Fuel Cells for Robotics: Why They Haven't Caught On Yet

A power source with real theoretical advantages that keeps not quite making it into humanoid robots.

Fuel cells generate electricity directly from a chemical reaction (commonly hydrogen and oxygen), offering potentially much higher energy density than batteries and the ability to 'refuel' quickly rather than waiting through a charge cycle.

Why adoption has been limited

Fuel cell systems need supporting infrastructure — fuel storage (often compressed hydrogen, itself bulky and requiring careful safety engineering), and typically respond more slowly to sudden power demand changes than batteries, which matters for a robot needing instantaneous torque during a recovery motion.

Where they're more plausible

Fuel cells are more actively explored for applications needing very long endurance where refueling infrastructure is practical to establish — some industrial and defense robotics contexts — than for general-purpose humanoids meant to operate flexibly in ordinary indoor human environments without dedicated fuel infrastructure.