Battery monomer, battery and electric device

Abstract

The invention discloses a single battery, a battery and a power utilization device, the single battery comprises a battery cell assembly and a battery shell, the battery shell comprises a cover plate assembly, the cover plate assembly comprises a cover plate, and a positive pole and a negative pole arranged on the cover plate, a liquid injection port and an exhaust port are formed in the cover plate, and the liquid injection port and the exhaust port are arranged along the width direction of the cover plate. The liquid injection port and the exhaust port are formed in the center line area of the cover plate; and along the length direction of the cover plate, the liquid injection port and the exhaust port are respectively arranged between the positive pole and the negative pole. After air in the battery monomer is exhausted from the exhaust port, the flowing and infiltration resistance of the electrolyte is reduced, the electrolyte can smoothly circulate between the liquid injection port and the exhaust port, namely the central area of the battery monomer, and the area is relatively well infiltrated.

Description

Technical Field

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

[0002] With the development of secondary battery technologies such as lithium-ion batteries, secondary batteries are widely used in energy storage systems such as hydropower, thermal power, wind power and solar power plants, as well as in many fields such as power tools, electric bicycles, electric motorcycles, electric cars, and aerospace.

[0003] With the increasing demand for lithium battery capacity, more and more lithium battery products are adopting high-capacity systems such as high-nickel + silicon. High-capacity systems have low electrolyte filling coefficients, which leads to insufficient electrolyte wetting and affects battery performance. Summary of the Invention

[0004] In view of the above problems, this application provides a battery cell, a battery, and an electrical device that can solve the problem of insufficient electrolyte wetting during the electrolyte injection process.

[0005] In a first aspect, this application provides a battery cell, including a cell assembly and a battery casing. The battery casing includes a cover assembly, which includes a cover and a positive electrode post and a negative electrode post disposed on the cover. The cover has an injection port and an exhaust port, wherein the injection port and the exhaust port are both located in the centerline region of the cover along the width direction of the cover; and the injection port and the exhaust port are both located between the positive electrode post and the negative electrode post along the length direction of the cover.

[0006] The technical solution of this application embodiment establishes airflow communication between the injection port and the vent port between the positive and negative electrode posts. During the injection process, the injection port injects and pressurizes the battery cell, while the gas inside the battery cell can be smoothly discharged through the vent port. After the air inside the battery cell is discharged through the vent port, the resistance to electrolyte flow and wetting decreases, allowing the electrolyte to flow smoothly between the injection port and the vent port, i.e., in the central region of the battery cell, and achieving good wetting of this region.

[0007] In some embodiments, along the length of the cover plate, the injection port and the vent port are respectively located on both sides of the centerline of the cover plate. The center of the battery cell is located between the injection port and the vent port, and the airflow channel formed by the injection port and the vent port covers the center of the battery cell, ensuring the injection and wetting of the central area of ​​the battery cell.

[0008] In some embodiments, the electrolyte inlet is located on the side away from the negative electrode post. This prevents electrolyte from splashing onto the negative electrode post during injection, thus avoiding contamination and corrosion.

[0009] In some embodiments, the ratio of the distance from the center of the injection port to the first short side of the cover plate to the length of the cover plate is 0.15-0.45, and the ratio of the distance from the center of the vent port to the second short side of the cover plate to the length of the cover plate is 0.15-0.45; along the length direction of the cover plate, the ratio of the distance from the center of the injection port to the center of the vent port to the length of the cover plate is 0.15-0.6. Defining the positions of the injection port and vent port along the length direction of the cover plate ensures that the airflow channel formed by the injection port and vent port wets the central region of the battery cell during injection.

[0010] In some embodiments, the ratio of the distance from the center of the injection port to the first long side of the cover plate to the width of the cover plate is 0.4-0.6, and the ratio of the distance from the center of the vent port to the first long side of the cover plate to the width of the cover plate is also 0.4-0.6. By defining the positions of the injection port and the vent port in the width direction of the cover plate, it is ensured that the injection port and the vent port are located in the central region of the cover plate in the width direction, achieving a better wetting effect on the central region of the battery cell during the injection process.

[0011] In some embodiments, the opening area of ​​the vent is larger than the opening area of ​​the injection port. During the injection process, air inside the battery cell can be smoothly discharged, preventing the formation of high pressure inside the battery cell, which would affect the flow and wetting of the electrolyte.

[0012] In some embodiments, the ratio of the opening area of ​​the vent to the opening area of ​​the injection port is ≤10. If the opening area of ​​the vent is too large, it will increase the difficulty of sealing.

[0013] In some embodiments, multiple vents are formed on the cover plate, and all the vents are located on the same side of the centerline in the width direction of the cover plate. By providing multiple vents, the total area of ​​the vents is increased without increasing the difficulty of sealing the vents, resulting in smoother venting and thus smoother liquid injection and wetting.

[0014] In some embodiments, an explosion-proof valve is provided on the cover plate, and a gap is provided between the exhaust port and the explosion-proof valve. The exhaust port and the explosion-proof valve are separated by a certain distance to prevent the airflow from forcing open the explosion-proof valve during the exhaust process.

[0015] In some embodiments, the cover plate is provided with a pressure relief port, and an explosion-proof valve is provided at the pressure relief port for sealing the pressure relief port, thus forming an exhaust port. During the liquid injection process, the pressure relief port serves as an exhaust port. After the liquid injection is completed, the pressure relief port is sealed with the explosion-proof valve, reducing the need for exhaust ports. This reduces the work of opening and sealing exhaust ports and increases the consistency and sealing performance of the cover plate.

[0016] Secondly, this application provides a battery, including the battery cell in the above embodiments, and also including a casing and a battery management system.

[0017] Thirdly, this application provides an electrical device including the battery in the above embodiments, the battery being used to provide electrical energy.

[0018] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0019] 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:

[0020] Figure 1 This is a schematic diagram of the vehicle structure according to some embodiments of this application;

[0021] Figure 2 Exploded structural diagrams of battery cells according to some embodiments of this application;

[0022] Figure 3 This is a first-view structural schematic diagram of a battery cell according to some embodiments of this application;

[0023] Figure 4 This is a first-view structural schematic diagram of a battery cell according to some embodiments of this application;

[0024] Figure 5 This is a first-view structural schematic diagram of a battery cell according to some embodiments of this application.

[0025] The reference numerals in the detailed embodiments are as follows:

[0026] 1000, vehicles;

[0027] 100. Battery; 200. Controller; 300. Motor;

[0028] 10. Battery cells;

[0029] 11. Battery cell assembly;

[0030] 111. Bare battery cell; 112. Insulating sheet; 113. Adhesive; 114. Adapter plate;

[0031] 12. Battery casing;

[0032] 121. Cover plate assembly; 1210. Cover plate; 1211. Injection port; 1212. Vent port; 1213. Sealing pin; 1214. Negative electrode post; 1215. Positive electrode post; 1216. Explosion-proof valve;

[0033] 122. Aluminum casing;

[0034] 123. Base support. Detailed Implementation

[0035] 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.

[0036] 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 pertains; 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 specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0037] In the description of the embodiments of this application, technical terms such as "first" and "second" 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.

[0038] 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.

[0039] 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 have an "or" relationship.

[0040] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0041] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0042] 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. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0043] Currently, judging from market trends, the application of power batteries is becoming increasingly widespread. Power batteries are not only used in energy storage systems such as hydropower, thermal power, wind power, and solar power plants, but also extensively used in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. With the continuous expansion of power battery applications, market demand is also constantly increasing.

[0044] In this application, the battery cell may include lithium-ion secondary battery cell, lithium-ion primary battery cell, lithium-sulfur battery cell, sodium lithium-ion battery cell, sodium-ion battery cell, or magnesium-ion battery cell, etc., and the embodiments of this application are not limited thereto.

[0045] The battery mentioned in this application refers to a single physical module comprising one or more battery cells to provide higher voltage and capacity. For example, the battery mentioned in this application may include a battery module or a battery, etc. A battery generally includes a casing for encapsulating one or more battery cells. The casing can prevent liquids or other foreign matter from affecting the charging or discharging of the battery cells.

[0046] The electrolyte injection process is a crucial step in battery manufacturing, as the degree of electrolyte penetration directly affects the cycle performance, safety performance, and consistency of lithium-ion batteries.

[0047] With the increasing demand for lithium-ion battery capacity, more and more lithium battery products are adopting high-capacity systems such as high-nickel + silicon. On the one hand, with the volume of a single battery cell remaining constant, the amount of electrolyte injected into the cell is also basically fixed. However, by adopting high-capacity systems such as high-nickel + silicon, the capacity of the single battery cell increases, thus reducing the electrolyte injection coefficient. On the other hand, high-capacity systems with high-nickel + silicon have a short battery life. Therefore, the amount of electrolyte required during the battery's lifespan is reduced accordingly, which also leads to a low electrolyte injection coefficient for high-capacity systems with high-nickel + silicon.

[0048] Bare cells are formed through winding or stacking. After being encapsulated in a battery casing, the gap between the edge of the bare cell and the battery casing is relatively large, while the gap inside the bare cell is smaller, and the gap becomes smaller closer to the center of the bare cell. During the electrolyte filling process, the electrolyte first fills the gap between the bare cell and the battery casing. Because the gap inside the bare cell, especially in the central area, is small, the electrolyte needs a certain amount of time to fill the gap inside the bare cell and achieve complete wetting.

[0049] In existing technologies, each battery cell has only one electrolyte injection hole. During the electrolyte injection process, the internal air pressure of the battery cell increases, and the electrolyte flow is obstructed, making it difficult for the electrolyte to wet the inside of the bare cell, especially the central area. This results in insufficient wetting of the bare cell by the electrolyte, affecting the use of the battery.

[0050] To overcome the above problems, this application provides a battery cell, including a cell assembly and a battery casing. The battery casing includes a cover assembly, which includes a cover plate and positive and negative terminals disposed on the cover plate. An injection port and an vent are formed on the cover plate. Along the width direction of the cover plate, both the injection port and the vent are located in the centerline region of the cover plate; along the length direction of the cover plate, the injection port and the vent are respectively located between the positive and negative terminals. An airflow is formed between the injection port and the vent between the positive and negative terminals. During the injection process, the injection port injects liquid and pressurizes the battery cell, while the gas inside the battery cell can be smoothly discharged through the vent. After the air inside the battery cell is discharged through the vent, the resistance to electrolyte flow and wetting decreases, allowing the electrolyte to flow smoothly between the injection port and the vent, i.e., in the central region of the battery cell, and achieving good wetting of this region.

[0051] The battery cells disclosed in this application can be used, but are not limited to, in electrical devices such as vehicles, ships, or aircraft. Battery modules and batteries incorporating the specifications disclosed in this application can be used to improve battery safety.

[0052] This application provides an electrical device that uses a battery as a power source. The electrical device can be, but is 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.

[0053] For ease of explanation, the following embodiments will be described using a vehicle 1000 as an example of an electrical device according to an embodiment of this application.

[0054] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of a vehicle 1000 provided in some embodiments of this application. The vehicle 1000 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. A battery 100 is disposed inside the vehicle 1000, and the battery 100 can be located at the bottom, front, or rear of the vehicle 1000. The battery 100 can be used to power the vehicle 1000; for example, the battery 100 can serve as the operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery 100 to supply power to the motor 300, for example, to meet the power needs of the vehicle 1000 during startup, navigation, and driving.

[0055] In some embodiments of this application, the battery 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.

[0056] According to some embodiments of this application, refer to Figure 2 and Figure 3 This application provides a battery cell 10, including a cell assembly 11 and a battery casing 12. The battery casing 12 includes a cover assembly 121, which includes a cover 1210 and a positive electrode post 1215 and a negative electrode post 1214 disposed on the cover 1210. The cover 1210 has an injection port 1211 and an exhaust port 1212. Along the width direction of the cover 1210, the injection port 1211 and the exhaust port 1212 are both disposed in the center line region of the cover 1210. Along the length direction of the cover 1210, the injection port 1211 and the exhaust port 1212 are both disposed between the positive electrode post 1215 and the negative electrode post 1214.

[0057] This application uses a square-shell battery as an example for illustration. The cover plate 1210 of the square-shell battery is a rectangular top cover.

[0058] The battery cell assembly 11 includes a bare battery cell 111, an insulating sheet 112, an adhesive tape 113, and an adapter plate 114. The bare battery cell 111 can be a wound cell or a stacked cell, which is not limited here. The insulating sheet 112 wraps around the outer periphery of the bare battery cell 111, insulating the bare battery cell 111 from the battery casing 12. The adhesive tape 113 serves to fix the insulating sheet 112 and protect the bare battery cell 111. The adapter plate 114 is used to electrically connect the tabs of the bare battery cell 111 to the positive terminal 1215 and the negative terminal 1214. Specifically, the adapter plate 114 located at the positive terminal of the bare battery cell is welded to the positive terminal, and the adapter plate 114 located at the negative terminal of the bare battery cell is welded to the negative terminal.

[0059] The battery casing 12 includes an aluminum shell 122, a cover assembly 121, and a base 123. The aluminum shell 122 covers the periphery of the cell assembly 11. The base 123 is located at the bottom of the individual battery cell 10, supporting the cell assembly 11 and sealing the bottom of the battery casing 12. The cover assembly 121 covers and seals the top of the aluminum shell 122. The aluminum shell 122, the base 123, and the cover assembly 121 together form a closed space for accommodating the cell assembly 11 and the electrolyte.

[0060] The cover plate assembly 121 includes a cover plate 1210, a positive terminal 1215, and a negative terminal 1214. The cover plate 1210 is the carrier for the two terminals. The positive terminal 1215 passes through the cover plate 1210. The portion of the positive terminal 1215 located inside the battery cell 10 is welded to the adapter piece 114 at the positive terminal tab of the bare cell 111. The portion of the negative terminal 1214 located inside the battery cell 10 is welded to the adapter piece 114 at the negative terminal tab of the bare cell 111. The portions of the positive terminal 1215 and the negative terminal 1214 located outside the battery cell 10 are both connected to the busbar.

[0061] The electrolyte inlet 1211 is a through hole formed in the cover plate 1210, connecting the interior of the battery cell 10 to the outside. During electrolyte injection, the injection nozzle of the injection device connects to the electrolyte inlet 1211 to inject electrolyte into the battery cell 10. A sealing pin 1213 is provided at the electrolyte inlet 1211, which blocks the inlet 1211 when not being injected. Similarly, the vent 1212 is also a through hole formed in the cover plate 1210, connecting the interior of the battery cell 10 to the outside. During electrolyte injection, the pressure inside the battery cell 10 increases, forcing the gas inside the battery cell 10 to be discharged through the vent 1212, maintaining pressure balance inside the battery cell 10. A sealing pin 1213 is provided at the vent 1212, which blocks the vent 1212 when not being injected.

[0062] During the electrolyte injection process, the injection port 1211 and the vent port 1212 are opened simultaneously. The injection nozzle of the injection equipment connects to the injection port 1211 to inject electrolyte and pressurize the inside of the battery cell 10. As the electrolyte is injected into the battery cell 10, the air originally inside the battery cell 10 is expelled from the vent port, maintaining the pressure balance inside the battery cell 10 and allowing the electrolyte to circulate better within the battery cell 10. After the electrolyte injection is completed, the vent port 1212 is first sealed with a sealing pin 1213. The injection equipment continues to inject electrolyte and pressurize the battery cell 10, and then the injection port 1211 is sealed with a sealing pin 1213. In this way, after the electrolyte injection is completed, the battery cell 10 maintains a positive pressure state, accelerating the wetting of the bare cell 111 by the electrolyte.

[0063] The cover plate 1210 of the square-shell battery is a rectangular cover plate, which includes two long sides and two short sides. The extension direction of the long sides is the length direction of the cover plate 1210, and the extension direction of the short sides is the width direction of the cover plate 1210. The center line along the width direction of the cover plate 1210, which is the line connecting the midpoints of the two short sides of the cover plate 1210, divides the cover plate 1210 in two, and the position of the center line is the center in the width direction. Along the length direction of the cover plate 1210, the positive electrode post 1215 and the negative electrode post 1214 are respectively located near the two ends. The liquid injection port 1211 and the vent port 1212 are both located between the positive electrode post 1215 and the negative electrode post 1214, that is, the liquid injection port 1211 and the vent port 1212 are both located in the region near the center in the length direction. Thus, whether along the length or width of the cover plate 1210, the liquid injection port 1211 and the vent port 1212 are located in the area near the center of the cover plate 1210, and the central area of ​​the cover plate 1210 corresponds to the central area of ​​the battery cell 10. During the liquid injection process, the airflow formed between the liquid injection port 1211 and the vent port 1212 flows through the central area of ​​the battery cell 10, and the electrolyte also penetrates this area better, forming a better wetting effect on this area.

[0064] An airflow is created between the injection port 1211 and the vent port 1212 located between the positive electrode post 1215 and the negative electrode post 1214. During the injection process, the injection port 1211 injects electrolyte and pressurizes the inside of the battery cell 10, while the gas inside the battery cell 10 can be smoothly discharged through the vent port 1212. After the air inside the battery cell 10 is discharged through the vent port 1212, the resistance to electrolyte flow and wetting decreases, allowing the electrolyte to flow smoothly between the injection port 1211 and the vent port 1212, i.e., in the central region of the battery cell 10, and achieving good wetting of this region.

[0065] According to some embodiments of this application, optionally, please continue to refer to Figure 2 and Figure 3Along the length of the cover plate 1210, the injection port 1211 and the vent port 1212 are respectively located on both sides of the center line of the cover plate 1210.

[0066] The centerline of the cover plate 1210 along its length, which is the line connecting the midpoints of the two long sides of the cover plate 1210, is also the center of the battery cell 10 along its length. Because the airflow passage formed between the liquid injection port 1211 and the vent port 1212 needs to cover the center of the battery cell 10, the liquid injection port 1211 and the vent port 1212 need to be located on both sides of the centerline of the cover plate 1210 along its length.

[0067] The center of the battery cell 10 is located between the liquid injection port 1211 and the vent port 1212. The airflow channel formed by the liquid injection port 1211 and the vent port 1212 covers the center of the battery cell 10, ensuring liquid injection and wetting of the central area of ​​the battery cell 10.

[0068] Optionally, please refer to some embodiments of this application as well. Figures 2 to 5 The injection port 1211 is located on the side away from the negative electrode post 1214.

[0069] The negative electrode current collector of bare cell 111 is made of copper; therefore, the negative electrode tab of bare cell 111 is a copper tab. To reduce the weight of the battery cell 10, the terminals of the battery cell 10 are all made of aluminum. Therefore, the connection between the negative electrode terminal 1214 and the negative electrode tab is a copper-aluminum weld, forming a copper-aluminum composite material. This copper-aluminum composite material is more susceptible to corrosion than a single material, and corrosion of the terminal can lead to abnormal voltage. The electrolyte is a corrosive liquid; therefore, during the electrolyte filling process, splashing of electrolyte onto the negative electrode terminal should be avoided.

[0070] The electrolyte inlet 1211 is positioned away from the negative electrode post 1214 to prevent electrolyte from splashing onto the negative electrode post 1214 during electrolyte injection, thus preventing contamination and corrosion of the negative electrode post 1214.

[0071] According to some embodiments of this application, alternatively, please also refer to... Figure 2 and Figure 3 The ratio of the distance between the center of the injection port 1211 and the first short side of the cover plate 1210 to the length of the cover plate 1210 is 0.15-0.45; the ratio of the distance between the center of the vent port 1212 and the second short side of the cover plate 1210 to the length of the cover plate 1210 is 0.15-0.45; along the length direction of the cover plate 1210, the ratio of the distance between the center of the injection port 1211 and the center of the vent port 1212 to the length of the cover plate 1210 is 0.15-0.6.

[0072] To match the injection nozzle of the injection device, the injection port 1211 is a circular opening, with the center of the injection port 1211 being the center of the opening. The vent port 1212 is also a circular opening, with the center of the vent port 1212 being the center of the opening.

[0073] The cover plate 1210 is a rectangular plate. The first short side of the cover plate 1210 is the short side near the injection port 1211, and the second short side of the cover plate is the short side near the vent port 1212.

[0074] The above-mentioned limitations on the distance from the injection port 1211 to the first short side of the cover plate 1210, the distance from the vent port 1212 to the second short side of the cover plate 1210, and the distance between the injection port 1211 and the vent port 1212 must be satisfied simultaneously.

[0075] The positions of the injection port 1211 and the vent port 1212 along the length of the cover plate are defined to ensure that the airflow channel formed by the injection port and the vent port wets the central area of ​​the battery cell during injection.

[0076] According to some embodiments of this application, optionally, please continue to refer to Figure 2 and Figure 3 The ratio of the distance between the center of the injection port 1211 and the first long side of the cover plate 1210 to the width of the cover plate 1210 is 0.4-0.6, and the ratio of the distance between the center of the vent port 1212 and the first long side of the cover plate 1210 to the width of the cover plate 1210 is 0.4-0.6.

[0077] The first long side of the cover plate 1210 is one of the long sides of the rectangular plate, and the width of the cover plate 1210 is the length of the short side of the rectangular plate. The ratio of the distance from the center of the injection port 1211 to the first long side of the cover plate 1210 to the width of the cover plate 1210 is 0.4-0.6. That is, the center of the injection port 1211 is not necessarily located on the center line of the cover plate 1210 in the width direction, but is limited to a range near the center line along the width direction. The range is 1 / 10 of the width direction of the cover plate 1210. Similarly, the vent port 1212 is also located within a 1 / 10 range near the center line of the cover plate 1210 in the width direction.

[0078] It should be noted that the injection port 1211 and the vent port 1212 do not need to be set on the same straight line along the length of the cover plate 1210.

[0079] The positions of the liquid injection port 1211 and the vent port 1212 in the width direction of the cover plate 1210 are defined to ensure that the liquid injection port 1211 and the vent port 1212 are in the central area of ​​the width direction of the cover plate 1210, so that the central area of ​​the battery cell 10 can be well wetted during the liquid injection process.

[0080] According to some embodiments of this application, optionally, the opening area of ​​the vent 1212 is larger than the opening area of ​​the injection port 1211.

[0081] Both the vent 1212 and the injection port 1211 are circular holes. The opening area of ​​the vent 1212 is larger than that of the injection port 1211, meaning that the diameter of the vent 1212 is larger than that of the injection port 1211.

[0082] When a certain amount of electrolyte is injected through the injection port 1211, a corresponding amount of gas needs to be discharged through the vent port. If the diameter of the vent port 1212 is less than or equal to the diameter of the injection port 1211, the gas will not be discharged smoothly during the injection process, causing the gas to accumulate inside the battery cell 10. The gas pressure inside the battery cell 10 increases, affecting the flow and wetting of the electrolyte inside the battery cell 10, especially in the central area.

[0083] During the electrolyte injection process, the air inside the battery cell 10 can be smoothly discharged, and high pressure will not be formed inside the battery cell 10, thus affecting the flow and wetting of the electrolyte.

[0084] According to some embodiments of this application, optionally, the ratio of the opening area of ​​the vent 1212 to the opening area of ​​the injection port 1211 is ≤10.

[0085] The diameter of the injection port 1211 is fixed. Generally, the diameter of the injection port 1211 is 3mm. If the diameter of the vent port 1212 is too large, the welding cost and difficulty will increase.

[0086] The diameter of the pole post is generally 30mm. The diameter of the exhaust port 1212 is generally not larger than the diameter of the pole post. If it is larger than the diameter of the pole post, not only will the difficulty increase and the welding cost increase, but it will also reach the boundary of the width direction of the cover plate 1210, affecting the sealing of the exhaust port 1212.

[0087] According to some embodiments of this application, optionally, a plurality of exhaust ports 1212 are formed on the cover plate 1210, and the plurality of exhaust ports 1212 are all disposed on the same side of the center line in the width direction of the cover plate 1210.

[0088] Multiple vents 1212 are provided, which increases the total area of ​​the vents 1212 without increasing the difficulty of sealing them, making venting smoother and thus making liquid injection and wetting smoother.

[0089] According to some embodiments of this application, optionally, please refer to... Figure 4 The cover plate 1210 is equipped with an explosion-proof valve 1216, and there is a gap between the exhaust port 1212 and the explosion-proof valve 1216.

[0090] The cover plate 1210 is equipped with a pressure relief hole, which is covered by an explosion-proof valve 1216. During battery use, if thermal runaway occurs inside the battery cell 10, causing a surge in pressure, the pressure can be released by breaking through the explosion-proof valve 1216, preventing the battery cell 10 from exploding. The explosion-proof valve 1216 is a one-time valve and is rendered unusable after being opened.

[0091] There is a gap between the exhaust port 1212 and the explosion-proof valve 1216, that is, the exhaust port 1212 is not set right next to the explosion-proof valve 1216, so as to avoid the airflow impacting the explosion-proof valve during the exhaust process and causing the explosion-proof valve to be blown open.

[0092] According to some embodiments of this application, optionally, please refer to... Figure 5 The cover plate 1210 is provided with a pressure relief port, and an explosion-proof valve 1216 is provided at the pressure relief port for sealing the pressure relief port, thus forming an exhaust port 1212. During the liquid injection process, the pressure relief port serves as the exhaust port 1212. After the liquid injection is completed, the pressure relief port is sealed with the explosion-proof valve 1216, which reduces the need for setting up a separate exhaust port 1212. This reduces the work of opening and sealing the exhaust port 1212, and also increases the consistency and sealing performance of the cover plate 1210.

[0093] According to some embodiments of this application, this application also provides a battery, including a battery cell 10 as described in any of the above embodiments, the battery further including a casing for covering the battery cell 10 and a battery management system for managing the battery.

[0094] According to some embodiments of this application, this application also provides an electrical device including a battery as described in any of the above embodiments, and the battery is used to provide electrical energy to the electrical device.

[0095] The electrical device can be any of the aforementioned battery-powered devices or systems.

[0096] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. 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. 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, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, comprising a cell assembly and a battery casing, the battery casing comprising a cover assembly, the cover assembly comprising a cover plate and a positive electrode post and a negative electrode post disposed on the cover plate, characterized in that, The cover plate has an injection port and an exhaust port, wherein, Along the width direction of the cover plate, both the injection port and the vent port are located in the centerline area of ​​the cover plate; Along the length of the cover plate, both the injection port and the vent are located between the positive electrode post and the negative electrode post.

2. The battery cell as described in claim 1, characterized in that, Along the length of the cover plate, the injection port and the vent port are respectively located on both sides of the center line of the cover plate.

3. The battery cell as described in claim 1, characterized in that, The injection port is located on the side away from the negative electrode post.

4. The battery cell according to any one of claims 1-3, characterized in that, The ratio of the distance from the center of the injection port to the first short side of the cover plate to the length of the cover plate is 0.15-0.45, and the ratio of the distance from the center of the vent port to the second short side of the cover plate to the length of the cover plate is 0.15-0.

45. Along the length of the cover plate, the ratio of the distance between the center of the injection port and the center of the vent port to the length of the cover plate is 0.15-0.

6.

5. The battery cell according to any one of claims 1-4, characterized in that, The ratio of the distance from the center of the injection port to the first long side of the cover plate to the width of the cover plate is 0.4-0.6, and the ratio of the distance from the center of the vent port to the first long side of the cover plate to the width of the cover plate is 0.4-0.

6.

6. The battery cell according to any one of claims 1-5, characterized in that, The opening area of ​​the vent is larger than the opening area of ​​the injection port.

7. The battery cell as described in claim 6, characterized in that, The ratio of the opening area of ​​the vent to the opening area of ​​the injection port is ≤10.

8. The battery cell according to any one of claims 1-6, characterized in that, Multiple exhaust ports are formed on the cover plate, and all of the exhaust ports are located on the same side of the center line in the width direction of the cover plate.

9. The battery cell according to any one of claims 1-6, characterized in that, The cover plate is equipped with an explosion-proof valve, and there is a gap between the exhaust port and the explosion-proof valve.

10. The battery cell as described in claim 1, characterized in that, The cover plate is provided with a pressure relief port, and an explosion-proof valve for sealing the pressure relief port is provided at the pressure relief port, and the pressure relief port forms the exhaust port.

11. A battery, characterized in that, The battery includes a battery cell as described in any one of claims 1-10, and the battery further includes a casing and a battery management system.

12. An electrical appliance, characterized in that, Includes the battery as described in claim 11, the battery being used to provide electrical energy.

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