On our last trip to the boat, we opened the sliding glass door and were greeted with the acrid odor of rotten eggs. A frantic search for the source revealed that we had an overcharged lead acid battery that was boiling and putting off hydrogen gas, a very dangerous situation (think Hindenberg). We quickly disconnected the bad battery, let it cool down and vented the cabin. Fortunately, since the house battery bank is hooked up in parallel, we were still able to get 12 volts for the rest of the trip, but it did prompt us to replace our lead acid batteries with sealed maintenance-free batteries. We had been planning to do this for a long time but had never gotten around to it. Now that the old batteries had gone bad, the time had come.

Acid Spill

Leaking Battery

Cindy researched our new batteries and we settled on Lifeline GPL-8DA 255 Amp-Hour Absorbed Glass Matrix (AGM) batteries for the boat’s house bank. AGM batteries use fiberglass mats to hold the electrolyte in contact with the lead plates.

The first step was to remove the old batteries and battery boxes from under the bunk in the guest cabin. One issue was that the old batteries did not have any handles on them and each of the three large house batteries weighed around 90 lbs. Add to that the fact that the batteries were a tight fit in their boxes, leaving you with no room to get a grip on the battery and the boxes were screwed to the floorboard. We solved this dilemma by getting a pair of shears and cutting away the sides of the plastic battery boxes so I could get a better grip on the batteries.

Cindy Cutting

Cutting Up Old Battery Boxes

Getting the batteries out just required brute force. I grabbed them by the sides and lifted them out of the compartment underneath the bunk (trying to use my legs as much as possible), then we wrapped straps around them and carried them in tandem out of the boat and onto the dock in stages…out of the compartment, up each individual step on the stairway into the salon, out into the cockpit, up onto the deck and out onto the dock.

Manhandling the Batteries

Manhandling The Batteries

With the old batteries out, Cindy pulled out the remains of the old battery boxes and installed the new ones while I recruited a helper from the marina (the folks who run Jekyll Harbor Marina are fantastic!) to get our 600 lbs of new batteries from the office (where we had them drop-shipped) down to the boat. Fortunately the tide was in so the gangway from shore to the dock was nearly level (at low tide the gangway is at almost a 45 degree angle…a steep angle when trying to control a cart with 600 lbs on it). The new AGM house batteries came equipped with rope handles on the sides since each battery weight 160 lbs, which made moving the batteries from the dock down into guest cabin a lot easier (well, less than impossible). After we manhandled all three house batteries onto the boat and down into the bunk compartment we toasted our success by drinking an ice cold Landshark.

The new batteries fit like a glove into the new boxes and we’re looking forward to many years of clean-smelling, maintenance-free performance out of them.

New Batteries

New House Battery Bank