An experimental battery created by researchers at the Fudan University in China is believed to be working at temperatures as low as -70oC, far colder than conventional lithium-ion batteries that lose 88% of their room temperature capacity at -40oC. This finding could help engineers develop technology suitable for extremely cold temperatures.
The team replaced conventional lithium-ion electrodes with organic polymers that do not rely on intercalation, which slows down as temperature drops, in order to tackle the below zero drop in performance and capacity. Then, they combined the electrodes with an ethyl acetate based electrolyte with a low freezing point and the result was a battery capable of conducting charge even at extremely low temperatures.
Compared to materials in conventional lithium-ion batteries, organic materials are abundant, inexpensive and environmentally friendly, said Xia, who estimated that the organic electrodes cost one-third of those in lithium-ion batteries.
The team claimed that the technique used has several advantages compared to simply tweaking lithium ion batteries, which require additional material. However, the researchers said they need to improve the batteryâs assembly process and its energy per mass before it is commercialised.