Recently, the development of hybrid and electrical vehicles and energy storage devices has raised the requirement on high–rate ability, safety and cyclability of lithium ion batteries. Use of carefully structured nanosized electrode materials is an effective approach to improve the high–rate ability.
The AU battery activities focus on nanosized materials, and battery materials are synthesized with different size, shape, crystallinity, surface chemistry and aggregation structure by an environmentally friendly supercritical hydrothermal method. We study the influence of the different reaction conditions on nucleation and crystallization mechanisms of nano crystals in hydrothermal synthesis in real time by means of in situ synchrotron X-ray diffraction techniques. Using a fully equipped laboratory for assembling “coin cell” Li-ion batteries, we perform systematic studies of the relationship between particle size, crystallinity and battery performance, with the aim of finding and understanding the optimum size and crystallinity regime for practical operation.
New efforts concerns in situ PXRD studies of structural changes in the battery materials during lithiation/delithiation cycling. In this talk, I will focus on our study on the relationship between particle size, crystallinity and battery performance of the nanosized Li4Ti5O12 anode materials.