Energy storage apparatus, energy storage module and electrical device

Abstract

Disclosed in the present application are an energy storage apparatus, an energy storage module and an electrical device. The energy storage apparatus comprises an end cover assembly, an electrode assembly, a partition member, a protection member and a housing, the partition member being provided with a through groove and through holes, the through groove and the through holes penetrating through the partition member in the thickness direction of the partition member, and the through groove and the through holes being arranged at intervals; the protection member is provided with a first containing cavity, the electrode assembly penetrates through the through groove, and the electrode assembly is in sealed connection with the groove wall of the through groove; the partition member is in sealed connection with the cavity wall of the first containing cavity and divides the first containing cavity into a first sub-containing cavity and a second sub-containing cavity, and the through holes communicate with the first sub-containing cavity and the second sub-containing cavity; the housing is provided with a second opening, the protection member is contained in the housing through the second opening, the end cover assembly is installed on the second opening and seals the second opening, and an electrolyte of the energy storage apparatus is contained in the housing and the first containing cavity; an air pressure difference can be generated between the first sub-containing cavity and the second sub-containing cavity, such that the electrolyte in the first sub-containing cavity flows to the second sub-containing cavity through the through holes.

Description

Energy storage devices, energy storage modules and electrical equipment

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on June 29, 2023, with application number 202310791439.X and application name “Energy Storage Device, Energy Storage Module and Electrical Equipment”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of energy storage technology, and in particular to an energy storage device, an energy storage module, and electrical equipment. Background Art

[0003] Due to the design requirements of energy storage devices, some require a horizontal position during operation. When placed horizontally, the electrode assemblies within the device are stacked. As the electrolyte within the device is consumed, the liquid level drops, preventing the upper electrode assemblies from being soaked in electrolyte, thus affecting the device's performance.

[0004] Summary of the Invention

[0005] The present application provides an energy storage device, an energy storage module and an electrical device, which are used to solve the problem in the prior art that when the energy storage device is placed flat, the upper electrode assembly cannot be soaked in the electrolyte.

[0006] In the first aspect, the present application provides an energy storage device, including an end cap assembly, an electrode assembly, a partition, a protective member and a shell, wherein the partition is provided with a through groove and a through hole, the through groove and the through hole both pass through the partition along the thickness direction of the partition, and the through groove and the through hole are arranged at intervals; the protective member is provided with a first accommodating cavity, the first accommodating cavity has a first opening, the partition and the electrode assembly are both accommodated in the first accommodating cavity, the electrode assembly passes through the through groove, and the electrode assembly is sealed with the groove wall of the through groove; the partition is sealed with the cavity wall of the first accommodating cavity, and the first accommodating cavity is divided into a first sub-accommodating cavity The first sub-holding chamber is connected to the first opening, and the through hole is connected to the first sub-holding chamber and the second sub-holding chamber; the electrode assembly, the partition member and the protective member are all accommodated in the shell, the end cover assembly is installed at one end of the shell, the end cover assembly seals the shell, the end cover assembly is opposite to the first opening and connected to the protective member, the electrolyte of the energy storage device is accommodated in the shell and the first holding chamber; an air pressure difference can be generated between the first sub-holding chamber and the second sub-holding chamber, so that the electrolyte in the first sub-holding chamber flows to the second sub-holding chamber through the through hole.

[0007] In a second aspect, the present application provides an energy storage module, comprising a plurality of energy storage devices, wherein the plurality of energy storage devices are electrically connected.

[0008] In a third aspect, the present application provides an electrical device, comprising an energy storage module, wherein the energy storage module is used to supply power to the electrical device.

[0009] To summarize, the embodiment of the present application forms a first sub-holding chamber and a second sub-holding chamber of different sizes by setting a partition. The air pressure difference between the first sub-holding chamber and the second sub-holding chamber forms a liquid level difference of the electrolyte between the two cavities. The smaller second sub-holding chamber can maintain a higher liquid level to achieve continuous infiltration and replenishment of the second electrode assembly. Even if the electrolyte level drops, it will not affect the infiltration of the electrolyte on the side of the winding core away from the bottom surface, thereby significantly improving the service life of the energy storage device. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings required for use in the implementation. Obviously, the drawings described below are only some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained like these drawings without any creative work.

[0011] FIG1 is an application scenario diagram of a household energy storage system provided in an embodiment of the present application;

[0012] FIG2 is a schematic structural diagram of an energy storage device provided in an embodiment of the present application;

[0013] FIG3 is an exploded view of the structure of the energy storage device shown in FIG2 ;

[0014] FIG4 is a schematic structural diagram of the electrode assembly shown in FIG3 ;

[0015] FIG5 is a schematic structural diagram of the partition member shown in FIG3 ;

[0016] FIG6 is a schematic structural diagram of the protective member shown in FIG3 ;

[0017] FIG7 is a schematic diagram of the structure in which the partition member is fixedly connected to the protective member;

[0018] FIG8 is a schematic structural diagram of the housing shown in FIG3 ;

[0019] FIG9 is a partial structural perspective view of the energy storage device shown in FIG2 .

[0020] Reference numerals: household energy storage system 1000; energy storage device 100; electric energy conversion device 200; user load 300; end cap assembly 10; electrode assembly 20; partition member 30; protective member 40; housing 50; positive electrode post 11; negative electrode post 12; explosion-proof valve 13; main body 21; positive electrode tab 22; negative electrode tab 23; first end 24; second end 25; side portion 27; first electrode assembly 20A; second electrode assembly 20B; recess 26; first recess 26A; second recess 26B; bottom plate 31; top plate 32; Side panel 33; through groove 37; first sub-side panel 33A; second sub-side panel 33B; through hole 34; first protrusion 35; first contact surface 351; second contact surface 352; second protrusion 36; third contact surface 361; fourth contact surface 362; first accommodating chamber 41; first opening 42; bottom wall 43; top wall 44; first side wall 46; second side wall 45; first sub-side wall 45A; second sub-side wall 45B; second accommodating chamber 51; second opening 52; support plate 60; first sub-accommodating chamber 41A; second sub-accommodating chamber 41B. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0022] Because the energy we need is highly temporal and spatially dependent, rationally utilizing and improving energy efficiency requires a medium or device that can store one form of energy in the same form or convert it into another, allowing it to be released in a specific form based on future application needs. As we all know, achieving the goal of carbon neutrality currently relies primarily on developing green energy sources such as photovoltaics and wind power to replace fossil fuels.

[0023] Currently, the generation of green electricity generally relies on photovoltaics, wind power, and hydropower. However, wind and solar energy are generally intermittent and highly volatile, which can cause grid instability, insufficient electricity during peak hours, and excessive electricity during off-peak hours. Unstable voltage can also damage electricity. Therefore, insufficient electricity demand or insufficient grid capacity may lead to the problem of "wind and solar power curtailment". To solve these problems, we must rely on energy storage. That is, electrical energy is converted into other forms of energy through physical or chemical means and stored, and then converted into electrical energy and released when needed. Simply put, energy storage is like a large "power bank". When there is sufficient photovoltaic and wind energy, it stores electrical energy and releases the stored electricity when needed.

[0024] Please refer to FIG1 , which is an application scenario diagram of a household energy storage system 1000 provided in an embodiment of the present application.

[0025] Taking the household energy storage scenario in user-side energy storage as an example, Figure 1 shows a household energy storage system. The household energy storage system includes an energy storage device 100, an electric energy conversion device 200 (such as a photovoltaic panel), and a user load 300 (such as a street lamp, household appliances, etc.). The energy storage device 100 is a small energy storage box that can be mounted on an outdoor wall. Specifically, the electric energy conversion device 200 can convert solar energy into electrical energy during periods of low electricity prices and store it in the energy storage device 100. The energy can then be supplied to the user load 300 for use during peak electricity prices or during power outages.

[0026] In conjunction with the aforementioned physical or electrochemical energy storage, taking electrochemical energy storage as an example, the energy storage device 100 includes at least one set of chemical batteries, utilizing the chemical elements within the chemical batteries as the energy storage medium, with the charging and discharging process achieved through chemical reactions or changes in the energy storage medium. Simply put, the electrical energy generated by solar energy or wind energy is stored in the at least one set of chemical batteries through chemical reactions or changes in the energy storage medium. When external electrical energy usage reaches a peak, the energy stored in the at least one set of chemical batteries is released through chemical reactions or changes in the energy storage medium for use, or transferred to areas with power shortages for use.

[0027] Please refer to FIG. 2 , which is a schematic structural diagram of an energy storage device 100 provided in an embodiment of the present application.

[0028] The present application provides an energy storage device 100, an energy storage module (not shown) including a plurality of energy storage devices 100, and an electrical device (not shown) using the energy storage module. In this embodiment, the energy storage device 100 is described by taking a battery as an example. When the energy storage device 100 is a single cell, it may be a square battery. The energy storage module may include but is not limited to a battery module, a battery pack, a battery system, etc. Electrical devices may include but are not limited to large energy storage containers used in grid-side energy storage scenarios, 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.

[0029] For the convenience of description, the length direction of the energy storage device 100 shown in Figure 2 is defined as the X-axis direction, the width direction of the energy storage device 100 is defined as the Y-axis direction, and the thickness direction of the energy storage device 100 is defined as the Z-axis direction. The X-axis direction, the Y-axis direction, and the Z-axis direction are perpendicular to each other. It should be noted that the same as described in this application is that a certain range of tolerances is allowed. The directional terms such as "up", "down", "inside", and "outside" mentioned in the description of the embodiments of this application are described based on the directions shown in Figure 2 of the specification, with the direction facing the positive direction of the Z-axis being "up", the direction facing the negative direction of the Z-axis being "down", the direction facing the inside of the energy storage device 100 being "inside", and the direction facing the outside of the energy storage device 100 being "outside". It does not constitute a limitation on the energy storage device 100 in actual application scenarios.

[0030] Please also refer to FIG. 3 , which is an exploded view of the energy storage device 100 shown in FIG. 2 .

[0031] The energy storage device 100 includes an end cap assembly 10, an electrode assembly 20, a partition 30, a protective member 40, and a housing 50. One end of the electrode assembly 20 is connected to the end cap assembly 10, and the partition 30 is fixedly connected to the protective member 40. The protective member 40 and the partition 30 are both sleeved around the periphery of the electrode assembly 20. The electrode assembly 20, the partition 30, and the protective member 40 are all housed in the housing 50. The end cap assembly 10 is mounted on one end of the housing 50 and seals the housing 50.

[0032] As shown in Figure 2, the end cover assembly 10 includes a positive electrode column 11, a negative electrode column 12 and an explosion-proof valve 13. In this embodiment, along the length direction of the end cover assembly 10 (Y-axis direction), the positive electrode column 11 and the negative electrode column 12 are respectively located at opposite ends of the end cover assembly 10 and are spaced apart. The positive electrode column 11 and the negative electrode column 12 are both made of metal materials. The positive electrode column 11 is used as the positive terminal when the energy storage device 100 is connected to other equipment, and the negative electrode column 12 is used as the negative terminal when the energy storage device 100 is connected to other equipment. The explosion-proof valve 13 is located between the positive electrode column 11 and the negative electrode column 12, and is spaced apart from the positive electrode column 11 and the negative electrode column 12. When the pressure inside the energy storage device 100 is too high, the explosion-proof valve 13 can automatically open and release the pressure to prevent the energy storage device 100 from exploding.

[0033] Please also refer to FIG. 4 , which is a schematic structural diagram of the electrode assembly 20 shown in FIG. 3 .

[0034] The electrode assembly 20 is generally plate-shaped and is used to undergo an electrochemical reaction with the electrolyte to store or release electrical energy. The electrode assembly 20 includes a main body 21, a positive electrode tab 22, and a negative electrode tab 23. The electrode assembly 20 is formed by winding a positive electrode sheet and a negative electrode sheet, and a separator is usually provided between the positive electrode sheet and the negative electrode sheet. The portion of the positive electrode sheet and the negative electrode sheet containing active material constitutes the main body 21 of the electrode assembly 20. The remaining portion of the positive electrode sheet constitutes the positive electrode tab 22, and the remaining portion of the negative electrode sheet constitutes the negative electrode tab 23. The main body 21 includes a first end 24, a second end 25, and two side portions 27. The first end 24 and the second end 25 are arranged opposite to each other along the length direction (X-axis direction) of the main body 21. The two side portions 27 are connected between the first end 24 and the second end 25, and the two side portions 27 are arranged opposite to each other along the width direction (Y-axis direction) of the main body 21. In this embodiment, both side portions are semi-cylindrical, and each side portion protrudes away from the other side portion. In the embodiment of the present application, the positive electrode tab 22 and the negative electrode tab 23 are both provided at the first end 24 of the main body 21, and the positive electrode tab 22 and the negative electrode tab 23 are opposite and spaced apart along the width direction (Y-axis direction) of the main body 21. In other embodiments, the positive electrode tab 22 and the negative electrode tab 23 can also be provided at the first end 24 and the second end 25 of the main body 21, respectively. The electrode assembly 20 is connected to the end cap assembly 10. The first end 24 faces the end cap assembly 10, and the second end 25 faces away from the end cap assembly 10. The positive electrode tab 22 is welded to the positive electrode post 11 and can be electrically conductive; the negative electrode tab 23 is welded to the negative electrode post 12 and can be electrically conductive.

[0035] As shown in FIG3 , in this embodiment, there are two electrode assemblies 20 , namely a first electrode assembly 20A and a second electrode assembly 20B. The first electrode assembly 20A and the second electrode assembly 20B are stacked along the thickness direction (Z-axis direction) of the electrode assembly 20. Two recesses 26 are formed between the side portion 27 of the first electrode assembly 20A and the side portion 27 of the second electrode assembly 20B. The recesses 26 extend along the length direction (X-axis direction) of the electrode assembly 20. The two recesses 26 are respectively a first recess 26A and a second recess 26B. The first recess 26A and the second recess 26B are arranged opposite each other along the width direction (Y-axis direction) of the electrode assembly 20. The notch of the first recess 26A faces away from the second recess 26B, and the opening of the second recess 26B faces away from the first recess 26A.

[0036] In other embodiments, the number of electrode assemblies 20 may be one or greater than two, and the specific number is not limited. When the number of electrode assemblies 20 is greater than two, the plurality of electrode assemblies 20 are stacked along the thickness direction of the electrode assembly 20. A plurality of first recesses 26A and a plurality of second recesses 26B are formed between the plurality of electrode assemblies 20. The plurality of first recesses 26A are spaced apart along the thickness direction of the electrode assembly 20, and the plurality of second recesses 26B are spaced apart along the thickness direction of the electrode assembly 20. The first recesses 26A and the second recesses 26B are disposed opposite each other along the width direction of the electrode assembly 20.

[0037] Please refer to FIG. 5 , which is a schematic structural diagram of the partition member 30 shown in FIG. 3 .

[0038] The partition member 30 is a generally rectangular frame, which is sleeved around the periphery of the electrode assembly 20 and has an interference fit with the electrode assembly 20. The partition member 30 is made of an elastic insulating material. In this embodiment, the partition member 30 is made of polypropylene (PP).

[0039] The partition member 30 includes a bottom plate 31, a top plate 32 and two side plates 33. The top plate 32 and the bottom plate 31 are arranged relative to each other along the height direction (Z-axis direction) of the partition member 30, and the two side plates 33 are arranged relative to each other along the length direction (Y-axis direction) of the partition member 30, and are both connected between the top plate 32 and the bottom plate 31 to form a through groove 37. The connection between the inner wall surface of the two side plates 33 and the inner wall surface of the top plate 32 is in the shape of a circular arc, and the connection between the inner wall surface of the two side plates 33 and the inner wall surface of the bottom plate 31 is in the shape of a circular arc. It can be understood that the inner wall surfaces at the four corner connections of the partition member 30 are all circular arc surfaces to fit closely with the outer peripheral surface of the electrode assembly 20. The two side plates 33 are respectively the first sub-side plate 33A and the second sub-side plate 33B.

[0040] The partition piece 30 is provided with a through hole 34. The through hole 34 is provided on the side plate 33 and passes through the side plate 33 along the thickness direction (X-axis direction) of the partition piece 30. In this embodiment, the through hole 34 is a circular hole. In other embodiments, the shape of the through hole 34 can also be rectangular, triangular or rhombus, etc., and the specific shape is not limited. The ratio of the height h1 of the through hole 34 to the height h2 of the partition piece 30 is 0.05-0.1, and the ratio of the aperture d of the through hole 34 to the height h2 of the partition piece 30 is 0.03-0.05. Specifically, the height h1 of the through hole 34 refers to the distance between the geometric center of the through hole 34, that is, the center of the circle in this embodiment, and the outer wall surface of the bottom plate 31; the aperture d of the through hole 34 refers to the hole diameter when the through hole 34 is a circular hole; the height h2 of the partition piece 30 refers to the distance between the outer wall surface of the top plate 32 and the outer wall surface of the bottom plate 31. In this embodiment, the number of through-holes 34 is two, with two through-holes 34 disposed on each side plate 33 and arranged opposite each other along the length of the partition member 30 to ensure more uniform electrolyte flow. In other embodiments, the through-holes 34 include two groups of sub-through-holes, each of which is disposed on each side plate 33 and opposite each other along the length of the partition member 30.

[0041] In one embodiment, the barrier member 30 is further provided with a one-way valve. The one-way valve can be disposed on the wall of the through hole 34 or on one surface of the barrier member 30 along the thickness direction. Along the thickness direction of the barrier member 30, the orthographic projection of the one-way valve completely covers the orthographic projection of the through hole 34. The one-way valve is used to ensure unidirectional flow of fluid.

[0042] The partition member 30 is also provided with a first protrusion 35 and a second protrusion 36. The first protrusion 35 and the second protrusion 36 both face the through-slot 37 and are arranged opposite each other along the length of the partition member 30. The first protrusion 35 is provided on the inner wall surface of the first sub-side plate 33A. The first protrusion 35 includes a first contact surface 351 and a second contact surface 352 arranged opposite to the first contact surface 351. The first contact surface 351 and the second contact surface 352 are both arc-shaped surfaces. One side of the first contact surface 351 is connected to the first sub-side plate 33A, the other side of the first contact surface 351 is connected to one side of the second contact surface 352, and the other side of the second contact surface 352 is connected to the first sub-side plate 33A. The first protrusion 35 is inserted into the first recess 26A. The first contact surface 351 and the second contact surface 352 respectively mate with the two opposing inner wall surfaces of the first recess 26A. The second protrusion 36 is provided protrudingly on the inner wall surface of the second sub-side plate 33B. The second protrusion 36 includes a third contact surface 361 and a fourth contact surface 362 disposed opposite to the third contact surface 361. Both the third contact surface 361 and the fourth contact surface 362 are arcuate surfaces. One side of the third contact surface 361 is connected to the second sub-side plate 33B, and the other side of the third contact surface 361 is connected to one side of the fourth contact surface 362. The other side of the fourth contact surface 362 is connected to the second sub-side plate 33B. The second protrusion 36 is inserted into the second recess 26B. The third contact surface 361 and the fourth contact surface 362 respectively mate with two opposing inner wall surfaces of the second recess 26B.

[0043] In this embodiment, the number of the first protrusion 35 and the second protrusion 36 is one, and the first protrusion 35 and the second protrusion 36 are integrally formed with the partition member 30 to simplify the process and reduce processing costs. In other embodiments, there can be multiple first protrusions 35 and the second protrusion 36, and the number of the first protrusion 35 and the second protrusion 36 is the same. Along the length direction of the partition member 30, a first protrusion 35 and a second protrusion 36 are arranged opposite to each other. Along the width direction of the partition member 30, multiple first protrusions 35 are arranged at intervals, and multiple second protrusions 36 are arranged at intervals. Each first protrusion 35 is inserted into a first recess 26A, and each second protrusion 36 is inserted into a second recess 26B to tightly press the outer surface of the electrode assembly 20 to achieve an interference fit between the partition member 30 and the electrode assembly 20.

[0044] In one embodiment, the first protrusion 35 and the second protrusion 36 both have a pointed portion, i.e., a sharp angle is formed at the junction of the first contact surface 351 and the second contact surface 352. When the partition member 30 is sleeved around the periphery of the electrode assembly 20, the pointed portion is inserted into the recess 26 and closes the gap between the electrode assemblies 20, thereby achieving a better seal between the partition member 30 and the electrode assembly 20.

[0045] Please refer to FIG. 6 , which is a schematic structural diagram of the protection member 40 shown in FIG. 3 .

[0046] The protective member 40 is a generally rectangular hollow body made of an insulating material. The protective member 40 is sleeved on the outer surface of the electrode assembly 20 and connected to the end cap assembly 10. The protective member 40 is used to protect the electrode assembly 20, preventing the electrode assembly 20 from being scratched by the housing 50 during placement into the housing 50, and insulating the electrode assembly 20 from the housing 50. In this embodiment, the protective member 40 is mylar, a polyester film. The protective member 40 can be bonded to the side of the end cap assembly 10 facing the electrode assembly 20 by a hot melt process.

[0047] The protective member 40 has a first accommodating cavity 41 and a first opening 42. The first opening 42 and the first accommodating cavity 41 are interconnected along the length (X-axis) of the protective member 40. The first accommodating cavity 41 is used to accommodate the electrode assembly 20 and the partition member 30. When the protective member 40 is mounted on the electrode assembly 20, the electrode assembly 20 enters the first accommodating cavity 41 through the first opening 42.

[0048] The protective member 40 includes a bottom wall 43, a top wall 44, a first side wall 46 and two second side walls 45. The top wall 44 and the bottom wall 43 are arranged opposite to each other along the height direction (Z-axis direction) of the protective member 40. The two second side walls 45 are arranged opposite to each other along the width direction (Y-axis direction) of the protective member 40, and are both connected between the top wall 44 and the bottom wall 43. The first side wall 46 is arranged at one end of the length direction (X-axis direction) of the protective member 40, and is connected between the top wall 44 and the bottom wall 43, and is connected between the two second side walls 45. The bottom wall 43, the top wall 44, the two second side walls 45 and the first side wall 46 are connected to form a first accommodating cavity 41, and the first opening 42 is located at one end of the length direction of the protective member 40, and is arranged opposite to the first side wall 46. The two second side walls 45 are respectively the first sub-side wall 45A and the second sub-side wall 45B.

[0049] Please refer to FIG. 5 to FIG. 7 . FIG. 7 is a schematic structural diagram of the partition member 30 fixedly connected to the protective member 40 .

[0050] The partition member 30 is fixedly connected to the first accommodating chamber 41 of the protective member 40. The bottom plate 31 is connected and fixed to the bottom wall 43, the top plate 32 is connected and fixed to the top wall 44, the first sub-side plate 33A is connected and fixed to the first sub-side wall 45A, and the second sub-side plate 33B is connected and fixed to the second sub-side wall 45B. The partition member 30 divides the first accommodating chamber 41 into a first sub-accommodating chamber 41A and a second sub-accommodating chamber 41B. In the longitudinal direction of the protective member 40, the first opening 42, the first sub-accommodating chamber 41A and the second sub-accommodating chamber 41B are connected, and the through groove 37 is connected between the first sub-accommodating chamber 41A and the second sub-accommodating chamber 41B. The ratio of the distance L1 between the partition member 30 and the first side wall 46 to the length L2 of the protective member 40 is 0.1-0.15. L1 refers to the distance between the surface of the partition member 30 facing the first side wall 46 and the outer surface of the first side wall 46; L2 refers to the length (X-axis) dimension of the second side wall 45. It is understood that the volume of the first sub-accommodation chamber 41A is much larger than the volume of the second sub-accommodation chamber 41B. The partition member 30 can be bonded to the protective member 40, fixedly connected to the protective member 40 via a hot melt process, or integrally formed with the protective member 40.

[0051] Please refer to FIG. 8 , which is a schematic structural diagram of the housing 50 shown in FIG. 3 .

[0052] The housing 50 is generally rectangular and made of metal. It defines a second accommodating cavity 51 and a second opening 52. The second opening 52 and the second accommodating cavity 51 extend through the length of the housing 50. The electrode assembly 20 and the protective member 40 are accommodated in the second accommodating cavity 51 through the second opening 52. The end cap assembly 10 is mounted in the second opening 52 and seals the housing 50.

[0053] Continuing with FIG3 , in this embodiment, the energy storage device 100 further includes a support plate 60 for supporting the electrode assembly 20. The support plate 60 is generally rectangular and made of an insulating material. The support plate 60 is housed within the second accommodating cavity 51 of the housing 50 and disposed between the first side wall 46 of the protective member 40 and the housing 50, where it is fixedly connected to the first side wall 46. In some embodiments, the support plate 60 may be integrally formed with the protective member 40.

[0054] Please refer to FIG. 9 , which is a partial structural perspective view of the energy storage device 100 shown in FIG. 2 .

[0055] After the energy storage device 100 is assembled, electrolyte is injected into the protective member 40 through the injection hole on the end cap assembly 10. The electrolyte is stored in the first accommodating cavity 41 and soaks the electrode assembly 20. In this embodiment, the energy storage device 100 is in a flat position during operation, with the first electrode assembly 20A and the second electrode assembly 20B stacked perpendicular to the ground, with the second electrode assembly 20B located on the side facing away from the ground.

[0056] In the working state, the electrolyte in the energy storage device 100 reacts with the electrode assembly 20 and is continuously consumed, and its liquid level continues to drop. In addition, gas is generated when the electrolyte in the energy storage device 100 reacts with the electrode assembly 20. Because the partition 30 divides the first housing chamber 41 into the first sub-housing chamber 41A and the second sub-housing chamber 41B, and the volume of the first sub-housing chamber 41A is much larger than the volume of the second sub-housing chamber 41B, most of the electrode assembly 20 is located in the first sub-housing chamber 41A, and the gas generated by the reaction between the electrode assembly 20 and the electrolyte is also concentrated in the first sub-housing chamber 41A. The large amount of gas retained in the first sub-housing chamber 41A will squeeze the electrolyte, causing the electrolyte to flow from the first sub-housing chamber 41A to the second sub-housing chamber 41B through the through-hole 34 provided on the partition 30, thereby raising the liquid level in the second sub-housing chamber 41B. As the energy storage device 100 continues to operate, electrolyte is continuously consumed and gas is generated. The pressure difference between the first sub-chamber 41A and the second sub-chamber 41B gradually increases, and the electrolyte level difference between the second sub-chamber 41B and the first sub-chamber 41A also gradually increases. Therefore, when the electrolyte level in the first sub-chamber 41A is lower than the surface of the second electrode assembly 20B facing the ground, the electrolyte level in the second sub-chamber 41B remains higher than the surface of the second electrode assembly 20B facing the ground. Therefore, the electrolyte in the second sub-chamber 41B can continuously contact the second end 25 of the second electrode assembly 20B and is attracted by the diaphragm of the second electrode assembly 20B through capillary action and transported to the entire second electrode assembly 20B, thereby achieving electrolyte circulation and simultaneously soaking multiple electrode assemblies 20.

[0057] In this embodiment, since both the first protrusion 35 and the second protrusion 36 of the partition member 30 have pointed portions, after the electrode assembly 20 passes through the through-slot 37, the pointed portions are inserted into the recess 26 to fill the gap between the electrode assemblies, thereby ensuring a better seal between the partition member 30 and the electrode assembly 20, preventing the gas generated in the first sub-accommodating chamber 41A from flowing into the second sub-accommodating chamber 41B through the gap between the partition member 30 and the electrode assembly 20, thereby reducing the pressure difference between the first sub-accommodating chamber 41A and the second sub-accommodating chamber 41B, and affecting the effect of the electrolyte circulating and infiltrating the multiple electrode assemblies 20.

[0058] In one embodiment, the number of electrode assemblies 20 is one. When the energy storage device 100 is in a lying state, the electrode assembly 20 is arranged perpendicular to the ground. When the electrolyte in the energy storage device 100 reacts with the electrode assembly 20 and is continuously consumed, and the electrolyte level continues to drop, the portion of the electrode assembly 20 away from the ground will not be wetted by the electrolyte, affecting the service life of the energy storage device 100. A first sub-chamber 41A and a second sub-chamber 41B are formed by providing a partition 30, and the air pressure difference between the first sub-chamber 41A and the second sub-chamber 41B is utilized to maintain a higher liquid level in the second sub-chamber 41B to achieve continuous wetting and fluid replenishment of the portion of the electrode assembly 20 away from the ground.

[0059] In one embodiment, the partition member 30 is further provided with a one-way valve. The orthographic projection of the one-way valve completely covers the orthographic projection of the through-hole 34 along the thickness direction of the partition member 30. The one-way valve allows the electrolyte to flow only from the first sub-cavity 41A to the second sub-cavity 41B, but not in the opposite direction. This helps maintain the liquid level difference between the first sub-cavity 41A and the second sub-cavity 41B, thereby achieving electrolyte circulation and simultaneously soaking the multiple electrode assemblies 20.

[0060] To summarize, the embodiment of the present application forms a first sub-chamber 41A and a second sub-chamber 41B of different sizes by setting a partition 30. The air pressure difference between the first sub-chamber 41A and the second sub-chamber 41B forms a liquid level difference of the electrolyte between the two cavities. The smaller second sub-chamber 41B can maintain a higher liquid level to achieve continuous infiltration and replenishment of the second electrode assembly 20B. Even if the electrolyte level drops, it will not affect the infiltration of the electrolyte on the electrode assembly 20 on the side away from the ground, thereby significantly improving the service life of the energy storage device 100.

[0061] As shown in FIG5 , in the embodiment of the present application, the ratio of the height h1 of the through-hole 34 to the height h2 of the partition member 30 should be less than or equal to 0.1 to prevent the through-hole 34 from being set too high. This is because when the electrolyte level drops to the height of the through-hole 34, gas will also flow through the through-hole 34, and the gas pressure difference and electrolyte level difference between the first sub-cavity 41A and the second sub-cavity 41B will not be maintained, thus preventing continuous wetting of the second electrode assembly 20B. The ratio of the height h1 of the through-hole 34 to the height h2 of the partition member 30 should be greater than or equal to 0.05 to prevent the through-hole 34 from being set too low, close to the edge of the partition member 30, resulting in insufficient structural strength of the partition member 30 at the through-hole 34.

[0062] In the embodiment of the present application, the ratio of the aperture d of the through hole 34 to the height h2 of the partition member 30 should be greater than or equal to 0.03 to avoid the through hole 34 being too small and hindering the flow of electrolyte between the first sub-holding chamber 41A and the second sub-holding chamber 41B; the ratio of the aperture d of the through hole 34 to the height h2 of the partition member 30 should be less than or equal to 0.05 to avoid the through hole 34 being too large and the structural strength of the partition member 30 at the through hole 34 being insufficient.

[0063] As shown in Figure 7, in the embodiment of the present application, the ratio of the distance L1 between the partition member 30 and the first side wall 46 to the length L2 of the protective member 40 should be greater than or equal to 0.1, so as to avoid the second sub-holding chamber 41B being too small and unable to store a sufficient amount of electrolyte to infiltrate the second battery cell; the ratio of the distance L1 between the partition member 30 and the first side wall 46 to the length L2 of the protective member 40 should be less than or equal to 0.15, so as to avoid the second sub-holding chamber 41B being too large and the first sub-holding chamber 41A being too small, so as to avoid forming a sufficient air pressure difference and electrolyte liquid level difference between the first sub-holding chamber 41A and the second sub-holding chamber 41B.

[0064] The above is a detailed introduction to the embodiments of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core idea of ​​the present application. At the same time, for those skilled in the art, according to the idea of ​​the present application, there may be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. An energy storage device (100), characterized in that: The invention comprises an end cap assembly (10), an electrode assembly (20), a partition member (30), a protective member (40) and a shell (50), The partition piece (30) is provided with a through groove (37) and a through hole (34), the through groove (37) and the through hole (34) both penetrate the partition piece (30) along the thickness direction of the partition piece (30), and the through groove (37) and the through hole (34) are arranged at intervals; The protective member (40) is provided with a first accommodating cavity (41), the first accommodating cavity (41) having a first opening (42), the partition member (30) and the electrode assembly (20) are both accommodated in the first accommodating cavity (41), the electrode assembly (20) passes through the through groove (37), and the electrode assembly (20) is sealed and connected to the groove wall of the through groove (37); the partition member (30) is sealed and connected to the cavity wall of the first accommodating cavity (41), and divides the first accommodating cavity (41) into a first sub-accommodating cavity (41A) and a second sub-accommodating cavity (41B), the first sub-accommodating cavity (41A) is in communication with the first opening (42), and the through hole (34) is in communication with the first sub-accommodating cavity (41A) and the second sub-accommodating cavity (41B); The housing (50) is provided with a second opening (52), the protective member (40) is received in the housing (50) through the second opening (52), the end cover assembly (10) is mounted on the second opening (52) and seals the second opening (52), the end cover assembly (10) is opposite to the first opening (42) and the end cover assembly (10) is connected to the protective member (40), and the electrolyte of the energy storage device (100) is received in the housing (50) and the first receiving cavity (41); A pressure difference can be generated between the first sub-accommodating chamber (41A) and the second sub-accommodating chamber (41B), so that the electrolyte in the first sub-accommodating chamber (41A) flows into the second sub-accommodating chamber (41B) through the through hole (34).

2. The energy storage device (100) according to claim 1, characterized in that: The ratio of the height h1 of the through hole (34) to the height h2 of the partition member (30) is 0.05-0.

1.

3. The energy storage device (100) according to claim 1, characterized in that: The protective member (40) comprises a first side wall (46), wherein the first side wall (46) is arranged at an end away from the end cover assembly (10), and the ratio of the distance L1 between the partition member (30) and the first side wall (46) to the length L2 of the protective member (40) is 0.1-0.

15.

4. The energy storage device (100) according to claim 1, characterized in that: The through hole (34) is a circular hole, and the ratio of the hole diameter d of the through hole (34) to the height h2 of the partition member (30) is 0.03-0.

05.

5. The energy storage device (100) according to claim 1, characterized in that: The partition piece (30) comprises two side plates (33), the two side plates (33) are arranged opposite to each other along the length direction of the partition piece (30), and the through hole (34) comprises two groups of sub-through holes, the two groups of sub-through holes respectively penetrate the two side plates (33), and the two groups of sub-through holes are arranged opposite to each other along the length direction of the partition piece (30).

6. The energy storage device (100) according to any one of claims 1 to 4, characterized in that: The partition piece (30) comprises two side plates (33), and the two side plates (33) are arranged opposite to each other along the length direction of the partition piece (30); the partition piece (30) is provided with a first protrusion (35) and a second protrusion (36), and the first protrusion (35) and the second protrusion (36) are respectively protruded on the two side plates (33) and both protrude toward the through groove (37), and along the length direction of the partition piece (30), the first protrusion (35) and the second protrusion (36) are arranged opposite to each other; There are two electrode assemblies (20), and the two electrode assemblies (20) are spaced apart along the thickness of the electrode assemblies (20). The two electrode assemblies (20) are stacked in a stacked manner, a first recess (26A) and a second recess (26B) are formed between the two electrode assemblies (20), and the first recess (26A) and the second recess (26B) are arranged opposite to each other along the width direction of the electrode assembly (20); The first protrusion (35) is inserted into the first recess (26A) and closes the gap between the electrode assemblies (20), and the surface of the first protrusion (35) is pressed against the inner wall surface of the first recess (26A); The second protrusion (36) is inserted into the second recess (26B) and closes the gap between the electrode assemblies (20), and the surface of the second protrusion (36) is pressed against the inner wall surface of the second recess (26B).

7. The energy storage device (100) according to claim 6, characterized in that: The first protrusion (35) and the second protrusion (36) are both integrally formed with the side plate (33).

8. The energy storage device (100) according to any one of claims 1 to 4, characterized in that: The partition member (30) and the protective member (40) are integrally formed.

9. The energy storage device (100) according to claim 1, characterized in that: The partition member (30) is also provided with a one-way valve, and along the thickness direction of the partition member (30), the orthographic projection of the one-way valve completely covers the orthographic projection of the through hole (34); the one-way valve only allows fluid to flow from the first sub-accommodating chamber (41A) to the second sub-accommodating chamber (41B).

10. An energy storage module, characterized in that: It comprises a plurality of energy storage devices (100) as claimed in claims 1 to 9, wherein the plurality of energy storage devices (100) are electrically connected.

11. An electrical device, characterized in that: It comprises the energy storage module as described in claim 10, and the energy storage module is used to supply power to the electrical equipment.

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