upper and lower first bank columns A1 and A2, each including a plurality of power storage modules A01, ..., A16 arranged side by side. The upper first bank column A1 includes eight power storage modules A01, ..., A08 arranged side by side in the left-right direction, while the lower first bank column A2 includes eight power storage modules A09, ..., A16 arranged side by side in the left-right direction. The upper first bank column A1 and the lower first bank column A2 are electrically connected directly to each other. As shown in FIG. 2 , the power storage modules A01, ..., A16 are electrically connected in series. The banks A, B, C, and D are electrically connected in parallel.

[0024] As shown in Figure 3, the second bank B is configured to include a second bank column B1 arranged above and a second bank column B2 arranged below, the third bank C is configured to include a third bank column C1 arranged above and a third bank column C2 arranged below, and the fourth bank D is configured to include a fourth bank column D1 arranged above and a fourth bank column D2 arranged below.

[0025] In the present embodiment, each bank is configured by electrically connecting two rows of 16 energy storage modules in series, but the number of energy storage modules constituting each bank can be selected arbitrarily. For example, a bank may be configured by one and a half rows of energy storage modules or one row of energy storage modules. Furthermore, although not shown, a connector or terminal for electrical connection with a laterally adjacent energy storage module or protection unit 100 may be provided on the front surface of each energy storage module. With the above configuration, the energy storage module to be replaced can be removed from the battery panel 11 by disconnecting the connection between the energy storage module to the adjacent energy storage module or protection unit 100 via the connector or terminal. This allows an operator to easily replace a faulty energy storage module from the front surface of the energy storage equipment.

[0026] FIG. 2 shows the electrical configuration of the energy storage facility 10. In FIG. 2, the protection unit 100 is not shown, and the energy storage modules are denoted as L. A plurality of energy storage modules L are connected in series to form banks A, B, C, and D. As described above, in this embodiment, four banks A, B, C, and D are housed in one battery panel 11. The energy storage facility 10 has a hierarchical structure of banks A, B, C, and D and domains in which a plurality of banks A, B, C, and D are connected in parallel. The power lines of each of the banks A, B, C, and D are connected to main circuit lines (e.g., bus bars capable of carrying large currents) not shown.

[0027] In the example of FIG. 2 , the management units provided in banks A, B, C, and D are denoted by 30, and the management unit provided in a domain is denoted by 20. The management units 30 communicate with control boards (cell management units) L1 with communication functions built into the power storage modules L in banks A, B, C, and D via serial communication via a communication line 121. The management units 30 also acquire temperature data measured in the power storage modules L and current data measured for each of banks A, B, C, and D. The management unit 30 may perform management processes such as detecting abnormalities in the communication state.

[0028] The management unit 20 can communicate with the management units 30 of banks A, B, C, and D via a communication bus 120. The communication bus 120 is, for example, a CAN bus. Alternatively, the communication bus 120 may be a LAN cable or an ECHONET / ECHONET Lite (registered trademark) compatible communication medium.

[0029] The management unit 20 may aggregate the status data acquired by the management units 30 of banks A, B, C, and D. A communication device 4 is connected to the management unit 20. The communication device 4 transmits the status data acquired from each management unit 30 via the management unit 20.

[0030] The communication device 4 may be a terminal device (measurement monitor) that communicates with the management units 20, 30 to receive information about the power storage module L, or may be an ECHONET / ECHONET Lite (registered trademark) compatible controller. The communication device 4 may be an independent device, such as a router-type communication device. The communication device 4 may also be a network card-type device (network interface card).

[0031] The communication device 4 can receive instructions from an external device (for example, an operator's terminal) and cause each management unit 30 to open or close the electromagnetic contactor 110 shown in FIG.

[0032] Next, the operation and effect of the energy storage facility 10 according to Example 1 of this embodiment will be described with reference to Fig. 3 and Fig. 4 . As shown in Fig. 3 , each of the first bank A to the fourth bank D is provided with an electromagnetic contactor 110. Therefore, all of the electromagnetic contactors 110 are normally closed (on state), but are switched to an open state (off state) when an overcurrent or short circuit occurs. The protection unit 100 can freely open and close each of the electromagnetic contactors 110.

[0033] For example, if all banks A, B, C, and D are not needed, opening the electromagnetic contactor 110 of the first bank A allows only the other banks B, C, and D to be used. The first bank A is located at the top of the battery panel 11, where heat tends to build up, and is therefore prone to high temperatures. The hatching in FIG. 3 indicates that the darker the hatching, the higher the temperature. If the first bank A continues to be used in the upper part of the battery panel 11 that has reached a high temperature, the energy storage modules A01, ..., A08 of the first bank A are likely to deteriorate due to heat. Therefore, by disconnecting only the first bank A, which has the highest temperature among all banks A, B, C, and D, from the power line, deterioration of the first bank A can be suppressed, and as a result, the shortening of the lifespan of the energy storage equipment 10 can be suppressed.

[0034] For comparison, the bank arrangement in a conventional energy storage facility is shown in FIG. 4. In the example of FIG. 4, a first bank 1A, a second bank 1B, a third bank 1C, and a fourth bank 1D are arranged from left to right in the figure. The first bank 1A is configured with a pair of left and right first bank columns 1A1 and 1A2 from left to right in the figure. In the left first bank column 1A1, energy storage modules A01, ..., A08 are arranged in order from top to bottom, and in the right first bank column 1A2, energy storage modules A09, ..., A16 are arranged in order from bottom to top. The same applies to the second bank 1B, the third bank 1C, and the fourth bank 1D.

[0035] If heat builds up inside the battery panel 11 and the upper part becomes hot, the power storage modules A01 and A16 of the first bank 1A, the power storage modules B01 and B16 of the second bank 1B, the power storage modules C01 and C16 of the third bank 1C, and the power storage modules D01 and D16 of the fourth bank 1D are likely to deteriorate due to the heat. In the example of FIG. 4 , even if only a portion of each bank 1A, 1B, 1C, or 1D deteriorates, all of the banks 1A, 1B, 1C, and 1D must be replaced. In contrast, in this embodiment, only the first bank A needs to be replaced, which significantly reduces the cost required for replacement.

[0036] In a conventional energy storage facility, even if some of the energy storage modules in all of the banks 1A, 1B, 1C, and 1D deteriorate, the performance of each of the banks 1A, 1B, 1C, and 1D deteriorates due to the deteriorated energy storage modules, resulting in a significant deterioration in the performance of the entire energy storage facility. In contrast, in the energy storage facility 10 of the present disclosure, only the topmost first bank A deteriorates, and the other banks B, C, and D are less likely to deteriorate. This reduces the impact on the entire energy storage facility 10, such as a decrease in maximum charge / discharge current output and a significant decrease in actual capacity (FCC). Furthermore, according to the first embodiment, a bank can be disconnected from the power line by opening the electromagnetic contactor 110, and power can be supplied from the other bank to the load or the grid by closing the electromagnetic contactor 110 of the other bank. This allows a faulty energy storage module belonging to the bank disconnected from the power line to be replaced while the energy storage facility 10 is operating.

[0037] Example 2 Next, Example 2 of this embodiment will be described with reference to FIG. 5 . Example 2 illustrates an energy storage facility 10 in which the first bank A through the eighth bank H are electrically connected in parallel. The first bank A is configured with only a single first bank column A1. The first bank column A1 is configured with 16 energy storage modules A01 through A16 arranged side by side in the left-right direction. The energy storage modules A01 through A16 are electrically connected in series. Similarly, the second bank B is configured with only a single second bank column B1, and the third bank C through the eighth bank H are each configured with only a single third bank column C1 through eighth bank column H1. Each of the first bank A through the eighth bank H is provided with an electromagnetic contactor 110. Each management unit 30 can open and close the electromagnetic contactor 110.

[0038] According to Example 2, the first bank A is composed of a row of storage modules A01, ..., A16 aligned in the left-right direction, and there is no difference in height between the storage modules A01, ..., A16 in the vertical direction, which further reduces the deterioration variation among the storage modules A01, ..., A16 within the first bank A.

[0039] <Other Embodiments> The present disclosure is not limited to the embodiments described above and illustrated in the drawings, but is intended to include all modifications within the meaning and scope of the claims as defined by the claims. The technical scope of the present disclosure also includes, for example, the following embodiments.

[0040] Although the above embodiments exemplify a power storage facility including the first to fourth banks and a power storage facility including the first to eighth banks, any power storage facility may be used as long as it includes at least the first bank and a bank located below it (for example, one of the second, third, and fourth banks). In other words, the bank that is in the highest temperature state among the multiple banks corresponds to the first bank of the present disclosure, and the bank located below it corresponds to the second bank of the present disclosure.

[0041] In the above embodiments, examples have been given of eight storage modules arranged side by side in the left-right direction in one bank row, and sixteen storage modules arranged side by side in the left-right direction in one bank row, but the number of storage modules is not important.

[0042] In the above embodiments, examples have been given in which one bank is configured with a pair of upper and lower bank columns, and one bank is configured with only one bank column, but the number of bank columns in one bank may be three or more.

[0043] In the above embodiment, the protection units 100 are arranged side by side in the left-right direction on the top shelf plate inside the battery panel. Alternatively, the protection units may be arranged side by side in the left-right direction on the bottom shelf plate inside the battery panel, or each protection unit corresponding to each bank may be arranged at the left-right end inside the battery panel (the electromagnetic contactor 110 in FIG. 3 may be arranged inside the battery panel). Furthermore, the protection units may be arranged vertically on the outer surface of the battery panel. These configurations allow for flexible adaptation to the installation environment of the power storage equipment (outside temperature, installation space, etc.).

[0044] 4: Communication equipment 10: Power storage equipment 11: Battery panel (housing) 12: Openable door 13: Shelf 20, 30: Management unit 100: Protection unit 102: Positive terminal connector 103: Negative terminal connector 105: External terminal connector 106: Service plug 110: Electromagnetic contactor 112: Fuse 115: LED board 117: Current sensor 119: LED 120: Communication bus 121: Communication line A: First bank A1, A2: First bank row B: Second bank B1, B2: Second bank row C: Third bank C1, C2: Third bank row D: Fourth bank D1, D2: Fourth bank row 1A: First bank 1A1, 1A2: First bank row 1B: Second bank 1B1, 1B2: Second bank row 1C: Third bank 1C1, 1C2: Third bank row 1D: Fourth bank 1D1, 1D2: Fourth bank row A01 to A16, B01 to A16 B16, C01 to C16, D01 to D16, ..., G01 to G16, H01 to H16: Storage module (storage element) L: Storage module L1: Control board

Claims

1. An energy storage facility comprising: a housing; a bank configured by a plurality of energy storage elements electrically connected in series; and a protection unit that opens and closes the power lines of the bank; the plurality of banks are housed in the housing; the plurality of banks include a first bank and a second bank arranged side by side in a vertical direction; the first bank has a first bank row in which the plurality of energy storage elements are arranged side by side in a direction intersecting the vertical direction; the second bank has a second bank row in which the plurality of energy storage elements are arranged side by side in a direction intersecting the vertical direction; and the first bank and the second bank are electrically connected in parallel.

2. The energy storage facility according to claim 1, wherein the first bank is arranged above the second bank, the first bank is configured to include a pair of first bank rows arranged side by side in the vertical direction, and the upper first bank row and the lower first bank row are electrically connected in series.

3. The power storage facility according to claim 1, wherein the first bank is disposed above the second bank, and the first bank is configured to include only one first bank row.

4. The energy storage facility according to any one of claims 1 to 3, wherein the housing includes a plurality of shelves therein, the energy storage element has an elongated shape extending from the front surface of the housing to the rear surface, and the energy storage element is inserted between a pair of shelves adjacent to each other in the vertical direction from the front of the housing.

5. The energy storage facility according to any one of claims 1 to 3, wherein the housing includes a plurality of shelves therein, the protection unit is placed on the top shelf in the housing, and the plurality of protection units are arranged side by side in a direction intersecting the vertical direction, and the plurality of protection units are provided corresponding to each of the plurality of banks.

6. A storage facility as described in any one of claims 1 to 3, wherein the storage element is provided on the front surface with a connector or terminal for electrical connection with an adjacent storage element or protection unit in a direction intersecting the vertical direction.

7. The energy storage facility according to any one of claims 1 to 3, comprising: a lower level management unit provided in each of the plurality of banks; and a higher level management unit that aggregates data acquired by the plurality of lower level management units.

8. The energy storage facility according to claim 7, wherein the lower-level management unit communicates with a control board built into each of the energy storage elements, and the lower-level management unit acquires temperature data measured in the energy storage elements and current data measured for each of the banks.

9. The power storage facility according to claim 8, wherein the lower level management unit executes management processing for detecting abnormalities in the communication state with the upper level management unit or the control board.

10. The power storage facility according to claim 7, further comprising a communication device, said communication device being connected to said upper level management unit and transmitting said status data via said upper level management unit.

11. The energy storage facility according to claim 7, comprising: a communication device; and a circuit breaker provided in each of the plurality of banks, wherein the communication device causes the lower-level management unit to open and close the circuit breaker.

12. The energy storage facility according to any one of claims 1 to 3, comprising: a lower-level management unit provided in each of the plurality of banks; and a circuit breaker provided in each of the plurality of banks, wherein the lower-level management unit opens and closes the circuit breaker so as to disconnect the bank having the highest temperature among the plurality of banks from the power line.

13. The energy storage facility according to any one of claims 1 to 3, further comprising a circuit breaker provided in each of the plurality of banks, wherein the protection unit opens and closes the circuit breaker so as to disconnect the bank having the highest temperature among the plurality of banks from the power line.

14. The energy storage facility according to any one of claims 1 to 3, comprising: a lower-level management unit provided in each of the plurality of banks; and a circuit breaker provided in each of the plurality of banks, wherein the lower-level management unit opens and closes the circuit breaker to disconnect the first bank from the power line when the temperature of the first bank, which is located at the top of the plurality of banks, is higher than that of the other banks.

15. The energy storage facility according to any one of claims 1 to 3, further comprising a circuit breaker provided in each of the plurality of banks, wherein the lower level management unit opens and closes the circuit breaker to disconnect the first bank from the power line when the temperature of the first bank, which is located at the top of the plurality of banks, is higher than that of the other banks.

16. A method for controlling an electric storage facility comprising: a housing; a bank configured by a plurality of storage elements electrically connected in series; and a protection unit that opens and closes a power line of the bank, wherein the plurality of banks are housed in the housing; the plurality of banks have a first bank and a second bank arranged side by side in a vertical direction; the first bank has a first bank row in which the plurality of storage elements are arranged side by side in a direction intersecting the vertical direction; the second bank has a second bank row in which the plurality of storage elements are arranged side by side in a direction intersecting the vertical direction; and the first bank and the second bank are electrically connected in parallel, wherein the method comprises disconnecting the bank with the highest temperature among the plurality of banks from the power line.

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