A new direct-methanol fuel cell (DMFC) stack has been developed which offers greater gravimetric energy density.

According to a report from Japan Chemical Week, NEC has created a DMFC which offers gravimetric energy density of 400 kWh/kg, which is more than double that of a lithium ion secondary battery.

The company managed to reduce methanol crossover by 30 per cent through deploying a swelling-resistant hydrocarbon membrane instead of fluorine based membranes and was able to optimise the concentration and amount of fuel used by establishing a new methanbol-electrode assembly.

As a result, the DMFC is able to deliver a power output density of 45 mW/cu cm while using a methanol concentration of 50 per cent by volume.

Ÿ Adfero Ltd