Actually the battery capacity in the 80/80x and 85/85x is the same LG battery. The main changes are the battery converter/controller and drive motors are new and more efficient versions and the cars software has been updated to version 4.0 (not backwards compatible with 80/80x variants)
See here, https://www.youtube.com/watch?v=s4X8w8sZ8xE
Please excuse spelling/typos. Apart from being a clot it turns out I had one on my cerebellum that's now causing various problems!