Researchers at Huawei’s Watt Laboratory have unveiled a graphene-assisted Li-ion battery that can withstand high temperatures and offers a long lifespan.
According to the researchers, their new technology allows Li-ion batteries to function at temperatures up to 60˚ C (140˚ F), 10˚ C higher than the current upper limit. The lifespan of the graphene-assisted batteries is expected to be twice as long as that of existing designs.
Dr. Yangxing Li, Chief Scientist at Watt Laboratory, pointed out that three technologies contributed to the breakthrough. First, a special additive in the electrolytes can remove trace water and prevent the electrolytes from decomposition in high temperatures. Second, modified large-crystal NMC materials improve the thermal stability of the cathode powder. Third, graphene allows for more efficient cooling.
“We have performed charging and discharging tests in a high-temperature environment,” said Dr. Li. “The tests show that when working parameters are the same, the graphene-assisted high-temperature Li-ion battery is 5° C cooler than ordinary Li-ion batteries. Over 70% of the graphene-assisted battery’s capacity is left after it is recharged 2,000 times at a temperature of 60° C. Less than 13% of its capacity is lost after being kept in a 60° C environment for 200 days.”