TWM640812U - Box-type battery energy storage system capable of detecting and reducing thermal event propagation - Google Patents

Abstract

A boxed battery energy storage system for detecting and reducing the propagation of thermal events includes a box body and at least one battery cabinet. The battery cabinet is arranged in the box body, and the battery cabinet includes a cabinet body, at least one battery module set in the cabinet body and a first control unit for controlling the battery module group. The battery module includes a casing, a plurality of battery cores, a vent valve, a pressure sensor, a temperature sensor and a fire extinguishing liquid delivery pipe. Wherein, after the battery module is activated, if the following conditions are met, the first control unit is triggered to shut down the battery module, and the fire extinguishing liquid delivery pipe is opened to allow a fire extinguishing liquid to be injected into the casing: The air pressure sensor determines that the air pressure is higher than a second air pressure threshold; and the temperature sensor determines that the temperature is higher than a temperature threshold.

Description

A packaged battery energy storage system that detects and reduces the propagation of thermal events

The present invention relates to a battery energy storage system, in particular to a boxed battery energy storage system that detects and reduces the propagation of thermal events.

With the rising awareness of environmental protection, the proportion of renewable energy is increasing, such as solar power, wind power and hydropower, etc. However, renewable energy is often affected by natural factors such as weather and seasons, and has the characteristics of intermittent power supply, resulting in unstable power supply However, it cannot be directly connected to the grid. In order to provide stable power to customers, energy storage equipment has become the main solution. Common energy storage equipment is Battery Energy Storage Systems (BESS).

The battery energy storage system uses multiple batteries in series to form a battery module, then connects multiple battery modules in series to form a battery cabinet, and finally connects multiple battery cabinets in parallel to form a battery energy storage system, which can be integrated into the grid and effectively To store electricity, common battery energy storage systems are composed of lithium batteries. However, when some abnormalities occur in lithium batteries, there is a chance to cause thermal runaway reaction and lead to large-scale fires. Thermal runaway is a common failure phenomenon of lithium batteries. It is a fire caused by the release of electrical energy and chemical energy in lithium batteries. Once the thermal runaway of the energy system occurs, the fire brigade can only spray water to cool down, wait for the electrical energy and chemical energy in the battery to be completely released, and must continue to spray water for several hours to prevent re-ignition. Therefore, thermal runaway not only poses safety concerns for the battery energy storage system , There is also the problem of occupying a large amount of firefighting resources.

A common solution to thermal runaway of battery energy storage systems is to inject liquid into the battery casing to reduce thermal runaway of the battery. For example, Chinese Invention Patent No. CN110947125B determines whether to inject liquid by judging one of the pressure signal or temperature signal. However, injecting liquid into the battery case is a destructive and irreversible cooling method. If only a single signal is used to judge, it is easy to cause system misjudgment and cause the risk of additional losses. Therefore, how to improve the thermal runaway problem of the battery energy storage system and reduce the risk of system misjudgment is a problem that those skilled in the art want to solve.

The main purpose of the present invention is to solve the problem that the conventional method of dealing with the thermal runaway of the battery energy storage system is to judge through a single signal and cause additional losses.

To achieve the above purpose, the present invention provides a boxed battery energy storage system for detecting and reducing the propagation of thermal events, which includes a box body and at least one battery cabinet. The battery cabinet is arranged in the box body, and the battery cabinet includes a cabinet body, at least one battery module set in the cabinet body and a first control unit for controlling the battery module group. The battery module includes a casing, a plurality of battery cells, a gas release valve, a pressure sensor, a temperature sensor and a fire extinguishing liquid delivery pipe, the casing defines a chamber, and the battery cells are electrically connected to each other And arranged in the chamber, the air release valve is arranged in an opening of the casing and allows the chamber to communicate with the outside when the air pressure in the chamber exceeds a first air pressure threshold, the air pressure sensor is configured for judging whether the air pressure of the chamber is higher than a second air pressure threshold, the second air pressure threshold is higher than the first air pressure threshold, and the temperature sensor is configured to judge whether the temperature of the chamber is higher than a temperature Threshold, the extinguishing fluid delivery conduit, communicates from a source of extinguishing fluid to the chamber. Wherein, after the battery module is started, if the following conditions are met, the first control unit is triggered to shutting off the battery module, and opening the fire extinguishing liquid delivery pipe to allow a fire extinguishing liquid to be injected into the chamber: the air pressure sensor judges that the air pressure in the chamber is higher than the second air pressure threshold; and the temperature sensor It is judged that the temperature of the chamber is higher than the temperature threshold.

To achieve the above purpose, the present invention also provides a packaged battery energy storage system for detecting and reducing the spread of thermal events, including a box body and at least one battery cabinet. The battery cabinet is arranged in the box body, and the battery cabinet includes a cabinet body, at least one battery module set in the cabinet body and a first control unit for controlling the battery module group. The battery module includes a housing, a plurality of battery cells, a gas release valve, a pressure sensor, a temperature sensor, a fire extinguishing liquid delivery pipe and a cooling device, the housing defines a chamber, the battery The cores are electrically connected to each other and arranged in the chamber, the air release valve is arranged in an opening of the housing and allows the chamber to communicate with the outside when the air pressure in the chamber exceeds a first air pressure threshold, and the air pressure sensor is configured to determine whether the air pressure of the chamber is higher than a second air pressure threshold, the second air pressure threshold is higher than the first air pressure threshold, and the temperature sensor is configured to determine whether the temperature of the chamber is Above a temperature threshold, the fire extinguishing liquid delivery pipe communicates from a source of fire extinguishing liquid to the chamber, the cooling device is arranged outside the housing and contacts the housing to cool the chamber, the cooling device has a first cooling mode and a second cooling mode, the cooling efficiency of the second cooling mode is greater than that of the first cooling mode. Wherein, after the battery module is activated, the cooling device operates in the first cooling mode, if the following conditions are met, the first control unit is triggered to shut down the battery module, and the fire extinguishing liquid delivery pipe is opened And a fire extinguishing liquid is injected into the chamber, and the cooling device is switched to the second cooling mode: the air pressure sensor judges that the air pressure in the chamber is higher than the second air pressure threshold; and the temperature sensor judges that the chamber The temperature of the chamber is above the temperature threshold.

Accordingly, the new box-type battery energy storage system of the present invention judges the air pressure and temperature in the chamber through the air pressure sensor and the temperature sensor to start the fire extinguishing procedure, and transports the fire extinguishing liquid through the fire extinguishing liquid delivery pipe. Extinguishing liquid into the chamber, and through the cooling device to cool the chamber room, to prevent the thermal runaway of the battery core from spreading to the battery cabinet and the boxed battery energy storage system. The fire extinguishing procedure will not be started until the judging conditions of the air pressure sensor and the temperature sensor are met, so that additional losses caused by a single sensor failure (or misjudgment) can be avoided.

1: Packed battery energy storage system

10: Box

20: battery cabinet

21: Cabinet

22: Battery module

221: shell

221a: upper shell

221b: lower shell

2211: chamber

2212: opening

222, 222a, 222b: battery cells

223: Discharge valve

224: Air pressure sensor

225: temperature sensor

226: Fire extinguishing liquid delivery pipe

2261: water injection valve

2262: fire extinguishing liquid

227:Second control unit

2271: box body

2272: Battery Monitor

228: cooling device

2281: Liquid inlet

2282: inner runner

2283: liquid outlet

23: The first control unit

231: Protection switch element

H: hot air

h: liquid level height

[Fig. 1] is a schematic structural diagram of a box-type battery energy storage system according to an embodiment of the present invention.

[FIG. 2A] is a schematic structural diagram of a battery module according to an embodiment of the present invention.

[FIG. 2B] is a schematic diagram of thermal runaway of a battery module according to an embodiment of the present invention.

[FIG. 2C] is a schematic diagram of the fire extinguishing process initiated by the battery module according to an embodiment of the present invention.

[FIG. 2D] is a step diagram of the battery module starting the fire extinguishing procedure according to an embodiment of the present invention.

[FIG. 3A] is a schematic diagram of the battery module starting fire extinguishing procedure according to another embodiment of the present invention.

[FIG. 3B] is a step diagram of the fire extinguishing procedure initiated by the battery module according to another embodiment of the present invention.

The terminology used herein is only for the purpose of describing specific embodiments and not limiting the present invention. As used herein, the singular forms "a" and "the" may also include plural forms unless the context dictates otherwise.

The directional terms used herein, such as up, down, left, right, front, back and their derivatives or synonyms, refer to the orientation of elements in the drawings and do not limit the present invention, unless the context clearly states otherwise. Relevant detailed description and technical content of the present invention are described as follows with respect to matching drawings now.

Refer to "Figure 1", which is a schematic structural diagram of the new box-type battery energy storage system. The present invention discloses a boxed battery energy storage system 1 for detecting and reducing the spread of thermal events, including a box body 10 and at least one battery cabinet 20 . In this embodiment, a plurality of battery cabinets 20 are arranged in parallel with each other inside the box body 10 to form a battery energy storage system (Battery Energy Storage Systems, BESS).

The battery cabinet 20 includes a cabinet body 21 , at least one battery module 22 and a first control unit 23 . The battery module 22 and the first control unit 23 are arranged in the cabinet 21. In this embodiment, the battery modules 22 are a plurality of connected in series and stacked in the cabinet 21. The first control unit 23 is arranged above the stacked battery modules 22 for controlling the stacked battery modules 22 connected in series. The first control unit 23 is a battery management system (Battery Management System, BMS) for detecting Measure and control the voltage, temperature, and current abnormal signals of the battery module 22 to avoid abnormal conditions such as over-discharge, over-charge, and over-temperature (operating temperature of the battery). The first control unit 23 includes a protection switch element 231, which can control the high-voltage DC output circuit of the battery cabinet 20.

Referring to "FIG. 2A" and "2B", it is a schematic structural diagram of a battery module according to an embodiment of the present invention and a schematic diagram of thermal runaway of the battery module. Further explaining the internal structure of the battery module 22, the battery module 22 includes a housing 221, a plurality of battery cells 222, a vent valve 223, a pressure sensor 224, a temperature sensor 225, a fire extinguishing liquid The delivery tube 226 and a second control unit 227 . In the operating state, the normal operating temperature range of the battery module 22 is between 0°C and 50°C when charging, and between -20°C and 60°C when discharging, and the pressure inside the battery module 22 is about 1atm (101kPa).

The casing 221 includes an upper casing 221a and a lower casing 221b, the upper casing 221a and the lower casing 221b define a chamber 2211, the chamber 2211 is a closed space, and the battery core 222 is arranged in the chamber 2211, the battery core 222 is electrically connected to each other through a plurality of series guides and a plurality of insulating spacers Force connection (such as series connection). When one or more of the battery cores 222 reaches the critical temperature of thermal runaway (as shown in FIG. 2B ), the battery core 222a that has thermal runaway will emit a hot gas H to the battery. Inside the module 22, the air pressure and temperature in the chamber 2211 rise sharply, and the battery core 222a where thermal runaway occurs will affect the adjacent battery core 222b, causing the thermal runaway situation to spread to the entire battery module. twenty two.

The air release valve 223 is disposed on an opening 2212 of the housing 221. When the air pressure in the chamber 2211 exceeds a first air pressure threshold, the air release valve 223 will be opened to allow the chamber 2211 to communicate with the outside. When the air pressure in the chamber 2211 exceeds the first air pressure threshold, the hot gas H in the chamber 2211 will be discharged from the vent valve 223, so as to prevent the chamber 2211 from being too high to cause the risk of explosion. In this embodiment, the opening 2212 is located at a top of the upper casing 221a, which is beneficial for the air release valve 223 to discharge the hot gas H quickly.

The air pressure sensor 224 is disposed on the upper casing 221a to detect the air pressure in the chamber 2211 and determine whether the air pressure exceeds a second air pressure threshold. Wherein, the second air pressure threshold is higher than the first air pressure threshold, the first air pressure threshold is between 102 kPa to 124 kPa, and the second air pressure threshold is between 125 kPa to 400 kPa.

The temperature sensor 225 is disposed on the upper housing 221a to detect the temperature in the chamber 2211 and determine whether the temperature is higher than a temperature threshold, and the temperature threshold is between 90°C and 350°C. In this embodiment, the temperature sensor 225 is installed at an outlet of the air release valve 223 to effectively detect a temperature of the hot gas H ejected from the air release valve 223 . The fire extinguishing liquid delivery pipe 226 communicates from a fire extinguishing liquid source to the chamber 2211 and is equipped with a water injection valve 2261, and the fire extinguishing liquid delivery pipe 226 is arranged on the upper casing 221a, and can quickly supply a fire extinguishing liquid 2262 into the chamber. Housing 221 . In one embodiment, the fire extinguishing liquid 2262 can be pure water, tap water, ethylene glycol, a mixture of ethylene glycol and water, silicon oil, silicon heat conduction oil or insulating oil.

The second control unit 227 is disposed outside the chamber 2211 and fixed on the housing 221. The second control unit 227 is electrically connected to the battery core 222. The second control unit 227 includes a box body 2271 and a The battery monitor 2272, the box body 2271 is independently arranged outside the housing 221, the battery monitor 2272 is installed in the box body 2271 and electrically connected to the battery core 222 for detecting the battery core 222 voltage and temperature, wherein the battery monitor 2272 is a cell monitor unit (Cell Monitor Unit, CMU). Both the box body 2271 and the casing 221 are closed spaces, which can prevent the fire extinguishing liquid 2262 from overflowing from the casing 221 to the box body 2271, thereby preventing the first control unit 23 from starting the fire extinguishing procedure to make the When the fire extinguishing liquid 2262 is injected into the chamber 2211 , the fire extinguishing liquid 2262 overflows from the casing 221 to the box body 2271 and the battery monitor 2272 is damaged.

On the other hand, the air release valve 223, the air pressure sensor 224, the temperature sensor 225 and the fire extinguishing liquid delivery pipe 226 are all arranged on the upper casing 221a (the upper half of the casing 221), which can Prevent the fire extinguishing liquid 2262 from affecting the functions of the air release valve 223 , the air pressure sensor 224 , the temperature sensor 225 and the fire extinguishing liquid delivery pipe 226 during the fire extinguishing procedure.

Referring to "FIG. 2C" and "FIG. 2D", it is a schematic diagram and a step-by-step diagram of the fire extinguishing procedure of the battery module according to an embodiment of the present invention. To further illustrate how the new box-type battery energy storage system reduces the propagation of thermal events, this embodiment performs the following steps:

Step S1: The first control unit 23 (i.e. battery management system, BMS) detects that the voltage, temperature, and current of the plurality of battery cells 222 of the battery module 22 send abnormal signals (over-discharge, over-charge, over-temperature Wait for the abnormal situation to occur), and then directly execute step S3.

Step S2: Step S2 is an operation procedure independent of Step S1. After the battery module 22 is activated, the air pressure and temperature in the chamber 2211 are detected by the air pressure sensor 224 and the temperature sensor 225 . Wherein, step S2 can be divided into steps S2-1 and S2-2, and the order of steps S2-1 and S2-2 can be reversed.

Step S2-1: The air pressure sensor 224 detects the air pressure in the chamber 2211, and determines that the air pressure in the chamber 2211 is higher than the second air pressure threshold. Then execute step 2-2.

Step S2-2: The temperature sensor 225 detects the temperature in the chamber 2211, and determines that the temperature in the chamber 2211 is higher than the temperature threshold. Then step S3 is executed.

Step S3: The protection switch element 231 of the first control unit 23 is triggered to turn off the battery module 22, so as to close the high voltage DC output circuit of the battery cabinet 20. Then step S4 is executed.

Step S4: The first control unit 23 controls the water injection valve 2261 to open to let the fire extinguishing liquid 2262 inject the fire extinguishing liquid 2262 into the chamber 2211 from the fire extinguishing liquid delivery pipe 226 until a liquid level h of the fire extinguishing liquid 2262 reaches the battery cell 222 between 50% and 95% of the first height. Then step S6 is executed immediately.

Step S6: The first control unit 23 notifies the external fire protection system, activates the fire alarm of the battery cabinet, and clears the relevant units. Further, the judgment conditions of the air pressure sensor 224 and the temperature sensor 225 must be satisfied at the same time (that is, the air pressure is higher than the second air pressure threshold and the temperature is greater than the temperature threshold), and the fire extinguishing procedure will be triggered, so that the water injection The valve 2261 is opened to allow the fire extinguishing liquid 2262 to be injected into the chamber 2211. Since the battery module 22 is injected into the fire extinguishing liquid 2262 is a destructive protection mechanism, the air pressure sensor 224 and the temperature sensor 225 The dual judgment conditions can avoid additional loss due to misjudgment by one of the air pressure sensor 224 and the temperature sensor 225 . In addition, the present model controls the thermal runaway range of the battery core 222 within one battery module 22, which can effectively prevent the thermal runaway from spreading to the entire battery cabinet 20 or the boxed battery energy storage system 1, greatly reducing the energy consumption of the battery cell 222. The loss caused by thermal runaway of the battery core 222 . In this embodiment, the opening and closing of the water filling valve 2261 is controlled by the first control unit 23 , and in other embodiments, the opening and closing of the water filling valve 2261 can be controlled by the air pressure sensor 224 .

Referring to "FIG. 3A", it is a schematic diagram of the battery module starting the fire extinguishing procedure according to another embodiment of the present invention. In this embodiment, the battery module 22 is further provided with a cooling device 228, the cooling device 228 is disposed outside the housing 221 and located below the housing 221 in a contacting manner. The cooling device 228 has a first cooling mode and a second cooling mode. When the battery module 22 is in a normal state, the cooling device 228 is in In the first cooling mode, the cooling efficiency of the second cooling mode is greater than that of the first cooling mode. The cooling device 228 includes a liquid inlet 2281, an inner flow channel 2282, and a liquid outlet 2283. The cooling device 228 provides a cooling liquid through a heat exchange system (not shown in the figure) to enter from the liquid inlet and flow through the shell. The inner channel 2282 in contact with the body 221 performs heat exchange, and then flows out from the liquid outlet 2283, and the cooling liquid returns to the heat exchange system for heat exchange and recycling. The cooling liquid can be pure water, ethylene glycol and water mixture. In other examples, the cooling device 228 not only has the function of cooling, but the cooling device 228 can be a cooling/heating unit to provide the temperature regulation of the battery core 222 when the battery module 22 is in normal operation, and the cooling liquid can also be Provides thermal energy to regulate temperature.

Further referring to "Fig. 3B", this embodiment is based on the operation state of the previous embodiment, and the cooling device 228 is additionally added to adjust the temperature, and the first control unit 23 controls the opening of the water injection valve 2261 to allow the fire extinguishing liquid After 2262 is injected into the chamber 2211 (that is, step S4), step S5 is performed first, followed by step S6 immediately.

Step S5: the first control unit 23 controls the heat exchange system to accelerate the supply of the cooling liquid into the cooling device 228, so that the cooling device 228 switches from the first cooling mode to the second cooling mode, and the accelerated cooling is located in the chamber The fire extinguishing liquid 2262 in the 2211 can achieve the maximum cooling effect and further reduce the risk of thermal runaway spread of the battery core 222.

In summary, the present invention detects the air pressure and temperature in the chamber of the battery module through the air pressure sensor and the temperature sensor, and decides whether to inject the fire extinguishing liquid into the chamber based on the judgment result. To prevent the thermal runaway of the battery module from spreading to the entire battery cabinet and affect the operation of the boxed battery energy storage system, and to control the loss caused by the thermal runaway of the battery core within a single In this battery module, large-scale electrical fires can also be avoided. Wherein, the judging conditions of the air pressure sensor and the temperature sensor must be satisfied at the same time, so as to trigger the opening of the fire extinguishing liquid delivery pipe and provide the fire extinguishing liquid into the chamber, which can avoid the air pressure sensor and the temperature sensor One of the detectors misjudged and caused additional losses.

22: Battery module

221a: upper shell

221b: lower shell

2211: chamber

2212: opening

222: battery cell

223: Discharge valve

224: Air pressure sensor

225: temperature sensor

226: Fire extinguishing liquid delivery pipe

2261: water injection valve

2262: fire extinguishing liquid

227:Second control unit

2271: box body

2272: Battery Monitor

h: liquid level height

Claims (10)

A packaged battery energy storage system for detecting and reducing the propagation of thermal events, comprising: a box; and At least one battery cabinet is arranged in the box, the battery cabinet includes a cabinet, at least one battery module set in the cabinet and a first control unit for controlling the battery module, the battery module Groups include: a housing defining a chamber; a plurality of battery cells electrically connected to each other and disposed in the chamber; a gas release valve, arranged at an opening of the housing and allowing the chamber to communicate with the outside when the air pressure in the chamber exceeds a first air pressure threshold; an air pressure sensor configured to determine whether the air pressure in the chamber is higher than a second air pressure threshold, and the second air pressure threshold is higher than the first air pressure threshold; a temperature sensor configured to determine whether the temperature of the chamber is higher than a temperature threshold; and an extinguishing fluid delivery pipe leading from a source of extinguishing fluid to the chamber; Wherein, after the battery module is activated, if the following conditions are met, the first control unit is triggered to shut down the battery module, and the fire extinguishing liquid delivery pipe is opened to allow a fire extinguishing liquid to be injected into the chamber: The air pressure sensor judges that the air pressure of the chamber is higher than the second air pressure threshold; and The temperature sensor determines that the temperature of the chamber is higher than the temperature threshold. The system according to claim 1, wherein the air pressure sensor, the temperature sensor, the air release valve and the fire extinguishing liquid delivery pipe are arranged on an upper half of the casing. The system according to claim 1, wherein the second air pressure threshold is between 125kPa to 400kPa, and the temperature threshold is between 90°C to 350°C. The system of claim 1, wherein the fire extinguishing liquid is injected into the chamber until a liquid level of the fire extinguishing liquid is between 50% and 95% of a height of the battery cell. The system according to claim 1, wherein the battery module further includes a second control unit disposed outside the chamber and fixed on the casing, the second control unit is electrically connected to the battery core. A packaged battery energy storage system for detecting and reducing the propagation of thermal events, comprising: a box; and At least one battery cabinet is set inside the box, the battery cabinet includes a frame, at least one battery module set on the frame and a first control unit for controlling the battery module, the battery Mods include: a housing defining a chamber; a plurality of battery cells electrically connected to each other and disposed in the chamber; a gas release valve, arranged at an opening of the housing and allowing the chamber to communicate with the outside when the air pressure in the chamber exceeds a first air pressure threshold; an air pressure sensor configured to determine whether the air pressure in the chamber is higher than a second air pressure threshold, and the second air pressure threshold is higher than the first air pressure threshold; a temperature sensor configured to determine whether the temperature of the chamber is higher than a temperature threshold; an extinguishing fluid delivery pipe communicating from a source of extinguishing fluid to the chamber; and A cooling device is arranged outside the casing and contacts the casing to cool the chamber, the cooling device has a first cooling mode and a second cooling mode, the cooling efficiency of the second cooling mode is greater than that of the first cooling mode ; Wherein, after the battery module is activated, the cooling device operates in the first cooling mode, if the following conditions are met, the first control unit is triggered to shut down the battery module, and the fire extinguishing liquid delivery pipe is opened and injecting an extinguishing liquid into the chamber, and switching the cooling device to the second cooling mode: The air pressure sensor judges that the air pressure of the chamber is higher than the second air pressure threshold; and The temperature sensor determines that the temperature of the chamber is higher than the temperature threshold. The system according to claim 6, wherein the air pressure sensor, the temperature sensor, the air release valve and the fire extinguishing liquid delivery pipe are arranged on an upper half of the casing. The system according to claim 6, wherein the air pressure threshold is between 125kPa and 400kPa, and the temperature threshold is between 90°C and 350°C. The system of claim 6, wherein the fire extinguishing liquid is injected into the chamber until a liquid level of the fire extinguishing liquid is between 50% and 95% of a height of the battery cell. The system according to claim 6, wherein the battery module further includes a second control unit disposed outside the chamber and fixed on the casing, the second control unit is electrically connected to the battery core.

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