Huawei researchers recently unveiled what they said was the first long-lifespan graphene-assisted Li-ion battery able to withstand high temperatures. The announcement was made by Watt Laboratory, an organization under Huawei’s Central Research Institute, at the 57th Battery Symposium held in Japan.
Huawei’s research results show that new graphene-assisted heat-resistant technologies allow Li-ion batteries to remain functional in a 60 ˚C (140 ˚F) environment, a temperature 10 ˚C higher than the existing upper limit. The lifespan of the graphene-assisted Li-ion batteries will also be twice as long as ordinary Li-ion batteries.
Dr. Yangxing Li, Chief Scientist at Watt Laboratory, pointed out that three technologies contributed to the breakthrough in the graphene-assisted high-temperature Li-ion battery.
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 are used for the cathode, improving the thermal stability of the cathode powder.
Third, graphene allows for more efficient cooling of the Li-ion battery.
We have performed charging and discharging tests in a high-temperature environment. 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.—Dr. Li
Huawei’s research results can reshape the storage systems of communications base stations. In high-temperature regions, outdoor base stations powered by the graphene-assisted high-temperature Li-ion batteries can have working lifespans longer than four years. These batteries ensure a high mileage for electric vehicles per charge in high temperatures. They can also guarantee the safe operation of drones, which often generate a significant amount of heat.
At the 56th Battery Symposium also held in Japan in 2015, Huawei’s Watt Laboratory revealed its quick charging technology, which recharges 48% of a 3000mAh battery in just 5 minutes. According to Dr. Li, Huawei has commercialized the developed quick charging batteries and will announce a super-quick charging mobile phone in late December.