Double-electric-layer button type supercapacitor and production line

Abstract

The invention relates to the technical field of capacitors, in particular to a double-electrode-layer button type super capacitor and a production line, the double-electrode-layer button type super capacitor at least comprises a positive plate, a negative plate, an electrolyte system, a shell, a diaphragm and pins, the novel electrolyte system of tetrafluoroborate bis-spiro quaternary ammonium salt (SBP-BF4), sulfolane and dimethyl sulfone is adopted, and the working voltage reaches 3.3 V. Meanwhile, the first full-automatic positive and negative electrode pasting, assembling and sealing production line with the diameter of 6 mm in China is designed, and high-precision automatic production is achieved through the video recognition and segmented pressure control technology. The button type supercapacitor can fill the blank of domestic high-end button type supercapacitors, is widely applied to the fields of solar watches, automobile data recorders and the like, and has remarkable economic and social benefits.

Description

Technical Field

[0001] This invention relates to the field of capacitor technology, and more particularly to a double-layer button supercapacitor; it also relates to a double-layer button supercapacitor production line. Background Technology

[0002] Supercapacitors, as a novel energy storage device situated between traditional capacitors and rechargeable batteries, have attracted significant attention due to their large capacity, high energy density, wide operating temperature range, and extremely long lifespan. Compared to batteries, supercapacitors offer higher specific power and are environmentally friendly, thus finding widespread application in instrumentation, clock backup power, and other scenarios requiring efficient and environmentally friendly energy storage. Button-type supercapacitors, as an important structural form of supercapacitors, occupy a crucial position in consumer electronics and industrial equipment due to their short charging time, long lifespan, and excellent temperature characteristics. However, despite significant progress in the field of supercapacitors in China, the high-end button-type supercapacitor market remains largely monopolized by companies from Japan, South Korea, and the United States, particularly in high-voltage and small-size products, which are currently absent from the domestic market.

[0003] Currently, the maximum charging voltage of conventional button-type supercapacitors in my country generally does not exceed 2.7V, and every 0.1V increase in voltage leads to a significant reduction in product lifespan. Furthermore, while button-type supercapacitors with diameters of 9mm or 11mm and above have achieved mass production, smaller products with diameters of 4mm or 6mm face numerous technical challenges in automated production, including issues such as small component dimensions and insufficient positioning and transfer accuracy. Simultaneously, existing electrolyte systems such as TEA+PC or SBP+AN typically only achieve a maximum operating voltage of 2.85V, which is insufficient to meet the demands of high-voltage applications. These technical bottlenecks limit the development of high-end button-type supercapacitors in China, resulting in a high dependence on imports and severely restricting the improvement of the industry's competitiveness. Summary of the Invention

[0004] The purpose of this invention is to provide a double-layer button-type supercapacitor and its production line. Through innovative structural design, electrolyte system design, and production line design, it solves the technical problems of limited operating voltage of existing capacitors and the difficulty in mass production of small-diameter products. At the same time, it breaks the foreign monopoly and fills the domestic product gap.

[0005] According to one aspect of the present invention, a double-layer button-type supercapacitor is provided, comprising at least a positive electrode, a negative electrode, an electrolyte system, a shell, a separator, and leads. The outer diameter of the shell is 6.60 mm and the total thickness is 1.7 mm. The thickness of the positive electrode is 0.5 mm, the thickness of the negative electrode is 0.5 mm, and the length of the leads is 9.1 mm, the width is 2 mm, and the height is 1.5 mm.

[0006] In some embodiments, the electrolyte system comprises a bis-spirocyclic quaternary ammonium tetrafluoroborate, sulfolane cyclobutane, and dimethyl sulfone, wherein the bis-spirocyclic quaternary ammonium tetrafluoroborate accounts for 30% of the total mass, the sulfolane cyclobutane accounts for 50%, and the dimethyl sulfone accounts for 20%.

[0007] In some embodiments, the maximum operating voltage of the electrolyte system is 3.3V.

[0008] In some embodiments, the positive electrode is made by mixing activated carbon powder and conductive carbon black in a mass ratio of 7:3 and then adding polyvinylidene fluoride binder; the negative electrode is made by mixing graphene and conductive carbon black in a mass ratio of 9:1 and then adding polyvinylidene fluoride binder.

[0009] In some embodiments, the positive electrode is coated on an aluminum foil current collector, and the negative electrode is coated on a copper foil current collector.

[0010] In some embodiments, the diaphragm is a polypropylene microporous membrane with a thickness of 25 μm.

[0011] In some embodiments, polarity markings are indicated on both the top and bottom of the housing.

[0012] According to another aspect of the present invention, a fully automated positive and negative electrode patch production line is provided for manufacturing double-layer button supercapacitors, including video recognition positioning points and a robotic arm, wherein the video recognition positioning points are used for real-time image acquisition and processing to guide the robotic arm to complete workpiece transfer.

[0013] In some embodiments, the single-unit production capacity of the robotic arm reaches over 40,000 units per shift.

[0014] According to another aspect of the present invention, a fully automated assembly and sealing production line is provided for manufacturing double-layer button supercapacitors, including a multi-point clamping structure and segmented pressure control, wherein the multi-point clamping structure is used to fix the workpiece, and the segmented pressure control is applied in three stages: initial contact pressure, medium pressure and final high pressure.

[0015] Compared with existing technologies, this invention offers the following advantages: The use of a novel electrolyte system increases the maximum operating voltage of the supercapacitor from the traditional 2.85V to 3.3V, expanding the product's application range. The design and implementation of a fully automated production line solves the problem of insufficient positioning accuracy for micro-components, significantly improving production efficiency and reducing labor costs. In particular, the application of video recognition technology and segmented pressure control technology further enhances the automation level of the production line and the consistency of product quality. Furthermore, by optimizing the interface characteristics of electrode materials and electrolyte, the goal of low ESR and high cycle life is achieved, improving the overall performance of the product. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a detailed schematic diagram of the parameters of the capacitor of the present invention. Detailed Implementation

[0018] The following will refer to the appendices in the embodiments of the present invention. Figure 1 The technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0019] This embodiment addresses the aforementioned problems by developing a button-type supercapacitor capable of stable operation under high voltage conditions and featuring a small size, while also resolving the technical challenges in its automated mass production. Through an innovative electrolyte system employing a dual-spirocyclic ammonium tetrafluoroborate (SBP-BF4) + sulfolane + dimethyl sulfone, the voltage limitations of traditional electrolyte systems are overcome, enabling the product to operate at 3.3V, significantly improving performance and application range. Simultaneously, a self-developed fully automated production line solves the technical difficulties in positioning, assembly, and sealing of micro-miniature supercapacitors, achieving efficient automated production of 6mm diameter button-type supercapacitors. This technological innovation not only fills a gap in domestic high-end products but also provides the industry with a new technological path and development direction.

[0020] This invention provides a double-layer button-type supercapacitor and a production line, which, in conjunction with the attached... Figure 1 Please provide a detailed explanation.

[0021] First, the design and preparation process of the electrolyte system in this invention are introduced. This electrolyte system consists of tetrafluoroborate bis(spirocyclic) quaternary ammonium salt (SBP-BF4), sulfolane, and dimethyl sulfone. After multiple experimental optimizations, the ratio was determined to be 30% SBP-BF4, 50% sulfolane, and 20% dimethyl sulfone by mass. During preparation, SBP-BF4 powder is first dissolved in sulfolane and stirred at 300 rpm for 3 hours under constant temperature and stirring conditions to ensure complete dissolution. Then, dimethyl sulfone is added and stirring continues for 1 hour, finally obtaining a uniform and transparent electrolyte. The most significant feature of this electrolyte system is its high operating voltage of 3.3V, significantly better than the 2.85V upper limit of traditional TEA+PC or SBP+AN systems. Chemical stability tests at high temperature (60℃) and low temperature (-10℃) show that the leakage current can be controlled within ≤150uA within 0.5 hours. Simultaneously, the ion migration rate and interfacial stability are optimized, thereby reducing energy loss and improving withstand voltage.

[0022] Next, we discuss the fabrication processes of the positive and negative electrode sheets. The positive electrode material is a mixture of activated carbon powder and conductive carbon black at a mass ratio of 7:3, with an appropriate amount of polyvinylidene fluoride (PVDF) added as a binder, resulting in a ratio of 85:10:5. This mixture is then added to N-methylpyrrolidone (NMP) solvent to form a slurry, which is coated onto an aluminum foil current collector. After drying and rolling, a positive electrode sheet with a thickness of 0.5±0.2 mm is formed. The negative electrode sheet is made by mixing graphene and conductive carbon black at a mass ratio of 9:1, with the same proportion of PVDF binder added, and coated onto a copper foil current collector, also with a final thickness of 0.5±0.5 mm. This material combination not only increases the specific surface area of ​​the electrode but also significantly reduces the internal resistance, thus meeting the requirements for high power output.

[0023] Regarding the processing and assembly of the outer casing, its outer diameter is designed to be 6.60mm with a tolerance range of +0.04mm, and the total thickness is 1.7±0.2mm, ensuring product miniaturization and assembly precision. The casing is made of stainless steel using a stamping process. "+" and "-" symbols are marked on the top and bottom respectively to clearly indicate the positive and negative electrode positions, preventing damage or failure due to reverse polarity. During assembly, a diaphragm is placed between the positive and negative electrode plates. The diaphragm material is a 25μm thick polypropylene microporous membrane, possessing excellent ion permeability and mechanical strength. The diaphragm is punched using high-frequency vibration cutting technology. By adjusting the vibration frequency and cutting speed, a fast and burr-free cutting effect is achieved, avoiding edge defects that may occur with traditional shearing methods.

[0024] In the product performance testing phase, the operating temperature range was set from -10℃ to +60℃, the rated operating voltage was 3.3V, the nominal capacitance was 0.22F, the allowable capacitance deviation was -20% to +80%, and the equivalent series resistance (ESR) was controlled within ≤200Ω. Durability testing showed that after continuous operation at 60℃ for ≥1000 hours, the product maintained stable performance parameters, demonstrating excellent high-temperature stability and long lifespan. Low-temperature performance testing showed that the capacitance was ≥80% of the nominal capacitance at -10℃, ensuring normal operation in low-temperature environments. Cycle life testing results showed ≥200,000 cycles, reflecting the product's high reliability and long service life.

[0025] The applications of this invention cover fields such as solar-powered watches, handheld devices, MP3 players, PMPs, backup power supplies for mobile phone clocks, digital cameras, PDAs, digital photo frames, radar detectors, dashcams, and in-vehicle DVRs. For example, in solar-powered watches, the high voltage characteristics of this product enable it to maintain a long battery life even under low light conditions; while in dashcams, its wide operating temperature range and high cycle life ensure stable operation in extreme environments. By optimizing the electrode materials and electrolyte interface characteristics, the goals of low ESR and high cycle life are achieved, thereby improving overall performance.

[0026] Preferably, to support the production of the aforementioned double-layer button-type supercapacitors, this invention also relates to the design and implementation of a fully automated positive and negative electrode patch production line. This production line is the first domestic production line for 6mm diameter button-type supercapacitors, specifically optimized to address the issues of small size and insufficient positioning and transfer accuracy of micro-components. Video recognition technology is introduced into the production line. Through a real-time image acquisition and processing system, combined with the precise motion control of the robotic arm, accurate transfer of workpieces between processes is achieved. The video recognition positioning point is located at a specific position on each workpiece. After capturing its position information through a camera, it is fed back to the control system, thereby guiding the robotic arm to complete the picking, placement, and assembly actions. The single-unit production capacity reaches over 10,000 units per shift, enabling unattended production. Furthermore, pad printing technology in the production line is used to mark "+" and "-" symbols on the outer shell surface, with a printing accuracy of ±0.05mm, ensuring clear and visible markings.

[0027] Preferably, to support the production of the aforementioned double-layer button-type supercapacitors, this invention also involves a fully automated assembly and sealing production line, which is also the first domestic production line for 6mm diameter button-type supercapacitors. This production line employs a multi-point clamping structure for product positioning, using multiple pneumatic grippers to fix the workpiece from different directions, ensuring stability during assembly. The shell-closing process utilizes segmented pressure control technology, applying pressure in three stages: the first stage is initial contact pressure, the second stage is medium pressure to expel internal air, and the third stage is final high pressure to ensure a tight fit between the shell and internal components. This pressure control strategy effectively avoids shell deformation caused by applying excessive pressure at once, while ensuring sealing performance. The single-unit shift capacity of the entire production line also reaches over 40,000 units, further improving production efficiency and reducing labor costs.

[0028] In summary, this invention has successfully developed a miniature, high-voltage 3.3V double-layer button supercapacitor.

[0029] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the scope of the invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0030] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A double-layer button-type supercapacitor, characterized in that, It includes at least a positive electrode, a negative electrode, an electrolyte system, a housing, a separator, and pins. The outer diameter of the housing is 6.60 mm and the total thickness is 1.7 mm. The thickness of the positive electrode is 0.5 mm and the thickness of the negative electrode are both 0.5 mm. The pins are 9.1 mm long, 2 mm wide, and 1.5 mm high.

2. The capacitor according to claim 1, characterized in that, The electrolyte system is composed of tetrafluoroborate bispirocyclic quaternary ammonium salt, sulfolane cyclobutane, and dimethyl sulfone, wherein the tetrafluoroborate bispirocyclic quaternary ammonium salt accounts for 30% of the total mass, the sulfolane cyclobutane accounts for 50%, and the dimethyl sulfone accounts for 20%.

3. The capacitor according to claim 2, characterized in that, The maximum operating voltage of the electrolyte system is 3.3V.

4. The capacitor according to claim 1, characterized in that, The positive electrode is made by mixing activated carbon powder and conductive carbon black in a mass ratio of 7:3 and then adding polyvinylidene fluoride binder; the negative electrode is made by mixing graphene and conductive carbon black in a mass ratio of 9:1 and then adding polyvinylidene fluoride binder.

5. The capacitor according to claim 4, characterized in that, The positive electrode is coated on an aluminum foil current collector, and the negative electrode is coated on a copper foil current collector.

6. The capacitor according to claim 1, characterized in that, The diaphragm is a polypropylene microporous membrane with a thickness of 25 μm.

7. The capacitor according to claim 1, characterized in that, The top and bottom of the outer casing are marked with polarity indicators.

8. A fully automated positive and negative electrode patch production line for manufacturing the double-layer button supercapacitor as described in claim 1, characterized in that, It includes video recognition positioning points and a robotic arm, wherein the video recognition positioning points are used for real-time image acquisition and processing to guide the robotic arm to complete workpiece transfer.

9. The production line according to claim 8, characterized in that, The single-unit production capacity of the robotic arm reaches over 40,000 units per shift.

10. A fully automated assembly and sealing production line for manufacturing the double-layer button-type supercapacitor as described in claim 1, characterized in that, It includes a multi-point clamping structure and segmented pressure control. The multi-point clamping structure is used to fix the workpiece, and the segmented pressure control is applied in three stages: initial contact pressure, medium pressure, and final high pressure.

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