Given some newsworthy stories, you might be wondering – is putting a lithium battery in a boat a good idea? Although lithium batteries have been known to explode or catch fire, we’ve been traveling around with lithium battery banks in our RV’s for almost a decade with no problems. Not only that, but we’ve put them in over two hundred RV’s for clients, and none of those batteries have caused any safety concerns either.
Lithium batteries after being submerged for 2 days
In September 2024, Hurricane Helene struck Florida’s west coast. During the storm, a client’s RV was stored at McDill Airforce Base, which measured record-breaking storm surges of over 7.5 feet.
The client’s RV, a large fifth wheel, was partially submerged in brackish water for over two days – including his 920Ah lithium battery bank.
We advised the client to ensure the entire system was turned off, including the batteries (the Epoch batteries can be powered off individually).
After working with his insurance on other water damage repairs, the RV was ready to be transported to our shop so we could provide an estimate of solar system repair costs. When he arrived at our shop, he lowered the jacks which support the fifth wheel before disconnecting his truck. When Tom opened the battery bay, he discovered that one of the Epoch 460Ah batteries that had been submerged was connected, on, and powering the leveling jacks!
Not only was the battery powering the jacks, but also the rest of the 12VDC system, and even the air conditioner on the 120VAC system via the inverter! The Epoch app showed the battery charging and it reached 100% SoC. Thankfully the remainder of the system components had been installed in an upper bay, and the waterline stopped just beneath it.
Waterproof Lithium Battery Still Works!
The Epoch 460Ah battery held to its IP 67 waterproof rating, with only the terminals having any damage.
The terminals and lugs were extremely corroded due to the prolonged contact with brackish water, and broke apart with very little force.
Lithium Batteries for our Loop Boat
Given our personal and professional experience with lithium batteries, we feel entirely comfortable putting them in our Loop boat. We plan to stay on the hook (or boondock for our RVer friends) as often as possible, both to save money and to immerse ourselves in the natural and man-made beauty of our waterways.
When we purchased our boat, it came with three batteries – one for cranking the generator, and one each for cranking the port and starboard engines. A Perko battery selector switch combined the engine batteries together to provide power to the “house.” Between the Group 27 AGM (Absorbant Glass Mat) battery for the port engine, and the Group 24 FLA (Flooded Lead Acid) battery for the starboard engine, we had ~100Ah usable house battery bank. That’s definitely not enough to power our adventures for the next year! We’re currently in the process of upgrading all our batteries from the lead-acid technology to all lithium battery technology.
House Battery Bank
Epoch 460Ah Lithium Battery
For our lithium house battery bank, we chose to go with two of the batteries we know with certainty are 100% waterproof: the Epoch 12V 460Ah Elite Series battery. We’ll be increasing our house battery bank from 100Ah to 920Ah, or as we like to think about it, from 1,200Wh to almost 12,000Wh.
The Epoch 460Ah meets the American Boat and Yacht Council’s (ABYC) standards – it’s UL certified, it has a battery management system (BMS) which will alarm audibly before shutting down. In addition, the battery is IP 67 waterproof rated, has built-in Bluetooth, and built-in heaters. It also has built-in Victron Energy communication ports to connect directly into a Victron Energy system, like the one Tom is installing on our boat.
This battery bank will be separate from our cranking batteries, although we’ll be able to connect them together if our cranking batteries fail.
Lithium Cranking Batteries in our Boat
Epoch 120AH Lithium Battery
For our cranking batteries we chose to go with two of the Epoch 12V 120Ah Pro Series Dual Purpose battery, for a total of 240Ah total. This battery bank will crank our generator and both our diesel Yanmar engines.
Each battery has 1,100 CCA (cold cranking amps), and is also IP 67 waterproof rated, UL certified, heated, and Bluetooth capable. These batteries also have built-in BMS and Victron comms, like the Epoch 460Ah.
We’re very excited to use our system, collect data, and report back to you! This article is not sponsored – if you plan to purchase Epoch Batteries, please consider using our affiliate links to make your purchase.
Check out the full list of solar system components we’re installing in our yach on our previous article here.
