The leakage problem of industrial button batteries in high-temperature and high-humidity environments is essentially the result of the synergistic interaction between the internal chemical system and external environmental stress. The highly alkaline components in the electrolyte become more active at high temperatures, easily reacting with the sealing material, leading to failure of the sealing interface. Furthermore, the hot and humid environment accelerates oxidative corrosion of the metal casing, weakening the structural strength and subsequently causing leakage. Therefore, optimizing the sealing structure design requires systematic breakthroughs in three dimensions: material selection, structural innovation, and process control.
Sealing materials are the first line of defense against environmental corrosion. Traditional rubber seals are prone to creep at high temperatures, resulting in a decrease in sealing pressure. Fluororubber, with its excellent high-temperature and chemical resistance, has become a leading alternative. The fluorine atoms in its molecular chain impart extremely low surface energy to the material, effectively blocking electrolyte penetration. Furthermore, high-performance engineering plastics such as polyetheretherketone (PEEK) are used in the sealing framework due to their combined high-temperature resistance and high strength, achieving complementary advantages through material compounding. For example, a sealing structure composed of fluororubber and PEEK ensures the flexibility of the sealing layer while dissipating external stress through a rigid framework, significantly improving sealing reliability.
Structural innovation is key to solving leakage problems. Traditional button batteries use a flat sealing design, which can easily create gaps in the sealing interface due to casing deformation or material aging. The new explosion-proof sealing structure integrates both sealing and explosion-proof functions by introducing a mechanical interlocking mechanism between the explosion-proof column and the clamping sleeve. The explosion-proof column is embedded in the explosion-proof hole of the cover plate, forming an interference fit with the clamping sleeve. When internal pressure increases, the explosion-proof column can be detached in a directional manner, releasing pressure while maintaining seal integrity. Furthermore, the spiral electrode assembly design increases the contact area between the electrolyte and the electrode, reducing local current density, thereby slowing the electrolyte decomposition rate and indirectly reducing the risk of leakage.
The impact of the welding process on sealing performance cannot be ignored. Laser welding technology uses a high-energy-density beam to achieve localized melting, creating a continuous, defect-free weld with significantly improved airtightness compared to traditional resistance welding. During the welding process, energy input must be strictly controlled to avoid deformation of the housing due to an excessively large heat-affected zone. For example, pulsed laser welding, by optimizing the pulse frequency and duty cycle, ensures weld quality while minimizing the heat-affected zone and ensuring housing geometric accuracy. Furthermore, post-weld leak testing is required. Helium mass spectrometry leak detection can identify even tiny leaks with extremely high sensitivity.
The reliability of the sealing structure must be verified through accelerated life testing. By simulating high-temperature and high-humidity environments, the aging rate and structural stability of the sealing material can be quickly assessed. Tests have shown that industrial button batteries sealed with fluororubber exhibit extremely low leakage rates under specific temperature and humidity conditions after long-term testing, far exceeding industry standards. Furthermore, vibration testing verifies the explosion-proof structure's ability to withstand mechanical stress. Under specific frequency and amplitude conditions, no loosening or cracking of the sealing interface is observed.
Process control during the manufacturing process is critical to ensuring sealing quality. The pre-sealant application process uses automated equipment to evenly apply high-performance sealant to the surface of the industrial button battery housing, which forms a reliable seal after curing. This process eliminates the unevenness of manual glue application, and the glue layer can fill microscopic irregularities in the housing, resulting in improved airtightness. Furthermore, the cleanliness and wear of the sealing mold directly impact the seal quality. Regular inspection of mold surface roughness is necessary, and worn molds should be replaced promptly to prevent leaks caused by a loose seal.
Full-chain optimization, from materials to processes, significantly improves the sealing reliability of industrial button batteries in high-temperature and high-humidity environments. By introducing high-performance sealing materials, innovative explosion-proof sealing structures, optimized welding and gluing processes, and combining rigorous reliability verification, a multi-dimensional protection system is established, effectively addressing leakage issues and providing stable and safe energy support for industrial applications.
