Living Off-Grid: Our Boat’s 30kWh Lithium Battery Setup
When we bought Tangaroa, our 78-foot aluminum yacht, the electrical system was a mess. Multiple battery banks, old inverters, and even exploding lead-acid batteries made one thing very clear: if we were going to live aboard full-time, we needed a reliable, powerful, and safe energy system.
That’s when I decided to build a massive lithium battery bank from scratch. Using 56 lithium iron phosphate (LiFePO4) cells I sourced directly from Alibaba, plus six large solar panels, we created an off-grid power system that runs everything on board—fridges, oven, stove, computers—just like a house.
Four years later, here’s how it’s held up.
The Old Power System Was a Nightmare
When we first got the boat, she had three separate battery banks:
- A 12V house bank under the forward locker
- The engine start batteries in the engine room
- A 24V bank on the aft deck for the windlass
Each one powered different systems, and nothing talked to each other. To make matters worse, just before leaving Alaska, one of the “new” lead-acid batteries exploded in the engine room. Later, our house bank started bubbling hydrogen gas and filled the boat with the smell of rotten eggs. Not only was this unsafe, but it also proved the system was unreliable.
We had to run our generator 24/7 just to keep the boat alive. Clearly, this wasn’t going to work for long-term living aboard.
Why We Chose Lithium Iron Phosphate (LiFePO4)
After researching options—lead-acid, gel cells, carbon pile—I settled on lithium iron phosphate batteries. The advantages were too good to ignore:
- More power density (lighter and more compact than lead-acid)
- Longer lifespan (3,000–5,000 cycles vs. 500 for lead-acid)
- Faster charging (can safely accept hundreds of amps)
- Lower long-term cost despite the higher upfront investment
We settled on a 30kWh lithium battery bank, giving us enough power to run the entire boat for two days without charging.
Sourcing 56 Lithium Cells from Alibaba
Instead of going with “plug-and-play” lithium batteries (Battle Born, Renogy, Victron), I went the DIY route. I chose CALB (China Aviation Lithium Battery) cells, well-known in the industry for reliability.
Each cell cost about $120 (in 2020), and shipping them took weeks—literally the slow boat from China. But at 56 cells, it gave us enormous capacity for the price.
To manage them, I installed an Orion BMS2 battery management system, custom bus bars, and a Gigavac GX110 contactor capable of handling over 1,000 amps continuously. In short, this setup could even start our Detroit Diesel engines without breaking a sweat.
Adding Six Solar Panels
To keep the lithium bank charged, we installed six Canadian Solar 395W rigid panels. Mounted on rail systems for airflow, these panels provide reliable charging in summer and reduce generator use dramatically.
We paired them with a Victron MPPT charge controller and Victron inverters, giving us seamless integration, remote monitoring via phone, and even the ability to auto-start the generator if needed.
In summer, the solar panels easily handle all of our daily loads. In winter, with low sun in Canada, we still need to run the generator—but usually just an hour or two a day.
Challenges We Faced With Lithium on a Boat
Of course, there are downsides. Here are the biggest ones we’ve experienced:
- Cold weather charging: Lithium batteries can’t charge below freezing. One winter, the engine room dropped too low, and the bank refused to accept charge until we warmed it with running engines and blankets. Eventually, we moved the batteries into the warmer pilothouse.
- Complexity: A DIY lithium system isn’t plug-and-play. It requires wiring knowledge, programming, and redundancy. Not everyone will want to take this route.
- Upfront cost: Between the cells, BMS, inverters, contactors, and fuses, the initial investment is steep. But compared to replacing lead-acid banks multiple times, it pays off long-term.
Living Off-Grid With Lithium Power
Now, four years later, we can confidently say this was the best upgrade we’ve ever made on Tangaroa.
- We can run everything—oven, welder, heating blankets, watermaker—without worrying about power.
- The system integrates seamlessly with solar, Victron gear, and our onboard electronics.
- In summer, we often don’t need the generator at all. In winter, we use it sparingly.
This lithium battery bank turned Tangaroa into a truly off-grid yacht. Quiet, reliable, and powerful.
The Stigma of Lithium Batteries on Boats
Whenever we share our system, the same comments come up: “Lithium batteries are dangerous. You’re going to burn your boat down.”
The truth is, our LiFePO4 (lithium iron phosphate) cells are far more stable than the lithium-polymer cells used in cars or laptops. They don’t have the same thermal runaway risks and are far safer when managed with a proper BMS.
We’ve lived with them for four years, full-time, without a single fire, meltdown, or serious issue.
Final Thoughts
Building a 30kWh lithium battery bank with solar power was a huge project, but it’s transformed how we live aboard our 78ft yacht. It was expensive and complex, but the payoff is absolute freedom: no need for marinas, no need to run the generator all day, and true independence.
Would I do it again? In a heartbeat.
If you’re considering upgrading your boat to lithium, don’t let the fear hold you back. Done right, it’s the most reliable and rewarding investment you can make for off-grid life afloat.
If you want to check out the video about our lithium build, click on the photo above or subscribe to our YouTube Channel. See you there!
Blaine
