Jig suitable for arc-shaped battery pressurization formation and formation device for arc-shaped battery

Abstract

The utility model relates to arc battery field discloses a jig suitable for arc battery pressurization formation and is used to arc battery's formation device. When carrying out formation, the operator places arc battery 3 on the arc boss 11 of bottom plate 1, and the inner arc surface of arc battery 3 is naturally attached with arc boss 11. Subsequently, drive upper pressing plate 2 to press down, and its arc recess 21 is completely attached with the outer arc surface of arc battery 3, and uniform pressure is applied from above. The sandwich type structure of "arc boss 11-arc battery 3-arc recess 21" ensures that the pressure can be evenly distributed on the arc surface of the entire arc battery 3. The scheme solves the performance defects of arc battery 3 caused by uneven pressure during formation. Uniform pressure ensures that the electrolyte can fully and uniformly soak the pole piece, and promotes the formation of a dense and stable SEI film, thereby significantly improving the first efficiency, cycle life and consistency of arc battery 3.

Description

Technical Field

[0001] This utility model relates to the field of battery manufacturing, and in particular to a formation apparatus for arc-shaped batteries. Background Technology

[0002] With the explosive growth of the market for miniaturized and irregularly shaped wearable electronic products such as smart rings and smart bracelets, higher demands have been placed on the shape and performance of their internal energy storage components. Traditional square or cylindrical batteries cannot effectively utilize the unique annular or curved spaces within these products, severely restricting miniaturization design and capacity increases. Therefore, curved lithium-ion batteries, which fit closely to the product structure and maximize internal space utilization, have emerged and demonstrate enormous market potential.

[0003] However, the development of curved batteries is relatively recent, and the technological accumulation is relatively weak. Compared with the mature technology of square pouch batteries, curved batteries face many severe challenges in manufacturing processes, especially in the formation process, which is a core step that determines the overall performance of the battery.

[0004] Formation is the process by which a battery is activated and a stable SEI film is formed during its first charge. Its quality directly determines the battery's lifespan, safety, and consistency. During the research of this invention, the inventors discovered that existing formation processes and fixtures have fundamental defects for curved batteries: Currently used traditional planar pressure fixtures, or simple arc-shaped groove fixtures with mismatched curvature, cannot achieve uniform pressure application because their pressure surfaces cannot fully and evenly conform to the entire curved surface of the arc-shaped battery. This results in severely uneven pressure distribution across the battery's curved surface, with some areas experiencing insufficient pressure. Insufficient pressure significantly affects the electrolyte wetting effect and the formation quality and uniformity of the SEI film, easily leading to increased internal resistance, shortened cycle life, accelerated gas production, and even safety hazards. This is the primary bottleneck restricting the performance improvement and yield control of arc-shaped batteries.

[0005] Secondly, during the pressurized formation process, gases are generated inside the battery. These gases are collected in air pockets specifically left during the aluminum-plastic film encapsulation. Existing fixtures generally lack specialized optimized designs for these air pockets. The presence of these air pockets can lead to accidental compression and damage, or they can push up the pressure plate due to their space occupation, further disrupting the already uneven pressure distribution within the battery body and exacerbating the negative impacts of the aforementioned problems. Summary of the Invention

[0006] One of the objectives of this utility model is to provide a fixture suitable for the pressurization formation of arc-shaped batteries and a formation apparatus for arc-shaped batteries, which solves the problem of uniformity in pressurization of arc-shaped batteries.

[0007] In the first aspect, this embodiment provides a fixture suitable for the pressurized formation of arc-shaped batteries, including a base plate (1) and an upper pressure plate (2). The upper surface of the base plate (1) is provided with at least one upwardly protruding arc-shaped boss (11), the curvature of which is configured to match the inner arc surface of the arc-shaped battery (3). The lower surface of the upper pressure plate (2) is provided with an arc-shaped groove (21) that is recessed downwards corresponding to the position of the arc-shaped boss (11). The arc of the arc-shaped groove (21) is configured to match the outer arc surface of the arc-shaped battery (3).

[0008] Optionally, a clearance recess (12) is provided on the side of each of the arc-shaped protrusions (11), the top surface of the clearance recess (12) being lower than the top surface of the arc-shaped protrusion (11) for accommodating the air bag (31) of the arc-shaped battery (3).

[0009] Optionally, the upper pressure plate (2) is connected to a lifting device (45) for driving it to rise and fall relative to the base plate (1).

[0010] Optionally, a plurality of arc-shaped protrusions (11) and corresponding clearance recesses (12) are arranged in parallel on the base plate (1) to form at least one row of workstations for placing multiple arc-shaped batteries (3) at the same time.

[0011] Optionally, the upper pressure plate (2) is a long strip structure, and its lower surface is provided with an arc-shaped groove (21) that matches each arc-shaped protrusion (11) on the bottom plate (1).

[0012] Optionally, the base plate (1) is provided with two or more rows of parallel workstations.

[0013] Optionally, the upper pressure plate (2) is an integral plate with an arc-shaped groove (21) on its lower surface that matches all the arc-shaped protrusions (11) on the bottom plate (1).

[0014] Optionally, the upper pressure plate (2) includes multiple independent pressure plates, each of which corresponds to a row of workstations on the base plate (1).

[0015] Optionally, the upper pressure plate (2) is further provided with a downward recessed avoidance recess (22) on the side of the arc-shaped groove (21). When the upper pressure plate (2) is pressed down, each of the clearance recesses (22) is vertically opposite to each of the clearance recesses (12) on the bottom plate (1).

[0016] Secondly, the present invention provides a formation apparatus for arc-shaped batteries, comprising a frame (42), a control system, and a pressurized formation fixture disposed on the frame (42). The pressurized formation fixture is any of the above-described fixtures applicable to the pressurized formation of arc-shaped batteries; The formation apparatus further includes an electrode clamping part (43), which is disposed at the end of the arc-shaped boss (11) and is configured to clamp the tab (32) of the arc-shaped battery (3) when the arc-shaped battery (3) is placed on the arc-shaped boss (11) so as to electrically connect to an external formation power source.

[0017] As can be seen from the above, when performing formation using the scheme of this embodiment, the operator places the arc-shaped battery 3 on the arc-shaped protrusion 11 of the base plate 1, and the inner arc surface of the arc-shaped battery 3 naturally fits into the arc-shaped protrusion 11. Subsequently, the upper pressure plate 2 is driven to press down, and its upper arc-shaped groove 21 then completely fits into the outer arc surface of the arc-shaped battery 3, applying uniform pressure from above. This sandwich structure of "arc-shaped protrusion 11-arc-shaped battery 3-arc-shaped groove 21" ensures that the pressure can be evenly distributed across the entire arc-shaped curved surface of the arc-shaped battery 3.

[0018] This solution addresses the performance defects of the arc-shaped battery 3 caused by uneven pressure during formation. Uniform pressure ensures that the electrolyte can fully and evenly wet the electrodes and promotes the formation of a dense and stable SEI film, thereby significantly improving the initial efficiency, cycle life, and consistency of the arc-shaped battery 3. Attached Figure Description

[0019] The accompanying drawings, which are provided to further illustrate the present invention and form part of this application, do not constitute an undue limitation of the present invention.

[0020] Figures 1-3 This is a schematic diagram illustrating the working principle of a fixture suitable for pressurized formation of arc-shaped batteries provided in an embodiment of the present invention. Figure 4 A schematic diagram illustrating the corresponding principle of the electrode clamping device for the jig and formation equipment suitable for pressurized formation of arc-shaped batteries provided in this embodiment of the utility model; Figure 5 A schematic diagram illustrating the working principle of an automated lifting fixture suitable for the pressurization formation of arc-shaped batteries, provided in an embodiment of this utility model.

[0021] Figure label: 1: Base plate; 11: Arc-shaped boss; 12: Recessed area to avoid; 2: Upper pressure plate; 21: Arc-shaped groove; 22: Avoidance recess; 3: Arc-shaped battery; 31: Air bag; 32: Electrode tab; 41: Guide column; 42: Frame; 43: Electrode clamping part; 44: Base; 45: Lifting device Detailed Implementation

[0022] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. The illustrative embodiments and descriptions of the present invention are used to explain the present invention, but are not intended to limit the present invention.

[0023] Examples of embodiments of the present invention are shown in the accompanying drawings in a detailed description below, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout.

[0024] The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention. In the description of the present invention, it should be understood that terms such as "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the drawings and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the present invention.

[0025] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0026] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0027] See Figures 1-5 .

[0028] This utility model provides a fixture suitable for pressurized formation of arc-shaped batteries 3, the core of which lies in the unique structural design of the base plate 1 and the upper pressure plate 2.

[0029] The fixture includes a base plate 1 and an upper pressure plate 2. The upper surface of the base plate 1 is machined with at least one upwardly protruding arc-shaped boss 11. The curvature of the arc-shaped boss 11 is precisely calculated and machined to ensure that it highly matches the curvature of the inner arc surface of the arc-shaped battery 3. The lower surface of the upper pressure plate 2 is provided with downwardly recessed arc-shaped grooves 21 that correspond one-to-one with the positions of the arc-shaped bosses 11. The curvature of the arc-shaped grooves 21 is also designed to highly match the curvature of the outer arc surface of the arc-shaped battery 3.

[0030] The upper pressure plate 2 is positioned directly above the base plate 1, and the two move relative to each other via an external lifting device 45. In the non-working state, the upper pressure plate 2 is separated from the base plate 1; in the working state, the upper pressure plate 2 is pressed down, so that its arc-shaped groove 21 and the arc-shaped protrusion 11 of the base plate 1 together form a pressurized space that precisely matches the shape of the arc-shaped battery 3.

[0031] During formation, the operator places the arc-shaped battery 3 onto the arc-shaped protrusion 11 of the base plate 1, with the inner arc surface of the arc-shaped battery 3 naturally fitting against the arc-shaped protrusion 11. Then, the upper pressure plate 2 is driven down, causing its arc-shaped groove 21 to completely fit against the outer arc surface of the arc-shaped battery 3, applying uniform pressure from above. This sandwich structure of "arc-shaped protrusion 11 - arc-shaped battery 3 - arc-shaped groove 21" ensures that the pressure is evenly distributed across the entire arc-shaped surface of the arc-shaped battery 3.

[0032] This solution addresses the performance defects of the arc-shaped battery 3 caused by uneven pressure during formation. Uniform pressure ensures that the electrolyte can fully and evenly wet the electrodes and promotes the formation of a dense and stable SEI film, thereby significantly improving the initial efficiency, cycle life, and consistency of the arc-shaped battery 3.

[0033] It should be noted that the number of arc-shaped bosses 11 and arc-shaped grooves 21 can be set to one or more according to production cycle requirements. Their radius of curvature can be customized according to different models of arc-shaped batteries 3.

[0034] As an illustration of this embodiment, based on the above basic structure, in order to further optimize the production process and protect the arc-shaped battery 3, on the base plate 1, on the side of each arc-shaped protrusion 11 (usually on the same side from which the tab 32 is extended), there is a region whose top surface height is significantly lower than the top surface of the arc-shaped protrusion 11, namely, the avoidance recess 12. This avoidance recess 12 is adjacent to the arc-shaped protrusion 11, forming a continuous surface with a height difference.

[0035] In this way, when the operator places the arc-shaped battery 3, not only is the main body of the arc-shaped battery 3 placed on the arc-shaped protrusion 11, but the aluminum-plastic film air bag 31 of the arc-shaped battery 3 is also naturally placed in the relief recess 12. Thus, when the upper pressure plate 2 presses down, the pressure is entirely applied to the main body of the arc-shaped battery 3, while the air bag 31 is properly placed in the relief recess 12 and is not squeezed.

[0036] This design effectively avoids the risk of the air bag 31 rupturing due to pressure, and at the same time prevents the air bag 31 from lifting the upper pressure plate 2 and thus disrupting the pressure uniformity of the main body of the arc-shaped battery 3, further ensuring the stability of the formation quality.

[0037] The specific shape and size of the clearance recess 12 can be adjusted according to the size of the air bag 31, for example, it can be a square recess or a long groove.

[0038] To achieve large-scale and efficient production, this embodiment further provides a multi-station and automated drive solution.

[0039] Referring to the figure, the base plate 1 can be designed as a long strip, with multiple identical "arc-shaped bosses 11 + avoidance recesses 12" units arranged in parallel on its upper surface, forming at least one row of workstations. Correspondingly, the upper pressure plate 2 is also made as a long strip, with arc-shaped grooves 21 machined on its lower surface corresponding to each arc-shaped boss 11 on the base plate 1.

[0040] The base plate 1 is mounted on the base 44, and the upper pressure plate 2 is connected to the frame 42 via at least two parallel guide columns 41 and is driven by a lifting device 45. The lifting device 45 is preferably a cylinder or a servo motor to ensure a smooth pressing process and controllable pressure.

[0041] In this way, the operator or robot places multiple arc-shaped batteries 3 sequentially on each station of the base plate 1. After the equipment is started, a single upper pressure plate 2 can simultaneously apply uniform pressure to all arc-shaped batteries 3 in one stroke, completing the pressurization and formation of the entire row of arc-shaped batteries 3 in one go.

[0042] This solution significantly improves production efficiency and is suitable for the mass production of curved batteries. Servo motors or cylinder drives ensure precise and consistent pressure control.

[0043] For larger production lines, the base plate 1 can be set with two or more rows of workstations. In this case, the upper pressure plate 2 can be a single integral plate covering all workstations, or it can be composed of multiple independent pressure plates. The pressure plates can be controlled independently, providing greater flexibility.

[0044] As an illustration of this embodiment, an upwardly recessed clearance recess 22 can also be further machined on the lower surface of the upper pressure plate 2, on the side of each downwardly recessed arc-shaped groove 21. The depth of this clearance recess 22 is usually shallower than the arc-shaped groove 21, but its bottom height is lower than the arc apex height of the arc-shaped groove 21. The position of this clearance recess 22 is precisely designed so that when the upper pressure plate 2 and the bottom plate 1 are molded together, each clearance recess 22 on the upper pressure plate 2 is vertically aligned with the corresponding clearance recess 12 on the bottom plate 1.

[0045] Thus, during mold closing and pressurization, the air bag 31 of the arc-shaped battery 3 is not only accommodated within the clearance recess 12 of the base plate 1, but its upper space is also cleared by the clearance recess 22 of the upper pressure plate 2. Together, they form a complete and taller accommodating chamber in the vertical direction, completely enclosing the air bag 31.

[0046] This design provides more ample three-dimensional space for the air bag 31, eliminating the possibility of the upper pressure plate 2 contacting or squeezing the air bag 31 under any circumstances, thus providing the highest level of protection. At the same time, it ensures that all the pressure from the upper pressure plate 2 can be applied completely and without interference to the curved battery body 3.

[0047] The cross-sectional shape of the aforementioned clearance recess 22 can be rectangular, trapezoidal, or arc-shaped, as long as it can cooperate with the clearance recess 12 of the base plate 1 to form an effective space.

[0048] This embodiment further integrates the optimized fixture described above onto the formation apparatus to form a novel formation apparatus.

[0049] The formation apparatus includes a frame 42, a control system, the aforementioned pressure formation fixture, and an electrode clamping part 43. The base plate 1 of the fixture is fixedly mounted on the frame 42, and the upper pressure plate 2 is connected to the lifting device 45. The electrode clamping part 43 is fixedly mounted on the frame 42 and located on the side of the end of the arc-shaped boss 11 on the base plate 1, ensuring reliable clamping of the tabs 32 of the arc-shaped battery 3.

[0050] The electrode clamping part 43 can be in various forms, such as spring clamp, pneumatic clamp, or hydraulic clamp. The entire device can be integrated with a heating system to achieve integrated pressurization and heating.

[0051] In application, the arc-shaped battery 3 is placed on the base plate 1 of the fixture, and its tabs 32 are clamped by the electrode clamping part 43, thereby forming a circuit with the external formation power supply. The control system synchronously controls the lifting device 45 to press down the upper pressure plate 2, applying a preset pressure to the arc-shaped battery 3, and controls the formation power supply to charge and activate the arc-shaped battery 3 according to a preset program.

[0052] As can be seen from the above, the formation device of this utility model seamlessly integrates the optimized pressurization fixture with the formation process, with a high degree of automation, ensuring the consistency of process parameters, and providing a complete solution for the large-scale, high-performance manufacturing of arc-shaped batteries 3.

[0053] Based on the above-mentioned fixture and apparatus, an optimized fabrication process for the arc-shaped battery 3 includes the following steps: Stacking: Multiple positive and negative electrode sheets are stacked alternately through a stacking process, wherein the outermost electrode sheet is coated with active material on one side and the uncoated side faces outward.

[0054] Hot pressing: The stacked cores are placed into an arc-shaped hot pressing mold and shaped into the desired arc shape by heating and pressing.

[0055] Packaging: The arc-shaped stacked core is placed into a pre-stamped arc-shaped aluminum-plastic film shell, and top and side seals are performed, leaving the air bag 31 and the tab 32 exposed.

[0056] Electrolyte injection and pre-sealing: Inject electrolyte and pre-seal.

[0057] Pressure formation: The above-mentioned arc-shaped battery 3 is placed in the pressure formation fixture or device of this utility model, the tab 32 is clamped, a predetermined pressure is applied and heat formation is performed.

[0058] Subsequent processing: After the formation is completed, standard subsequent processes such as degassing, secondary sealing, edge trimming, and volume separation are carried out.

[0059] As can be seen from the above, the design of "single-sided coating of the outermost electrode" combined with "arc-shaped stacked core" maximizes the use of the arc space and improves the energy density of the arc battery 3. The dedicated pressure formation process provided in this embodiment ensures the quality of the SEI film, fundamentally reduces the internal resistance of the arc battery 3, extends the cycle life, and improves safety and consistency.

[0060] Experimental results show that, compared with the arc-shaped battery 3 formed using a traditional planar fixture, the arc-shaped battery 3 produced using the fixture and formation device of this invention exhibits significant and consistent improvements in key performance indicators such as internal resistance, initial charge-discharge efficiency, cycle life retention, and voltage consistency. In particular, due to the uniform pressure, the gas production rate of the arc-shaped battery 3 is significantly reduced during the formation process, greatly improving product safety and yield.

[0061] In summary, the fixture and device of this utility model have solved the technical bottleneck of the formation and pressurization of the arc battery 3, making it possible to produce arc batteries 3 on a large scale with high yield, thus meeting the market demand for high-end wearable devices such as smart rings.

[0062] The above embodiments do not constitute a limitation on the scope of protection of this technical solution. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the above embodiments should be included within the scope of protection of this technical solution.

Claims

1. A fixture suitable for pressurized formation of arc-shaped batteries, characterized in that, It includes a base plate (1) and an upper pressure plate (2). The upper surface of the base plate (1) is provided with at least one upwardly protruding arc-shaped boss (11), the curvature of which is configured to match the inner arc surface of the arc-shaped battery (3). The lower surface of the upper pressure plate (2) is provided with an arc-shaped groove (21) that is recessed downwards corresponding to the position of the arc-shaped boss (11). The arc of the arc-shaped groove (21) is configured to match the outer arc surface of the arc-shaped battery (3).

2. The fixture for pressurized formation of arc-shaped batteries according to claim 1, characterized in that, A clearance recess (12) is provided on the side of each of the arc-shaped protrusions (11), the top surface of the clearance recess (12) being lower than the top surface of the arc-shaped protrusion (11) for accommodating the air bag (31) of the arc-shaped battery (3).

3. The fixture for pressurized formation of arc-shaped batteries according to claim 1 or 2, characterized in that, The upper pressure plate (2) is connected to a lifting device (45) for driving it to rise and fall relative to the base plate (1).

4. The fixture for pressurized formation of arc-shaped batteries according to claim 1 or 2, characterized in that, The base plate (1) is provided with a plurality of arc-shaped protrusions (11) and corresponding clearance recesses (12) on each arc-shaped protrusion (11), forming at least one row of workstations for placing multiple arc-shaped batteries (3) at the same time.

5. The fixture for pressurized formation of arc-shaped batteries according to claim 4, characterized in that, The upper pressure plate (2) is a long strip structure, and its lower surface is provided with arc-shaped grooves (21) that match each arc-shaped protrusion (11) on the bottom plate (1).

6. The fixture for pressurized formation of arc-shaped batteries according to claim 4, characterized in that, The base plate (1) is provided with two or more rows of parallel workstations.

7. The fixture for pressurized formation of arc-shaped batteries according to claim 6, characterized in that, The upper pressure plate (2) is an integral plate with an arc-shaped groove (21) on its lower surface that matches all the arc-shaped protrusions (11) on the bottom plate (1).

8. The fixture for pressurized formation of arc-shaped batteries according to claim 6, characterized in that, The upper pressure plate (2) includes multiple independent pressure plates, each of which corresponds to a row of workstations on the base plate (1).

9. The fixture for pressurized formation of arc-shaped batteries according to claim 2, characterized in that, The upper pressure plate (2) is also provided with a downward recessed avoidance recess (22) on the side of the arc-shaped groove (21). When the upper pressure plate (2) is pressed down, each of the clearance recesses (22) is vertically opposite to each of the clearance recesses (12) on the bottom plate (1).

10. A formation apparatus for arc-shaped batteries, comprising a frame (42), a control system, and a pressurized formation fixture disposed on the frame (42), characterized in that: The pressurized formation fixture is any one of the fixtures described in claims 1 to 9 that is suitable for pressurized formation of arc-shaped batteries; The formation apparatus further includes an electrode clamping part (43), which is disposed at the end of the arc-shaped boss (11) and is configured to clamp the tab (32) of the arc-shaped battery (3) when the arc-shaped battery (3) is placed on the arc-shaped boss (11) so as to electrically connect to an external formation power source.

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