Arc-shaped battery and electronic product

Abstract

The utility model relates to arc battery field discloses an arc battery and electronic product. Arc battery includes, electric core, aluminium plastic film, electric core is arc along length direction, forms the arc cavity with the shape of arc battery matching on aluminium plastic film, the bottom surface of arc cavity is arc along length direction, the two arc length edges of the opening of arc cavity are parallel with the bottom surface of arc cavity, the electric core is limited in arc cavity, the aluminium plastic film of extending in the first arc length edge outside the opening of arc cavity is folded along the first arc length edge, the aluminium plastic film of folding covers the opening of arc cavity completely, and is pasted with the aluminium plastic film of extending in the second arc length edge outside the opening of arc cavity, two width edges, forms heat sealing edge outside second arc length edge respectively in the two width edges of the opening of arc cavity, the surface heat fusion sealing combination of two aluminium plastic films in each heat sealing edge, the end of the lug of electric core is stretched out from the heat sealing edge of width end, the electrode is sealed with heat sealing edge, and the electric core is sealed in aluminium plastic film shell.

Description

Technical Field

[0001] This utility model relates to the field of battery manufacturing, and in particular to an arc-shaped battery and electronic product. Background Technology

[0002] As smart wearable products become more widely used, the demand for rechargeable batteries is also increasing. The requirements for battery shape and size are becoming more stringent. Summary of the Invention

[0003] One of the objectives of this utility model embodiment is to provide an arc-shaped battery and electronic product, wherein the arc-shaped battery using this technical solution has a compact structure and more reliable airtightness.

[0004] In a first aspect, this embodiment provides an arc-shaped battery, comprising a battery cell and an aluminum-plastic film, wherein the battery cell is arc-shaped. An arc-shaped cavity matching the arc shape of the battery cell is formed on the aluminum-plastic film. The arc-shaped cavity is arc-shaped along its length, and the battery cell is confined within the arc-shaped cavity. An aluminum-plastic film extending beyond the first arc-shaped length edge of the opening of the arc-shaped cavity is folded along the first arc-shaped length edge, completely covering the opening of the arc-shaped cavity. This folded aluminum-plastic film adheres to the aluminum-plastic film extending beyond the second arc-shaped length edge and both width edges of the opening of the arc-shaped cavity, forming heat-sealed edges at the two width edges and the second arc-shaped length edge of the opening of the arc-shaped cavity. At each of the heat-sealed edges, the surfaces of the two aluminum-plastic films that are in contact with each other are heat-sealed together to seal the opening of the arc-shaped cavity, forming an aluminum-plastic film shell. The end of the electrode of the battery cell extends from the heat-sealed edge at the wide end, and the electrode is sealed together with the heat-sealed edge, thus sealing the battery cell inside the aluminum-plastic film shell.

[0005] Optionally, the battery cell is a wound battery cell, which is hot-pressed into an arc shape, and the bending direction of the arc is perpendicular to the direction of the winding axis.

[0006] Optionally, the wound cell is formed by winding the stacked negative electrode sheet, separator, and positive electrode sheet, wherein the ends of the positive electrode sheet and the negative electrode sheet are respectively the positive electrode tab welding area and the negative electrode tab welding area exposed for the current collector. On the outer periphery of the wound battery cell, the positive electrode tab welding area and the negative electrode tab welding area are respectively exposed on the outer peripheral surface of the wound battery cell. The positive electrode tab and the negative electrode tab are respectively welded to the positive electrode tab welding area and the negative electrode tab welding area.

[0007] Optionally, the wound cell is formed by winding the negative electrode sheet, the separator, and the positive electrode sheet sequentially stacked from the inside to the outside. On the outer periphery of the wound cell, the end of the negative electrode sheet extends beyond the end of the positive electrode sheet and is wound around the outer periphery of the wound cell.

[0008] Optionally, the positive and negative tabs are opposite each other along the radial direction of the wound cell.

[0009] Optionally, the positive and negative electrodes are symmetrically distributed at 180 degrees.

[0010] Optionally, one tab of the battery cell extends from one width of the aluminum-plastic film shell, and the other tab extends from the other width of the aluminum-plastic film shell.

[0011] Optionally, the outer surface of the closed bottom of the arc-shaped cavity is concave, forming the inner arc of the arc-shaped battery, and the outer surface of the aluminum-plastic film covering the opening of the arc-shaped cavity is convex, forming the outer arc of the arc-shaped battery.

[0012] Optionally, the bottom surface of the arc-shaped cavity is parallel to the aluminum-plastic film covering the opening of the arc-shaped cavity.

[0013] Optionally, the heat-sealed edge located outside the second arc-shaped length edge of the opening of the arc-shaped cavity is folded along the second arc-shaped length edge toward the side of the arc-shaped cavity and attached to the outside of the side of the arc-shaped cavity.

[0014] Optionally, an adhesive layer is also bonded between the outer surface of the side of the arc-shaped cavity and the heat-sealed edge of its outer surface.

[0015] Optionally, the heat-sealing width of the heat-sealing edge located outside the second arc-shaped length edge of the opening of the arc-shaped cavity is less than or equal to the thickness of the arc-shaped battery. The length edge of the heat-sealed edge located outside the second arc-shaped length edge of the opening of the arc-shaped cavity does not exceed the intersection edge between the side wall of the arc-shaped cavity and the bottom surface of the arc-shaped cavity.

[0016] Optionally, the heat-sealing width of the heat-sealing edge located outside the second arc-shaped length edge is greater than the thickness of the arc-shaped battery, and less than or equal to the sum of the width and thickness of the arc-shaped battery. The portion of the heat-sealed edge located outside the second arc-shaped length edge, extending beyond the intersecting edge between the sidewall of the arc-shaped cavity and the bottom surface of the arc-shaped cavity, also flips along the intersecting edge toward the bottom surface of the arc-shaped cavity and adheres to the outside of the bottom surface.

[0017] Optionally, an adhesive layer is also bonded between the bottom surface of the arc-shaped cavity and the heat-sealed edge of its outer surface.

[0018] Optionally, the outer edge of the heat-sealed edge, which is bonded to the outside of the arc-shaped cavity by the adhesive layer, is the cut end face. A waterproof adhesive layer is applied to the cut end face.

[0019] Optionally, the waterproof adhesive layer extends at least 2 mm beyond the cut end face at each point.

[0020] Secondly, this utility model provides an electronic product, including, Any of the above-mentioned arc-shaped batteries, The driving circuit is electrically connected to the two electrodes of the arc-shaped battery.

[0021] As can be seen from the above, the arc-shaped battery of this embodiment is particularly suitable for use in arc-shaped or ring-shaped electronic products (such as ring-shaped electronic products). Compared with the prior art, which has aluminum-plastic film heat-sealing edges around the perimeter, the arc-shaped battery of this embodiment has a completely sealed integral structure on one arc-shaped side without heat sealing, which better ensures airtightness. Moreover, the absence of heat-sealing edges on this side reduces the space occupied by heat-sealing edges in the arc-shaped battery, which is conducive to fully maximizing the utilization space of the battery cell. Attached Figure Description

[0022] 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.

[0023] Figure 1 , 2 This is a three-dimensional structural diagram of an arc-shaped battery provided in Embodiments 1 and 2 of this utility model; Figure 3 , 4 This is a three-dimensional structural schematic diagram of another arc-shaped battery provided in Embodiments 1 and 2 of this utility model; Figure 5 , 6 This is a three-dimensional structural diagram of an arc-shaped battery provided in Embodiments 1 and 2 of this utility model; Figure 7 , 8 This is a three-dimensional structural schematic diagram of another arc-shaped battery provided in Embodiments 1 and 2 of this utility model; Figure 9 This is a schematic diagram of a negative electrode structure provided in Embodiment 2 of this utility model; Figure 10 This is a schematic diagram of a positive electrode structure provided in Embodiment 2 of the present invention; Figure 11 This is a schematic diagram of a wound battery cell with unwelded tabs provided in Embodiment 2 of this utility model.

[0024] Figure 12This is a schematic diagram of the structure of a wound battery cell after welding tabs, as provided in Embodiment 2 of this utility model.

[0025] Figure label: 1: Electrode; 2: Arc-shaped cavity; 3: Negative electrode sheet; 31: Negative electrode tab welding area; 32: Negative electrode tab; 4: Positive electrode sheet; 41: Positive electrode tab welding area; 42: Positive electrode tab; 43: Single-sided coating section; 5: Winded battery cells. Detailed Implementation

[0026] 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.

[0027] 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.

[0028] 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.

[0029] Furthermore, the terms "" 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 with "" 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.

[0030] 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.

[0031] Example 1: Stacked wound battery.

[0032] See Figure 1-8 .

[0033] This embodiment provides an arc-shaped battery, which is arc-shaped along its length and is particularly suitable for use as a power supply battery for ring-shaped or arc-shaped electronic products such as rings or bracelets.

[0034] The arc-shaped battery includes stacked cells (not shown in the figure) and an aluminum-plastic film for encapsulating the stacked cells.

[0035] A laminated battery cell consists of a sheet-like positive electrode, a separator layer, and a negative electrode, all stacked together. After stacking, the middle of the laminated battery cell along its length is initially fixed to prevent it from spreading out. In its natural state, the laminated battery cell is placed in a support mold of different shapes. Under the action of gravity, the electrodes and separator layer of the laminated battery cell adhere tightly to the top surface of the support mold, and the laminated battery cell takes on a shape consistent with the current support mold.

[0036] For example, when the top surface of the support mold is a raised arc along the length direction, the two wide ends of the stacked battery cell placed on it naturally droop under the action of gravity. The stacked battery cell on the support mold is naturally arc-shaped along the length direction, with the middle part of the arc raised and the two ends drooping. The inner arc of the side of the stacked battery cell is close to the support mold, and the outer arc is located on the top surface of the arc-shaped battery.

[0037] When the supporting mold is a concave arc shape along the length direction, the stacked cells on it are arc shapes that can only be concave in the middle and rise at both ends. The outer arc of the side of the stacked cells is in close contact with the supporting mold, and the inner arc is located on the top surface of the arc-shaped battery.

[0038] The tab 1 of the laminated cell extends from its wide end. This embodiment provides a suitable curved battery for extremely narrow applications, for example, the curved battery has a width of approximately 4 mm and a thickness of approximately 2 mm. The positive tab of the laminated cell extends from one wide end of the laminated cell, and the negative tab extends from the other wide end of the laminated cell. Adhesive films are attached to both sides of the positive and negative tabs near the root of the laminated cell, so that during heat sealing, the adhesive films on both surfaces of the tab 1 are heat-fused to the adhesive on the surfaces of the aluminum-plastic film on both sides to seal them together, thus achieving a seal between the tab 1 and the aluminum-plastic film on both sides. The exposed metal end of the tab 1 extends from both wide ends of the curved battery.

[0039] An arc-shaped cavity 2 matching the shape of the laminated battery cell is pre-stamped on an aluminum-plastic film. The inner surface of the bottom of the arc-shaped cavity 2 is a curved surface that is arc-shaped along the length direction. The arc-shaped cavity 2 is a support mold for the laminated battery cell. The shape of the inner surface of the bottom of the arc-shaped cavity 2 determines the shape of the laminated battery cell placed in the arc-shaped cavity 2.

[0040] In this embodiment, the two length edges of the opening of the arc-shaped cavity 2 are arcs parallel to its bottom surface, and the two width edges of the opening of the arc-shaped cavity 2 can be straight lines respectively.

[0041] For illustration, the thickness of the aluminum-plastic film used is approximately 0.076 mm.

[0042] As an illustration of this embodiment, the arc-shaped cavity 2 formed in the aluminum-plastic film can be symmetrical about, but not limited to, the line connecting the midpoints of the two length edges.

[0043] As an illustration of this embodiment, after the stacked battery cell is placed into the arc-shaped cavity 2 of the aluminum-plastic film and shaped into an arc shape in the length direction, the stacked battery cell can be further hot-pressed, but not limited to, to fix the arc shape of the stacked battery cell.

[0044] An integral aluminum-plastic film extends from each of the four sides of the opening of the arc-shaped cavity 2. The aluminum-plastic film extending beyond the two width edges and the first arc-shaped length edge of the opening of the arc-shaped cavity 2 extends by a certain width for heat sealing. The extension width of the aluminum-plastic film extending beyond the second arc-shaped length edge of the opening of the arc-shaped cavity 2 is the sum of the width of the arc-shaped cavity 2 and the heat-sealing width of the heat-sealing edge. After the stacked battery cell is inserted, the aluminum-plastic film is folded along the second arc-shaped length edge of the opening of the arc-shaped cavity 2, so that the folded aluminum-plastic film completely covers the opening of the arc-shaped cavity 2 and is in face-to-face contact with the aluminum-plastic film extending beyond the two width edges and the first arc-shaped length edge of the opening of the arc-shaped cavity 2.

[0045] Electrolyte filling and aluminum-plastic film encapsulation are performed. Specifically, aluminum-plastic film encapsulation involves using an aluminum-plastic film heat-sealing device to heat-seal two opposing aluminum-plastic film layers located at the two width ends of the opening of the arc-shaped cavity 2 and outside the second arc-shaped length edge. The surface of the heat-pressing head acting on the surface of the aluminum-plastic film is parallel to the bottom surface of the aluminum-plastic film, forming arc-shaped heat-sealing edges of a certain width at the two width ends of the opening of the arc-shaped cavity 2 and outside the second arc-shaped length edge. At each heat-sealing edge, the surface materials of the two adjacent aluminum-plastic film layers are heat-fused and sealed together. The adhesive tape on the tab 1 of the laminated battery cell is heat-fused and sealed together with the surface materials of the two adjacent aluminum-plastic film layers, sealing the tab section on the heat-sealing edge with the two aluminum-plastic film layers. The laminated battery cell is sealed inside the aluminum-plastic film shell, and the exposed metal end of the tab 1 extends from the heat-sealing edge for external connection.

[0046] As an illustration of this embodiment, the heat-sealing width of each heat-sealing edge may be, but is not limited to, approximately 1.0 mm.

[0047] As an illustration of this embodiment, electrolyte injection can be performed first, or it can be performed after heat sealing of any one or two sides of the aluminum-plastic film, in order to avoid electrolyte contamination of the surface of the aluminum-plastic film and affecting the heat sealing effect.

[0048] Electrolyte filling and aluminum-plastic film heat sealing processes can be, but are not limited to, those described in existing technologies.

[0049] As can be seen from the above, the arc-shaped battery of this embodiment is particularly suitable for arc-shaped or ring-shaped electronic products (such as ring-shaped or bracelet-shaped electronic products for wear by users). Compared with the prior art, which has aluminum-plastic film heat-sealing edges on both length edges, the arc-shaped battery of this embodiment is heat-sealed only on one arc-shaped length side, while the other arc-shaped length side is a completely sealed integral structure without heat sealing. The airtightness of the structure of this embodiment is better guaranteed, and the space occupied by the heat-sealing edge in the arc-shaped battery is reduced, which is conducive to fully improving the utilization space of the stacked cells.

[0050] In addition, in this embodiment, the two length edges of the arc-shaped cavity 2 opening of the arc-shaped battery are both arc-shaped length edges, and the heat-sealing area on the arc-shaped length side is an arc-shaped heat-sealing edge. The two arc-shaped curved surfaces of the battery are parallel, which can better adapt to the power supply position of ring or semi-ring electronic products and make full use of the power supply position space.

[0051] To further illustrate the solution of this embodiment, the following example uses the shape of the arc-shaped cavity 2 on the aluminum-plastic film as an example.

[0052] A stamping die is used to stamp the surface of the aluminum-plastic film to form an arc-shaped cavity 2.

[0053] For example, see Figures 1-4As shown, the inner surface of the closed bottom of the arc-shaped cavity 2 is arc-shaped along its length, with the middle part of the arc protruding towards the opening of the arc-shaped cavity 2. Correspondingly, the outer surface of the bottom of the arc-shaped cavity 2 (i.e., the outer surface of the arc-shaped battery at this location) is concave, and the two long edges of the opening of the arc-shaped cavity 2 are arc-shaped parallel to the bottom surface of the arc-shaped cavity 2, that is, the middle parts of the two long edges of the arc protrude upwards respectively. After inserting the stacked battery cells, the aluminum-plastic film is folded, the electrolyte is injected, and the aluminum-plastic film is heat-sealed to obtain the arc-shaped battery. On the arc-shaped battery, the aluminum-plastic film covering the opening of the arc-shaped cavity 2 has a convex curved surface, parallel to the bottom surface of the arc-shaped cavity 2. Viewed from the side, the bottom surface of the arc-shaped cavity 2 of the aluminum-plastic film is the inner arc of the arc-shaped battery, and the aluminum-plastic film covering the opening of the arc-shaped cavity 2 is the outer arc of the arc-shaped battery. The tab 1 is located at the two width ends of the outer arc. The outer arc and the inner arc are parallel, and the distance between the inner arc and the outer arc is the thickness of the battery.

[0054] For example, see Figures 5-8 As shown, the inner surface of the closed bottom of the arc-shaped cavity 2 formed on the aluminum-plastic film is arc-shaped along its length, with the middle part of the arc concave towards the bottom. Correspondingly, the outer surface of the bottom of the arc-shaped cavity 2 (i.e., the outer surface of the arc-shaped battery at this location) is convex, and the two long edges of the opening of the arc-shaped cavity 2 are arc-shaped parallel to the bottom surface of the arc-shaped cavity 2, that is, the middle parts of the two long edges of the arc are concave towards the bottom. After the stacked battery cells are placed, the aluminum-plastic film is folded, electrolyte is injected, and the aluminum-plastic film is heat-sealed to obtain the arc-shaped battery. On the arc-shaped battery, the aluminum-plastic film covering the opening of the arc-shaped cavity 2 is concave and parallel to the bottom surface of the arc-shaped cavity 2. Viewed from the side, the bottom surface of the arc-shaped cavity 2 of the aluminum-plastic film is the outer arc of the arc-shaped battery, and the aluminum-plastic film covering the opening of the arc-shaped cavity 2 is the inner arc of the arc-shaped battery. The tabs 1 are located at the two opposite ends of the inner arc. The outer arc and the inner arc are parallel, and the distance between the inner arc and the outer arc is the thickness of the battery.

[0055] As an illustration of this embodiment, the heat-sealed edges at the two wide ends of the arc-shaped battery can be non-folded to avoid bending of the tabs 1. The heat-sealed edges at the two wide ends extend in an arc shape at both ends of the aluminum-plastic film covering the opening of the arc-shaped cavity 2. As the outer edges of the two wide ends of the aluminum-plastic film encapsulating the opening of the arc-shaped cavity 2, the two tabs 1 extend out of the two wide ends of the arc-shaped battery.

[0056] As an illustration of this embodiment, the heat-sealing width of the heat-sealing edge extending beyond the second arc-shaped length edge of the opening of the arc-shaped cavity 2 can be widened, but is not limited to, making it greater than the heat-sealing width of the heat-sealing edges at both width ends, thereby improving the reliability of the heat-sealing seal of the arc-shaped battery. Preferably, but not limited to, the heat-sealing width of the heat-sealing edge located outside the second arc-shaped length edge of the opening of the arc-shaped cavity 2 is greater than the heat-sealing width of the heat-sealing edges at both width ends, and is equal to or slightly less than the thickness of the arc-shaped battery. For example, assuming the thickness of the arc-shaped battery (i.e., the height of the side surface of the arc-shaped cavity 2) is 2mm, and the heat-sealing width of the arc-shaped heat-sealing edge at both width ends is 1.0mm, then the heat-sealing width of the heat-sealing edge located outside the second arc-shaped length edge of the opening of the arc-shaped cavity 2 is greater than 1.0mm and less than or equal to 3mm, such as 1.5mm or 2mm. After heat sealing, the heat-sealed edge is folded along the second arc-shaped length edge of the opening of the arc-shaped cavity 2 towards the outer side of the arc-shaped cavity 2, so that the widened heat-sealed edge is tightly attached to the outer side of the arc-shaped cavity 2, and does not exceed the arc-shaped intersection edge between the side and bottom surfaces of the arc-shaped cavity 2, resulting in a compact arc-shaped battery structure. As an illustration of this embodiment, adhesive is also coated on the outer surface of the side of the arc-shaped cavity. The adhesive firmly bonds the heat-sealed edge folded onto the outer surface of the concave side to the side of the arc-shaped battery, preventing it from loosening and affecting the appearance consistency of the arc-shaped battery, improving the structural compactness of the aluminum-plastic film casing, reducing the space occupied by the aluminum-plastic film casing, and increasing the effective space of the stacked cells. Specifically, but not limited to, the method of heat-pressing the side of the arc-shaped battery can be used to cure the adhesive and tightly bond the heat-sealed edge to the side of the arc-shaped battery.

[0057] As an illustration of this embodiment, the width of the heat-sealing edge outside the second arc-shaped length edge of the opening of the arc-shaped cavity 2 can be further widened to further enhance the airtight reliability of the arc-shaped battery. It is possible, but not limited to, making the heat-sealing width of the heat-sealing edge outside the second arc-shaped length edge of the opening of the arc-shaped cavity 2 greater than the thickness of the arc-shaped battery and less than or equal to the sum of the width and thickness of the arc-shaped battery. For example, assuming the width of the arc-shaped battery is 4mm and the thickness is 1.5mm, and the heat-sealing width of the heat-sealing edge at both ends of the width is 1mm, then the heat-sealing width of the heat-sealing edge outside the second arc-shaped length of the opening of the arc-shaped cavity 2 is greater than 1.5mm and equal to or less than 5.5mm, for example, 2mm or 5.5mm. After heat sealing, the heat-sealed edge is folded once along the second arc-shaped length edge of the opening of the arc-shaped cavity 2 towards the outer side of the arc-shaped cavity 2, so that the heat-sealed edge is tightly attached to the outer surface of the side of the arc-shaped cavity 2. Then, the heat-sealed edge is further folded beyond the arc-shaped intersection edge between the side of the arc-shaped cavity 2 and the bottom surface of the arc-shaped cavity 2, so that it is tightly attached to the bottom surface of the arc-shaped cavity 2 and does not exceed the first arc-shaped length edge of the bottom surface of the arc-shaped cavity 2, resulting in a compact structure of the arc-shaped battery.

[0058] As an illustration of this embodiment, adhesive is also applied to the outer surface of the bottom surface of the arc-shaped cavity. The adhesive firmly bonds the heat-sealed edge, which is folded onto the outer surface of the bottom surface of the concave body, to the side of the arc-shaped battery, preventing it from loosening and affecting the appearance consistency of the arc-shaped battery. This also helps improve the compactness of the aluminum-plastic film casing, reduces the space occupied by the aluminum-plastic film casing, and increases the effective space of the stacked battery cells. Specifically, but not limited to, using a method of hot-pressing the bottom surface of the arc-shaped cavity of the arc-shaped battery to cure the adhesive and tightly bond the heat-sealed edge to the bottom surface of the arc-shaped cavity of the arc-shaped battery.

[0059] The arc-shaped battery of this embodiment can be applied to arc-shaped or ring-shaped electronic products. Any arc-shaped segment on the electronic product serves as a power supply compartment. Both ends of the power supply compartment are provided with power input terminals that are electrically connected (e.g., soldered) to the positive and negative terminals of the arc-shaped battery of this embodiment. The two power input terminals are electrically connected to the positive and negative terminals of the driving circuit of the electronic product. The arc-shaped battery supplies power to the driving circuit to drive the electronic product to work.

[0060] Example 2: Winded arc-shaped battery.

[0061] See Figures 1-12 As shown.

[0062] The difference from Example 1 is as follows: The battery cell inside the arc-shaped battery in this embodiment is a wound battery cell 5 made using a winding process.

[0063] The structure and winding process of the wound cell 5 are described in the existing technology.

[0064] Schematic, see Figure 9 As shown, one end of the negative electrode sheet 3 along its length has a double-sided uncoated area, which serves as the negative electrode tab welding area 31, where the negative electrode tab 32 is welded; see also Figure 10 As shown, one end of the positive electrode sheet 4 along its length is provided with a double-sided uncoated area, which serves as the positive electrode tab welding area 41, where the positive electrode tab 42 is welded. Furthermore, since the positive electrode is not covered by the negative electrode on the wound cell 5, a section of the positive electrode near the positive electrode tab welding area 41 is a single-sided coated section 43, and the outward-facing surface of the single-sided coated section 43 is not coated with active material.

[0065] During winding, the positive electrode 4, separator, and negative electrode 3 are stacked together, with the negative electrode 3 inside and the positive electrode 4 outside, as illustrated. The length of the negative electrode 3 is longer than that of the positive electrode 4. The winding proceeds from the inside out to form a wound cell 5. When winding reaches the negative electrode tab welding area 31 of the negative electrode 3, the end of the negative electrode 3 is fixed, ensuring that the negative electrode tab welding area 31 is tightly attached to the outside of the wound cell 5 in the same direction as the winding. The single-sided coated area of ​​the positive electrode 4 is then further wound, continuing for half a turn until the positive electrode tab welding area 41 of the positive electrode 4 is tightly attached to the outside of the wound cell 5 (before reaching the end of the negative electrode 3). The end of the positive electrode 4 is then fixed. At this point, the ends of the positive electrode tab welding area 41 and the negative electrode tab welding area 31 are respectively tightly attached to the two ends of the wound cell 5 in the radial or approximately radial direction, forming a relative positional relationship, thus obtaining... Figure 11 The wound cell 5 is shown. See also... Figure 12 As shown, positive electrode tab 42 and negative electrode tab 32 are welded respectively. Positive electrode tab 42 and negative electrode tab 32 extend from the two opposite ends of the winding body, and the direction of extension is the same as the winding direction of the winding cell 5. Positive electrode tab 42 and negative electrode tab 32 are arranged opposite each other along the radial direction of the winding cell, for example, but not limited to, they are symmetrically distributed at 180 degrees.

[0066] After obtaining the wound cell 5, the wound cell 5 is placed on an arc-shaped hot pressing platform and hot-pressed. Under the action of heat and pressure, the wound cell 5 is pressed tightly against the arc-shaped hot pressing platform to form an arc shape. The bending direction of the arc shape is perpendicular to the winding axis direction, thus obtaining an arc-shaped wound cell 5. The positive electrode tab 42 and the negative electrode tab 32 extend from the two ends of the arc-shaped battery respectively.

[0067] Subsequent processes such as cell insertion into the aluminum-plastic film casing, electrolyte injection, and sealing are the same as in Example 1. The shape of the resulting arc-shaped battery after aluminum-plastic film encapsulation is shown in [reference needed]. Figures 1-8 This will not be elaborated upon here.

[0068] The wound arc-shaped battery in this embodiment is similar to that in the previous embodiment and can be applied to electronic products such as smart rings and bracelets.

[0069] In summary, the technical solution of this embodiment has the following significant advantages: The pre-stamped arc-shaped cavity 2 precisely positions and limits the battery cell. During packaging, the aluminum-plastic film, with its arc-shaped edge as a single unit, seals the side, significantly reducing the heat-sealing edge and avoiding defects caused by misalignment, heat radiation burns to the cell, and electrolyte contamination of the seal edge—common in traditional arc-shaped battery packaging. This also helps reduce thermal and mechanical damage to the cell body during heat sealing, preventing electrode active material detachment and microstructural damage, thus lowering the battery's internal resistance and other defect rates. Furthermore, the integrated aluminum-plastic film seal structure with its arc-shaped edge makes the battery's arc structure more stable. The single-sided heat-sealing design reduces the space occupied by the heat-sealing edge, allowing for larger, higher-capacity cells within the same external dimensions, thus improving the product's volumetric energy density.

[0070] To demonstrate the aforementioned beneficial effects, the applicant conducted rigorous comparative experiments.

[0071] Comparative example: The curved battery is prepared using a traditional double-sided heat-sealing process. Specifically, the curved battery cell of this embodiment is placed inside an arc-shaped cavity 2 made of an aluminum-plastic film, and another aluminum-plastic film is used to cover the top. Then, the battery cell is heat-sealed around its perimeter (including the two long and two wide arc sides).

[0072] Under the same conditions, using the same specifications of cell material, aluminum-plastic film, and electrolyte, 1000 arc-shaped batteries with dimensions of 30mm * 4mm * 2mm (arc length * width * thickness) were produced using three different processes and then tested. The following experimental data comparison table was obtained: Production yield 85.2% 98.5% 98.2% Improved yield Heat sealing burn failure rate 7.5% 0.3% 0.5% Almost no burns Packaging leakage failure rate 5.1% 0.8% 0.9% Reliable sealing Average DC internal resistance (DCIR) 125 mΩ 108 mΩ 110 mΩ Internal resistance reduced Initial discharge capacity (0.2C) 29.5 mAh 30.2 mAh 30.0 mAh Capacity increase Capacity retention after 300 cycles 78.5% 89.2% 88.5% Lifespan extension .

[0073] As can be seen from the table, whether it is the stacked type in Example 1 or the wound type in Example 2, after adopting the single-sided folding packaging process of this utility model, the production yield, electrical performance and cycle life are consistent and significantly better than the traditional double-sided heat sealing process of the control example.

[0074] This invention greatly eliminates the problem of battery cell burns caused by close-range heat radiation from the sealing blade in existing technologies (reducing the failure rate from 7.5% to 0.3%~0.5%).

[0075] By adopting the technical solution of this embodiment, the battery internal resistance is significantly reduced (~13%), and the cycle life is greatly improved (capacity retention is improved by about 10%).

[0076] Example 3: Detailed explanation of the manufacturing process of arc-shaped batteries.

[0077] To more clearly illustrate the preparation method of this utility model, this section will describe in detail the key process steps, which can be applied to the battery production of any of the above embodiments.

[0078] 1. The folding and covering process of curved aluminum-plastic film specifically includes: Preheating and softening: A strip-shaped hot air gun that matches the shape of the curved edge is used to scan and heat the area of ​​the aluminum-plastic film to be folded. The temperature is controlled at about 80°C to 120°C, such as 100°C, to soften the aluminum-plastic film in this area, increase its ductility, and facilitate subsequent plastic deformation without springback.

[0079] Contour Folding: A pressure block is driven, the working surface of which is an arc surface that matches the curvature of the side wall of the arc-shaped cavity. The pressure block moves along a trajectory that matches the contour of the side wall of the first arc length edge of the arc-shaped cavity. For example, it first presses down vertically to contact the aluminum-plastic film, and then performs a "translation-covering" movement along the contour of the side wall of the arc-shaped cavity, as if "smoothing", smoothly folding the aluminum-plastic film and completely covering the opening of the arc-shaped cavity.

[0080] As an illustration of this embodiment, micropores are also provided on the working surface of the contour pressing block. During the movement, negative pressure is applied to firmly adsorb the aluminum-plastic film onto the surface of the pressing block, ensuring that the aluminum-plastic film and the curved surface of the pressing block are completely in contact during the folding process, without slippage or wrinkles.

[0081] The curved heat-sealing edge forming process is completed using a customized contour-following heat-sealing head: The working surfaces of the upper and lower molds of the contour heat sealing head are not flat planes, but matching curved surfaces precisely machined according to the three-dimensional heat sealing area contour of the second arc length edge of the arc battery.

[0082] During heat sealing, the conformal heat sealing head closes the mold, and its curved working surface can achieve complete surface contact with the arc-shaped heat sealing area, rather than line or point contact. This allows heat and pressure to be evenly distributed throughout the sealing area, ensuring that every part of the arc-shaped sealing line achieves consistent sealing strength and avoiding localized poor sealing or overpressure damage caused by uneven pressure.

[0083] The edge-folding and finishing process for heat sealing is carried out according to the following procedure: Positioning and preheating: Position the heat-sealed edge outside the second arc length edge that needs to be bent, and use a hot air gun to locally preheat and soften the strip area at its root that needs to be bent (approximately 80°C~120°C, such as 100°C).

[0084] First fold: Using a mechanical folding knife, the preheated heat-sealed edge is folded 90° towards the side of the cavity along the root edge of the arc-shaped cavity sidewall and pressed tightly, so that it initially adheres to the outer surface of the sidewall.

[0085] (Optional) Second fold: If the heat-sealing edge has a large reserved width, it is further folded a second time along the intersection line of the arc-shaped cavity side wall and the bottom surface, so that it is attached to the outer surface of the bottom surface of the cavity.

[0086] Adhesive application and curing: Before, during, or after folding, apply hot melt adhesive by dotting or spraying between the folded edge and the battery casing. Then, use a pressure clamp to fix it and cool it to room temperature to allow it to cure quickly, so that the folded edge and the battery casing are firmly bonded together as a whole.

[0087] Hot melt adhesives have excellent fluidity in the molten state, allowing them to fully fill gaps. After curing, they form a tough sealing layer that effectively resists vibration and impact, and provides waterproofing. Compared to adhesives that require heat curing or UV curing, hot melt adhesives have a simpler process and do not require a long curing time, greatly improving production efficiency.

[0088] It is understood that other types of adhesives, such as epoxy resin adhesives or polyurethane adhesives that require curing, may also be used in other embodiments, but hot melt adhesives are the preferred option in this embodiment due to their rapid molding characteristics.

[0089] Cutting allowance: After the adhesive layer has fully cured, a high-precision milling, cutting, or laser cutting device is used to precisely cut the cured and bonded heat-sealed edge in one go, using the outer wall edge of the arc-shaped cavity as a reference. All excess material exceeding the reference line (including the heat-sealed edge of the aluminum-plastic film shell and the cured adhesive layer) is removed simultaneously. Thus, the 'flat, smooth cut end face' is, microscopically, a cross-section of a composite material. This end face is not solely composed of the aluminum-plastic film, but clearly includes, from the inside out, the cross-section of the heat-sealed edge of the aluminum-plastic film and the cross-section of the cured adhesive layer covering it. After finishing, these two cross-sections are on the same smooth plane, without height differences, burrs, or delamination of the aluminum-plastic film or adhesive layer. This integrated cutting process ensures the integrity, uniformity, and density of the waterproof adhesive layer at the cut end face, completely eliminating the path for moisture to penetrate from the interface between the aluminum-plastic film layer and the adhesive layer, thereby achieving the highest level of edge sealing effect.

[0090] Interference Coating: Using high-precision dispensing equipment, waterproof adhesive (such as modified silicone sealant) is applied along the cut end face using interference coating. The dispensing path and amount are controlled to ensure that the waterproof adhesive completely covers and wraps the entire cut end face, with the adhesive extending at least 2mm beyond the cut end face in all places, forming a reliable secondary sealing barrier and completely eliminating the risk of moisture intrusion from the cut surface.

[0091] To verify the beneficial effects of the above process, the applicant conducted supplementary comparative experiments.

[0092] The experimental group adopted the complete process of this utility model (including folding, conformal heat sealing, edge folding and fine waterproofing process).

[0093] The control group used traditional techniques (manual folding, flat heat sealing, no folded edges, and waterproofing).

[0094] 1000 arc-shaped batteries of the same specification were produced under the same conditions, and the following tests were conducted to obtain the experimental data shown in the table below: Production yield 82.5% 98.8% +16.3% Folding process wrinkle defect rate 9.0% 0.2% -97.8% Heat seal leakage rate 6.1% 0.3% -95.1% Defect rate after folding 8.5% (if applicable) 0% (Adhesive fixing) Completely solve IPX7 waterproof test pass rate not applicable 99.9% Extremely high level Leakage current after storage at 85°C / 85RH high temperature and humidity Far exceeding specifications Meets specifications Significantly improved reliability .

[0095] The above experimental data proves that the complete set of precision processes (contour folding, contour heat sealing, edge gluing, and precision waterproofing) provided by this utility model brings synergistic and unexpected technical effects, which not only significantly improves the first-pass yield rate, but also achieves qualitative progress in sealing reliability and environmental resistance (waterproof and moisture-proof).

[0096] The embodiments described above 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. An arc-shaped battery, characterized in that, Includes a battery cell and an aluminum-plastic film, wherein the battery cell is arc-shaped. An arc-shaped cavity matching the arc shape of the battery cell is formed on the aluminum-plastic film. The arc-shaped cavity is arc-shaped along its length, and the battery cell is confined within the arc-shaped cavity. An aluminum-plastic film extending beyond the first arc-shaped length edge of the opening of the arc-shaped cavity is folded along the first arc-shaped length edge, completely covering the opening of the arc-shaped cavity. This folded aluminum-plastic film adheres to the aluminum-plastic film extending beyond the second arc-shaped length edge and both width edges of the opening of the arc-shaped cavity, forming heat-sealed edges at the two width edges and the second arc-shaped length edge of the opening of the arc-shaped cavity. At each of the heat-sealed edges, the surfaces of the two aluminum-plastic films that are in contact with each other are heat-sealed together to seal the opening of the arc-shaped cavity, forming an aluminum-plastic film shell. The end of the electrode of the battery cell extends from the heat-sealed edge at the wide end, and the electrode is sealed together with the heat-sealed edge, thus sealing the battery cell inside the aluminum-plastic film shell.

2. The arc-shaped battery according to claim 1, characterized in that, The battery cell is a wound battery cell, which is hot-pressed into an arc shape, and the bending direction of the arc is perpendicular to the direction of the winding axis.

3. The arc-shaped battery according to claim 2, characterized in that, The wound battery cell is formed by winding stacked negative electrode sheets, separators, and positive electrode sheets. The ends of the positive and negative electrode sheets are respectively the positive electrode tab welding area and the negative electrode tab welding area exposed for current collectors. On the outer periphery of the wound battery cell, the positive electrode tab welding area and the negative electrode tab welding area are respectively exposed on the outer peripheral surface of the wound battery cell. The positive electrode tab and the negative electrode tab are respectively welded to the positive electrode tab welding area and the negative electrode tab welding area.

4. The arc-shaped battery according to claim 3, characterized in that, The wound cell is formed by winding the negative electrode sheet, the separator, and the positive electrode sheet sequentially stacked from the inside out. On the outer periphery of the wound cell, the end of the negative electrode sheet extends beyond the end of the positive electrode sheet and is wound around the outer periphery of the wound cell.

5. The arc-shaped battery according to claim 4, characterized in that, The positive and negative tabs are opposite each other along the radial direction of the wound cell.

6. The arc-shaped battery according to claim 5, characterized in that, The positive and negative electrodes are symmetrically distributed at 180 degrees.

7. The arc-shaped battery according to claim 1, characterized in that, One tab of the battery cell extends from one width of the aluminum-plastic film shell, and the other tab extends from the other width of the aluminum-plastic film shell.

8. The arc-shaped battery according to claim 1, characterized in that, The outer surface of the closed bottom of the arc-shaped cavity is concave, forming the inner arc of the arc-shaped battery, while the outer surface of the aluminum-plastic film covering the opening of the arc-shaped cavity is convex, forming the outer arc of the arc-shaped battery.

9. The arc-shaped battery according to claim 8, characterized in that, The bottom surface of the arc-shaped cavity is parallel to the aluminum-plastic film covering the opening of the arc-shaped cavity.

10. The arc-shaped battery according to claim 8, characterized in that, The heat-sealed edge, located outside the second arc-shaped length edge of the opening of the arc-shaped cavity, folds along the second arc-shaped length edge toward the side of the arc-shaped cavity and adheres to the outside of the side of the arc-shaped cavity.

11. The arc-shaped battery according to claim 10, characterized in that, An adhesive layer is also bonded between the outer surface of the side of the arc-shaped cavity and the heat-sealed edge of its outer surface.

12. The arc-shaped battery according to claim 10, characterized in that, The heat-sealing width of the heat-sealing edge located outside the second arc-shaped length edge of the opening of the arc-shaped cavity is less than or equal to the thickness of the arc-shaped battery. The length edge of the heat-sealed edge located outside the second arc-shaped length edge of the opening of the arc-shaped cavity does not exceed the intersection edge between the side wall of the arc-shaped cavity and the bottom surface of the arc-shaped cavity.

13. The arc-shaped battery according to claim 10, characterized in that, The heat-sealing width of the heat-sealing edge located outside the second arc-shaped length edge is greater than the thickness of the arc-shaped battery, and less than or equal to the sum of the width and thickness of the arc-shaped battery. The portion of the heat-sealed edge located outside the second arc-shaped length edge, extending beyond the intersecting edge between the sidewall of the arc-shaped cavity and the bottom surface of the arc-shaped cavity, also flips along the intersecting edge toward the bottom surface of the arc-shaped cavity and adheres to the outside of the bottom surface.

14. The arc-shaped battery according to claim 13, characterized in that, An adhesive layer is also bonded between the bottom surface of the arc-shaped cavity and the heat-sealed edge of its outer surface.

15. The arc-shaped battery according to claim 11 or 14, characterized in that, The outer edge of the heat-sealed edge, which is bonded to the outside of the arc-shaped cavity by the adhesive layer, is the cut end face. A waterproof adhesive layer is applied to the cut end face.

16. The arc-shaped battery according to claim 15, characterized in that, The waterproof adhesive layer extends at least 2 mm beyond the cut end face at each point.

17. An electronic product, characterized in that, include, The arc-shaped battery according to any one of claims 1 to 16, The driving circuit is electrically connected to the two electrodes of the arc-shaped battery.

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