Scientists of the Novosibirsk State Technical University NETI have created a laboratory installation for testing lithium batteries (LIA) for electric vehicles in order to determine the degradation resistance of batteries. The research is aimed at developing measures to increase the battery life.
"The stand we have created allows cycling up to 30 battery cells at the same time. The battery operation is divided into hundreds of cycles; by observing each of them we can analyze how the LIA parameters change, and therefore adjust their resource according to various conditions, " said Alexander Shtang, Associate Professor, Department of Electrotechnical Units. During the operation of an electric vehicle, LIAs are subjected to specific loads and stress factors, such as: rapid load build-up in the mode of intensive acceleration, change of the discharge to a charge mode during recuperation, short repeated cycles of driving a car in heavy traffic. Identifying primary causes of battery degradation will help prolong their life-cycles, as well as make an electric car more appealing for consumers and facilitate the advent of electric transport era.
In the near future, the scientists are to use the created installation for conducting a large-scale full factor experiment, with all the necessary parameters and results recorded, described, compared and analyzed. After that, the batteries will be sent to the Institute of Solid State Chemistry and Mechanochemistry (ISSCM) SB RAS, where its scientists will identify the changes and violations in the chemical structure of the LIA. Based on the data obtained, the scientists would find out what they can do to prolong the service life of such batteries.
Researchers have already identified a number of factors that directly affect the battery life, such as the growth rate of current loads, the nature of recuperation modes, and the battery relaxation time.
Besides ISSCM SB RAS, the project involves scientists from Harbin University of Science and Technology. Using a thermal camera they will conduct experiments on battery service life under the thermal influence, which is essential for using electric vehicles in countries with the harsh climate, especially in Siberia. The project is supported by a two-year RFBR-GFEN grant, ending in 2021.