Revolutionary Lithium Ion Battery Design to Benefit Mobile Electronic Devices - News Item

Researchers at the University of California, Irvine have developed a new type of lithium battery that could be used to power all kinds of portable electronic devices from mobile phones to laptop computers.

Existing lithium ion batteries generate current when lithium ions flow between a negative and positive terminal. The new battery design increases the power generated by using an array of terminals in a sea of lithium ions, effectively acting as hundreds of batteries in the space usually occupied by a single battery.

The breakthrough in the battery design came when they figured out how to grow tiny rods of carbon. This was achieved by using a polymer which hardened upon exposure to UV light. The polymer was deposited onto a substrate through a perforated mask and removed excess unreacted polymer by etching.

The material was then heated at 900°C in the absence of oxygen, burning off atoms such as hydrogen. This left behind carbon rods about half a millimetre tall. These carbon rods were then wired together to act as positive and negative terminals and the space between them infiltrated with lithium ions.

The advantage of the new battery design over more conventional designs is that they can generate larger bursts of energy because they use so many alternating terminals. Furthermore, the amount of current available can be controlled by controlling the number of rows of terminals that are wired together.

The current design was produced on a silicon substrate. However, the researchers know that this needs to be changed to a cheaper alternative before the new battery design can be economically viable.

Posted February 17^th, 2004