Can LSR Be Used in Automobiles/New Energy Batteries?
Liquid silicone rubber (LSR) is not only suitable for automobiles
Liquid silicone rubber (LSR) is not only suitable for automobiles and new energy batteries—it has become an essential material for these applications. As the automotive industry transitions toward electrification, LSR is increasingly used in electric vehicle (EV) battery systems, high-voltage connectors, cooling circuits, and thermal management components. Its unique combination of thermal stability, electrical insulation, sealing performance, and long-term durability makes it well suited for the demanding conditions found in modern vehicles.
Why LSR Is Suited for Automotive and EV Applications
LSR offers several properties that are critical for automotive and new energy battery systems. It maintains flexibility and performance across a wide temperature range, typically from -40°C to 200°C. It provides excellent electrical insulation, which is essential for high-voltage components. LSR also exhibits low compression set, meaning it maintains its sealing force even after prolonged compression. Additionally, it resists aging, chemicals, and environmental exposure, ensuring long service life in harsh conditions.
Sealing High-Voltage Battery Housings
One of the most important applications of LSR in new energy vehicles is sealing high-voltage battery housings. As battery safety regulations tighten, particularly China's GB 38031-2025 standard that takes effect in July 2026, manufacturers must ensure that battery systems can contain corrosive gases, heat, and pressure during a thermal runaway event.
LSR is being used in formed-in-place gasket (FIPG) systems for battery housing seals. A notable example is WEVOSIL 23130, an LSR developed specifically for this application. This material uses chemical adhesion on both sides of the seal, achieving adhesive strength exceeding 2 MPa, which helps the seal hold its geometry when internal pressure spikes during a runaway event. The LSR creates a reliable barrier against gases and smoke while maintaining mechanical integrity under thermal and chemical stress.
High-Voltage Connector Seals
High-voltage connectors in electric vehicles require durable sealing to prevent moisture ingress and maintain electrical integrity. Elkem Silicones developed BLUESIL™ LSR 3935 specifically for sealing high-voltage connectors in new energy vehicles. This material offers a self-lubricating surface, excellent compression set resistance, and outstanding thermal stability, ensuring reliable long-term sealing even under high temperatures.
Dow also offers LSR for electrical connector seals, highlighting consistent sealing performance at high and low temperatures, low compression set, and options for self-lubrication to ease assembly.
Cooling Circuit Seals
Battery cooling systems in EVs require seals that can withstand prolonged contact with coolant fluids. Wacker Chemie developed ELASTOSIL® LR 3822, an oil-exuding LSR designed for coolant-resistant sealing elements in EV traction battery cooling circuits. This material continuously releases silicone oil from its surface, creating a lubricant film that facilitates assembly. It maintains most of its mechanical properties even after 1,000 hours of storage in a glycol-water mixture at 125°C, demonstrating excellent coolant resistance.
Thermal Management Components
LSR is also used for thermal management in battery systems. Thermally conductive LSR grades are available for applications such as heat transfer pads, gaskets, and battery cooling components. Momentive's NEVSil™ LSR TC330 is a thermally conductive two-component LSR developed for new energy vehicle applications. It provides an injection-moldable option for creating a thermal path between heat sources and heat sinks, helping to remove heat generated by electronic components and battery systems.
Flame-Retardant and Safety Components
Safety is a critical concern in EV battery systems. Flame-retardant LSR grades are available for applications requiring UL94 V-0 performance. Momentive's NEVSil™ LSR FR830 offers flame-retardant properties equivalent to UL94 V-0 at 1mm thickness, along with excellent heat resistance and self-extinguishing properties. These characteristics help reduce the risk of ignition and suppress the generation of harmful gases in high-voltage environments.
General Automotive Applications
Beyond new energy batteries, LSR is used in a wide range of traditional automotive applications. It is used for gaskets in engines, transmissions, and braking systems due to its high oil resistance and thermal stability. LSR seals are also used in electrical connectors throughout the powertrain. The material's resistance to automotive fluids, vibration, and temperature extremes makes it suitable for demanding under-hood environments.
Conclusion
LSR is not merely compatible with automobiles and new energy batteries—it is a critical enabling material for modern vehicle design. From sealing high-voltage battery housings and connectors to managing thermal loads and ensuring safety during thermal runaway events, LSR provides performance characteristics that few other materials can match. As electric vehicle adoption grows and safety regulations become more stringent, the demand for LSR in automotive and battery applications is expected to increase further. For manufacturers and designers working on next-generation vehicles, LSR offers a reliable, high-performance material solution.