Time for Lithium?Lead-acid batteries are so 20th century; lithium’s the future for your boats. Lithium batteries perform better and last longer than many lead-acid batteries. They weigh less and take up less room. They can provide a higher percentage of nominal capacity than lead-acid batteries, without shortening their life. They maintain voltage through almost all the discharge cycle. They can be recharged much faster. And their only downside is initial cost, but that’s more than offset by their increased lifespan. The higher cost, by the way, may make skippers replacing lead-acid batteries stop and think, especially if they don’t plan on keeping their boats for enough years to enjoy lithium longevity. But for folks building or buying a new boat, the extra bucks are negligible, especially if they spend lots of time at anchor. The difference is in the electrolyte. Lithium-ion batteries, which are used to power phones, tablets and other portable electronics, use lithium-cobalt-oxide (LiCoO), which provides lots of energy versus size and weight. You probably have one of these batteries in your pocket right now. Only thing is, cobalt is unstable, so if charged improperly, this type of lithium-ion battery can get hot and catch fire—not the kind of thing you want on board. Lithium-iron batteries, on the other hand, use a lithium-iron-phosphate (LiFePO) electrolyte that’s more stable, not combustible and can better resist mishandling during charging and discharging. It’s a trifle less energy dense than its cobalt-based cousin, but it’s also less expensive. Lithium-iron batteries can last for thousands of discharge/charge cycles—three, four, maybe five times as many as lead-acid batteries. The batteries discussed here are lithium iron phosphate, and they’re fine for installing aboard boats. Time for Lithium? I think we’ll be seeing systems like our GeePower's Li-ion batteries on a lot more boats before too long, especially cruising boats for folks who like to anchor out but don’t want to deal with a genset. Ah yes, lithium—the battery of the future, available today.