After several years of experimentation, Kang and Ceder discovered that the problem could be alleviated by fabricating groove-like structures spaced just 5 nanometers apart on the surface of the lithium iron phosphate material. The resulting material accelerated the transport of the ions by as much as 36 times.
"With our surface treatment, the recharging of batteries is no longer limited by ion transport, which means that not only will batteries recharge more quickly, but they can also deliver power more quickly than before," Kang said.
Recharging batteries for cellphones and other small devices using the technology would take seconds, the researchers claimed. For the emerging electric car industry, electric cars would be able to accelerate as quickly as gas-powered vehicles.
While the recharging technology could be integrated into the existing battery infrastructure in two years, home rechargers for electric cars would have to be redesigned to handle the rapid transfer of energy. "For cars, the speed that they can recharge at home will be limited not by the battery but by how much power can be made available to homeowners through the [electric] grid," said Kang.
Tests so far show that the nanoscale surface treatment for lithium iron phosphate is as durable as the bulk material, allowing repeated quick charging and discharging without degradation.
Funding for the MIT research was provided by the National Science Foundation, the Materials Research Science and Engineering Center and the Energy Department's Batteries for Advanced Transportation Program.