Vehicle battery packs will obviously standardise, technology pretty much always does (VHS tapes is an obvious example). Fledgling battery pack standards will rapidly emerge as vehicle and battery manufacturers work together. These standards will merge, harden and rationalise.
I don't need to look up the dangers of charged batteries (I previously designed portable electronic equipment for use in the nuclear industry). While I agree that batteries certainly can be dangerous items, I find it hard to think of them as less safe than handling and storing large volumes of petrol. Most battery incidents are caused by poor manufacturing processes, not from an intrinsic problem. But, like petrol, careless handling will always present a threat.
Nothing wrong with nuclear power... its pretty much the cleanest and most reliable thing available that can plug the gap from where we are now to where we need to be by 2040 (say, a 5 to 10GW increase in generating capacity?). But I really do doubt our government's willingness to invest in a new generation of nuclear plants and/or the UK public wanting such a high proportion of their taxes being spent on this area (unfair to blame governments for everything, it's the ordinary people like us who vote for them).
2040 isn't that many decades away...