Energy storage equipment

Abstract

The utility model provides energy storage equipment which mainly solves the problem that potential safety hazards exist after a battery module is thermally runaway and smoke is exhausted. The energy storage equipment comprises a flue gas treatment system and at least one battery module, the battery module comprises a shell and a plurality of single batteries arranged in the shell along the same direction; a shared chamber is arranged in the shell, and the inner cavity of the shared chamber is communicated with the inner cavities of all the single batteries; the flue gas treatment system comprises a flue gas collecting pipe and a flue gas treatment unit, the flue gas collecting pipe is used for conveying thermal runaway flue gas generated by each battery module into the flue gas treatment unit, and the flue gas treatment unit is used for treating the thermal runaway flue gas so as to reduce potential safety hazards generated after the thermal runaway flue gas is discharged.

Description

Technical Field

[0001] The utility model belongs to the field of energy storage batteries, and particularly relates to an energy storage device. 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 devices, the safe use of lithium-ion batteries has also attracted attention. Since the battery modules in the energy storage device are highly concentrated, under the influence of factors such as overcharging, over-discharging, overheating, and mechanical collision of the battery, it is easy to cause the breakdown of the battery separator and internal short circuit, resulting in thermal runaway and generating thermal runaway flue gas. After the above-mentioned thermal runaway flue gas is discharged, it is easy to accumulate and catch fire, and in severe cases, it will cause an explosion, posing a safety hazard. Summary of the Invention

[0004] In order to solve the problem of potential safety hazards after the existing thermal runaway flue gas is discharged, the utility model provides an energy storage device.

[0005] In order to solve the above problems, the technical solution provided by the utility model is as follows:

[0006] An energy storage device includes a flue gas treatment system and at least one battery module; 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 is communicated with the inner cavities of all single cells; avoidance holes are opened 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 single cell housing; the flue gas treatment system includes a flue gas confluence pipe and a flue gas treatment unit, the flue gas confluence pipe is used to transport the thermal runaway flue gas generated by each battery module to the flue gas treatment unit, and the flue gas treatment unit is used to treat the thermal runaway flue gas.

[0007] Further, the shared chamber is an electrolyte shared chamber, the electrolyte shared chamber is communicated with the electrolyte areas of each single cell, a pressure relief pipe assembly communicated with the electrolyte shared chamber is arranged on the housing, and the pressure relief pipe assembly is connected with the flue gas confluence pipe.

[0008] Further, the shared chamber is a gas shared chamber, the gas shared chamber is communicated with the gas areas of each single cell, a pressure relief pipe assembly communicated with the gas shared chamber is arranged on the housing, and the flue gas confluence pipe is connected with the pressure relief pipe assembly.

[0009] Furthermore, the shared chamber includes an electrolyte shared chamber and a gas shared chamber. The electrolyte shared chamber is communicated with the electrolyte regions of the individual cells, and the gas shared chamber is communicated with the gas regions of the individual cells. An explosion vent pipe assembly is provided on the outer shell. At least one of the gas shared chamber and the electrolyte shared chamber is communicated with the explosion vent pipe assembly, and the flue gas manifold is connected to the explosion vent pipe assembly.

[0010] Furthermore, the shared chamber includes an electrolyte shared chamber and a gas shared chamber. The electrolyte shared chamber is communicated with the electrolyte regions of the individual cells, and the gas shared chamber is a gas passage located between the top plate of the outer shell and the individual cells. This gas passage covers the explosion vent parts of the individual cells. When the explosion vent part of any individual cell is broken through by the hot runaway flue gas in the inner cavity, the gas region of this individual cell is communicated with the gas passage.

[0011] Furthermore, the flue gas treatment unit includes at least one of a liquid treatment device, a solid treatment device, a flue gas cooling device, and an ignition device; the liquid treatment device is mainly used for treating the electrolyte and gas in the hot runaway flue gas; the flue gas cooling device is mainly used for cooling the hot runaway; the solid treatment device is mainly used for adsorbing the gas in the hot runaway flue gas; the ignition device is used for igniting the hot runaway flue gas.

[0012] Furthermore, 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 all 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.

[0013] Furthermore, the flue gas treatment unit 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 hot runaway flue gas treated by the liquid treatment device.

[0014] Furthermore, the liquid treatment medium is an alkali solution, and the alkali solution is a 0.05 - 0.5 mol / L NaOH solution.

[0015] Furthermore, the flue gas treatment system further includes a buffer device. The buffer device includes at least one buffer tank. The buffer tank is provided with a flue gas inlet and a flue gas outlet communicated with its inner cavity. The buffer device is arranged between the flue gas manifold and the flue gas treatment unit and is used for buffering the hot runaway flue gas.

[0016] Further, the flue gas treatment system further includes a safety device, which includes a safety pipeline and a safety discharge part; the inlet of each safety pipeline is communicated with the flue gas confluence pipe, and the outlet of the safety pipeline is communicated with the external environment; the safety discharge part is arranged on the safety pipeline, and its opening pressure is less than the opening pressure of the explosion relief part of the battery module.

[0017] Further, the flue gas confluence pipe includes a primary confluence pipe and a secondary confluence pipe. The primary confluence pipe is connected to the battery modules arranged in the same row, and the secondary confluence pipe is connected to each primary confluence pipe to centrally transport the thermal runaway in each primary confluence pipe to the flue gas treatment unit.

[0018] Further, 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 pipe fitting connected to the outer shell, and an explosion relief membrane is arranged inside the first hollow pipe fitting; the second explosion relief component is a tee pipe, its first interface is hermetically connected to the first explosion relief component, and the second interfaces and third interfaces of the second explosion relief components of adjacent two battery modules are connected through flexible pipe segments to form a primary confluence pipe.

[0019] Further, the first explosion relief component 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 explosion relief component is a union tee pipe, and the union joint of the second explosion relief component is threadedly connected to the second hollow pipe fitting.

[0020] Compared with the prior art, the technical solution of the present utility model has the following advantages:

[0021] 1. In the energy storage device of the present utility model, the battery module places multiple single cells in one outer shell with a shared chamber, and utilizes the fact that the shared chamber communicates with the inner cavities of the single cells located inside the outer shell, reducing the differences between the single cells, improving the consistency between the single cells to a certain extent, and thus improving the cycle life of the battery module to a certain extent. At the same time, a flue gas treatment system is also provided in the energy storage device, and this flue gas treatment system treats the thermal runaway flue gas generated by the battery module to reduce the potential safety hazards after the thermal runaway flue gas is discharged.

[0022] 2. In the energy storage device 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 is a liquid channel located at the bottom plate of the outer shell, and the liquid channel is communicated with the electrolyte areas in the inner cavities of each single battery. By making the electrolyte shared chamber communicate with the electrolyte areas in the inner cavities of each single battery located in the outer shell, the electrolytes of each single battery are shared to ensure the consistency of each single battery, thereby improving the cycle life of the battery module to a certain extent. The gas shared chamber is a gas channel located at the top plate of the outer shell, and the gas channel is communicated with the gas areas in the inner cavities of each single battery. By making the gas shared chamber communicate with the gas areas in the inner cavities of each single battery located in the outer shell, the gas balance of each single battery is achieved, improving the consistency between each single battery to a certain extent, and thereby improving the cycle life of the battery module to a certain extent.

[0023] 3. In the energy storage device of the present utility model, the shared chamber includes an electrolyte shared chamber and a gas shared chamber; the electrolyte shared chamber is communicated with the electrolyte areas of each single battery, and the gas shared chamber is a gas channel located between the top plate of the outer shell and each single battery. This gas channel serves as a shared explosion relief channel. When the explosion relief part of any single battery is broken through by the internal cavity flue gas, the thermal runaway flue gas in the inner cavity of this single battery is discharged through the gas channel, improving the safety of the battery module.

[0024] 4. In the energy storage device of the present utility model, the flue gas treatment unit includes at least one of a liquid treatment device, a solid treatment device, a flue gas cooling device, and an ignition device; the flue gas treatment unit treats the thermal runaway flue gas generated by the energy storage device in various ways to avoid potential safety hazards caused by the discharge of the thermal runaway flue gas.

[0025] 5. In the energy storage device of the present utility model, since there is a certain amount of electrolyte in the above-mentioned battery module, when the battery module undergoes thermal runaway, the electrolyte is ejected with the thermal runaway flue gas and then passes through the liquid treatment device. The liquid treatment device effectively treats the electrolyte in the thermal runaway flue gas. 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 flue gas is too high, the empty tank can collect the liquid treatment medium extruded from the liquid treatment tank by the high-pressure thermal runaway flue gas, preventing the liquid treatment medium from being squeezed into the subsequent devices and affecting the devices at the back.

[0026] 6. In the energy storage device of the present utility model, the flue gas treatment unit includes a liquid treatment device and an ignition device. The ignition device performs a controllable ignition treatment on the thermal runaway flue gas treated by the liquid treatment device, and the thermal runaway flue gas after the ignition treatment can be directly discharged without potential hazards such as combustion and explosion.

[0027] 7. In the energy storage device of the present utility model, the liquid treatment medium is an alkali solution. This alkali 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 alkali 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 alkali solution is greatly reduced. Among them, the treatment effect of the thermal runaway flue gas with a NaOH solution of 0.05 - 0.5 mol / L is relatively prominent.

[0028] 8. In the energy storage device of the present utility model, a buffer tank is added at the front end of the flue gas treatment unit. The buffer tank not only buffers the thermal runaway flue gas, and the thermal runaway flue gas enters the flue gas treatment unit at a relatively stable flow rate, so that the thermal runaway flue gas is fully treated by the liquid treatment device. At the same time, this buffer tank can collect some of the electrolyte carried in the thermal runaway flue gas to reduce the usage amount of the subsequent liquid treatment device.

[0029] 9. A safety device is added to the energy storage device of the present utility model. When the pressure of the thermal runaway flue gas in the flue gas confluence pipe is too high, the safety device can discharge the thermal runaway flue gas through the safety device to avoid potential safety hazards caused by excessive pressure in the flue gas confluence pipe, and improve the safety during the treatment of the thermal runaway flue gas.

[0030] 10. In the energy storage device of the present utility model, the flue gas confluence pipe includes a primary confluence pipe and a secondary confluence pipe. The primary confluence pipe is connected to the battery modules arranged in the same row, and the secondary confluence pipe centrally conveys the thermal runaway flue gas in each primary confluence pipe to the flue gas treatment unit. The above flue gas confluence pipe converges the thermal runaway flue gas of all battery modules in the energy storage device. When a single battery in any battery module has a thermal runaway, its thermal runaway flue gas can be discharged through the flue gas confluence pipe, reducing the risk of thermal runaway diffusion.

[0031] 11. In the energy storage device of the present utility model, the explosion vent pipe assembly of the battery module is designed as a tee pipe section, and the tee pipe sections of adjacent battery modules are connected by a flexible pipe section to form a primary confluence pipe. Compared with the flue gas confluence pipe using an integral pipe structure, the installation accuracy requirements for the explosion vent pipe assemblies of each battery module are smaller. The installation deviation of the explosion vent pipe assembly can be compensated by the deformation of the flexible pipe section, reducing the installation difficulty of the flue gas confluence pipe.

[0032] Other advantages, objectives and features of the present utility model will be partially reflected by the following description, and partially will also be understood by those skilled in the art through the research and practice of the present utility model. Brief Description of the Drawings

[0033] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0034] Figure 1 Schematic diagram of the energy storage device in Embodiment 1;

[0035] Figure 2 Schematic structure of the battery module in Embodiment 1 Figure 1 ;

[0036] Figure 3 Schematic structure of the battery module in Embodiment 1 Figure 2 ;

[0037] Figure 4 Schematic connection diagram of each battery module and the flue gas manifold in Embodiment 1;

[0038] Figure 5 Partial explosion view of each battery module and the flue gas manifold in Embodiment 1;

[0039] Figure 6 Explosion of the explosion relief pipe assembly in Embodiment 1 Figure 1 ;

[0040] Figure 7 Explosion of the explosion relief pipe assembly in Embodiment 1 Figure 2 ;

[0041] Figure 8 Schematic structure diagram of the liquid treatment device in Embodiment 1;

[0042] Figure 9 Schematic structure diagram of the flue gas treatment unit in Embodiment 2;

[0043] Figure 10 Schematic structure diagram of the flue gas treatment unit in Embodiment 3;

[0044] Figure 11 Schematic structure diagram of the flue gas treatment unit in Embodiment 4;

[0045] Figure 12 Schematic diagram of the energy storage device in Embodiment 4;

[0046] Figure 13 Schematic diagram of the energy storage device in Embodiment 5.

[0047] Reference Numerals: 1 - battery module, 2 - flue gas manifold, 3 - liquid treatment device, 4 - explosion relief pipe assembly, 5 - solid treatment device, 6 - ignition device, 7 - buffer device, 8 - safety device, 11 - housing, 12 - single cell, 13 - polar terminal, 14 - insulation shield, 111 - electrolyte sharing chamber, 112 - gas sharing chamber, 21 - primary manifold, 211 - flexible pipe section, 22 - secondary manifold, 31 - liquid treatment tank, 32 - flue gas inlet, 33 - flue gas outlet, 34 - drainage pipe, 35 - flow splitting section, 36 - three-way valve, 37 - spiral baffle, 38 - connecting pipeline, 41 - first explosion relief member, 411 - first hollow pipe fitting, 412 - second hollow pipe fitting; 42 - second explosion relief member; 51 - solid treatment tank, 61 - flue gas pipeline, 62 - exhaust pipe, 63 - igniter, 64 - trigger, 65 - flame arrester, 71 - buffer tank, 72 - flue gas inlet, 73 - flue gas outlet, 74 - drain valve, 81 - safety pipeline, 82 - safety discharge section, 821 - pressure measuring device, 822 - control valve. Detailed Embodiment

[0048] 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 in conjunction with the accompanying drawings of the specification. Obviously, the described embodiments are some, but not all, of the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the scope of protection of the present utility model.

[0049] In this specification, "in other embodiments" that appears in different places does not necessarily refer to the same embodiment, nor is it a separate 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 specifying 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.

[0050] 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.

[0051] Meanwhile, 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. It 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. Therefore, it should not be construed as a limitation to the present utility model.

[0052] Embodiment 1

[0053] As Figure 1 shown, the energy storage device provided in this embodiment includes at least one battery module 1, a flue gas manifold 2, and a flue gas treatment system; the number of battery modules 1 is set according to the requirements of the energy storage device, and multiple battery modules 1 are connected in series and parallel to meet the charging and discharging requirements. The flue gas treatment system includes a flue gas manifold and a flue gas treatment unit. The flue gas manifold 2 is used to convey the thermal runaway generated by the battery module 1 to the flue gas treatment unit; the flue gas treatment unit is used to treat the thermal runaway flue gas generated by each battery module 1. The structures of the battery module 1, the flue gas manifold 2, and the flue gas treatment unit will be described in detail below.

[0054] As Figure 2 shown, the battery module 1 in this embodiment includes a housing 11 and multiple single cells 12. The multiple single cells 12 are arranged in the same direction and placed inside the housing 11. The housing 11 is provided with a shared chamber, and the inner cavity of the shared chamber is communicated with the inner cavities of all the single cells 12. The single cells 12 in this embodiment are square shell batteries, and the number can be adjusted according to actual needs. The inner cavity of each single cell 12 includes an electrolyte area and a gas area.

[0055] As Figure 2 shown, after the multiple single cells 12 are arranged in the same direction and placed inside the housing 11, avoiding holes are provided on the top plate of the housing 11 corresponding to the polarity terminals 13 of each single cell 12. The polarity terminals 13 of each single cell 12 extend out of the corresponding avoiding holes to serve as the polarity terminals of the battery module 1 (the polarity terminals 13 of all the single cells 12 on one side serve as the positive polarity terminals of the battery module 1, and the polarity terminals 13 of all the single cells 12 on the other side serve as the negative polarity terminals of the battery module 1). The area of the top plate of the housing 11 corresponding to the avoiding holes is fixedly sealed with the shell of the single cell 12, so that the gap between the polarity terminal 13 and the avoiding hole is sealed.

[0056] It should be noted that the polarity terminal 13 of the single cell 12 here can be the pole column of the single cell 12. If it is necessary to avoid the pole column of the single cell 12 as the polarity terminal 13 from not being able to smoothly extend out of the avoiding hole, a pole column adapter can also be connected to the pole column of the single cell 12, and the overall structure formed by the cooperation of the pole column of the single cell 12 and the pole column adapter is used as the polarity terminal 13 of the single cell 12.

[0057] The shared chamber within the above-mentioned housing 11 may be an electrolyte shared chamber 111. The inner cavity of the electrolyte shared chamber 111 is in communication with the electrolyte regions in the inner cavities of all the single cells 12. Through the electrolyte shared chamber 111, each single cell 12 can be in a unified electrolyte environment, ensuring the uniformity of the electrolyte within each single cell 12 and enhancing the performance and charge-discharge cycle life of the battery module 1.

[0058] The above-mentioned shared chamber may be a gas shared chamber 112. The inner cavity of the gas shared chamber 112 is in communication with the gas regions in the inner cavities of all the single cells 12. Through the gas shared chamber 112, gas balance of each single cell 12 can be achieved, and it can also enhance the performance and charge-discharge cycle life of the battery module 1.

[0059] The above-mentioned shared chamber may be a gas-liquid shared chamber. The inner cavity of the gas-liquid shared chamber is in communication with both the electrolyte region and the gas region in the inner cavities of all the single cells 12. Through one gas-liquid shared chamber, each single cell 12 can be in a unified electrolyte environment and gas environment, enhancing the performance and charge-discharge cycle life of the battery module 1. There is a protrusion extending along the arrangement direction of the single cells 12 on the side wall of the housing, and a gas-liquid shared chamber is formed at the protrusion part. This gas-liquid shared chamber is in communication with both the electrolyte region and the gas region of each single cell.

[0060] The above-mentioned shared chamber may simultaneously include an electrolyte shared chamber 111 and a gas shared chamber 112. The inner cavity of the electrolyte shared chamber 111 is in communication with the electrolyte regions in the inner cavities of all the single cells 12, and the inner cavity of the gas shared chamber 112 is in communication with the gas regions in the inner cavities of all the single cells 12. The above-mentioned battery module 1 places multiple single cells 12 inside a housing 11 having a shared chamber, and utilizes the communication between the shared chamber and the inner cavities of each single cell 12 located inside the housing 11, enabling the sharing of electrolyte and gas of each single cell 12 to ensure the consistency of each single cell 12, that is, connecting the electrolyte and gas of each single cell 12, so that the electrolyte and gas of all single cells 12 are in the same system, reducing the differences between each single cell 12, and to a certain extent enhancing the consistency between each single cell 12, thereby to a certain extent enhancing the cycle life of the battery module 1.

[0061] The above-mentioned shared chamber may simultaneously include an electrolyte shared chamber 111 and a gas shared chamber 112. The inner cavity of the electrolyte shared chamber 111 is in communication with the electrolyte regions in the inner cavities of all the single cells 12, and the gas shared chamber 112 is a gas passage located between the top plate of the housing and each single cell. This gas passage covers the explosion relief part of each single cell 12. When the explosion relief part of any single cell 12 is broken through by the hot runaway flue gas in the inner cavity, the gas region in the inner cavity of this single cell is in communication with the inner cavity of the gas chamber.

[0062] At this time, the housing 11 provided with the gas sharing chamber 112 and the electrolyte sharing chamber 111 may specifically adopt the following structures:

[0063] 1) The housing includes an outer cylinder, an upper cover, and a lower cover; both the top and bottom of the outer cylinder are open, the upper cover is hermetically fixed (welded) to the top of the outer cylinder, and an avoidance hole is provided on the upper cover through which the pole columns of each single battery can extend. The lower cover is hermetically fixed (welded) to the bottom of the outer cylinder. At the same time, a protrusion extending along the arrangement direction of the single batteries is provided on the upper cover, and a gas sharing chamber is formed at the protrusion part. A protrusion extending along the arrangement direction of the single batteries is provided on the lower cover, and an electrolyte sharing chamber is formed at the protrusion part;

[0064] 2) The housing includes a U-shaped housing, a first cover plate, a third cover plate, and a second cover plate; the first cover plate and the third cover plate respectively cover two opposite open ends of the U-shaped housing; the second cover plate covers the open end at the top of the U-shaped housing and is hermetically connected to the open end, and an avoidance hole is provided on the second cover plate through which the pole columns of each single battery can extend. At the same time, a protrusion extending along the arrangement direction of the single batteries is provided on the second cover plate, and a gas sharing chamber is formed at the protrusion part. An electrolyte sharing chamber is provided at the bottom of the U-shaped housing, and the electrolyte sharing chamber is a liquid passage provided between the bottom plate of the housing and each single battery;

[0065] 3) As Figure 2 shown, the housing 11 includes an outer cylinder, a front cover, and a rear cover; both the front and rear of the outer cylinder are open, the front cover is hermetically fixed (welded) to the front of the outer cylinder, and the rear cover is hermetically fixed (welded) to the rear of the outer cylinder, Figure 2 The rear cover is omitted in the figure. An avoidance hole through which the pole columns of each single battery 12 can extend is provided at the top of the outer cylinder. A protrusion extending along the arrangement direction of the single batteries 12 is provided at the top of the outer cylinder, and a gas sharing chamber 112 is formed at the protrusion part. An electrolyte sharing chamber 111 is provided at the bottom of the outer cylinder, and the electrolyte sharing chamber 111 is a liquid passage provided between the bottom plate of the outer cylinder and the bottoms of each single battery 12.

[0066] The above-mentioned housing is provided with a gas sharing chamber 112 at the top, and the gas sharing chamber 112 covers the gas ports at the tops of each single battery 1 in the battery module. Here, the gas port has the following two meanings:

[0067] 1) The gas port is a through hole directly opened on the upper cover plate of the single battery 12 and penetrating through the inner cavity of the single battery 12; at this time, the inner cavity of the gas sharing chamber 112 is communicated with the gas areas of the inner cavities of the respective single batteries 12 through this gas port. The gas sharing chamber 112 serves as the gas sharing chamber for each single battery 12. Based on the gas sharing chamber 112, the gas areas of the respective single batteries 12 can be communicated to achieve gas balance, enabling the gas sharing of each single battery 12 to ensure the consistency of each single battery 12, and improving the cycle life of the battery module to a certain extent; when any single battery 12 undergoes thermal runaway, the flue gas in the inner cavity of this single battery 1 enters the gas sharing chamber 112 and is discharged through the gas sharing chamber 112, improving the safety of this battery module.

[0068] 2) The gas port is a pressure relief port or explosion-proof port provided on the upper cover plate of the single battery 12, and a pressure relief part is provided at the pressure relief port or explosion-proof port. The pressure relief part is specifically a pressure relief membrane; at this time, the gas sharing chamber 112 is used as a pressure relief channel. When the pressure relief membrane at the gas port of any single battery 12 is broken by the flue gas in the inner cavity, the flue gas in the inner cavity of this single battery 12 is discharged through the gas sharing chamber 112, improving the safety of this battery module.

[0069] As Figure 3 shown, on the basis of the above structure, in this embodiment, an insulating protective cover 14 is further provided on the top of the battery module 1, thereby providing insulating protection for the polar terminals 13, avoiding potential safety hazards that may exist when the polar terminals 13 are exposed during the operation of the battery module 1, and also avoiding the problem that some foreign objects in the external environment fall into the position of the polar terminals 13 and cause a short circuit of the battery module 1, improving the safety of the battery module 1. It should be noted that if the insulating protective cover 14 completely wraps the polar terminals 13, it will make the electrical connection of such battery modules 1 more difficult. Therefore, in this embodiment, a slit is opened on the side wall of the insulating protective cover 14, and through this slit, the electrical connector can be connected to the polar terminals 13 of the single battery 12, thereby realizing electrical connection.

[0070] As Figure 1 and Figure 4 shown, in order to prevent the thermal runaway flue gas of the single battery 12 in an individual battery module 1 from diffusing to the entire energy storage device and causing safety problems, the thermal runaway flue gas of all battery modules 1 is converged by the flue gas converging pipe 2. After any single battery 12 in a battery module 1 undergoes thermal runaway, its thermal runaway flue gas can be discharged through the flue gas converging pipe 2, reducing the spread of thermal runaway. The flue gas converging pipe 2 in this embodiment includes a primary converging pipe 21 and a secondary converging pipe 22. The primary converging pipe 21 is connected to the battery modules 1 arranged in the same row, and the secondary converging pipe 22 is connected to each primary converging pipe 21. Figure 1 and Figure 4Only one row of battery modules 1 is provided exemplarily. If there are multiple rows of battery modules 1, the battery modules in each row are arranged in sequence from top to bottom. The secondary busbars 22 are all connected to the respective primary busbars 21, and the thermal runaway flue gas in each primary busbar 21 is centrally transported to the flue gas treatment unit.

[0071] As Figure 4 shown, in order to lead the thermal runaway flue gas out of the housing 11, an explosion vent pipe assembly 4 communicating with the inner cavity of the housing 11 is provided on the housing 11; one end of the explosion vent pipe assembly 4 communicates with the above-mentioned shared chamber, and the other end is connected to the primary busbar 21. Specifically, when connecting, the explosion vent pipe assembly 4 is arranged on the housing 11 and communicates with at least one of the electrolyte shared chamber and the gas shared chamber. When both the electrolyte shared chamber and the gas shared chamber are communicated with the explosion vent pipe assembly 4, two groups of explosion vent pipe assemblies 4 are provided on the housing, and the two groups of explosion vent pipe assemblies 4 are respectively communicated with the electrolyte shared chamber and the gas shared chamber. Subsequently, both groups of explosion vent pipe assemblies 4 are connected to the flue gas busbar 2. This setting enables the battery module to have two explosion vent channels. When any single battery undergoes 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 can be reduced in a short time, reducing the explosion risk.

[0072] The primary busbar 21 in this embodiment may specifically include the following structural forms.

[0073] First, a single integral pipe can be selected as the primary busbar 21, and a plurality of branch pipes connected to the explosion vent pipe assemblies 4 of each battery module 1 are provided thereon. During assembly, first, all the battery modules 1 are arranged along the length direction of the primary busbar 21, and then the respective branch pipes of the primary busbar 21 are connected to the explosion vent pipe assemblies 4 of the corresponding battery modules 1. When connecting, it is necessary to ensure the coaxiality between the branch pipe and the explosion vent pipe assembly 4. Due to the installation error of the explosion vent pipe assembly 4, the machining error of each branch pipe, and the spacing deviation between the battery modules 1, it is difficult to make the branch pipe and the explosion vent pipe assembly 4 coaxial, making it difficult to assemble the flue gas busbar 2 with each battery module 1.

[0074] Second, as Figure 5 and Figure 6As shown, the explosion vent pipe assembly 4 is designed as a split part, and the first-stage manifold 21 is also designed as a split part. The explosion vent pipe assembly 4 includes a first explosion vent member 41 and a second explosion vent member 42. The first explosion vent member 41 includes a first hollow pipe fitting 411 with an explosion vent film disposed therein and is connected to the outer shell 11. The second explosion vent member 42 is a tee pipe. Its first interface (vertical pipe section joint) is sealingly connected to the first explosion vent member 41, and the second interface and the third interface (two joints of the horizontal pipe section) are respectively used for connecting to the flexible pipe sections 211 that form the first-stage manifold 21. That is to say, the first-stage manifold 21 is spliced by the horizontal pipe sections of multiple tees and multiple flexible pipe sections 211. During assembly, each tee pipe section is fixed to the corresponding first explosion vent member 41 to form a battery module 1 with the explosion vent pipe assembly 4. Then, multiple battery modules 1 are arranged in a set direction. Finally, the adjacent two tees are connected by the flexible pipe sections 211. Due to the spliced first-stage manifold 21 in this embodiment and the middle connecting pipe section being a flexible pipe section 211, based on the deformation of the flexible pipe section 211, the installation error of the explosion vent pipe assembly 4 and the spacing deviation of the battery modules 1 can be compensated, reducing the installation difficulty of the first-stage manifold 21.

[0075] To further improve safety, insulation should be provided between the first-stage manifold 21 and the battery module 1. For example, flexible pipe sections 211 and / or tee pipe sections made of insulating and high-temperature resistant (temperature of thermal runaway flue gas) materials can be used, and an insulating pipe section can also be added between the first hollow pipe fitting 411 and the second explosion vent member 42. Specifically, as Figure 7 shown, the first explosion vent member 41 further includes a second hollow pipe fitting 412 connected to the first hollow pipe fitting 411. The material of the second hollow pipe fitting 412 is an insulating material. The second explosion vent member 42 is a union tee pipe, and the union joint of the second explosion vent member 42 is threadedly connected to the second hollow pipe fitting 412.

[0076] When the explosion vent pipe assembly 4 with an explosion vent film is specifically connected, it is applicable to a shared chamber communicating with the inner cavities of each single battery. Specifically, it is an electrolyte shared chamber 111 communicating with the electrolyte regions in the inner cavities of all single batteries 12, or a gas shared chamber communicating with the gas regions in the inner cavities of all single batteries 12. When the gas shared chamber 112 is a gas passage located between the top plate of the outer shell and each single battery, and this gas passage serves as a shared explosion vent passage, the outer shell is connected to the flue gas manifold through a sealing connection member. The sealing connection member includes a sealing connection pipe and a one-way valve or pressure valve provided on the sealing connection pipe, etc. One end of the sealing connection pipe is connected to the outer shell and communicates with the gas passage, and the other end is connected to the flue gas manifold. During the normal operation of the battery module, the sealing connection member disconnects the gas passage from the flue gas manifold to ensure that the inner cavity of the outer shell is in a closed state. When a thermal runaway occurs in the battery module, when the explosion vent part of any single battery 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 through the gas passage and then enters the subsequent flue gas treatment unit for treatment.

[0077] The above-mentioned flue gas manifold 2 converges the hot gas generated by each battery module 1 and centrally leads it to the subsequent flue gas treatment unit for treatment. However, in each of the above-mentioned battery modules 1, there is a certain amount of free electrolyte in the shared chamber. When the battery module 1 undergoes thermal runaway, when it is ejected together with the hot gas, there are certain safety hazards. Based on this, as Figure 1 shown, the flue gas treatment unit in this embodiment includes a liquid treatment device 3, which is connected to the outlet of the secondary manifold 22 and is mainly used to fully treat the electrolyte carried in the hot gas of the battery module 1 to prevent the vaporized electrolyte from continuing to decompose to generate combustible gases, thereby reducing the content of combustibles (electrolyte and combustible gases) in the hot gas.

[0078] As Figure 1 and Figure 8 shown, the liquid treatment device 3 in this embodiment includes M liquid treatment tanks 31 filled with a liquid treatment medium. The number of liquid treatment tanks 31 can be set according to the number and requirements of the battery modules 1 in the energy storage device. If there are multiple liquid treatment tanks 31, the multiple liquid treatment tanks 31 can be connected in series through a connecting pipeline 38. The shape of the liquid treatment tank 31 is not limited and can be a rectangular tank body, a circular tank body, an elliptical tank body, etc. Preferably, a circular tank body is used, and the circular tank body has good pressure-bearing performance.

[0079] The above-mentioned M liquid treatment tanks 31 can all be filled with a liquid treatment medium. Specifically, when filling, the liquid treatment medium is filled to about 2 / 3 of the inner cavity of the liquid treatment tank 31 to prevent the liquid treatment medium in the previous liquid treatment tank 31 from being squeezed into the next liquid treatment tank 31, resulting in poor treatment effects.

[0080] During actual use, the pressure of the thermal runaway flue gas at the initial explosion venting of the battery module is too high, and the liquid treatment medium in the last liquid treatment tank 31 may be squeezed out of the liquid treatment tank 31 by the thermal runaway flue gas. Based on this, the last liquid treatment tank 31 can be set as an empty tank. For example, the liquid treatment device 3 includes 9 liquid treatment tanks 31, among which, the 1st to 8th liquid treatment tanks 31 are filled with a liquid treatment medium, and the 9th liquid treatment tank 31 is an empty tank. When the pressure of the thermal runaway flue gas discharged from the battery module 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 31, and improve the safety of the liquid treatment device during use.

[0081] As Figure 8 shown, a flue gas inlet 32 and a flue gas outlet 33 are provided on the liquid treatment tank 31. The flue gas inlet 32 is used to input the thermal runaway flue gas into the liquid treatment tank 31, and the flue gas outlet 33 is used to discharge the treated thermal runaway flue gas. When specifically setting the flue gas inlet 32, it can be set at the top of the liquid treatment tank 31 or at the bottom of the liquid treatment tank 31. For the convenience of connecting each liquid treatment tank 31, the flue gas inlet 32 and the flue gas outlet 33 are preferably both set at the top of the liquid treatment tank 31. At this time, each liquid treatment tank 31 only needs to be connected at the top, which improves the connectability of the entire thermal runaway flue gas treatment device and the compactness of the pipeline layout. In addition, the above-mentioned connecting pipeline 38 can adopt a metal bellows. After being connected with the metal bellows, each liquid treatment tank 31 can be arranged according to the requirements of the installation space, meeting various installation requirements and saving installation space.

[0082] As Figure 8 shown, after the flue gas inlet 32 is set at the top of the liquid treatment tank 31, in order to make the thermal runaway flue gas fully contact with the liquid treatment medium in the liquid treatment tank 31, a drainage pipe 34 is connected to the flue gas inlet 32, and at least part of the drainage pipe 34 can be immersed in the liquid treatment medium. Optimally, the drainage pipe 34 preferably extends to the bottom of the liquid treatment tank 31 and can be completely immersed in the liquid treatment medium. When the thermal runaway flue gas passes through the liquid treatment tank 31, it fully contacts with the liquid treatment medium in the liquid treatment tank 31, 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.

[0083] As Figure 8As shown, a flow splitting portion 35 is provided at one end of the above-mentioned drainage pipe 34 immersed in the liquid treatment medium. The flow splitting portion 35 disperses and splits the thermal runaway flue gas and then reacts with the liquid treatment medium in the liquid treatment tank 31, so that the thermal runaway flue gas enters in a large flow rate and exits in a small flow rate, which is conducive to the dispersion of the thermal runaway flue gas, enables the thermal runaway flue gas to fully contact and react with the liquid treatment medium, and improves the treatment effect of the liquid treatment medium. The flow splitting portion 35 in this embodiment can be a copper foam column, which is convenient for installation and has a good effect of dispersing and splitting. Specifically, during installation, it is fixed to the port of the drainage pipe 34 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 dispersing and buffering effect on fluids. During use, it is processed into a columnar structure, and the thermal runaway flue gas passing through the drainage pipe 34 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 dispersing and buffering effect on the thermal runaway flue gas, so that the split thermal runaway flue gas can fully contact the liquid treatment medium.

[0084] As Figure 8 shown, in order to further enable the thermal runaway flue gas to fully react with the liquid treatment medium, a spiral baffle 37 is provided on the above-mentioned drainage pipe 34, or multiple baffle plates are provided on the drainage pipe 34. When the thermal runaway flue gas passes through the liquid treatment tank 31, the spiral baffle 37 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 32 of the liquid treatment tank 31, then enters the bottom of the liquid treatment medium through the drainage pipe 34, and then is dispersed by the copper foam column. During the process of rising from the bottom, the spiral baffle 37 or multiple baffle plates will make the thermal runaway flue gas fully contact the liquid treatment medium in the liquid treatment tank 31, so as to perform corresponding treatment. Specifically, when connecting, the spiral baffle 37 can be fixed on the drainage pipe 34. 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 34, and adjacent baffle plates are installed in a staggered manner.

[0085] Before the above-mentioned liquid treatment tank 31 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 31 during subsequent use. When the liquid treatment tank 31 is subjected to the pressure test for leak detection, generally, the empty liquid treatment tank 31 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 31, and then multiple liquid treatment tanks 31 are connected through the connecting pipeline 38. After multiple liquid treatment tanks 31 are connected, a second pressure test for leak detection needs to be carried out on the connecting pipeline 38 between the liquid treatment tanks 31. The two pressure tests for leak detection result in a low detection efficiency of the liquid treatment tank 31, and further reduce the assembly efficiency of the liquid treatment device 3.

[0086] AsFigure 8 As shown, in order to facilitate the injection of the liquid treatment medium and the pressure test for leakage detection of the liquid treatment tank 31, a three-way valve 36 is provided on the above-mentioned flue gas outlet 33. The three-way valve 36 can specifically be a three-way ball valve or the like. This three-way valve 36 can fill the liquid treatment medium after the pressure test for leakage detection of all the liquid treatment tanks 31 is completed. During specific connection, the first port of this three-way valve 36 is connected to the flue gas outlet 33, the second port is used to discharge the thermal runaway flue gas, and the third port is used to inject the liquid treatment medium.

[0087] After the pressure test for leakage detection of the above-mentioned liquid treatment tank 31 is completed, the liquid treatment medium is filled. This liquid treatment medium is mainly used to fully treat the electrolyte carried in the thermal runaway flue gas to prevent the vaporized electrolyte from continuing to decompose to produce combustible gases, thereby reducing the content of combustibles (electrolyte and combustible gases) in the thermal runaway flue gas. The specific substances that can be used for this liquid treatment medium are as follows:

[0088] 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 at the same time 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.

[0089] Second, the liquid treatment medium is an alkaline solution. The alkaline solution 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 already vaporized electrolyte from continuing to produce 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.

[0090] 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 to decompose, but also treats some of the reaction gases. The gas volume of the thermal runaway flue gas treated by this concentration of alkaline solution is greatly reduced. Therefore, compared with the organic solvent, the alkaline solution has a better treatment effect.

[0091] For alkaline solutions, generally, the higher the concentration, the better the treatment effect on thermal runaway flue gas. However, the applicant found that low-concentration alkaline solutions have a better treatment effect compared to high-concentration alkaline solutions. In particular, for alkaline solutions with a concentration of 0.05 - 0.5 mol / L, when thermal runaway flue gas passes through this concentration of alkaline solution, the amount of collected gas is the smallest, and its treatment effect is better than that of alkaline solutions with a concentration above 0.5 mol / L. Therefore, when using an alkaline solution to treat thermal runaway flue gas, overcoming the bias of the prior art, using a low-concentration alkaline solution to treat thermal runaway flue gas enables the alkaline solution to effectively treat thermal runaway flue gas.

[0092] Taking the alkaline solution as NaOH solution as an example, a large number of battery thermal runaway tests were carried out. 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 of 0.05 - 0.5 mol / L was the smallest. The treatment effect was significant after being treated with a NaOH solution with a concentration of 0.1 - 0.2 mol / L, and the treatment effect was the best after being treated with a 0.1 mol / L NaOH solution.

[0093] When transporting the thermal runaway flue gas into the NaOH solution, the NaOH solution reacts with acidic substances such as the electrolyte, 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 significantly reduced.

[0094] Table 1 Unprocessed full-charge 32650 battery runaway data

[0095]

[0096] Table 2 Treatment results of NaOH solutions with different concentrations

[0097]

[0098]

[0099] According to the above test data, when the thermal runaway flue gas of a fully charged 32650 battery was not treated at all after thermal runaway, 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 after thermal runaway, the generally collected gas volume was greater 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 after thermal runaway, 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 collected gas volume 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.

[0100] Example 2

[0101] As Figure 9 shown, the energy storage device provided in this example is similar to the energy storage device in Example 1. The difference from Example 1 is that the flue gas treatment unit in this example includes a liquid treatment device 3 and a solid treatment device 5 arranged in sequence. From the test results in Example 1, 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 5 can be used to treat the remaining gas, making the treated thermal runaway flue gas completely non-combustible.

[0102] As Figure 9 shown, the specific structure of the liquid treatment device 3 has been described in detail in Example 1 and will not be elaborated in this example. The solid treatment device 5 in this example is arranged at the rear end of the liquid treatment device 3 and is used to treat the thermal runaway flue gas treated by the liquid treatment device 3. The solid treatment device 5 includes at least one solid treatment tank 51. The number of solid treatment tanks 51 can be set according to the number and requirements of the battery modules in the energy storage device. If there are multiple solid treatment tanks 51, the multiple solid treatment tanks 51 can be connected in series. At this time, the flue gas inlet of the first solid treatment tank 51 is connected to the flue gas outlet 33 of the last liquid treatment tank 31 in the liquid treatment device 3. The specific structure of the solid treatment tank 51 is similar to that of the liquid treatment tank 31, and its interior is filled with a solid adsorption medium for treating the thermal runaway flue gas treated by the liquid treatment tank 31.

[0103] The solid adsorption medium in the above-mentioned solid treatment tank 51 can specifically be activated carbon, graphene, carbon nanotubes, graphite, alumina, montmorillonite, silicate, phosphate, porous glass, etc., and is used to treat the residual gas after the liquid treatment tank 31 processes it. For example, it adsorbs excess H2, CO, methane, ethylene, etc. Preferably, the above-mentioned solid adsorption medium selects 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.

[0104] Table 3 Adsorption test after the combination of NaOH solution and activated carbon

[0105]

[0106] Through the test data, it is found that the effect of using NaOH solution and activated carbon (activated carbon in No. 1 gas mask P-B-3) to treat the thermal runaway flue gas of the empty battery thermal runaway is very good. After multiple tests, it is found that the thermal runaway flue gas after the full-charge 32650 battery runs out of control 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-flammable.

[0107] The flue gas treatment system in this embodiment introduces the thermal runaway flue gas generated by the thermal runaway of the battery module into the liquid treatment tank 31 for treatment. The liquid treatment tank 31 specifically treats the electrolyte and part of the gas carried in the battery thermal runaway flue gas, preventing the vaporized electrolyte from continuing to decompose and react to generate gas, thereby reducing the gas production of the battery thermal runaway gas. Subsequently, the subsequent solid treatment tank 51 can complete the treatment of the thermal runaway flue gas with less solid adsorption medium. At the same time, the treated gas is not flammable, improving the safety of the energy storage device.

[0108] Example 3

[0109] The energy storage device in this embodiment is similar to the energy storage device in Example 1. The difference from Example 1 is that the flue gas treatment unit in this embodiment further includes an ignition device 6. As Figure 10 shown, the ignition device 6 is arranged at the rear end of the liquid treatment device 3 and performs controllable ignition treatment on the thermal runaway flue gas treated by the liquid treatment device 3. The above-mentioned ignition device 6 can adopt the structures disclosed in Chinese patents CN220324645U, CN219453979U, CN218523576U, CN218498146U, CN218414927U, etc.

[0110] In some embodiments, the flue gas treatment unit may also only include the ignition device 6. The thermal runaway flue gas generated by the battery module 1 is directly transported to the ignition device 6 through the flue gas manifold 2, and the ignition device 6 directly conducts individual ignition treatment on all the thermal runaway flue gas.

[0111] As Figure 10 shown, the above-mentioned 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 33 of the Mth liquid treatment tank 31 in the liquid treatment device. 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, etc. When set to multiple groups, it can not only fully ignite the thermal runaway flue gas to ensure reliable ignition, but also avoid the safety hazards caused by the inability to reliably ignite the thermal runaway flue gas when a single ignition component fails or malfunctions.

[0112] As Figure 10 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 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 has a thermal runaway. Subsequently, the thermal runaway flue gas treated by the liquid treatment device is transported to the exhaust pipe 62 by the flue gas pipeline 61, 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 through the trigger 64 or can also be turned on through the BMS (Battery Management System). When turned on through the trigger 64, the trigger 64 can be sensors of different structures, and 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-mentioned trigger 64 can be at least one of a pressure sensor, a gas sensor or a temperature sensor. 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, 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 through the BMS, the BMS monitors the voltage, current and temperature of each battery module in the energy storage device in real time. When any battery module has a thermal runaway and the voltage, voltage and temperature exceed the threshold, the igniter 63 is started.

[0113] The structure of the above-mentioned igniter 63 can be various. For example, an existing arc igniter or resistance wire igniter can be specifically adopted, etc. 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.

[0114] When a thermal runaway occurs in the battery module, the thermal runaway flue gas generated by the thermal runaway of the battery module enters the liquid treatment device 3 through the flue gas manifold 2. The liquid treatment device 3 treats the electrolyte and some gases carried in the battery thermal runaway flue gas. Subsequently, the ignition device 6 performs a controllable ignition treatment on the thermal runaway flue gas treated by the liquid treatment device 3 to reduce the potential safety hazards generated after the thermal runaway flue gas is discharged.

[0115] Embodiment 4

[0116] The energy storage device in this embodiment is similar to the energy storage devices in Embodiment 1, Embodiment 2, and Embodiment 3. The difference is that the flue gas treatment unit in this embodiment further includes a buffer device 7. The buffer device 7 is arranged between the flue gas manifold 2 and the flue gas treatment unit to buffer the thermal runaway flue gas entering the flue gas treatment unit.

[0117] As Figure 11 and Figure 12 shown, the buffer device 7 includes N buffer tanks 71. Each buffer tank 71 is provided with a smoke inlet 72 and a smoke outlet 73 communicating with its inner cavity. The smoke inlet 32 of the first liquid treatment tank 31 is connected to the smoke outlet 73 of the Nth buffer tank 71, where N is an integer greater than or equal to 1. Figure 11 is a schematic diagram of the flue gas treatment unit including the buffer device 7 and the liquid treatment device 3, with the buffer device 7 arranged at the front end of the liquid treatment device 3. Figure 12 is a schematic diagram of the flue gas treatment unit including the buffer device 7, the liquid treatment device 3, and the ignition device 6, with the buffer device 7 arranged at the front end of the liquid treatment device 3 and the ignition device 6 arranged at the rear end of the liquid treatment device 3. In other embodiments, the buffer device 7 can also be arranged at the front end of the ignition device 6.

[0118] In the above buffer device 7, the number of buffer tanks 71 can be set according to the number and requirements of the battery modules 1. If there are multiple buffer tanks 71, the multiple buffer tanks 71 can be connected in series through connecting pipelines. The shape of the buffer tank 71 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, as the circular tank body has good pressure-bearing performance.

[0119] The number of buffer tanks 71 in this embodiment is 1. This buffer tank 71 is an empty tank body without filling substances inside. It is arranged between the flue gas manifold 2 and the flue gas treatment unit and mainly has the following functions:

[0120] First, buffer the thermal runaway flue gas;

[0121] A buffer tank 71 is provided in front of the flue gas treatment unit. The buffer tank 71 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 enters the liquid treatment tank 31 or the ignition device 6 at a relatively stable flow rate. The liquid treatment medium can treat the thermal runaway flue gas more fully. Or, when the thermal runaway flue gas is ignited by the ignition device, the combustion flame is relatively stable, avoiding the defect that the thermal runaway flue gas with instantaneous large pressure quickly passes through the liquid treatment medium and the thermal runaway flue gas cannot be fully treated, and improving the treatment effect of the liquid treatment medium;

[0122] Second, collect the electrolyte in the thermal runaway flue gas;

[0123] There is a certain amount of free electrolyte in the battery module with a shared chamber. This free electrolyte is ejected together with the thermal runaway flue gas when the battery module undergoes thermal runaway. Especially when the explosion venting area is set at the bottom of the outer shell, almost all the free electrolyte inside the shared chamber is ejected with the thermal runaway flue gas. A buffer tank 71 is provided in front of the liquid treatment device. While buffering the thermal runaway flue gas, the buffer tank 71 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 71, thereby reducing the usage amount of the liquid treatment medium in the subsequent liquid treatment device;

[0124] When the battery module undergoes thermal runaway, almost all the free electrolyte inside the battery module is ejected with the thermal runaway flue gas. The electrolyte is ignited together with the combustible gas. At this time, when the liquid electrolyte carried in the thermal runaway flue gas burns, hazards such as flame sputtering may occur. At the same time, when the thermal runaway flue gas is ignited, the electrolyte and the combustible gas in the thermal runaway flue gas participate in combustion simultaneously, generating a large amount of combustion flames. The large amount of combustion flames may affect the devices near the ignition device 6, posing a certain safety hazard. A buffer tank 71 is provided in front of the ignition device 6. While buffering the thermal runaway flue gas, the buffer tank 71 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 71. This can not only prevent the vaporized electrolyte from continuing to undergo decomposition reactions to generate combustible gas and reduce the amount of combustible gas, but also, when the subsequent thermal runaway flue gas is ignited, only the combustible gas burns (the electrolyte has been collected by the buffer tank), making the size of the flame when the thermal runaway flue gas is ignited smaller and reducing the safety hazard to the surrounding environment;

[0125] Third, remove impurities from the thermal runaway flue gas;

[0126] When a thermal runaway occurs in the battery module, the temperature inside each single battery is approximately between 140°C and 850°C. At this temperature, fusible parts such as diaphragms, plastic films, and plastic components inside the single battery are melted by high temperature. During the process of the above molten substances being ejected from the battery cavity through the hot runaway flue gas and flowing through the flue gas manifold 2 to the subsequent hot runaway flue gas treatment device, as the temperature of the hot runaway flue gas decreases, the molten substances gradually solidify and agglomerate, which easily blocks the pipelines in the flue gas treatment unit. At this time, after adding the buffer tank 71, impurities such as molten substances discharged with the hot runaway flue gas will be deposited and collected in the buffer tank 71 when the hot runaway flue gas buffers in the buffer tank 71, avoiding the problem of blockage of the subsequent pipelines;

[0127] Fourth, collect the liquid treatment medium for backwashing;

[0128] When a thermal runaway occurs in the battery module, the instantaneously ejected hot runaway flue gas has a relatively high pressure. This high-pressure hot runaway flue gas enters the liquid treatment tank 31 through the flue gas manifold 2. Since the liquid treatment tank 31 is filled with a liquid treatment medium and is provided with a shunt portion 35, there is a situation where the hot runaway flue gas cannot be discharged from the liquid treatment tank 31 in time, resulting in overpressure in the liquid treatment tank 31. At this time, the following phenomena may occur: the liquid treatment medium in the liquid treatment tank 31 is backwashed by the high-pressure gas in the liquid treatment tank 31 into the flue gas manifold 2, and the flue gas manifold 2 is blocked, causing the subsequent generated hot runaway flue gas to be unable to be smoothly discharged into the liquid treatment tank 31 through the flue gas manifold 2;

[0129] By adding a buffer tank 71 in front of the liquid treatment tank 31, when the liquid treatment medium in the liquid treatment tank 31 undergoes backwashing, the liquid treatment medium is backwashed and collected in the front buffer tank 71 and will not flow into the flue gas manifold 2, thereby avoiding the blockage problem of the flue gas manifold 2 and enabling the hot runaway flue gas to be smoothly discharged into the liquid treatment device for treatment.

[0130] Such as Figure 11As shown in the figure, an inlet smoke port 72 and an outlet smoke port 73 communicating with the inner cavity are provided on the above-mentioned buffer tank 71. The inlet smoke port 72 is mainly used to connect with the flue gas confluence pipe 2, and the flue gas confluence pipe 2 transports the thermal runaway flue gas generated by the thermal runaway of the battery module into the buffer tank 71. The outlet smoke port 73 is mainly used to discharge the thermal runaway flue gas in the buffer tank 71. When specifically setting the above-mentioned inlet smoke port 72 and outlet smoke port 73, they can be set on the side wall of the buffer tank 71 or on the top of the buffer tank 71. In this embodiment, both the inlet smoke port 72 and the outlet smoke port 73 are set on the top of the buffer tank 71. Setting the inlet smoke port 72 on the top of the buffer tank 71, firstly, can make the solid impurities and electrolyte carried by the thermal runaway flue gas deposit at the bottom of the buffer tank 71 as much as possible under the action of gravity; secondly, it is difficult for the liquid in the buffer tank 71 to be squeezed into the front flue gas confluence pipe 2 through the inlet smoke port 72 at the top. Setting the outlet smoke port 73 on the top of the buffer tank 71, firstly, can prevent the solid impurities and electrolyte carried by the thermal runaway flue gas from being discharged smoothly; secondly, can make the gas in the thermal runaway flue gas be discharged from the buffer tank 71 smoothly.

[0131] In addition, as Figure 11 shown, a drain valve 74 can also be provided at the bottom of the above-mentioned buffer tank 71 to drain the liquid in the buffer tank 71 in time. To facilitate the standardization and integration of the energy storage device, the buffer tank 71 can adopt a structure similar to that of the liquid treatment tank 31. At the same time, a three-way valve can also be installed on the outlet smoke port 73 of the buffer tank 71, and the liquid treatment tank 31 and the buffer tank 71 can be subjected to a pressure test for leak detection at the same time.

[0132] Embodiment 5

[0133] The energy storage device in this embodiment is similar to the energy storage devices in Embodiment 1, Embodiment 2, Embodiment 3 and Embodiment 4. The difference is that the flue gas treatment system in this embodiment further includes at least one safety device.

[0134] When using the devices in the above-mentioned Embodiment 1, Embodiment 2, Embodiment 3 and Embodiment 4 to treat the thermal runaway flue gas generated by the battery module, the following problems may exist:

[0135] First, if multiple battery modules 1 have thermal runaway at the same time, due to the excessive pressure of the thermal runaway flue gas, the explosion relief part of the battery module (i.e., the explosion relief film in the explosion relief pipe assembly 4) may be opened in the reverse direction, affecting the battery modules that have not had thermal runaway and posing a safety hazard. Or, the seal at the connection of the flue gas confluence pipe 2 may be damaged, causing leakage of the flue gas confluence pipe 2 and posing a safety hazard;

[0136] Second, since the liquid treatment tank 31 is filled with a liquid treatment medium and is provided with a flow dividing portion 35, there is a situation where the thermal runaway flue gas cannot be discharged from the liquid treatment tank 31 in time, and the thermal runaway flue gas accumulates and is blocked in the flue gas converging pipe 2. When the pressure is too high, the explosion relief portion of the battery module (i.e., the explosion relief membrane in the explosion relief pipe assembly 4) is opened in the reverse direction, which affects the battery modules that have not experienced thermal runaway and poses a safety hazard. Or, it damages the seal at the connection of the flue gas converging pipe 2, causing leakage in the flue gas converging pipe 2 and posing a safety hazard.

[0137] Based on this, the energy storage device of this embodiment further includes at least one safety device. This safety device can discharge the thermal runaway flue gas through the safety device when the pressure of the thermal runaway flue gas in the flue gas converging pipe 2 is too high, so as to avoid the safety hazard caused by excessive pressure in the flue gas converging pipe 2 and improve the safety of the energy storage device.

[0138] As Figure 13 shown, each safety device 8 includes a safety pipeline 81 and a safety discharge portion 82; the inlet of the safety pipeline 81 is connected to the flue gas converging pipe 2, and the outlet is connected to the external environment. Or, the outlet of the safety pipeline 81 is connected to the flue gas outlet 33 of the Mth liquid treatment tank 31. Or, the outlet of the safety pipeline 81 is connected to the flue gas outlet of the last solid treatment tank 51. Or, the outlet of the safety pipeline 81 is connected to the flue gas pipeline 61 of the ignition device 6. The safety discharge portion 82 is provided on the safety pipeline 81, and its opening pressure is less than the opening pressure of the explosion relief membrane (the explosion relief pipe assembly 4 is the explosion relief portion of the battery module) in the explosion relief pipe assembly 4 of the battery module. This safety device 8 is used to discharge the thermal runaway flue gas from the safety pipeline 81 when the pressure of the thermal runaway flue gas in the flue gas converging pipe 2 is too high and poses a safety hazard, so as to avoid the thermal runaway flue gas from affecting the batteries that have not experienced thermal runaway or affecting the sealing performance of the connection of the flue gas converging pipe 2, and improve the safety during the use of the energy storage device.

[0139] The above-mentioned safety discharge portion 82 can be specifically implemented by the following structures: First, use an explosion relief membrane or an explosion relief valve; the explosion relief membrane or the explosion relief valve is installed on the safety pipeline 81. Second, use a safety valve, and the safety valve can open at a set pressure; this safety valve can use a pressure valve, and the pressure valve can open automatically at a certain pressure; the pressure valve has a set opening threshold, and when the pressure in the flue gas converging pipe 2 exceeds this threshold, the pressure valve opens automatically, with relatively high reliability. In addition, the installation of the safety valve is also relatively convenient. Third, as Figure 13As shown, a pressure measurement device 821 and a control valve 822 are adopted; the pressure measurement device 821 is used to monitor the pressure of the gas in the flue gas manifold 2, and when the pressure of the gas in the flue gas manifold 2 exceeds the threshold value, the control valve 822 is opened. Specifically, the pressure measurement device 821 can adopt a pressure sensor, and the control valve 822 is a solenoid valve. The solenoid valve is signal-connected to the pressure measurement device 821, and the pressure measurement device 821 controls the opening of the solenoid valve according to the pressure in the flue gas manifold 2.

Claims

1. An energy storage device, characterized in that: comprising a flue gas treatment system and at least one battery module; The battery module comprises a shell and a plurality of single cells arranged in the shell in the same direction; the 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; a avoidance hole is provided on the top plate of the shell corresponding to the polarity terminal of each single cell; the polarity terminal of each single cell extends out of the avoidance hole, and the top plate area of ​​the shell corresponding to the avoidance hole is fixedly sealed with the shell of the single cell; The flue gas treatment system includes a flue gas manifold and a flue gas treatment unit. The flue gas manifold is used to transport the thermal runaway flue gas generated by each battery module to the flue gas treatment unit. The flue gas treatment unit is used to treat the thermal runaway flue gas.

2. The energy storage device according to claim 1, characterized in that: The shared chamber is an electrolyte shared chamber, which is connected to the electrolyte area of ​​each single battery. The shell is provided with an explosion relief pipe assembly connected to the electrolyte shared chamber, and the explosion relief pipe assembly is connected to the flue gas manifold.

3. The energy storage device according to claim 1, characterized in that: The shared chamber is a gas shared chamber, which is connected to the gas area of ​​each single battery. The shell is provided with an explosion relief pipe assembly connected to the gas shared chamber, and the smoke manifold is connected to the explosion relief pipe assembly.

4. The energy storage device according to claim 1, 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 battery, the gas shared chamber is connected to the gas area of ​​each single battery, an explosion-proof pipe assembly is arranged on the shell, at least one of the gas shared chamber and the electrolyte shared chamber is connected to the explosion-proof pipe assembly, and the smoke manifold is connected to the explosion-proof pipe assembly.

5. The energy storage device according to claim 1, 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-proof part of each single cell. When the explosion-proof part of any single cell is broken by the thermal runaway smoke in the inner cavity, the gas area of ​​the single cell is connected to the gas channel. An explosion-proof pipe assembly is arranged on the outer shell. At least one of the gas shared chamber and the electrolyte shared chamber is connected to the explosion-proof pipe assembly, and the smoke manifold is connected to the explosion-proof pipe assembly.

6. The energy storage device according to any one of claims 1 to 5, characterized in that: The flue gas treatment unit includes at least one of a liquid treatment device, a solid treatment device, a flue gas cooling device and an ignition device; The liquid treatment device is mainly used to treat the electrolyte and gas in the thermal runaway flue gas; The flue gas cooling device is mainly used to cool down thermal runaway; The solid treatment device is mainly used to adsorb the gas in the thermal runaway flue gas; The ignition device is used to ignite the thermal runaway flue gas.

7. The energy storage device according to claim 6, characterized in that: The liquid treatment device includes M liquid treatment tanks, each of which is provided with a smoke inlet and a smoke outlet, the first liquid treatment tank to the M-1th liquid treatment tank are filled with liquid treatment medium, and the Mth liquid treatment tank is an empty tank, wherein M is an integer greater than or equal to 2.

8. The energy storage device according to claim 7, characterized in that: The flue gas treatment unit 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.

9. The energy storage device according to claim 8, characterized in that: The liquid treatment medium is an alkaline solution, and the alkaline solution is a 0.05-0.5 mol / L NaOH solution.

10. The energy storage device according to claim 6, characterized in that: The flue gas treatment system also includes a buffer device, which includes at least one buffer tank. The buffer tank is provided with a smoke inlet and a smoke outlet connected to its inner cavity. The buffer device is arranged between the smoke manifold and the smoke treatment unit, and is used for buffering the thermal runaway smoke.

11. The energy storage device according to claim 10, characterized in that: The flue gas treatment system also includes a safety device, which includes a safety pipeline and a safety discharge part; the inlet of each safety pipeline is connected to the flue gas manifold, and the outlet of the safety pipeline is connected to the external environment; the safety discharge part is arranged on the safety pipeline, and its opening pressure is less than the opening pressure of the battery module explosion relief part.

12. The energy storage device 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 in each primary manifold to the flue gas treatment unit.

13. The energy storage device according to claim 12, characterized in that: 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 pipe connected to the housing, and an explosion relief membrane is arranged in the first hollow pipe; 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.

14. The energy storage device according to claim 13, 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.

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