How can fuel cells be used in electronic appliances?

A. Fuel cells can be as small as the smallest battery, making a fuel cell a possible choice for powering all electronic appliances. Since the fuel cell itself doesn't deplete as a battery does, all that is required for long term power supply is a charge of hydrogen. It has been proposed that batteries as small as hearing aid batteries with a self-contained charge of hydrogen similar to a mini cigarette lighter could compete with current battery technology for all appliances. ... more