TOKYO—Honda Motor Co. and General Motors Co. plan to set up a joint assembly plant to manufacture fuel cells. The goal is to reduce the market price of fuel-cell vehicles to levels that can compete with gas-electric hybrid vehicles.

AICHI, Japan—Toyota has unveiled a new assembly line here for its Mirai sedan, which is powered by hydrogen fuel cells. The line is expected to produce 700 units this year, expanding to 2,000 units in 2016 and 3,000 units in 2017.

TORRINGTON, CT—FuelCell Energy plans to spend $65 million to expand its assembly plant here, creating up to 325 jobs over the next four years.

TORRINGTON, CT—FuelCell Energy will invest $65 million to expand its assembly plant here. The project could create up to 325 jobs over the next four years.

MALTA, NY—General Electric has opened a new fuel cell manufacturing facility here.

3M Co. is famous for sand paper, Scotch tape and Post-it notes. But, it’s also bullish on the future of fuel cell technology. The company is a leading provider of materials that are critical to fuel cells, such as fluoropolymers, membrane materials and advanced ceramics.

Many experts tout fuel cells as one of the cleanest forms of green energy, because the devices reduce CO2 emissions and provide greater energy efficiency than combustion engines.