Soft pack button battery

Abstract

The present invention relates to a soft-pack button battery, comprising a soft-pack shell and a pole core; the soft-pack shell comprises an upper shell and a lower shell, the upper shell is a first tubular structure with an opening upward, the lower shell is a second tubular structure with an opening upward, the upper shell is embedded in the open end of the lower shell, and the upper shell and the lower shell are sealed and connected to form a sealed cavity between the outer wall of the upper shell and the inner wall of the lower shell, and the pole core is accommodated in the sealed cavity; the pole core comprises a positive electrode sheet, a diaphragm and a negative electrode sheet; the positive electrode sheet leads out a positive electrode ear, and the positive electrode ear passes through the sealed cavity from a first connection position between the upper shell and the lower shell; the negative electrode sheet leads out a negative electrode ear, and the negative electrode ear passes through the sealed cavity from a second connection position between the upper shell and the lower shell. Compared with the prior art, both the upper shell and the lower shell are tubular structures with an opening upward, the upper shell is embedded in the open end of the lower shell, the positive electrode ear and the negative electrode ear can be led out of the sealed cavity along a straight line, and there is no need to bend the positive electrode ear and the negative electrode ear in the sealed cavity, and the positive electrode ear and the negative electrode ear structure are more concise.

Description

Technical Field

[0001] The invention belongs to the technical field of soft-pack batteries, and in particular relates to a soft-pack button battery. Background Art

[0002] Soft-pack batteries are batteries that use polymer (usually aluminum-plastic film) as the outer shell. Compared with hard-shell batteries, soft-pack batteries have the following advantages:

[0003] (1) Good safety. The soft-pack battery structure adopts aluminum-plastic film packaging. When thermal management is out of control or punctured, the aluminum-plastic film shell will provide a buffer space for the battery cell, causing swelling and deformation, and eventually only fire or smoke will occur, but no explosion will occur.

[0004] (2) Light weight and high energy density: Soft-pack batteries are 40% lighter than steel-shell batteries of the same capacity and 20% lighter than aluminum-shell batteries, so they usually have a higher energy density.

[0005] (3) Good electrochemical performance and long life: The internal resistance of soft-pack batteries is small, which can greatly reduce the battery's self-consumption. In addition, soft-pack batteries have a longer cycle life.

[0006] Soft-pack button batteries are a form of soft-pack batteries. The existing soft-pack button batteries have an upper shell, a lower shell and a core, and the positive and negative tabs are led out from the core respectively; when the core is placed between the upper shell and the lower shell for packaging, the positive and negative tabs need to be bent to the side of the core and flattened so that the positive and negative tabs are in the same plane, and then the upper shell and the lower shell are buckled for packaging. Therefore, the tab lead-out of the existing soft-pack button batteries is complicated. Summary of the invention

[0007] The technical problem to be solved by the present invention is: to provide a soft-pack button battery in view of the complex problems caused by the tabs of the existing soft-pack button battery.

[0008] In order to solve the above technical problems, an embodiment of the present invention provides a soft-pack button battery, comprising a soft-pack shell and a pole core;

[0009] The soft-pack shell comprises an upper shell and a lower shell, the upper shell is a first cylindrical structure with an opening facing upward, the lower shell is a second cylindrical structure with an opening facing upward, the upper shell is embedded in the open end of the lower shell, and the upper shell is sealed and connected to the lower shell to form a sealed cavity between the outer wall of the upper shell and the inner wall of the lower shell, and the pole core is accommodated in the sealed cavity;

[0010] The electrode core includes a positive electrode sheet, a diaphragm and a negative electrode sheet; the positive electrode sheet leads to a positive electrode ear, and the positive electrode ear passes through the sealed cavity from a first connection position between the upper shell and the lower shell; the negative electrode sheet leads to a negative electrode ear, and the negative electrode ear passes through the sealed cavity from a second connection position between the upper shell and the lower shell.

[0011] Optionally, the first connection position is 180° apart from the second connection position on the circumference.

[0012] Optionally, the upper shell and the lower shell are respectively formed by stamping of an aluminum-plastic composite film, wherein the aluminum-plastic composite film comprises a PP layer, a nylon layer and an aluminum foil layer sandwiched between the PP layer and the nylon layer;

[0013] The inner layer of the lower shell is a PP layer, and the outer layer of the lower shell is a nylon layer;

[0014] The outer layer of the upper shell is a PP layer, and the inner layer of the upper shell is a nylon layer.

[0015] Optionally, the PP layer of the lower shell and the PP layer of the upper shell are connected as one at other connection positions between the upper shell and the lower shell other than the first connection position and the second connection position by a heat sealing process.

[0016] Optionally, the positive electrode ear and the negative electrode ear are coated with ear glue; at the first connection position and the second connection position, the ear glue is respectively connected to the PP layer of the lower shell and the PP layer of the upper shell by a heat sealing process.

[0017] Optionally, the upper shell includes a first annular portion extending axially along the pole core and a first circular bottom connected below the first annular portion; the lower shell includes a second annular portion extending axially along the pole core and a second circular bottom connected below the second annular portion; the pole core is axially located between the first circular bottom and the second circular bottom.

[0018] Optionally, the first annular portion transitions smoothly to the first circular bottom.

[0019] Optionally, the second annular portion transitions smoothly with the second circular bottom.

[0020] Optionally, the outer end of the positive electrode ear is bent into the cylindrical accommodating cavity of the upper shell and fixed in the cylindrical accommodating cavity of the upper shell;

[0021] The outer end of the negative electrode ear is bent toward the cylindrical accommodation cavity of the upper shell and fixed in the cylindrical accommodation cavity of the upper shell.

[0022] Optionally, it further includes a circuit protection board fixed in the cylindrical accommodating cavity of the upper shell, the positive electrode ear is electrically connected to the circuit protection board, and the negative electrode ear is electrically connected to the circuit protection board.

[0023] Compared with the prior art, the soft-pack button battery provided in the embodiment of the present invention has an upper shell and a lower shell that are both cylindrical structures with an opening upward, and the upper shell is embedded in the open end of the lower shell. The positive electrode ear can pass through the sealed cavity from the gap between the upper shell and the lower shell along the lead-out direction from the positive electrode sheet, and the negative electrode ear can pass through the sealed cavity from the gap between the upper shell and the lower shell along the lead-out direction from the negative electrode sheet. There is no need to bend the positive electrode ear and the negative electrode ear in the sealed cavity. The positive electrode ear and the negative electrode ear can be led out of the sealed cavity along a straight line. The structure of the positive electrode ear and the negative electrode ear is simpler, which avoids the positive electrode ear and the negative electrode ear from being easily broken after bending, reduces the length of the positive electrode ear and the negative electrode ear in the sealed cavity, and reduces the ear resistance. At the same time, an inwardly concave groove is formed on the top of the soft-pack button battery, which can be used to accommodate external structural parts, so that the structural space is maximized. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic cross-sectional structure diagram of a soft-package button battery provided in one embodiment of the present invention;

[0025] Figure 2 It is a schematic cross-sectional structure diagram of a soft-package button battery provided in another embodiment of the present invention.

[0026] The reference numerals in the specification are as follows:

[0027] 1. soft package shell; 11. upper shell; 111. first annular portion; 112. first circular bottom;

[0028] 12. lower shell; 121. second annular portion; 122. second circular bottom;

[0029] 13. Sealed cavity;

[0030] 2. Pole core; 21. Positive electrode sheet; 22. Separator; 23. Negative electrode sheet;

[0031] 3. Positive ear; 4. Negative ear; 5. Ear glue. DETAILED DESCRIPTION

[0032] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0033] like Figure 1 As shown, the soft-pack button battery provided in the embodiment of the present invention comprises a soft-pack shell 1 and a pole core 2;

[0034] The soft-pack shell 1 includes an upper shell 11 and a lower shell 12. The upper shell 11 is a first cylindrical structure with an opening facing upward, and the lower shell 12 is a second cylindrical structure with an opening facing upward. The upper shell 11 is embedded in the open end of the lower shell 12, and the upper shell 11 is sealed and connected to the lower shell 12 to form a sealed cavity 13 between the outer wall of the upper shell 11 and the inner wall of the lower shell 12. The pole core 2 is accommodated in the sealed cavity 13.

[0035] The electrode core 2 includes a positive electrode sheet 21, a diaphragm 22 and a negative electrode sheet 23; the positive electrode sheet 21 leads to a positive electrode ear 3, and the positive electrode ear 3 passes through the sealed cavity 13 from a first connection position between the upper shell 11 and the lower shell 12; the negative electrode sheet 23 leads to a negative electrode ear 4, and the negative electrode ear 4 passes through the sealed cavity 13 from a second connection position between the upper shell 11 and the lower shell 12.

[0036] Compared with the prior art, the soft-pack button battery provided in the embodiment of the present invention has an upper shell 11 and a lower shell 12 that are both cylindrical structures with an opening upward, and the upper shell 11 is embedded in the open end of the lower shell 12. The positive electrode ear 3 can pass through the sealed cavity 13 from the gap between the upper shell 11 and the lower shell 12 along the lead-out direction from the positive electrode sheet 21, and the negative electrode ear 4 can pass through the sealed cavity 13 from the gap between the upper shell 11 and the lower shell 12 along the lead-out direction from the negative electrode sheet 23, so that the positive electrode ear 3 and the negative electrode ear 4 are on the same curve. The positive electrode ear 3 and the negative electrode ear 4 are packaged in the surface, and there is no need to bend the positive electrode ear 3 and the negative electrode ear 4 in the sealed cavity 13. The positive electrode ear 3 and the negative electrode ear 4 can be led out of the sealed cavity 13 in a straight line. The structure of the positive electrode ear 3 and the negative electrode ear 4 is simpler, which avoids the positive electrode ear 3 and the negative electrode ear 4 from being easily broken after bending, reduces the length of the positive electrode ear 3 and the negative electrode ear 4 in the sealed cavity 13, and reduces the ear resistance. At the same time, an inwardly concave groove is formed on the top of the soft-pack button battery, which can be used to accommodate external structural parts, so that the structural space is maximized.

[0037] In one embodiment, if Figure 1 As shown, the pole core 2 is a wound pole core.

[0038] In another embodiment, if Figure 2 As shown, the pole core 2 is a laminated pole core.

[0039] In one embodiment, if Figure 1 As shown, the first connection position and the second connection position differ by 180° on the circumference, which facilitates the lead-out of the positive electrode tab 3 and the negative electrode tab 4 and avoids mutual interference between the positive electrode tab 3 and the negative electrode tab 4 .

[0040] In one embodiment, the upper shell 11 and the lower shell 12 are respectively formed by stamping of an aluminum-plastic composite film, and the aluminum-plastic composite film includes a PP (polypropylene) layer, a nylon layer, and an aluminum foil layer sandwiched between the PP layer and the nylon layer;

[0041] The inner layer of the lower shell 12 is a PP layer, and the outer layer of the lower shell 12 is a nylon layer;

[0042] The outer layer of the upper shell 11 is a PP layer, and the inner layer of the upper shell 11 is a nylon layer; the sealed connection between the upper shell 11 and the lower shell 12 is achieved by sealing the PP layer of the lower shell 12 and the PP layer of the upper shell 11, so that a sealed cavity 13 is formed between the PP layer of the upper shell 11 and the PP layer of the lower shell 12. PP has good corrosion resistance, electrical insulation and plasticity, which prevents the wall of the sealed cavity 13 from being corroded and also facilitates the sealed connection between the upper shell 11 and the lower shell 12.

[0043] During stamping, stamping the aluminum-plastic composite film from the PP layer to the nylon layer is forward stamping, and stamping the aluminum-plastic composite film from the nylon layer to the PP layer is reverse stamping; forward stamping of the aluminum-plastic composite film obtains the lower shell 12, and reverse stamping of the aluminum-plastic composite film obtains the upper shell 11.

[0044] In one embodiment, the upper shell 11 and the lower shell 12 are connected as one with the PP layer of the lower shell 12 and the PP layer of the upper shell 11 at other connection positions other than the first connection position and the second connection position through a heat sealing process; the PP layer of the lower shell 12 and the PP layer of the upper shell 11 are connected more tightly through the heat sealing process, and the pole core 2 is better encapsulated between the upper shell 11 and the lower shell 12, thereby improving the sealing between the upper shell 11 and the lower shell 12.

[0045] In one embodiment, if Figure 1 As shown, the positive electrode ear 3 and the negative electrode ear 4 are both coated with the ear glue 5; at the first connection position and the second connection position, the ear glue 5 is connected to the PP layer of the lower shell 12 and the PP layer of the upper shell 11 respectively through a heat sealing process; the ear glue 5 is arranged so that the positive electrode ear 3 will not directly contact the upper shell 11 and the lower shell 12 at the first connection position and the negative electrode ear 4 will not directly contact the upper shell 11 and the lower shell 12 at the second connection position, so as to avoid a short circuit inside the soft-pack button battery.

[0046] In one embodiment, if Figure 1 As shown, the upper shell 11 includes a first annular portion 111 extending along the axial direction of the pole core 2 and a first circular bottom 112 connected below the first annular portion 111; the lower shell 12 includes a second annular portion 121 extending along the axial direction of the pole core 2 and a second circular bottom 122 connected below the second annular portion 121; the pole core 2 is axially located between the first circular bottom 112 and the second circular bottom 122; the upper shell 11 is embedded in the lower shell 12, so that the first annular portion 111 and the second annular portion 121 are sealed and connected to achieve a sealed connection between the upper shell 11 and the lower shell 12; compared with the existing soft-pack button battery in which the upper and lower shells 12 are buckled together, there is no need to set a folding edge to achieve a sealed connection between the upper shell 11 and the lower shell 12, and the diameter of the soft-pack button battery will not be increased, and the space in the diameter direction of the soft-pack button battery can be maximized, thereby improving the energy density of the soft-pack button battery.

[0047] The aluminum-plastic composite film is forwardly stamped to form a first tubular structure, and then the aluminum-plastic composite film extending outward from the opening end of the first tubular structure is cut off to obtain a lower shell 12; the aluminum-plastic composite film is reversely stamped to form a second tubular structure, and then the aluminum-plastic composite film extending outward from the opening end of the second tubular structure is cut off to obtain an upper shell 11.

[0048] In one embodiment, if Figure 1 As shown, the first annular portion 111 and the first circular bottom 112 have a smooth transition, which avoids a sudden change in the connection between the first annular portion 111 and the first circular bottom 112 , which may cause the connection to puncture the lower shell 12 or scratch the pole core 2 .

[0049] Specifically, there is an arc-shaped transition between the first annular portion 111 and the first circular bottom 112 .

[0050] In one embodiment, if Figure 1 As shown, the second annular portion 121 and the second circular bottom 122 have a smooth transition, thereby avoiding a sudden change in the connection between the second annular portion 121 and the second circular bottom 122 , which would cause the connection to puncture the upper shell 11 or scratch the pole core 2 .

[0051] Specifically, there is an arc-shaped transition between the second annular portion 121 and the second circular bottom 122 .

[0052] In one embodiment, the outer end of the positive electrode tab 3 is bent toward the cylindrical accommodation cavity of the upper shell 11 and fixed in the cylindrical accommodation cavity of the upper shell 11;

[0053] The outer end of the negative electrode ear 4 is bent toward the cylindrical accommodating cavity of the upper shell 11 and fixed in the cylindrical accommodating cavity of the upper shell 11; it can better protect the positive electrode ear 3 and the negative electrode ear 4, facilitate the connection of the positive electrode ear 3 with other electronic components and the connection of the negative electrode ear 4 with other electronic components, and improve the stability of the electrical connection of the soft-pack button battery.

[0054] In one embodiment, it also includes a circuit protection board fixed in the cylindrical accommodating cavity of the upper shell 11, the positive electrode ear 3 is electrically connected to the circuit protection board, and the negative electrode ear 4 is electrically connected to the circuit protection board; the safety of the soft-pack button battery is improved, and the circuit protection board can be controlled to break the circuit inside the soft-pack button battery to avoid damage to the pole core 2.

[0055] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A soft-pack button battery, characterized in that: It includes a soft-pack shell, a circuit protection board and a pole core; The soft-pack shell comprises an upper shell and a lower shell, the upper shell is a first cylindrical structure with an opening facing upward, the lower shell is a second cylindrical structure with an opening facing upward, the upper shell is embedded in the open end of the lower shell, and the upper shell is sealed and connected to the lower shell to form a sealed cavity between the outer wall of the upper shell and the inner wall of the lower shell, and the pole core is accommodated in the sealed cavity; The electrode core comprises a positive electrode sheet, a separator and a negative electrode sheet; the positive electrode sheet leads to a positive electrode ear, and the positive electrode ear passes through the sealed cavity from a first connection position between the upper shell and the lower shell; the negative electrode sheet leads to a negative electrode ear, and the negative electrode ear passes through the sealed cavity from a second connection position between the upper shell and the lower shell; The outer end of the positive electrode ear is bent into the cylindrical accommodation cavity of the upper shell and fixed in the cylindrical accommodation cavity of the upper shell; the outer end of the negative electrode ear is bent into the cylindrical accommodation cavity of the upper shell and fixed in the cylindrical accommodation cavity of the upper shell; The circuit protection board is fixed in the cylindrical accommodating cavity of the upper shell, the positive electrode ear is electrically connected to the circuit protection board, and the negative electrode ear is electrically connected to the circuit protection board; The positive electrode tab passes through the sealed cavity from the gap between the upper shell and the lower shell along the lead-out direction of the positive electrode sheet, and the negative electrode tab passes through the sealed cavity from the gap between the upper shell and the lower shell along the lead-out direction of the negative electrode sheet; The upper shell and the lower shell are respectively formed by stamping of an aluminum-plastic composite film, wherein the aluminum-plastic composite film comprises a PP layer, a nylon layer and an aluminum foil layer sandwiched between the PP layer and the nylon layer; The inner layer of the lower shell is a PP layer, and the outer layer of the lower shell is a nylon layer; The outer layer of the upper shell is a PP layer, and the inner layer of the upper shell is a nylon layer; The upper shell and the lower shell are connected together at other connection positions other than the first connection position and the second connection position by heat sealing process to connect the PP layer of the lower shell and the PP layer of the upper shell into one piece; The positive electrode ear and the negative electrode ear are both coated with ear glue; at the first connection position and the second connection position, the ear glue is connected to the PP layer of the lower shell and the PP layer of the upper shell respectively through a heat sealing process.

2. The soft-pack button battery according to claim 1, characterized in that: The first connection position and the second connection position differ from each other by 180° on the circumference.

3. The soft-pack button battery according to claim 1, characterized in that: The upper shell includes a first annular portion extending along the axial direction of the pole core and a first circular bottom connected below the first annular portion; the lower shell includes a second annular portion extending along the axial direction of the pole core and a second circular bottom connected below the second annular portion; the pole core is axially located between the first circular bottom and the second circular bottom.

4. The soft-pack button battery according to claim 3, characterized in that: The first annular portion transitions smoothly with the first circular bottom.

5. The soft-pack button battery according to claim 3, characterized in that: The second annular portion transitions smoothly with the second circular bottom.

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