November 28, 2011:
The U.S. Army and the Marine Corps are finally getting fuel cell power systems that meet their needs, especially for troops out in the field for days, or weeks, at a time. The most popular new system is the XX55 Fuel Cell. This 1.6 kg (3.5 pounds) device can supply 40 watts an hour for five hours, or peak output of 55 watts for a shorter time. The XX55 has been in development for over four years, and began field testing three years ago. The XX55 is powered by small methanol cartridges. These can be changed without interrupting operation. For units unable to get back to vehicle (most of which are equipped to recharge batteries via their electrical system), XX55 provides a suitable substitute.
The primary use of devices like the XX55 is to reduce the growing load of batteries carried into combat. Soldiers are sometimes carrying more batteries than bullets. For some infantry operations, especially those lasting 72 hours or longer troops are required to haul up to 13.6 kg (30 pounds) of batteries. Special Forces are particularly hard hit by this, as they often have to go in by foot, to avoid detection, and set up a surveillance operation that consumes a lot of batteries. This is very common in Afghanistan.
Before the XX55 came along, the army used a heavier 2.7 kg (six pound) fuel cell for these multi-day field operations. The small cartridges of methanol are much lighter to ship, and carry, than batteries, and deliver much more electricity per pound than conventional batteries.
The lightweight fuel cells are starting to show up in the civilian market. The first models were expensive (several times the cost of a comparable gasoline powered generator), but the intended market, initially, was backpackers, and the many soldiers who buy additional equipment with their own money. Militarized fuel cell systems began entering service over the last few years. But some troops bought commercial versions as soon as they were available. Toshiba offered a 289 gram (ten ounce) fuel cell that could recharge two cell phones at once. But these devices cost $300 and the 50 ml (two ounce) methanol cartridge cost $30.
A major problem with fuel cell devices like the Toshiba model was that it was mainly for items like cell phones and iPods, or anything that could get its charge via a USB connector. For military use, you need a device that can recharge common batteries, and specialized ones for military equipment. Technically, that is a simple matter, as is scaling up the current miniature fuel cell devices (about the size of a hand held game player) to provide more power. This is why the XX55 was so popular. It produced enough power to recharge most batteries found in infantry units. This was actually a significant bit of engineering, as fuel cell technology was not as easy to scale up as originally thought.
