Lithium Ion batteries to yield longer recharge times
- — 10 April, 2007 16:30
The commonly-used Lithium Ion (Li-ion) battery of today is undergoing a facelift that researchers expect will deliver more usage between charges, and shorter charge/discharge times, to mobile consumers within the next five years.
Based on a process called 'nanostructuring', the new batteries will be built in very small sizes - measurable in nanometres - to shorten the distance between electrodes on either end of a Li-ion battery.
Conventional batteries produce electrical charge when Li-ions travel from an anode at one end of the battery, to a cathode at the other end. The power that is delivered by the battery, as well as the speed with which the battery is charged, is determined by the speed with which the ions can travel within the material.
By nanostructuring the electrode particles, researchers are reducing the ions' travel by a factor of a thousand.
"A nano-structured battery operates exactly the same as a conventional battery," explained researcher Marnix Wagemaker, an applied scientist at the Delft University of Technology in the Netherlands, "only the electrode materials (anode and cathode) are built up from nano-sized particles, whereas in conventional batteries the particle sizes are in the order of micrometers."
Besides speeding up the charge/discharge time, nanostructuring also enables battery materials to store higher amounts of Li-ions, which leads to an increase in energy density, allowing batteries to lasts longer between charges, the researchers say.
Wagemaker expects nanostructured batteries to find initial uses in applications with high power requirements, such as in batteries for hybrid or electric vehicles, noting that the extended battery life of nanostructured batteries will also be useful wherever Li-ion batteries are currently used.
"The consumer will profit from a higher energy density - your mobile phone will last longer - and higher power density, [which means] shorter charge/discharge times," he said.
Currently, researchers are working towards improving the stability of nanostructured materials to overcome problems with the lifespan of nanostructured batteries.
"As always, advantages are accompanied by disadvantages," Wagemaker said. "You can charge it [nanostructured batteries] not as many times as current batteries, but I strongly believe these issues will be solved."