New Silicon Anode Design for BatteriesCategory: Science & Technology
Posted: February 19, 2013 12:26PM
In this technological age it is a fact of life that batteries are everywhere, and that will only become more true as more advanced technologies are developed. Modern batteries are somewhat limiting though with the time it takes to charge them and how much energy they can actually hold. Researchers at the University of Southern California however have found a new battery design that will greatly accelerate charging and increase capacity, potentially at low cost.
For some time researchers have been trying to replace graphite electrodes in lithium-ion batteries with silicon, because silicon can store more energy and charge more quickly. Unfortunately silicon is also relatively fragile, so eventually it will break as it absorbs the lithium ions and swells up. The USC researchers have been looking at silicon nanowires, which better survive the swelling, but they are difficult and therefore expensive to manufacture. Recently though they have decided to try more easily produced silicon nanoparticles, which were processed like the nanowires to contain pores to absorb more ions, more quickly.
With the silicon nanoparticles as the anode, the researchers created a battery that can store three times as much energy as a similar graphite-based battery and recharge in just 10 minutes. The new battery is not perfect though as it only survived 200 charge-discharge cycles, compared to the 500 of graphite batteries. However, the researchers' nanowire batteries were able to survive 2000 cycles, so they are confident they can improve the nanoparticles to compete with modern batteries.