New method may lead to more powerful and durable batteries for EVs
Nissan Motor Company and Japan’s top universities along with affiliate Nissan Arc Ltd. announced the world’s first analysis method that allows them to ‘directly observe the electron activity in the cathode material of lithium ion batteries during charging and discharging.’
Using this newly-discovered analysis technique during the use of current batteries and their future development will let Nissan researchers gain precious data and information that may help them manufacture higher-capacity and more durable batteries that may lengthen the driving distance of electric vehicles.
Tokyo University, Kyoto University and Osaka Prefecture University were educational institutions tapped by Nissan Arc, a subsidiary of Nissan Motor Company, in a joint R&D effort.
"Creating this analysis technique was a major step toward the further development of high-capacity, next-generation lithium ion batteries. It will play an important part in our future R&D aimed at extending the driving range of future zero emission vehicles," said Takao Asami, Nissan senior vice president and president of Nissan Arc Ltd.
The problem facing current battery technology is the inability to get an accurate reading of the electron activity inside the battery. The newly developed analysis technique combines x-ray absorption spectroscopy that utilizes L-absorption edges and the first principle calculation from Japan's Earth Simulator supercomputer.
Using x-ray absorption spectroscopy with L-absorption edges, observation of electrons that were directly involved with the cell reaction can now be accomplished. Accurate analysis of the amount of electron mobility is made possible by combining the observation results with first principle calculations from the Earth Simulator supercomputer.
Nissan Arc has used the new analysis technique to investigate lithium-rich high-capacity electrode materials, which are considered promising agents to increase energy density by 150 percent. The analysis revealed that at a high potential state, electrons originating from oxygen were active during charging. Meanwhile, electrons that originated from manganese were observed to be active during the discharge reaction. These findings were a big step forward toward the commercial development of lithium-rich electrode materials, which can produce higher-capacity, long-lasting batteries.