Researchers at the materials research division of Risø DTU in Denmark are developing a new lithium-air (Li-air) vehicle battery that is lightweight, holds a lot of energy, and could enable car-makers to fully electrify larger vehicles. Theoretically, Li-air batteries could have the same energy density as gasoline, which would make it feasible to electrify large tractor-trailer trucks that can’t run on present-day lithium-ion batteries. Researchers working on the batteries believe they can power a vehicle for up to 500 miles on a single charge — no gasoline required.
“If we succeed in developing this technology, we are facing the ultimate breakthrough for electric cars, because in practice, the energy density of Li-air batteries will be comparable to that of petrol and diesel, if you take into account that a combustion engine only has an efficiency of around 30 per cent,” says Tejs Vegge, senior scientist in the Materials Research Division. The batteries feature a lithium electrode and a porous carbon cathode — during electrical discharge, the battery allows oxygen to react with lithium to create lithium peroxide, and during charging the action is reversed to release the oxygen.
One end of the battery casing is left open so that oxygen can flow freely in and out during the process. Although the battery technology has been proven to work in laboratory situations, the researchers have a handful of hurdles they will need to cross in order to bring this technology to market. They are currently trying to double the energy capacity of the battery, and they have also realized that the battery can get choked by regular air — the researchers have found best results with pure oxygen, which can limit the battery’s supply of air, causing it to stop working. One last hurdle is charging — current Li-air prototypes can only handle 50 charges, and researchers need them to handle upwards of 300 to be commercially viable.
Via Science Daily