Welding mechanism for improving fracture of ceramic layer of positive plate of soft package battery

Abstract

The utility model belongs to the technical field of soft package battery manufacturing, and discloses a welding mechanism for improving the fracture of a ceramic layer of a positive plate of a soft package battery, which comprises a welding machine box body, one side of the welding machine box body is connected with a welding head and a welding seat, the welding head vertically slides above the welding seat, one side of the welding machine box body is provided with a welding carrier for pressing a battery cell, and the welding carrier is provided with a clamping groove for clamping the battery cell. The tab foil of the battery cell is pressed between the welding seat and the welding head; a movable plate is connected to the lower end of the welding machine box body, an electric cylinder is arranged on the other side of the welding machine box body, and a piston rod of the electric cylinder is connected with the movable plate and used for driving the welding machine box body on the movable plate to be close to or away from the welding carrier through the electric cylinder. Before welding, the electrode lug foil can be controlled to be bent, then the pressing state of the welding carrier on the battery cell is relieved, the welding head is axially pulled on the electrode lug foil in the welding process, the pulling force can be released, the situation that an anode ceramic layer and a material area are broken is avoided, and the electrode lug foil welding device is simple in structure and practical.

Description

Technical Field

[0001] The utility model belongs to the technical field of soft-pack battery manufacturing, and in particular relates to a welding mechanism for improving the fracture of a ceramic layer of a positive electrode sheet of a soft-pack battery. Background Art

[0002] Lithium-ion soft-pack batteries are widely used in the market because of their high energy density. The production demand is increasing day by day. However, the production and manufacturing difficulty and cost of lithium-ion soft-pack power batteries are also high. The structural properties of lithium-ion soft-pack batteries determine that some of its technical problems need to be improved and solved. As we all know, soft-pack batteries are mainly composed of positive electrode sheets, negative electrode sheets, diaphragms, electrolytes and aluminum-plastic film outer packaging. Due to safety design, the alignment of positive and negative electrode sheets and diaphragms will be controlled. The diaphragm size is required to be larger than the negative electrode size, and the negative electrode size is required to be larger than the positive electrode size. The diaphragm is larger than the negative electrode to ensure that the diaphragm can separate the positive and negative electrode sheets. The negative electrode size is larger than the positive electrode to ensure that the lithium ions released from the positive electrode have enough space to be embedded in the negative electrode, so as to ensure that there is no lithium precipitation, and no lithium dendrites are formed to pierce the diaphragm and form an internal short circuit. Since the safety risk of the negative electrode material area contacting the aluminum foil is the greatest, in order to avoid direct contact between the negative electrode material area and the aluminum foil, a ceramic layer is designed to be coated on the edge of the positive electrode sheet area. However, due to the design of the ceramic layer, there is an overlap between the ceramic layer and the positive electrode material area, about 0-1mm, and the ceramic layer is on top and the positive electrode material area is on the bottom. As a result, the positive electrode sheet can be divided into three parts, including the positive electrode material area, the overlapping part of the ceramic layer and the material area, and the ceramic layer area. The junction between the ceramic and the material area is the dividing point for the extension of the foil (after rolling when the material area is thick, the foil is extended; when the ceramic area is thin, the foil has very little extension); when the tab is subjected to force, the ceramic area can disperse the internal stress through the ceramic layer, and the material area can disperse the internal stress through the black material. However, due to the mutual dissolution of ceramic and black material at the junction, it is an independent stress dispersion area, and the stress is concentrated in the area. During the welding process, the battery cell will be loaded into the welding turntable through the welding carrier for pre-welding, tab cutting, and final welding.

[0003] In the prior art, after the welding turntable carries the battery cell to the pre-welding or final welding station, the pressure block on the core package carrier presses the carrier, the welding head descends, and the pole tab foil is pressed between the welding head and the welding seat. Then the welding head performs axial movement welding on the pole tab foil. After the welding is completed, the welding head rises, the pressure block on the carrier is lifted, and the carrier rotates to the next station. During welding, due to the axial movement of the welding head ultrasonic welding, a pulling force will be generated on the foil. At the same time, because the pole piece is pressed and restrained, the stress cannot be released when it is pulled, and the positive electrode ceramic layer and the material area are prone to breakage. Therefore, it is necessary to improve the prior art. Utility Model Content

[0004] The utility model aims to provide a welding mechanism for improving the fracture of the ceramic layer of the positive electrode sheet of a soft-pack battery, so as to solve the above-mentioned problems existing in the prior art.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] A welding mechanism for improving the fracture of a ceramic layer of a positive electrode sheet of a soft-pack battery comprises a welding machine housing, a welding head and a welding seat are connected to one side of the welding machine housing, the welding head slides vertically above the welding seat, a welding carrier for pressing a battery cell is arranged on one side of the welding machine housing, and the tab foil of the battery cell is pressed between the welding seat and the welding head; a movable plate is connected to the lower end of the welding machine housing, an electric cylinder is arranged on the other side of the welding machine housing, and a piston rod of the electric cylinder is connected to the movable plate, so as to drive the welding machine housing on the movable plate to approach or move away from the welding carrier through the electric cylinder.

[0007] As a preferred technical solution in the present invention, the welding carrier includes a fixed welding carrier lower pressure plate and a welding carrier upper pressure plate elastically connected above the welding carrier lower pressure plate, and the battery cell is pressed tightly between the welding carrier lower pressure plate and the welding carrier upper pressure plate.

[0008] As a preferred technical solution in the present invention, at least two vertical limit rods are fixedly connected to the lower pressure plate of the welding carrier, the upper part of the vertical limit rod passes through the upper pressure plate of the welding carrier, and an annular limit plate is provided at the upper end of the vertical limit rod, and a downward pressure spring is sleeved on the vertical limit rod between the annular limit plate and the upper pressure plate of the welding carrier.

[0009] As a preferred technical solution in the utility model, a lifting mechanism is arranged below the lower pressure plate of the welding carrier, at least two lifting rods are arranged on the lifting mechanism, and the lifting rods of the lifting mechanism pass through the lower pressure plate of the welding carrier and are connected to the upper pressure plate of the welding carrier.

[0010] As a preferred technical solution in the utility model, a positioning seat is provided at the lower end of the lower pressure plate of the welding carrier, and the lower pressure plate of the welding carrier is fixed on the positioning seat; an installation groove is opened in the middle of the positioning seat, the jacking mechanism is installed in the installation groove, and the jacking mechanism The jacking rod passes through the upper end of the positioning seat.

[0011] As a preferred technical solution in the utility model, the welding mechanism also includes an operating table, the positioning seat and the electric cylinder are fixed on the operating table, a slide rail is arranged on the operating table, and the movable plate is slidably connected to the slide rail.

[0012] Beneficial effects: The utility model can realize the compression and release of the battery cell through the welding carrier, and then install the welding machine box on the movable plate driven by the electric cylinder. Before welding, the welding head first descends to a fixed height and clamps the pole tab foil with the welding seat. These three parts are moved a certain distance toward the battery cell through the combined action of the movable plate and the electric cylinder, so that the pole tab foil is bent, and then the compression state of the welding carrier on the battery cell is released. When welding, the welding head performs axial pulling on the pole tab foil. The bent pole tab foil and the unconstrained battery cell can leave a buffer space, so that the pulling force can be released, avoiding the breakage of the positive electrode ceramic layer and the material area. The structure is simple and practical. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a structural schematic diagram of the utility model;

[0014] Figure 2 It is a partial structural schematic diagram of the utility model.

[0015] In the figure: 1-welding head; 2-welding seat; 3-electric cylinder; 4-movable plate; 5-welding carrier; 501-upper pressure plate of welding carrier; 502-lower pressure plate of welding carrier; 503-vertical limit rod; 504-annular limit plate; 505-down pressure spring; 6-battery cell; 7-lifting mechanism; 8-welding machine chassis; 9-ear foil; 10-lifting rod; 11-positioning seat; 12-operating table. DETAILED DESCRIPTION

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the utility model or the prior art, the utility model will be briefly introduced below in combination with the drawings and the description of the embodiments or the prior art. Obviously, the following description of the structure of the drawings is only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. It should be noted that the description of these embodiments is used to help understand the utility model, but does not constitute a limitation of the utility model.

[0017] Example:

[0018] like Figure 1 and Figure 2As shown, this embodiment provides a welding mechanism for improving the fracture of the ceramic layer of the positive electrode sheet of a soft-pack battery, including a welding machine housing 8, one side of the welding machine housing 8 is connected to a welding head 1 and a welding seat 2, the welding head 1 slides vertically above the welding seat 2, and one side of the welding machine housing 8 is provided with a welding carrier 5 for pressing the battery cell 6 to ensure the stability of the battery cell 6, and the tab foil material 9 of the battery cell 6 is pressed between the welding seat 2 and the welding head 1; the lower end of the welding machine housing 8 is connected to a movable plate 4, and the other side of the welding machine housing 8 is provided with an electric cylinder 3, and the piston rod of the electric cylinder 3 is connected to the movable plate 4, so as to drive the movable plate 4 through the electric cylinder 3. The welding machine case 8 on the plate 4 is close to or away from the welding carrier 5. Before welding, the welding head 1 first descends to a fixed height (contacting the tab foil 9) and clamps the tab foil 9 with the welding seat 2. These three parts are moved a certain distance toward the battery cell 6 through the combined action of the movable plate 4 and the electric cylinder 3, so that the tab foil 9 is bent, and then the pressing state of the welding carrier 5 on the battery cell 6 is released. When welding, the welding head 1 performs axial pulling on the tab foil 9. The bent tab foil 9 and the unconstrained battery cell 6 can leave a buffer space, so that the pulling force can be released, thereby avoiding the breakage of the positive electrode ceramic layer and the material area.

[0019] The utility model can realize the pressing and releasing of the battery cell 6 through the welding carrier 5, and then install the welding machine case 8 on the movable plate 4 driven by the electric cylinder 3. Before welding, the welding head 1 is first lowered to a fixed height and clamps the pole tab foil 9 with the welding seat 2. These three parts are moved a certain distance toward the battery cell 6 through the combined action of the movable plate 4 and the electric cylinder 3, so that the pole tab foil 9 is bent, and then the pressing state of the welding carrier 5 on the battery cell 6 is released. When welding, the welding head 1 performs axial pulling on the pole tab foil 9, and the bent pole tab foil 9 and the unconstrained battery cell 6 can leave a buffer space, so that the pulling force can be released, thereby avoiding the breakage of the positive electrode ceramic layer and the material area. The structure is simple and practical.

[0020] As a preferred implementation scheme in this embodiment, it needs to be further explained that the welding carrier 5 includes a fixedly arranged welding carrier lower pressure plate 502 and a welding carrier upper pressure plate 501 elastically connected to the upper part of the welding carrier lower pressure plate 502. The battery cell 6 is pressed between the welding carrier lower pressure plate 502 and the welding carrier upper pressure plate 501. In a natural state, the welding carrier upper pressure plate 501 can cooperate with the welding carrier lower pressure plate 502 to press the battery cell 6. When the pressing state of the battery cell 6 needs to be released, it is only necessary to lift the welding carrier upper pressure plate 501.

[0021] As a preferred implementation scheme in this embodiment, it needs to be further explained that at least two vertical limit rods 503 are fixedly connected to the lower pressure plate 502 of the welding carrier, and the upper part of the vertical limit rod 503 passes through the upper pressure plate 501 of the welding carrier, and the upper end of the vertical limit rod 503 is provided with an annular limit plate 504, and the vertical limit rod 503 between the annular limit plate 504 and the upper pressure plate 501 of the welding carrier is sleeved with a downward pressure spring 505. By utilizing the elastic force of the downward pressure spring 505, the upper pressure plate 501 of the welding carrier can cooperate with the lower pressure plate 502 of the welding carrier to press the battery cell 6 in a natural state, and the structure is simple and practical.

[0022] As a preferred implementation scheme in this embodiment, it needs to be further explained that a lifting mechanism 7 is arranged below the lower pressure plate 502 of the welding carrier, and at least two push rods 10 are arranged on the lifting mechanism 7. The lifting mechanism 7 provided with the push rods 10 can be understood as an electric cylinder, a pneumatic cylinder or a telescopic rod, and the push rod 10 of the lifting mechanism 7 passes through the lower pressure plate 502 of the welding carrier and is connected to the upper pressure plate 501 of the welding carrier. When it is necessary to lift the upper pressure plate 501 of the welding carrier, it is only necessary to control the lifting mechanism 7 to move the push rod 10 upward, which is simple and practical to operate.

[0023] As a preferred implementation scheme in this embodiment, it needs to be further explained that a positioning seat 11 is provided at the lower end of the welding carrier lower pressure plate 502, and the welding carrier lower pressure plate 502 is fixed on the positioning seat 11, which can ensure the stability of the welding carrier lower pressure plate 502; a mounting groove is opened in the middle of the positioning seat 11, and the jacking mechanism 7 is installed in the mounting groove, and the jacking rod 10 of the jacking mechanism 7 passes through the upper end of the positioning seat 11, which can ensure the stability of the jacking mechanism 7, and also can ensure the relative position relationship between the jacking mechanism 7 and the welding carrier lower pressure plate 502.

[0024] As a preferred implementation scheme in this embodiment, it needs to be further explained that the welding mechanism also includes an operating table 12, the positioning seat 11 and the electric cylinder 3 are both fixed on the operating table 12, a slide rail is provided on the operating table 12, and the movable plate 4 is slidably connected to the slide rail to realize the integrated design of the overall equipment.

[0025] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A welding mechanism for improving the fracture of the ceramic layer of the positive electrode sheet of a soft-pack battery, comprising a welding machine housing (8), a welding head (1) and a welding seat (2) connected to one side of the welding machine housing (8), the welding head (1) vertically sliding above the welding seat (2), characterized in that: A welding carrier (5) for pressing the battery cell (6) is arranged on one side of the welding machine housing (8), and the tab foil (9) of the battery cell (6) is pressed between the welding seat (2) and the welding head (1); a movable plate (4) is connected to the lower end of the welding machine housing (8), and an electric cylinder (3) is arranged on the other side of the welding machine housing (8), and a piston rod of the electric cylinder (3) is connected to the movable plate (4) so ​​as to drive the welding machine housing (8) on the movable plate (4) to approach or move away from the welding carrier (5) through the electric cylinder (3).

2. A welding mechanism for improving the fracture of the ceramic layer of the positive electrode sheet of a soft-pack battery according to claim 1, characterized in that: The welding carrier (5) comprises a fixedly arranged welding carrier lower pressing plate (502) and a welding carrier upper pressing plate (501) elastically connected above the welding carrier lower pressing plate (502), and the battery cell (6) is pressed tightly between the welding carrier lower pressing plate (502) and the welding carrier upper pressing plate (501).

3. A welding mechanism for improving the fracture of the ceramic layer of the positive electrode sheet of a soft-pack battery according to claim 2, characterized in that: At least two vertical limiting rods (503) are fixedly connected to the lower pressing plate (502) of the welding carrier, the upper part of the vertical limiting rod (503) passes through the upper pressing plate (501) of the welding carrier, and an annular limiting plate (504) is arranged at the upper end of the vertical limiting rod (503), and a downward pressing spring (505) is sleeved on the vertical limiting rod (503) between the annular limiting plate (504) and the upper pressing plate (501) of the welding carrier.

4. A welding mechanism for improving the fracture of the ceramic layer of the positive electrode sheet of a soft-pack battery according to claim 2 or 3, characterized in that: A lifting mechanism (7) is provided below the lower pressing plate (502) of the welding carrier, and at least two lifting rods (10) are provided on the lifting mechanism (7). The lifting rods (10) of the lifting mechanism (7) penetrate the lower pressing plate (502) of the welding carrier and are connected to the upper pressing plate (501) of the welding carrier.

5. A welding mechanism for improving the fracture of the ceramic layer of the positive electrode sheet of a soft-pack battery according to claim 4, characterized in that: A positioning seat (11) is provided at the lower end of the welding carrier lower pressure plate (502), and the welding carrier lower pressure plate (502) is fixed on the positioning seat (11); a mounting groove is provided in the middle of the positioning seat (11), and the jacking mechanism (7) is installed in the mounting groove, and the jacking rod (10) of the jacking mechanism (7) passes through the upper end of the positioning seat (11).

6. A welding mechanism for improving the fracture of the ceramic layer of the positive electrode sheet of a soft-pack battery according to claim 5, characterized in that: The welding mechanism also includes an operating table (12), the positioning seat (11) and the electric cylinder (3) are both fixed on the operating table (12), a slide rail is arranged on the operating table (12), and the movable plate (4) is slidably connected to the slide rail.

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