Semiconductors are used in the hybrid system’s Power Control Unit, responsible for managing the flow of electricity between the motor-generator and battery.

Toyota says the PCU accounts for 25% of the electrical power loss in a hybrid, of which 20% is lost as heat through the semiconductors.

Developed in-house with Denso, the new technology replaces the traditional silicon power semiconductor with a silicone carbide compound, which is designed to lose less energy as heat. 

Tests with prototype vehicles have shown the new technology improves fuel economy by 5% compared on the Japanese test cycle, while reducing the size of the PCU by 80%.

Research is ongoing in a clean room facility at Toyota’s Hirose plant in Japan ahead of public road trials within the year, the carmaker said, and the improvements are applicable with all electrically-driven vehicles.