WEVO develops battery housing silicone seal to meet China’s new safety standards

China’s forthcoming GB 38031-2025 battery safety standard, set to take effect in July 2026, introduces more stringent requirements for high-voltage battery systems, particularly focusing on their ability to contain corrosive gases, heat, and pressure during thermal runaway incidents. One critical area under increased scrutiny is the battery housing seal, which must now demonstrate enhanced performance to prevent hazardous leaks and maintain structural integrity under extreme conditions. In response, WEVO-CHEMIE has developed WEVOSIL 23130, a specialised liquid silicone rubber (LSR) designed specifically for formed-in-place gasket (FIPG) applications in electric vehicle battery packs. WEVOSIL 23130 distinguishes itself from traditional cured-in-place gaskets by employing chemical adhesion on both sides of the seal, rather than relying solely on mechanical compression. This approach results in an adhesive strength exceeding 2 MPa, enabling the seal to retain its shape and resist degradation when exposed to sudden internal pressure spikes during thermal runaway events. The material’s formulation also prioritises compatibility with automated battery production lines, featuring consistent rheological properties without fillers, which ensures smooth processing through mixing and dosing systems, even on complex three-dimensional battery housing designs. The product’s practical benefits extend to its curing profile and durability. WEVOSIL 23130 offers a pot life of over 24 hours at room temperature, allowing flexibility during manufacturing, while rapid curing can be achieved in under five minutes using localized infrared heating at 140°C. This combination supports both continuous production and the management of unexpected line stoppages on large battery assemblies. Additionally, the sealant provides effective moisture barrier properties and maintains mechanical integrity across the thermal and chemical stresses typical of automotive battery environments, addressing key challenges in EV battery safety and longevity. WEVO-CHEMIE, based near Stuttgart, is also active in other areas of battery technology, supplying RTV-2 silicones for thermal management potting, structural adhesives, gap fillers, and electronic assembly protection. The development of WEVOSIL 23130 reflects the company’s commitment to meeting evolving safety standards and production demands in the electric vehicle sector, positioning it as a significant contributor to the advancement of battery system reliability and safety in the face of increasingly rigorous regulatory frameworks.