In terms of future work, a further factor that could be examined to alter the transition temperature is the oxygen site. This determination of the phase transition temperature via O site substitution has yet to be explored, although has been considered as potential room temperature cubic phase stabilisation prior 107 . However, assessment via Cl or F substitution with O on the phase transition temperature is complex, as high temperatures can easily remove the halogen dopant forming more thermodynamically stable by-products. Further correlative evidence could be found by investigating the transition temperature by changing the XO4 sites, this may yield further confirmation of the controlling factors, but would not necessarily aid in cubic Li7 phase formation