- Hydrogen Pellets Could Obsolete Batteries
- Hydrogen fuel pellets being perfected for military applications are preparing to go commercial, replacing conventional batteries with electricity generating fuel cells.Hydrogen fuel pellets that are cheaper and weigh less than half what batteries weigh could soon be replacing them thanks in part to a new recharging technology.
Using a Purdue University innovation, General Atomics (San Diego) claims its hydrogen fuel pellets will save the Army $27 million a year and cut a solder's backpack by 10 pounds. In addition, General Atomics' hydrogen fuel pellets could someday be replenished after use by virtue of technology from the guys who invented the atomic bomb—Los Alamos National Laboratory (LANL).
"Many of the technologies we take for granted in our everyday lives were originally created for military or space exploration purposes," according to the Purdue professor Veeraraghavan Ramachandran. "We've developed a way to use a very stable and safe compound that can release pure hydrogen gas on demand without any toxic or corrosive byproducts."
Ball-and-stick model of the ammonia-borane molecule, NH3BH3, yields up its hydrogen when heated so it can be converted into electricity by a fuel cell.Fuel cells are already available for recharging gadgets, but their cartridges must be discarded when spent. These new hydrogen fuel pellets, on the other hand, hold the promise of reuse by virtue of a new process developed separately at LANL.
When hydrogen fuel pellets are heated, the hydrogen gas given off is converted by the fuel cell into electricity, potentially replacing traditional batteries in everything from smartphones to laptops to electric cars. Being perfected for the military first, Purdue claims its process is suitable for mass production of consumer models too.
According to Ramachandran, Purdue's new process for making hydrogen-bearing fuel pellets lowers their price 20 times—from $2 to 10 cents per gram for the active ingredient (ammonia borane). The process locks hydrogen molecules in a safe, stable and compact pellet about the size of a marble. The pellets do not lose their charge, like batteries, but can be stored indefinitely without degradation. General Atomics fashions the pellets into tubes about the size of a flashlight for soldiers to pop into fuels cells where they supply electricity until their hydrogen is exhausted.
Fuel cells combine hydrogen and oxygen from the air to produce water, and in the process releasing electricity on demand.Separately, Los Alamos National Laboratory and the University of Alabama, working within the U.S. Department of Energy (DoE), claims to have perfected a method of recharging hydrogen fuel pellets, potentially lowering their price even further. Since ammonia borane stores four times more hydrogen than the gas by itself, these fuel pellets pack enough punch to enable vehicles to travel 300 miles before refueling—a milestone the DoE says is a prerequisite to powering commercial vehicles.
The Los Alamos Labs method regenerates ammonia borane with a "one pot" technique using hydrazine and liquid ammonia. The technique, however, cannot be used on-the-spot like refilling your tank at the gas station. Instead, the tubes containing the spent hydrogen fuel pellets would be removed and replaced with new ones in a matter of seconds. Then the spent tubes would be sent back to the factory for replenishing using LANL's process.