Three times the power
Boffins working at the University Of Waterloo think they have come
up with a lithium battery that can store and deliver more than three times the
power of conventional ones.
Opening the champers, Linda Nazar, David Xiulei
Ji and Kyu Tae Lee are one of the first to demonstrate robust electrochemical performance for a lithium-sulphur battery. According to the magazine Nature
Materials, which we get for the spot the ball competition, boffins have been
coveting the idea of a lithium-sulphur batteries for 20 years.
Apparently if
you add the two chemistries together you get much higher energy densities and
you can buy sulphur much cheaper than anything that goes under the bonnet of
current lithium batteries. The boffins have been stumped by the batteries
cathode because they had been unable to create reversible electrochemical
reaction at high current rates, the electrically-active sulphur needs to remain
in the most intimate contact with a conductor, such as carbon.
However during
a lightning storm in a deserted castle, the team hit on the idea of tackling the
problemat the nanoscale level. The team built a structure of 6.5 nanometre
thick carbon rods separated by empty three to four nanometre wide channels.
Packed the gaps between them with melted sulphur which cooled and formed sulphur nanofibres. This created a huge surface area of the active element to
carbon and lots of juice.