Someday soon, I am hoping ,that Lead acid batteries won't be the most popular choice for powering electric cars, but right now they are the choice of most. Cost is a big factor and they are relatively affordable right now. They are also almost entirely recyclable. Bonus!
On the downside they are heavy, which reduces range and causes problems with the suspension, even though my motor now only weighs 80 pounds and there is no gas or tank to carry in the back. Still, I probably added 1000 pounds to my bus in all. Some day I'll have it weighed.
There is a brand of batteries called Trojan which are supposed to be the best, but they cost almost twice as much as mine, and like I said I really am hoping for a breakthrough in battery technology withing 4 years (the life span of a lead acid battery).
While my batteries are working I have had an issue with the connections coming loose and causing enough heat to melt the lead side post style connectors I used. I fixed this with lock washers though and haven't had any problems since. Other style batteries have better connections than mine, so I would look into this if I was starting anew, but again, the price was right.