Energy storage system

Abstract

The utility model provides an energy storage system which mainly solves the problem that potential safety hazards exist in smoke discharge due to thermal runaway of existing energy storage equipment. The energy storage system comprises at least two energy storage devices, wherein each energy storage device comprises an energy storage box body, a flue gas collecting pipe, a buffer device and at least one battery module; the battery module is arranged in the energy storage box body; thermal runaway flue gas generated by the battery module is conveyed to the buffer device through the flue gas collecting pipe; and the buffer device comprises at least one buffer tank for carrying out buffer treatment on the thermal runaway flue gas. According to the buffer tank, the thermal runaway flue gas is subjected to buffer treatment, so that the thermal runaway flue gas is smoothly discharged at a relatively stable flow speed, and meanwhile, electrolyte and impurities carried in the thermal runaway flue gas can be collected by the buffer tank, so that the thermal runaway flue gas subjected to buffer treatment cannot block a subsequent pipeline, and the service life of the thermal runaway flue gas is prolonged. Meanwhile, the treatment effect of a subsequent flue gas treatment device is also improved.

Description

Technical Field

[0001] The utility model belongs to the field of energy storage batteries, and particularly relates to an energy storage system. Background Art

[0002] With the development of new energy such as solar energy and wind energy, energy storage technology has also developed. Due to the advantages of high energy, long service life, high rated voltage, high power tolerance, and low self-discharge rate of lithium batteries, they have gradually become the mainstream products for energy storage.

[0003] With the large-scale application of lithium battery energy storage systems, the safe use of lithium batteries has also attracted attention. Since the batteries in energy storage devices are highly concentrated, under the influence of factors such as overcharging, over-discharging, overheating, and mechanical collision of the batteries, it is easy to cause the breakdown of the battery diaphragm and internal short circuit, resulting in thermal runaway.

[0004] When the lithium battery is completely out of control thermally, the internal temperature of the battery is as high as 500 - 1000 °C. The gas generated during the thermal runaway process causes the internal pressure of the battery to increase, making the battery case expand and rupture. Eventually, the explosion relief membrane opens, spraying and releasing the electrolyte and reaction gas evaporated and vaporized inside the battery, forming a pressurized thermal runaway flue gas. This thermal runaway flue gas not only includes gases such as carbon dioxide, hydrogen, carbon monoxide, and methane, but also includes impurities such as electrolyte and high-temperature molten plastic parts. When discharging the above thermal runaway flue gas, the electrolyte and impurities in the thermal runaway flue gas will affect the discharge of the thermal runaway flue gas, causing potential safety hazards. Summary of the Invention

[0005] To solve the problem of potential safety hazards in the discharge of thermal runaway flue gas from existing energy storage devices, the utility model provides an energy storage system.

[0006] To achieve the above purpose, the technical solution of the utility model is as follows:

[0007] An energy storage system includes at least two energy storage devices. Each energy storage device includes an energy storage box body, a flue gas manifold, a buffer device, and at least one battery module; the battery module is arranged in the energy storage box body; the thermal runaway flue gas generated by each battery module is transported to the buffer device through the flue gas manifold; the buffer device includes at least one buffer tank for buffering and processing the thermal runaway flue gas.

[0008] Further, the battery module includes a plurality of single cells, and the inner cavities of each single cell are connected to at least one shared chamber.

[0009] Further, the battery module includes a housing and a plurality of single cells arranged in the housing in the same direction; the housing is provided with a shared chamber, and the inner cavity of the shared chamber communicates with the inner cavities of all the single cells; avoidance holes are provided on the top plate of the housing corresponding to the polarity terminals of each single cell; the polarity terminals of each single cell extend out of the avoidance holes, and the area of the top plate of the housing corresponding to the avoidance holes is fixedly sealed with the housing of the single cell.

[0010] Further, the shared chamber includes at least one of an electrolyte shared chamber and a gas shared chamber; the electrolyte shared chamber communicates with the electrolyte regions of each single cell, and the gas shared chamber communicates with the gas regions of each single cell.

[0011] Further, the shared chamber includes an electrolyte shared chamber and a gas shared chamber. The electrolyte shared chamber communicates with the electrolyte regions of each single cell, and the gas shared chamber is a gas passage located between the top plate of the housing and each single cell. The gas passage covers the explosion vent part of each single cell. When the explosion vent part of any single cell is broken through by the hot runaway flue gas in the inner cavity, the gas region of the single cell communicates with the gas passage.

[0012] Further, the flue gas manifold includes a primary manifold and a secondary manifold. The primary manifold is connected to the battery modules arranged in the same row, and the secondary manifold is connected to each primary manifold to centrally transport the hot runaway flue gas in each primary manifold to the buffer tank.

[0013] Further, a vent pipe assembly communicating with the shared chamber is provided on the battery module; the vent pipe assembly includes a first vent member and a second vent member; the first vent member includes a first hollow pipe fitting connected to the housing, and a vent membrane is provided in the first hollow pipe fitting; the second vent member is a three-way pipe, its first interface is hermetically connected to the first vent member, and the second interfaces and third interfaces of the second vent members of adjacent two battery modules are connected by a flexible pipe section to form a primary manifold.

[0014] Further, the first vent member further includes a second hollow pipe fitting connected to the first hollow pipe fitting; the material of the second hollow pipe fitting is an insulating material, the second vent member is a union three-way pipe, and the union joint of the second vent member is threadedly connected to the second hollow pipe fitting.

[0015] Further, the buffer tank is provided with a smoke inlet and a smoke outlet communicating with its inner cavity. The smoke inlet and smoke outlet of the buffer tank are both provided at the top of the buffer tank, a drain valve is provided at the bottom of the buffer tank, and the buffer device is arranged in the energy storage box body.

[0016] Further, it further includes a flue gas conveying pipeline; the flue gas conveying pipeline includes a main flue gas pipeline and a plurality of branch flue gas pipelines, and each branch flue gas pipeline is respectively used for connecting with the buffer device of each energy storage device, and is used for conveying the thermal runaway flue gas buffered by the buffer device of each energy storage device into the main flue gas pipeline; the main flue gas pipeline centrally discharges the thermal runaway flue gas buffered by a plurality of energy storage device buffer devices.

[0017] Further, a flue gas treatment device is provided at the outlet of the main flue gas pipeline, and the flue gas treatment device includes at least one of a liquid treatment device, a solid treatment device, a flue gas cooling device, and an ignition device, and is used for centrally treating the thermal runaway flue gas buffered by a plurality of energy storage device buffer devices.

[0018] Further, the liquid treatment device includes M liquid treatment tanks, each liquid treatment tank is provided with a flue gas inlet and a flue gas outlet, the first to the (M - 1)th liquid treatment tanks are filled with a liquid treatment medium, and the Mth liquid treatment tank is an empty tank, where M is an integer greater than or equal to 2, the liquid treatment medium is an alkali solution, and the alkali solution is a 0.05 - 0.5 mol / L NaOH solution.

[0019] Further, the flue gas treatment device includes a liquid treatment device and an ignition device; the ignition device is connected to the flue gas outlet of the Mth liquid treatment tank and is used for igniting the thermal runaway flue gas treated by the liquid treatment device.

[0020] Further, a one - way valve for enabling the thermal runaway flue gas to flow unidirectionally is provided on the branch flue gas pipeline, and at the same time, a suction device for sucking the thermal runaway flue gas is provided on the branch flue gas pipeline, and the flue gas treatment device is arranged in an empty energy storage box body.

[0021] Compared with the prior art, the technical solution of the present utility model has the following advantages:

[0022] 1. The energy storage system of the present utility model includes at least two energy storage devices, and each energy storage device includes an energy storage box body, a flue gas confluence pipe, a buffer device, and a battery module. The flue gas confluence pipe is used for conveying the thermal runaway flue gas generated by each battery module to the buffer device; the buffer device includes at least one buffer tank, which not only buffers the thermal runaway flue gas, enabling the thermal runaway flue gas to be discharged smoothly at a relatively stable flow rate, but also can collect the electrolyte and impurities carried in the thermal runaway flue gas, so that the thermal runaway flue gas after buffer treatment will not block the subsequent pipeline, and at the same time, the treatment effect of the subsequent flue gas treatment device is improved.

[0023] 2. In the energy storage system of the present utility model, the battery module places multiple single cells in a housing with a shared chamber. By making the shared chamber communicate with the inner cavities of the individual cells located within the housing, the differences between the individual cells are reduced, and the consistency among the individual cells is improved to a certain extent, thereby improving the cycle life of the battery module to a certain extent.

[0024] 3. In the energy storage system of the present utility model, the shared chamber includes at least one of an electrolyte shared chamber and a gas shared chamber; the electrolyte shared chamber communicates with the electrolyte regions of the inner cavities of the individual cells. By making the electrolyte shared chamber communicate with the electrolyte regions of the inner cavities of the individual cells located within the housing, the electrolytes of the individual cells are shared to ensure the consistency of the individual cells, thereby improving the cycle life of the battery module to a certain extent. The gas shared chamber communicates with the gas regions of the inner cavities of the individual cells. By making the gas shared chamber communicate with the gas regions of the inner cavities of the individual cells located within the housing, the gas balance of the individual cells is achieved, and the consistency among the individual cells is improved to a certain extent, thereby improving the cycle life of the battery module to a certain extent.

[0025] 4. In the energy storage system of the present utility model, the shared chamber includes an electrolyte shared chamber and a gas shared chamber; the electrolyte shared chamber communicates with the electrolyte regions of the individual cells, and the gas shared chamber is a gas passage located between the top plate of the housing and the individual cells. This gas passage serves as a shared explosion relief passage. When the explosion relief part of any single cell is broken through by the flue gas in the inner cavity, the thermal runaway flue gas in the inner cavity of this single cell is discharged through the gas passage, improving the safety of the battery module.

[0026] 5. In the energy storage system of the present utility model, the flue gas manifold includes a primary manifold and a secondary manifold. The flue gas manifold collects the thermal runaway flue gas of all battery modules. When thermal runaway occurs in a single cell within any battery module, its thermal runaway flue gas can be discharged through the flue gas manifold, reducing the risk of thermal runaway spread.

[0027] 6. In the energy storage system of the present utility model, the explosion relief pipe assembly of the battery module is designed as a three-way pipe section. The flexible pipe section is used to connect the three-way pipe sections of adjacent battery modules to form a primary manifold. Compared with the flue gas manifold using an integral pipe structure, the installation accuracy requirements for the explosion relief pipe assemblies of each battery module are relatively small. The installation deviation of the explosion relief pipe assembly can be compensated by the deformation of the flexible pipe section, reducing the installation difficulty of the flue gas manifold.

[0028] 7. In the energy storage system of the present utility model, the smoke inlet of the buffer tank is arranged at the top of the buffer tank, which can make the impurities and electrolyte carried by the thermal runaway smoke deposit at the bottom of the buffer tank under the action of gravity. At the same time, the smoke outlet of the buffer tank is arranged at the top of the buffer tank. First, it can prevent the impurities and electrolyte carried by the thermal runaway smoke from being discharged from the buffer tank. Second, it enables the gas in the thermal runaway smoke to be discharged smoothly and quickly. In addition, a drain valve is arranged at the bottom of the buffer tank, and the drain valve can timely discharge the electrolyte and impurities in the buffer tank.

[0029] 8. In the energy storage system of the present utility model, the buffer device is arranged inside the energy storage box. This arrangement can not only protect the buffer device and increase its service life, but also enhance the aesthetics of the energy storage device and facilitate the integration of the energy storage device.

[0030] 9. The energy storage system of the present utility model includes a smoke transmission pipeline, which centrally discharges the thermal runaway smoke after being buffered by the buffer device in multiple energy storage devices in the energy storage system to the outside of each energy storage device for treatment, avoiding affecting the battery modules inside the energy storage devices.

[0031] 10. In the energy storage system of the present utility model, a smoke treatment device is provided at the outlet of the main smoke pipeline. The smoke treatment device treats the thermal runaway smoke generated by multiple energy storage devices in various ways to avoid potential safety hazards caused by the discharge of the thermal runaway smoke. At the same time, the smoke treatment device is used to centrally treat the thermal runaway smoke buffered by the buffer devices of multiple energy storage devices. Multiple energy storage devices share one smoke treatment device, which not only improves the safety of the energy storage device during use but also significantly reduces the manufacturing cost of the entire energy storage system.

[0032] 11. In the energy storage system of the present utility model, the liquid treatment device includes M liquid treatment tanks. The first to the (M - 1)th liquid treatment tanks are filled with liquid treatment media to effectively treat the thermal runaway smoke. At the same time, the Mth liquid treatment tank of the liquid treatment device is an empty tank. When the pressure of the thermal runaway smoke is too high, the empty tank can collect the liquid treatment media extruded from the liquid treatment tank by the high-pressure thermal runaway smoke, preventing the liquid treatment media from being extruded out of the liquid treatment tank and affecting the subsequent devices.

[0033] 12. In the energy storage system of the present utility model, the smoke treatment device includes a liquid treatment device and an ignition device. The ignition device performs a controllable ignition treatment on the thermal runaway smoke treated by the liquid treatment device, and the thermal runaway smoke after ignition treatment can be directly discharged without potential hazards such as combustion and explosion.

[0034] 13. In the energy storage system of the present utility model, the liquid treatment medium is an alkaline solution. This alkaline solution can not only fully treat the electrolyte carried in the thermal runaway flue gas to prevent the vaporized electrolyte from continuing to decompose and generate combustible gases. At the same time, this alkaline solution can also treat some gases in the thermal runaway flue gas, and the gas volume of the thermal runaway flue gas treated by the alkaline solution is greatly reduced. Among them, the treatment effect of the thermal runaway flue gas with a 0.05 - 0.5 mol / L NaOH solution is relatively prominent.

[0035] 14. In the energy storage system of the present utility model, a one - way valve for the unidirectional flow of thermal runaway flue gas is provided on the flue gas branch pipeline. This one - way valve can prevent the thermal runaway flue gas in the main flue gas pipeline from entering the energy storage device that has not experienced thermal runaway, improving the safety of the energy storage system. At the same time, a suction device is provided on the flue gas branch pipeline. The suction device actively sucks the thermal runaway flue gas in the energy storage device into the main flue gas pipeline in a timely manner, avoiding the influence of the thermal runaway flue gas generated by the thermal runaway battery module in the energy storage device on the battery modules that have not experienced thermal runaway, and improving the safety of the energy storage device.

[0036] 15. In the energy storage system of the present utility model, the flue gas treatment device is arranged in an empty energy storage box body. The energy storage box body can provide safety protection for the flue gas treatment device, increasing its service life. At the same time, this setting makes the entire energy storage system convenient for standardization and modularization, facilitating on - site management and maintenance, and also having aesthetics. Description of the Drawings

[0037] Figure 1 Schematic diagram of the energy storage device in Embodiment 1;

[0038] Figure 2 Schematic diagram of the structure of the battery module in Embodiment 1;

[0039] Figure 3 Schematic diagram of the connection between each battery module and the first - level busbar (integral pipe) in Embodiment 1;

[0040] Figure 4 Schematic diagram of the connection between each battery module and the first - level busbar (spliced pipe) in Embodiment 1;

[0041] Figure 5 Partial explosion diagram of the connection between each battery module and the first - level busbar in Embodiment 1;

[0042] Figure 6 Explosion diagram of the explosion vent pipe assembly in Embodiment 1 Figure 1 ;

[0043] Figure 7 Explosion diagram of the explosion vent pipe assembly in Embodiment 1 Figure 2 ;

[0044] Figure 8Schematic structural diagram of the buffer device in Embodiment 1;

[0045] Figure 9 Schematic diagram of the energy storage system in Embodiment 2;

[0046] Figure 10 Schematic diagram of the energy storage system in Embodiment 3;

[0047] Figure 11 Schematic structural diagram of the liquid treatment device in Embodiment 3;

[0048] Figure 12 Schematic structural diagram of the liquid treatment tank in Embodiment 3;

[0049] Figure 13 Schematic structural diagram of the flue gas treatment device in Embodiment 4;

[0050] Figure 14 Schematic structural diagram of the flue gas treatment device in Embodiment 5;

[0051] Figure 15 Schematic structural diagram of the flue gas treatment device in Embodiment 7;

[0052] Reference numerals: 1 - energy storage device, 2 - buffer device, 3 - flue gas pipeline, 4 - liquid treatment device, 5 - flue gas cooling device, 6 - ignition device, 7 - solid treatment device, 11 - battery module, 12 - energy storage box, 13 - flue gas manifold, 14 - explosion vent pipe assembly, 111 - outer shell, 112 - single cell, 113 - polar terminal, 114 - electrolyte sharing chamber, 115 - gas sharing chamber, 131 - primary manifold, 132 - secondary manifold, 1311 - flexible pipe section, 141 - first explosion vent member, 1411 - first hollow pipe fitting, 1412 - second hollow pipe fitting; 142 - second explosion vent member; 21 - buffer tank, 22 - flue gas inlet, 23 - flue gas outlet, 24 - drain valve, 31 - main flue gas pipeline, 32 - flue gas branch pipeline, 33 - check valve, 34 - suction device, 41 - liquid treatment tank, 42 - drain pipe, 43 - three-way valve, 44 - shunt section, 45 - spiral baffle, 51 - cooling treatment tank, 61 - flue gas pipeline, 62 - exhaust pipe, 63 - igniter, 64 - trigger, 65 - flame arrester, 71 - solid treatment tank. Detailed implementation manners

[0053] To make the above objects, features, and advantages of the present utility model more apparent and understandable, the following provides a detailed description of the specific embodiments of the present utility model with reference to the accompanying drawings of the specification. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of them. Based on the embodiments in the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present utility model.

[0054] In this specification, "in other embodiments" that appears in different places does not necessarily refer to the same embodiment, nor is it an independent or selectively mutually exclusive embodiment with other embodiments. In the description of this specification, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. In the description of the present utility model, "a plurality of" means two or more, unless otherwise specifically defined.

[0055] In the description of this specification, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, indirectly connected through an intermediate member, or the internal communication of two components. For those of ordinary skill in the art, the specific meaning of the above terms in the present utility model can be understood according to specific circumstances.

[0056] At the same time, in the description of the present utility model, it should be noted that the orientation or positional relationship indicated by terms such as "top, bottom, inner, and outer" is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation to the present utility model.

[0057] The present utility model provides an energy storage system, which includes at least two energy storage devices. Each energy storage device includes an energy storage box body and a plurality of battery modules arranged in the energy storage box body. The plurality of battery modules are connected in series, parallel, or in series-parallel to meet the capacity requirements of the energy storage device. At the same time, the energy storage device includes a buffer device for connecting with the flue gas converging pipe of each energy storage device, and the buffer device includes at least one buffer tank. Each buffer tank not only buffers the thermal runaway flue gas, enabling the thermal runaway flue gas to be discharged smoothly at a relatively stable flow rate, but also can collect part of the electrolyte and impurities carried in the thermal runaway flue gas, so that the treated thermal runaway flue gas will not block the subsequent pipeline, and at the same time, the treatment effect of the subsequent flue gas treatment device is improved.

[0058] Embodiment 1

[0059] As Figure 1As shown in the figure, this embodiment provides an energy storage system, which includes at least two energy storage devices. Each energy storage device 1 includes an energy storage box body 12, a flue gas manifold 13, a buffer device 2, and at least one battery module 11; the battery module 11 is arranged in the energy storage box body 12, and the number of battery modules 11 is set according to the requirements of the energy storage device. Multiple battery modules 11 are connected in series and parallel to meet the charging and discharging requirements. The flue gas manifold 13 is used to transport the thermal runaway flue gas generated by each battery module 11 to the buffer device 2; the buffer device 2 includes at least one buffer tank 21, and each buffer tank 21 is used to buffer the thermal runaway flue gas.

[0060] The battery module in the above energy storage device can be a single cell, a PACK, or a battery module. Specifically, the battery module is a large-capacity battery disclosed in Chinese patents CN117477186A, CN117477063A, and CN115275453A; such large-capacity batteries all include multiple single cells, and the inner cavities of each single cell are connected to at least one shared chamber. The shared chamber of this type of large-capacity battery is realized through at least one hollow member, and the hollow member can be composed of a hollow box body with one end open and a cover plate for covering the opening; the hollow box body is fixed on the upper cover plate, lower cover plate, or cylinder body of each single cell, and the inner cavities of each single cell communicate with the inner cavity of the hollow member, so that each single cell is in the same electrolyte system and gas balance system.

[0061] As Figure 2 shown in the figure, the battery module 11 in this embodiment includes a housing 111 and multiple single cells 112, and the multiple single cells 112 are arranged in the same direction and placed in the housing 111. The housing 111 is provided with a shared chamber, and the inner cavity of the shared chamber communicates with the inner cavities of all single cells 112. The single cells 112 in this embodiment are square shell batteries, and the number can be adjusted according to actual needs. The inner cavity of each single cell 112 includes an electrolyte area and a gas area.

[0062] As Figure 2 shown in the figure, after the multiple single cells 112 are arranged in the same direction and placed in the housing 111, avoidance holes are opened on the top plate of the housing 111 corresponding to the polarity terminals 113 of each single cell 112. The polarity terminals 113 of each single cell 112 extend out of the corresponding avoidance holes to serve as the polarity terminals of the battery module 11 (the polarity terminals 113 of all single cells 112 on one side serve as the positive polarity terminals of the battery module 11, and the polarity terminals 113 of all single cells 112 on the other side serve as the negative polarity terminals of the battery module 11). The area of the top plate of the housing 111 corresponding to the avoidance hole is fixedly sealed with the shell of the single cell 112, so that the gap between the polarity terminal 113 and the avoidance hole is sealed.

[0063] It should be noted that the polar terminal 113 of the single battery 112 here can be the terminal post of the single battery 112. If it is to avoid that the terminal post of the single battery 112 cannot smoothly extend out of the avoidance hole as the polar terminal 113, a terminal post adapter can also be connected to the terminal post of the single battery 112, and the overall structure formed by the cooperation of the terminal post of the single battery 112 and the terminal post adapter is used as the polar terminal 113 of the single battery 112.

[0064] The shared chamber in the above-mentioned housing 111 can be an electrolyte shared chamber 114. The electrolyte shared chamber 114 is a liquid channel provided on the bottom plate of the housing 111. The inner cavity of the electrolyte shared chamber 114 is communicated with the inner cavity electrolyte areas of all the single batteries 112. Through the electrolyte shared chamber 114, each single battery 112 can be in a unified electrolyte environment, ensuring the uniformity of the electrolyte in each single battery 112 and improving the performance and charge-discharge cycle life of the battery module 11.

[0065] The shared chamber in the above-mentioned housing 111 can be a gas shared chamber 115. The gas shared chamber 115 is a gas channel provided on the top plate of the housing 111. The inner cavity of the gas shared chamber 115 is communicated with the inner cavity gas areas of all the single batteries 112. Through the gas shared chamber 115, the gas balance of each single battery 112 can be achieved, and the performance and charge-discharge cycle life of the battery module 11 can also be improved.

[0066] The above-mentioned shared chamber can be a gas-liquid shared chamber. The inner cavity of the gas-liquid shared chamber is communicated with both the electrolyte area and the gas area in the inner cavities of all the single batteries 112. Through a gas-liquid shared chamber, each single battery 112 can be in a unified electrolyte environment and gas environment, improving the performance and charge-discharge cycle life of the battery module 11. Specifically, when setting, a protrusion extending along the arrangement direction of the single batteries 112 is provided on the side wall of the housing 111, and a gas-liquid shared chamber is formed at the protrusion part, and the gas-liquid shared chamber is communicated with both the electrolyte area and the gas area of each single battery 112.

[0067] The above-mentioned shared chamber can also include an electrolyte shared chamber 114 and a gas shared chamber 115 at the same time. The inner cavity of the electrolyte shared chamber 114 is communicated with the inner cavity electrolyte areas of all the single batteries 112, and the inner cavity of the gas shared chamber 115 is communicated with the inner cavity gas areas of all the single batteries 112. Placing a plurality of single batteries 112 inside a housing 111 having an electrolyte shared chamber 114 and a gas shared chamber 115 enables the electrolyte and gas of each single battery 112 to be shared to ensure the consistency of each single battery 112, making the electrolyte and gas of all the single batteries 112 in the same system, reducing the differences between each single battery 112, improving the consistency between each single battery 112 to a certain extent, and thus improving the cycle life of the battery module to a certain extent.

[0068] The above-mentioned shared chamber may also include an electrolyte shared chamber 114 and a gas shared chamber 115 at the same time. The inner cavity of the electrolyte shared chamber 114 is communicated with the electrolyte areas in the inner cavities of all the single cells 112. The gas shared chamber 115 is a gas passage located between the top plate of the outer shell 111 and each single cell 112. This gas passage covers the explosion relief parts (specifically, explosion relief membranes) of each single cell 112. When the explosion relief part of any single cell 112 is broken through by the hot runaway flue gas in the inner cavity, the gas area in the inner cavity of this single cell 112 is communicated with the gas passage. At this time, the gas shared chamber 115 is used as an explosion relief passage. That is, during the normal operation of the battery module 11, the inner cavities of each single cell 112 are not communicated with the gas passage. When any single cell 112 has a thermal runaway, when the explosion relief part at the top of this single cell 112 is opened by the flue gas in the inner cavity, the inner cavity of this single cell 112 is communicated with the gas passage, and the hot runaway flue gas is discharged through the gas passage, improving the safety of the battery module 11.

[0069] As Figure 1 shown, in order to prevent the hot runaway flue gas of individual battery modules 11 from spreading to the entire energy storage device 1 and causing safety problems, the hot runaway flue gases of all battery modules 11 are converged by the flue gas converging pipe 13. When a single cell 112 in any battery module 11 has a thermal runaway, its hot runaway flue gas can be discharged into the buffer device 2 through the flue gas converging pipe 13, reducing the spread of thermal runaway.

[0070] As Figure 1 、 Figure 3 and Figure 4 shown, the flue gas converging pipe 13 in this embodiment includes a primary converging pipe 131 and a secondary converging pipe 132. The primary converging pipe 131 is connected to the battery modules 11 arranged in the same row, and the secondary converging pipe 132 is connected to each primary converging pipe 131, converging the hot runaway flue gases generated by each battery module 11 into the buffer device 2. This Figure 3 and Figure 4 only exemplarily provides one row of battery modules 11. If there are multiple rows of battery modules 11, the battery modules 11 in each row are arranged in sequence from top to bottom. Each primary converging pipe 131 is connected to the secondary converging pipe 132, and the secondary converging pipe 132 centrally conveys the hot runaway flue gases in each primary converging pipe 131 to the buffer device 2.

[0071] As Figure 2As shown in the figure, in order to lead out the thermal runaway flue gas from each battery module 11, an explosion vent pipe assembly 14 communicating with the inner cavity of the outer shell 111 is provided on the outer shell 111 of each battery module 11; one end of the explosion vent pipe assembly 14 communicates with the shared chamber of the battery module 11, and the other end is connected to the first-stage manifold 131. Specifically, when connecting, the explosion vent pipe assembly 14 is arranged on the outer shell 111 and communicates with at least one of the electrolyte shared chamber 114 and the gas shared chamber 115. When both the electrolyte shared chamber 114 and the gas shared chamber 115 are communicated with the explosion vent pipe assembly 14, two sets of explosion vent pipe assemblies 14 are provided on the outer shell 111, and the two sets of explosion vent pipe assemblies 14 are respectively communicated with the electrolyte shared chamber 114 and the gas shared chamber 115. Subsequently, the two sets of explosion vent pipe assemblies 14 are both connected to the same first-stage manifold 131, or the two sets of explosion vent pipe assemblies 14 are respectively connected to different first-stage manifolds 131; this setting enables the battery module 11 to have two explosion vent channels. When any single battery 112 has a thermal runaway, the thermal runaway flue gas is discharged from different explosion vent channels, and the heat and thermal runaway flue gas accumulated in the explosion vent channels and the single battery 112 can be reduced in a short time, reducing the explosion risk.

[0072] The first-stage manifold 131 in this embodiment may specifically include the following structural forms.

[0073] First, as Figure 3 shown, a whole pipe can be selected as the first-stage manifold 131, and a plurality of branch pipes connected to the explosion vent pipe assemblies of each battery module 11 are provided thereon. At this time, the explosion vent pipe assembly 14 includes a first explosion vent member and a second explosion vent member; the first explosion vent member includes a first hollow pipe fitting with an explosion vent film inside, which is connected to the outer shell 111; the second explosion vent member is a flexible hollow pipe fitting, which is connected to the first explosion vent member 141. During assembly, first arrange all the battery modules 11 along the length direction of the first-stage manifold 131, and then connect the branch pipes of the first-stage manifold 131 to the second explosion vent members of the corresponding battery modules 11.

[0074] Second, as Figure 4 、 Figure 5 and Figure 6As shown, the explosion vent pipe assembly 14 is designed as a split part, and at the same time, the first-stage manifold 131 is also designed as a split part. The explosion vent pipe assembly 14 includes a first explosion vent member 141 and a second explosion vent member 142. The first explosion vent member 141 includes a first hollow pipe fitting 1411 with an explosion vent film inside, which is connected to the outer shell 111. The second explosion vent member 142 is a three-way pipe, whose first interface (vertical pipe section joint) is hermetically connected to the first explosion vent member 141, and the second interface and the third interface (two joints of the horizontal pipe section) are respectively used to connect to the flexible pipe sections 1311 that make up the first-stage manifold 131. That is to say, the first-stage manifold 131 is spliced by the horizontal pipe sections of multiple three-way pipes and multiple flexible pipe sections 1311. During assembly, each three-way pipe section is fixed on the corresponding first explosion vent member 141 to form a battery module 11 with an explosion vent pipe assembly 14. After that, multiple battery modules 11 are arranged in a set direction. Finally, the adjacent two three-way pipes are connected by the flexible pipe sections 1311. In this embodiment, due to the spliced first-stage manifold 131 and the middle connecting pipe section being a flexible pipe section 1311, the deformation of the flexible pipe section 1311 can compensate for the installation error of the explosion vent pipe assembly 14 and the spacing deviation of the battery modules 11, reducing the installation difficulty of the first-stage manifold 131.

[0075] To further improve safety, the first-stage manifold 131 and the battery module 11 should be insulated. For example, flexible pipe sections and / or three-way pipe sections made of insulating and high-temperature resistant (thermal runaway flue gas temperature) materials can be used, or an insulating pipe section can be added between the first hollow pipe fitting 1411 and the second explosion vent member 142. Specifically, as Figure 7 shown, the first explosion vent member 141 further includes a second hollow pipe fitting 1412 connected to the first hollow pipe fitting 1411. The material of the second hollow pipe fitting 1412 is an insulating material. The second explosion vent member 142 is a union three-way pipe, and the union joint of the second explosion vent member 142 is threadedly connected to the second hollow pipe fitting 1412.

[0076] When the explosion vent pipe assembly 14 with the explosion vent film is specifically connected, it is applicable to the shared chamber communicating with the inner cavities of each single battery 112. Specifically, it is the electrolyte shared chamber 114 communicating with the electrolyte areas of the inner cavities of all single batteries 112, or the gas shared chamber 115 communicating with the gas areas of the inner cavities of all single batteries 112.

[0077] When the gas sharing chamber 115 is a gas passage located between the top plate of the outer shell 111 and each single battery 112, and this gas passage serves as a shared explosion venting passage, the outer shell 111 is connected to the flue gas manifold 13 through a sealing connector. The sealing connector includes a sealing connecting pipe and a one-way valve or pressure valve etc. provided on the sealing connecting pipe. One end of the sealing connecting pipe is connected to the outer shell 111 and is in communication with the gas passage, and the other end is connected to the primary manifold 131. When the battery module 11 is operating normally, the sealing connector disconnects the gas passage from the primary manifold 131 to ensure that the inner cavity of the outer shell 111 is in a closed state. When the battery module 11 undergoes thermal runaway, when the explosion venting part of any single battery 112 is broken through by the hot gas in the inner cavity, the hot gas enters the gas passage. Subsequently, the hot gas opens the one-way valve or pressure valve, and the hot gas enters the flue gas manifold 13 through the gas passage.

[0078] In the energy storage device of this embodiment, multiple primary manifolds 131 are all connected to the secondary manifold 132, and the outlet of the secondary manifold 132 is connected to the buffer device 2. The primary manifold 131 and the secondary manifold 132 converge the hot gas generated by each battery module 11 and transport it to the buffer device 2. The buffer device 2 buffers the hot gas, thereby improving the safety of the entire energy storage device.

[0079] As Figure 8 shown, the buffer device 2 in this embodiment includes at least one buffer tank 21. Each buffer tank 21 is provided with a smoke inlet 22 and a smoke outlet 23 that communicate with its inner cavity. The number of buffer tanks 21 can be set according to the number and requirements of the battery modules 11 in the energy storage device 1. If there are multiple buffer tanks 21, the multiple buffer tanks 21 can be connected in series or in parallel through connecting pipelines. If the multiple buffer tanks 21 are connected in series, the smoke inlet 22 of the first buffer tank 21 is connected to the secondary manifold 132. The shape of the buffer tank 21 is not limited and can be a rectangular tank body, a circular tank body, an oval tank body, etc. Preferably, a circular tank body is used, and the circular tank body has good pressure-bearing performance.

[0080] An inlet port 22 and an outlet port 23 communicating with the inner cavity are provided on the above-mentioned buffer tank 21. The inlet port 22 is mainly used to convey the thermal runaway flue gas into the buffer tank 21, and the outlet port 23 is mainly used to discharge the thermal runaway flue gas in the buffer tank 21. When specifically setting the above-mentioned inlet port 22 and outlet port 23, they can be set on the side wall of the buffer tank 21 or on the top of the buffer tank 21. In this embodiment, both the inlet port 22 and the outlet port 23 are set on the top of the buffer tank 21. Setting the inlet port 22 on the top of the buffer tank 21 can enable impurities and electrolyte carried by the thermal runaway flue gas to be deposited at the bottom of the buffer tank 21 under the action of gravity; setting the outlet port 23 on the top of the buffer tank 21, on the one hand, can prevent impurities and electrolyte carried by the thermal runaway flue gas from being discharged smoothly, and on the other hand, can enable the gas in the thermal runaway flue gas to be discharged from the buffer tank 21 smoothly.

[0081] As Figure 8 shown, a drain valve 24 can also be provided at the bottom of the above-mentioned buffer tank 21 to timely discharge the electrolyte and impurities in the buffer tank 21.

[0082] In this embodiment, each buffer tank 21 is an empty tank body, and generally no substances are filled inside, and it has the following functions:

[0083] First, buffer the thermal runaway flue gas;

[0084] Each buffer tank 21 buffers the thermal runaway flue gas, slows down the speed of the thermal runaway flue gas, and reduces the pressure of the thermal runaway flue gas, so that the thermal runaway flue gas is discharged at a relatively stable flow rate. When the thermal runaway flue gas is discharged at a stable flow rate, the treatment effect of the subsequent flue gas treatment device can be improved;

[0085] Second, collect the electrolyte in the thermal runaway flue gas;

[0086] There is a certain amount of free electrolyte in the battery module 11 of the energy storage device 1. This free electrolyte is ejected together with the thermal runaway flue gas when the battery module 11 undergoes thermal runaway. Especially when the explosion vent area is set at the bottom of the battery module 11, almost all the free electrolyte inside the battery module 11 is ejected with the thermal runaway flue gas. While buffering the thermal runaway flue gas, the buffer tank 21 performs gas-liquid separation on the thermal runaway flue gas, so that the electrolyte carried in the thermal runaway flue gas is collected in the buffer tank 21. At this time, not only can the decomposition reaction of the vaporized electrolyte to generate combustible gas be prevented, reducing the amount of combustible gas, but also the use cost of the subsequent flue gas treatment device can be reduced;

[0087] Third, remove impurities from the thermal runaway flue gas;

[0088] When the battery module 11 undergoes thermal runaway, its internal temperature is generally about 500 - 1000 °C. At this temperature, fusible components such as diaphragms, plastic films, and plastic parts inside the battery module 11 are melted by the high temperature. The above-mentioned molten substances are ejected from the battery inner cavity along with the hot and high-pressure thermal runaway flue gas. During the transportation through the flue gas manifold 13, as the temperature of the thermal runaway flue gas decreases, the molten substances gradually solidify and agglomerate. At this time, by adding the above-mentioned buffer tank 21, impurities such as the molten matter discharged along with the thermal runaway flue gas will be deposited and collected in the buffer tank 21 when the thermal runaway flue gas buffers in the buffer tank 21, avoiding the blockage problem of the subsequent pipeline.

[0089] When the above-mentioned buffer device 2 is specifically installed, it can be installed inside the energy storage box 12 of the energy storage device 1, or outside the energy storage device 1. Preferably, the buffer device 2 is arranged inside the energy storage box 12 of the energy storage device 1. At this time, not only can the buffer device 2 be protected and its service life be increased, but also the aesthetics and integration of the energy storage device 1 can be improved.

[0090] Embodiment 2

[0091] As Figure 9 shown, this embodiment provides an energy storage system, which includes multiple energy storage devices 1 in Embodiment 1 and a flue gas transportation pipeline 3; the flue gas transportation pipeline 3 includes a main flue gas pipeline 31 and multiple branch flue gas pipelines 32. One end of each branch flue gas pipeline 32 is connected to the buffer device 2 of each energy storage device 1, and the other end is connected to the main flue gas pipeline 31, for transporting the thermal runaway flue gas after being buffered by the buffer device 2 of each energy storage device 1 into the main flue gas pipeline 31. Specifically, when connecting, one end of each branch flue gas pipeline 32 is respectively connected to the smoke outlet 23 of the last buffer tank 21. The main flue gas pipeline 31 centrally discharges the thermal runaway flue gas after being buffered by multiple energy storage devices 1. The flue gas transportation pipeline 3 centrally discharges the thermal runaway flue gas after being buffered by the buffer device 2 of each energy storage device 1 in the energy storage system outside the energy storage device 1 for treatment, avoiding the influence of the thermal runaway flue gas on the battery module 11 inside the energy storage device 1.

[0092] As Figure 9As shown in the figure, in the energy storage system of this embodiment, a one-way valve 33 for allowing the thermally runaway flue gas to flow unidirectionally may also be provided on the flue gas branch pipeline 32. After the one-way valve 33 is installed, the thermally runaway flue gas in the energy storage device 1 can flow through the flue gas branch pipeline 32 into the main flue gas pipeline 31, while the thermally runaway flue gas in the main flue gas pipeline 31 cannot flow through the flue gas branch pipeline 32 into the energy storage box 12. This one-way valve 33 prevents the thermally runaway flue gas in the main flue gas pipeline 31 from entering the energy storage device 1 that has not experienced thermal runaway, improving the safety of the energy storage system. In addition, a suction device 34 may also be provided on the above-mentioned flue gas branch pipeline 32. The suction device 34 may specifically adopt devices such as a suction fan. The suction device 34 actively sucks the thermally runaway flue gas in the energy storage device 1 out of the energy storage box 12 in a timely manner, preventing the thermally runaway flue gas in the energy storage box 12 from affecting the battery modules 11 that have not experienced thermal runaway, and further improving the safety of the energy storage device 1.

[0093] Embodiment 3

[0094] The energy storage system of this embodiment is similar to that of Embodiment 2. The difference is that the energy storage system of this embodiment further includes a flue gas treatment device, which is arranged at the outlet end of the main flue gas pipeline 31 and is used for centrally treating the thermally runaway flue gas buffered by the buffer device 2 of multiple energy storage devices 1. This centralized treatment can be direct emission treatment or adsorption treatment, etc., to avoid affecting the battery modules in the energy storage device 1.

[0095] Multiple energy storage devices 1 and the flue gas treatment device are arranged according to the on-site environment. Multiple energy storage devices 1 can be linearly arranged in one row or two rows, and the flue gas treatment device is arranged at the end; or, multiple energy storage devices 1 are arranged radially, and the flue gas treatment device is arranged at the center.

[0096] The above settings enable multiple energy storage devices 1 to share one flue gas treatment device. Compared with the prior art solution of separately setting flue gas treatment for each energy storage device 1, it can not only improve the safety of the energy storage device 1 during use, but also reduce the number of flue gas treatment devices, significantly reducing the manufacturing cost of the entire energy storage system. Secondly, the flue gas treatment device is separately arranged from the energy storage device 1, which is convenient for arranging and installing each component in the energy storage device 1, improving the space utilization rate inside the energy storage box 12, facilitating the integration of the energy storage device 1, and thus increasing the capacity of the energy storage device 1.

[0097] In addition, the above-mentioned flue gas treatment device can also be arranged in an empty energy storage box 12. The energy storage box 12 can provide safety protection for the flue gas treatment device, increasing its service life. At the same time, this setting makes the entire energy storage system convenient for standardization and modularization, facilitating on-site management and maintenance, and also having aesthetic properties.

[0098] Such as Figure 10 and Figure 11As shown in the figure, the flue gas treatment device in this embodiment includes a liquid treatment device 4, which is connected to the outlet of the main flue gas pipeline 31. The liquid treatment device 4 mainly includes M liquid treatment tanks 41, where M is an integer greater than or equal to 2, and the liquid treatment tanks 41 are filled with a liquid treatment medium. The number of the liquid treatment tanks 41 can be set according to the number and requirements of the battery modules 11 in each energy storage device 1. If there are multiple liquid treatment tanks 41, the multiple liquid treatment tanks 41 can be connected in series through connecting pipelines. The shape of the liquid treatment tank 41 is not limited and can be a rectangular tank, a circular tank, an oval tank, etc. Preferably, a circular tank is used, and the circular tank has good pressure-bearing performance.

[0099] As Figure 12 shown in the figure, a flue gas inlet and a flue gas outlet are provided on the liquid treatment tank 41. The flue gas inlet is used to input the thermal runaway flue gas into the liquid treatment tank 41, and the flue gas outlet is used to discharge the treated thermal runaway flue gas. When specifically setting the flue gas inlet, it can be set at the top of the liquid treatment tank 41 or at the bottom of the liquid treatment tank 41. For the convenience of connecting each liquid treatment tank 41, it is preferred to set both the flue gas inlet and the flue gas outlet at the top of the liquid treatment tank 41. At this time, each liquid treatment tank 41 only needs to be connected at the top, which improves the connectability of the entire liquid treatment device 4 and the compactness of the pipeline layout. In addition, the above-mentioned connecting pipeline can adopt a metal bellows. After connecting with the metal bellows, each liquid treatment tank 41 can be arranged according to the requirements of the installation space, meeting various installation requirements and saving installation space.

[0100] As Figure 12 shown in the figure, after the flue gas inlet is set at the top of the liquid treatment tank 41, in order to make the thermal runaway flue gas fully contact with the liquid treatment medium in the liquid treatment tank 41, a drainage pipe 42 is connected to the flue gas inlet, and at least part of the drainage pipe 42 can be immersed in the liquid treatment medium. Preferably, the drainage pipe 42 preferably extends to the bottom of the liquid treatment tank 41 and can be completely immersed in the liquid treatment medium. When the thermal runaway flue gas passes through the liquid treatment tank 41, it fully contacts the liquid treatment medium in the liquid treatment tank 41, and the liquid treatment medium conducts a relatively sufficient treatment on the thermal runaway flue gas, improving the treatment effect of the liquid treatment medium.

[0101] As Figure 12As shown in the figure, a flow splitting part 44 is provided at one end of the above-mentioned drainage pipe 42 immersed in the liquid treatment medium. The flow splitting part 44 disperses and splits the thermal runaway flue gas and then reacts with the liquid treatment medium in the liquid treatment tank 41, so that the thermal runaway flue gas enters in a large flow and exits in a small flow, which is conducive to the dispersion of the thermal runaway flue gas, makes the thermal runaway flue gas fully contact and react with the liquid treatment medium, and improves the treatment effect of the liquid treatment medium. The flow splitting part 44 can be a copper foam column. During specific installation, it is fixed to the port of the drainage pipe 42 immersed in the liquid treatment medium. Copper foam is a structure with a large number of three-dimensional porous structures in the copper matrix, which has a dispersion and buffering effect on fluids. When in use, it is processed into a columnar structure, and the thermal runaway flue gas passing through the drainage pipe 42 flows out from the copper foam column and then flows out through the side wall or bottom of the copper foam column to achieve the dispersion and buffering effect on the thermal runaway flue gas, so that the split thermal runaway flue gas fully contacts the liquid treatment medium.

[0102] As Figure 12 shown, in order to further make the thermal runaway flue gas fully react with the liquid treatment medium, a spiral baffle 45 is provided on the above-mentioned drainage pipe 42, or multiple baffle plates are provided on the drainage pipe 42. When the thermal runaway flue gas passes through the liquid treatment tank 41, the spiral baffle 45 or multiple baffle plates increase the travel of the thermal runaway flue gas, making the thermal runaway flue gas more fully contact the liquid treatment medium. The thermal runaway flue gas enters from the flue gas inlet of the liquid treatment tank 41, then enters the bottom of the liquid treatment medium through the drainage pipe 42, and then is dispersed by the copper foam column. During the process of rising from the bottom, the spiral baffle 45 or multiple baffle plates will make the thermal runaway flue gas fully contact the liquid treatment medium in the liquid treatment tank 41, so as to perform corresponding treatment. During specific connection, the spiral baffle 45 can be fixed on the drainage pipe 42. The baffle plate is a semi-circular baffle plate, and multiple baffle plates are arranged in sequence from bottom to top, respectively fixed on the drainage pipe 42, and adjacent baffle plates are installed in a staggered manner.

[0103] Before the above-mentioned liquid treatment tank 41 is used, a corresponding airtight pressure test for leak detection is generally required to ensure the sealing performance and reliability of the liquid treatment tank 41 during subsequent use. When the liquid treatment tank 41 is subjected to the pressure test for leak detection, generally, the empty liquid treatment tank 41 is subjected to the first pressure test for leak detection. After the first pressure test for leak detection is completed, the liquid treatment medium is filled into the liquid treatment tank 41, and then multiple liquid treatment tanks 41 are connected through connecting pipelines. After multiple liquid treatment tanks 41 are connected, a second pressure test for leak detection needs to be carried out on the connecting pipelines between the liquid treatment tanks 41. The two pressure tests for leak detection result in a low detection efficiency of the liquid treatment tank 41, and further reduce the assembly efficiency of the liquid treatment device 4.

[0104] As Figure 12As shown, in order to facilitate the injection of the liquid treatment medium and the pressure test for leakage detection of the liquid treatment tank 41, a three-way valve 43 is provided on the above-mentioned flue gas outlet. The three-way valve 43 can specifically be a three-way ball valve or the like. This three-way valve 43 can fill the liquid treatment medium after the pressure test for leakage detection of all the liquid treatment tanks 41 is completed. Specifically in the connection, the first port of the three-way valve 43 is connected to the flue gas outlet, the second port is used to discharge the thermal runaway flue gas, and the third port is used to inject the liquid treatment medium.

[0105] In other embodiments, after the above-mentioned liquid treatment tank 41 is provided with a flue gas inlet and a flue gas outlet, a liquid injection port can also be separately provided. A liquid injection valve is provided on the liquid injection port. The liquid injection valve is closed during the corresponding airtightness pressure test for leakage detection of each liquid treatment tank 41 and is opened during liquid injection.

[0106] The liquid treatment tanks 41 of the above-mentioned liquid treatment device 4 can all be filled with the liquid treatment medium. Specifically during filling, the liquid treatment medium is filled to about 2 / 3 of the inner cavity of the liquid treatment tank 41 to prevent the liquid treatment medium in the previous liquid treatment tank 41 from being squeezed into the next liquid treatment tank 41, resulting in poor treatment effects.

[0107] During actual use, the pressure of the thermal runaway flue gas during the initial explosion venting of the battery module 11 is too high, and the liquid treatment medium in the last liquid treatment tank 41 may be squeezed out of the liquid treatment tank 41 by the thermal runaway flue gas. Based on this, the last one or more liquid treatment tanks 41 can be set as empty tanks. For example, the liquid treatment device 4 includes 9 liquid treatment tanks 41. Among them, the first to the eighth liquid treatment tanks 41 are filled with 2 / 3 of the liquid treatment medium, and the ninth liquid treatment tank 41 is an empty tank. When the pressure of the thermal runaway flue gas discharged from the battery module 11 is too high, the empty tank can collect the liquid treatment medium squeezed out by the high-pressure thermal runaway flue gas, prevent the liquid treatment medium from being squeezed out of the liquid treatment tank 41 and causing harm, and improve the safety during the use of the liquid treatment device 4.

[0108] The liquid treatment medium filled in the above-mentioned liquid treatment tank 41 can specifically adopt the following substances:

[0109] First, the liquid treatment medium can be an organic solvent. According to the principle of similar solubility, the organic solvent can fully treat the electrolyte carried in the thermal runaway flue gas and can also prevent the vaporized electrolyte from continuing to decompose. This organic solvent is specifically an ester solvent, an alcohol solvent or an aldehyde solvent. The ester solvent can specifically be a diethyl phthalate solvent, a methyl salicylate solvent, an ethyl acetate solvent or a butyl acetate solvent, etc. The alcohol solvent can specifically be a benzyl alcohol solvent, an isoamyl alcohol solvent, an isobutyl alcohol solvent, an isopropyl alcohol solvent, an isooctyl alcohol solvent, a n-propyl alcohol solvent or a cyclohexanol solvent, etc. The aldehyde solvent is a benzaldehyde solvent, heptaldehyde, phenyl propionaldehyde or methyl nonyl acetaldehyde, etc.

[0110] Second, the liquid treatment medium is an alkaline solution, which can specifically be an aqueous sodium hydroxide solution, an aqueous potassium hydroxide solution, an aqueous barium hydroxide solution, etc. The alkaline solution can react with the carbonate substances in the electrolyte to prevent the continuously vaporized electrolyte from generating harmful gases, and perform a certain treatment on the thermal runaway flue gas at the source. At the same time, the alkaline solution can cool the thermal runaway flue gas and fully dissolve the electrolyte vapor in the thermal runaway flue gas in the alkaline solution. In addition, the alkaline solution has a good treatment effect on acidic substances such as CO2, POF3, and HF, and can effectively treat the thermal runaway flue gas.

[0111] Among the above two liquid treatment media, the alkaline solution not only treats the electrolyte in the thermal runaway flue gas to prevent the vaporized electrolyte from continuing the decomposition reaction, but also treats some of the reaction gases. After being treated by the alkaline solution of this concentration, the gas volume of the thermal runaway flue gas is greatly reduced. Therefore, compared with organic solvents, the alkaline solution has a better treatment effect.

[0112] For the alkaline solution, generally, the higher the concentration, the better the treatment effect on the thermal runaway flue gas. However, the applicant found that the treatment effect of a low-concentration alkaline solution is better than that of a high-concentration alkaline solution. Especially for the alkaline solution with a concentration of 0.05 - 0.5 mol / L, when the thermal runaway flue gas passes through the alkaline solution of this concentration, the collected gas volume is the smallest, and its treatment effect is better than that of the alkaline solution with a concentration above 0.5 mol / L. Therefore, when using an alkaline solution to treat the thermal runaway flue gas, overcoming the prejudice of the prior art, a low-concentration alkaline solution is used to treat the thermal runaway flue gas, enabling the alkaline solution to effectively treat the thermal runaway flue gas.

[0113] When the thermal runaway flue gas is transported into the NaOH solution, the NaOH solution reacts with the electrolyte, acidic substances such as CO2, POF3, and HF in the thermal runaway flue gas respectively. For example, the ester in the electrolyte reacts with the NaOH solution: CHOOCR + NaOH = RCOONa + CHOH; CO2 reacts with the NaOH solution: 2NaOH + CO2 = Na2CO3 + H2O; subsequently, CO2 will also react: Na2CO3 + CO2 + H2O = 2NaHCO3; POF3 reacts with the NaOH solution: POF3 + 2NaOH = NaPF2O2 + NaF + H2O; HF reacts with the NaOH solution: NaOH + HF = NaF + H2O. Through the above reactions, the volume of the thermal runaway flue gas is greatly reduced.

[0114] Taking the NaOH solution as an example of the alkaline solution, multiple thermal runaway tests were carried out. It was found that when the thermal runaway flue gas of a fully charged 32650 battery was not treated at all, the volume of the collected gas was 4L. When the thermal runaway flue gas of a fully charged 32650 battery passed through a NaOH solution with a concentration above 0.5 mol / L, the collected gas was generally more than 2L, and the treatment effect was not ideal. When the thermal runaway flue gas of a fully charged 32650 battery passed through a NaOH solution with a concentration of 0.05 - 0.5 mol / L, the gas volume was smaller, all below 2L. After treatment with a NaOH solution with a concentration of 0.1 - 0.2 mol / L, the effect was significant. After treatment with a 0.1 mol / L NaOH solution, the volume of the collected gas was the smallest, only about 1L, and the effect was the best. Therefore, a NaOH solution with a concentration of 0.05 - 0.5 mol / L has a good treatment effect on the thermal runaway flue gas after battery thermal runaway.

[0115] The above-mentioned large number of battery thermal runaway tests found that after horizontally comparing the treatment effects of water and NaOH solutions with different concentrations on thermal runaway flue gas, it was found that the volume of the gas collected after the thermal runaway flue gas was treated with a NaOH solution with a concentration of 0.05 - 0.5 mol / L was the smallest. After treatment with a NaOH solution with a concentration of 0.1 - 0.2 mol / L, the effect was significant. After treatment with a 0.1 mol / L NaOH solution, the effect was the best.

[0116] Example 4

[0117] The energy storage system provided in this example is similar to the energy storage system in Example 3. The difference is that the flue gas treatment device in this example includes a liquid treatment device 4 and an ignition device 6 arranged in sequence. As can be seen from Example 3, an alkaline solution with a certain concentration can effectively treat thermal runaway flue gas, making the volume of the treated thermal runaway flue gas decrease significantly. On this basis, an ignition device 6 is connected to the rear end of the liquid treatment device 4, and the ignition device 6 ignites the gas treated by the liquid treatment device 4.

[0118] As Figure 13 shown, the ignition device 6 is arranged at the rear end of the liquid treatment device 4 to controllably ignite the thermal runaway flue gas treated by the liquid treatment device 4. The above-mentioned ignition device 6 can adopt the structures disclosed in Chinese patents CN220324645U, CN219453979U, CN218523576U, CN218498146U, CN218414927U, etc.

[0119] In some embodiments, the flue gas treatment device may also only include the ignition device 6, and the ignition device 6 is directly connected to the flue gas main pipeline 31 to separately ignite the thermal runaway flue gas buffered by the buffer device 2 of each energy storage device 1.

[0120] AsFigure 13 As shown, the above ignition device 6 includes a flue gas pipeline 61 and at least one set of ignition components. The flue gas pipeline 61 is connected to the flue gas outlet of the Mth liquid treatment tank 41 in the liquid treatment device 4. The ignition components are connected to the flue gas pipeline 61. Among them, the number of ignition components can be set according to requirements, and can be set to multiple groups such as 1 group, 2 groups, 3 groups or 4 groups. When set to multiple groups, it can not only fully ignite the thermal runaway flue gas to ensure reliable ignition, but also avoid potential safety hazards caused by the inability to reliably ignite the thermal runaway flue gas when a single ignition component fails or malfunctions.

[0121] As Figure 13 shown, each ignition component includes an exhaust pipe 62 and an igniter 63 arranged at the outlet of the exhaust pipe 62. The exhaust pipe 62 is connected to the flue gas pipeline 61 (when there is 1 ignition component, the exhaust pipe 62 and the flue gas pipeline 61 share a pipeline; when there are multiple ignition components, the inlets of the exhaust pipes 62 of multiple ignition components are all communicated with the flue gas pipeline 61). The igniter 63 is turned on when any battery module 11 has a thermal runaway. Subsequently, the thermal runaway flue gas treated by the liquid treatment device 4 is transported by the flue gas pipeline 61 into the exhaust pipe 62, and the igniter 63 ignites the thermal runaway flue gas discharged from the exhaust pipe 62. The ignition of the igniter 63 can be turned on by a trigger 64 or by a BMS (Battery Management System). When turned on by the trigger 64, the trigger 64 can be sensors of different structures, which can be arranged in the exhaust pipe 62 or on the flue gas pipeline 61 to detect parameters such as temperature, pressure or gas volume fraction in real time, and can send a signal to start the igniter 63 when exceeding the set threshold. Specifically, the above trigger 64 can be at least one of a pressure sensor, a gas sensor, a temperature sensor or a pneumatic switch. When starting through the trigger 64, a flame arrester 65 can also be arranged on the exhaust pipe 62. The flame arrester 65 is preferably a pipeline flame arrester 65, which is used to prevent the flame from transmitting downward through the exhaust pipe 62 and damaging devices such as the trigger 64. When turned on by the BMS, the BMS monitors the voltage, current and temperature of each battery module 11 in the energy storage device 1 in real time. When any battery module 11 has a thermal runaway and the voltage, voltage and temperature exceed the threshold, the igniter 63 is started.

[0122] The structure of the above igniter 63 can be various. For example, an existing arc igniter or a resistance wire igniter can be specifically adopted. The arc igniter can specifically adopt a pulse igniter. The power supply mode of the igniter 63 can adopt dry batteries or alternating current according to the on-site environment.

[0123] Example 5

[0124] As Figure 14As shown, the energy storage system provided in this embodiment is similar to the energy storage system in Embodiment 1. Different from Embodiment 3, the flue gas treatment device in this embodiment includes a liquid treatment device 4 and a solid treatment device 7 arranged in sequence. From the test results in Embodiment 3, it can be seen that an alkali solution with a certain concentration can effectively treat the thermal runaway flue gas, significantly reducing the volume of the treated thermal runaway flue gas. On this basis, the solid treatment device 7 can be used to treat the remaining gas, making the treated thermal runaway flue gas completely non-combustible.

[0125] The specific structure of the liquid treatment device 4 has been described in detail in Embodiment 3 and will not be elaborated in this embodiment. The solid treatment device 7 is arranged at the rear end of the liquid treatment device 4 and is used to treat the thermal runaway flue gas treated by the liquid treatment device 4. The solid treatment device 7 includes at least one solid treatment tank 71. The number of solid treatment tanks 71 can be set according to the number and requirements of the energy storage devices 1 in the energy storage system. If there are multiple solid treatment tanks 71, the multiple solid treatment tanks 71 can be arranged in series. At this time, the flue gas inlet of the first solid treatment tank 71 is connected to the flue gas outlet of the last liquid treatment tank 41 in the liquid treatment device 4. The specific structure of the solid treatment tank 71 is similar to that of the liquid treatment tank 41, and its interior is filled with a solid adsorption medium for treating the thermal runaway flue gas treated by the liquid treatment tank 41.

[0126] The solid adsorption medium in the above-mentioned solid treatment tank 71 can specifically be activated carbon, graphene, carbon nanotubes, graphite, alumina, montmorillonite, silicate, phosphate, or porous glass, etc., for treating the residual gas treated by the liquid treatment tank 41. For example, it can adsorb excess H2, CO, methane, ethylene, etc. Preferably, the above-mentioned solid adsorption medium is selected as activated carbon with relatively low cost and relatively excellent treatment effect. Generally, activated carbon with a higher iodine value or modified activated carbon is selected. This type of activated carbon is easy to adsorb small molecular weight gases in the thermal runaway flue gas. For example, it is easy to react with hydrogen, methane, etc.

[0127] Through test data, it is found that the effect of treating the thermal runaway flue gas of a battery thermal runaway with NaOH solution and activated carbon (activated carbon in No. 1 gas mask P-B-3) is very good. After multiple tests, it is found that the thermal runaway flue gas after the thermal runaway of a fully charged 32650 battery first passes through 1500 mL of 0.1 mol / L NaOH solution for treatment, and then passes through 270 g of activated carbon for adsorption. The volume of the collected gas is between 0.3 and 0.5 L, and the collected gas is non-combustible.

[0128] Embodiment 6

[0129] The energy storage system provided in this embodiment is similar to the energy storage system in Embodiment 3. Different from Embodiment 3, the flue gas treatment device in this embodiment includes a solid treatment device 7 and an ignition device 6 arranged in sequence.

[0130] The above-mentioned solid treatment device 7 includes at least one solid treatment tank 71, and the number of solid treatment tanks 71 can be set according to the number and requirements of the energy storage devices 1 in the energy storage system. The ignition device 6 is arranged at the rear end of the solid treatment device 7 and is connected to the flue gas outlet of the last solid treatment tank 71 to perform a controllable ignition treatment on the thermal runaway flue gas treated by the solid treatment device 7. For the specific structures of the solid treatment device 7 and the ignition device 6, please refer to Embodiment 5 and Embodiment 4, and no detailed description will be given in this embodiment.

[0131] Embodiment 7

[0132] As Figure 15 shown, the energy storage system provided in this embodiment is similar to the energy storage system in Embodiment 3. The difference is that the thermal runaway flue gas treatment device in this embodiment includes a flue gas cooling device 5 and a solid treatment device 7.

[0133] As Figure 15 shown, the flue gas cooling device 5 is used to cool the thermal runaway flue gas. The flue gas cooling device 5 includes at least one cooling treatment tank 51. Each cooling treatment tank 51 is provided with a flue gas inlet and a flue gas outlet. If there are multiple cooling treatment tanks 51, the multiple cooling treatment tanks 51 can be arranged in series. At this time, the flue gas inlet of the first cooling treatment tank 51 is connected to the main flue gas pipeline 31. The inside of the cooling treatment tank 51 is filled with a cooling medium for cooling the thermal runaway flue gas. The cooling medium can specifically be ceramic balls, silica, alumina, zirconia, titanium oxide, graphite rods, porous ceramics, etc. When the thermal runaway flue gas passes through the cooling treatment tank 51, the electrolyte carried in the thermal runaway flue gas is cooled to a liquid state after passing through the cooling medium and is collected in the cooling treatment tank 51, thereby reducing the concentration of combustibles in the thermal runaway flue gas. At the same time, the cooling treatment tank 51 also cools the gas in the thermal runaway flue gas and can reduce the temperature of the thermal runaway flue gas.

[0134] The thermal runaway flue gas cooled by the above-mentioned flue gas cooling device 5 enters the solid treatment device 7. The flue gas outlet of the last cooling treatment tank 51 is connected to the flue gas inlet of the first solid treatment tank 71 in the solid treatment device 7. The solid treatment device 7 adsorbs the thermal runaway flue gas so that the discharged thermal runaway flue gas is not harmful. For the specific structure of the solid treatment device 7, please refer to Embodiment 5, and no detailed description will be given in this embodiment.

Claims

1. An energy storage system, comprising at least two energy storage devices, characterized in that: Each energy storage device includes an energy storage box, a flue gas manifold, a buffer device and at least one battery module; The battery module is arranged in the energy storage box; The thermal runaway smoke generated by each battery module is transported to the buffer device through the smoke manifold; The buffer device comprises at least one buffer tank for buffering the thermal runaway flue gas.

2. The energy storage system according to claim 1, characterized in that: The battery module includes a plurality of single cells, and the inner cavity of each single cell is connected with at least one shared chamber.

3. The energy storage system according to claim 2, characterized in that: The battery module includes an outer shell and a plurality of single cells arranged in the outer shell in the same direction; the outer shell is provided with a shared chamber, the inner cavity of the shared chamber is connected with the inner cavities of all the single cells; avoidance holes are provided on the top plate of the outer shell corresponding to the polarity terminals of each single cell; the polarity terminals of each single cell extend out of the avoidance holes, and the top plate area of ​​the outer shell corresponding to the avoidance holes is fixedly sealed with the shell of the single cell.

4. The energy storage system according to claim 3, characterized in that: The shared chamber includes at least one of an electrolyte shared chamber and a gas shared chamber; the electrolyte shared chamber is communicated with the electrolyte area of ​​each single battery, and the gas shared chamber is communicated with the gas area of ​​each single battery.

5. The energy storage system according to claim 3, characterized in that: The shared chamber includes an electrolyte shared chamber and a gas shared chamber. The electrolyte shared chamber is connected to the electrolyte area of ​​each single cell. The gas shared chamber is a gas channel located between the top plate of the outer shell and each single cell. The gas channel covers the explosion venting part of each single cell. When the explosion venting part of any single cell is broken by the thermal runaway smoke in the inner cavity, the gas area and gas channel of the single cell are connected.

6. The energy storage system according to any one of claims 2 to 5, characterized in that: The flue gas manifold includes a primary manifold and a secondary manifold. The primary manifold is connected to the battery modules arranged in the same row, and the secondary manifold is connected to each primary manifold to centrally transport the thermal runaway flue gas in each primary manifold to the buffer tank.

7. The energy storage system according to claim 6, characterized in that: The battery module is provided with an explosion relief pipe assembly connected to the shared chamber; the explosion relief pipe assembly includes a first explosion relief component and a second explosion relief component; the first explosion relief component includes a first hollow tube connected to the shell, and an explosion relief membrane is provided in the first hollow tube; The second explosion relief component is a three-way pipe, a first interface of which is sealed and connected to the first explosion relief component, and the second interface and the third interface of the second explosion relief components of two adjacent battery modules are connected through a flexible pipe section to form a primary collector.

8. The energy storage system according to claim 7, characterized in that: The first explosion relief component also includes a second hollow pipe connected to the first hollow pipe; the second hollow pipe is made of insulating material, the second explosion relief component is a flexible tee, and the flexible joint of the second explosion relief component is threadedly connected to the second hollow pipe.

9. The energy storage system according to any one of claims 1 to 5, characterized in that: The buffer tank is provided with a smoke inlet and a smoke outlet communicated with its inner cavity. The smoke inlet and the smoke outlet of the buffer tank are both arranged at the top of the buffer tank. A drain valve is arranged at the bottom of the buffer tank. The buffer device is arranged in the energy storage box.

10. The energy storage system according to any one of claims 1 to 5, characterized in that: It also includes a smoke conveying pipeline; the smoke conveying pipeline includes a smoke main pipeline and multiple smoke branch pipelines, each smoke branch pipeline is used to be connected to the buffer device of each energy storage equipment, and is used to convey the thermal runaway smoke after buffering treatment by the buffer device of each energy storage equipment to the smoke main pipeline; the smoke main pipeline centrally discharges the thermal runaway smoke after buffering treatment by the buffer devices of multiple energy storage equipment.

11. The energy storage system according to claim 10, characterized in that: A flue gas treatment device is provided at the outlet of the flue gas main line, and the flue gas treatment device includes at least one of a liquid treatment device, a solid treatment device, a flue gas cooling device and an ignition device, and is used for centrally treating the thermal runaway flue gas after buffering treatment by buffer devices of multiple energy storage devices.

12. The energy storage system according to claim 11, characterized in that: The liquid treatment device includes M liquid treatment tanks, each of which is provided with a flue gas inlet and a flue gas outlet, the first liquid treatment tank to the M-1th liquid treatment tank are filled with liquid treatment medium, the Mth liquid treatment tank is an empty tank, wherein M is an integer greater than or equal to 2, the liquid treatment medium is an alkaline solution, and the alkaline solution is a 0.05-0.5 mol / L NaOH solution.

13. The energy storage system according to claim 12, characterized in that: The flue gas treatment device includes a liquid treatment device and an ignition device; the ignition device is connected to the flue gas outlet of the Mth liquid treatment tank and is used to ignite the thermal runaway flue gas treated by the liquid treatment device.

14. The energy storage system according to claim 10, characterized in that: The smoke branch pipe is provided with a one-way valve for allowing the thermal runaway smoke to flow in one direction, and the smoke branch pipe is provided with a suction device for sucking the thermal runaway smoke.

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