Cover plate assembly, battery casing, battery and electrical device

Abstract

The embodiments of the present disclosure relate to the technical field of batteries. Provided are a cover plate assembly, a battery casing, a battery and an electrical device. The cover plate assembly comprises a cover plate, a terminal post, a spacer ring, an insulating ring, a transition ring and a sealing member. The cover plate is provided with a through hole; a portion of the terminal post passes through the through hole; the spacer ring surrounds the outer periphery of the terminal post; the insulating ring surrounds the outer periphery of the terminal post and is spaced apart from the spacer ring along the extension direction of the terminal post; the sealing member surrounds the outer periphery of the terminal post; along the extension direction of the terminal post, two sides of the sealing member respectively and sealingly abut against the spacer ring and the insulating ring; the transition ring surrounds the side of the sealing member facing away from the terminal post and is located between the spacer ring and the insulating ring. When the terminal post is energized, the sealing member physically isolates the terminal post from the transition ring, so as to effectively prevent electrical conduction between the terminal post and the transition ring, thus preventing the cover plate and the battery casing from being energized and improving battery safety.

Description

Cover plate assembly, battery casing, battery and electrical equipment

[0001] This disclosure claims priority to Chinese Patent Application No. 202510121048.6, filed on January 23, 2025, entitled “Cover Assembly, Battery Housing, Battery and Electrical Device”, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This disclosure relates to the field of battery technology, and in particular to a cover plate assembly, a battery casing, a battery, and an electrical device. Background Technology

[0003] Battery performance directly affects key indicators of electrical devices such as electric vehicles, including driving range, acceleration performance, and charging time.

[0004] In related technologies, a battery includes a casing, a cell, terminals, and a cover assembly. The casing protects the cell from physical damage and leakage. The cell is responsible for storing and releasing electrical energy. The cell includes a positive electrode, a negative electrode, a separator, and an electrolyte. The electrolyte allows ions to move between the positive and negative electrodes, thereby completing the electrochemical reaction. The cover assembly seals the casing, which has openings. The current generated by the electrochemical reaction inside the cell is conducted to the terminals, which then lead the current out of the battery and connect it to an external circuit.

[0005] However, existing cover plate assemblies have the problem of electrical conduction between the pole and the cover plate assembly, resulting in the cover plate assembly and the housing being electrified. Summary of the Invention

[0006] This disclosure provides a cover plate assembly, a battery casing, a battery, and an electrical device, which prevents electrical conduction between the cover plate assembly and the terminal post, avoids the cover plate assembly and the battery casing from becoming energized, and improves the safety of the electrical device.

[0007] In a first aspect, embodiments of this disclosure provide a cover assembly. The cover assembly is used for a battery. The cover assembly includes:

[0008] Cover plate with through holes;

[0009] Terminal post, some of which have through holes;

[0010] A spacer ring, encircling the outer perimeter of the pole;

[0011] An insulating ring is placed around the outer periphery of the pole post and spaced apart along the extension direction of the pole post.

[0012] A sealing element surrounds the outer periphery of the pole post; along the extension direction of the pole post, the two sides of the sealing element respectively seal against the spacer and the insulating ring;

[0013] The transition ring surrounds the side of the seal away from the pole and is located between the spacer and the insulating ring.

[0014] In some embodiments of this disclosure, a first gap exists between the seal and the pole.

[0015] In some embodiments of this disclosure, a second gap is formed between the seal and the transition ring.

[0016] In some embodiments of this disclosure, a transition ring is connected to a cover plate.

[0017] In some embodiments of this disclosure, when there is a first gap between the seal and the pole post, the seal is annular, and the first gap is formed between the inner circumferential side of the seal and the outer circumferential side of the pole post.

[0018] In some embodiments of this disclosure, the inner diameter n of the seal is greater than the diameter a of the pole.

[0019] In some embodiments of this disclosure, when a second gap is formed between the seal and the transition ring, a second gap is formed between the inner circumferential side of the transition ring and the outer circumferential side of the seal.

[0020] In some embodiments of this disclosure, the outer diameter m of the seal is smaller than the inner diameter b of the transition ring.

[0021] In some embodiments of this disclosure, the seal, spacer, and insulating ring are interference-fitted along the thickness direction of the cover plate.

[0022] In some embodiments of this disclosure, a first sealing groove is provided on the side of the seal near the pole post, and a first gap is formed between the inner wall of the first sealing groove and the pole post.

[0023] In some embodiments of this disclosure, the portion of the pole near the seal has a pole groove; a first gap is formed between the inner wall of the pole groove and the seal.

[0024] In some embodiments of this disclosure, the first sealing groove includes a first sub-groove and a second sub-groove, the first sub-groove and the second sub-groove being centrally symmetrical about the center of the sealing element.

[0025] Along the radial direction of the seal, passing through the center of the seal, the length p1 of the line connecting the bottom of the first sub-groove and the bottom of the second sub-groove is greater than the diameter a of the pole post.

[0026] In some embodiments of this disclosure, the pole post groove includes a first sub-pole post groove and a second sub-pole post groove, the first sub-pole post groove and the second sub-pole post groove being centrally symmetrical about the center of the seal.

[0027] Along the radial direction of the seal, passing through the center of the seal, the length of the line connecting the bottom of the groove of the first sub-pole post and the bottom of the groove of the second sub-pole post is less than the inner diameter of the seal.

[0028] In some embodiments of this disclosure, a second sealing groove is provided on the side of the seal near the transition ring, and a second gap is formed between the inner wall of the second sealing groove and the transition ring.

[0029] In some embodiments of this disclosure, the portion of the transition ring near the seal has a connecting groove; a second gap is formed between the inner wall of the connecting groove and the seal.

[0030] In some embodiments of this disclosure, the second sealing groove includes a third sub-groove and a fourth sub-groove, which are centrally symmetrical about the center of the sealing element.

[0031] Along the radial direction of the seal, passing through the center of the seal, the length p2 of the line connecting the bottom of the third sub-groove and the bottom of the fourth sub-groove is less than the inner diameter b of the transition ring.

[0032] In some embodiments of this disclosure, the connecting groove includes a first sub-connecting groove and a second sub-connecting groove, the first sub-connecting groove and the second sub-connecting groove being centrally symmetrical about the center of the transition ring.

[0033] Along the radial direction of the transition ring, passing through the center of the transition ring, the length of the line connecting the bottom of the first sub-connecting groove and the bottom of the second sub-connecting groove is greater than the outer diameter of the seal.

[0034] Secondly, embodiments of this disclosure provide a battery housing, which includes a housing and a cover assembly.

[0035] The housing has a receiving cavity with an opening at one end, and a cover assembly closes to the opening.

[0036] In some embodiments of this disclosure, the first gap and / or the second gap of the cover plate assembly communicate with the receiving cavity.

[0037] Thirdly, embodiments of this disclosure provide a battery, which includes a battery cell and a battery casing, wherein the battery cell is located in a cavity within the battery casing.

[0038] Fourthly, embodiments of this disclosure provide an electrical device. The electrical device includes a battery.

[0039] This disclosure provides a cover plate assembly, a battery casing, a battery, and an electrical device. The cover plate assembly includes a cover plate, terminals, spacers, an insulating ring, a transition ring, and a seal. The cover plate has a through hole; a portion of the terminals passes through the through hole; the spacers surround the outer periphery of the terminals; the insulating ring surrounds the outer periphery of the terminals and is spaced apart from the spacers along the extension direction of the terminals; the seal surrounds the outer periphery of the terminals; along the extension direction of the terminals, both sides of the seal respectively seal against the spacers and the insulating ring; the transition ring surrounds the side of the seal away from the terminals and is located between the spacers and the insulating ring. After the battery finishes injecting electrolyte, the electrolyte will flow back to the receiving cavity under gravity. The electrolyte will not remain between the terminals and the transition ring. The seal can physically isolate the terminals and the transition ring, avoiding electrical connection between the terminals and the transition ring, preventing the transition ring from becoming charged, and preventing electrical conduction between the terminals and the cover plate assembly, thus improving battery safety. Attached Figure Description

[0040] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure.

[0041] Figure 1 is a schematic diagram of the structure of the battery provided in an embodiment of this disclosure;

[0042] Figure 2 is a schematic diagram of the cover plate assembly provided in an embodiment of this disclosure;

[0043] Figure 3 is a schematic diagram of the cover plate assembly provided in an embodiment of this disclosure.

[0044] Figure 4 is an enlarged view of region A in Figure 3;

[0045] Figure 5 is a structural schematic diagram of the sealing element of the cover plate assembly provided in this disclosure according to one embodiment;

[0046] Figure 6 is a second structural schematic diagram of the sealing element of the cover plate assembly provided in this disclosure according to Embodiment 1;

[0047] Figure 7 is a schematic diagram of the structure of the sealing element of the cover plate assembly provided in this disclosure according to a second embodiment;

[0048] Figure 8 is a second structural schematic diagram of the sealing element of the cover plate assembly provided in this disclosure.

[0049] Figure 9 is a schematic diagram of the structure of the sealing element of the cover plate assembly provided in the second embodiment of this disclosure.

[0050] Explanation of reference numerals in the attached drawings: 100: housing; 200: cover plate; 210: spacer ring; 212: lead-out piece; 220: transition ring; 230: insulating ring; 240: seal; 250: pole; 260: injection hole; 300: first seal groove; 310: second seal groove.

[0051] The accompanying drawings have illustrated specific embodiments of this disclosure, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concepts of this disclosure to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0052] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this disclosure as detailed in the appended claims.

[0053] In related technologies, a cover plate is provided at the opening of the battery casing, and a through hole is provided on the cover plate. The terminal is located at the through hole, so that the terminal leads out the current inside the battery. A connecting ring and a sealing ring are also provided on the cover plate. The connecting ring is used to connect the terminal and the cover plate, and the sealing ring is located between the connecting ring and the terminal to prevent electrolyte leakage.

[0054] Along the extension direction of the cover plate, the sealing ring is set to an interference fit with the pole and the connecting ring to improve the sealing effect of the cover plate and the pole.

[0055] However, during the process of injecting electrolyte into the battery casing, the sealing ring will deform under pressure, and the sealing ring will no longer be in an interference fit with the terminal and connecting ring. This causes the sealing ring to fail to effectively seal the connecting ring and terminal, and the electrolyte will flow into the gap between the terminal and the connecting ring.

[0056] After the electrolyte is injected, the sealing ring no longer deforms. The electrolyte that flowed into the gap will remain in the space formed between the terminal, the connecting ring, and the top of the sealing ring, and cannot flow back into the battery's housing. Since the terminal and the connecting ring are both made of metal, they are electrically conductive. Because the connecting ring is connected to the cover plate, and the cover plate is connected to the battery casing, this will cause the cover plate and the battery casing to become electrified, reducing battery safety.

[0057] In view of this, embodiments of the present disclosure provide a cover plate assembly, a battery casing, a battery, and an electrical device. The cover plate assembly includes a cover plate, terminals, spacers, an insulating ring, a transition ring, and a seal. The cover plate has a through hole; a portion of the terminals passes through the through hole; the spacer surrounds the outer periphery of the terminals; the insulating ring surrounds the outer periphery of the terminals and is spaced apart from the spacer along the extension direction of the terminals; the transition ring surrounds the outer periphery of the terminals and is located between the spacer and the insulating ring; the seal surrounds the outer periphery of the terminals; along the extension direction of the terminals, both sides of the seal seal respectively abut against the spacer and the insulating ring; the transition ring surrounds the side of the seal facing away from the terminals and is located between the spacer and the insulating ring. After the battery finishes injecting electrolyte, the electrolyte will flow back to the receiving cavity under gravity. The electrolyte will not remain between the terminals and the transition ring. The seal can physically isolate the terminals and the transition ring, avoiding electrical connection between the terminals and the transition ring, preventing the transition ring from becoming charged, and preventing electrical conduction between the terminals and the cover plate assembly, thus improving battery safety.

[0058] The technical solutions of this disclosure and how they solve the aforementioned technical problems will be described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of this disclosure will now be described with reference to the accompanying drawings.

[0059] In a first aspect, embodiments of this disclosure provide an electrical device. The electrical device includes a battery. The electrical device can be a vehicle, mobile phone, portable device, laptop computer, ship, spacecraft, electric toy, power tool, etc. This disclosure does not limit the specific type of electrical device.

[0060] Secondly, embodiments of this disclosure provide a battery, which includes a battery cell and a battery casing, wherein the battery cell is located in a cavity within the battery casing.

[0061] The battery 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-cadmium battery, etc. This disclosure does not limit the type of battery.

[0062] Thirdly, referring to FIG1, an embodiment of the present disclosure provides a battery housing, the battery housing including a housing 100 and a cover assembly.

[0063] The housing 100 has a receiving cavity with an opening at one end, and a cover assembly closes to the opening.

[0064] Exemplarily, the housing 100 is a structural part of the battery for housing internal components such as electrodes and electrolyte. The housing 100 possesses mechanical strength and chemical stability to protect the internal components of the battery from the influence of the external environment.

[0065] The cover assembly is used to close the opening portion of the housing 100 and to provide electrical connection and safety functions for the battery.

[0066] As one possible implementation, the first gap of the cover plate assembly is in communication with the receiving cavity so that the electrolyte retained in the first gap can flow back into the receiving cavity.

[0067] As one possible implementation, the second gap of the cover plate assembly communicates with the receiving cavity so that the electrolyte retained in the second gap flows back into the receiving cavity.

[0068] Fourthly, referring to Figures 2 to 4, embodiments of this disclosure provide a cover assembly. The cover assembly is used for a battery. The cover assembly includes:

[0069] Cover plate 200, with through holes;

[0070] The pole post 250 has through holes in some of the pole posts 250.

[0071] Spacer 210 surrounds the outer periphery of pole post 250;

[0072] An insulating ring 230 surrounds the outer periphery of the pole post 250 and is spaced apart from the spacer ring 210 along the extending direction of the pole post 250.

[0073] A seal 240 surrounds the outer periphery of the pole post 250; along the extending direction of the pole post 250, the two sides of the seal 240 respectively seal against the spacer 210 and the insulating ring 230.

[0074] The transition ring 220 surrounds the side of the seal 240 away from the pole post 250 and is located between the spacer ring 210 and the insulating ring 230.

[0075] For example, referring to FIG3, the thickness direction of the cover plate 200 is shown in the Y direction in FIG3. The extension direction of the cover plate 200 is shown in the X direction in FIG3.

[0076] For example, the cover 200 closes to the opening of the battery housing cavity to prevent leakage of electrolyte within the cavity. The cover 200 provides an initial physical barrier for the electrolyte flowing within the cavity to prevent electrolyte leakage.

[0077] Terminal 250 is the interface connecting the battery to an external circuit, responsible for conducting the current generated inside the battery to an external load, or conducting current back into the battery during charging. The materials used for terminal 250 include conductive copper, aluminum, and nickel. This ensures efficient current conduction and minimizes energy loss.

[0078] The cover plate 200 is also provided with an injection hole 260. Electrolyte is injected into the receiving cavity of the battery casing through the injection hole 260.

[0079] For example, the spacer 210 near the insulating ring 230, the transition ring 220 near the pole post 250, the insulating ring 230 near the spacer 210, and the outer periphery of the pole post 250 form an installation area. The seal 240 surrounds the outer periphery of the pole post 250 and is located in the installation area.

[0080] Along the extension direction of the pole post 250, the two sides of the seal 240 respectively seal against the insulating ring 230 and the spacer 210. During the process of injecting electrolyte into the accommodating cavity, under pressure changes, some electrolyte will move towards the cover plate assembly and enter the mounting area. By sealing the seal 240 and the spacer 210 together, and sealing the seal 240 and the insulating ring 230 together, after the electrolyte injection is completed, the seal 240 can physically isolate the terminal post 250 and the transition ring 220 because its two sides are sealed to the insulating ring 230 and the spacer 210 respectively. The electrolyte will not remain between the terminal post 250 and the transition ring 220. When the terminal post 250 is energized, the seal 240 physically isolates the terminal post 250 and the transition ring 220, which can effectively prevent current leakage between the terminal post 250 and the transition ring 220, prevent the transition ring 220 from becoming energized, and prevent electrical conduction between the terminal post 250 and the cover plate assembly, thereby improving battery safety.

[0081] Exemplarily, spacer 210 includes an insulating spacer. The insulating spacer is fitted around the outer periphery of terminal 250. In the battery, terminal 250 is connected to the current collector of the battery and conducts the current transferred from the current collector to terminal 250. By providing spacer 210, spacer 210 is used to physically isolate terminal 250 from the rest of the battery components, preventing short circuits. Spacer 210 can effectively block unintended current paths, avoiding electrical connections within the battery other than the current collector components and terminal 250, thereby ensuring the safety and normal operation of the battery.

[0082] By way of example, the cover plate assembly also includes a lead-out tab 212. The lead-out tab 212 is disposed on the side of the insulating spacer opposite to the cover plate 200. The lead-out tab 212 is used to electrically connect the current collector and the terminal 250. The lead-out tab 212 enables current to be efficiently conducted to the terminal 250.

[0083] Along the thickness direction of the cover plate 200, the upper surface of the lead-out piece 212 abuts against the lower surface of the insulating spacer. The lead-out piece 212 is welded to the terminal post 250 to form an electrical connection.

[0084] The lead 212 is conductive and can be made of copper or aluminum.

[0085] The transition ring 220 is connected to the cover plate 200. The cover plate 200 is provided with a cover plate groove, which communicates with the through hole, and the opening of the cover plate groove faces the through hole. A portion of the transition ring 220 is placed in the cover plate groove. A portion of the transition ring 220 extends out of the cover plate groove in a direction away from the spacer ring 210.

[0086] In some embodiments, the cover plate 200 is a metal plate. The transition ring 220 is also a metal transition ring. The transition ring 220 and the cover plate 200 are welded together. By welding the transition ring 220 and the cover plate 200 together, airtightness is improved, preventing gas or liquid (such as electrolyte) from leaking through the connection between the cover plate 200 and the transition ring 220. Furthermore, the welded connection between the cover plate 200 and the transition ring 220 improves the consistency of the connection area and reduces potential leakage points. In addition, the welded connection between the cover plate 200 and the transition ring 220 improves the connection strength, enabling it to withstand vibrations, impacts, and mechanical stresses that the battery may encounter during use.

[0087] For example, the transition ring 220 can be an aluminum transition ring. The transition ring 220 has the strength and load-bearing capacity to withstand the mechanical stress and impact that the battery may encounter during use. The transition ring 220 is not easily deformed under high load conditions, maintaining the stability and integrity of the cover plate 200 and the transition ring 220.

[0088] Along the thickness direction of the cover plate 200, the insulating ring 230 is located on the side of the transition ring 220 away from the spacer ring 210, and the insulating ring 230 is connected to the pole post 250.

[0089] For example, the insulating ring 230 may be a ceramic ring. The insulating ring 230 has electrical insulation properties. The insulating ring 230 serves to provide electrical insulation and prevent accidental contact between the pole 250 and the cover plate 200 or other conductive parts, thereby avoiding short circuits.

[0090] The insulating ring 230 is located on the side of the cover plate 200 opposite to the battery housing cavity. The bottom of the insulating ring 230 and a portion of the cover plate groove at the extension of the transition ring 220 are brazed together. Brazing creates a continuous metal joint at the connection between the transition ring 220 and the insulating ring 230, improving the sealing performance of the transition ring 220 and the insulating ring 230 and preventing electrolyte leakage. Furthermore, the brazing material flows and fills the gap between the transition ring 220 and the insulating ring 230 during heating, forming a uniform sealing layer between them and reducing potential leakage points. In addition, the brazing connection between the transition ring 220 and the insulating ring 230 improves the connection strength, enabling the connection to withstand vibrations and mechanical stresses that the battery may encounter during use, ensuring long-term connection stability.

[0091] In some embodiments, a metal layer is deposited on the surface of the insulating ring 230, and the transition ring 220 and the insulating ring 230 are connected by the metal layer and solder.

[0092] In other embodiments, a solder containing active elements (such as titanium or zirconium) is used to connect the transition ring 220 and the insulating ring 230.

[0093] Furthermore, the top of the insulating ring 230 and the electrode post 250 are brazed together. The brazing connection between the insulating ring 230 and the electrode post 250 improves the airtightness of the connection point and enhances its sealing performance, preventing electrolyte leakage. Moreover, when the insulating ring 230 and the electrode post 250 are connected using brazing filler metal, the filler metal, upon heating, flows into the connection gap between the insulating ring 230 and the electrode post 250 through capillary action, filling all minute gaps and forming a continuous sealing layer.

[0094] In addition, the insulating ring 230 and the pole post 250 are connected by brazing, which improves the connection strength between the insulating ring 230 and the pole post 250 and reduces the risk of failure at the connection.

[0095] In this way, the spacer 210, transition ring 220, and insulating ring 230 form a complete connection and sealing system, which prevents electrolyte leakage and reduces the possible displacement or loosening of the electrode post 250 during operation.

[0096] As one possible implementation, a first gap exists between the seal 240 and the pole 250.

[0097] During the electrolyte injection process into the receiving cavity, under pressure changes, some electrolyte moves towards the cover assembly and enters the first gap. By setting the first gap between the seal 240 and the terminal 250, after the electrolyte injection is completed, since the first gap is connected to the receiving cavity, the electrolyte located in the first gap will flow back into the receiving cavity under its own gravity, preventing electrical conduction between the terminal 250 and the transition ring 220 and improving battery safety.

[0098] As one possible implementation, a second gap is formed between the seal 240 and the transition ring 220.

[0099] During the electrolyte injection process into the receiving cavity, under pressure changes, some electrolyte moves towards and enters the cover assembly. By providing a second gap between the seal 240 and the transition ring 220, after the electrolyte injection is completed, since the second gap is connected to the receiving cavity, the electrolyte located at the second gap will flow back into the receiving cavity under its own gravity. This prevents the formation of an electrolytic cell between the electrode post 250 and the transition ring 220 through the electrolyte, avoids electrical conduction between the electrode post 250 and the transition ring 220, prevents the battery casing from becoming charged, and improves battery safety.

[0100] As one feasible implementation, referring to Figures 5 and 6, the seal 240 is annular and surrounds the outer periphery of the pole post 250.

[0101] The first gap is formed between the inner peripheral side of the seal 240 and the outer peripheral side of the pole 250.

[0102] For example, the seal 240 is a sealing ring. The annular seal 240 can be evenly distributed on the outer periphery of the pole 250, ensuring that the seal 240 provides consistent sealing performance in all directions.

[0103] The first gap provides a buffer zone for the electrolyte, allowing it to flow in this area and eventually return to the containment cavity, reducing the risk of electrolyte retention.

[0104] For example, the inner circumferential side of seal 240 refers to the surface of seal 240 near the center. For an annular seal 240 (such as an O-ring), the inner circumferential side of seal 240 is the inner diameter portion of annular seal 240.

[0105] The outer periphery of pole post 250 refers to the outer surface of pole post 250.

[0106] In one feasible implementation, the inner diameter *n* of the seal 240 is larger than the diameter *a* of the terminal post 250. This creates a first gap between the inner circumference of the seal 240 and the outer circumference of the terminal post 250, allowing the electrolyte to flow into this gap during electrolyte injection. Since the first gap is connected to the accommodating cavity, after electrolyte injection, the electrolyte flows back into the battery's accommodating cavity under gravity, helping to prevent electrochemical reactions between the terminal post 250 and the transition ring 220 through the electrolyte.

[0107] Conversely, when the inner diameter n of the seal 240 is smaller than the diameter a of the terminal post 250, there is an interference fit between the seal 240 and the terminal post 250. This results in a disconnect between the first gap and the receiving cavity, preventing the electrolyte flowing between the transition ring 220, insulating ring 230, and terminal post 250 during battery filling from flowing back into the receiving cavity. A localized electrolytic cell forms between the transition ring 220 and the terminal post 250 due to the electrolyte. The presence of this electrolytic cell can cause abnormal battery voltage and internal corrosion, seriously affecting battery safety.

[0108] As one possible implementation, when a second gap is formed between the seal 240 and the transition ring 220, a second gap is formed between the inner circumferential side of the transition ring 220 and the outer circumferential side of the seal 240.

[0109] For example, the annular transition ring 220 can be evenly distributed on the outer periphery of the pole post 250 to ensure that every part of the outer periphery of the pole post 250 is surrounded, thereby improving the sealing performance at the connection between the pole post 250 and the cover plate 200.

[0110] The second gap provides a buffer for the electrolyte, allowing it to flow in this area and eventually return to the containment cavity, further reducing the risk of electrolyte retention.

[0111] In one feasible implementation, the outer diameter *m* of the seal 240 is smaller than the inner diameter *b* of the transition ring 220. This creates a second gap between the outer periphery of the seal 240 and the inner periphery of the transition ring 220, allowing the electrolyte to flow into this gap during electrolyte injection. Since the second gap is connected to the receiving cavity, after electrolyte injection, the electrolyte flows back into the battery's receiving cavity under gravity, helping to prevent electrochemical reactions between the electrode post 250 and the transition ring 220 through the electrolyte.

[0112] Conversely, when the outer diameter m of the seal 240 is larger than the inner diameter b of the transition ring 220, there is an interference fit between the seal 240 and the transition ring 220. This results in the second gap not communicating with the receiving cavity, which prevents the electrolyte flowing between the transition ring 220, insulating ring 230, and terminal post 250 during battery filling from flowing back into the receiving cavity. A localized electrolytic cell forms between the transition ring 220 and the terminal post 250 through the electrolyte. The presence of this electrolytic cell can cause abnormal battery voltage, lead to internal corrosion, and seriously affect battery safety.

[0113] As one feasible implementation, the seal 240 is interference-fitted with the spacer 210 and the insulating ring 230 along the thickness direction of the cover plate 200.

[0114] When the seal 240 is not assembled between the transition ring 220 and the pole post, the distance c between the spacer 210 and the insulating ring 230 is less than the height h of the seal 240.

[0115] After the seal 240 is assembled between the transition ring 220 and the terminal post 250, in the thickness direction of the cover plate 200, both ends of the seal 240 are interference-fitted with the spacer 210 and the insulating ring 230. In the extending direction of the cover plate 200, the seal 240 and the terminal post 250 are clearance-fitted, with a first gap between them. The seal 240 and the transition ring 220 are also clearance-fitted. A second gap exists between the seal 240 and the transition ring 220. Thus, along the extending direction of the cover plate 200, the seal 240 forms a physical barrier between the transition ring 220 and the terminal post 250, electrically insulating them and preventing the formation of a galvanic cell between them through the electrolyte.

[0116] Meanwhile, the electrolyte that flows into the mounting area between the electrode post 250 and the transition ring 220 after injection flows back to the accommodating cavity along the first gap and the second gap. It will not remain in the first gap and the second gap and form a local electrolytic cell with the electrode post 250 and the transition ring 220, causing corrosion and thus affecting the battery safety.

[0117] When the terminal 250 is energized, the seal 240 physically isolates the terminal 250 and the transition ring 220, which can effectively prevent current leakage between the terminal 250 and the transition ring 220, thereby avoiding electrical breakdown and improving battery safety.

[0118] An interference fit is a type of mechanical fit where the mating dimensions of two parts are designed to cause interference during assembly; that is, the external dimensions of the parts are slightly larger than the internal dimensions of their mating holes. This type of fit generates a certain amount of pressure or stress after assembly, resulting in a tight contact between the two parts.

[0119] Clearance fit is a mechanical assembly method in which a certain clearance exists between two mating parts. This fit allows the mating parts to move or adjust relatively freely after assembly.

[0120] As one feasible implementation, referring to Figures 7 to 9, a first sealing groove 300 is provided on the side of the seal 240 near the pole post 250, and a first gap is formed between the inner wall of the first sealing groove 300 and the pole post 250.

[0121] In some embodiments, the portion of the inner circumferential side of the seal 240 where the first seal groove 300 is not formed abuts against the pole post 250, and a first gap is formed between the inner wall of the first seal groove 300 and the pole post 250.

[0122] During the process of injecting electrolyte into the accommodating cavity, under pressure changes, some electrolyte will move towards the cover plate assembly, and some electrolyte will flow to the first gap formed between the first sealing groove 300 of the sealing member 240 and the electrode post 250. After the battery finishes injecting electrolyte, since the first gap is connected to the accommodating cavity, the electrolyte located in the first gap will flow back into the accommodating cavity under its own gravity, thus avoiding electrolyte retention in the cover plate assembly and improving the sealing performance of the cover plate assembly.

[0123] For example, there are multiple first sealing grooves 300. Along the circumference of the seal 240, multiple first sealing grooves 300 are spaced apart on the inner circumferential side of the seal 240. In this way, multiple first gaps are formed between the inner walls of the multiple first sealing grooves 300 and the electrode post 250. The arrangement of multiple first gaps provides multiple loop paths for the electrolyte to flow back to the receiving cavity, increasing the flow rate of the electrolyte, reducing the possibility of electrolyte stagnation between the seal 240 and the electrode post 250, and preventing electrolyte accumulation.

[0124] In some embodiments, the spacing between adjacent first seal grooves 300 is equal along the circumference of the seal 240.

[0125] In one feasible implementation, the first sealing groove 300 includes a first sub-groove and a second sub-groove, which are centrally symmetrical about the center of the seal 240. Referring to FIG7, the center of the seal 240 refers to the geometric center of the seal 240. The centrally symmetrical design of the first and second sub-grooves provides structural balance, enabling the seal 240 to distribute pressure evenly when under stress.

[0126] Along the radial direction of the seal 240, passing through the center of the seal 240, the length p1 of the line connecting the bottom of the first sub-groove and the bottom of the second sub-groove is greater than the diameter a of the electrode post 250. Thus, a first gap is formed between the inner wall of the first seal groove 300 and the outer periphery of the electrode post 250. During the electrolyte injection process, the electrolyte flows to the first gap. Since the first gap is connected to the receiving cavity, after the electrolyte injection is completed, the electrolyte flows back into the receiving cavity of the battery under gravity, which helps to prevent electrochemical reactions between the electrode post 250 and the transition ring 220 through the electrolyte.

[0127] As one possible implementation, the portion of the pole 250 near the seal 240 has a pole groove; a first gap is formed between the inner wall of the pole groove and the seal 240.

[0128] The portion of the outer periphery of the pole post 250 without the pole post groove abuts against the inner periphery of the seal 240, and a first gap is formed between the portion of the outer periphery of the pole post 250 with the pole post groove and the inner periphery of the seal 240.

[0129] After the electrolyte injection is completed, the electrolyte (i.e., the electrolyte in the first gap) located between the inner wall of the post groove and the inner circumferential side of the seal 240 can flow back to the battery's accommodating cavity.

[0130] In one feasible implementation, the pole groove includes a first sub-pole groove and a second sub-pole groove, which are centrally symmetrical about the center of the seal 240. The centrally symmetrical design of the first and second sub-pole grooves provides structural balance, enabling the pole 250 to distribute pressure evenly when under stress.

[0131] Along the radial direction of the seal 240, passing through the center of the seal 240, the length of the line connecting the bottom of the first sub-terminal groove and the bottom of the second sub-terminal groove is less than the inner diameter of the seal 240. This creates a first gap between the inner wall of the terminal groove and the inner circumference of the seal 240. During the electrolyte injection process, the electrolyte flows into the first gap. Since the first gap is connected to the receiving cavity, after the electrolyte injection is completed, the electrolyte flows back into the receiving cavity of the battery under gravity, helping to prevent electrochemical reactions between the terminal 250 and the transition ring 220 through the electrolyte.

[0132] As one feasible implementation, a second sealing groove 310 is provided on the side of the seal 240 near the transition ring 220, and a second gap is formed between the inner wall of the second sealing groove 310 and the transition ring 220.

[0133] For example, the portion of the outer peripheral side of the seal 240 where the second sealing groove 310 is not formed abuts against the inner peripheral side of the transition ring 220, and a second gap is formed between the portion of the outer peripheral side of the seal 240 where the second sealing groove 310 is formed and the inner peripheral side of the transition ring 220.

[0134] After the electrolyte injection is completed, the electrolyte (i.e., the electrolyte in the second gap) located between the inner wall of the groove 310 of the second sealing element and the inner circumferential side of the transition ring 220 can flow back to the battery's receiving cavity.

[0135] For example, there are multiple second sealing grooves 310. Along the circumference of the seal 240, multiple second sealing grooves 310 are spaced apart on the outer peripheral side of the seal 240. In this way, multiple second gaps are formed between the inner walls of the multiple second sealing grooves 310 and the electrode post 250. The arrangement of multiple second gaps provides multiple loop paths for the electrolyte to flow back to the receiving cavity, increasing the flow rate of the electrolyte, reducing the possibility of electrolyte stagnation between the seal 240 and the electrode post 250, and preventing electrolyte accumulation.

[0136] In some embodiments, the spacing between adjacent second seal grooves 310 is equal along the circumference of the seal 240.

[0137] In one feasible implementation, the second sealing groove 310 includes a third sub-groove and a fourth sub-groove, which are centrally symmetrical about the center of the seal 240. This centrally symmetrical design of the third and fourth sub-grooves provides structural balance, allowing the seal 240 to distribute pressure evenly under stress.

[0138] Along the radial direction of the seal 240, passing through the center of the seal 240, the length p2 of the line connecting the bottom of the third sub-groove and the bottom of the fourth sub-groove is less than the inner diameter b of the transition ring 220. Thus, a second gap is formed between the inner wall of the second seal groove 310 and the outer periphery of the electrode post 250. During the electrolyte injection process, the electrolyte flows to the second gap. Since the second gap is connected to the receiving cavity, after the electrolyte injection is completed, the electrolyte flows back into the battery's receiving cavity under gravity, helping to prevent electrochemical reactions between the electrode post 250 and the transition ring 220 through the electrolyte.

[0139] As one possible implementation, the portion of the transition ring 220 near the seal 240 has a connecting groove; a second gap is formed between the inner wall of the connecting groove and the seal 240.

[0140] For example, the portion of the inner circumferential side of the transition ring 220 without the connecting groove abuts against the outer circumferential side of the seal 240, and a second gap is formed between the portion of the inner circumferential side of the transition ring 220 with the connecting groove and the outer circumferential side of the seal 240.

[0141] After the electrolyte injection is completed, the electrolyte located between the inner wall of the connecting groove and the outer periphery of the seal 240 (i.e., the electrolyte in the second gap) can flow back to the battery's receiving cavity.

[0142] In one feasible implementation, the connecting groove includes a first sub-connecting groove and a second sub-connecting groove, which are centrally symmetrical about the center of the transition ring 220. The centrally symmetrical design of the first and second sub-connecting grooves provides structural balance, enabling the transition ring 220 to distribute pressure evenly when under stress.

[0143] Along the radial direction of the transition ring 220, passing through the center of the transition ring 220, the length of the line connecting the bottom of the first sub-connecting groove and the bottom of the second sub-connecting groove is greater than the outer diameter of the seal 240. This creates a second gap between the inner wall of the connecting groove and the outer periphery of the seal 240. During the electrolyte injection process, the electrolyte flows into the second gap. Since the second gap is connected to the receiving cavity, after the electrolyte injection is completed, the electrolyte flows back into the battery's receiving cavity under gravity, helping to prevent electrochemical reactions between the electrode post 250 and the transition ring 220 through the electrolyte.

[0144] Finally, it should be noted that other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This disclosure is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and alterations may be made without departing from its scope. The scope of this disclosure is limited only by the appended claims.

Claims

1. A cover plate assembly for a battery, characterized in that, The cover plate assembly includes: Cover plate (200) with through holes; A pole post (250), a portion of which is provided through the through hole; A spacer ring (210) surrounds the outer periphery of the pole post (250); An insulating ring (230) surrounds the outer periphery of the pole post (250) and is spaced apart from the spacer ring (210) along the extending direction of the pole post (250); A sealing element (240) surrounds the outer periphery of the pole post (250); along the extending direction of the pole post (250), the two sides of the sealing element (240) respectively seal against the spacer ring (210) and the insulating ring (230); A transition ring (220) surrounds the side of the seal (240) away from the pole post (250) and is located between the spacer (210) and the insulating ring (230); There is a first gap between the seal (240) and the pole (250) and / or a second gap is formed between the seal (240) and the transition ring (220).

2. The cover plate assembly according to claim 1, characterized in that, The transition ring (220) is connected to the cover plate (200).

3. The cover plate assembly according to claim 1, characterized in that, When there is a first gap between the seal (240) and the pole (250), the seal (240) is annular, and the first gap is formed between the inner circumferential side of the seal (240) and the outer circumferential side of the pole (250).

4. The cover plate assembly according to claim 3, characterized in that, The inner diameter n of the seal (240) is greater than the diameter a of the pole (250).

5. The cover plate assembly according to claim 3, characterized in that, When a second gap is formed between the seal (240) and the transition ring (220), the second gap is formed between the inner circumferential side of the transition ring (220) and the outer circumferential side of the seal (240).

6. The cover plate assembly according to claim 5, characterized in that, The outer diameter m of the seal (240) is smaller than the inner diameter b of the transition ring (220).

7. The cover plate assembly according to claim 5, characterized in that, Along the thickness direction of the cover plate (200), the sealing element (240) is interference-fitted with the spacer (210) and the insulating ring (230).

8. The cover plate assembly according to any one of claims 3-7, characterized in that, The sealing element (240) has a first sealing element groove (300) on the side near the pole post (250), and the first gap is formed between the inner wall of the first sealing element groove (300) and the pole post (250).

9. The cover plate assembly according to any one of claims 5-7, characterized in that, The portion of the pole (250) near the seal (240) has a pole groove; the first gap is formed between the inner wall of the pole groove and the seal (240).

10. The cover plate assembly according to claim 8, characterized in that, The first sealing groove (300) includes a first sub-groove and a second sub-groove, the first sub-groove and the second sub-groove being centrally symmetrical about the center of the sealing element (240); Along the radial direction of the seal (240), passing through the center of the seal (240), the length p1 of the line connecting the bottom of the first sub-groove and the bottom of the second sub-groove is greater than the diameter a of the pole post (250).

11. The cover plate assembly according to claim 9, characterized in that, The pole post groove includes a first sub-pole post groove and a second sub-pole post groove, and the first sub-pole post groove and the second sub-pole post groove are centrally symmetrical about the center of the seal (240); Along the radial direction of the seal (240), passing through the center of the seal (240), the length of the line connecting the bottom of the first sub-pole groove and the bottom of the second sub-pole groove is less than the inner diameter of the seal (240).

12. The cover plate assembly according to any one of claims 5-7, characterized in that, The seal (240) has a second seal groove (310) on the side near the transition ring (220), and the second gap is formed between the inner wall of the second seal groove (310) and the transition ring (220).

13. The cover plate assembly according to any one of claims 5-7, characterized in that, The transition ring (220) has a connecting groove on the side near the seal (240); the second gap is formed between the inner wall of the connecting groove and the seal (240).

14. The cover plate assembly according to claim 12, characterized in that, The second sealing groove (310) includes a third sub-groove and a fourth sub-groove, the third sub-groove and the fourth sub-groove being centrally symmetrical about the center of the sealing element (240); Along the radial direction of the seal (240), passing through the center of the seal (240), the length p2 of the line connecting the bottom of the third sub-groove and the bottom of the fourth sub-groove is less than the inner diameter b of the transition ring (220).

15. The cover plate assembly according to claim 13, characterized in that, The connecting groove includes a first sub-connecting groove and a second sub-connecting groove, the first sub-connecting groove and the second sub-connecting groove being centrally symmetrical about the center of the transition ring (220); Along the radial direction of the transition ring (220), passing through the center of the transition ring (220), the length of the line connecting the bottom of the first sub-connecting groove and the bottom of the second sub-connecting groove is greater than the outer diameter of the seal (240).

16. A battery casing, characterized in that, Includes a housing (100) and a cover assembly according to any one of claims 1-15; The housing (100) has an accommodating cavity with an opening at one end, and the cover assembly covers the opening.

17. The battery casing according to claim 16, characterized in that, The first gap and / or the second gap of the cover plate assembly are in communication with the receiving cavity.

18. A battery, characterized in that, It includes a battery cell and a battery housing as described in claim 16 or 17, wherein the battery cell is located in a receiving cavity of the battery housing.

19. An electrical appliance, characterized in that, Includes the battery as described in claim 18.

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