LAS VEGAS — Daimler, the world's largest truck manufacturer, could commercialize a hydrogen-powered city bus in the next two to three years, r&d boss Markus Schäfer told reporters at CES last week.

While electrification is sweeping the passenger-car side of the industry, fuel cells are a more promising option for larger vehicles because they have better energy density than battery-electric vehicles.

Lithium ion battery chemistry currently struggles to deliver the range long-haul trucks require, Schäfer said.