There's an article on CNET about a new battery tech from Toyota that can recharge 3x faster than today's typical cells, and is supposed to retain at least 90% after 5000 cycles, or over 14-years at a daily recharge cycle. They plan to market it on one or more of their vehicles in 2019. Others have tried, and have had issues with reliability and reproducibility. We'll see how Toyota fairs with theirs. This could be a game changer.
On a different subject, the area rep at my dealer said that the electric X3 will have about 400-miles of range when it shows up in about a year. No idea, yet, if it will have a REx option.
2011 535i x-drive GT, 2014 i3 BEV