go with LI+ (Score 1)

Lithium ion technology is something that is still fairly new to consumer products, but it has been around in the "experimental implementation" field for a long while.
the UMR Solar Miner III seen here can do close to 600 miles on a 68Kg LI+ battery pack, whereas a traditional lead-acid battery pack that would give us the same milage would be more than twice the weight