The transmission accuracy of the planish machine for supercapacitors is one of the core factors determining battery dimensional accuracy. Its impact permeates the entire battery manufacturing process, from electrode winding to cell packaging. Even minute deviations in the transmission system can trigger a chain reaction, ultimately leading to dimensional deviations, performance degradation, and even safety hazards. Transmission accuracy essentially refers to the accuracy of motion and power transmission by the machine tool's feed mechanism. If there are gaps, insufficient rigidity, or component wear in the transmission chain, the actual feed rate will deviate from the theoretical value. This deviation is amplified in cylindrical battery manufacturing because the precision requirements for processes such as tab alignment, winding tension, and sealing welding are extremely high.
In the electrode winding stage, transmission accuracy directly affects the cutting and alignment of the tabs. The tabs of a cylindrical battery are a critical structure for current conduction, and their positional accuracy needs to be controlled at the micrometer level. If the planish machine's transmission system has backlash errors or speed fluctuations, the movement trajectory of the tab cutting tool will deviate from the preset path, resulting in inconsistent tab lengths and spacing deviations, which in turn can cause tab misalignment after winding. This misalignment not only reduces the battery's energy density but can also cause overheating or even thermal runaway during charging and discharging due to localized current concentration. Furthermore, winding tension control relies on the stability of the transmission system; tension fluctuations can lead to electrode wrinkling or stretching, resulting in poor cell diameter uniformity and affecting subsequent packaging and casing processes.
Sealing welding is another critical step affected by transmission accuracy. Cylindrical batteries require laser welding to seal the casing and cover plate; welding accuracy directly determines the battery's sealing performance and safety. If the flattening machine's transmission system vibrates or shifts during welding, the laser focus will deviate from the weld center, leading to weak welds or even weld penetration. The former can cause electrolyte leakage, while the latter may damage the nickel plating on the casing, accelerating corrosion. For large cylindrical batteries, with lower casing strength and more internal electrolyte and higher internal pressure, the requirements for pressure resistance and stability in sealing welding are even more stringent; even minor deviations in transmission accuracy can become a cause of safety hazards.
Transmission accuracy is equally crucial for controlling the battery's height dimensions. The height of cylindrical batteries requires precise flattening and shaping of the cells after the electrode sheets are wound using a leveling machine. If the transmission system experiences axial movement or angular wobbling, a height difference will occur at both ends of the cell, preventing the battery from being properly installed into the module or battery pack. This height deviation also affects the overall structural stability of the battery pack, potentially causing battery displacement, short circuits, or even fires under vibration or impact. Furthermore, batteries with out-of-tolerance height dimensions will have increased internal resistance due to poor contact, reducing charge and discharge efficiency and shortening cycle life.
The impact of transmission accuracy also affects battery manufacturing yield and cost. A high-precision transmission system can reduce scrap rates caused by dimensional deviations, lowering raw material waste and rework costs. For example, insufficient electrode alignment accuracy requires manual correction or scrapping of an entire batch of cells; poor sealing welding requires additional inspection and rework processes. Low-precision transmission systems, on the other hand, may accumulate errors over long-term operation, forcing companies to frequently stop for maintenance, impacting production efficiency and delivery cycles. To improve the transmission accuracy of the planish machine for supercapacitor, a comprehensive approach is needed from three aspects: design, manufacturing, and maintenance. During the design phase, high-rigidity transmission components, such as precision ball screws and low-backlash reducers, should be selected, and the transmission chain structure should be optimized to reduce error transmission. During the manufacturing phase, strict control of part machining accuracy is required, employing processes such as CNC grinding and heat treatment to improve the wear resistance and stability of transmission components. During the maintenance phase, regular inspections of transmission system clearance, lubrication status, and component wear are necessary, with timely replacement of aging parts and parameter calibration. Furthermore, introducing a real-time closed-loop control system, which monitors transmission errors through sensors and dynamically adjusts them, can further counteract external interference and achieve micron-level precision control.
