Today, CATL and BYD jointly announced that their latest generation of sulfide solid-state battery packs have completed 1.5 million kilometers of extreme environment road testing and officially entered the pre-mass production validation stage. The core of this breakthrough lies in the "high-voltage and electrolyte-corrosion resistant fluorosilicone composite insulation sheathing" used on the battery pack's high-voltage wiring harnesses and cell connections. Developed jointly by the Ningbo Institute of Materials Technology, Chinese Academy of Sciences, and Anhui Guofeng New Materials, this material successfully solved the insulation aging problem of solid-state batteries under high voltage (>800V) and in the presence of trace liquid wetting agents, extending the battery system's design life to 25 years and clearing the final obstacle for the launch of flagship electric vehicles with a range exceeding 1,000 kilometers. According to the project's technical lead, while the new generation of solid-state batteries offers significantly improved safety, their sulfide electrolytes are extremely sensitive to moisture and prone to partial discharge under high voltage. Traditional silicone rubber sheathing is susceptible to swelling or electrical treeing breakdown under these conditions. The R&D team constructed a dense molecular barrier by introducing perfluoropolyether side chains and nano-silica cross-linking points. This not only results in "zero swelling" when exposed to the electrolyte but also increases corona resistance life by more than ten times. During the two-year road test, the sheathing endured drastic temperature variations from -45°C in Mohe to +60°C in Turpan, as well as high humidity and high salt spray environments. Its insulation resistance value remained at over 99% of the initial value throughout, with no micro-cracks or leakage detected. Industry analysts point out that this material breakthrough has eliminated the last safety concern hindering the large-scale commercialization of solid-state batteries. It is expected that several flagship electric vehicle models launching in the second half of 2026 will be the first to adopt this technology, further consolidating China's leading global position in core materials for the new energy vehicle industry. IOTA FLSR3040 Fluorosilicone potting adhesive