The new Ballistic Batteries are unbelievable. That's why I've become a dealer. I was just looking for a way to develop a super strong water tight case and found these. They now come with a balance charger plug and I will be selling the special balance chargers. Since they will hold their voltage for up to a year, these chargers are just for maintaining perfect cell voltage. (Theoretical lifespan of over 10 years for a battery when the cells are balanced.) As long as you have no parasitic drain (other than the fan coming on for a few minutes) I would not hesitate to go on a RTW trip with one.