Engineering news
Nanowire based batteries could be the key to creating permanent batteries that do not require replacement, a study has found.
Researchers at the University of California, Irvine, found that using highly conductive nanowires could lead to batteries with longer a lifecycle to power cars, spacecraft and personal electronic devices, as the material could be recharged hundreds of thousands of times.
In a test, the scientists were able to charge and discharge, or cycle, an electrode up to 200,000 times over three months. Results showed that the capacity of the material did not diminish and the filament did not crack.
Nanowires, which are a thousand times thinner than the width of human hair, are usually susceptible to fracture when they are repeatedly cycled. In a lithium-ion battery, the filaments will expand, grow brittle and eventually crack. To counter this issue, the study leader and UCI doctoral candidate Mya Le Thai used a manganese dioxide shell to coat the gold nanowires and encased the model in an electrolyte gel made from a thermoplastic substance.
The researchers believe that gel plasticised the metal oxide in the battery, making it more flexible and able to expand and contract. Reginald Penner, senior author on the study, said: “Just by using this gel, you could cycle it hundreds of thousands of times without losing any capacity. These things typically die in dramatic fashion after 5,000 to 7,000 cycles at most.”
Thai said: “The coated electrode holds its shape much better, making it a more reliable option. This research proves that a nanowire-based battery electrode can have a long lifetime and that we can make these kinds of batteries a reality."