China’s updated GB 38031-2025 battery safety standard takes effect in July 2026, tightening requirements for how well high-voltage battery systems must contain the corrosive gases, heat and pressure generated during a thermal runaway event. Battery housing seals are one of the interfaces now under sharper scrutiny. WEVO-CHEMIE has developed WEVOSIL 23130, a liquid silicone rubber (LSR) formulated specifically for formed-in-place gasket (FIPG) sealing of EV battery packs.

The material uses chemical adhesion on both sides of the seal, unlike conventional cured-in-place gaskets (CIPGs) that rely primarily on mechanical compression. Adhesive strength exceeds 2 MPa, which helps the seal hold its geometry when internal gas pressure spikes during a runaway event, without forming critical decomposition products.

WEVO says that processing fit for automated battery production drove much of the formulation work. WEVOSIL 23130 is filler-free, giving it consistent rheological behavior through standard mixing and dosing systems and static mixers, including on complex 3D housing geometries. Pot life exceeds 24 hours at room temperature, while localized infrared heating to 140 °C achieves initial curing in under 5 minutes—a combination that accommodates both continuous production and unexpected line stoppages on large battery pack assemblies.

The material also blocks moisture ingression and maintains mechanical integrity across the thermal and chemical stress range typical of automotive battery environments.

WEVO-CHEMIE, headquartered near Stuttgart, also offers RTV-2 silicones for battery thermal management potting, structural adhesives, gap fillers and electronic assembly protection.

Source: WEVO-CHEMIE