Cylindrical 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 cylindrical battery monomer, a battery device, an energy storage device and electric equipment. Wherein the cylindrical battery monomer comprises a cylindrical shell and at least one end cover, and the end cover covers the opening end of the cylindrical shell to form an accommodating space; the electrode assembly is accommodated in the accommodating space, and the electrode assembly comprises a battery cell body and a tab connected to the battery cell body; the current collecting plate is electrically connected with the tab and is positioned in the accommodating space, the current collecting plate and the battery cell body are arranged at an interval, and the current collecting plate is provided with a through hole and a pressure relief part; the pressure relief mechanism is arranged on the end cover, at least part of a pressure relief area of the pressure relief mechanism is opposite to the through hole, and the pressure relief part is used for allowing high-temperature flue gas to flow and pass to reach the pressure relief mechanism when thermal runaway occurs to the cylindrical battery monomers. According to the technical scheme, the problem that the non-directional pressure relief condition occurs during thermal runaway due to the fact that the opening area of the through hole of the collector plate of the cylindrical battery monomer is insufficient is solved.

Description

Technical Field

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

[0002] In related technologies, the ratio between the opening area of ​​the through hole of the current collector of a cylindrical battery cell and the area of ​​the pressure relief area of ​​the pressure relief mechanism is about 0.06, which indicates that the opening area of ​​the through hole of the current collector is insufficient.

[0003] When a cylindrical battery cell experiences thermal runaway, the high-temperature flue gas generated inside the cell needs to flow through the through-hole to reach the pressure relief mechanism, and then be ejected from the mechanism to the outside of the cell. However, due to the insufficient opening area of ​​the through-hole in the current collector, non-directional pressure relief can occur, affecting the safety of the cylindrical battery cell. Utility Model Content

[0004] The purpose of this application is to provide a cylindrical battery cell, a battery device, an energy storage device, and an electrical device, including but not limited to solving the problem that insufficient opening area of ​​the through hole in the current collector of the cylindrical battery cell leads to non-directional pressure relief during thermal runaway.

[0005] To achieve the above objectives, according to a first aspect of the embodiments of this application, a cylindrical battery cell is provided, comprising:

[0006] A cylindrical shell and at least one end cap, the end cap closing onto the open end of the cylindrical shell to form a receiving space;

[0007] An electrode assembly is housed in a housing space. The electrode assembly includes a battery cell body and tabs connected to the battery cell body.

[0008] The current collector is electrically connected to the electrode tab and located in the housing space. The current collector is spaced apart from the battery cell body. The current collector is provided with through holes and pressure relief parts.

[0009] A pressure relief mechanism is provided on the end cap. At least a portion of the pressure relief area of ​​the pressure relief mechanism is disposed opposite to the through hole. Furthermore, the pressure relief section is used to allow high-temperature flue gas to flow through and reach the pressure relief mechanism when thermal runaway occurs in a cylindrical battery cell.

[0010] The embodiments of this application provide a pressure relief section added to the current collector of the cylindrical battery cell in addition to the through hole. In the event of thermal runaway in the cylindrical battery cell, the pressure relief section allows high-temperature flue gas inside the cell to flow through and reach the pressure relief mechanism. Thus, the pressure relief section, together with the through hole, allows for sufficient flow area for the high-temperature flue gas, improving the efficiency of the high-temperature flue gas flowing through the current collector to the pressure relief mechanism. Furthermore, the rapid flow of high-temperature flue gas through the current collector to the pressure relief mechanism actuates and opens the mechanism, thereby releasing the high-temperature flue gas inside the cylindrical battery cell. This ensures directional pressure relief of the high-temperature flue gas and improves the safety of the cylindrical battery cell in use.

[0011] In some embodiments of this application, the pressure relief area of ​​the pressure relief mechanism is positioned directly opposite the through hole. This allows the high-temperature flue gas flowing through the collector to be concentrated and compressed onto the pressure relief mechanism, rapidly actuating it to open and quickly release the high-temperature flue gas inside the cylindrical battery cell.

[0012] In some embodiments of this application, the pressure relief section includes a fractured structure surrounding the through hole. High-temperature flue gas compresses and breaks the fractured structure, increasing the passage area on the collector plate that allows high-temperature flue gas to flow through to the pressure relief mechanism compared to the passage area of ​​the through hole. This allows the high-temperature flue gas to flow directionally towards the pressure relief mechanism, rapidly actuating and opening it. This enables rapid release of high-temperature flue gas from inside the cylindrical battery cell, ensuring directional pressure relief, improving release efficiency, and enhancing the safety of the cylindrical battery cell.

[0013] In some embodiments of this application, the thickness of the easily cracked structure is H1, and the thickness of the manifold is H2, wherein 0.2H2≤H1≤0.5H2. The relatively thin easily cracked structure will reach the stress limit first and break, thereby increasing the passage area of ​​the manifold that allows high-temperature flue gas to flow through.

[0014] In some embodiments of this application, the easily crackable structure is configured as a continuous circular groove structure around the through hole, which saves materials and takes into account economic rationality.

[0015] In some embodiments of this application, the crackable structure includes multiple crackable segments, which surround the through hole and are spaced apart, thus helping to improve the overall mechanical strength of the manifold.

[0016] In some embodiments of this application, the easily fractured segment is an arc-shaped segment or a straight segment.

[0017] In some embodiments of this application, the pressure relief section includes multiple flow holes surrounding the through hole. When thermal runaway occurs in a cylindrical battery cell, high-temperature flue gas can simultaneously flow through the through hole and the multiple flow holes to reach the pressure relief mechanism. This allows the high-temperature flue gas to flow directionally towards the pressure relief mechanism, rapidly actuating and opening it. This enables rapid response and release of the high-temperature flue gas inside the cylindrical battery cell, ensuring directional pressure relief, improving release efficiency, and enhancing the safety of the cylindrical battery cell.

[0018] In some embodiments of this application, along the axial direction of the cylindrical battery cell, the sum of the projected areas of the multiple flow holes and the through holes is S1, and the projected area of ​​the pressure relief region of the pressure relief mechanism is S2, wherein 0.5 ≤ S1 / S2 ≤ 1.2. This allows the high-temperature flue gas to flow directionally to the pressure relief mechanism, and quickly actuates the pressure relief mechanism to open, achieving rapid response and release of the high-temperature flue gas inside the cylindrical battery cell, ensuring directional pressure relief of the high-temperature flue gas.

[0019] In some embodiments of this application, the cylindrical battery cell includes two end caps, two current collectors and two pressure relief mechanisms. The two pressure relief mechanisms are respectively disposed on the two end caps, and both ends of the cell body are connected to tabs that are electrically connected to the two current collectors respectively.

[0020] According to a second aspect of the embodiments of this application, a battery device is provided. The battery device includes a cylindrical battery cell as described above, the cylindrical battery cell being used to store or provide electrical energy.

[0021] According to a third aspect of the embodiments of this application, an energy storage device is provided. Wherein:

[0022] The energy storage device includes cylindrical battery cells as described above, which are used to store or provide electrical energy.

[0023] Alternatively, the energy storage device may include a battery device as described above, which is used to store or provide electrical energy.

[0024] According to a fourth aspect of an embodiment of this application, an electrical appliance is provided. The electrical appliance includes an electrical load; and,

[0025] The electrical equipment also includes multiple cylindrical battery cells as described above, and the electrical load is electrically connected to the multiple cylindrical battery cells.

[0026] Alternatively, the electrical equipment may also include a battery device as described above, with the electrical load electrically connected to the battery device;

[0027] 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

[0028] 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.

[0029] Figure 1 This is a schematic diagram of the assembly structure of a cylindrical battery cell according to an embodiment of this application;

[0030] Figure 2 for Figure 1 An exploded view of a cylindrical battery cell is shown.

[0031] Figure 3 This is a front view schematic diagram of a current collector of a cylindrical battery cell according to an embodiment of this application;

[0032] Figure 4 for Figure 3 A cross-sectional view along the AA direction;

[0033] Figure 5 for Figure 3 Another sectional view along the AA direction;

[0034] Figure 6 This is a front view schematic diagram of another current collector of a cylindrical battery cell according to an embodiment of this application;

[0035] Figure 7 This is a front view schematic diagram of another current collector of a cylindrical battery cell according to an embodiment of this application;

[0036] Figure 8 This is a schematic diagram of the assembly structure of another cylindrical battery cell according to an embodiment of this application;

[0037] Figure 9 This is an exploded view of a battery device according to an embodiment of this application;

[0038] Figure 10 This is a schematic diagram of the structure of an energy storage device according to an embodiment of this application;

[0039] Figure 11 This is a schematic diagram of the structure of an electrical device according to an embodiment of this application.

[0040] The figures in the diagram are labeled as follows:

[0041] 100. Cylindrical battery cell;

[0042] 10. Cylindrical shell; 11. Open end; 12. Accommodating space;

[0043] 20. End cap; 21. Pole post structure;

[0044] 30. Electrode assembly; 31. Battery cell body; 32. Tab;

[0045] 40. Manifold; 41. Through hole; 42. Pressure relief section; 421. Fragile structure; 422. Fragile section; 423. Flow hole;

[0046] 50. Pressure relief mechanism;

[0047] 200. Battery assembly; 201. Box body; 202. Box cover; 203. Assembly space;

[0048] 300. Energy storage device; 301. Cabinet;

[0049] 400. Electrical equipment; 410. Electrical load; 420. Control device; 430. Chassis; 440. Wheel. Detailed Implementation

[0050] 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.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] 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.

[0055] In related technologies, the ratio between the opening area of ​​the through-hole in the current collector of a cylindrical battery cell and the area of ​​the pressure relief region of the pressure relief mechanism is approximately 0.06, indicating insufficient opening area of ​​the through-hole in the current collector. When thermal runaway occurs in a cylindrical battery cell, the high-temperature flue gas generated inside the cell needs to flow through the through-hole to reach the pressure relief mechanism and then be ejected from the cell. However, due to the insufficient opening area of ​​the through-hole in the current collector, the high-temperature flue gas cannot flow through it quickly and may even be blocked by electrode fragments from the battery cell, further hindering its flow. This can lead to non-directional pressure relief of the high-temperature flue gas, affecting the safety of the cylindrical battery cell.

[0056] "Non-directional pressure relief" refers to the phenomenon where, during thermal runaway in a cylindrical battery cell, the internal temperature and pressure rise rapidly, causing high-temperature fumes and heat to be released through unintended pathways. Non-directional pressure relief is the opposite of directional pressure relief. Directional pressure relief involves releasing pressure through a designed, predetermined path, such as a safety valve or pressure relief port. Therefore, non-directional pressure relief differs from well-designed directional pressure relief. Non-directional pressure relief, by releasing pressure through unintended pathways, can potentially lead to battery casing rupture, the ejection of flames or high-temperature gases, and even a fire.

[0057] The causes of non-directional pressure relief may include: 1. Design defects: The casing or safety valve of the cylindrical battery cell is poorly designed and cannot effectively guide the release of internal pressure; 2. Excessive thermal runaway intensity: The internal reaction of the cylindrical battery cell is too violent, and the heat and pressure generated exceed the designed pressure relief capacity; 3. External constraints: The cylindrical battery cell is installed in a confined space, which may obstruct the normal pressure relief path; etc.

[0058] In summary, the consequences of non-directional pressure relief can be quite severe. For example, in confined spaces, non-directional pressure relief can lead to the ejection of high-temperature flue gas and particulate matter, triggering flashover, and even causing thermal runaway propagation among multiple cylindrical battery cells in the battery device. Therefore, non-directional pressure relief should be prevented as much as possible.

[0059] Based on the above considerations, embodiments of this application provide a cylindrical battery cell, and this cylindrical battery cell is used to assemble and produce battery devices, energy storage devices, and electrical equipment. Specifically, the current collector of the cylindrical battery cell is supplemented with a pressure relief section in addition to the through-hole. In the event of thermal runaway in the cylindrical battery cell, the pressure relief section allows high-temperature flue gas inside the cell to flow through and reach the pressure relief mechanism. Thus, the pressure relief section, together with the through-hole, provides sufficient passage area for high-temperature flue gas flow, improving the efficiency of high-temperature flue gas flow through the current collector to the pressure relief mechanism. Furthermore, the high-temperature flue gas rapidly flowing through the current collector to the pressure relief mechanism actuates and opens, thereby releasing the high-temperature flue gas inside the cylindrical battery cell, ensuring directional pressure relief of the high-temperature flue gas, and improving the safety of the cylindrical battery cell in use.

[0060] 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.

[0061] According to a first aspect of the embodiments of this application, embodiments of this application provide a cylindrical battery cell 100. For example... Figures 1 to 8As shown, the cylindrical battery cell 100 includes a cylindrical housing 10, an electrode assembly 30, a current collector 40, a pressure relief mechanism 50, and at least one end cap 20. The end cap 20 closes to the open end 11 of the cylindrical housing 10 to form a receiving space 12, in which the electrode assembly 30 is received. The electrode assembly 30 includes a cell body 31 and tabs 32 connected to the cell body 31. The current collector 40 is electrically connected to the tabs 32 and located within the receiving space 12. The current collector 40 is also electrically connected to the electrode post structure 21 disposed on the end cap 20. The current collector 40 is spaced apart from the cell body 31. The current collector 40 has a through hole 41 and a pressure relief section 42. The pressure relief section 42 may be circumferentially surrounding the through hole 41 or randomly distributed on the current collector 40, etc., as long as it can allow high-temperature flue gas to flow through and reach the pressure relief mechanism 50 when the cylindrical battery cell 100 experiences thermal runaway. Furthermore, the pressure relief mechanism 50 is disposed on the end cap 20, and at least a portion of the pressure relief area of ​​the pressure relief mechanism 50 is disposed opposite to the through hole 41. The pressure relief part 42 is used to allow high-temperature flue gas to flow through and reach the pressure relief mechanism 50 when thermal runaway occurs in the cylindrical battery cell 100.

[0062] The embodiment of this application provides a pressure relief section 42 added to the collector plate 40 of the cylindrical battery cell 100 based on the through hole 41. When thermal runaway occurs in the cylindrical battery cell 100, the pressure relief section 42 allows high-temperature flue gas inside the cylindrical battery cell 100 to flow through and reach the pressure relief mechanism 50. Thus, the pressure relief section 42, together with the through hole 41, allows high-temperature flue gas to flow through, ensuring sufficient passage area for the high-temperature flue gas and improving the efficiency of the high-temperature flue gas flowing through the collector plate 40 to reach the pressure relief mechanism 50. Furthermore, the high-temperature flue gas rapidly flowing through the collector plate 40 to reach the pressure relief mechanism 50 actuates and opens, thereby releasing the high-temperature flue gas inside the cylindrical battery cell 100, ensuring directional pressure relief of the high-temperature flue gas, and improving the safety of the cylindrical battery cell 100 in use.

[0063] The current collector 40 is spaced apart from the cell body 31, so that the through holes 41 of the current collector 40, in addition to allowing high-pressure flue gas to flow through to the pressure relief mechanism 50 when thermal runaway occurs in the cylindrical battery cell 100, also allow electrolyte to flow through the through holes 41 to the electrode assembly 30 during the assembly and production of the cylindrical battery cell 100, thereby wetting the electrode plates of the electrode assembly 30 with electrolyte. This ensures that a stable electrochemical reaction occurs in the cylindrical battery cell 100 during charging and discharging.

[0064] The pressure relief mechanism 50 refers to a component or part that is activated to release internal pressure when the internal pressure or temperature of the cylindrical battery cell 100 reaches a predetermined threshold. "Activation" means that the pressure relief mechanism 50 performs an action, thereby releasing the internal pressure and temperature of the cylindrical battery cell 100. The action of the pressure relief mechanism 50 may include, but is not limited to, at least a portion of the pressure relief mechanism 50 rupturing, tearing, or melting. After activation, the high-temperature flue gas inside the cylindrical battery cell 100 will be discharged outward from the pressure relief mechanism 50. The predetermined threshold can be adjusted according to different design requirements. The predetermined threshold may depend on one or more of the materials of the positive electrode, negative electrode, separator, and electrolyte in the electrode assembly 30 of the cylindrical battery cell 100. The pressure relief mechanism 50 may employ elements or components that are sensitive to pressure or temperature. That is, when the internal pressure or temperature of the cylindrical battery cell 100 reaches a predetermined threshold, the pressure relief mechanism 50 is activated to form a channel for releasing internal pressure (i.e., the pressure relief area of ​​the pressure relief mechanism 50).

[0065] In some embodiments of the cylindrical battery cell 100 of this application, the pressure relief region of the pressure relief mechanism 50 is directly opposite to the through hole 41, and along the axial direction of the cylindrical battery cell 100, the projected area of ​​the flow surface of the through hole 41 is smaller than the projected area of ​​the pressure relief region of the pressure relief mechanism 50. In this case, the projection of the flow surface of the through hole 41 is located within the projection of the pressure relief region of the pressure relief mechanism 50. When the cylindrical battery cell 100 experiences thermal runaway, high-temperature flue gas not only flows through the through hole 41 to reach the pressure relief mechanism 50, but the pressure relief section 42 also allows the high-temperature flue gas to flow through. Since the through hole 41 is positioned directly opposite the pressure relief area of ​​the pressure relief mechanism 50, and the pressure relief section 42 simultaneously allows high-temperature flue gas to flow through and reach the pressure relief mechanism 50, the high-temperature flue gas flowing through the collector plate 40 can almost concentrate and compress onto the pressure relief mechanism 50, thereby quickly actuating and opening the pressure relief mechanism 50. This enables rapid response and release of the high-temperature flue gas inside the cylindrical battery cell 100, ensuring directional pressure relief of the high-temperature flue gas, improving release efficiency, and enhancing the safety of the cylindrical battery cell 100 in use.

[0066] In some embodiments of this application, such as Figures 3 to 6As shown, the pressure relief section 42 includes a fractured structure 421 surrounding the through hole 41. In this embodiment, when the cylindrical battery cell 100 experiences thermal runaway, while the high-temperature flue gas flows through the through hole 41, it also compresses the fractured structure 421 and conducts heat to it. Under the action of compression and / or heat conduction, the fractured structure 421 breaks, allowing the high-temperature flue gas to flow to the pressure relief mechanism 50. That is, the high-temperature flue gas compresses and breaks the fractured structure 421, increasing the passage area on the collector plate 40 that allows the high-temperature flue gas to flow to the pressure relief mechanism 50 compared to the passage area of ​​the through hole 41. This allows the high-temperature flue gas to flow directionally to the pressure relief mechanism 50, quickly actuating the pressure relief mechanism 50 to open, achieving rapid response and release of the high-temperature flue gas inside the cylindrical battery cell 100, ensuring directional pressure relief of the high-temperature flue gas, improving release efficiency, and enhancing the safety of the cylindrical battery cell 100. Furthermore, when the cylindrical battery cell 100 is charging and discharging normally, the crackable structure 421 remains completely sealed, so as not to lose or to minimize the loss of the current carrying capacity of the current collector 40.

[0067] like Figure 4 and Figure 5 As shown, the thickness of the easily fractured structure 421 is H1, and the thickness of the current collector 40 is H2, where 0.2H2≤H1≤0.5H2. When the cylindrical battery cell 100 experiences thermal runaway, the entire current collector 40 will be subjected to the compression of high-temperature flue gas. The relatively thin easily fractured structure 421 will reach its stress limit first and break, thereby increasing the passage area of ​​the current collector 40 that allows high-temperature flue gas to flow through. This allows the high-temperature flue gas to flow directionally towards the pressure relief mechanism 50, quickly actuating and opening the pressure relief mechanism 50, achieving rapid response and release of the high-temperature flue gas inside the cylindrical battery cell 100, ensuring directional pressure relief of the high-temperature flue gas, improving release efficiency, and enhancing the safety of the cylindrical battery cell 100 in use.

[0068] like Figure 4 As shown, in some embodiments of this application, the cross-sectional profile of the easily crackable structure 421 on the manifold 40 is designed as a rectangular groove to achieve an easily crackable effect. Alternatively, as... Figure 5 As shown, in some other embodiments of this application, the cross-sectional profile of the easily crackable structure 421 on the collector plate 40 is designed as a triangular groove to achieve an easily crackable effect. In fact, any structure that reduces the thickness of the easily crackable structure 421, making it thin, and can achieve an easily crackable effect when subjected to high-temperature flue gas compression, is acceptable and is not limited here.

[0069] In some embodiments of this application, such as Figure 3As shown, the easily crackable structure 421 is configured as a continuous circular groove structure surrounding the through hole 41. While ensuring that the easily crackable structure 421 can achieve the easily crackable effect, the continuous circular easily crackable structure 421 can reduce the overall material usage of the manifold 40, save materials, and take into account economic rationality.

[0070] In other embodiments of this application, such as Figure 6 As shown, the easily crackable structure 421 includes multiple easily crackable segments 422, which surround the through hole 41 and are spaced apart. While ensuring that the easily crackable structure 421 can achieve the easily crackable effect, the easily crackable structure 421 composed of multiple spaced easily crackable segments 422 helps to improve the overall mechanical strength of the manifold 40.

[0071] In some embodiments of this application, the easily breakable segment 422 is, but is not limited to, an arc-shaped segment or a straight segment. Of course, the easily breakable segment 422 can also be a serpentine shape, a wavy shape, etc., and is not limited here.

[0072] In some embodiments of the cylindrical battery cell 100 of this application, such as Figure 7 As shown, the pressure relief section 42 includes multiple flow holes 423 surrounding the through hole 41. During the assembly and production of the cylindrical battery cell 100, when injecting electrolyte, the electrolyte can flow into the electrode assembly 30 not only through the through hole 41 but also through the multiple flow holes 423, thus wetting the electrode plates of the electrode assembly 30. This ensures a stable electrochemical reaction during the charging and discharging of the cylindrical battery cell 100. When the cylindrical battery cell 100 experiences thermal runaway, high-temperature flue gas can simultaneously flow through the through hole 41 and the multiple flow holes 423 to reach the pressure relief mechanism 50. This allows the high-temperature flue gas to flow directionally towards the pressure relief mechanism 50, rapidly actuating and opening it. This enables a rapid response to release the high-temperature flue gas inside the cylindrical battery cell 100, ensuring directional pressure relief, improving release efficiency, and enhancing the safety of the cylindrical battery cell 100.

[0073] In some embodiments of this application, along the axial direction of the cylindrical battery cell 100, the sum of the projected area of ​​the plurality of flow holes 423 and the projected area of ​​the through hole 41 is S1, and the projected area of ​​the pressure relief area of ​​the pressure relief mechanism 50 is S2, wherein 0.5≤S1 / S2≤1.2. Thus, compared to the through-hole design of the current collector of the cylindrical battery cell in related technologies, the current collector 40 of the cylindrical battery cell 100 in this embodiment of the application adds multiple flow holes 423 on the basis of the through hole 41, which increases the flow area of ​​high-temperature flue gas when thermal runaway occurs in the cylindrical battery cell 100. The ratio between the flow area of ​​the current collector 40 and the area of ​​the pressure relief area of ​​the pressure relief mechanism 50 is in the range of 0.5-1.2, that is, 0.5≤S1 / S2≤1.2. The high-temperature flue gas achieves directional flow to the pressure relief mechanism 50 and quickly actuates the pressure relief mechanism 50 to open, realizing rapid response to release the high-temperature flue gas inside the cylindrical battery cell 100, ensuring directional pressure relief of the high-temperature flue gas, improving the release efficiency, and improving the safety of the cylindrical battery cell 100 in use.

[0074] In some embodiments of this application, the collector plate 40 may only have through holes 41, and the ratio between the through area of ​​the through hole 41 and the area of ​​the pressure relief region of the pressure relief mechanism 50 satisfies 0.5≤S1 / S2≤1.2. Furthermore, the pressure relief region of the pressure relief mechanism 50 is directly opposite the through hole 41. That is, the pressure relief part 42 is omitted from the collector plate 40 in this embodiment. Also, along the axial direction of the cylindrical battery cell 100, the projected area of ​​the flow surface of the through hole 41 and the projected area of ​​the pressure relief region of the pressure relief mechanism 50 may be equal; in this case, the projection of the flow surface of the through hole 41 coincides with the projection of the pressure relief region of the pressure relief mechanism 50. Alternatively, along the axial direction of the cylindrical battery cell 100, the projected area of ​​the flow surface of the through hole 41 may be smaller than the projected area of ​​the pressure relief region of the pressure relief mechanism 50; in this case, the projection of the flow surface of the through hole 41 lies within the projection of the pressure relief region of the pressure relief mechanism 50. Alternatively, along the axial direction of the cylindrical battery cell 100, the projected area of ​​the flow surface of the through hole 41 is greater than the projected area of ​​the pressure relief area of ​​the pressure relief mechanism 50. In this case, the projection of the pressure relief area of ​​the pressure relief mechanism 50 is located within the projection of the flow surface of the through hole 41.

[0075] During the experimental verification, the area of ​​the pressure relief region of the pressure relief mechanism 50 was taken as a fixed value S2 = 420 mm. 2 Discharge experiments were conducted on different manifolds 40 with different flow areas S1. The experimental results are shown in the table below.

[0076]

[0077] (1) When 0.5≤S1 / S2≤1.2, when the cylindrical battery cell 100 experiences thermal runaway, normal pressure relief can be achieved, ensuring that the cylindrical battery cell 100 does not experience blockage of the collector 40 and cause extreme events such as explosion.

[0078] Furthermore, when 0.5≤S1 / S2<0.8, stable and normal pressure relief can be achieved when thermal runaway occurs in the cylindrical battery cell 100.

[0079] Furthermore, when 0.8 < S1 / S2 ≤ 1.2, this is the optimal range of design parameters. When the cylindrical battery cell 100 experiences thermal runaway, it can not only achieve stable directional pressure relief, but also prevent the current collector 40 from becoming clogged.

[0080] (2) When S1 / S2 < 0.5, when the cylindrical battery cell 100 experiences thermal runaway, the current collector 40 is at risk of being blocked. At this time, due to the small passage area of ​​the current collector 40, insufficient pressure relief will result in non-directional pressure relief.

[0081] (3) When S1 / S2>1.2, when the cylindrical battery cell 100 experiences thermal runaway, the pass-through area of ​​the current collector 40 is too large. The large-volume electrode fragments carried by the high-temperature flue gas reach the pressure relief mechanism 50 through the current collector 40. However, these large-volume electrode fragments will not be ejected from the pressure relief mechanism 50, but will block the pressure relief mechanism 50.

[0082] Therefore, the ratio between the through area of ​​the collector plate 40 and the area of ​​the pressure relief area of ​​the pressure relief mechanism 50 is in the range of 0.5-1.2, that is, 0.5≤S1 / S2≤1.2. This allows the high-temperature flue gas to flow directionally to the pressure relief mechanism 50 and quickly actuate the pressure relief mechanism 50 to open, thereby achieving rapid response and release of the high-temperature flue gas inside the cylindrical battery cell 100. This ensures that the high-temperature flue gas is depressurized directionally, improves the release efficiency, and enhances the safety of the cylindrical battery cell 100 in use.

[0083] In some embodiments of the cylindrical battery cell 100 of this application, such as Figure 2As shown, the cylindrical battery cell 100 includes two end caps 20, two current collectors 40, and two pressure relief mechanisms 50. The two pressure relief mechanisms 50 are respectively disposed on the two end caps 20. Both ends of the cell body 31 are connected to tabs 32 that are electrically connected to the two current collectors 40. That is to say, for the cylindrical battery cell 100 with electrodes at both ends and pressure relief mechanisms 50 at both ends, it is assembled with corresponding two current collectors 40. Thus, when thermal runaway occurs, the two current collectors 40 can increase the passage area for high-temperature flue gas to flow through, so that the high-temperature flue gas can flow directionally to the pressure relief mechanism 50, quickly actuating the pressure relief mechanism 50 to open, realizing rapid response to release the high-temperature flue gas inside the cylindrical battery cell 100, ensuring directional pressure relief of the high-temperature flue gas, improving the release efficiency, and improving the safety of the cylindrical battery cell 100 in use.

[0084] Of course, in other embodiments of this application, such as Figure 8 As shown, for a cylindrical battery cell 100 with an electrode at one end and a pressure relief mechanism 50 at only one end, it is assembled with a corresponding current collector 40. In the event of thermal runaway, the passage area for high-temperature flue gas to flow through can be increased, allowing the high-temperature flue gas to flow directionally to the pressure relief mechanism 50, which will quickly actuate and open, thereby achieving rapid response and release of high-temperature flue gas inside the cylindrical battery cell 100. This ensures that the high-temperature flue gas is released in a directional manner, improves the release efficiency, and enhances the safety of the cylindrical battery cell 100 in use.

[0085] In the embodiments of this application, the cylindrical battery cell 100 can be a secondary battery. A secondary battery refers to a cylindrical battery cell 100 that can be recharged after discharge to activate the active materials and continue to be used. The cylindrical 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.

[0086] According to a second aspect of the embodiments of this application, embodiments of this application also provide a battery device 200, such as... Figure 9 As shown, the battery device 200 includes a main body 201, a cover 202, and multiple cylindrical battery cells 100 as described above. The cover 202 closes onto the open end of the main body 201, forming an assembly space 203. The multiple cylindrical battery cells 100 are arrayed and assembled within the assembly space 203. The cylindrical battery cells 100 are used for storing electrical energy or supplying power.

[0087] 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 a plurality of cylindrical battery cells 100 as described above, that is, the energy storage device 300 uses a plurality of cylindrical battery cells 100 connected in series, parallel, or mixed, such that these cylindrical battery cells 100 are used to store electrical energy or provide electrical energy.

[0088] 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.

[0089] like Figure 10 As 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.

[0090] 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.

[0091] As an example, the thermal management module may include a liquid cooling unit that supplies coolant to each cylindrical battery cell 100 or each battery assembly 200 via pipelines for regulating the temperature of the cylindrical battery cell 100.

[0092] As an example, the main control module can serve as a battery management unit for multiple cylindrical 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 cylindrical battery cells 100 or multiple battery devices 200. For example, it can control the charging and discharging current and voltage of the multiple cylindrical 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.

[0093] 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.

[0094] 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.

[0095] 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.

[0096] 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.

[0097] 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.

[0098] 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.

[0099] 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.

[0100] Alternatively, in some other embodiments of this application, the electrical device 400 further includes a plurality of cylindrical battery cells 100 as described above. That is, the electrical device 400 uses a plurality of cylindrical battery cells 100 connected in series, parallel, or in a mixed configuration, and the electrical load 410 is electrically connected to the plurality of cylindrical battery cells 100. The plurality of cylindrical battery cells 100 are used to store electrical energy, or the plurality of cylindrical battery cells 100 are used to provide electrical energy to the electrical load 410, thereby enabling the electrical load 410 to operate normally.

[0101] Among them, the electrical equipment 400 is an electric vehicle, and it is assembled using a battery device 200, such as Figure 11 As 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.

[0102] 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 cylindrical battery cell, characterized by, The cylindrical battery cell comprises: a cylindrical shell and at least one end cover, the end cover covering an open end of the cylindrical shell to form a containing space; an electrode assembly contained in the containing space, the electrode assembly comprising an electrode core body and a tab connected to the electrode core body; a current collector plate electrically connected to the tab and located in the containing space, the current collector plate being spaced apart from the electrode core body, the current collector plate being provided with a through hole and a pressure relief portion; a pressure relief mechanism arranged on the end cover, at least part of the pressure relief area of the pressure relief mechanism being arranged opposite the through hole, and the pressure relief portion being used for the high-temperature smoke to flow through to the pressure relief mechanism when the cylindrical battery cell undergoes thermal runaway.

2. The cylindrical battery cell according to claim 1, wherein the pressure relief area of the pressure relief mechanism is arranged opposite the through hole.

3. The cylindrical battery cell according to claim 1, wherein the pressure relief portion comprises a breakable structure, and the breakable structure surrounds the through hole.

4. The cylindrical battery cell according to claim 3, wherein the thickness of the breakable structure is H1, the thickness of the current collector plate is H2, and 0.2H2≤H1≤0.5H2.

5. The cylindrical battery cell according to claim 4, wherein the breakable structure is arranged as a continuous circular groove structure surrounding the through hole.

6. The cylindrical battery cell according to claim 4, wherein the breakable structure comprises a plurality of breakable segments, and the plurality of breakable segments are arranged around the through hole and are spaced apart.

7. The cylindrical battery cell according to claim 6, wherein the breakable segments are arc-shaped segments or straight segments.

8. The cylindrical battery cell according to claim 4, wherein the pressure relief portion comprises a plurality of flow holes, and the plurality of flow holes surround the through hole.

9. The cylindrical battery cell according to claim 8, wherein in the axial direction of the cylindrical battery cell, the sum of the projection area of the plurality of flow holes and the projection area of the through hole is S1, and the projection area of the pressure relief area of the pressure relief mechanism is S2, wherein 0.5≤S1 / S2≤1.

2.

10. The cylindrical battery cell according to any one of claims 1-9, wherein the cylindrical battery cell comprises two end covers, two current collector plates, and two pressure relief mechanisms, the two pressure relief mechanisms are arranged on the two end covers respectively, and the tabs electrically connected to the two current collector plates are connected to the two ends of the electrode core body respectively.

11. A battery device characterized by comprising: The cylindrical battery cell according to any one of claims 1-10 is used for storing or providing electric energy.

12. An energy storage device, comprising the cylindrical battery cell according to any one of claims 1-10, wherein the cylindrical battery cell is used for storing or providing electric energy; or the energy storage device comprises the battery device according to claim 11, wherein the battery device is used for storing or providing electric energy. The energy storage device comprises an electric load. ​ 13. An electrical device, characterized by ​ The electric device further comprises a plurality of cylindrical battery cells as claimed in any one of claims 1-10, and the electric load is electrically connected with the plurality of cylindrical battery cells. Alternatively, the electric device further comprises a battery device as claimed in claim 11, and the electric load is electrically connected with the battery device. Alternatively, the electric device further comprises an energy storage device as claimed in claim 12, and the electric load is electrically connected with the energy storage device.

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