Battery monomer, battery device, energy storage device and electric equipment

Abstract

The utility model relates to the technical field of battery equipment, and discloses a battery monomer, a battery device, an energy storage device and electric equipment. Wherein the battery monomer comprises a metal shell and a shell cover assembly, and the shell cover assembly covers the metal shell to form an accommodating space; the electrode assembly is contained in the containing space, the electrode assembly comprises a battery cell body and a tab, and the tab is electrically connected to the end, facing the shell cover assembly, of the battery cell body; the pole structure and the pressure relief mechanism are both arranged on the shell cover assembly, and the tab is electrically connected with the pole; and the circumferential insulating layer circumferentially wraps the battery cell body, in the direction from the battery cell body to the shell cover assembly, the first end edge of the circumferential insulating layer exceeds the tab and is in sealed connection with the circumferential edge of the shell cover assembly, and the circumferential insulating layer is a part made of a temperature-resistant material. By applying the technical scheme, the problem of thermal runaway caused by lap joint short circuit between the tab of the electrode assembly and the inner wall of the metal shell after the insulating layer of the battery monomer is heated and melted is solved.

Description

Technical Field

[0001] This application belongs to the field of battery equipment technology, and in particular relates to a battery cell, battery device, energy storage device and electrical equipment. Background Technology

[0002] In the battery cells of this technology, a metal casing is used to encapsulate the electrode assembly, and a PP insulating layer is used to wrap the electrode assembly, thereby insulating the electrode assembly from the metal casing. The PP insulating layer has a melting point of approximately 155℃, which meets the temperature resistance requirements of the battery cell during charging and discharging.

[0003] A battery device is formed by assembling multiple battery cells, which can be connected in series, parallel, or mixed to store or provide electrical energy. When a battery cell experiences thermal runaway, a violent electrochemical reaction occurs inside the cell, generating a large amount of high-temperature flue gas. This high-temperature flue gas is ejected from the cell's pressure relief mechanism, and subsequently affects other battery cells surrounding the thermally runaway cell, with the cells adjacent to the runaway cell being most significantly affected.

[0004] When a battery cell adjacent to the one experiencing thermal runaway is heated, the temperature of its metal casing rises rapidly. Typically, the temperature of the metal casing exceeds the melting point of the PP insulation layer, causing it to melt. This melted insulation layer easily leads to direct contact between the electrode tabs and the inner wall of the metal casing, causing a short circuit in the battery cell and resulting in thermal runaway. This can then cascade through multiple battery cells in the battery pack, causing a chain reaction of thermal runaway and ultimately resulting in system-wide thermal runaway, posing a significant hazard. Utility Model Content

[0005] The purpose of this application is to provide a battery cell, battery device, energy storage device, and electrical equipment, including but not limited to solving the problem that thermal runaway occurs when the insulation layer of the battery cell melts due to heat, causing the electrode tabs of the electrode assembly to short-circuit with the inner wall of the metal casing.

[0006] To achieve the above objectives, according to a first aspect of an embodiment of this application, a battery cell is provided, comprising:

[0007] A metal housing and a cover assembly, wherein the cover assembly is fitted onto the metal housing to form a receiving space;

[0008] An electrode assembly is housed in a housing space. The electrode assembly includes a battery cell body and tabs electrically connected to the battery cell body.

[0009] The electrode post structure is located on the housing assembly, and the electrode tab is electrically connected to the electrode post.

[0010] The pressure relief mechanism is located on the housing assembly;

[0011] A circumferential insulating layer is circumferentially covered around the cell body. In the direction from the cell body to the cover assembly, the first edge of the circumferential insulating layer near the tab extends beyond the tab and is sealed to the circumferential edge of the cover assembly on the side facing the electrode assembly. The circumferential insulating layer is a component made of a heat-resistant material.

[0012] When one end of the battery cell casing assembly provided in the embodiments of this application is subjected to the heat effect of high-temperature flue gas ejected from other battery cells that have experienced thermal runaway, causing the temperature of the metal casing to rise, the circumferential insulating layer is made of a heat-resistant material and can withstand the high temperature without melting. Thus, the circumferential insulating layer is always blocked between the tab and the inner wall of the metal casing, preventing the tab from directly contacting the inner wall of the metal casing and causing a short circuit. This effectively reduces the probability of thermal runaway of the battery cell and improves the safety of the battery cell.

[0013] In some embodiments of this application, the battery cell further includes an end insulating layer disposed at the end of the cell body away from the tab, and the circumferential edge of the end insulating layer is connected to a second end edge of the circumferential insulating layer away from the tab. The end insulating layer is made of a heat-resistant material. This further protects the electrode assembly and prevents a short circuit caused by contact between the end of the cell body away from the tab and the metal casing.

[0014] In some embodiments of this application, the melting point of the circumferential insulating layer and / or the melting point of the end insulating layer are greater than 200°C, thereby being able to withstand high temperatures without melting, preventing the electrode assembly from directly contacting the inner wall of the metal casing and causing a short circuit, and effectively reducing the probability of thermal runaway of the battery cell.

[0015] In some embodiments of this application, the circumferential edge of the end insulation layer is sealed and bonded to the second end edge of the circumferential insulation layer away from the tab, so as to prevent electrolyte leakage to the metal housing 10 and protect the metal housing 10 from electrolyte corrosion.

[0016] In some embodiments of this application, the circumferential insulating layer and the end insulating layer are integrally formed structures.

[0017] In some embodiments of this application, the circumferential insulating layer and / or the end insulating layer are components made of PBT, PET or PFA materials.

[0018] In some embodiments of this application, the circumferential insulating layer and / or the end insulating layer include at least one first insulating layer and at least one second insulating layer stacked together. The first insulating layer is located between the cell body and the second insulating layer. The melting point of the second insulating layer is higher than that of the first insulating layer, and the second insulating layer is a component made of a heat-resistant material. By withstanding high temperatures without melting, regardless of whether the first insulating layer melts, the second insulating layer always acts as a barrier between the tab and the inner wall of the metal casing, preventing direct contact between the tab and the inner wall of the metal casing that could lead to a short circuit, effectively reducing the probability of thermal runaway in the battery cell.

[0019] In some embodiments of this application, the melting point of the second insulating layer is greater than 200°C, thereby enabling it to withstand high temperatures without melting.

[0020] In some embodiments of this application, the cover assembly includes a stacked metal cover and an insulating inner layer, the pole structure is insulated from the metal cover, the circumferential edge of the insulating inner layer is sealed to a first end edge, and the circumferential edge of the metal cover is welded to the circumferential edge of the opening end of the metal shell.

[0021] In some embodiments of this application, the battery cell is a square battery cell or a cylindrical battery cell.

[0022] According to a second aspect of an embodiment of this application, a battery device is provided. The battery device includes a battery cell as described above, the battery cell being used to store or provide electrical energy.

[0023] According to a third aspect of the embodiments of this application, an energy storage device is provided. Wherein:

[0024] The energy storage device includes battery cells as described above, which are used to store or provide electrical energy;

[0025] Alternatively, the energy storage device may include a battery device as described above, which is used to store or provide electrical energy.

[0026] According to a fourth aspect of an embodiment of this application, an electrical appliance is provided. The electrical appliance includes an electrical load; and,

[0027] The electrical equipment also includes multiple battery cells as described above, and the electrical load is electrically connected to the multiple battery cells;

[0028] Alternatively, the electrical equipment may also include a battery device as described above, with the electrical load electrically connected to the battery device;

[0029] Alternatively, the electrical equipment may also include an energy storage device as described above, with the electrical load electrically connected to the energy storage device. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the structure of a battery cell according to an embodiment of this application;

[0032] Figure 2 for Figure 1 The diagram shows a front view of a single battery cell;

[0033] Figure 3 for Figure 1 A schematic diagram of the exploded battery cell is shown.

[0034] Figure 4 for Figure 2 Cross-sectional view along the AA direction;

[0035] Figure 5 for Figure 4 Enlarged view of point B in the middle;

[0036] Figure 6 This is an exploded view of another battery cell according to an embodiment of this application;

[0037] Figure 7 This is a schematic diagram of the structure of the circumferential insulating layer and / or the end insulating layer in a battery cell according to an embodiment of this application;

[0038] Figure 8 This is an exploded view of a battery device according to an embodiment of this application;

[0039] Figure 9 This is a schematic diagram of the structure of an energy storage device according to an embodiment of this application;

[0040] Figure 10 This is a schematic diagram of the structure of an electrical device according to an embodiment of this application.

[0041] The figures in the diagram are labeled as follows:

[0042] 100. Battery cell;

[0043] 10. Metal casing; 11. Receiving space; 12. Open end;

[0044] 20. Shell and cover assembly; 21. Metal cover; 22. Insulating inner layer;

[0045] 30. Electrode assembly; 31. Battery cell body; 32. Tab;

[0046] 40. Circumferential insulation layer; 41. First end edge; 42. Second end edge;

[0047] 50. End insulation layer;

[0048] 61. First insulating layer; 62. Second insulating layer;

[0049] 71. Pole post structure; 72. Pressure relief mechanism; 73. Injection port; 74. Adapter plate;

[0050] 200. Battery assembly; 201. Box body; 202. Box cover; 203. Assembly space;

[0051] 300. Energy storage device; 301. Cabinet;

[0052] 400. Electrical equipment; 410. Electrical load; 420. Control device; 430. Chassis; 440. Wheel. Detailed Implementation

[0053] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0054] In the description of this application, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0055] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0056] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0057] Currently, judging from market trends, the application of battery devices is becoming increasingly widespread. Battery devices are not only used in energy storage power systems such as hydropower, thermal power, wind power, and solar power plants (battery devices used in these applications are generally referred to as energy storage batteries), but also widely used in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace (battery devices used in these applications are generally referred to as power batteries). With the continuous expansion of the application fields of battery devices, users' requirements for the safety of battery devices are also constantly increasing.

[0058] In the battery cells of this technology, a metal casing is used to encapsulate the electrode assembly, and a PP insulating layer is used to wrap the electrode assembly, thereby insulating the electrode assembly from the metal casing. When the tabs of the electrode assembly are electrically connected to the terminal structures on the casing cover and the casing cover is closed onto the open end of the metal casing, the casing cover and terminal structures apply a certain degree of compressive bending force to the tabs, causing the tabs to bend towards the insulating layer or even abut against it. The PP insulating layer has a melting point of approximately 155℃, which meets the temperature resistance requirements of the battery cell during charging and discharging.

[0059] PP material, Polypropylene, is a non-toxic, odorless, tasteless, milky-white, highly crystalline polymer, and is a type of plastic.

[0060] A battery device is formed by assembling multiple battery cells, which can be connected in series, parallel, or mixed to store or provide electrical energy. When a battery cell experiences thermal runaway, a violent electrochemical reaction occurs inside the cell, generating a large amount of high-temperature flue gas. This high-temperature flue gas is ejected from the cell's pressure relief mechanism, and subsequently affects other battery cells surrounding the thermally runaway cell, with the cells adjacent to the runaway cell being most significantly affected.

[0061] When a battery cell adjacent to the one experiencing thermal runaway is heated, the temperature of its metal casing rises rapidly. Typically, the temperature of the metal casing exceeds the melting point of the PP insulation layer, causing it to melt. This melted insulation layer easily leads to direct contact between the electrode tabs and the inner wall of the metal casing, causing a short circuit in the battery cell and resulting in thermal runaway. This can then cascade through multiple battery cells in the battery pack, causing a chain reaction of thermal runaway and ultimately resulting in system-wide thermal runaway, posing a significant hazard.

[0062] Based on the above considerations, embodiments of this application provide a battery cell, and battery devices, energy storage devices, and electrical equipment are assembled and manufactured using the battery cell provided in the embodiments of this application. The battery cell includes a metal casing, a casing assembly, an electrode assembly, a terminal structure, a pressure relief mechanism, and a circumferential insulating layer. The casing assembly covers the metal casing to form a receiving space, and the electrode assembly is received within the receiving space. The electrode assembly includes a cell body and a tab electrically connected to the cell body. The tab is located at the end of the cell body facing the casing assembly. The terminal structure is disposed on the casing assembly, and the tab is electrically connected to the terminal structure. The pressure relief mechanism is disposed on the casing assembly and is used to release high-temperature flue gas inside the battery cell when thermal runaway occurs. The circumferential insulating layer circumferentially covers the cell body, and the first edge of the circumferential insulating layer near the tab extends beyond the tab and is sealed to the circumferential edge of the casing assembly on the side facing the electrode assembly, thereby preventing the tab from contacting the inner wall of the metal casing. Furthermore, the circumferential insulating layer is a component made of a heat-resistant material. Thus, when one end of the battery cell casing assembly provided in the embodiments of this application is subjected to the heat effect of high-temperature flue gas ejected by other battery cells that have experienced thermal runaway, causing the temperature of the metal casing to rise, the circumferential insulating layer, being a component made of heat-resistant material, can withstand the high temperature without melting. As a result, the circumferential insulating layer always blocks the connection between the tab and the inner wall of the metal casing, preventing the tab from directly contacting the inner wall of the metal casing and causing a short circuit. This effectively reduces the probability of thermal runaway in the battery cell and improves the safety of the battery cell in use.

[0063] To illustrate the technical solutions provided by the embodiments of this application, the following detailed description is provided in conjunction with specific drawings and embodiments.

[0064] According to a first aspect of the embodiments of this application, embodiments of this application provide a battery cell 100. For example... Figures 1 to 5As shown, the battery cell 100 includes a metal casing 10, a casing cover assembly 20, an electrode assembly 30, a terminal structure 71, a pressure relief mechanism 72, and a circumferential insulating layer 40. The casing cover assembly 20 covers the metal casing 10 to form a receiving space 11. The electrode assembly 30 is received in the receiving space 11. The electrode assembly 30 includes a cell body 31 and a tab 32 electrically connected to the cell body 31. The tab 32 is located at the end of the cell body 31 facing the casing cover assembly 20. The terminal structure 71 is disposed on the casing cover assembly 20. The tab 32 and the terminal structure 71 are electrically connected via an adapter piece 74. The pressure relief mechanism 72 is disposed on the casing cover assembly 20 and is used to release pressure when the battery cell 100 experiences thermal runaway. The high-temperature flue gas inside the battery cell 100 is released. The circumferential insulating layer 40 circumferentially covers the cell body 31. In the direction from the cell body 31 to the cover assembly 20, the first end edge 41 of the circumferential insulating layer 40 near the tab 32 extends beyond the tab 32. The first end edge 41 of the circumferential insulating layer 40 near the tab 32 is sealed to the circumferential edge of the cover assembly 20 on the side facing the electrode assembly 30 to prevent the tab 32 from contacting the inner wall of the metal casing 10. The circumferential insulating layer 40 is a component made of heat-resistant material.

[0065] When assembling the battery cell 100, after the electrode tab 32 of the electrode assembly 30 is electrically connected to the terminal post structure 71 provided on the cover assembly 20, and the cover assembly 20 is closed on the opening end 12 of the metal casing 10, the cover assembly 20 and the terminal post structure 71 apply a certain degree of compressive bending force to the electrode tab 32, causing the electrode tab 32 to bend towards the metal casing 10 or even abut against the circumferential insulating layer 40. In this way, when the battery cell 100 is normally charging and discharging, the circumferential insulating layer 40 can always ensure insulation between the electrode tab 32 and the metal casing 10, and the circumferential insulating layer 40 can withstand the temperature rise changes of the electrode tab 32 during charging and discharging, thus better meeting the heat resistance requirements.

[0066] The pressure relief mechanism 72 is an element or component that is activated to release internal pressure when the internal pressure or temperature of the battery cell 100 reaches a predetermined threshold. "Activation" means that the pressure relief mechanism 72 performs an action, thereby releasing the internal pressure and temperature of the battery cell 100. The action of the pressure relief mechanism 72 may include, but is not limited to, at least a portion of the pressure relief mechanism 72 rupturing, tearing, or melting. After activation, the high-temperature flue gas inside the battery cell 100 will be discharged outward from the pressure relief mechanism 72. The predetermined threshold can be adjusted according to different design requirements. The predetermined threshold may depend on one or more materials of the positive electrode, negative electrode, separator, and electrolyte of the electrode assembly 30 in the battery cell 100. The pressure relief mechanism 72 may employ elements or components that are sensitive to pressure or temperature; that is, when the internal pressure or temperature of the battery cell 100 reaches the predetermined threshold, the pressure relief mechanism 72 is activated, thereby forming a channel for releasing internal pressure (i.e., the pressure relief area of ​​the pressure relief mechanism 72).

[0067] Thus, when one end of the casing assembly 20 of the battery cell 100 provided in the embodiments of this application is subjected to the heat effect of the high-temperature flue gas ejected by other battery cells 100 that have experienced thermal runaway, causing the temperature of the metal casing 10 to rise, since the circumferential insulating layer 40 is a component made of heat-resistant material, the circumferential insulating layer 40 can withstand the high temperature without melting. As a result, the circumferential insulating layer 40 is always blocked between the tab 32 and the inner wall of the metal casing 10, preventing the tab 32 from directly contacting the inner wall of the metal casing 10 and causing a short circuit. This effectively reduces the probability of the battery cell 100 experiencing thermal runaway and improves the safety of the battery cell 100 in use.

[0068] To further protect the electrode assembly 30 and prevent a short circuit caused by the end of the battery cell body 31 furthest from the tab 32 contacting the metal casing 10, in some embodiments of this application, based on the circumferential insulation layer 40 circumferentially covering the circumferential sidewalls of the electrode assembly 30, such as... Figure 3 and Figure 4As shown, the battery cell 100 also includes an end insulating layer 50, which is disposed at the end of the cell body 31 away from the tab 32. The circumferential edge of the end insulating layer 50 is connected to the second end edge 42 of the circumferential insulating layer 40 away from the tab 32. The end insulating layer 50 is made of a heat-resistant material. Thus, when the battery cell 100 is subjected to heat, causing the temperature of the metal casing 10 to rise, the circumferential insulating layer 40, made of heat-resistant material, can withstand the high temperature without melting, thus partially blocking heat from acting on the cell body 31 and protecting the separator of the cell body 31. Furthermore, the circumferential insulating layer 40 always blocks the circumferential sidewall of the cell body 31 from the inner wall of the metal casing 10, thereby preventing short circuits between the circumferential sidewall of the cell body 31 and the metal casing 10. Furthermore, the end insulation layer 50, made of heat-resistant material, can withstand high temperatures without melting. The end insulation layer 50 always blocks the connection between the end of the cell body 31 away from the tab 32 and the bottom of the metal casing 10, thereby preventing the end of the cell body 31 from short-circuiting with the metal casing 10. This provides more comprehensive protection for the electrode assembly 30.

[0069] In some other embodiments of this application, the circumferential insulating layer 40 and the end insulating layer 50 of the battery cell 100 can both be made of heat-resistant material, or they can be combined to cover the electrode assembly 30, i.e., the circumferential insulating layer 40 is made of heat-resistant material while the end insulating layer 50 is still made of PP material. This is because when a battery cell 100 in the battery device 200 experiences thermal runaway, the high-temperature fumes emitted by that battery cell 100 first affect the end of the surrounding battery cells 100 where the casing assembly 20 is located. Then, the high-temperature fumes gradually spread and affect the other end of the battery cell 100 away from the casing assembly 20. Furthermore, because the battery device 200 is equipped with other heat-insulating components, the time it takes for the high-temperature fumes to spread and affect the other end of the battery cell 100 away from the casing assembly 20 is slowed down, and the degree of impact of the high-temperature fumes on the other end of the battery cell 100 away from the casing assembly 20 is reduced. Therefore, even though the end insulation layer 50 is still made of PP material, it can still meet the heat resistance requirements and always block the end of the cell body 31 away from the tab 32 between the end and the bottom of the metal casing 10, thereby preventing the end of the cell body 31 from short-circuiting with the metal casing 10.

[0070] When a single battery cell 100 in the battery device 200 experiences thermal runaway, the high-temperature fumes emitted by that battery cell 100 can reach a temperature of approximately 200°C on the end of the casing assembly 20 of the surrounding battery cells 100. Therefore, in the embodiments of this application, the melting point of the circumferential insulating layer 40 is greater than 200°C, enabling it to withstand high temperatures without melting. This ensures that the circumferential insulating layer 40 remains between the tab 32 and the inner wall of the metal casing 10, preventing direct contact between the tab 32 and the inner wall of the metal casing 10, thus preventing a short circuit and effectively reducing the probability of thermal runaway in the battery cell 100, thereby improving the safety of the battery cell 100. Furthermore, the embodiments of this application optimize the design so that the melting point of the end insulating layer 50 is greater than 200°C.

[0071] In some embodiments of this application, the circumferential edge of the end insulating layer 50 is sealed and bonded to the second end edge 42 of the circumferential insulating layer 40 away from the tab 32. Thus, when electrolyte is injected through the injection hole 73 on the cover assembly 20, the electrolyte will not leak from the mating position between the circumferential edge of the end insulating layer 50 and the second end edge 42 of the circumferential insulating layer 40 away from the tab 32 into the metal housing 10, protecting the metal housing 10 from electrolyte corrosion.

[0072] In some other embodiments of this application, the circumferential insulating layer 40 and the end insulating layer 50 are integrally molded. By using an integral injection molding process to manufacture the circumferential insulating layer 40 and the end insulating layer 50, the integrity of the circumferential insulating layer 40 and the end insulating layer 50 is improved, and the production efficiency of processing and manufacturing the circumferential insulating layer 40 and the end insulating layer 50 is increased.

[0073] The circumferential insulating layer 40 and / or the end insulating layer 50 are components made of PBT, PET, or PFA materials. PBT, or polybutylene terephthalate, is an important thermoplastic polyester and one of the five major engineering plastics. The melting point of PBT is 225℃-235℃. PET, or polyethylene glycol terephthalate, is the most important type of thermoplastic polyester, and together with PBT, it is collectively referred to as thermoplastic polyester or saturated polyester. The melting point of PET is 250℃-265℃. PFA, or Polyfluoroalkoxy, Teflon PFA, is generally abbreviated as PFA, and its melting point ranges from 260℃ to 327℃. Furthermore, the circumferential insulating layer 40 and / or the end insulating layer 50 made of PBT, PET, or PFA materials are resistant to electrolytes, which helps extend the service life of the battery cell 100.

[0074] In some embodiments of this application, such as Figure 7 As shown, the circumferential insulating layer 40 and / or the end insulating layer 50 include at least one first insulating layer 61 and at least one second insulating layer 62 stacked together. That is, in this embodiment, the circumferential insulating layer 40 and / or the end insulating layer 50 are composite layer structures. The first insulating layer 61 is located between the cell body 31 and the second insulating layer 62. The melting point of the second insulating layer 62 is greater than that of the first insulating layer 61, and the second insulating layer 62 is a component made of a heat-resistant material. Thus, by withstanding high temperatures without melting, regardless of whether the first insulating layer 61 melts, the second insulating layer 62 always blocks the electrode 32 from the inner wall of the metal casing 10, preventing the electrode 32 from directly contacting the inner wall of the metal casing 10 and causing a short circuit. This effectively reduces the probability of thermal runaway of the battery cell 100 and improves the safety of the battery cell 100.

[0075] The second insulating layer 62 has a melting point greater than 200°C, thus it can withstand high temperatures without melting. Furthermore, the first insulating layer 61 can be made of PP material, which is inexpensive and helps reduce costs.

[0076] In some embodiments of this application, such as Figure 3 As shown, the housing assembly 20 includes a stacked metal cover 21 and an insulating inner layer 22. The electrode structure 71 is insulated from the metal cover 21, and the circumferential edge of the insulating inner layer 22 is sealed to the first end edge 41. Thus, the circumferential insulating layer 40, the end insulating layer 50, and the insulating inner layer 22 form a sealed space to contain the electrolyte, preventing electrolyte leakage and contact with the metal housing 10 and the metal cover 21, which could cause corrosion. Furthermore, the circumferential edge of the metal cover 21 is welded to the circumferential edge of the opening end 12 of the metal housing 10. Laser welding is preferably used, as it offers high welding efficiency and quality, ensuring that the housing assembly 20 is firmly connected to the opening end 12 of the metal housing 10.

[0077] The battery cell 100 provided in the embodiments of this application can be Figures 1 to 4 The square battery cell shown. Alternatively, battery cell 100 can also be... Figure 6 The cylindrical battery cell shown.

[0078] In the embodiments of this application, the battery cell 100 can be a secondary battery, which refers to a battery cell 100 that can be recharged after discharge to activate the active materials and continue to be used. The battery cell 100 can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and the embodiments of this application are not limited to this.

[0079] According to a second aspect of the embodiments of this application, the embodiments of this application also provide a battery device 200. The following description uses an example of assembling a battery device 200 using square battery cells (i.e., a square battery). Figure 8 As shown. The implementation scheme of assembling the battery device 200 using cylindrical battery cells can be specifically referred to as the implementation scheme of assembling the battery device 200 using square battery cells, and will not be repeated here.

[0080] like Figure 8 As shown, the battery device 200 includes a main body 201, a cover 202, and multiple battery cells 100 as described above. The cover 202 closes onto the open end of the main body 201, and the main body 201 and the cover 202 together form an assembly space 203. The multiple battery cells 100 are arrayed and assembled within the assembly space 203. The battery cells 100 are used to store electrical energy or supply power.

[0081] According to a third aspect of the embodiments of this application, embodiments of this application also provide an energy storage device 300. In some embodiments of this application, the energy storage device 300 includes a battery device 200 as described above, that is, the energy storage device 300 uses one battery device 200 or multiple battery devices 200 connected in series, parallel, or mixed, such that these battery devices 200 are used to store electrical energy or provide electrical energy. In other embodiments of this application, the energy storage device 300 includes multiple battery cells 100 as described above, that is, the energy storage device 300 uses multiple battery cells 100 connected in series, parallel, or mixed, such that these battery cells 100 are used to store electrical energy or provide electrical energy.

[0082] The energy storage device 300 can be a small, portable device, such as a convenient energy storage battery used for outdoor tourism and camping, or a portable energy storage battery used by street vendors. The energy storage device 300 can also be a large, fixed, high-power industrial-grade device, such as a large energy storage power station used in a power plant. The energy storage device 300 can be used in energy storage power stations, wind power generation systems, solar power generation systems, mobile power systems, or temporary power supply systems. The energy storage device 300 can store electrical energy as needed and output it when appropriate. For example, the energy storage device 300 can store electrical energy during off-peak hours and provide power to relevant users or electrical equipment during peak hours. Other examples include independent power supply energy storage cabinets or energy storage containers used on construction sites or in factories, and larger, portable energy storage cabinets or energy storage containers used at large event venues.

[0083] like Figure 9As shown, the energy storage device 300 provided in the embodiments of this application is preferably an energy storage cabinet, which includes a cabinet 301 and a plurality of battery devices 200, which are stacked and assembled in the cabinet 301.

[0084] In some embodiments of this application, the energy storage device 300 may include modules such as a thermal management module, a main control module, a central control module, a power distribution module, and a fire protection module.

[0085] As an example, the thermal management module may include a liquid cooling unit that supplies coolant to each battery cell 100 or each battery device 200 via pipelines for regulating the temperature of the battery cell 100.

[0086] As an example, the main control module can serve as a battery management unit for multiple battery cells 100 or multiple battery devices 200, used to monitor and manage these cells. The main control module can monitor information such as current, voltage, power, or temperature of the multiple battery cells 100 or multiple battery devices 200. For example, it can control the charging and discharging current and voltage of the multiple battery cells 100 or multiple battery devices 200. The main control module includes modules such as an auxiliary battery management unit (SBMU) and a fusion switch.

[0087] As an example, the central control module can serve as the battery management unit of the energy storage device 300, used to monitor and manage the energy storage device 300. The central control module can monitor information such as the current, voltage, power, state of charge, or temperature of the energy storage device 300. For example, it can control the charging and discharging current and voltage of the energy storage device 300. As an example, the central control module includes modules such as an insulation monitoring module (IMM), a master battery management unit (MBMU), an Ethernet (ETH) module, and a fiber optic conversion module.

[0088] As an example, the fire protection module includes a control panel, detectors, alarm devices, etc., for detecting, alarming, or extinguishing fires in the energy storage device 300.

[0089] As an example, the power distribution module can be used to distribute power to the modules in the energy storage device 300 that require electricity.

[0090] According to a fourth aspect of the embodiments of this application, embodiments of this application also provide an electrical appliance 400, which includes an electrical load 410.

[0091] Electrical equipment 400 includes, but is not limited to, electric toys, power tools, electric vehicles, electric cars, ships, and spacecraft. Electric toys may include, but are not limited to, stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys. Spacecraft may include, but are not limited to, airplanes, rockets, space shuttles, and spacecraft.

[0092] In some embodiments of this application, the electrical device 400 further includes an energy storage device 300 as described above. That is, the electrical device 400 employs one energy storage device 300 or multiple energy storage devices 300 connected in series, parallel, or in a mixed configuration, and the electrical load 410 is electrically connected to the energy storage device 300. The battery device 200 of the energy storage device 300 is used to store electrical energy, or the battery device 200 of the energy storage device 300 is used to provide electrical energy to the electrical load 410, thereby enabling the electrical load 410 to operate normally.

[0093] Alternatively, in some other embodiments of this application, the electrical device 400 further includes a battery device 200 as described above. That is, the electrical device 400 uses one battery device 200 or multiple battery devices 200 connected in series, parallel, or mixed connection, and the electrical load 410 is electrically connected to the battery device 200. The battery device 200 is used to store electrical energy, or the battery device 200 is used to provide electrical energy to the electrical load 410, thereby enabling the electrical load 410 to operate normally.

[0094] Alternatively, in some other embodiments of this application, the electrical device 400 further includes a plurality of battery cells 100 as described above. That is, the electrical device 400 uses a plurality of battery cells 100 connected in series, parallel, or in a mixed configuration, and the electrical load 410 is electrically connected to the plurality of battery cells 100. The plurality of battery cells 100 are used to store electrical energy, or the plurality of battery cells 100 are used to provide electrical energy to the electrical load 410, thereby enabling the electrical load 410 to operate normally.

[0095] Among them, the electrical equipment 400 is an electric vehicle, and it is assembled using a battery device 200, such as Figure 10As shown, the battery device 200 is mounted on the frame 430 of the electric vehicle. The electric vehicle includes the frame 430, a drive motor, and wheels 440. The battery device 200 and the drive motor are both fixedly mounted on the frame 430, and the wheels 440 are rotatably connected to the frame 430. The battery device 200 is electrically connected to the drive motor, and the drive motor is driven by the wheels 440. When the battery device 200 provided in this application supplies power to the drive motor (the drive motor is one of the electrical loads 410 of the electrical equipment 400), the drive motor drives the wheels 440 to rotate, enabling the electric vehicle to drive normally. Furthermore, the electric vehicle includes a control device 420, which is mounted on the frame 430 and electrically connected to the battery device 200. The control device 420 is used to control and monitor the charging and discharging status of the battery device 200. In some electric vehicles, the battery housing of the battery device 200 can be part of the chassis structure of the electric vehicle. For example, a portion of the battery box can be at least part of the floor of the electric vehicle, or a portion of the battery box can be at least part of the crossbeams and longitudinal beams of the electric vehicle.

[0096] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery cell, comprising: a metal casing and a casing cover assembly, the casing cover assembly covering the metal casing to form a containing space; an electrode assembly contained in the containing space, the electrode assembly comprising an electrode core body and a tab electrically connected to the electrode core body, the tab being located at an end of the electrode core body facing the casing cover assembly; a post structure provided on the casing cover assembly, the tab being electrically connected to the post structure; and a pressure relief mechanism provided on the casing cover assembly; characterized in that the battery cell further comprises: a circumferential insulation layer circumferentially covering the electrode core body, the circumferential insulation layer being located close to a first end edge of the tab and extending beyond the tab in a direction from the electrode core body to the casing cover assembly, and a circumferential edge of the circumferential insulation layer being sealingly connected to a circumferential edge of a side of the casing cover assembly facing the electrode assembly, and the circumferential insulation layer being made of a temperature-resistant material. 2.The battery cell of claim 1, characterized in that: the battery cell further comprises an end insulation layer provided at an end of the electrode core body away from the tab, a circumferential edge of the end insulation layer being connected to a second end edge of the circumferential insulation layer away from the tab, and the end insulation layer being made of a temperature-resistant material. 3.The battery cell of claim 2, characterized in that: a melting point of the circumferential insulation layer and / or a melting point of the end insulation layer is greater than 200 ℃. 4.The battery cell of claim 2, characterized in that: the circumferential edge of the end insulation layer is sealingly bonded to the second end edge. 5.The battery cell of claim 2, characterized in that: the circumferential insulation layer and the end insulation layer are integrally formed. 6.The battery cell of any one of claims 2-5, characterized in that: the circumferential insulation layer and / or the end insulation layer is made of a PBT material, a PET material or a PFA material. 7.The battery cell of any one of claims 2-5, characterized in that: the circumferential insulation layer and / or the end insulation layer comprises at least one first insulation layer and at least one second insulation layer stacked, the first insulation layer being located between the electrode core body and the second insulation layer, and a melting point of the second insulation layer being greater than a melting point of the first insulation layer. 8.The battery cell of claim 7, characterized in that: the melting point of the second insulation layer is greater than 200 ℃. 9.The battery cell of any one of claims 1-5, characterized in that: the casing cover assembly comprises a metal cover body and an insulation inner layer stacked, the post structure being insulated from the metal cover body, a circumferential edge of the insulation inner layer being sealingly connected to the first end edge, and a circumferential edge of the metal cover body being welded to a circumferential edge of an open end of the metal casing. 10.The battery cell of claim 9, characterized in that: the battery cell is a square battery cell or a cylindrical battery cell. A battery cell as claimed in any one of claims 1-10 is used for storing or providing electric energy. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 11. A battery device characterized by comprising: ​ 12. An energy storage device, characterized in that, the energy storage device comprises the battery cell of any one of claims 1-10, the battery cell being used to store or provide electrical energy; or, the energy storage device comprises the battery device of claim 11, the battery device being used to store or provide electrical energy.

13. An electrical device, characterized by comprises an electrical load; the electrical load is electrically connected to the plurality of battery cells; or, the electrical load is electrically connected to the battery device; or, the electrical load is electrically connected to the energy storage device.

Images