Battery structure and manufacturing method for the same

Abstract

To provide a button battery structure that can effectively increase energy density within a limited volume.SOLUTION: The battery structure includes a case 10, a cap assembly 20, and an electrode assembly. An accommodation chamber is provided in the case. The electrode assembly is placed in the accommodation chamber. The accommodation chamber is further filled with an electrolyte. The electrode assembly is provided with two electrodes. One of the electrodes is electrically connected to the cap assembly. The other of the electrodes is electrically connected to the case. The case is connected to a side wall in a combination with the cap assembly. This invention reduces a wall thickness in comparison with a multi-layered side wall of a conventional button battery, effectively increases volume of the accommodation chamber and increases an amount of electrolyte filling, so as to enable effectively increasing battery energy density.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to the field of battery technology, and in particular to a battery structure and a method for manufacturing the same. [Background technology]

[0002] Rechargeable lithium-ion batteries, such as button batteries in mobile phones and Bluetooth earphones, are widely used in handheld electronic devices. In small and sensitive devices, such as hearing aids, wireless Bluetooth earphones, electronic watches, gastrointestinal scope equipment, etc., the volumetric energy density of the battery is an important consideration.

[0003] Conventional button batteries generally use a double-tube upper case and a lower case, which are stacked and fitted together, and then a sealing insulation layer is provided in between. The button battery has a limited overall volume, and the upper case, the lower case, and the sealing insulation layer have thicknesses, so the only way to ensure that the overall volume does not change is to compress the volume of the battery cavity, and the battery energy density cannot be increased. Therefore, increasing the energy density within a limited volume is an issue that needs to be resolved as soon as possible. Summary of the Invention [Problem to be solved by the invention]

[0004] It is an object of the present invention to overcome the deficiencies of the prior art and provide a battery structure and a method for manufacturing the same. [Means for solving the problem]

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions.

[0006] In a first aspect, an embodiment of the present invention provides a battery structure, comprising a case, a cap assembly, and an electrode assembly, a chamber is provided within the case, the electrode assembly is placed in the chamber, and the chamber is further filled with an electrolyte, two electrodes are provided on the electrode assembly, one of the electrodes is electrically connected to the cap assembly, and the other of the electrodes is electrically connected to the case, and the case is connected to a sidewall in combination with the cap assembly.

[0007] In one specific embodiment, the cap assembly includes a lid body, a retaining plate, and an insulating layer, the insulating layer being located between the lid body and the retaining plate, the lid body having an opening, the retaining plate having a boss, the boss protruding from the opening, and the case being connected to the lid body.

[0008] In one specific embodiment, the case has an upper end surface, a connecting wall extends from the cover, the connecting wall has a lower end surface, and the upper end surface is connected to the lower end surface.

[0009] In one particular embodiment, the upper end surface and the lower end surface are welded to provide a sealed connection.

[0010] In one specific embodiment, the thickness of the connecting wall is the same as the thickness of the case.

[0011] In one specific embodiment, the thickness of the case is 0.1 mm to 0.25 mm.

[0012] In one specific embodiment, the insulating layer is an insulating ring, and the width of the insulating ring is greater than the width of an overlap between the pressing plate and the lid.

[0013] In one specific embodiment, the width of the overlap between the pressing plate and the lid is 0.5 mm to 10 mm.

[0014] In one specific embodiment, the case is cylindrical and has an elliptical, rectangular or heart-shaped cross section.

[0015] The beneficial effects of the battery structure of the present invention compared with the prior art are as follows: a receiving chamber is provided in the case, an electrode assembly is placed in the receiving chamber, the receiving chamber is further filled with an electrolyte, the electrode assembly is provided with two electrodes, one of the electrodes is electrically connected to the cap assembly, the other of the electrodes is electrically connected to the case, and the case is combined with the cap assembly and connected to the side wall, thereby reducing the wall thickness compared with the multi-layered side wall of the conventional button battery, effectively increasing the volume of the receiving chamber and increasing the filling amount of the electrolyte, thereby effectively improving the battery energy density.

[0016] In a second aspect, an embodiment of the present invention provides a method for manufacturing the above battery structure, including the steps of inserting an insulating layer between a lid body and a backing plate, assembling the lid body and the backing plate, and heating and cooling to form a cap assembly; inserting an electrode assembly into a case, and electrically connecting two electrodes of the electrode assembly to the cap assembly and the case, respectively; injecting an electrolyte into the case, and welding and sealing the cap assembly and the case to complete the manufacture of the battery structure.

[0017] The advantageous effects of the manufacturing method of the battery structure of the present invention compared with the prior art are as follows: an insulating layer is inserted between the cover body and the backing plate, the cover body and the backing plate are assembled, heated and cooled to form a cap assembly, and then the two electrodes of the electrode assembly are electrically connected to the cap assembly and the case respectively, and finally the electrolyte is injected into the case, and the cap assembly and the case are welded and sealed to complete the manufacturing of the battery structure, thereby reducing the wall thickness compared with the multi-layered side walls of the conventional button battery, effectively increasing the volume of the receiving chamber and increasing the filling amount of the electrolyte, and thereby effectively improving the battery energy density.

[0018] The invention will now be further described with reference to the accompanying drawings and specific embodiments. [Brief description of the drawings]

[0019] In order to more clearly describe the technical solutions in the embodiments of the present invention, the following briefly describes the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention, and those skilled in the art can also obtain other drawings based on these drawings without paying creative labor.

[0020] [Figure 1] 1 is a schematic diagram of a battery structure according to an embodiment of the present invention; [Diagram 2] 1 is a schematic cross-sectional view of a battery structure according to an embodiment of the present invention. [Diagram 3] 1 is an explosion schematic diagram of a battery structure according to an embodiment of the present invention; [Figure 4] 4 is a flow chart of a method for manufacturing a battery structure according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be described in more detail below in conjunction with the accompanying drawings and specific embodiments.

[0022] Hereinafter, the technical solutions in the embodiments of the present invention will be described clearly and completely in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative labor belong to the scope of protection of the present invention.

[0023] In describing the present invention, the orientations or positional relationships indicated by terms such as "center," "longitudinal," "lateral," "length," "width," "thickness," "top," "bottom," "front," "rear," "left," "right," "vertical," "horizontal," "upper," "bottom," "inner," "outer," "clockwise," "counterclockwise," and the like are based on the orientations or positional relationships indicated in the drawings, and are merely for the purpose of facilitating and simplifying the description of the present invention, and do not indicate or suggest that the devices or elements shown must have a specific orientation, be configured and operate in a specific orientation, and should not be understood as limitations on the present invention.

[0024] Furthermore, the terms "first" and "second" are used for descriptive purposes only and cannot be understood to denote or suggest a relative importance or to imply a number of the technical features depicted. Thus, a feature qualified as "first" or "second" may explicitly or implicitly include one or more features. In the description of the present invention, "plurality" means two or more unless otherwise expressly and specifically limited.

[0025] In the present invention, unless otherwise clearly specified and limited, the terms "attached", "connected", "coupled", "fixed" and the like should be understood in a broad sense. For example, it may be a connection, a detachable connection, or an integral connection. It may be a mechanical connection or an electrical connection. It may be a direct connection, an indirect connection via an intermediate medium, an internal connection of two elements, or an interactive relationship between two elements. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific situation.

[0026] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature can include direct contact between the first and second features, and can also include contact between the first and second features not directly but through another feature between them. Furthermore, a first feature being "above," "above," and "on the upper surface" of a second feature only indicates that the first feature is directly above and diagonally above the second feature, or that the horizontal height of the first feature is higher than that of the second feature. A first feature being "below," "below," and "on the lower surface" of a second feature only indicates that the first feature is directly below and diagonally below the second feature, or that the horizontal height of the first feature is smaller than that of the second feature.

[0027] In the present description, reference to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In the present description, general expressions of the above terms should not necessarily be understood to be for the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described can be combined in any suitable manner in any one or more embodiments or examples. Furthermore, one skilled in the art can combine or combine different embodiments or examples described herein.

[0028] As shown in FIG. 1 to FIG. 3, the present invention discloses a battery structure, which includes a case 10, a cap assembly 20, and an electrode assembly 30, a chamber 11 is provided in the case 10, the electrode assembly 30 is placed in the chamber 11, and the chamber 11 is further filled with an electrolyte (not shown), two electrodes are provided in the electrode assembly 30, one of the electrodes is electrically connected to the cap assembly 20, and the other of the electrodes is electrically connected to the case 10, and the case 10 is combined with the cap assembly 20 and connected to a side wall.

[0029] In one embodiment, the electrodes include a positive electrode 31 and a negative electrode 32. The positive electrode 31 is electrically connected to the cap assembly 20 or the case 10. The negative electrode 32 is electrically connected to the case 10 or the cap assembly 20. It is preferred that the positive electrode 31 is electrically connected to the cap assembly 20 and the negative electrode 32 is electrically connected to the case 10.

[0030] Specifically, in this battery structure, a chamber 11 is provided in a case 10, an electrode assembly 30 is placed in the chamber 11, the chamber 11 is further filled with an electrolyte, the electrode assembly 30 is provided with two electrodes, one of the electrodes is electrically connected to the cap assembly 20, the other of the electrodes is electrically connected to the case 10, and the case 10 is combined with the cap assembly 20 and connected to a side wall to achieve sealing. Compared with the multi-layered side walls of a conventional button battery, the wall thickness is reduced, and the volume of the chamber 11 is effectively increased to increase the amount of electrolyte filled, thereby effectively improving the battery energy density.

[0031] Specifically, the electrolyte used is of the conventional technology and will not be described in detail here.

[0032] In one embodiment, the cap assembly 20 includes a lid body 21, a pressure plate 22, and an insulating layer 23, the insulating layer 23 is located between the lid body 21 and the pressure plate 22, an opening 211 is provided in the lid body 21, a boss 221 is provided in the pressure plate 22, the boss 221 protrudes from the opening 211, and the case 10 is connected to the lid body 21.

[0033] Specifically, the insulating layer 23 is provided between the lid 21 and the pressure plate 22 to perform the functions of insulation and sealing. The lid 21 and the pressure plate 22 are all made of metal. The lid 21, the pressure plate 22, and the insulating layer 23 are formed by heating the metal using high-frequency induction, so that the insulating layer 23 reaches a molten state and adheres to the lid 21 and the pressure plate 22, and is integrated after cooling, providing good sealing and insulating effects. In other embodiments, the cap assembly 20 can be heated to a constant temperature using a heating block or heating equipment, or a combination of the above two heating methods can be used to achieve the same effect.

[0034] Preferably, both the cover 21 and the presser plate 22 are made of stainless steel material, which has high strength and excellent corrosion resistance.

[0035] Furthermore, in practical use, when high temperatures occur inside the battery structure, the insulating layer 23 goes into a molten state, creating a gap between the lid 21 and the pressure plate 22, allowing gas inside the battery structure to flow out along the gap, reducing the possibility of explosion and providing an explosion-proof effect.

[0036] In one embodiment, the case 10 has an upper end surface 12, a connecting wall 212 extends from the cover 21, the connecting wall 212 has a lower end surface (not shown), and the upper end surface 12 is connected to the lower end surface.

[0037] Specifically, a connection wall 212 having a lower end surface extends from the cover 21, the upper end surface 12 is connected to the lower end surface, the connection wall 212 and the case 10 are butted together to form a good weld line, and the upper end surface 12 and the lower end surface are sealed by welding. This battery structure is laser-welded from the side, and the yield rate can be effectively increased. Preferably, docking welding is used to increase the volume of the battery storage chamber 11. A laser method is used for welding, and the specific welding parameters are as follows: welding current is 15 to 50 A, pulse width is 0.5 to 5 ms, frequency / duty ratio is 40 / 50%, starting speed is 10 to 25 mm / s, processing speed is 5 to 200 mm / s, and acceleration is 5 to 20 mm / s. 2The spot diameter is 0.1 to 0.5 mm.

[0038] In one embodiment, the thickness of the connecting wall 212 is the same as that of the case 10, so that the contact surfaces of the two are consistent, thereby improving the welding effect between the cover 21 and the case 10 and improving the sealing effect.

[0039] In one embodiment, the specific thickness value of the case 10 can be set as necessary and is not particularly limited here. Preferably, the thickness of the case 10 is 0.1 mm to 0.25 mm.

[0040] In one embodiment, the insulating layer 23 is an insulating ring, and the width of the insulating ring is greater than the width of the overlap between the pressing plate 22 and the lid body 21 .

[0041] Specifically, in order to provide good insulation, the insulating ring is designed to be annular in shape to match the cover 21 and the pressing plate 22, and the width of the insulating ring is designed to be greater than the overlapping width of the pressing plate 22 and the cover 21. Moreover, the insulating ring cannot cover the area of ​​the boss 221.

[0042] Preferably, the insulating layer 23 is made of a three-ply polypropylene material that has good insulating and sealing properties.

[0043] In one embodiment, the overlap width between the pressing plate 22 and the lid 21 is 0.5 mm to 10 mm. The overlap width is the width of the sealing line of the battery.

[0044] Specifically, the specific thickness value of the overlapping width between the pressing plate 22 and the lid body 21 can be set as necessary, and is not specifically limited here. Preferably, the overlapping width is 0.5 mm to 10 mm.

[0045] In one embodiment, the case 10 is cylindrical and its cross section is elliptical, square, heart-shaped, etc., in order to adapt to different scenes.

[0046] In one embodiment, the electrodes include a positive electrode 31 made of aluminum foil and a negative electrode 32 made of copper foil.

[0047] Specifically, the positive electrode 31 and the negative electrode 32 are separated by a battery separator, and the electrode assembly 30 is fabricated by a spiral winding or stacking method, and the electrode assembly 30 realizes an energy storage function. Note that the battery separator refers to a film made of plastic such as polypropylene.

[0048] Specifically, the active material is uniformly applied to both sides of an aluminum foil having a thickness of 0.06 to 0.016 mm to form the positive electrode 31. The active material is uniformly applied to both sides of a copper foil having a thickness of 0.06 to 0.012 mm to form the negative electrode 32. Examples of the active material include lithium cobalt oxide, lithium titanate, and graphite. Lithium cobalt oxide and lithium titanate are used for the positive electrode 31, and graphite is used for the negative electrode 32.

[0049] Preferably, the positive electrode 31 is electrically connected to a boss 221 for outputting power to the outside, and the negative electrode 32 is electrically connected to the bottom of the case 10 to form an electric cycle.

[0050] Referring to FIG. 4, the present invention also discloses a method for manufacturing the above battery structure, which includes the following steps.

[0051] In S1, an insulating layer is placed between the lid and the backing plate, and the lid and backing plate are assembled, heated, and cooled to form a cap assembly.

[0052] In one embodiment, if necessary, a mold is used to press the cover, pressure plate, and case as a spare, a mold of a corresponding shape is used to prepare a spare sealing insulating rubber on the sheet insulating layer, and if necessary, a spare electrode assembly of a corresponding shape and size is prepared.

[0053] Specifically, the prepared insulating layer is placed between the lid body and the pressing plate, and the lid body and the pressing plate are assembled, and then combined by means of a jig or other equipment to form a cap assembly. The specific process parameters that were set are shown in Table 1.

[0054] [Table 1]

[0055] In S2, the electrode assembly is placed in the case, and the two electrodes of the electrode assembly are electrically connected to the cap assembly and the case, respectively.

[0056] Specifically, the electrode assembly is placed in a case, the positive electrode is electrically connected to the boss, and the negative electrode is electrically connected to the case.

[0057] Here, the electrical connection is made by resistance welding or laser welding. Specifically, the resistance welding parameters are shown in Table 2.

[0058] [Table 2]

[0059] Specifically, after step S2, the electrically connected semi-finished product is further baked in a high vacuum environment for dehumidification. Specific parameters are shown in Table 3.

[0060] [Table 3]

[0061] In S3, an electrolyte is injected into the case, and the cap assembly and the case are hermetically welded to complete the manufacture of the battery structure.

[0062] Specifically, the electrolyte is injected into the case, and after that, the contact surfaces of the lid and the case are welded using a laser in an environment with a relative humidity of less than 1%, completing the battery package. The laser welding parameters are shown in Table 4.

[0063] [Table 4]

[0064] Specifically, after S4, the method further includes activating, forming and dissolving the welded battery to complete the battery fabrication, where activation refers to leaving the battery to allow the electrolyte to fully permeate the electric core after injection, formation refers to precharging the battery to activate it, and dissolving refers to testing the battery capacity.

[0065] Here, a comparison of the performance of a battery manufactured using the present invention and a conventional button battery is shown, for example, in Table 5.

[0066] [Table 5]

[0067] The manufacturing method of the battery structure of the present invention includes inserting an insulating layer between the lid body and the pressing plate, assembling the lid body and the pressing plate, heating and cooling to form a cap assembly, electrically connecting the two electrodes of the electrode assembly to the cap assembly and the case respectively, and finally injecting an electrolyte into the case, and welding and sealing the cap assembly and the case to complete the manufacture of the battery structure, thereby reducing the wall thickness compared to the multi-layered side walls of conventional button batteries, effectively increasing the volume of the storage chamber and increasing the filling amount of the electrolyte, and thereby effectively improving the battery energy density.

[0068] The battery structure of the present invention has the characteristics of simple structure, low manufacturing cost, and excellent sealing performance, while at the same time allowing the volume of the battery chamber to be increased and allowing the battery to have a variety of shapes.

[0069] The above-mentioned embodiments are the preferred embodiments of the present invention, in addition, the present invention can be realized in other ways. Without departing from the concept of the present invention, any obvious substitutions are within the protection scope of the present invention.

[0070] (Additional Note) (Appendix 1) a case, a cap assembly, and an electrode assembly, a chamber is provided in the case, the electrode assembly is placed in the chamber, the chamber is further filled with an electrolyte, two electrodes are provided on the electrode assembly, one of the electrodes is electrically connected to the cap assembly, the other of the electrodes is electrically connected to the case, and the case is connected to a side wall in combination with the cap assembly; A battery structure comprising:

[0071] (Appendix 2) the cap assembly includes a lid, a pressing plate, and an insulating layer, the insulating layer being located between the lid and the pressing plate, the lid having an opening, the pressing plate having a boss, the boss protruding from the opening, and the case being connected to the lid; 2. A battery structure as described in claim 1.

[0072] (Appendix 3) The case has an upper end surface, a connecting wall extends from the cover, the connecting wall has a lower end surface, and the upper end surface is connected to the lower end surface. 3. The battery structure of claim 2.

[0073] (Appendix 4) The upper end surface and the lower end surface are welded to provide a sealed connection. 4. The battery structure of claim 3.

[0074] (Appendix 5) The thickness of the connecting wall is the same as the thickness of the case. 4. The battery structure of claim 3.

[0075] (Appendix 6) The thickness of the case is 0.1 mm to 0.25 mm. 6. The battery structure of claim 5.

[0076] (Appendix 7) the insulating layer is an insulating ring, and the width of the insulating ring is greater than the width where the pressing plate and the lid body overlap; 3. The battery structure of claim 2.

[0077] (Appendix 8) The width where the pressing plate and the lid overlap is 0.5 mm to 10 mm. 8. The battery structure of claim 7.

[0078] (Appendix 9) The case is cylindrical and has an elliptical, rectangular or heart-shaped cross section. 3. The battery structure of claim 2.

[0079] (Appendix 10) A method for producing a battery structure according to any one of claims 2 to 9, comprising: placing an insulating layer between the lid and the backing plate, assembling the lid and the backing plate, and heating and cooling to form a cap assembly; placing the electrode assembly in a case and electrically connecting two electrodes of the electrode assembly to the cap assembly and the case, respectively; injecting an electrolyte into the case and welding the cap assembly and the case together to complete the manufacture of the battery structure. A method for manufacturing a battery structure comprising the steps of:

Claims

1. a case, a cap assembly, and an electrode assembly, a chamber is provided in the case, the electrode assembly is placed in the chamber, the chamber is further filled with an electrolyte, two electrodes are provided on the electrode assembly, one of the electrodes is electrically connected to the cap assembly, the other of the electrodes is electrically connected to the case, and the case is connected to a side wall in combination with the cap assembly; A battery structure comprising:

2. the cap assembly includes a lid, a pressing plate, and an insulating layer, the insulating layer being located between the lid and the pressing plate, the lid having an opening, the pressing plate having a boss, the boss protruding from the opening, and the case being connected to the lid; 2. The battery structure of claim 1.

3. The case has an upper end surface, a connecting wall extends from the cover, the connecting wall has a lower end surface, and the upper end surface is connected to the lower end surface.

3. The battery structure of claim 2.

4. The upper end surface and the lower end surface are welded to provide a sealed connection.

4. The battery structure of claim 3.

5. The thickness of the connecting wall is the same as the thickness of the case.

4. The battery structure of claim 3.

6. The thickness of the case is 0.1 mm to 0.25 mm.

6. The battery structure of claim 5.

7. the insulating layer is an insulating ring, and the width of the insulating ring is greater than the width where the pressing plate and the lid body overlap; 3. The battery structure of claim 2.

8. The width at which the pressing plate and the lid body overlap is 0.5 mm to 10 mm.

8. The battery structure of claim 7.

9. The case is cylindrical and has an elliptical, rectangular or heart-shaped cross section.

3. The battery structure of claim 2.

10. A method for producing a battery structure according to any one of claims 2 to 9, comprising the steps of: placing an insulating layer between the lid and the backing plate, assembling the lid and the backing plate, and heating and cooling to form a cap assembly; placing the electrode assembly in a case and electrically connecting two electrodes of the electrode assembly to the cap assembly and the case, respectively; injecting an electrolyte into the case and welding the cap assembly and the case together to complete the manufacture of the battery structure. A method for manufacturing a battery structure comprising the steps of:

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