Unreveilling the correlation between phase transformation and capacity fading in commercial high voltage pouch cells through high resolution

High voltage LNO are the most promising candidates for commercialization, due to their high mass-specific energy density, high operating voltages and initial high capacity. However, during delithiation at high voltage, these materials presents phase reactions involving large volume changes, which cause cracks and capacity fade. O2 release from the material surfaces and a substantial loss of energy density whilst also reduces the order of the structure. To elucidate the degradative pathways occurring during the first few cycles of high voltage LNO electrodes, we propose in situ and operando X-ray diffraction commercial pouch cells to correlate the lattice distortion and phase transformation to the state-of-charge of the battery. Due to the rectangular geometry of commercial pouch cells, we will perform spatially resolve X-ray diffraction while cycling, using a multi-channel collimator, which allows to selected gauge volume and to perform high resolution X-ray diffraction analysis.