Author(s): Raghu Gopal
Last week, researchers at the University of California, Irvine announced a battery material using nanowires which they say can be recharged hundreds of thousands of times before needing to be replaced. This could greatly improve device lifespan and potentially mean hundreds of millions fewer batteries ending up in waste piles of electronic materials.
Most lithium-ion batteries used today have a very limited lifespan. Battery charging capacities degrade quickly over time, and few batteries last more than 7,000 recharges before being rendered useless. The method developed by researchers in California could mean batteries could handle up to 200,000 cycles without any loss of capacity or power.
The use of nanowires in batteries has long been on the cards. They are thousands of times thinner than a human hair yet are highly conductive and feature a large surface area for storage and transfer of electrons. However, nanowires are extremely fragile and don't hold up well to repeat discharges and recharges. In a typical lithium-ion battery, they expand and grow brittle, which leads to cracking.
The researchers have solved this problem by coating a gold nanowire in a manganese dioxide shell and encasing the assembly in an electrolyte made of a Plexiglas-like gel. Mya Le Thai, doctoral candidate at the University of California, Irvine, who is the lead author of the research, said the team did not detect any loss of capacity or power by using the technology in tests spanning over three months and 200,000 recharge cycles. The findings were also published in the American Chemical Society's Energy Letters.
The development is a positive step toward making longer-lasting batteries, though the use of gold, even in small quantities, is likely to make commercial development expensive. The researchers believe if the technology proves popular, gold could be replaced by a more common metal such as nickel.
The road from university lab work to a real-world product could be quite a long one, but this certainly is positive news. The ability to improve the performance of modern batteries is vital in industries as diverse as cars and computers. These electrolyte-boosted lithium-ion batteries are an innovative breakthrough, but further research will be needed before the technology can be commercially deployed.