A battery cell, a battery device, and an electrical device.

Abstract

This disclosure provides a battery cell, a battery device, and an electrical device, belonging to the field of battery technology. The battery cell includes a casing, electrode terminals, electrode assemblies, a pressure relief mechanism, and an insulating component. One of the casing walls is a predetermined casing wall. The electrode terminals are disposed within the casing. The electrode assemblies are located inside the casing and electrically connected to the electrode terminals. The predetermined casing wall and the electrode assemblies are arranged in a first direction. The pressure relief mechanism is disposed within the predetermined casing wall. The insulating component is located between the predetermined casing wall and the electrode assemblies. The insulating component has multiple vent holes and includes an interconnected main body and a boss. The boss is located between the main body and the electrode assemblies along the first direction. The vent hole formed in the main body is a first vent hole. Along the first direction, the projection area of ​​the first vent hole is located within the projection area of ​​the pressure relief mechanism. The venting capacity of the battery cell is improved by providing the first vent hole.

Description

Technical Field

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

[0002] Batteries are being used more and more widely in daily life and industry. For example, new energy vehicles equipped with batteries are already widely used. In addition, batteries are increasingly being used in the field of energy storage.

[0003] In related technologies, the venting capacity of individual battery cells is limited. Utility Model Content

[0004] To address the aforementioned technical problems, this disclosure provides a battery cell, a battery device, and an electrical device to improve the venting capacity of the battery cell.

[0005] This application is achieved through the following technical solution.

[0006] This disclosure provides a single battery cell, comprising:

[0007] The outer casing, wherein one of the casing walls is a pre-defined casing wall;

[0008] Electrode terminals are disposed on the housing;

[0009] An electrode assembly is located inside the housing and electrically connected to the electrode terminals, and the arrangement direction of the preset housing wall and the electrode assembly is a first direction;

[0010] A pressure relief mechanism is provided on the preset shell wall;

[0011] An insulating element is located between the preset shell wall and the electrode assembly. The insulating element has multiple vent holes. The insulating element includes a main body and a boss connected to each other. The boss is located between the main body and the electrode assembly along the first direction. The vent hole formed in the main body is a first vent hole. Along the first direction, the projection area of ​​the first vent hole is located within the projection area of ​​the pressure relief mechanism.

[0012] In this embodiment of the present disclosure, the boss of the insulating member is connected to the main body. The boss is located between the main body and the electrode assembly along the first direction. The boss can abut against the electrode assembly to suppress the electrode assembly from moving toward the main body under the action of the thermal runaway ejection. This allows the main body and the electrode assembly to maintain a better distance, reducing the possibility that the first vent hole on the main body will be blocked by the electrode assembly. This allows the ejection of gas and other ejection generated by the electrode assembly during thermal runaway to pass through the first vent hole better. Since the projection area of ​​the first vent hole along the first direction is located within the projection area of ​​the pressure relief mechanism along the first direction, the ejection of gas and other ejection generated by thermal runaway discharged from the first vent hole can be discharged from the pressure relief mechanism more smoothly, thus achieving better pressure relief. The main body is provided with a first vent hole, and the projection area of ​​the first vent hole along the first direction is located in the projection area of ​​the pressure relief mechanism along the first direction. By venting the gas and other thermal runaway ejected materials through the first vent hole, the area where the projection area of ​​the main body along the first direction overlaps with the projection area of ​​the pressure relief mechanism along the first direction can be fully utilized to vent the gas and other thermal runaway ejected materials, thereby improving the venting capacity of the battery cell and enabling better venting of the gas and other thermal runaway ejected materials during the thermal runaway process of the battery cell.

[0013] In some embodiments, the battery cell has an injection hole penetrating the preset shell wall and the insulating member, the injection hole and the pressure relief mechanism are arranged in the second direction, the second direction is intersected with the first direction, and part of the first vent hole is located on the side of the boss facing the injection hole along the second direction.

[0014] In this embodiment, a portion of the first vent is located on the side of the boss facing the injection port along the second direction. The boss does not completely cover the side of the pressure relief mechanism facing the injection port along the second direction, and there is a considerable distance between the boss and the injection port. Even if the electrolyte is injected into the housing through the injection port in a diffuse manner, the large distance between the boss and the injection port reduces the possibility of the electrolyte spreading and adhering to the boss, allowing the electrolyte injected into the housing through the injection port to flow as far as possible towards the electrode assembly to wet the electrode assembly.

[0015] In some embodiments, the electrode assembly has a flat region, and the boss is disposed across opposite sides of the pressure relief mechanism along the third direction, which is arranged to intersect the first direction and the second direction, respectively.

[0016] In this embodiment of the disclosure, the injection hole restricts the arrangement space of the boss in the second direction, while the spatial arrangement of the boss in the third direction is not greatly restricted. The boss is arranged across the opposite sides of the pressure relief mechanism along the third direction, so that the boss has a large contact surface when it abuts against the electrode assembly, which is beneficial to suppress the movement of the electrode assembly along the first direction.

[0017] In some embodiments, a portion of the first vent hole is located on the side of the boss away from the injection hole along the second direction.

[0018] In this embodiment, the area where the projection area of ​​the main body on both sides of the boss along the first direction overlaps with the projection area of ​​the pressure relief mechanism along the first direction can be fully utilized for venting, thereby improving the venting capacity of the battery cell.

[0019] In some embodiments, the boss has an exhaust chamber, the projection area of ​​the exhaust chamber along the first direction at least partially overlaps with the projection area of ​​the pressure relief mechanism along the first direction, the chamber walls on opposite sides along the second direction are first walls, the exhaust holes formed on the first walls are second exhaust holes communicating with the exhaust chamber, and the first wall of the exhaust chamber facing the injection hole has the second exhaust hole.

[0020] In this embodiment, the first wall of the venting chamber facing the injection hole has a second vent. Even when the boss abuts against the electrode assembly along the first direction, thermally runaway ejected materials such as gas can still enter the venting chamber through the second vent on the first wall and be discharged through the pressure relief mechanism, which facilitates better venting and improves the venting capacity of the battery cell. The venting chamber guides the thermally runaway ejected materials to converge in the venting chamber through the vent holes and then concentrates them out through the pressure relief mechanism, reducing the disorderly diffusion of the thermally runaway ejected materials. Since the boss has a first vent along the second direction facing the injection hole, the distance between the injection hole and the second vent is relatively large, reducing the possibility of electrolyte remaining in the venting chamber due to the electrolyte being diffusely injected into the casing from the injection hole entering the venting chamber through the second vent.

[0021] In some embodiments, the number of the second exhaust holes is at least one, and the projected area of ​​each second exhaust hole along the axial direction of the corresponding second exhaust hole is 14 mm. 2 ~22mm 2 .

[0022] In this embodiment, the projected area of ​​each second exhaust hole along the axial direction of the corresponding second exhaust hole is 14 mm. 2 ~22mm 2 This makes the area of ​​the second exhaust hole more suitable, which can both exhaust air well and give the first wall good structural strength.

[0023] In some embodiments, the number of second exhaust holes on at least one side of the first wall is multiple, and the directions in which the multiple second exhaust holes are arranged in sequence are respectively intersecting the first direction and the second direction. Along the direction in which the multiple second exhaust holes are arranged in sequence, the distance between two adjacent second exhaust holes is 2.5mm to 4mm.

[0024] In this embodiment, the distance between two adjacent second exhaust holes is 2.5mm to 4mm, which makes the distance between two adjacent second exhaust holes more suitable. While providing as many second exhaust holes as possible, the first wall still has good mechanical strength.

[0025] In some embodiments, the cavity wall of the exhaust chamber facing the electrode assembly along the first direction is a second wall, and the exhaust hole formed in the second wall is a third exhaust hole communicating with the exhaust chamber.

[0026] In this embodiment, since the third vent is formed on the second wall, even when the second wall abuts against the electrode assembly along the first direction, the gas in the part of the electrode assembly covered by the second wall can still be collected in the vent chamber through the third vent and discharged from the pressure relief mechanism, which is beneficial for the battery cell to vent better during thermal runaway. Furthermore, even if some electrolyte enters the vent chamber from the second vent on the first wall through the diffusion-shaped electrolyte injected into the casing from the injection hole, this portion of electrolyte can flow to the electrode assembly through the third vent on the second wall as much as possible, which helps to reduce electrolyte residue in the vent chamber and allows the electrolyte to better wet the electrode assembly.

[0027] In some embodiments, the maximum length of the projection area formed by the axial projection of each vent hole along the corresponding vent hole is a preset length, the preset length of the third vent hole is greater than the preset length of the second vent hole, and the preset length of the second vent hole is greater than the preset length of the first vent hole.

[0028] In this embodiment, the third vent is located on the second wall, which abuts against the electrode assembly to resist its movement along the first direction. The third vent has a relatively long preset length, and the second wall has a larger dimension in the corresponding direction, which facilitates better contact between the second wall and the electrode assembly to suppress its movement along the first direction. Due to the limited space for the boss, the space for the first wall is limited when the second wall is large. The preset length of the second vent is smaller than that of the third vent, which facilitates better arrangement of the second vent on the first wall. With the second and third vents arranged on the boss, most of the thermal runaway ejected material is discharged through the exhaust chamber via the second and third vents. The preset length of the second vent is greater than that of the first vent. Setting the preset length of the second vent longer facilitates better discharge of the thermal runaway ejected material from the second vent. Setting the preset length of the first vent shorter allows sufficient space for better arrangement of the first and second vents.

[0029] In some embodiments, the number of the third vent holes is at least one, and the projected area of ​​each third vent hole along the axial direction of the corresponding third vent hole is 40 mm. 2 ~50mm 2 .

[0030] In this embodiment, the area of ​​the third vent is suitable, which can effectively discharge thermally runaway ejected material and give the second wall good mechanical strength.

[0031] In some embodiments, there are multiple third exhaust holes, and the arrangement directions of the multiple third exhaust holes are respectively intersecting the first direction and the second direction. Along the arrangement directions of the multiple third exhaust holes, the distance between two adjacent third exhaust holes is 2.5mm to 4mm.

[0032] In this embodiment, the distance between two adjacent third vent holes is 2.5mm to 4mm, which makes the distance between two adjacent third vent holes more suitable. While providing as many third vent holes as possible, the second wall still has good mechanical strength.

[0033] In some embodiments, the second wall is located between the two first walls along the second direction, and the second wall is located on one side of the body facing the electrode assembly along the first direction. Each of the first walls is connected to the second wall and the corresponding body, respectively. Projected along the first direction, the projection area of ​​the second wall is arranged at intervals with the projection area of ​​the body.

[0034] In this embodiment, the inclined arrangement of the first walls on both sides is beneficial to increasing the area of ​​the first walls, and more second exhaust holes can be arranged on the first walls to facilitate the discharge of thermally runaway ejected material. The inclined first walls can guide the thermally runaway ejected material to the exhaust chamber for better collection and discharge.

[0035] In some embodiments, the second wall includes two sub-walls spaced apart along the second direction, at least one of the sub-walls being provided with the second vent hole, and the distance between the two sub-walls along the second direction being 1 mm to 5 mm.

[0036] In this embodiment, the distance between the two sub-walls is appropriate, and the thermal runaway ejecta can be better collected from between the two sub-walls into the exhaust chamber and discharged from the pressure relief mechanism, which is beneficial for the battery cells to better exhaust.

[0037] In some embodiments, the number of the first vent holes is at least one, and the projected area of ​​each first vent hole along the axial direction corresponding to the first vent hole is 10 mm. 2 ~14mm 2 .

[0038] In this embodiment of the present disclosure, the projected area of ​​each first exhaust hole along the axial direction of the corresponding first exhaust hole is 10 mm. 2 ~14mm 2 This ensures that the area of ​​the first vent is appropriate, allowing the first vent to effectively discharge thermally runaway ejected material while also giving the main body suitable mechanical strength.

[0039] In some embodiments, the projected area of ​​the pressure relief mechanism along the first direction is 780 mm². 2 ~950mm 2 ; and / or, the projected area of ​​each of the exhaust holes along the axial direction of the corresponding exhaust hole is a preset area, and the sum of the preset areas of all the exhaust holes is 1000 mm. 2 ~1200mm 2 .

[0040] In this embodiment, the projected area of ​​the pressure relief mechanism along the first direction is ~, making the area of ​​the pressure relief mechanism suitable. The pressure relief mechanism has a large area for pressure relief to facilitate the discharge of thermal runaway ejecta, and the housing on which the pressure relief mechanism is installed has suitable mechanical strength. The sum of the preset areas of all exhaust holes is 1000 mm². 2 ~1200mm 2 This ensures that the area of ​​the vent is suitable, allowing it to effectively discharge thermally runaway ejected material, while also ensuring that the mechanical strength of the insulating component with the vent is appropriate.

[0041] In some embodiments, the projection area of ​​the boss is at least partially located within the projection area of ​​the pressure relief mechanism.

[0042] This disclosure provides a battery device, including a battery cell from any of the above embodiments.

[0043] This disclosure provides an electrical device, including a battery cell or a battery device of any of the above embodiments, wherein the battery cell or the battery device is used to store or provide electrical energy. Attached Figure Description

[0044] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiments below. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0045] Figure 1 This is a schematic diagram of the vehicle structure according to an embodiment of the present disclosure;

[0046] Figure 2This is an exploded view of a battery device according to an embodiment of this disclosure;

[0047] Figure 3 This is an exploded view of a single battery cell according to an embodiment of this disclosure;

[0048] Figure 4 This is an assembly diagram of the preset shell wall, pressure relief mechanism, adapter piece and insulating component according to an embodiment of the present disclosure. The diagram shows a projected view from the direction of the electrode assembly toward the preset shell wall.

[0049] Figure 5 for Figure 4 A cross-sectional view at position AA in the middle, showing the preset lengths corresponding to the first, second and third exhaust holes respectively;

[0050] Figure 6 for Figure 4 A cross-sectional view at position AA in the middle. The figure shows the axial direction of the first vent, the axial direction of the second vent, the axial direction of the third vent, and the distance between the two sub-walls. The adapter plate is not shown in the figure.

[0051] Figure 7 This is a schematic diagram of the structure of an electrode assembly according to an embodiment of the present disclosure. The electrode assembly shown is a wound electrode assembly.

[0052] Figure 8 This is a schematic diagram of the structure of an electrode assembly according to an embodiment of the present disclosure. The electrode assembly shown is a stacked electrode assembly.

[0053] Explanation of reference numerals in the attached figures

[0054] 1000, Vehicle; 100, Battery Unit; 200, Controller; 300, Motor; 400, Housing; 401, First Housing; 402, Second Housing; 500, Battery Cell; 1, Outer Shell; 11, Pre-set Shell Wall; 12, Housing; 13, End Cap; 2, Electrode Terminal; 3, Electrode Assembly; 31, Positive Electrode; 32, Negative Electrode; 33, Separator; 34, Straight Section; 35, Corner Section; 4, Pressure Relief Mechanism; 5, Insulation Components; 51. Main body; 52. Boss; 521. Exhaust chamber; 522. First wall; 523. Second wall; 5231. Sub-wall; 53. First exhaust hole; 54. Second exhaust hole; 55. Third exhaust hole; 6. Injection hole; 7. Support wall; 8. Adapter piece; R1. First direction; R2. Second direction; R3. Third direction; R4. Axial direction of the second exhaust hole; R5. Axial direction of the third exhaust hole; R6. Axial direction of the first exhaust hole. Detailed Implementation

[0055] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0056] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having” and any variations thereof in the embodiments of this disclosure are intended to cover non-exclusive inclusion.

[0057] In the description of the embodiments of this application, technical terms such as "first," "second," and "third" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0058] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0059] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects are in an "or" relationship.

[0060] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" 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 the embodiments of this application according to the specific circumstances.

[0061] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the technical term "contact" should be interpreted broadly, and can be direct contact, contact through an intermediate medium layer, contact between two contacting parties with substantially no interaction force, or contact between two contacting parties with interaction force.

[0062] In related technologies, during thermal runaway of a battery cell, the ejected material generated by the runaway passes through the insulating component and is discharged to the outside of the battery cell via a pressure relief mechanism, thereby depressurizing the space inside the battery cell's casing. The protrusions on the insulating component can abut against the electrode assembly, inhibiting to some extent the movement of the electrode assembly along the first direction under the influence of the thermal runaway ejected material, and providing some space for the thermal runaway ejected material to flow between the main body of the insulating component and the electrode assembly. The projection area of ​​the pressure relief mechanism along the first direction partially overlaps with the projection area of ​​the main body along the first direction. However, no corresponding vent is provided in the overlapping area of ​​the projection area of ​​the main body along the first direction and the projection area of ​​the pressure relief mechanism along the first direction. This overlapping area is not fully utilized for venting, thus limiting the venting capacity of the battery cell.

[0063] It should be noted that the exhaust capacity is the maximum amount of exhaust gas that a single battery cell is allowed to emit per unit time.

[0064] The exhaust volume here refers to the total amount of material discharged from the exhaust port. In the event of thermal runaway in a single battery cell, the exhaust volume includes the total amount of thermal runaway ejected materials, such as gas, discharged from the exhaust port.

[0065] In this embodiment of the present disclosure, by providing a first vent hole on the main body and making the projection area of ​​the first vent hole located within the projection area of ​​the pressure relief mechanism along the first direction, the projection area of ​​the main body coinciding with the pressure relief mechanism along the first direction is fully utilized for venting. In the event of thermal runaway, the battery cell is allowed to discharge more thermal runaway ejecta per unit time, thereby improving the venting capacity of the battery cell.

[0066] The first vent hole provided on the main body in the embodiments of this application can be used not only for battery cells, but also for battery devices and electrical devices.

[0067] This application provides an electrical device; please refer to [link / reference]. Figure 1 This includes individual battery cells or battery devices used to store or provide electrical energy.

[0068] In some embodiments, the power supply device also includes a device body, and a battery device is mounted on the device body to supply power to the device body.

[0069] Electrical devices are devices that use electrical energy as their energy source to perform corresponding functions by consuming electrical energy. For example, electrical devices can be, but are not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0070] The main body of a device refers to the main structure that consumes electrical energy to perform its corresponding functions. For example, an electrical device can be a mobile phone, where the main body is the part that enables communication and other functions, powered by individual battery cells or battery packs. Similarly, an electrical device can be a car, where the main body is the part that provides seating and allows the vehicle to move on the road, powered by individual battery cells or battery packs.

[0071] The following description will use a vehicle 1000 as an example to illustrate some embodiments of the present application.

[0072] Some embodiments of this application provide a vehicle 1000 that can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. Please refer to... Figure 1 The vehicle 1000 has a battery device 100 installed inside, which can be located at the bottom, front, or rear of the vehicle 1000. The battery device 100 can be used to power the vehicle 1000; for example, it can serve as the vehicle 1000's operating power source. The vehicle 1000 may also include a controller 200 and a motor 300, whereby the controller 200 can control the battery device 100 to supply power to the motor 300. For example, the battery device 100 can meet the power needs of the vehicle 1000 during startup, navigation, and operation.

[0073] In some embodiments of this application, the battery device 100 can not only serve as the operating power source for the vehicle 1000, but also as the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0074] In some embodiments, the battery device 100 may be a battery pack.

[0075] In some embodiments, the battery device 100 may be an energy storage device.

[0076] The battery device 100 of this application embodiment includes a battery cell 500. The battery cell 500 is used to store or provide electrical energy.

[0077] At least two battery cells 500 in the battery device are connected in series, parallel or mixed.

[0078] In this embodiment of the application, the battery cell 500 can be a secondary battery. A secondary battery refers to a battery cell 500 that can be used again after being discharged by recharging to activate the active materials.

[0079] The battery cell 500 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.

[0080] The battery cell 500 includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator, with the separator positioned between the negative and positive electrodes. During the charging and discharging process of the battery cell 500, active ions (such as lithium ions) repeatedly insert and extract between the positive and negative electrodes. The separator, positioned between the positive and negative electrodes, prevents short circuits between the electrodes while allowing active ions to pass through.

[0081] In some embodiments, the positive electrode may be a positive electrode sheet, which may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0082] As an example, the positive current collector has two surfaces opposite each other in its own thickness direction, and the positive active material is disposed on either or both of the two opposite surfaces of the positive current collector.

[0083] As an example, the positive current collector can be a metal foil, a conductive polymer material, a carbon material, or a composite current collector. For example, as a metal foil, pure metals, alloys, or surface-treated metals can be used, including but not limited to stainless steel, copper, aluminum, nickel, titanium, or silver. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (aluminum, aluminum alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0084] As an example, the positive electrode active material may include at least one of the following materials: lithium phosphate, lithium transition metal oxide, and their respective modified compounds. However, this application is not limited to these materials, and other conventional materials that can be used as battery positive electrode active materials may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium phosphate may include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), lithium iron phosphate and carbon composites, lithium manganese phosphate (such as LiMnPO4), lithium manganese phosphate and carbon composites, lithium iron manganese phosphate, and lithium iron manganese phosphate and carbon composites. Examples of lithium transition metal oxide may include, but are not limited to, lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, and lithium nickel cobalt manganese oxide (such as LiNi). 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also known as NCM) 333 LiNi 0.5 Co 0.2 Mn 0.3 O2 (also known as NCM) 523 LiNi 0.5 Co 0.25 Mn 0.25 O2 (also known as NCM) 211 LiNi 0.6 Co 0.2 Mn 0.2 O2 (also known as NCM) 622 LiNi 0.8 Co 0.1 Mn 0.1 O2 (also known as NCM) 811 ), lithium nickel cobalt aluminum oxide (such as LiNi) 0.8 Co 0.15 Al 0.05 At least one of O2 and its modified compounds. Modified compounds refer to substances obtained by modification methods such as doping or coating based on the above-mentioned substances.

[0085] In some embodiments, please refer to Figure 2 The battery device 100 also includes a housing 400, and individual battery cells 500 are installed inside the housing 400.

[0086] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0087] As an example, the negative electrode current collector can be a metal foil, a conductive polymer material, a carbon material, or a composite current collector. For example, as a metal foil, pure metals, alloys, or surface-treated metals can be used, including but not limited to stainless steel, copper, aluminum, nickel, titanium, or silver. The composite current collector may include a polymer material substrate and a metal layer. The composite current collector can be formed by forming a metal material (copper, copper alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0088] As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector.

[0089] As an example, the negative electrode current collector has two surfaces opposite each other in its own thickness direction, and the negative electrode active material is disposed on either or both of the two opposite surfaces of the negative electrode current collector.

[0090] As an example, the negative electrode active material may be a negative electrode active material known in the art for use in battery cell 500. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc. Silicon-based materials may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. Tin-based materials may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, this application is not limited to these materials, and other conventional materials that can be used as negative electrode active materials for battery cell 500 may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0091] In some embodiments, the negative electrode can be made of foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, or a foamed alloy, etc. When foamed metal is used as the negative electrode, the surface of the foamed metal may or may not contain a negative electrode active material.

[0092] In some embodiments, the negative electrode may be made of foamed carbon.

[0093] As an example, negative electrode active materials can be filled or / and deposited within the negative electrode current collector.

[0094] In some embodiments, the positive current collector can be made of aluminum, and the negative current collector can be made of copper.

[0095] In some embodiments, the electrode assembly further includes an isolator disposed between the positive and negative electrodes.

[0096] In some embodiments, the separator is a separator membrane. This application does not impose any particular limitation on the type of separator membrane; any known porous separator membrane with good chemical and mechanical stability can be selected.

[0097] As an example, the main material of the separator can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramic. The separator can be a single-layer film or a multi-layer composite film, without particular limitation. When the separator is a multi-layer composite film, the materials of each layer can be the same or different, without particular limitation. The separator can be a single component located between the positive and negative electrodes, or it can be attached to the surfaces of the positive and negative electrodes. An inorganic particle coating, an organic particle coating, or an organic / inorganic composite coating can also be applied to the surface of the separator.

[0098] In some embodiments, the separator is a solid electrolyte. The solid electrolyte is disposed between the positive and negative electrodes, serving both to transport ions and to isolate the positive and negative electrodes.

[0099] In some embodiments, the battery cell 500 also includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. This application does not impose specific limitations on the type of electrolyte; it can be selected according to requirements. The electrolyte can be liquid, gel, or solid.

[0100] Liquid electrolytes include electrolyte salts and solvents.

[0101] In some embodiments, the electrolyte salt may be selected from at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalate borate, lithium dioxalate borate, lithium difluorodioxalate phosphate, and lithium tetrafluorooxalate phosphate.

[0102] In some embodiments, the solvent may be selected from at least one of ethylene carbonate, propylene carbonate, methyl ethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butyl carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone, and diethyl sulfone. The solvent may also be an ether solvent. Ether solvents may include one or more of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyl tetrahydrofuran, diphenyl ether, and crown ethers.

[0103] In some embodiments, the electrolyte may optionally include additives. For example, additives may include negative electrode film-forming additives, positive electrode film-forming additives, and additives that can improve certain performance of the battery cell 500, such as additives that improve the overcharge / fast charge performance of the battery cell 500, additives that improve the high-temperature performance of the battery cell 500, additives that improve the low-temperature performance of the battery cell 500, etc.

[0104] The gel electrolyte includes a polymer as a backbone network and can be used in conjunction with an ionic liquid-lithium salt.

[0105] Solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0106] As an example, the polymers of polymeric solid electrolytes may include polyethers (polyoxyethylene), polysiloxanes, polycarbonates, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, monoionic polymers, polyionic liquids, cellulose, etc.

[0107] As an example, inorganic solid electrolytes can be one or more of the following: oxide solid electrolytes (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON thin film), sulfide solid electrolytes (crystalline lithium superconducting ion conductor (lithium germanium phosphorus sulfide, silver sulfide germanium ore), amorphous sulfides), halide solid electrolytes, nitride solid electrolytes, and hydride solid electrolytes.

[0108] As an example, composite solid electrolytes are formed by adding inorganic solid electrolyte fillers to polymer solid electrolytes.

[0109] The electrode assembly can be a wound structure, a stacked structure, or a hybrid structure of wound and stacked.

[0110] In some implementations, the electrode assembly is a wound structure. The positive and negative electrode sheets are wound into a wound structure.

[0111] In some implementations, the electrode assembly is a stacked structure.

[0112] As an example, multiple positive and negative electrodes can be set, and multiple positive and multiple negative electrodes can be stacked alternately.

[0113] As an example, multiple positive electrode plates can be provided, and negative electrode plates can be folded to form multiple stacked folded segments, with a positive electrode plate sandwiched between adjacent folded segments.

[0114] As an example, both the positive and negative electrode plates are folded to form multiple stacked folded segments.

[0115] As an example, multiple separators can be provided, each positioned between any adjacent positive or negative electrode plates.

[0116] As an example, the separators can be continuously arranged, either by folding or rolling between any adjacent positive or negative electrode plates.

[0117] In some embodiments, the electrode assembly can be cylindrical, flat, or polygonal, etc.

[0118] In some embodiments, the electrode assembly is provided with tabs that allow current to be drawn from the electrode assembly. The tabs include a positive tab and a negative tab.

[0119] In some embodiments, please refer to Figure 2 The battery device 100 also includes a housing 400, and individual battery cells 500 are installed inside the housing 400.

[0120] As an example, the housing 400 may include a first housing 401 and a second housing 402. The first housing 401 and the second housing 402 are fastened together to form a closed space inside the housing 400 to house the battery cell assembly. Here, "closed" refers to covering or closing, and can be either sealed or unsealed. The first housing 401 may be a top cover or a bottom plate.

[0121] For the battery cell 500 in this embodiment, please refer to [link / reference needed]. Figure 3 and Figure 4 The battery cell 500 includes a housing 1, electrode terminals 2, electrode assemblies 3, a pressure relief mechanism 4, and an insulating member 5. One of the housing walls of the housing 1 is a preset housing wall 11. The electrode terminals 2 are disposed in the housing 1. The electrode assemblies 3 are located inside the housing 1 and electrically connected to the electrode terminals 2. The preset housing wall 11 and the electrode assemblies 3 are arranged in a first direction R1. The pressure relief mechanism 4 is disposed in the preset housing wall 11. The insulating member 5 is located between the preset housing wall 11 and the electrode assemblies 3. The insulating member 5 has multiple vent holes penetrating the insulating member 5. The insulating member 5 includes a body 51 and a boss 52 connected to each other. The boss 52 is located between the body 51 and the electrode assemblies 3 along the first direction R1. The vent hole formed in the body 51 is a first vent hole 53. Along the first direction R1, the projection area of ​​the first vent hole 53 is located within the projection area of ​​the pressure relief mechanism 4.

[0122] The electrode assembly 3 is located inside the housing 1, which is used to house and protect the electrode assembly 3.

[0123] For example, electrode terminal 2 can be a pole post.

[0124] Electrode assembly 3 is the main structure for converting electrical energy and chemical energy into each other. Electrode assembly 3 is charged through electrode terminal 2, or electrode assembly 3 is discharged to the outside through electrode terminal 2.

[0125] For example, please refer to Figure 3 Electrode terminals 2 are installed on the preset shell wall 11.

[0126] The pressure relief mechanism 4 is mainly used to relieve pressure in the space inside the outer casing 1 when the pressure inside the outer casing 1 is high. For example, when the battery cell 500 experiences thermal runaway, the ejected gases and other substances generated by the thermal runaway increase the pressure inside the space inside the outer casing 1. When the pressure inside the outer casing 1 reaches a certain level, the pressure relief mechanism 4 opens to discharge the ejected gases and other substances generated by the thermal runaway inside the outer casing 1, thereby relieving pressure in the space inside the outer casing 1 of the battery cell 500.

[0127] For example, the pressure relief mechanism 4 can be an explosion-proof valve.

[0128] The insulating element 5 is located between the preset housing 12 and the electrode assembly 3. The insulating element 5 is mainly used to insulate the space between the preset housing wall 11 and the electrode assembly 3.

[0129] For example, the insulating element 5 can be a plastic material.

[0130] For example, each vent hole extends through the insulation 5.

[0131] For example, the first vent 53 is circular in shape.

[0132] For example, the projection area of ​​the boss 52 is at least partially located within the projection area of ​​the pressure relief mechanism 4.

[0133] In this embodiment, the boss 52 of the insulating member 5 is connected to the main body 51. The boss 52 is located between the main body 51 and the electrode assembly 3 along the first direction R1. The boss 52 can abut against the electrode assembly 3 to suppress the electrode assembly 3 from moving towards the main body 51 under the action of thermal runaway ejection, so that the main body 51 and the electrode assembly 3 can maintain a good distance, providing a certain space for the thermal runaway ejection to flow between the main body 51 and the electrode assembly 3, reducing the possibility that the first exhaust hole 53 on the main body 51 will be blocked by the electrode assembly 3, so that the ejection such as gas generated by the electrode assembly 3 during thermal runaway can pass through the first exhaust hole 53 better. Since the projection area of ​​the first exhaust hole 53 along the first direction R1 is located in the projection area of ​​the pressure relief mechanism 4 along the first direction R1, the ejection such as gas generated by thermal runaway discharged from the first exhaust hole 53 can be discharged from the pressure relief mechanism 4 more smoothly, and pressure relief is better achieved. The main body 51 is provided with a first exhaust port 53, and the projection area of ​​the first exhaust port 53 along the first direction R1 is located in the projection area of ​​the pressure relief mechanism 4 along the first direction R1. The exhaust port 53 discharges gases and other thermal runaway ejected materials. It can make full use of the area where the projection area of ​​the main body 51 along the first direction R1 and the projection area of ​​the pressure relief mechanism 4 along the first direction R1 overlap to discharge gases and other thermal runaway ejected materials, thereby improving the exhaust capacity of the battery cell 500. During the process of thermal runaway of the battery cell 500, gases and other thermal runaway ejected materials can be discharged better.

[0134] In some embodiments, please refer to Figure 3 and Figure 4 The battery cell 500 has an injection hole 6 that penetrates the preset shell wall 11 and the insulating member 5. The injection hole 6 and the pressure relief mechanism 4 are arranged in the second direction R2. The second direction R2 is intersected with the first direction R1. Part of the first vent hole 53 is located on the side of the boss 52 facing the injection hole 6 along the second direction R2.

[0135] The injection port 6 is used to inject electrolyte into the space inside the housing 1 that houses the electrode assembly 3.

[0136] For example, the second direction R2 can be perpendicular to the first direction R1.

[0137] Part of the first vent hole 53 is located on the side of the boss 52 facing the injection hole 6 along the second direction R2. Since the projection area of ​​the first vent hole 53 along the first direction R1 is located within the projection area of ​​the pressure relief mechanism 4 along the first direction R1, part of the projection area of ​​the pressure relief mechanism 4 is located on the side of the boss 52 facing the injection hole 6 along the second direction R2. The boss 52 does not completely cover the pressure relief mechanism 4 at least along the second direction R2.

[0138] For example, please refer to Figure 3The outer casing 1 includes a housing 12 and an end cap 13 covering the housing 12. The housing 12 is connected to the end cap 13, and the electrode assembly 3 is located in the space enclosed by the housing 12 and the end cap 13.

[0139] For example, the shell wall corresponding to the end cap 13 is a preset shell wall 11. The electrode terminal 2 is mounted on the end cap 13, and / or, the pressure relief mechanism 4 is mounted on the end cap 13.

[0140] For example, the housing 12 and the end cap 13 are welded together.

[0141] For example, the second direction R2 is arranged along the length direction of the end cap 13.

[0142] A portion of the first vent hole 53 is located on the side of the boss 52 facing the injection hole 6 along the second direction R2, and this portion of the first vent hole 53 is located between the boss 52 and the injection hole 6 along the second direction.

[0143] In this embodiment, a portion of the first vent hole 53 is located on the side of the boss 52 facing the injection hole 6 along the second direction R2. The boss 52 does not completely cover the side of the pressure relief mechanism 4 facing the injection hole 6 along the second direction, and there is a relatively large distance between the boss 52 and the injection hole 6. Even if the electrolyte is injected into the housing 1 in a diffuse manner from the injection hole 6, the large distance between the boss 52 and the injection hole 6 reduces the possibility of the electrolyte diffusing and adhering to the boss 52, allowing the electrolyte injected into the housing 1 from the injection hole 6 to flow as far as possible towards the electrode assembly 3 to wet the electrode assembly 3.

[0144] For example, the position of the first injection hole 6 is not limited. For example, the projection area of ​​the main body 51 of the boss 52 facing the injection hole 6 along the second direction R2 in the first direction R1 does not coincide with the projection area of ​​the pressure relief mechanism 4 along the first direction R1. The first vent hole 53 is not provided between the boss 52 and the injection hole 6 along the second direction R2. The first vent hole 53 is located on the side of the boss 52 away from the injection hole 6 along the second direction R2.

[0145] In some embodiments, please refer to Figure 7 and Figure 8 The boss 52 is spanned across the pressure relief mechanism 4 on both sides along the third direction R3, and the third direction R3 is arranged to intersect with the first direction R1 and the second direction R2 respectively.

[0146] The boss 52 is positioned across the opposite sides of the pressure relief mechanism 4 along a third direction R3, meaning that the boss 52 extends from one side of the pressure relief mechanism 4 to the other side along the third direction R3. Specifically, when projected along the first direction, the area in the projected region of the boss 52 that does not overlap with the projected region of the pressure relief mechanism 4 is called the first region. Part of the first region is located on one side of the projected region of the pressure relief mechanism 4 along the third direction R3, and part of the first region is located on the other side of the projected region of the pressure relief mechanism 4 along the third direction R3.

[0147] For example, the projection area of ​​the boss 52 is at least partially located within the projection area of ​​the pressure relief mechanism 4, and the area where the projection area of ​​the boss 52 overlaps with the projection area of ​​the pressure relief mechanism 4 is the second area, which is located between the two first areas along the third direction R3.

[0148] For example, the electrode assembly 3 has a flat region 34. The electrode assembly 3 includes a positive electrode 31, a negative electrode 32 and a separator 33. The separator 33 is disposed between the positive electrode 31 and the negative electrode 32. The positive electrode 31 and the negative electrode 32 are stacked in the flat region 34 in the third direction R3.

[0149] The positive electrode 31 and the negative electrode 32 are stacked in the straight region 34 in the direction of the third direction R3, and the large surface of the electrode assembly 3 is basically perpendicular to the third direction R3.

[0150] The "large surface" here refers to the outer surface with the largest area among the outer surfaces of electrode assembly 3.

[0151] For example, the third direction R3 is perpendicular to the first direction R1 and the second direction R2, respectively.

[0152] For example, the third party R3 is arranged along the width direction of the end cap 13.

[0153] For example, the positive electrode 31, the negative electrode 32 and the separator 33 are wound together into a wound structure, and the electrode assembly 3 is a wound electrode assembly 3. The electrode assembly 3 also has a corner region 35. The corner regions 35 are provided on opposite sides of the straight region 34. The arrangement direction of the corner regions 35 on both sides is arranged to cross the axial direction of the third direction R3 and the winding shaft, respectively.

[0154] For example, the two corner areas 35 are arranged along the second direction R2.

[0155] For example, the positive electrode 31 and the negative electrode 32 are stacked in sequence to form a stacked structure, and the electrode assembly 3 is a stacked electrode assembly 3.

[0156] In this embodiment, the injection hole 6 restricts the arrangement space of the boss 52 in the second direction R2, while the arrangement of the boss 52 in the third direction R3 is not greatly restricted. The boss 52 is arranged across the opposite sides of the pressure relief mechanism 4 along the third direction R3, so that the boss 52 has a large contact surface when it abuts against the electrode assembly 3, which is beneficial to suppress the movement of the electrode assembly 3 along the first direction R1.

[0157] It is understood that the arrangement of the boss 52 is not limited. For example, the projection area of ​​the boss 52 along the first direction R1 is located within the projection area of ​​the pressure relief mechanism 4 along the first direction R1.

[0158] In some embodiments, please refer to Figure 4 Part of the first vent hole 53 is located on the side of the boss 52 away from the injection hole 6 along the second direction R2.

[0159] Part of the first vent hole 53 is located on the side of the boss 52 away from the injection hole 6 along the second direction R2, and part of the first vent hole 53 is located on the side of the boss 52 towards the injection hole 6 along the second direction R2.

[0160] In this embodiment, the area where the projection area of ​​the main body 51 on both sides of the boss 52 along the first direction R1 overlaps with the projection area of ​​the pressure relief mechanism 4 along the first direction R1 can be fully utilized for venting, thereby improving the venting capacity of the battery cell 500.

[0161] It is understood that the arrangement of the first vent 53 is not limited. For example, the first vent 53 is located on one side of the boss 52 along the second direction R2, and the other side of the boss 52 along the second direction R2 does not have a first vent 53.

[0162] In some embodiments, please refer to Figures 4-6 The boss 52 has an exhaust chamber 521. The projection area of ​​the exhaust chamber 521 along the first direction R1 at least partially overlaps with the projection area of ​​the pressure relief mechanism 4 along the first direction R1. The chamber walls on opposite sides of the exhaust chamber 521 along the second direction R2 are first walls 522. The exhaust hole formed on the first wall 522 is a second exhaust hole 54 communicating with the exhaust chamber 521. The first wall 522 of the exhaust chamber 521 facing the injection hole 6 has a second exhaust hole 54.

[0163] The boss 52 has an exhaust chamber 521. The projection area of ​​the exhaust chamber 521 along the first direction R1 at least partially overlaps with the projection area of ​​the pressure relief mechanism 4 along the first direction R1. Gas and other thermally runaway ejected materials enter the exhaust chamber 521 through the exhaust hole connected to the exhaust chamber 521, collect, and are discharged from the pressure relief mechanism 4.

[0164] For example, the second exhaust port 54 is elliptical in shape.

[0165] In this embodiment, the first wall 522 of the vent chamber 521 facing the injection hole 6 has a second vent hole 54. Even when the boss 52 abuts against the electrode assembly 3 along the first direction R1, thermally runaway ejected materials such as gas can still enter the vent chamber 521 through the second vent hole 54 on the first wall 522 and be discharged from the pressure relief mechanism 4, which facilitates better venting and improves the venting capacity of the battery cell 500. The vent chamber 521 guides the thermally runaway ejected materials to converge in the vent chamber 521 and then concentrate them out from the pressure relief mechanism 4, reducing the disorderly diffusion of the thermally runaway ejected materials. Since the boss 52 has a first vent hole 53 along the second direction R2 facing the injection hole 6, and the distance between the injection hole 6 and the second vent hole 54 is relatively large, the possibility of electrolyte remaining in the vent chamber 521 due to the electrolyte being diffusely injected into the casing 1 from the injection hole 6 entering the vent chamber 521 through the second vent hole 54 can be reduced.

[0166] It is understood that the arrangement of the vent is not limited. For example, the second vent 54 is located on the first wall 522 of the vent chamber 521 on the side opposite to the injection hole 6, and the second vent 54 may not be provided on the first wall 522 of the vent chamber 521 on the side facing the injection hole 6; or, the vent may not be provided on the boss 52.

[0167] In some embodiments, please refer to Figures 4-6 The number of second exhaust holes 54 is at least one, and the projected area of ​​each second exhaust hole 54 along the axial direction R4 of the corresponding second exhaust hole is 14 mm. 2 ~22mm 2 .

[0168] For example, the axial direction R4 of the second vent is arranged along the thickness direction of the first wall 522.

[0169] For example, the projected area of ​​each second exhaust hole 54 along the axial direction R4 of the corresponding second exhaust hole is 14 mm. 2 16mm 2 18mm 2 20mm 2 21mm 2 Or 22mm 2 .

[0170] In this embodiment of the present disclosure, the projected area of ​​each second exhaust hole 54 along the axial direction R4 of the corresponding second exhaust hole is 14mm². 2 ~22mm 2 This makes the area of ​​the second exhaust hole 54 more suitable, which can both exhaust air well and make the first wall 522 have better structural strength.

[0171] It is understood that the projected area of ​​each second exhaust hole 54 along the axial direction R4 of the corresponding second exhaust hole can be determined according to actual needs. For example, the projected area of ​​each second exhaust hole 54 along the axial direction R4 of the corresponding second exhaust hole can be appropriately less than 14 mm. 2 Alternatively, the projected area of ​​each second exhaust port 54 along the axial direction R4 of the corresponding second exhaust port can be appropriately greater than 22mm. 2 .

[0172] In some embodiments, please refer to Figure 4 The number of second exhaust holes 54 on at least one side of the first wall 522 is multiple. The directions in which the multiple second exhaust holes 54 are arranged intersecting the first direction R1 and the second direction R2 respectively. Along the direction in which the multiple second exhaust holes 54 are arranged, the distance between two adjacent second exhaust holes 54 is 2.5mm to 4mm.

[0173] For example, please refer to Figure 4 Multiple second exhaust ports 54 are arranged sequentially along the third direction R3.

[0174] For example, the distance between two adjacent second exhaust holes 54 is 2.5mm, 2.7mm, 2.9mm, 3.1mm, 3.2mm, 3.5mm, 3.7mm, 3.9mm or 4mm.

[0175] For example, the distance between two adjacent second exhaust holes 54 is D1, where 2.5mm≤D1≤4mm.

[0176] In this embodiment, the distance between two adjacent second exhaust holes 54 is 2.5mm to 4mm, which makes the distance between two adjacent second exhaust holes 54 more suitable. While providing as many second exhaust holes 54 as possible, the first wall 522 still has good mechanical strength.

[0177] It is understood that the distance between two adjacent second exhaust holes 54 is not limited. For example, the distance between two adjacent second exhaust holes 54 may be slightly less than 2.5 mm; or, the distance between two adjacent second exhaust holes 54 may be slightly greater than 4 mm.

[0178] In some embodiments, please refer to Figures 4-6 The cavity wall of the exhaust chamber 521 facing the electrode assembly 3 along the first direction R1 is the second wall 523, and the exhaust hole formed on the second wall 523 is the third exhaust hole 55 communicating with the exhaust chamber 521.

[0179] The third exhaust port 55 is connected to the exhaust chamber 521. Gas and other thermally runaway ejected materials enter the exhaust chamber 521 from the third exhaust port 55 and are discharged from the pressure relief mechanism 4 after accumulating in the exhaust chamber 521.

[0180] The side wall of the exhaust chamber 521 facing the electrode assembly 3 along the first direction R1 is a second wall 523. The second wall 523 is used to abut against the electrode assembly 3 to suppress the electrode assembly 3 from moving along the first direction R1 under the action of thermal runaway ejected material.

[0181] For example, the third exhaust port 55 is shaped like a racetrack.

[0182] In this embodiment, since the third vent 55 is formed on the second wall 523, even when the second wall 523 abuts against the electrode assembly 3 along the first direction R1, the gas in the part of the electrode assembly 3 covered by the second wall 523 can still be collected in the vent chamber 521 through the third vent 55 and discharged from the pressure relief mechanism 4, which is beneficial for the battery cell 500 to vent better during thermal runaway. Furthermore, even if some electrolyte enters the vent chamber 521 from the second vent 54 on the first wall 522 from the electrolyte injected into the casing 1 in a diffuse manner from the injection hole 6, this part of the electrolyte entering the vent chamber 521 can also flow to the electrode assembly 3 through the third vent 55 on the second wall 523 as much as possible, which is beneficial for reducing the electrolyte residue in the vent chamber 521 and allowing the electrolyte to better wet the electrode assembly 3.

[0183] It is understood that the arrangement of the vent is not limited. For example, the third vent 55 may be omitted from the second wall 523 as appropriate.

[0184] In some embodiments, please refer to Figures 4-6 The maximum length of the projection area formed by the axial projection of each exhaust hole along the corresponding exhaust hole is a preset length. The preset length of the third exhaust hole 55 is greater than the preset length of the second exhaust hole 54, and the preset length of the second exhaust hole 54 is greater than the preset length of the first exhaust hole 53.

[0185] For example, please refer to Figures 4-6 The third exhaust port 55 is shaped like a racetrack, and its length is arranged along the second direction R2. The preset length of the third exhaust port 55 is the maximum span of the third exhaust port 55 along the second direction R2.

[0186] For example, please refer to Figures 4-6 The second exhaust port 54 is elliptical in shape, and its length is arranged along the major axis of the ellipse. The preset length of the second exhaust port 54 is the maximum span of the second exhaust port 54 along the major axis of the ellipse.

[0187] For example, please refer to Figures 4-6 The first exhaust hole 53 is circular in shape, and the preset length of the first exhaust hole 53 is the diameter of the first exhaust hole 53.

[0188] For example, please refer to Figures 4-6 The preset length of the first exhaust hole 53 is L1, the preset length of the second exhaust hole 54 is L2, and the preset length of the third exhaust hole 55 is L3, where L3>L2>L1.

[0189] In this embodiment, the third vent 55 is located on the second wall 523, which abuts against the electrode assembly 3 to resist its movement along the first direction R1. The third vent 55 has a relatively long preset length, and the second wall 523 has a large dimension in the corresponding direction, which facilitates better contact between the second wall 523 and the electrode assembly 3 to suppress its movement along the first direction R1. Due to the limited space for the boss 52, the arrangement space of the first wall 522 is limited when the second wall 523 is large. The preset length of the second vent 54 is smaller than the preset length of the third vent 55, which facilitates better arrangement of the second vent 54 on the first wall 522. With the second vent 54 and the third vent 55 arranged on the boss 52, most of the thermal runaway ejected material is discharged through the exhaust chamber 521 via the second vent 54 and the third vent 55. The preset length of the second vent 54 is greater than the preset length of the first vent 53. Setting the preset length of the second vent 54 to be longer is beneficial for the thermal runaway ejected material to be discharged better from the second vent 54. The preset length of the first vent 53 is set to be shorter, which can leave a certain space for the first vent 53 and the second vent 54 to be arranged better.

[0190] It is understood that the preset lengths of the first vent 53, the second vent 54, and the third vent 55 are not limited. For example, the preset lengths of the first vent 53, the second vent 54, and the third vent 55 may be equal.

[0191] In some embodiments, please refer to Figure 4 The number of third exhaust holes 55 is at least one, and the projected area of ​​each third exhaust hole 55 along the axial direction R5 of the corresponding third exhaust hole is 40mm. 2 ~50mm 2 .

[0192] For example, the projected area of ​​each third exhaust port 55 along the axial direction R5 of the corresponding third exhaust port is 40 mm. 2 42mm 2 44mm 2 45mm 2 46mm 2 48mm 2 50mm 2 .

[0193] In this embodiment, the area of ​​the third vent 55 is suitable, which can not only effectively discharge the thermally runaway ejected material, but also give the second wall 523 good mechanical strength.

[0194] In some embodiments, please refer to Figure 4 There are multiple third exhaust holes 55, and the arrangement directions of the multiple third exhaust holes 55 are respectively intersecting the first direction R1 and the second direction R2. Along the arrangement direction of the multiple third exhaust holes 55, the distance between two adjacent third exhaust holes 55 is 2.5mm to 4mm.

[0195] For example, please refer to Figure 4 The multiple third exhaust ports 55 are arranged along the third direction R3.

[0196] For example, the distance between two adjacent third exhaust holes 55 is 2.5mm, 2.7mm, 2.9mm, 3.1mm, 3.2mm, 3.5mm, 3.7mm, 3.9mm or 4mm.

[0197] For example, the distance between two adjacent third exhaust holes 55 is D2, where 2.5mm≤D2≤4mm.

[0198] In this embodiment, the distance between two adjacent third exhaust holes 55 is 2.5mm to 4mm, which makes the distance between two adjacent third exhaust holes 55 more suitable. While providing as many third exhaust holes 55 as possible, the second wall 523 still has good mechanical strength.

[0199] It is understood that the distance between two adjacent third exhaust holes 55 is not limited. For example, the distance between two adjacent third exhaust holes 55 may be slightly less than 2.5 mm; or, the distance between two adjacent third exhaust holes 55 may be slightly greater than 4 mm.

[0200] In some embodiments, please refer to Figures 4-6 The second wall 523 is located between the two first walls 522 along the second direction R2. The second wall 523 is located on the side of the main body 51 facing the electrode assembly 3 along the first direction R1. Each first wall 522 is connected to the second wall 523 and the corresponding main body 51 respectively. The projection area of ​​the second wall 523 is arranged alternately with the projection area of ​​the main body 51 along the first direction R1.

[0201] For example, the cross-sectional shape of the boss 52 is generally trapezoidal.

[0202] The second wall 523 is located between the two first walls 522 along the second direction R2. The second wall 523 is located on the side of the main body 51 facing the electrode assembly 3 along the first direction R1. Each first wall 522 is connected to the second wall 523 and the corresponding main body 51 respectively. The projection area of ​​the second wall 523 and the projection area of ​​the main body 51 are arranged alternately along the first direction R1, so that the two first walls 522 are arranged at an angle.

[0203] In this embodiment, the inclined arrangement of the first walls 522 on both sides is beneficial to increasing the area of ​​the first walls 522. More second exhaust holes 54 can be arranged on the first walls 522 to facilitate the discharge of thermally runaway ejected material. The inclined first walls 522 can guide the thermally runaway ejected material to the exhaust chamber 521 for better collection and discharge.

[0204] In some embodiments, please refer to Figures 4-6 The second wall 523 includes two sub-walls 5231 arranged at intervals along the second direction R2. At least one sub-wall 5231 is provided with a second vent hole 54. The distance between the two sub-walls 5231 along the second direction R2 is 1mm to 5mm.

[0205] For example, please refer to Figure 5 and Figure 6 The battery cell 500 also includes two support walls 7 located in the exhaust chamber 521. The two support walls 7 are arranged at intervals along the second direction R2. One end of each support wall 7 along the first direction R1 is connected to the corresponding sub-wall 5231, and the other end of each support wall 7 along the second direction R2 is in contact with the preset shell wall 11 and / or the pressure relief mechanism 4.

[0206] For example, please refer to Figure 6 The distance between the two sub-walls 5231 along the second direction R2 is D3, 1mm≤D3≤5mm.

[0207] For example, please refer to Figure 6 The two supporting walls 7 are arranged at intervals of 1mm to 5mm along the second direction R2.

[0208] For example, the distance between the two sub-walls 5231 along the second direction R2 is the same as the distance between the two support walls 7 along the second direction R2.

[0209] For example, the distance between the two sub-walls 5231 along the second direction R2 is 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm or 5mm.

[0210] In this embodiment, the distance between the two sub-walls 5231 is appropriate, and the thermal runaway ejecta can be better collected from between the two sub-walls 5231 into the exhaust chamber 521 and discharged from the pressure relief mechanism 4, which is beneficial for the battery cell 500 to better exhaust.

[0211] It is understood that the distance between the two sub-walls 5231 along the second direction R2 is not limited. For example, the distance between the two sub-walls 5231 along the second direction R2 can be slightly less than 1 mm; or, the distance between the two sub-walls 5231 along the second direction R2 can be slightly greater than 5 mm.

[0212] In some embodiments, please refer to Figure 4 The number of first exhaust holes 53 is at least one, and the projected area of ​​each first exhaust hole 53 along the axial direction R6 of the corresponding first exhaust hole is 10mm. 2 ~14mm 2 .

[0213] For example, the projected area of ​​each first exhaust hole 53 along the axial direction R6 of the corresponding first exhaust hole can be 10 mm. 2 10.5mm 2 11mm 2 11.5mm 2 12mm 2 12.5mm 2 13mm 2 13.5mm 2 Or 14mm 2 .

[0214] In this embodiment of the present disclosure, the projected area of ​​each first exhaust hole 53 along the axial direction R6 of the corresponding first exhaust hole is 10mm². 2 ~14mm 2 This ensures that the area of ​​the first exhaust port 53 is suitable, so that the first exhaust port 53 can effectively discharge the thermally runaway ejected material and give the main body 51 suitable mechanical strength.

[0215] It is understood that the projected area of ​​each first exhaust hole 53 along the axial direction R6 of the corresponding first exhaust hole is not limited. For example, the projected area of ​​each first exhaust hole 53 along the axial direction R6 of the corresponding first exhaust hole can be slightly less than 10 mm². 2 Alternatively, the projected area of ​​each first exhaust port 53 along the axial direction R6 of the corresponding first exhaust port can be slightly larger than 14mm². 2 .

[0216] In some embodiments, please refer to Figure 4 Along the first direction R1, the projected area of ​​the pressure relief mechanism 4 is 780 mm². 2 ~950mm2 .

[0217] For example, please refer to Figure 4 The projected area of ​​the explosion-proof valve along the first direction R1 is 780 mm². 2 ~950mm 2 .

[0218] For example, the explosion-proof valve is in the shape of a sheet.

[0219] For example, the projected area of ​​the pressure relief mechanism 4 along the first direction R1 is 780 mm². 2 790mm 2 800mm 2 830mm 2 850mm 2 870mm 2 890mm 2 910mm 2 930mm 2 Or 950mm 2 .

[0220] In this embodiment, the projected area of ​​the pressure relief mechanism 4 along the first direction R1 is 780 mm². 2 ~950mm 2 This makes the area of ​​the pressure relief mechanism 4 more suitable. The pressure relief mechanism 4 has a large area for pressure relief to facilitate the discharge of thermal runaway ejected material, and the outer shell 1 on which the pressure relief mechanism 4 is installed has more suitable mechanical strength.

[0221] It is understood that the projected area of ​​the pressure relief mechanism 4 is not limited. For example, the projected area of ​​the pressure relief mechanism 4 along the first direction R1 can be slightly less than 780 mm². 2 Alternatively, the projected area of ​​the pressure relief mechanism 4 along the first direction R1 can be slightly larger than 950 mm². 2 .

[0222] In some embodiments, please refer to Figures 4-6 The projected area of ​​each vent hole along its corresponding axial direction is a preset area, and the sum of the preset areas of all vent holes is 1000 mm². 2 ~1200mm 2 .

[0223] For example, the sum of the preset areas of all exhaust holes is equal to the sum of the preset areas of all first exhaust holes 53 plus the sum of the preset areas of all second exhaust holes 54 plus the sum of the preset areas of all third exhaust holes 55.

[0224] For example, the sum of the preset areas of all vents is 1000 mm². 2 1020mm 21040mm 2 1060mm 2 1080mm 2 1100mm 2 1150mm 2 1180mm 2 Or 1200mm 2 .

[0225] In this embodiment, the sum of the preset areas of all vent holes is 1000 mm². 2 ~1200mm 2 This ensures that the area of ​​the vent is suitable, allowing it to effectively discharge thermally runaway ejected material, while also ensuring that the mechanical strength of the insulating component 5 with the vent is appropriate.

[0226] Understandably, the sum of the preset areas of all vents can be slightly less than 1000 mm². 2 Alternatively, the sum of the preset areas of all vents can be slightly greater than 1200 mm². 2 .

[0227] In some embodiments, the projected area of ​​the pressure relief mechanism 4 along the first direction R1 is 780 mm². 2 ~950mm 2 The projected area of ​​each vent hole along its corresponding axial direction is a preset area, and the sum of the preset areas of all vent holes is 1000 mm². 2 ~1200mm 2 .

[0228] In this embodiment, the sum of the preset areas of the exhaust holes and the projected area of ​​the pressure relief mechanism 4 can be well matched, so that the thermally runaway ejected material can be discharged well through the exhaust holes and the pressure relief mechanism 4 in sequence.

[0229] This disclosure provides a battery cell 500. Please refer to [link / reference]. Figures 3-8The battery cell 500 includes a housing 1, electrode terminals 2, electrode assemblies 3, a pressure relief mechanism 4, and an insulating member 5. One of the housing walls of the housing 1 is a pre-set housing wall 11. The electrode terminals 2 are disposed in the housing 1. The electrode assemblies 3 are located inside the housing 1 and electrically connected to the electrode terminals 2. The arrangement direction of the pre-set housing wall 11 and the electrode assemblies 3 is a first direction R1. The pressure relief mechanism 4 is disposed in the pre-set housing wall 11. The insulating member 5 is located between the pre-set housing wall 11 and the electrode assemblies 3. The insulating member 5 has multiple vent holes penetrating the insulating member 5. The insulating member 5 includes a body 51 and a boss 52 connected to each other. The boss 52 is located between the body 51 and the electrode assemblies 3 along the first direction R1. The vent hole formed in the body 51 is a first vent hole 53. Along the first direction R1, the projection area of ​​the boss 52 is at least partially located within the projection area of ​​the pressure relief mechanism 4, and the projection area of ​​the first vent hole 53 is located within the projection area of ​​the pressure relief mechanism 4. Along the first direction R1, the projected area of ​​the explosion-proof valve is 780 mm². 2 ~950mm 2 The projected area of ​​each vent hole along its corresponding axial direction is a preset area, and the sum of the preset areas of all vent holes is 1000 mm². 2 ~1200mm 2The battery cell 500 has an injection hole 6 penetrating the pre-set shell wall 11 and the insulating member 5. The injection hole 6 and the boss 52 are arranged in a second direction R2, which intersects with the first direction R1. The boss 52 has a first vent hole 53 on the side facing the injection hole 6 along the second direction R2. The boss 52 has a vent chamber 521. The projection area of ​​the vent chamber 521 along the first direction R1 at least partially overlaps with the projection area of ​​the pressure relief mechanism 4 along the first direction R1. The cavity walls on opposite sides of the vent chamber 521 along the second direction R2 are first walls 522. The vent holes formed on the first walls 522 are second vent holes 54 communicating with the vent chamber 521. The first wall 522 on the side of the vent chamber 521 facing the injection hole 6 has the second vent hole 54. The cavity wall on the side of the vent chamber 521 facing the electrode assembly 3 along the first direction R1 is a second wall 523. The vent holes formed on the second walls 523 are third vent holes 55 communicating with the vent chamber 521. The second wall 523 includes two sub-walls 5231 spaced apart along the second direction R2, with a distance of 1mm to 5mm between them. The second wall 523 is located between the two first walls 522 along the second direction R2, on the side of the main body 51 facing the electrode assembly 3 along the first direction R1. Each first wall 522 is connected to the second wall 523 and the corresponding main body 51, projected along the first direction R1. The projection area of ​​the second wall 523 is spaced apart from the projection area of ​​the main body 51. The first exhaust port 53 is circular and is uniformly arranged in the area where the projection area of ​​the main body 51 along the first direction R1 overlaps with the projection area of ​​the pressure relief mechanism 4 along the first direction R1. The second exhaust port 54 is elliptical and is uniformly arranged on the first wall 522. The third exhaust port 55 is racetrack-shaped and is uniformly arranged on the second wall 523. The number of third exhaust holes 55 is at least one, and the projected area of ​​each third exhaust hole 55 along the axial direction R5 of the corresponding third exhaust hole is 40mm. 2 ~50mm 2 There are multiple third exhaust holes 55, arranged in a direction that intersects the first direction R1 and the second direction R2, respectively. The distance between any two adjacent third exhaust holes 55 is 2.5 mm to 4 mm along the arrangement direction. There is at least one second exhaust hole 54, and the projected area of ​​each second exhaust hole 54 along the axial direction R4 is 14 mm². 2 ~22mm 2The first wall 522 on at least one side has multiple second vent holes 54. These second vent holes 54 are arranged sequentially in directions intersecting the first direction R1 and the second direction R2, respectively. Along the direction in which the second vent holes 54 are arranged sequentially, the distance between two adjacent second vent holes 54 is 2.5 mm to 4 mm. The first vent hole 53 has at least one first vent hole 53, and the projected area of ​​each first vent hole 53 along the axial direction R6 of the corresponding first vent hole is 10 mm². 2 ~14mm 2 The positive and negative tabs of the electrode assembly 3 are electrically connected to the corresponding adapter piece 8, and the adapter piece 8 is electrically connected to the corresponding electrode terminal 2.

[0230] The above embodiments are merely illustrative of the technical solutions of this application and are not intended to limit it. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way.

Claims

1. A battery cell, characterized by, include: The outer casing, wherein one of the casing walls is a pre-defined casing wall; Electrode terminals are disposed on the housing; An electrode assembly is located inside the housing and electrically connected to the electrode terminals, and the arrangement direction of the preset housing wall and the electrode assembly is a first direction; A pressure relief mechanism is provided on the preset shell wall; An insulating element is located between the preset shell wall and the electrode assembly. The insulating element has multiple vent holes. The insulating element includes a main body and a boss connected to each other. The boss is located between the main body and the electrode assembly along the first direction. The vent hole formed in the main body is a first vent hole. Along the first direction, the projection area of ​​the first vent hole is located within the projection area of ​​the pressure relief mechanism.

2. The battery cell of claim 1, wherein, The battery cell has an injection hole that penetrates the preset shell wall and the insulating member. The injection hole and the pressure relief mechanism are arranged in a second direction, which is intersected with the first direction. Part of the first vent hole is located on the side of the boss facing the injection hole along the second direction.

3. The battery cell of claim 2, wherein, The boss is positioned across the opposite sides of the pressure relief mechanism along a third direction, which intersects with the first direction and the second direction, respectively.

4. The battery cell of claim 2, wherein, Part of the first vent hole is located on the side of the boss away from the injection hole along the second direction.

5. The battery cell according to claim 2, characterized in that, The boss has an exhaust chamber, the projection area of ​​the exhaust chamber along the first direction at least partially overlaps with the projection area of ​​the pressure relief mechanism along the first direction, the chamber walls on opposite sides along the second direction are first walls, the exhaust holes formed on the first walls are second exhaust holes communicating with the exhaust chamber, and the first wall of the exhaust chamber facing the injection hole has the second exhaust hole.

6. The battery cell of claim 5, wherein, The number of the second exhaust holes is at least one, and a projection area of each of the second exhaust holes along an axial direction of the corresponding second exhaust hole is 14mm 2 ~ 22mm 2 .

7. The battery cell of claim 5, wherein, The number of second exhaust holes on at least one side of the first wall is multiple, and the directions of the multiple second exhaust holes are arranged in a way that intersects with the first direction and the second direction respectively. Along the direction of the multiple second exhaust holes arranged in a way that the distance between two adjacent second exhaust holes is 2.5mm to 4mm.

8. The battery cell of claim 5, wherein, The cavity wall of the exhaust chamber facing the electrode assembly along the first direction is the second wall, and the exhaust hole formed on the second wall is the third exhaust hole communicating with the exhaust chamber.

9. The battery cell of claim 8, wherein, The maximum length of the projection area formed by the axial projection of each exhaust hole is a preset length. The preset length of the third exhaust hole is greater than the preset length of the second exhaust hole, and the preset length of the second exhaust hole is greater than the preset length of the first exhaust hole.

10. The battery cell of claim 8, wherein, The number of the third exhaust holes is at least one, and a projection area of each of the third exhaust holes along an axial direction of the corresponding third exhaust hole is 40mm 2 ~ 50mm 2 .

11. The battery cell of claim 8, wherein, There are multiple third exhaust holes, and the arrangement directions of the multiple third exhaust holes are respectively intersecting the first direction and the second direction. Along the arrangement directions of the multiple third exhaust holes, the distance between two adjacent third exhaust holes is 2.5mm to 4mm.

12. The battery cell of claim 8, wherein, The second wall is located between the two first walls along the second direction. The second wall is located on the side of the main body facing the electrode assembly along the first direction. Each first wall is connected to the second wall and the corresponding main body. The projection area of ​​the second wall is arranged at intervals with the projection area of ​​the main body along the first direction.

13. The battery cell of claim 8, wherein, The second wall includes two sub-walls spaced apart along the second direction, at least one of the sub-walls being provided with the second vent hole, and the distance between the two sub-walls along the second direction is 1mm to 5mm.

14. The battery cell according to any one of claims 1 to 13, characterized in that The number of the first exhaust holes is at least one, and a projection area of each of the first exhaust holes along an axial direction of the corresponding first exhaust hole is 10mm 2 ~ 14mm 2 .

15. The battery cell according to any one of claims 1 to 13, characterized in that, Along the first direction, the projected area of ​​the pressure relief mechanism is 780 mm². 2 ~950mm 2 ; and / or, the projected area of ​​each of the exhaust holes along the axial direction of the corresponding exhaust hole is a preset area, and the sum of the preset areas of all the exhaust holes is 1000 mm. 2 ~1200mm 2 .

16. The battery cell according to any one of claims 1 to 13, characterized in that, The projection area of ​​the boss is at least partially located within the projection area of ​​the pressure relief mechanism.

17. A battery device characterized by comprising: Includes the battery cell according to any one of claims 1 to 16.

18. An electrical device, comprising: Includes a battery cell according to any one of claims 1 to 15 or a battery device according to claim 17, wherein the battery cell or the battery device is used to store or provide electrical energy.

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