All the intelligence displayed by modern smartphones requires considerable energy. The problem: battery capacity hasn't quite kept up.

Portable fuel cells have been around for a long time in the marine, industrial and military sectors but the power-hungry consumer electronics market has yet to bite.

Pike Research notes that the fuel cell industry is eyeing the rapid proliferation of smartphones and tablet computers as an opportunity for growth. Several fuel cell manufacturers and large-scale electronics companies (including Toshiba and Hitachi) have announced and demonstrated micro and small portable fuel cells for several types of portable electronics, and the research firm predicts that 4.5 million PFCs -- mostly in the form of external battery chargers -- will see shipment in 2017.

At a 237 percent compound annual growth rate over the next six years, that's a significant jump.

The industry's reasoning is that new electronics will continue to require high power density for long durations -- and when the power grid isn't available, a fuel cell charger might be. To date, it has proved too difficult to incorporate fuel cell technologies into the devices themselves.

Will consumers desire on-demand energy for their devices, or will they just choose to power down for a break? It's uncertain.

If there's one thing we're sure of, it's this: the less equipment in the bag, the better.

This post was originally published on Smartplanet.com