Researches using x-ray imaging techniques have discovered why a cathode material in lithium-ion batteries is capable of reaching high voltages.
Using images combined with data analysis algorithms the teams explored the mechanical properties of LNMO spinel (composed of lithium, nickel, manganese and oxygen atoms) at the nanoscale level.
The insights into how the cathode material behaves while the battery charges were published in the journal Science.
Analyses of the images revealed that the defects are stationary when the battery is at rest, but when the battery is charged to high voltage, the defects move around within the cathode material.
While the cathode materials in most of today’s lithium-ion batteries operate at 4.2 Volts maximum, the LNMO spinel functions at up to 4.9 Volts.
The multi-institutional team was led by physicists and nanoengineers from the University of California. The X-ray imaging experiments were completed at Argonne National Laboratory’s Advanced Photon Source.
The study could lead to understanding how other battery materials can work at higher voltages for use in high-power applications such as electric cars, said Andrew Ulvestad, the first author of the Science paper.
Shirley Meng, nanoengineering professor in the UC San Diego Jacobs School of Engineering and a corresponding author on the study, said the study points to the possibility of ‘defect engineering’ for battery materials.
