A steel shell button battery heat sealing mold and manufacturing method

Abstract

The invention discloses a steel shell button battery heat-sealing mold and a manufacturing method thereof, the heat-sealing mold comprising an upper top mold for sealing a positive electrode shell and a lower top mold for sealing a negative electrode shell, a sealing mold is arranged between the upper top mold and the lower top mold, a groove is arranged on the outer side of the sealing mold, a heating device for heating the sealing mold is arranged inside the groove, a first circular hole is arranged at one end of the middle part of the sealing mold for accommodating the upper top mold to move up and down, and a second circular hole is arranged at the other end for accommodating the lower top mold to move up and down, an annular boss is arranged at the end of the first circular hole for pressing the end of the positive electrode shell into an arc shape, the annular boss comprises a first end face and a second end face, the diameter of the first end face is larger than the diameter of the second end face, and the annular boss is large at the upper end and small at the lower end. The invention can improve the sealing performance of the steel shell button battery, reduce the undesirable phenomenon caused by poor fusion of the sealing port, and improve the yield rate and production efficiency of the steel shell button battery.

Description

Technical Field

[0001] The invention relates to the technical field of steel shell button type batteries, and in particular to a heat sealing mold for steel shell button type batteries and a manufacturing method thereof. Background Art

[0002] A button cell, also known as a button battery, is a battery that looks like a small button. Generally speaking, it has a larger diameter and a thinner thickness (compared to cylindrical batteries such as No. 5 AA batteries on the market). Button cells are classified based on their appearance. The corresponding battery categories include cylindrical batteries, square batteries, special-shaped batteries, etc.

[0003] The positive and negative shells of existing button-type lithium batteries are generally formed by stamping steel plates to form the positive and negative shells of the battery. The packaging of button-type lithium batteries adopts pressure packaging. After packaging, there is a large compressive stress at the seal of the positive and negative shells. If the general packaging method is used, the positive and negative shells and the sealing rings are not well fused, and the gap between the assemblies is not well controlled, which can easily cause poor sealing performance of the battery and a high scrap rate. When the battery heats up during use and expands slightly, it will cause the seal to crack, causing the electrolyte to flow out, thereby causing battery damage. Summary of the invention

[0004] The purpose of the present invention is to overcome the above-mentioned defects in the prior art and provide a steel shell button battery heat sealing mold and a manufacturing method, which can improve the sealing performance of the steel shell button battery, make the positive electrode shell and the negative electrode shell fit more tightly, reduce the adverse phenomena caused by poor fusion of the sealing mouth, and improve the yield and production efficiency of the steel shell button battery.

[0005] To achieve the above-mentioned purpose, the present invention provides a steel shell button battery heat sealing mold, the heat sealing mold comprises an upper top mold for sealing the positive electrode shell and a lower top mold for sealing the negative electrode shell, a sealing mold is arranged between the upper top mold and the lower top mold, a groove is arranged on the outer side of the sealing mold, a heating device for heating the sealing mold is arranged inside the groove, a first circular hole for accommodating the upper top mold to move up and down is arranged at one end of the middle part of the sealing mold, and a second circular hole for accommodating the lower top mold to move up and down is arranged at the other end, an annular boss for pressing the end of the positive electrode shell into a circular arc shape is arranged at the end of the first circular hole, the annular boss comprises a first end face and a second end face, the diameter of the first end face is larger than the diameter of the second end face, and the annular boss is larger at the upper end and smaller at the lower end.

[0006] Preferably, the groove is in a spiral shape, the heating device is a spiral heating tube, and the heating device is provided with a first terminal and a second terminal.

[0007] Preferably, the heating device is controlled by a temperature controller module.

[0008] Preferably, the sealing mold is provided with a first chamfer around it, the upper end of the first circular hole is provided with a first arc for guiding the upper top mold, the lower end of the first circular arc is provided with a second chamfer, and the lower end of the second circular hole is provided with a third chamfer for guiding the lower top mold.

[0009] Preferably, the diameter of the upper top mold is larger than the diameter of the lower top mold, and the diameter of the first circular hole is larger than the diameter of the second circular hole.

[0010] Preferably, the diameter of the second end surface is smaller than the diameter of the second circular hole.

[0011] The present invention also provides a method for manufacturing a steel shell button type battery by using a steel shell button type battery heat sealing mold, comprising the following steps:

[0012] Step S1, manufacturing a positive electrode shell and a negative electrode shell; stamping a steel foil with a thickness of 2-3 mm using a production mold, so that the manufactured positive electrode shell and negative electrode shell have grooves that are mutually compatible with the positive electrode sheet and the negative electrode sheet, and the openings have bent edges that can be engaged with each other;

[0013] Step S2, manufacturing positive electrode sheets and negative electrode sheets; coating the positive electrode slurry on the positive electrode collector, coating, shaping and drying, punching it into corresponding shapes with a punching machine to make positive electrode sheets, coating the negative electrode slurry on the negative electrode collector, coating, shaping and drying, punching it into corresponding shapes with a punching machine to make negative electrode sheets;

[0014] Step S3, welding the tabs to form a battery cell; welding the positive tab on the positive electrode sheet, welding the negative tab on the negative electrode sheet, forming a battery cell with the positive electrode sheet, the separator and the negative electrode sheet, installing a sealing ring between the positive electrode shell and the negative electrode shell, welding all the positive tabs inside the battery cell together and welded to the surface of the positive electrode shell, welding all the negative tabs inside the battery cell together and welded to the surface of the negative electrode shell, and installing the battery cell into the grooves of the positive electrode shell and the negative electrode shell;

[0015] Step S4, heat sealing is performed using a heat sealing mold; the positive electrode shell and the negative electrode shell are snap-fitted and fastened to form a battery shell, the above battery shell is placed in a sealing mold, the heating device is controlled to a suitable temperature by a temperature controller module, the press pushes the upper mold downward to extrude the positive electrode shell, the heating device heats the sealing ring, and after the sealing ring is heated and softened, it is extruded by the pressure of the heat sealing mold to complement the wrinkles or cracks between the positive electrode shell and the negative electrode shell, and the sealing ring fills the wrinkles or cracks between the positive electrode shell and the negative electrode shell.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] 1. An arc-shaped annular boss is provided at the end of the first circular hole of the present invention, which can press the end of the positive electrode shell into an arc shape, press the end of the positive electrode shell into the turning point of the negative electrode shell, and at the same time, the positive electrode shell presses the sealing ring to deform the sealing ring, and the positive electrode shell, the sealing ring and the negative electrode shell are connected together, which can improve the sealing performance of the steel shell button battery and make the positive electrode shell and the negative electrode shell more tightly buckled.

[0018] 2. The outer ring of the sealing mold of the present invention is provided with a heating device, and the heating device heats the sealing ring. After the sealing ring is heated and softened, it is squeezed by the pressure of the heat sealing mold to complement the wrinkles or cracks between the positive electrode shell and the negative electrode shell. The sealing ring fills the wrinkles or cracks between the positive electrode shell and the negative electrode shell to achieve gapless packaging, thereby more effectively improving the sealing effect of the steel shell button battery, reducing the adverse phenomena caused by poor fusion of the sealing port, and improving the yield and production efficiency of the steel shell button battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 It is a schematic diagram of the overall structure of a heat-sealing mold for a steel shell button-type battery provided by the present invention;

[0021] Figure 2 It is a top view of a heat-sealing mold for a steel shell button-type battery provided by the present invention;

[0022] Figure 3 It is a schematic cross-sectional structure diagram of a heat-sealing mold for a steel shell button-type battery provided by the present invention;

[0023] Figure 4 yes Figure 3 The enlarged schematic diagram of middle Ⅰ;

[0024] Figure 5 yes Figure 4 The enlarged schematic diagram of middle Ⅱ;

[0025] Figure 6 It is a schematic diagram of the cross-sectional structure of a steel shell button type battery provided by the present invention;

[0026] Figure 7 It is a schematic diagram of the steps of a method for manufacturing a steel shell button type battery using a steel shell button type battery heat sealing mold provided by the present invention.

[0027] Included in the figure are:

[0028] 9-heat sealing mold, 11-positive electrode shell, 2-upper top mold, 12-negative electrode shell, 3-lower top mold, 4-sealing mold, 41-groove, 5-heating device, 42-first circular hole, 43-second circular hole, 421-annular boss, 422-first end face, 423-second end face, 13-sealing ring, 51-first terminal, 52-second terminal, 44-first chamfer, 45-first arc, 46-second chamfer, 47-third chamfer, 14-battery cell, 8-steel shell button battery. DETAILED DESCRIPTION

[0029] The technical scheme in this embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in this embodiment of the present invention. Obviously, the described embodiment is one embodiment of the present invention, not all embodiments of the present invention. Based on this embodiment of the present invention, all other embodiments of the present invention obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Example

[0030] Please refer to Figures 1 to 6 The first embodiment of the present invention provides a heat-sealing mold for a steel shell button battery. The heat-sealing mold 9 includes an upper mold 2 for sealing a positive electrode shell 11 and a lower mold 3 for sealing a negative electrode shell 12. The upper mold 2 is connected to a press. When working, the upper mold 2 moves downward, and the lower mold 3 does not move. A sealing mold 4 is installed between the upper mold 2 and the lower mold 3. The heat-sealing action of the steel shell button battery 8 is performed inside the sealing mold 4. Figure 3 As shown, a groove 41 is provided on the outside of the sealing mold 4, and a heating device 5 for heating the sealing mold 4 is installed inside the groove 41. The heating device 5 is controlled by a temperature controller module, and the temperature controller module controls the heating device 5 to reach the appropriate temperature required for heat sealing. A first circular hole 42 is provided at one end of the middle part of the sealing mold 4 for accommodating the up and down movement of the upper top mold 2, and a second circular hole 43 is provided at the other end for accommodating the up and down movement of the lower top mold 3. The upper top mold 2 moves up and down in the first circular hole 42, and the lower top mold 3 moves up and down in the second circular hole 43. Figure 5As shown, an annular boss 421 for pressing the end of the positive electrode shell 11 into an arc shape is provided at the end of the first circular hole 42, and the annular boss 421 includes a first end face 422 and a second end face 423, the diameter of the first end face 422 is larger than the diameter of the second end face 423, the annular boss 421 is larger at the upper end and smaller at the lower end, and the second end face 423 applies pressure to the sealing ring 13, and the annular boss 421 presses the end of the positive electrode shell 11 into an arc shape, and presses the end of the positive electrode shell 11 into the turning point of the negative electrode shell 12, and at the same time, the positive electrode shell 11 presses the sealing ring 13 to deform the sealing ring 13, and the positive electrode shell 11, the sealing ring 13 and the negative electrode shell 12 are connected together, which can improve the sealing performance of the steel shell button battery 8 and make the positive electrode shell 11 and the negative electrode shell 12 fit more tightly.

[0031] The groove 41 is in a spiral shape, and the heating device 5 is a spiral heating tube. The spiral heating tube can heat the sealing mold 4 more evenly, improve the heating efficiency, shorten the heating time, and prevent defective products caused by uneven heating. The heating device 5 is provided with a first terminal 51 and a second terminal 52. The first terminal 51 and the second terminal 52 are staggered with each other, and short circuit failure is not easy to occur.

[0032] The sealing mold 4 is provided with a first chamfer 44 around it, the upper end of the first circular hole 42 is provided with a first arc 45 for guiding the upper top mold 2, the lower end of the first circular arc 45 is provided with a second chamfer 46, and the lower end of the second circular hole 43 is provided with a third chamfer 47 for guiding the lower top mold 3. The first arc 45, the second chamfer 46 and the third chamfer 47 are beneficial to the up and down movement of the upper top mold 2 and the lower top mold 3, and are beneficial to rapid guiding.

[0033] The diameter of the upper top mold 2 is larger than that of the lower top mold 3, and the diameter of the first circular hole 42 is larger than that of the second circular hole 43. When the semi-finished steel shell button type battery 8 is placed in the sealing mold 4, it will not fall, and the semi-finished steel shell button type battery 8 can be stuck in the area of ​​the sealing mold 4 where sealing action is required, which is beneficial to the positioning of the semi-finished steel shell button type battery 8, saving production time and improving production efficiency.

[0034] The diameter of the second end surface 423 is smaller than the diameter of the second circular hole 43 , which is beneficial for the second end surface 423 to pressurize and shape the sealing ring 13 . Example

[0035] like Figure 7 As shown, the second embodiment of the present invention provides a method for manufacturing a steel shell button type battery by using a steel shell button type battery heat sealing mold, comprising the following steps:

[0036] Step S1, manufacturing the positive electrode housing 11 and the negative electrode housing 12; stamping a steel foil with a thickness of 2-3 mm using a production mold, so that the positive electrode housing 11 and the negative electrode housing 12 have grooves that are mutually compatible with the positive electrode sheet and the negative electrode sheet, and the openings have bent edges that can be engaged with each other;

[0037] Step S2, manufacturing positive electrode sheets and negative electrode sheets; coating the positive electrode slurry on the positive electrode collector, coating, shaping and drying, punching it into corresponding shapes with a punching machine to make positive electrode sheets, coating the negative electrode slurry on the negative electrode collector, coating, shaping and drying, punching it into corresponding shapes with a punching machine to make negative electrode sheets;

[0038] Step S3, welding the tabs to form a battery cell 14; welding the positive tabs on the positive electrode sheet, welding the negative tabs on the negative electrode sheet, and forming the battery cell 14 with the positive electrode sheet, the separator and the negative electrode sheet, and installing the sealing ring 13 between the positive electrode shell 11 and the negative electrode shell 12, welding all the positive tabs inside the battery cell 14 together and welded on the surface of the positive electrode shell 11, and welding all the negative tabs inside the battery cell 14 together and welded on the surface of the negative electrode shell 12, and installing the battery cell 14 into the grooves of the positive electrode shell 11 and the negative electrode shell 12;

[0039] Step S4, heat sealing is performed using a heat sealing mold 9; the positive electrode shell 11 and the negative electrode shell 12 are snap-fitted and fastened to form a battery shell, the above-mentioned battery shell is placed in the sealing mold 4, the heating device 5 is controlled to a suitable temperature by the temperature controller module, the press pushes the upper top mold 2 to move downward to extrude the positive electrode shell 11, and the heating device 5 heats the sealing ring 13. After the sealing ring 13 is heated and softened, it is extruded by the pressure of the heat sealing mold 9 to complement the wrinkles or cracks between the positive electrode shell 11 and the negative electrode shell 12. The sealing ring 13 fills the wrinkles or cracks between the positive electrode shell 11 and the negative electrode shell 12 to achieve gapless packaging, thereby more effectively improving the sealing effect of the battery, reducing the adverse phenomena caused by poor fusion of the sealing port, and improving the yield and production efficiency of the steel shell button battery 8.

[0040] In summary, the beneficial effects of the present invention are:

[0041] The end of the first circular hole 42 of the present invention is provided with an arc-shaped annular boss 421, which can press the end of the positive electrode shell 11 into an arc shape, press the end of the positive electrode shell 11 into the turning point of the negative electrode shell 12, and at the same time, the positive electrode shell 12 presses the sealing ring 13 to deform the sealing ring 13, and the positive electrode shell 11, the sealing ring 13 and the negative electrode shell 12 are connected together, which can improve the sealing performance of the steel shell button battery 8, so that the positive electrode shell 11 and the negative electrode shell 12 are more tightly buckled; the outer ring of the sealing mold 4 of the present invention is provided with a heating device 5, the heating device 5 heats the sealing ring 13, and after the sealing ring 13 is heated and softened, it is squeezed by the pressure of the heat sealing mold 9 to complement the wrinkles or cracks between the positive electrode shell 11 and the negative electrode shell 12, and the sealing ring 13 fills the wrinkles or cracks between the positive electrode shell 11 and the negative electrode shell 12 to achieve gapless packaging, thereby more effectively improving the sealing effect of the steel shell button battery 8, reducing the adverse phenomena caused by poor fusion of the sealing port, and improving the yield and production efficiency of the steel shell button battery 8.

Claims

1. A steel shell button battery heat sealing mold, characterized in that: The heat-sealing mold (9) comprises an upper mold (2) for sealing the positive electrode shell (11) and a lower mold (3) for sealing the negative electrode shell (12); a sealing mold (4) is arranged between the upper mold (2) and the lower mold (3); a groove (41) is arranged on the outside of the sealing mold (4); a heating device (5) for heating the sealing mold (4) is arranged inside the groove (41); a first groove (5) for accommodating the upper mold (2) to move up and down is arranged at one end of the middle part of the sealing mold (4); a circular hole (42), the other end of which is provided with a second circular hole (43) for accommodating the upper mold (3) to move up and down, the end of the first circular hole (42) is provided with an annular boss (421) for pressing the end of the positive electrode shell (11) into an arc shape, the annular boss (421) comprising a first end face (422) and a second end face (423), the diameter of the first end face (422) being greater than the diameter of the second end face (423), and the annular boss (421) being larger at the upper end and smaller at the lower end; The groove (41) is in a spiral shape, the heating device (5) is a spiral heating tube, and the heating device (5) is provided with a first terminal (51) and a second terminal (52).

2. A heat-sealing mold for steel shell button-type batteries according to claim 1, characterized in that: The heating device (5) is controlled by a temperature controller module.

3. A heat-sealing mold for steel shell button-type batteries according to claim 1, characterized in that: The sealing die (4) is provided with first chamfers (44) around its periphery, the first circular hole (42) is provided with a first circular arc (45) at the upper end thereof for guiding the upper die (2), the first circular arc (45) is provided with a second chamfer (46) at the lower end thereof, and the second circular hole (43) is provided with a third chamfer (47) at the lower end thereof for guiding the lower die (3).

4. A heat-sealing mold for steel shell button-type batteries according to claim 1, characterized in that: The diameter of the upper top mold (2) is greater than the diameter of the lower top mold (3), and the diameter of the first circular hole (42) is greater than the diameter of the second circular hole (43).

5. The heat-sealing mold for steel shell button type batteries according to claim 1, characterized in that: The diameter of the second end surface (423) is smaller than the diameter of the second circular hole (43).

6. A method for manufacturing a steel shell button type battery using a steel shell button type battery heat sealing mold as described in any one of claims 1 to 5, characterized in that: The following steps are involved: Step S1, manufacturing a positive electrode shell (11) and a negative electrode shell (12); using a production mold to stamp a steel foil with a thickness of 2-3 mm, so that the manufactured positive electrode shell (11) and the negative electrode shell (12) have grooves that are mutually compatible with the positive electrode sheet and the negative electrode sheet, and the openings have bent edges that can be mutually engaged; Step S2, manufacturing positive electrode sheets and negative electrode sheets; coating the positive electrode slurry on the positive electrode collector, coating, shaping and drying, punching it into corresponding shapes with a punching machine to make positive electrode sheets, coating the negative electrode slurry on the negative electrode collector, coating, shaping and drying, punching it into corresponding shapes with a punching machine to make negative electrode sheets; Step S3, welding the tabs to form a battery cell (14); welding the positive tabs on the positive electrode sheet, welding the negative tabs on the negative electrode sheet, combining the positive electrode sheet, the separator and the negative electrode sheet to form a battery cell (14), inserting a sealing ring (13) between the positive electrode shell (11) and the negative electrode shell (12), welding all the positive tabs inside the battery cell (14) together and welded to the surface of the positive electrode shell (11), welding all the negative tabs inside the battery cell (14) together and welded to the surface of the negative electrode shell (12), and inserting the battery cell (14) into the grooves of the positive electrode shell (11) and the negative electrode shell (12); Step S4, heat sealing is performed using a heat sealing mold (9); the positive electrode shell (11) and the negative electrode shell (12) are snap-fitted and fastened to form a battery shell, the battery shell is placed in a sealing mold (4), the heating device (5) is controlled to a suitable temperature by a temperature controller module, the press machine pushes the upper mold (2) to move downward to extrude the positive electrode shell (11), the heating device (5) heats the sealing ring (13), and after the sealing ring (13) is heated and softened, it is extruded by the pressure of the heat sealing mold (9) to complement the wrinkles or cracks between the positive electrode shell (11) and the negative electrode shell (12), and the sealing ring (13) fills the wrinkles or cracks between the positive electrode shell (11) and the negative electrode shell (12).

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