New Li ion battery design offers 10x capacity

A new type of lithium ion battery offering up to ten times the battery life and charging speed of current-generation cells has been announced.

Battery life is one of the biggest hurdles to technological advancement - particularly when it comes to mobiel devices. The biggest gaming laptops last only a couple of hours, 'exoskeleton' robots require external generators or power cables, and electric cars need a thousand or more batteries of current generation Li ion technology to keep them going for a hundred or so miles. Charging time can also be a problem.

However a team from NorthWestern University in the US could be pointing the way to the future of mobile power. Recently publishing their findings in the journal Advanced Energy Materials, the group's hypothesis for future designs makes for some very interesting reading.

Hexus reports that the team's design works by changing the structure of the graphene sheets of a Li ion battery by inserting modules of silicon between them. This material has been considered in the past, since it's able to store four lithium ions per atom of silicon, whereas graphene can only hold one lithium atom per six carbon.

However the traditional problem with using silicon lies in the fact that the semiconductor has a tendency to flex and expand during charging, leading to a loss of capacity over time. The NorthWestern method uses clusters of silicon between sheets of graphene, allowing for the structure to be maintained while increasing the cell's charging capacity at the same time.

Charging time would also be improved, as the new method utilises 'holes' in the graphene sheets to funnel lithium ions straight to the silicon clusters and the next sheet of graphene. In current batteries, lithium ions must travel around each sheet in turn, slowing the process down dramatically.

It's thought that this technology could become commercially available within three to five years.