Our boat has “some of the best” batteries. Luna Sea came with two Lifeline 210amp hour batteries.  Don’t worry, we didn’t really know what that meant either.  Turns out that is a fantastic brand of AGM batteries.  They are much more forgiving to being over-used than typical boat batteries.  This results in a longer lifespan than less expensive batteries – so you may end up saving money in the long run.  The current batteries have done everything we’ve asked them to do, thus far.  But we’ve been at a dock for 3 years with unlimited shore power – so we haven’t asked … Continue reading Upgrading the Batteries: Lithium Ion on a Sailboat