As part of a lunar polar exploration mission project led by the Japan Aerospace Exploration Agency, Toyota is developing a regenerative fuel cell for the Lunar Cruiser manned pressurized rover. The technologies under development for lunar transport could also find application back on Earth.

A regenerative fuel cell functions as a fuel cell that converts hydrogen and oxygen into electricity and water, and as an electrolyzer that produces hydrogen and oxygen through the application of electrical energy. This dual-mode operation allows the power system to switch between being an energy generator and an energy storage device.

A key challenge for the Lunar Cruiser is operation during the 14-day lunar night without sunlight. Project engineers are looking to the regenerative fuel cell to produce hydrogen and oxygen during daylight hours and then use the fuel cell to supply electricity at night.

In addition to leveraging its own fuel cell advances, Toyota is partnering with Mitsubishi Heavy Industries on marine electrolysis technology to resolve issues pertaining to lightweight storage for both hydrogen and water. Such a development could enable high-efficiency hydrogen production using sunlight, making it compact and lightweight enough to be mounted in vehicles and contribute to carbon neutrality.