Sounds like you need to do some additional research. There are now OEM highway capable electric cars out there. They are definitnely liscensed for the road, there has to be a way for you to get yours on the road.
Also, it sounds like you're planning on using lead for the conversion? Lithium does cost a lot more, but also lasts much longer and is much lighter. You should take a look.
That being said, show us some pics and give us more info!
Welcome.