Scientist unwittingly stumbles on technique to elongate battery life to 2,00,000 charge cycles

Nanowire batteries are an experimental battery technology that increases power storage density, faster charging and higher power delivery. Nanowire batteries use a cluster of tiny filamentous structures thousands of time thinner than the human hair. This increases the surface area in contact with the electrolyte. These batteries are not yet used in commercial products yet because the nanowires are susceptible to damage. Every time the nanowire batteries are recharged, the nanowires tend to deteriorate and break. Researchers at University of California, Irvine playing around with nanowires and gels accidentally tested a technique that can increase battery life to well beyond the lifespan of a product.

Gold nanowires were encased in a manganese dioxide shell, and immersed in a plexiglass like gel based electrolyte. The gel based electrolyte was just supposed to work as an alternative to a liquid electrolyte, but had the additional benefit of insulating the gold nanowires from structural damage on repeated use. The gell plasticized the gold, making it more flexible, and prevented it from developing cracks. The resulting battery prototype was tested for 2,00,000 charge cycles. For comparison, commercially available Li-Ion batteries last for around 5000 charge cycles.

The downside of making this technology commercially available and for use in smartphone batteries, is the high cost of the gold wires involved. Although the amount of gold is very little, the cost is still more than conventional batteries. It may be possible to replace gold with another metal, but this might compromise the number of charge cycles the battery can bear. The technology can also be used for electric vehicles, spacecraft and appliances.