A research team from the Korea Institute of Science and Technology (KIST) has begun road testing an EV powered by a magnesium-air power pack, in what the institute describes as a world first.
Magnesium air fuel cell chemistry uses a magnesium anode and oxygen drawn from the air as a cathode. The Institute claims it has up to five times the energy density of a similar sized lithium-ion battery, yet takes less time to recharge. This is why it’s seen by the industry as one of the more promising prospects in alleviating the range problems that have dogged global electric vehicle sales to date.
On the downside, while magnesium-air systems can store energy efficiently, getting it in and out is another matter. Both sides of the process are less responsive than other materials – magnesium (pictured, in crystalline form) is an inefficient reactor, while the atmospheric oxygen cathode has low response speeds. All of which limits its uses in the energy-hungry business of getting and keeping a vehicle moving.
The Institute has released video of the road test (see below). KIST is coy about the details, but says the team “employed various substances to change the chemical composition of the magnesium anode and air cathode and improve the reaction efficiency and speed.” The resulting package, however, “has an energy discharge double that of a conventional battery.” And when it runs low, recharging simply involves replacing a magnesium plate and the electrolytic solution – salt water.
The team, led by Dr Cho Byung-won of the Centre for Energy Convergence Research, says it’s still early days in the technology’s path to commercialisation – if it proves viable. It will take some time for the industry to overcome the cost barrier, which the team puts at around three times that of a conventional internal combustion vehicle.
Dr Cho Byung-won suggests, however, that costs will likely come down enough to find viability with further development of the technology itself and recycling methods for magnesium hydroxide.
Read the latest news and reviews on your mobile, iPhone or PDA at carsales' mobile site...