When we found our project sailboat dream-hull in a remote Southeast Alaska village, there was essentially no useful batteries and no electrical system installed. We had to determine what we wanted for batteries and then install them and build an electrical system around it.  The electrical items that Glacier Gem, our aluminum schooner, did have were limited to two large, unsecured batteries connected to a rusted-out and hotwired engine gauge panel. None of the gauges worked and there was no key. The giant batteries were best suited to a farm tractor or to a bulldozer than to a seagoing vessel.…

The increased use of lithium-ion chemistry batteries on land has had a parallel trend in the marine world. Lithium-ion batteries, which were considered highly exotic five years ago, are becoming ever more commonplace on voyaging boats. What are the reasons for this trend and how widespread is it? The longtime king of marine batteries, of course, is the lead acid cell. Using a liquid electrolyte and lead plates, each of which is a matrix generally filled with soft lead, the wet cell marine battery ruled supreme for its stability and its storage capacity. Different types of wet cell units were…