Preparation process of high-performance supercapacitor

Abstract

A manufacturing process for a high-performance supercapacitor includes a shell with an internally formed mounting cavity, a cell disposed within the mounting cavity, a positive current collector laser-welded to the bottom of the cell, a negative current collector laser-welded to the top of the cell, a top cover disposed on the upper end of the shell for sealing the mounting cavity, a positive electrode post disposed on one side of the top surface of the top cover, a negative electrode post assembly disposed on the other side of the top surface of the top cover and connected to the negative current collector, a positioning post extending upward from the bottom of the mounting cavity, an injection hole extending upward from the bottom of the shell through the positioning post, and a sealing rubber plug assembly for sealing the injection hole. The cell forms an injection channel extending upward from its bottom for the positioning post to be embedded. The injection hole and the sealing rubber plug assembly sealing the injection hole are disposed at the bottom of the shell. Through the cooperation between the two, the waste gas and electrolyte after the high-temperature aging during the first charge and discharge are replaced, reducing the internal gas pressure of the supercapacitor while improving the capacitor's performance and service life.

Description

Technical Field

[0001] This invention belongs to the field of supercapacitor fabrication, specifically relating to a fabrication process for a high-performance supercapacitor. Background Technology

[0002] Supercapacitors, as an emerging advanced energy storage device, combine the high power characteristics of traditional capacitors with the high energy characteristics of batteries. Due to their unique high specific power, high current discharge capability, ultra-low temperature characteristics, high reliability, and environmental friendliness, they are widely used and developed in numerous fields such as power, transportation, communications, energy, and aerospace.

[0003] Existing supercapacitors use conductive foil or sheet-like leads to connect the cell to the top cover. Due to the limited contact area, it is difficult to achieve an ideal state when manufacturing low-internal-resistance supercapacitors. Furthermore, the cell, pulled by the leads, is in a non-rigid, suspended state within the casing, thus affecting the capacitor's durability and vibration resistance. Secondly, existing supercapacitors use sealing rubber rings as the seal between the top cover and the outer casing. The positive terminal of the cell is rigidly fixed, and the impact vibration stress is applied to the metal current collector and the outer casing. However, the negative terminal's impact vibration stress point is the sealing rubber ring. When the capacitor is subjected to a force perpendicular to its body, the negative terminal... Non-rigid fixing will affect the rigid fixing connection at the positive end, which is prone to damage. At the same time, the sealing rubber ring will accelerate the failure of permanent deformation rate under long-term stress impact, reducing sealing performance. Finally, after the existing supercapacitors are injected with liquid and assembled, they need to undergo high-temperature aging treatment to eliminate potential defects and improve the reliability and stability of the capacitor. During the first charge and discharge and high-temperature aging, a large amount of impurities such as moisture decomposes, producing a series of chemical side reactions, generating new impurity liquids and gases, which increases the internal gas pressure of the capacitor. These impurity liquids and gases will continue to affect the degradation of the capacitor's electrical performance during subsequent use. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a manufacturing process for high-performance supercapacitors.

[0005] The present invention adopts the following technical solution:

[0006] A manufacturing process for a high-performance supercapacitor, the supercapacitor comprising a shell with an internally formed mounting cavity, a cell disposed in the mounting cavity, a positive current collector laser-welded to the bottom of the cell, a negative current collector laser-welded to the top of the cell, a top cover disposed on the upper end of the shell for sealing the mounting cavity, a positive electrode post disposed on one side of the top surface of the top cover, a negative electrode post assembly disposed on the other side of the top surface of the top cover and connected to the negative current collector, a positioning post extending upward from the bottom of the mounting cavity, an injection hole extending upward from the bottom of the shell through the positioning post, and a sealing rubber plug assembly for sealing the injection hole, wherein the cell forms an injection channel extending upward from its bottom for the positioning post to be embedded, and the injection hole communicates with the injection channel;

[0007] The preparation process specifically includes the following steps:

[0008] Step 1: Laser weld the positive current collector and the negative current collector to the upper and lower ends of the battery cell respectively. Then install the battery cell in the mounting cavity, so that the positioning post is embedded in the liquid injection channel, and the liquid injection hole is connected to the liquid injection channel.

[0009] Step 2: Fix the negative terminal assembly onto the top cover, then connect the top cover to the upper end of the outer shell to seal the mounting cavity and form a semi-finished capacitor;

[0010] Step 3: Transfer the semi-finished capacitor to the oven to dry the cells inside the shell, and then inject the electrolyte into the injection channel through the injection hole to fully wet the cells.

[0011] Step 4: Seal the injection hole with a sealing rubber plug assembly, and then transfer it to the aging chamber for aging treatment;

[0012] Step 5: Transfer the semi-finished capacitor after aging treatment out of the aging chamber, remove the sealing rubber plug assembly, then extract the electrolyte and exhaust gas from the installation cavity through the injection hole, re-inject the electrolyte, and finally reinstall the sealing rubber plug assembly to seal the injection hole to obtain the supercapacitor.

[0013] Furthermore, the sealing rubber plug assembly includes a rubber plug that is sealed and fixed in the injection hole and a metal plug for fixing the rubber plug, wherein the metal plug and the injection hole are connected by threads.

[0014] Furthermore, the metal plug includes a metal plug body embedded in the injection hole at the lower end of the rubber plug and a limiting block disposed on the outer periphery of the metal plug body and in contact with the bottom of the outer shell. The bottom of the outer shell has a limiting groove for the limiting block to be embedded. In step 5, after the electrolyte is re-injected, the limiting block and the limiting groove are sealed and welded together using laser welding.

[0015] Furthermore, in step 4, the aging temperature is 60-70℃ and the aging time is 5-7 hours.

[0016] Furthermore, the negative electrode assembly includes a negative electrode cover connected to a mounting hole, a negative electrode post extending downward from the negative electrode cover and welded to the negative current collector, and a sealing element disposed between the negative electrode post and the upper cover and the negative electrode cover. The upper cover is provided with a mounting hole for installing the negative electrode post.

[0017] Furthermore, it also includes an adapter piece that is laser-welded to the lower end of the negative electrode post on the negative current collector, and the adapter piece is provided with a welding hole for the lower end of the negative electrode post to be inserted.

[0018] Furthermore, the sealing element is fitted onto the washer located in the negative electrode cover on the negative electrode post, and a rubber sealing ring is disposed at the lower end of the washer between the negative electrode cover and the upper cover.

[0019] Furthermore, the rubber sealing ring is arranged in an I-shape, including two horizontal segments that are opposite each other and a vertical segment connecting the two horizontal segments; the diameter of the horizontal segment is larger than the diameter of the washer, and the negative electrode cover is formed with a stepped groove extending upward from its bottom for the washer to be embedded in the upper horizontal segment.

[0020] Furthermore, the negative terminal includes a negative terminal located at the upper end of the negative terminal cover, an extension section extending downward from the bottom of the negative terminal for installing a seal, and a connecting section disposed at the lower end of the extension section and connected to the negative current collector. A limiting ring is formed on the outer periphery of the upper end of the extension section to restrict the installation position of the seal.

[0021] Furthermore, the mounting hole and the negative electrode cover are connected by threads.

[0022] As can be seen from the above description of the present invention, compared with the prior art, the beneficial effects of the present invention are as follows: By defining the structural composition of the capacitor, the present application extensively uses laser welding to seal between components, reduces the area of ​​rubber used in the seal, forms a high-sealing structure and reduces internal resistance, and simultaneously defines the structural composition of the negative electrode post as a new stress support point, avoiding the need for the rubber sealing ring to withstand physical stress impact while serving as a sealing element, thereby improving the capacitor's vibration resistance and sealing performance; in addition, by providing an injection hole and a sealing rubber plug assembly for sealing the injection hole at the bottom of the outer shell, the exhaust gas and electrolyte after the high-temperature aging of the first charge and discharge are replaced through the cooperation between the two, reducing the internal gas pressure of the supercapacitor while also improving the capacitor's performance and service life. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of a supercapacitor structure;

[0024] Figure 2 This is an exploded view of the supercapacitor structure.

[0025] Figure 3 This is a partial structural cross-sectional view of a supercapacitor;

[0026] Figure 4 for Figure 3 Enlarged view of the middle section structure;

[0027] Figure 5 This is a partial structural cross-sectional view of the negative electrode cover;

[0028] Figure 6 Schematic diagram of the negative electrode post Figure 1 ;

[0029] Figure 7 Schematic diagram of the negative electrode post Figure 2 ;

[0030] Figure 8 This is a partial structural cross-sectional view of the metal plug;

[0031] In the diagram, 11-outer shell, 12-cell, 13-positive current collector, 14-negative current collector, 15-top cover, 16-positive terminal, 17-negative terminal assembly, 18-adapter plate, 19-positioning post, 20-filling hole, 21-sealing rubber plug assembly, 111-mounting cavity, 112-limiting groove, 121-filling channel, 131-slot, 141-annular boss, 151-mounting hole, 171-negative cover, 1711- Stress hole, 1712-step groove, 172-negative pole, 1721-negative pole terminal, 1722-extension section, 1723-connecting section, 1724-limiting ring, 173-seal, 1731-washer, 1732-rubber sealing ring, 1733-horizontal section, 1734-vertical section, 181-welding hole, 211-rubber plug, 212-metal plug, 2121-metal plug body, 2122-limiting block. Detailed Implementation

[0032] The present invention will be further described below through specific embodiments.

[0033] Reference Figures 1 to 8 As shown, a high-performance supercapacitor includes a housing 11 with an internally formed mounting cavity 111, a cell 12 disposed in the mounting cavity 111, a positive current collector 13 laser-welded to the bottom of the cell 12, a negative current collector 14 laser-welded to the top of the cell 12, a top cover 15 disposed on the upper end of the housing 11 for sealing the mounting cavity 111, a positive electrode post 16 disposed on one side of the top surface of the top cover 15, a negative electrode post assembly 17 disposed on the other side of the top surface of the top cover 15 and connected to the negative current collector 14, an adapter piece 18 laser-welded to the negative current collector 25 and laser-welded to the lower end of the negative electrode post assembly 17, a positioning post 19 extending upward from the bottom of the mounting cavity 111, an injection hole 20 extending upward from the bottom of the housing 11 through the positioning post 19, and a sealing rubber plug assembly 21 for sealing the injection hole 20.

[0034] The battery cell 12 is formed by stacking and winding a negative electrode sheet, an inner diaphragm, a positive electrode sheet and an outer diaphragm in sequence. It has an injection channel 121 that extends upward from the top of the cell for the positioning post 19 to be embedded. The injection hole 20 is connected to the injection channel 121.

[0035] The positive current collector 13 forms a slot 131 into which the lower end of the power supply core 12 is inserted, so that the upper end of the positive current collector 13 wraps around the outer periphery of the lower end of the power supply core 12 to improve the vibration resistance of the power supply core 12. At the same time, it is interference-fitted with the mounting cavity 11. After installation, the inner wall of the mounting cavity 11 is sealed to the positive current collector 13 by through soldering.

[0036] The negative current collector 14 has an upwardly extending annular boss 141, and the inner diameter of the boss 141 is the same as the outer diameter of the adapter piece 18. After the adapter piece 18 is installed on the negative current collector 14, the two are welded together along the edge by laser welding. This method replaces the conventional use of lead bars as adapters, which improves the vibration resistance, reduces the contact resistance, and improves the high current discharge capability of the capacitor.

[0037] The top cover 15 is made of aluminum and has the same surface diameter as the inner diameter of the outer shell 11. The reverse edge is chamfered for easy installation. The top cover 15 is provided with mounting holes 151 for installing the negative terminal assembly 17. Specifically, the positive terminal 16 is integrally formed with the top cover 15.

[0038] The negative electrode assembly 17 includes a negative electrode cover 171 connected to the mounting hole 151, a negative electrode post 172 extending downward from the negative electrode cover 171 and laser-welded to the adapter piece 18, and a sealing member 173 disposed between the upper cover 15 and the negative electrode cover 171. The negative electrode cover 171 is threadedly connected to the mounting hole 151, and its surface is provided with stress holes 1711 to facilitate stress application. Specifically, the negative electrode cover 171 is made of a special ceramic or resin material that is insulating and has high strength.

[0039] The negative terminal 172 includes a negative terminal 1721 located at the upper end of the negative terminal cover 171, an extension section 1722 extending downward from the bottom of the negative terminal 1721 for mounting a seal 173, and a connecting section 1723 disposed at the lower end of the extension section 1722 and connected to the negative current collector 14. The upper outer periphery of the extension section 1722 is formed with a limiting ring 1724 to restrict the installation position of the seal 173. Specifically, the adapter piece 18 is provided with a welding hole 181 for the lower end of the connecting section 1723 to be inserted.

[0040] The sealing element 173 includes a washer 1731 fitted onto the negative electrode post 172 and located in the negative electrode cover 171, and a rubber sealing ring 1732 disposed at the lower end of the washer 1731 between the negative electrode cover 171 and the upper cover 15. Specifically, the rubber sealing ring 1732 is I-shaped and includes two horizontal sections 1733 opposite each other and a vertical section 1734 connecting the two horizontal sections 1733. The vertical section 1734 fits against the inner wall of the mounting hole 151. The diameter of the horizontal section 1733 is larger than the diameter of the washer 1731, and the diameter of the washer 1731 is larger than the diameter of the limiting ring 1724. The negative electrode cover 171 has a stepped groove 1712 extending upward from its bottom for the washer 1731, the upper horizontal section, and the limiting ring 1724 to be embedded.

[0041] The sealing rubber plug assembly 21 includes a rubber plug 211 that is sealed and fixed in the injection hole 20 and a metal plug 212 for fixing the rubber plug 211. Specifically, the metal plug 212 is threadedly connected to the injection hole 20. It includes a metal plug body 2121 that can be embedded in the injection hole 20 and located at the lower end of the rubber plug 211, and a limiting block 2122 that is disposed on the outer periphery of the metal plug body 2121 and contacts and connects with the bottom of the outer shell 11. The bottom of the outer shell 11 has a limiting groove 112 for the limiting block 2122 to be embedded.

[0042] Its preparation process specifically includes the following steps:

[0043] Step 1: Laser weld the positive current collector 13 and the negative current collector 14 to the upper and lower ends of the battery cell 12 respectively. Then install the battery cell 12 in the mounting cavity 111, so that the positioning post 19 is embedded in the liquid injection channel 121 and the liquid injection hole 20 is connected to the liquid injection channel 121.

[0044] Step 2: Fix the negative terminal assembly 17 onto the upper cover 15, then connect the upper cover 15 to the upper end of the outer shell 11 to seal the mounting cavity 111 and form a semi-finished capacitor.

[0045] Step 3: Transfer the semi-finished capacitor to the oven to dry the cell 12 inside the shell. Then, inject the electrolyte into the injection channel 121 through the injection hole 20 to fully wet the cell 12.

[0046] Step 4: Seal the injection hole 20 with the sealing rubber plug assembly 21, and then transfer it to the aging chamber at 60-70℃ for aging treatment for 5-7 hours.

[0047] Step 5: Transfer the semi-finished capacitor after aging treatment out of the aging chamber, remove the sealing rubber plug assembly 21, then extract the electrolyte and exhaust gas from the mounting cavity 111 through the injection hole 20, and then re-inject the electrolyte. Finally, reinstall the sealing rubber plug assembly 21, and use laser welding to connect the limiting block 2122 of the metal plug 212 to the limiting groove 112 to seal the injection hole 20, so as to obtain a high-performance supercapacitor.

[0048] This application defines the structural composition of the capacitor, extensively uses laser welding to seal between components, reduces the area of ​​rubber used in the seal, forms a high-sealing structure and reduces internal resistance. At the same time, it defines the structural composition of the negative electrode post 172 as a new stress support point, avoiding the need for the rubber sealing ring 1732 to withstand physical stress impact while serving as a sealing element, thereby improving the capacitor's vibration resistance and sealing performance. In addition, a liquid injection hole 20 and a sealing rubber plug assembly 21 for sealing the liquid injection hole are provided at the bottom of the outer shell 11. Through the cooperation between the two, the exhaust gas and electrolyte after the high-temperature aging during the first charge and discharge are replaced, reducing the internal gas pressure of the supercapacitor and improving the capacitor's performance and service life.

[0049] The above description is merely a preferred embodiment of the present invention and should not be construed as limiting the scope of the present invention. All equivalent changes and modifications made in accordance with the scope of the patent application and the contents of the specification of the present invention should still fall within the scope of the patent of the present invention.

Claims

1. A method for fabricating a high-performance supercapacitor, characterized in that: The supercapacitor includes a shell with an internally formed mounting cavity, a cell disposed in the mounting cavity, a positive current collector laser-welded to the bottom of the cell, a negative current collector laser-welded to the top of the cell, a top cover disposed on the upper end of the shell for sealing the mounting cavity, a positive electrode post disposed on one side of the top surface of the top cover, a negative electrode post assembly disposed on the other side of the top surface of the top cover and connected to the negative current collector, a positioning post extending upward from the bottom of the mounting cavity, an injection hole extending upward from the bottom of the shell through the positioning post, and a sealing rubber plug assembly for sealing the injection hole. The cell forms an injection channel extending upward from its bottom for the positioning post to be embedded in, and the injection hole communicates with the injection channel. The preparation method specifically includes the following steps: Step 1: Laser weld the positive current collector and the negative current collector to the upper and lower ends of the battery cell respectively. Then install the battery cell in the mounting cavity, so that the positioning post is embedded in the liquid injection channel, and the liquid injection hole is connected to the liquid injection channel. Step 2: Fix the negative terminal assembly onto the top cover, then connect the top cover to the upper end of the outer shell to seal the mounting cavity and form a semi-finished capacitor; Step 3: Transfer the semi-finished capacitor to the oven to dry the cells inside the shell, and then inject the electrolyte into the injection channel through the injection hole to fully wet the cells. Step 4: Seal the injection hole with a sealing rubber plug assembly, and then transfer it to the aging chamber for aging treatment; Step 5: Transfer the semi-finished capacitor after aging treatment out of the aging chamber, remove the sealing rubber plug assembly, then extract the electrolyte and exhaust gas in the installation cavity through the injection hole, then re-inject the electrolyte, and finally reinstall the sealing rubber plug assembly to seal the injection hole to obtain the supercapacitor. The sealing rubber plug assembly includes a rubber plug that is sealed and fixed in the injection hole and a metal plug for fixing the rubber plug. The metal plug is threadedly connected to the injection hole.

2. The method for preparing a high-performance supercapacitor according to claim 1, characterized in that: The metal plug includes a metal plug body embedded in the injection hole at the lower end of the rubber plug and a limiting block disposed on the outer periphery of the metal plug body and in contact with the bottom of the outer shell. The bottom of the outer shell has a limiting groove for the limiting block to be embedded. In step 5, after the electrolyte is re-injected, the limiting block and the limiting groove are sealed and welded together using laser welding.

3. The method for preparing a high-performance supercapacitor according to claim 1, characterized in that: In step 4, the aging temperature is 60-70℃ and the aging time is 5-7 hours.

4. The method for preparing a high-performance supercapacitor according to claim 1, characterized in that: The negative electrode assembly includes a negative electrode cover connected to a mounting hole, a negative electrode post extending downward from the negative electrode cover and welded to a negative current collector, and a sealing element disposed between the negative electrode post and the upper cover and the negative electrode cover. The upper cover is provided with a mounting hole for installing the negative electrode post.

5. The method for preparing a high-performance supercapacitor according to claim 4, characterized in that: It also includes an adapter piece that is laser-welded to the lower end of the negative electrode post on the negative current collector, and the adapter piece is provided with a welding hole for the lower end of the negative electrode post to be inserted.

6. The method for preparing a high-performance supercapacitor according to claim 4, characterized in that: The sealing element consists of a washer fitted on the negative electrode post and located inside the negative electrode cover, and a rubber sealing ring located at the lower end of the washer between the negative electrode cover and the upper cover.

7. The method for preparing a high-performance supercapacitor according to claim 6, characterized in that: The rubber sealing ring is arranged in an I-shape, including two horizontal sections that are opposite each other and a vertical section connecting the two horizontal sections; the diameter of the horizontal section is larger than the diameter of the washer, and the negative electrode cover is formed with a stepped groove extending upward from its bottom for the washer to be embedded in the upper horizontal section.

8. The method for preparing a high-performance supercapacitor according to claim 4, characterized in that: The negative terminal includes a negative terminal located at the upper end of the negative terminal cover, an extension section extending downward from the bottom of the negative terminal for installing a seal, and a connecting section located at the lower end of the extension section and connected to the negative current collector. A limiting ring is formed on the outer periphery of the upper end of the extension section to restrict the installation position of the seal.

9. The method for preparing a high-performance supercapacitor according to claim 4, characterized in that: The mounting hole and the negative electrode cover are connected by threads.

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