Energy storage device and electric equipment

Abstract

The invention discloses an energy storage device and electric equipment. The energy storage device comprises a base, a first upper cover, a battery module and a gas guide structure. A battery cavity is defined by the first upper cover and the base. The first upper cover is provided with at least one ventilation structure which is provided with at least one first through hole. The battery module comprises a single battery which is provided with an anti-explosion valve hole. And the position of the anti-explosion valve hole of the battery module corresponds to the position of the first through hole of the ventilation structure. The air guide structure comprises at least one air guide assembly, each air guide assembly comprises a valve and an air guide sleeve made of a first shape memory alloy, and the at least one valve of the air guide structure is arranged at an orifice of the at least one first through hole of the ventilation structure. The valve is used for closing or opening the first through hole. When the air guide sleeve is in the first state, the length of the air guide sleeve is L1. When the air guide sleeve is in the second state, the length of the air guide sleeve is L2, air guide channels communicated with the corresponding first through holes and the corresponding anti-explosion valve holes are formed in the air guide sleeve, and L1 is smaller than L2.

Description

Technical Field

[0001] The present application relates to the field of energy storage technology, and in particular to an energy storage device and electrical equipment. Background Art

[0002] The battery pack includes a box body and a battery module arranged in the box body. The battery module includes multiple single cells arranged side by side. When one of the single cells experiences thermal runaway, high-temperature and high-pressure gas will be generated inside the single cell. The high-temperature and high-pressure gas will instantly break through the explosion-proof valve of the single cell and diffuse into the battery pack. The diffused high-temperature gas will diffuse to the adjacent single cells, causing the temperature of the adjacent single cells to rise sharply, thereby increasing the risk of thermal runaway of the adjacent single cells. Summary of the invention

[0003] The embodiments of the present application provide an energy storage device and an electrical device to solve the problem that thermal runaway of one or more single cells may cause thermal runaway of adjacent single cells.

[0004] The energy storage device of the embodiment of the present application includes:

[0005] Base;

[0006] A first upper cover is connected to the base, and the first upper cover and the base form a battery cavity; the first upper cover has at least one ventilation structure, the ventilation structure has at least one first through hole, and the first through hole passes through the inner wall surface and the outer wall surface of the first upper cover;

[0007] at least one battery module, disposed in the battery cavity, and comprising a plurality of single cells, each of which has an explosion-proof valve hole; along a first direction, the position of the explosion-proof valve hole of at least one of the single cells of the battery module corresponds to the position of at least one of the first through holes of the ventilation structure; the first direction is the height direction of the single cells; and

[0008] At least one air guide structure, the air guide structure includes at least one air guide component, the air guide component includes a valve and an air guide sleeve made of a first shape memory alloy, the valve of at least one air guide component of the air guide structure is respectively arranged at the orifice of at least one first through hole of the ventilation structure, and the valve has a closed state of closing the first through hole and an open state of opening the first through hole; the air guide sleeve is located in the battery cavity, and along the first direction, the position of the air guide sleeve of at least one air guide component of the air guide structure corresponds to the position of the explosion-proof valve hole of at least one single battery of the battery module; one end of the air guide sleeve is connected to the first upper cover or the valve, and is extended along the first direction; the air guide sleeve has a first state and a second state, when the air guide sleeve is in the first state, the length of the air guide sleeve is L1, when the air guide sleeve is in the second state, the length of the air guide sleeve is L2, and an air guide channel is formed inside, and the air guide channel is respectively connected to the corresponding first through hole and the corresponding explosion-proof valve hole, L1<L2.

[0009] The energy storage device of the embodiment of the present application is provided with a valve and a gas guide sleeve made of the first shape memory alloy. When a single cell in the energy storage device has thermal runaway, the gas guide sleeve corresponding to the single cell can directly guide the high-temperature and high-pressure gas ejected from the single cell out of the battery pack, and try to avoid the high-temperature and high-pressure gas from spreading to other areas in the battery cavity, thereby avoiding the thermal runaway of other adjacent single cells caused by the thermal runaway of a single cell, reducing the accumulation of pressure inside the battery cavity, and reducing the risk of explosion. In addition, since the gas guide sleeve is made of the first shape memory alloy, it can automatically deform when subjected to high temperature to achieve the function of gas conduction, and can automatically return to its original state when the temperature returns to normal temperature, so the upper cover and the gas guide assembly can be reused, saving costs.

[0010] According to some embodiments of the present application, when the air guide sleeve is in the second state, the air guide sleeve covers the edge of the opening of the explosion-proof valve hole of the single battery.

[0011] In the embodiment of the present application, when thermal runaway occurs in a single cell, the gas guide sleeve extends and covers the edge of the opening of the explosion-proof valve hole of the single cell. The gas guide sleeve seals the edge of the opening of the explosion-proof valve hole to ensure that high-temperature and high-pressure gas can only flow into the gas guide channel and will not diffuse outward.

[0012] According to some embodiments of the present application, the initial phase transition temperature of the first shape memory alloy is equal to the thermal runaway initial temperature of the single battery.

[0013] In the embodiment of the present application, the initial phase change temperature of the first shape memory alloy is set to be equal to the thermal runaway starting temperature of the single cell, which can avoid blocking the explosion-proof valve hole of the single cell due to premature elongation of the gas guide sleeve, resulting in poor exhaust. Specifically, when the internal pressure of the single cell increases and causes the explosion-proof valve to open, if the temperature of the gas ejected at this time has not reached the thermal runaway starting temperature of the single cell, the gas guide sleeve remains in its original state and does not elongate. At this time, there is enough exhaust space above the explosion-proof valve hole of the single cell, so that the gas inside the single cell can quickly diffuse to the area where the adjacent single cell is located, and the speed of gas discharge from the inside of the single cell and the speed of diffusion to the surrounding are faster, reducing the risk of explosion of the single cell. At the same time, since the temperature of the gas ejected from the single cell at this time is low, the temperature rise of the adjacent single cell is also small, and the adjacent single cell will not cause thermal runaway. It can be seen that setting the initial phase change temperature of the first shape memory alloy to be equal to the thermal runaway starting temperature of the single cell not only ensures that the pressure relief speed of the single cell in the early stage of valve opening is not affected, but also reduces the influence of high temperature and high pressure gas on the temperature rise of the adjacent single cell.

[0014] According to some embodiments of the present application, the first shape memory alloy is a thermal elongation shape memory alloy.

[0015] According to some embodiments of the present application, the air guide sleeve includes a sleeve and a convex ring, the sleeve is connected to the first upper cover or the valve, and the convex ring is convexly arranged on the outer peripheral side of the sleeve;

[0016] The side surface of the sleeve facing the single cell is a first surface, the side surface of the convex ring facing the single cell is a second surface, the first surface is flush with the second surface and forms an annular covering surface;

[0017] When the air guide sleeve is in the second state, the annular covering surface covers the opening edge of the explosion-proof valve hole of the single battery.

[0018] In the embodiment of the present application, a convex ring is provided at one end of the sleeve away from the valve, and the first surface of the sleeve and the second surface of the convex ring form an annular covering surface. When the air guide sleeve is in the second state, the annular covering surface covers the edge of the orifice of the explosion-proof valve hole of the single cell. The annular covering surface increases the contact area between the air guide sleeve and the single cell, further reducing the risk of high-temperature and high-pressure gas ejected from the single cell diffusing outward from the gap between the air guide sleeve and the single cell.

[0019] According to some embodiments of the present application, the orthographic projection of the air guide sleeve on a target plane is annular and is defined as a first projection, the orthographic projection of the explosion-proof valve hole of the single cell corresponding to the air guide sleeve on the target plane is a second projection, and the second projection is located within the area enclosed by the inner circle of the first projection; wherein the target plane is perpendicular to the first direction.

[0020] In an embodiment of the present application, the second projection is located within the area enclosed by the inner circle of the first projection. When the air guide sleeve is in the second state, the air guide sleeve can cover the explosion-proof valve hole as a whole, so that the high-temperature gas can quickly enter the preset air guide channel and prevent the high-temperature gas from diffusing to other areas of the battery cavity.

[0021] According to some embodiments of the present application, the orthographic projection of the air guide sleeve on a target plane is annular and is defined as a first projection, the orthographic projection of the first through hole corresponding to the air guide sleeve on the target plane is a third projection, and the third projection is located in the area enclosed by the inner circle of the first projection, or the boundary of the third projection coincides with the inner circle of the first projection; wherein the target plane is perpendicular to the first direction.

[0022] In the embodiment of the present application, the third projection is located within the area enclosed by the inner circle of the first projection, or the boundary of the third projection coincides with the inner circle of the first projection. When the air guide sleeve is in the second state, the air guide sleeve will not block the first through hole, and the high-temperature gas can pass through the first through hole at a larger flow rate and enter the hollow cavity, thereby improving the pressure relief capacity of the air guide channel.

[0023] According to some embodiments of the present application, the energy storage device further includes:

[0024] a second upper cover connected to the first upper cover, and the second upper cover and the first upper cover form a hollow cavity, the second upper cover has a second through hole, the second through hole and the first through hole are both connected to the hollow cavity; when the valve is in the open state, the battery cavity is connected to the hollow cavity through the second through hole; and

[0025] The box cover explosion-proof valve is connected to the second upper cover and seals the second through hole.

[0026] In the embodiment of the present application, the high-temperature and high-pressure gas ejected from the single battery enters the hollow cavity through the gas guide sleeve, and then breaks through the explosion-proof valve of the box cover to be discharged. The channel for the high-temperature and high-pressure gas to be discharged to the outside of the battery cavity is the hollow cavity, which prevents the high-temperature gas from diffusing in the battery cavity and reduces the risk of high-voltage arcing of the parts inside the energy storage device under the action of the charged high-temperature airflow.

[0027] According to some embodiments of the present application, the valve is a one-way valve and is configured to allow fluid to enter the hollow cavity from the battery cavity through the one-way valve, while prohibiting fluid from entering the battery cavity from the hollow cavity through the one-way valve.

[0028] In the embodiment of the present application, the arrangement of the one-way valve ensures that the high-temperature gas ejected from the single cell that has thermal runaway can only enter the hollow cavity from the battery cavity, and cannot flow back from the hollow cavity to the battery cavity, thereby preventing the gas from flowing back to the area where other single cells are located in the battery cavity, thereby preventing other single cells from being affected by heat.

[0029] According to some embodiments of the present application, the one-way valve comprises:

[0030] A valve body is mounted on the second upper cover and penetrates the first through hole; the valve body has a valve cavity, the inner wall surface of the valve cavity has a valve port, the portion of the valve body located between the first upper cover and the second upper cover also has an air outlet, the air outlet is communicated with the hollow cavity and the valve cavity; the portion of the valve body extending into the battery cavity also has an air inlet, the air inlet is communicated with the valve port;

[0031] A blocking member, movably disposed in the valve cavity, for closing or opening the valve port;

[0032] An elastic member is disposed in the valve cavity and is used to provide an elastic force for closing the valve port to the blocking member.

[0033] According to some embodiments of the present application, the air guide sleeve is sleeved on the outer periphery of the portion of the valve body extending into the battery cavity, and the air inlet is located inside the air guide sleeve.

[0034] According to some embodiments of the present application, the valve is a phase change member made of a second shape memory alloy, the phase change member is connected to the inner wall surface of the second upper cover, and the air guide sleeve is connected to the inner wall surface of the first upper cover;

[0035] The length of the phase change element when in the closed state is L3 and closes the first through hole, and the length of the phase change element when in the open state is L4 and opens the first through hole, L3>L4.

[0036] According to some embodiments of the present application, a starting phase transition temperature of the second shape memory alloy is lower than a starting phase transition temperature of the first shape memory alloy.

[0037] In the embodiment of the present application, since the starting phase change temperature of the second shape memory alloy is lower than the starting phase change temperature of the first shape memory alloy, when thermal runaway occurs, the phase change element will begin to shrink before the gas guide sleeve. In this way, when the high-temperature gas enters the gas guide channel of the gas guide sleeve, the phase change element is already in an open state of opening the first through hole. At this time, the high-temperature gas can smoothly pass through the first through hole and enter the hollow cavity, thereby avoiding the situation where the gas guide sleeve has been extended while the phase change element still remains in a state of closing the first through hole.

[0038] According to some embodiments of the present application, the second shape memory alloy is a thermally shortened shape memory alloy.

[0039] The electric equipment of the embodiment of the present application comprises the energy storage device described in any one of the above items, and the energy storage device supplies power to the electric equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The accompanying drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present application, and together with the specification are used to explain the principles of the present application. Obviously, the accompanying drawings described below are only some embodiments of the present disclosure, and for ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0041] Figure 1 Shown is a structural schematic diagram of a household energy storage system.

[0042] Figure 2 Shown is a three-dimensional schematic diagram of an energy storage device according to the first embodiment of the present application.

[0043] Figure 3 It is shown that Figure 2 Schematic diagram of the decomposition.

[0044] Figure 4 Shown is along Figure 3 Schematic diagram obtained after cutting the upper lid along the AA cutting line.

[0045] Figure 5 Shown is along Figure 2 Schematic diagram obtained after cutting the battery pack along the BB cutting line.

[0046] Figure 6 It is shown that Figure 5 Enlarged view of point X1 in the middle.

[0047] Figure 7 Shown is a three-dimensional schematic diagram of the gas guide sleeve and the valve after assembly.

[0048] Figure 8 What is shown is a schematic diagram of the positional relationship between the first projection and the second projection.

[0049] Fig. 9 Shown is a schematic diagram of the positional relationship between the third projection and the fourth projection.

[0050] Fig.10 Shown is a schematic diagram of a single cell of the energy storage device of the first embodiment of the present application when thermal runaway does not occur.

[0051] Fig.11 The diagram shows the flow of gas when thermal runaway occurs in one of the single cells in the energy storage device of the first embodiment of the present application.

[0052] Fig.12 Shown is a schematic diagram of an energy storage device according to a second embodiment of the present application, in which no thermal runaway occurs in the single battery.

[0053] Fig.13 Shown is a schematic diagram of an energy storage device according to a second embodiment of the present application, in which a single cell undergoes thermal runaway.

[0054] Fig.14 Shown is a schematic diagram of an energy storage device according to the third embodiment of the present application.

[0055] Fig.15 Shown is a schematic diagram of an electrical device according to an embodiment of the present application.

[0056] The reference numerals are described as follows:

[0057] 1. Energy storage device; 2. Electric energy conversion device; 3. User load; 4. Electrical equipment;

[0058] 100, base; 100a, battery cavity;

[0059] 200, upper cover; 210, first upper cover; 210a, ventilation structure; 211, first through hole; 220, second upper cover; 221, second through hole; 222, threaded hole; 230, hollow cavity; 240, explosion-proof valve of box cover;

[0060] 300, battery module; 310, single battery; 311, explosion-proof valve hole;

[0061] 400, air guide structure; 400a, air guide assembly; 410, valve; 410a, one-way valve; 410b, phase change member; 411, valve body; 4111, valve cavity; 4112, valve port; 4113, air outlet; 4114, air inlet; 412, blocking member; 413, elastic member; 414, valve seat; 420, air guide sleeve; 420a, sleeve; 420b, convex ring; 4221, first surface; 423, air guide channel; 424, second surface; 425, annular covering surface;

[0062] 500, cold plate;

[0063] D1, first direction; D2, second direction; D3, third direction;

[0064] S1, first projection; S2, second projection; S3, third projection. DETAILED DESCRIPTION

[0065] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this application will be comprehensive and complete and fully convey the concepts of the example embodiments to those skilled in the art. The same reference numerals in the figures represent the same or similar structures, and thus their detailed description will be omitted.

[0066] It is understood that the terms "including" and "having" and any variations thereof in the embodiments of the present application are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units that are not listed, or may optionally include other steps or components that are inherent to these processes, methods, products, or devices.

[0067] Since the energy people need is highly temporal and spatial, in order to rationally utilize energy and improve energy utilization, it is necessary to use a medium or device to store one form of energy in the same way or convert it into another form of energy, and then release it in a specific form of energy based on future application needs.

[0068] At present, energy storage (i.e. energy storage) has a wide range of application scenarios, including power generation side energy storage, grid side energy storage, renewable energy grid-connected energy storage and user side energy storage. The corresponding types of energy storage devices include:

[0069] (1) Large energy storage containers used in grid-side energy storage scenarios can serve as high-quality active and reactive power regulation power sources in the grid, achieve load matching of electric energy in time and space, enhance the ability to absorb renewable energy, and are of great significance in grid system backup, relieving peak load power supply pressure, and peak and frequency regulation;

[0070] (2) The main operating mode of small and medium-sized energy storage cabinets used in industrial and commercial energy storage scenarios (banks, shopping malls, etc.) on the user side and small household energy storage boxes used in home energy storage scenarios on the user side is "peak shaving and valley filling". Since there is a large price difference in electricity charges at peak and valley locations according to electricity demand, after users have energy storage equipment, in order to reduce costs, they usually charge the energy storage cabinets / boxes during the low electricity price period; during the peak electricity price period, the electricity in the energy storage equipment is discharged for use to achieve the purpose of saving electricity bills. In addition, in remote areas and areas prone to natural disasters such as earthquakes and hurricanes, the existence of household energy storage devices is equivalent to users providing themselves and the power grid with backup power, eliminating the inconvenience caused by frequent power outages due to disasters or other reasons.

[0071] Take the household energy storage scenario in user-side energy storage as an example to illustrate. Figure 1 A household energy storage system is shown, which includes an energy storage device 1 and an electric energy conversion device 2 (such as a photovoltaic panel), and a user load 3 (such as a street lamp, household appliances, etc.). The energy storage device 1 is a small energy storage box that can be mounted on an outdoor wall by wall hanging. Specifically, the electric energy conversion device 2 can convert solar energy into electric energy during the period of low electricity prices, and store it through the energy storage device 1, and then supply the user load 3 for use during the peak electricity price, or supply the user load 3 for use when the power grid is out of power / power outage.

[0072] In combination with the above-mentioned situation of storing energy by physical or electrochemical means, taking electrochemical energy storage as an example, the energy storage device 1 includes at least one group of chemical batteries, using the chemical elements in the chemical batteries as energy storage media, so as to realize the charging and discharging process through the chemical reaction or change of the energy storage medium. In simple terms, the electric energy generated by light energy and wind energy is stored in at least one group of chemical batteries through the chemical reaction or change of the energy storage medium, and when the use of external electric energy reaches a peak, the electric energy stored in at least one group of chemical batteries is released for use through the chemical reaction or change of the energy storage medium, or transferred to a place where electric energy is scarce for use.

[0073] like Figure 2 As shown, the embodiment of the present application provides an energy storage device 1, which may be, but is not limited to, a battery pack, and an energy storage cabinet or energy storage container including the battery pack. Next, the energy storage device 1 is described as a battery pack.

[0074] like Figure 3 As shown, the battery pack includes a base 100, an upper cover 200, at least one battery module 300 and a cold plate 500. The upper cover 200 is connected to the base 100, and the upper cover 200 and the base 100 enclose a battery cavity 100a (such as Figure 5At least one battery module 300 is disposed in the battery cavity 100 a. A cold plate 500 is disposed on the bottom surface of the battery module 300 .

[0075] The shape of the base 100 and the upper cover 200 after being connected can have various embodiments, for example, it can be a hollow cube, a hollow rectangular parallelepiped, or other suitable shapes.

[0076] As an example, the base 100 is a rectangular parallelepiped with an opening, and the cold plate 500 and the battery module 300 are installed in the base 100 through the opening of the base 100. The upper cover 200 may be plate-shaped, and the upper cover 200 is buckled with the opening of the base 100 to form a battery cavity 100a.

[0077] In other embodiments, the base 100 and the upper cover 200 may both be in a rectangular shape and have an opening on one surface, the opening of the base 100 is arranged opposite to the opening of the upper cover 200, and the upper cover 200 and the base 100 are snapped together to form a battery cavity 100a for accommodating the battery module 300.

[0078] like Figure 3 As shown, the number of battery modules 300 can be one or more, and a plurality refers to more than two. The battery module 300 includes a plurality of single cells 310 arranged side by side. The single cells 310 can be lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-hydrogen batteries, nickel-cadmium batteries, lead-acid batteries, etc.

[0079] The single cell 310 has an explosion-proof valve hole 311. The single cell 310 also has an explosion-proof valve, which is arranged at the explosion-proof valve hole 311. When the single cell 310 has thermal runaway, the high-temperature and high-pressure gas generated inside the single cell 310 will break through the explosion-proof valve and then spray out from the explosion-proof valve hole 311.

[0080] For ease of explanation, the height direction of the single battery 310 is defined as the first direction D1, the length direction of the single battery 310 is defined as the second direction D2, and the width direction of the single battery 310 is defined as the third direction D3. The first direction D1, the second direction D2, and the third direction D3 are mutually perpendicular. When there are multiple battery modules 300, the multiple battery modules 300 are arranged side by side along the second direction D2. The multiple single batteries 310 of the battery module 300 are arranged side by side along the third direction D3.

[0081] like Figure 4 and Figure 5As shown, the upper cover 200 includes a first upper cover 210 and a second upper cover 220. The first upper cover 210 is connected to the base 100, and the first upper cover 210 and the base 100 enclose a battery cavity 100a. The second upper cover 220 is connected to the first upper cover 210, and the second upper cover 220 and the first upper cover 210 enclose a hollow cavity 230.

[0082] In one embodiment, the first upper cover 210 and the second upper cover 220 may be connected by welding, but the present invention is not limited thereto.

[0083] The first upper cover 210 has at least one ventilation structure 210a, and the ventilation structure 210a has a plurality of first through holes 211, and the first through holes 211 penetrate the inner wall surface and the outer wall surface of the first upper cover 210. Along the first direction D1, the positions of the plurality of explosion-proof valve holes 311 of the battery module 300 correspond to the positions of the plurality of first through holes 211 of the ventilation structure 210a.

[0084] For example, the number of the ventilation structure 210a may be one or more, and when the number of the ventilation structure 210a is plural, the plurality of ventilation structures 210a may be arranged at intervals along the second direction D2. The plurality of first through holes 211 of the ventilation structure 210a may be arranged along the third direction D3.

[0085] The inner wall surface of the first upper cover 210 refers to a side surface facing the battery cavity 100 a , and the outer wall surface of the first upper cover 210 refers to a side surface facing away from the battery cavity 100 a .

[0086] In the embodiment of the present application, the number of battery modules 300 is the same as the number of ventilation structures 210a, and the number of first through holes 211 included in the battery module 300 is the same as the number of first through holes 211 included in the ventilation structure 210a. For example, in one embodiment, the battery pack includes two battery modules 300, each battery module 300 includes four single cells 310, and each single cell 310 has an explosion-proof valve hole 311. The first upper cover 210 has two ventilation structures 210a, and each ventilation structure 210a has four first through holes 211. Along the first direction D1, the eight explosion-proof valve holes 311 correspond to the positions of the eight first through holes 211 respectively.

[0087] Of course, the number of battery modules 300 and the number of ventilation structures 210a are not limited to two, for example, the number of battery modules 300 and the number of ventilation structures 210a can both be one, three or other numbers. Similarly, the number of single batteries 310 included in the battery module 300 and the number of first through holes 211 included in the ventilation structure 210a are also not limited to four, for example, they can be two, three, five, six, eight or other numbers.

[0088] like Figure 2As shown, the second upper cover 220 has a second through hole 221, and the second through hole 221 passes through the inner wall surface and the outer wall surface of the second upper cover 220, and the second through hole 221 and the first through hole 211 are both connected to the hollow cavity 230. Among them, the inner wall surface of the second upper cover 220 refers to a side surface facing the hollow cavity 230, and the outer wall surface of the second upper cover 220 refers to a side surface facing away from the hollow cavity 230.

[0089] The battery pack further includes a box cover explosion-proof valve 240, which is connected to the second upper cover 220 and seals the second through hole 221. When the gas pressure in the hollow cavity 230 is greater than the explosion threshold of the box cover explosion-proof valve 240, the gas in the hollow cavity 230 can break through the box cover explosion-proof valve 240 and spray out through the second through hole 221.

[0090] In one embodiment, the box cover explosion-proof valve 240 can be connected to the second upper cover 220 by welding, but the present invention is not limited thereto.

[0091] like Figure 3 , Figure 5 and Figure 6 As shown, the battery pack also includes at least one gas guide structure 400, the gas guide structure 400 includes a plurality of gas guide components 400a, and the gas guide component 400a includes a valve 410 and a gas guide sleeve 420 made of a first shape memory alloy. The plurality of valves 410 of the gas guide structure 400 are respectively arranged at the openings of the plurality of first through holes 211 of the ventilation structure 210a. The gas guide sleeve 420 is located in the battery cavity 100a, and along the first direction D1, the positions of the plurality of gas guide sleeves 420 of the gas guide structure 400 correspond to the positions of the plurality of explosion-proof valve holes 311 of the battery module 300. One end of the gas guide sleeve 420 is connected to the first upper cover 210 or the valve 410, and is extended and arranged along the first direction D1.

[0092] The number of the gas guide structures 400 is the same as the number of the battery modules 300, and the number of the multiple gas guide components 400a included in the gas guide structure 400 is the same as the number of the multiple single batteries 310 included in the battery module 300. The number of the gas guide structures 400 can be one or more. When the number of the gas guide structures 400 is multiple, the multiple gas guide structures 400 are arranged side by side along the second direction D2. The multiple gas guide components 400a included in the gas guide structure 400 are arranged along the third direction D3.

[0093] For example, Figure 2 As shown, there are two air guide structures 400 , and each air guide structure 400 includes four air guide components 400 a , but the present invention is not limited thereto.

[0094] That is to say, in the embodiment of the present application, the number and position of the battery module 300, the ventilation structure 210a and the air guide structure 400 correspond, and the number and position of the multiple single batteries 310 included in a battery module 300, the multiple first through holes 211 included in a ventilation structure 210a, and the multiple air guide components 400a included in an air guide structure 400 correspond.

[0095] like Figure 5 and Figure 6 As shown, the valve 410 has a closed state in which the first through hole 211 is closed and an open state in which the first through hole 211 is opened. When the valve 410 is in the open state, the battery cavity 100a is connected to the hollow cavity 230 through the second through hole 221. The air guide sleeve 420 has a first state and a second state. When the air guide sleeve 420 is in the first state, the length of the air guide sleeve 420 is L1. When the air guide sleeve 420 is in the second state, the length of the air guide sleeve 420 is L2, and an air guide channel 423 is formed inside. The air guide channel 423 is respectively connected to the corresponding first through hole 211 and the corresponding explosion-proof valve hole 311, and L1<L2.

[0096] In one embodiment, the first shape memory alloy is a heat-elongation type, that is, when the temperature of the air guide sleeve 420 reaches the initial phase transition temperature of the first shape memory alloy, the air guide sleeve 420 automatically elongates. When the temperature of the air guide sleeve 420 returns to room temperature, the air guide sleeve 420 automatically shortens to its original state.

[0097] Of course, it is understandable that the first shape memory alloy is not limited to the heat-elongation type, for example, it can also be a type that bends or rotates after being heated, as long as the shape of the air guide sleeve 420 after being heated can play a role in guiding air.

[0098] Next, we will take the first shape memory alloy as an example of heat-expanding type. Figure 5 The four single cells 310 in the figure are defined as A1, A2, A3 and A4 from left to right. Among them, A2 has thermal runaway, while A1, A3 and A4 have not. After A2 has thermal runaway, the high-temperature and high-pressure gas generated inside A2 breaks through the explosion-proof valve of A2 and sprays out from the explosion-proof valve hole 311. According to the introduction in the background technology, the high-temperature and high-pressure gas sprayed from A2 will diffuse to other areas in the battery cavity 100a. The diffused high-temperature gas is reflected by the inner wall of the box and directly impacts the surface of the adjacent single cell 310 (for example, diffuses to A1 and A3, or even diffuses to A4 or diffuses to the single cell 310 of another battery module 300 arranged adjacent to the battery module 300), causing the temperature of the adjacent single cell 310 to rise sharply, increasing the risk of thermal runaway of the adjacent single cell 310.

[0099] In the embodiment of the present application, the gas guide assembly 400a includes a valve 410 and a gas guide sleeve 420. When the single battery 310 does not have thermal runaway, the valve 410 is in a closed state to close the first through hole 211, and the gas guide sleeve 420 is in a first state.

[0100] When A2 has thermal runaway, since the air guide sleeve 420 is made of the first shape memory alloy, after the air guide sleeve 420 corresponding to A2 is subjected to the high-temperature and high-pressure gas ejected from A2 and the temperature reaches the initial phase transition temperature of the first shape memory alloy, the air guide sleeve 420 switches from the first state to the second state, that is, the length of the air guide sleeve 420 is extended from L1 to L2. After the air guide sleeve 420 is extended, the air guide channel 423 formed inside it is respectively connected with the corresponding first through hole 211 and the explosion-proof valve hole 311, so that the high-temperature and high-pressure gas ejected from A2 can flow along the air guide channel 423, and try not to diffuse to the area where the adjacent single battery 310 is located. The high-temperature and high-pressure gas flowing into the air guide channel 423 can drive the valve 410 to switch from a closed state to an open state. When the valve 410 opens the first through hole 211, the gas can flow into the hollow cavity 230. When the gas pressure in the cavity 230 reaches the threshold of the box explosion-proof valve 240 , the gas breaks through the box explosion-proof valve 240 and is discharged from the battery pack.

[0101] It can be seen that the energy storage device 1 of the embodiment of the present application is provided with a valve 410 and a gas guide sleeve 420 made of the first shape memory alloy. When a single cell 310 in the energy storage device 1 has thermal runaway, the gas guide sleeve 420 corresponding to the single cell 310 can directly guide the high-temperature and high-pressure gas ejected from the single cell 310 out of the battery pack, and try to avoid the high-temperature and high-pressure gas from spreading to other areas in the battery cavity 100a, thereby avoiding the thermal runaway of other adjacent single cells 310 caused by the thermal runaway of a single cell 310, reducing the accumulation of pressure inside the battery cavity 100a and reducing the risk of explosion. In addition, since the gas guide sleeve 420 is made of the first shape memory alloy, it can automatically deform when subjected to high temperature to achieve the function of gas conduction, and can automatically return to its original state when the temperature returns to normal temperature, so the upper cover 200 and the gas guide component 400a can be reused, saving costs.

[0102] like Figure 6 As shown, when the air guide sleeve 420 is in the second state, the air guide sleeve 420 covers the opening edge of the explosion-proof valve hole 311 of the single battery 310. That is, when the air guide sleeve 420 is in the second state, one end of the air guide sleeve 420 away from the first through hole 211 contacts the opening edge of the explosion-proof valve hole 311 of the single battery 310.

[0103] In the embodiment of the present application, when thermal runaway occurs in the single cell 310, the gas guide sleeve 420 extends and covers the edge of the opening of the explosion-proof valve hole 311 of the single cell 310. The gas guide sleeve 420 seals the edge of the opening of the explosion-proof valve hole 311 to ensure that high-temperature and high-pressure gas can only flow into the gas guide channel 423 and will not diffuse outward.

[0104] Of course, in other embodiments, when the gas guide sleeve 420 is in the second state, there may be a small gap between the gas guide sleeve 420 and the single battery 310 , and the small gap does not affect the gas guide channel 423 from draining most of the high-temperature and high-pressure gas generated by the single battery 310 .

[0105] In one embodiment, the initial phase transition temperature of the first shape memory alloy is equal to the thermal runaway initial temperature of the battery cell 310 .

[0106] In the embodiment of the present application, the initial phase change temperature of the first shape memory alloy is set to be equal to the thermal runaway starting temperature of the single cell 310, so as to avoid the gas guide sleeve 420 from prematurely extending and blocking the explosion-proof valve hole 311 of the single cell 310, resulting in poor exhaust. Specifically, when the internal pressure of the single cell 310 increases and causes the explosion-proof valve to open, if the temperature of the gas ejected at this time has not reached the thermal runaway starting temperature of the single cell 310, the gas guide sleeve 420 remains in its original state and does not extend. At this time, there is enough exhaust space above the explosion-proof valve hole 311 of the single cell 310, so that the gas inside the single cell 310 can quickly diffuse to the area where the adjacent single cell 310 is located, and the speed of gas discharge from the inside of the single cell 310 and the speed of gas diffusion to the surrounding area are faster, thereby reducing the risk of explosion of the single cell 310. At the same time, since the temperature of the gas ejected from the single cell 310 is relatively low at this time, the temperature rise effect on the adjacent single cell 310 is also relatively small, and the adjacent single cell 310 will not be caused to have thermal runaway. It can be seen that setting the initial phase change temperature of the first shape memory alloy to be equal to the thermal runaway starting temperature of the single cell 310 not only ensures that the pressure relief speed of the single cell 310 in the early stage of valve opening is not affected, but also reduces the impact of high-temperature and high-pressure gas on the temperature rise of adjacent single cells 310.

[0107] It should be noted that the “starting phase change temperature” refers to the temperature at which the shape memory alloy begins to deform, and the “thermal runaway starting temperature” refers to the temperature threshold at which the single cell 310 begins to experience thermal runaway when experiencing external factors or internal failures.

[0108] It is understandable that the thermal runaway starting temperature of the single battery 310 is affected by various factors, such as battery type, internal chemical composition, use conditions and environment, etc.

[0109] In one embodiment, the first shape memory alloy may include any one of the following: nickel-titanium alloy, copper-aluminum-nickel alloy, copper-zinc-aluminum alloy, iron-cobalt alloy, and nickel-aluminum alloy (Ni—Al alloy).

[0110] The initial phase change temperature of the shape memory alloy can be controlled to be equal to the thermal runaway starting temperature of the single cell 310 by controlling the alloy composition and the heat treatment process, so that when the gas temperature reaches the thermal runaway starting temperature, the gas guide sleeve 420 can automatically extend, and when the temperature is lower than the thermal runaway starting temperature, the gas guide sleeve 420 can automatically shorten and return to its original state, ensuring that the gas guide sleeve 420 can be reused.

[0111] like Figure 7 As shown, the air guide sleeve 420 includes a sleeve 420a and a convex ring 420b, wherein the sleeve 420a is connected to the first upper cover 210 or the valve 410, and the convex ring 420b is convexly arranged on the outer peripheral side of the sleeve 420a. The side surface of the sleeve 420a facing the single battery 310 is a first surface 4221, and the side surface of the convex ring 420b facing the single battery 310 is a second surface 424. The first surface 4221 is flush with the second surface 424 and forms an annular covering surface 425; when the air guide sleeve 420 is in the second state, the annular covering surface 425 covers the opening edge of the explosion-proof valve hole 311 of the single battery 310.

[0112] In the embodiment of the present application, a convex ring 420b is provided at one end of the sleeve 420a away from the valve 410, and a first surface 4221 of the sleeve 420a and a second surface 424 of the convex ring 420b form an annular covering surface 425. When the air guide sleeve 420 is in the second state, the annular covering surface 425 covers the opening edge of the explosion-proof valve hole 311 of the single cell 310. The annular covering surface 425 increases the contact area between the air guide sleeve 420 and the single cell 310, further reducing the risk of the high-temperature and high-pressure gas ejected from the single cell 310 spreading outward from the gap between the air guide sleeve 420 and the single cell 310.

[0113] In one embodiment, the valve 410 is a one-way valve 410a, and the one-way valve 410a is configured to allow fluid to enter the hollow cavity 230 from the battery cavity 100a through the one-way valve 410a, while prohibiting the fluid from entering the battery cavity 100a through the one-way valve 410a from the hollow cavity 230.

[0114] In the embodiment of the present application, the arrangement of the one-way valve 410a ensures that the high-temperature gas ejected from the single cell 310 that has thermal runaway can only enter the hollow cavity 230 from the battery cavity 100a, and cannot flow back from the hollow cavity 230 to the battery cavity 100a, thereby preventing the gas from flowing back to the area where other single cells 310 are located in the battery cavity 100a, thereby preventing other single cells 310 from being affected by heat.

[0115] In one embodiment, the one-way valve 410a is threadedly connected to the second upper cover 220. In the embodiment of the present application, the one-way valve 410a is threadedly connected to the second upper cover 220, which facilitates the disassembly and assembly of the one-way valve 410a and the second upper cover 220 and facilitates subsequent maintenance.

[0116] like Figure 6 As shown, the one-way valve 410a includes a valve body 411, a blocking member 412, an elastic member 413 and a valve seat 414. The valve seat 414 can be connected to the second upper cover 220 by threads. For example, the second upper cover 220 has a threaded hole 222, the outer periphery of the valve seat 414 has an external thread, and the valve seat 414 is screwed into the threaded hole 222.

[0117] The valve body 411 is connected to the valve seat 414 and is inserted into the first through hole 211. The valve body 411 has a valve cavity 4111, and the inner wall of the valve cavity 4111 has a valve port 4112. The portion of the valve body 411 located between the first upper cover 210 and the second upper cover 220 also has an air outlet 4113, which is in communication with the hollow cavity 230 and the valve cavity 4111; the portion of the valve body 411 extending into the battery cavity 100a also has an air inlet 4114, which is in communication with the valve port 4112. The blocking member 412 is movably disposed in the valve cavity 4111, and is used to close or open the valve port 4112. The elastic member 413 is disposed in the valve cavity 4111, and is used to provide the blocking member 412 with an elastic force to close the valve port 4112.

[0118] like Figure 6 As shown, A2 has thermal runaway, and the high-temperature gas passes through the gas guide channel 423 of the gas guide sleeve 420 and enters the valve cavity 4111 through the air inlet 4114. Under the action of gas pressure, the blocking member 412 overcomes the elastic force provided by the elastic member 413 and moves upward, and then the blocking member 412 opens the valve port 4112, and the high-temperature gas passes through the valve port 4112 and flows into the hollow cavity 230 through the air outlet 4113.

[0119] A1 does not experience thermal runaway, and the sealing member 412 of the one-way valve 410a corresponding to A1 closes the valve port 4112 under the elastic force provided by the elastic member 413. At this time, the high-temperature gas ejected from A2 enters the hollow cavity 230 and does not flow back into the battery cavity 100a through the one-way valve 410a corresponding to A1.

[0120] In one embodiment, the valve body 411 is a cylindrical structure with openings at both ends. One end of the valve body 411 is connected to the valve seat 414, and the other end is connected to the air guide sleeve 420. As an example, the outer peripheral surface of the valve body 411 has an external thread, and the valve body 411 is screwed to the valve seat 414.

[0121] In one embodiment, the elastic member 413 may be a spring, one end of the elastic member 413 abuts against the valve seat 414, and the other end abuts against the blocking member 412. Of course, the elastic member 413 may also be other components capable of providing elastic force, such as rubber material.

[0122] like Figure 6 As shown, the air guide sleeve 420 is sleeved on the outer periphery of the portion of the valve body 411 extending into the battery cavity 100 a , and the air inlet 4114 is located in the air guide sleeve 420 .

[0123] For example, the air guide sleeve 420 and the valve body 411 may be connected by interference fit, threaded connection, riveting, etc., which is not particularly limited in the present application.

[0124] It can be understood that, in other embodiments, when the air guide sleeve 420 is in the second state, the positional relationship between the air guide sleeve 420 and the explosion-proof valve hole 311 of the single battery 310 can also be:

[0125] like Figure 8 As shown, the orthographic projection of the air guide sleeve 420 on a target plane is annular and is defined as a first projection S1. The orthographic projection of the explosion-proof valve hole 311 of the single battery 310 corresponding to the air guide sleeve 420 on the target plane is a second projection S2. The second projection S2 is located in the area enclosed by the inner circle of the first projection S1; wherein the target plane is perpendicular to the first direction D1.

[0126] In the embodiment of the present application, the second projection S2 is located in the area enclosed by the inner circle of the first projection S1. When the air guide sleeve 420 is in the second state, the air guide sleeve 420 can cover the explosion-proof valve hole 311 as a whole, so that the high-temperature gas can quickly enter the preset air guide channel 423, thereby preventing the high-temperature gas from diffusing to other areas of the battery cavity 100a.

[0127] like Fig. 9 As shown, the orthographic projection of the air guide sleeve 420 on a target plane is annular and is defined as the first projection S1. The orthographic projection of the first through hole 211 corresponding to the air guide sleeve 420 on the target plane is the third projection S3. The third projection S3 is located in the area enclosed by the inner circle of the first projection S1, or the boundary of the third projection S3 coincides with the inner circle of the first projection S1.

[0128] In the embodiment of the present application, the third projection S3 is located within the area enclosed by the inner circle of the first projection S1, or the boundary of the third projection S3 coincides with the inner circle of the first projection S1. When the air guide sleeve 420 is in the second state, the air guide sleeve 420 does not block the first through hole 211, and the high-temperature gas can pass through the first through hole 211 at a larger flow rate and enter the hollow cavity 230, thereby improving the pressure relief capacity of the air guide channel 423.

[0129] Combine the following Fig.10 and Fig.11 The flow of the high-temperature gas ejected when the single battery 310 experiences thermal runaway will be described in detail.

[0130] like Fig.10 As shown, none of the multiple single cells 310 has thermal runaway, at this time the valve 410 is in a closed state closing the first through hole 211, the air guide sleeve 420 is in the first state, and the box explosion-proof valve 240 is in a closed state.

[0131] like Fig.11 As shown, when one or more of the single cells 310 have thermal runaway, and the high-temperature gas ejected by the thermal runaway reaches the starting phase change temperature of the gas guide sleeve 420, the gas guide sleeve 420 is extended and covers the explosion-proof valve hole 311 of the single cell 310. The high-temperature gas ejected by the single cell 310 passes through the gas guide channel 423 of the gas guide sleeve 420, and switches the valve 410 to the open state of opening the first through hole 211, and the high-temperature gas enters the hollow cavity 230. When the gas pressure in the hollow cavity 230 reaches the explosion threshold of the box explosion-proof valve 240, the gas breaks through the box explosion-proof valve 240 and is discharged.

[0132] like Fig.12 and Fig.13 As shown, in another embodiment, the valve 410 can also be a phase change member 410b made of a second shape memory alloy, that is, the one-way valve 410a of the above embodiment is replaced by the phase change member 410b. The phase change member 410b is connected to the inner wall surface of the second upper cover 220, and the air guide sleeve 420 is connected to the inner wall surface of the first upper cover 210.

[0133] The length of the phase change element 410 b when in the closed state is L3 and closes the first through hole 211 ; the length of the phase change element 410 b when in the open state is L4 and opens the first through hole 211 , L3>L4.

[0134] In one embodiment, the phase change element 410 b may be in the shape of a long strip, and the cross-sectional shape may be in the shape of a circle, a rectangle, an ellipse, or the like.

[0135] When the phase change element 410 b is in the closed state, the end of the phase change element 410 b may contact the edge of the opening of the first through hole 211 , or the end of the phase change element 410 b may be inserted into the first through hole 211 .

[0136] In one embodiment, the second shape memory alloy is a heat-shrinkable type, that is, when the temperature of the phase change element 410b reaches the starting phase change temperature of the second shape memory alloy, the phase change element 410b automatically shrinks. When the temperature of the phase change element 410b returns to room temperature, the phase change element 410b automatically shrinks to its original state.

[0137] Of course, it is understandable that the second shape memory alloy is not limited to the type that shortens when heated. For example, it can also be the type that bends or rotates when heated, as long as the phase change element 410b can open the first through hole 211 after being heated and deformed, and close the first through hole 211 when at room temperature.

[0138] Next, the second shape memory alloy is taken as an example of a heat-shrinkable type. Fig.12 As shown, none of the multiple single cells 310 has thermal runaway, and at this time the phase change element 410b is in a closed state, with a length of L3, and closes the first through hole 211. In addition, the air guide sleeve 420 is in the first state. At the same time, the box explosion-proof valve 240 is also in a closed state.

[0139] like Fig.13 As shown, when one or more of the single cells 310 have thermal runaway, and the high-temperature gas ejected by the thermal runaway reaches the starting phase change temperature of the gas guide sleeve 420, the gas guide sleeve 420 stretches and covers the explosion-proof valve hole 311 of the single cell 310. The high-temperature gas ejected by the single cell 310 passes through the gas guide channel 423 of the gas guide sleeve 420, triggering the phase change element 410b, and the length of the phase change element 410b is shortened to L4. The phase change element 410b opens the first through hole 211, and the high-temperature gas enters the hollow cavity 230 through the first through hole 211. When the gas pressure in the hollow cavity 230 reaches the bursting threshold of the box explosion-proof valve 240, the gas breaks through the box explosion-proof valve 240 and is discharged.

[0140] It should be noted that, after the high-temperature gas enters the hollow cavity 230, the temperature of the gas has been relatively reduced, which is not enough to trigger the phase change components 410b corresponding to the remaining single cells 310 that have not experienced thermal runaway, so the remaining phase change components 410b are still in a closed state, that is, a state of closing the first through hole 211. Therefore, the remaining phase change components 410b can effectively prevent the high-temperature gas from flowing back into the battery cavity 100a from the remaining first through holes 211, and prevent the remaining single cells 310 from experiencing thermal runaway due to the influence of the refluxed high-temperature gas.

[0141] In one embodiment, the starting phase transition temperature of the second shape memory alloy is lower than the starting phase transition temperature of the first shape memory alloy.

[0142] In the embodiment of the present application, since the starting phase change temperature of the second shape memory alloy is lower than the starting phase change temperature of the first shape memory alloy, when thermal runaway occurs, the phase change element 410b will begin to shrink before the air guide sleeve 420. In this way, when the high-temperature gas enters the air guide channel 423 of the air guide sleeve 420, the phase change element 410b is already in an open state of opening the first through hole 211. At this time, the high-temperature gas can smoothly pass through the first through hole 211 and enter the hollow cavity 230, thereby avoiding the situation where the air guide sleeve 420 has been stretched while the phase change element 410b still remains in a state of closing the first through hole 211.

[0143] like Fig.14 As shown, in another embodiment of the energy storage device 1 of the present application, the upper cover 200 may not form the hollow cavity 230, but the upper cover 200 only includes the first upper cover 210, but not the second upper cover 220. The valve 410 is disposed at the first through hole 211 of the first upper cover 210, and is used to close or open the first through hole 211.

[0144] When thermal runaway occurs in one or more single cells 310 , the gas guide sleeve 420 corresponding to the single cell 310 extends, and the high-temperature gas passes through the gas guide channel 423 of the gas guide sleeve 420 and the valve 410 in sequence and is directly discharged from the box.

[0145] In one embodiment, the valve 410 may be a one-way valve 410a and configured to allow fluid to be discharged from the battery cavity 100a through the one-way valve 410a, while prohibiting fluid from entering the battery cavity 100a through the one-way valve 410a from outside the battery pack.

[0146] It should be noted that in the above embodiment, the number of the first through hole 211 of the ventilation structure 210a is not limited to multiple, for example, it can also be one. The number of the air guide components 400a of the air guide structure 400 is not limited to multiple, for example, it can also be one.

[0147] When the ventilation structure 210a has a first through hole 211, and the air guide structure 400 has an air guide component 400a, the valve 410 of the air guide component 400a is arranged at the opening of the first through hole 211, and in the first direction D1, the position of the air guide sleeve 420 of the air guide component 400a corresponds to the position of the explosion-proof valve hole 311 of one of the single cells 310 in the battery module 300. In this way, when one of the single cells 310 in the battery pack has thermal runaway, the air guide sleeve 420 can guide the high-temperature and high-pressure gas ejected from the single cell 310 out of the battery pack, and try to avoid the high-temperature and high-pressure gas from spreading to other areas in the battery cavity.

[0148] It should also be noted that the number of first through holes 211 included in a ventilation structure 210a is equal to the number of air guide components 400a included in an air guide structure 400, and the number of first through holes 211 included in a ventilation structure 210a can be less than or equal to the number of single cells 310 included in a battery module 300.

[0149] like Fig.15 As shown, the present application also provides an electrical device 4 , comprising any one of the energy storage devices 1 described above, and the energy storage device 1 supplies power to the electrical device 4 .

[0150] It is understandable that the various embodiments / implementations provided in the present application can be combined with each other without causing any contradiction, and will not be illustrated one by one here.

[0151] In the application embodiments, the terms "first", "second", and "third" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance; the term "plurality" refers to two or more, unless otherwise expressly defined. The terms "installed", "connected", "connected", "fixed", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; "connected" can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the application embodiments can be understood according to the specific circumstances.

[0152] In the description of the application embodiments, it should be understood that the directions or positional relationships indicated by the terms "up", "down", "left", "right", "front", "back", etc. are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the application embodiments and simplifying the description, rather than indicating or implying that the device or unit referred to must have a specific direction, be constructed and operated in a specific orientation, and therefore, should not be understood as a limitation on the application embodiments.

[0153] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "specific embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the application embodiment. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0154] The above are only preferred embodiments of the application embodiments and are not intended to limit the application embodiments. For those skilled in the art, the application embodiments may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the application embodiments shall be included in the protection scope of the application embodiments.

Claims

1. An energy storage device, characterized in that: include: Base; A first upper cover is connected to the base, and the first upper cover and the base form a battery cavity; The first upper cover has at least one ventilation structure, the ventilation structure has at least one first through hole, and the first through hole passes through the inner wall surface and the outer wall surface of the first upper cover; At least one battery module is disposed in the battery cavity and includes a plurality of single cells, each of which has an explosion-proof valve hole; along a first direction, the position of the explosion-proof valve hole of at least one of the single cells in the battery module corresponds to the position of at least one of the first through holes of the ventilation structure; the first direction is the height direction of the single cells; as well as At least one air guide structure, the air guide structure includes at least one air guide component, the air guide component includes a valve and an air guide sleeve made of a first shape memory alloy, the valve of at least one air guide component of the air guide structure is respectively arranged at the orifice of at least one first through hole of the ventilation structure, and the valve has a closed state of closing the first through hole and an open state of opening the first through hole; the air guide sleeve is located in the battery cavity, and along the first direction, the position of the air guide sleeve of at least one air guide component of the air guide structure corresponds to the position of the explosion-proof valve hole of at least one single battery of the battery module; one end of the air guide sleeve is connected to the first upper cover or the valve, and is extended along the first direction; the air guide sleeve has a first state and a second state, when the air guide sleeve is in the first state, the length of the air guide sleeve is L1, when the air guide sleeve is in the second state, the length of the air guide sleeve is L2, and an air guide channel is formed inside, and the air guide channel is respectively connected to the corresponding first through hole and the corresponding explosion-proof valve hole, L1<L2.

2. The energy storage device according to claim 1, characterized in that: When the air guide sleeve is in the second state, the air guide sleeve covers the opening edge of the explosion-proof valve hole of the single battery.

3. The energy storage device according to claim 1, characterized in that: The initial phase transition temperature of the first shape memory alloy is equal to the thermal runaway initial temperature of the single battery.

4. The energy storage device according to claim 1, characterized in that: The first shape memory alloy is a thermal elongation shape memory alloy.

5. The energy storage device according to claim 1, characterized in that: The air guide sleeve comprises a sleeve and a convex ring, wherein the sleeve is connected to the first upper cover or the valve, and the convex ring is convexly arranged on the outer peripheral side of the sleeve; The side surface of the sleeve facing the single cell is a first surface, the side surface of the convex ring facing the single cell is a second surface, the first surface is flush with the second surface and forms an annular covering surface; When the air guide sleeve is in the second state, the annular covering surface covers the opening edge of the explosion-proof valve hole of the single battery.

6. The energy storage device according to claim 1, characterized in that: The orthographic projection of the gas guide sleeve on a target plane is annular and is defined as a first projection. The orthographic projection of the explosion-proof valve hole of the single battery corresponding to the gas guide sleeve on the target plane is a second projection. The second projection is located in the area surrounded by the inner circle of the first projection. Wherein, the target plane is perpendicular to the first direction.

7. The energy storage device according to claim 1, characterized in that: The orthographic projection of the gas guide sleeve on a target plane is annular and is defined as a first projection. The orthographic projection of the first through hole corresponding to the gas guide sleeve on the target plane is a third projection. The third projection is located within the area enclosed by the inner circle of the first projection, or the boundary of the third projection coincides with the inner circle of the first projection. Wherein, the target plane is perpendicular to the first direction.

8. The energy storage device according to any one of claims 1 to 7, characterized in that: The energy storage device also includes: a second upper cover connected to the first upper cover, and the second upper cover and the first upper cover form a hollow cavity, the second upper cover has a second through hole, the second through hole and the first through hole are both connected to the hollow cavity; when the valve is in the open state, the battery cavity is connected to the hollow cavity through the second through hole; and The box cover explosion-proof valve is connected to the second upper cover and seals the second through hole.

9. The energy storage device according to claim 8, characterized in that: The valve is a one-way valve and is configured to allow fluid to enter the hollow cavity from the battery cavity through the one-way valve, while prohibiting fluid from entering the battery cavity from the hollow cavity through the one-way valve.

10. The energy storage device according to claim 9, characterized in that: The one-way valve comprises: A valve body is mounted on the second upper cover and penetrates the first through hole; the valve body has a valve cavity, the inner wall surface of the valve cavity has a valve port, the portion of the valve body located between the first upper cover and the second upper cover also has an air outlet, the air outlet is communicated with the hollow cavity and the valve cavity; the portion of the valve body extending into the battery cavity also has an air inlet, the air inlet is communicated with the valve port; A blocking member, movably disposed in the valve cavity, for closing or opening the valve port; An elastic member is disposed in the valve cavity and is used to provide an elastic force for closing the valve port to the blocking member.

11. The energy storage device according to claim 10, characterized in that: The air guide sleeve is sleeved on the outer periphery of the portion of the valve body extending into the battery cavity, and the air inlet is located in the air guide sleeve.

12. The energy storage device according to claim 8, characterized in that: The valve is a phase change member made of a second shape memory alloy, the phase change member is connected to the inner wall surface of the second upper cover, and the air guide sleeve is connected to the inner wall surface of the first upper cover; The length of the phase change element when in the closed state is L3 and closes the first through hole, and the length of the phase change element when in the open state is L4 and opens the first through hole, L3>L4.

13. The energy storage device according to claim 12, characterized in that: The starting phase transition temperature of the second shape memory alloy is lower than the starting phase transition temperature of the first shape memory alloy.

14. The energy storage device according to claim 12, characterized in that: The second shape memory alloy is a heat-shrinkable shape memory alloy.

15. An electrical equipment, characterized in that: The energy storage device comprises the energy storage device according to any one of claims 1 to 14, wherein the energy storage device supplies power to the electrical equipment.

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