Lithium ion batteries with typical liquid electrolytes, suffer from safety issues caused by the flammable liquid. All-solid-state batteries with a thin incombustible inorganic solid electrolyte represent an alternative technology providing higher safety. However, typical storage materials undergo a volume change and normally sintered composite cathodes do not provide enough strain tolerance to allow this expansion without inducing large stresses causing failure of the cell. To address these problems target at the following scientific aims:
Understanding the theoretical basis for the stress development considering anisotropic material properties, phase changes during de-/lithiation (which are rather pronounced for typical storage materials) and the transient behaviour (influence of charging speed).
Create new microstructural designs including new ideas, such as fibre mats and polymeric conductors with low stiffness with potentially larger strain tolerance.
Measure the necessary material parameters.
Experimental measurements of the actual damage of manufactured (original and improved) cells.