Comment on their similarities and their differences.
Fuel Cells last longer than rechargeable batteries (which have a life about 600-1000 recharge cycles -- Li-Ion) Fuel cells you just add more fuel - hydrogen, methanol, etc Fuel Cells have a higher up front cost since most have a platinum (or other rare earth metal) catalyst inside. And you probably pay the same amount as batteries for the proprietary fuel recharge cartridges. So currently FC's are still more expensive. I'm guessing here, but I would think that at a certain low temperature the batteries would work better than the fuel cell since the water that some FC's produce as a by product might freeze and clog the system. FC's don't produce toxic by-products like discarded dead batteries. Some FC's produce CO2 as a by product particularly the methanol type. Hydrogen fueled FC's produce pure water as product.