We Built Our Own Lithium Battery Bank (And It Was Way Harder Than Expected) Ep.71 #sailboatrefit

After years of planning, researching, sourcing parts, and redesigning, we're finally building one of the most important systems on ROAM: our DIY lithium house battery bank. Instead of purchasing pre-packaged marine batteries, we imported individual 2.3-volt lithium cells directly from China and built the entire system ourselves. Why? Two reasons: cost and space. By building our own batteries, we saved approximately $40,000 compared to equivalent marine battery systems. Just as importantly, we were able to dramatically increase our energy storage density within the limited space available aboard the boat. More power, less space, and a lot more work. Our final design consists of: 🔋 Four 48-volt batteries for the primary house bank 🔋 Two 24-volt batteries for equipment not available in 48 volts ⚡ Enough stored energy to support our goal of comfortable off-grid cruising Building the bank turned out to be far more involved than simply stacking cells together. We started by constructing a custom battery box to provide a perfectly flat and level foundation. We added anti-arc protection, a Mylar isolation layer to reduce friction, and developed a somewhat unconventional tie-down system designed to keep the cells secure even in extreme conditions. Along the way, we faced plenty of challenges. Finding room for the BMS units, bus bars, contactors, fuses, and cabling while maintaining a clean layout proved harder than expected. After changing the cell arrangement partway through the build, we had to purchase new BMS sense wires and rethink portions of the installation. The result isn't quite as tidy as we'd envisioned, but it's safe, functional, and delivers exactly what we set out to achieve. Like many parts of this refit, it's a system we'll continue refining as we move closer to launch. If you're interested in: DIY lithium batteries Victron energy systems Off-grid power systems Sailboat electrical upgrades Catamaran refits Marine electrical design Liveaboard cruising preparation ...this episode is packed with practical lessons, problem-solving, and real-world DIY boat work. After years of planning, it's incredibly satisfying to finally see our power system taking shape. ⛵ One step closer to sailing. 00:00 Everyone asks us why 00:10 Channel intro 00:26 Battery box 04:51 Arc protection 06:52 Tie down system 09:50 BMS 11:38 Fuses, bus bars, and contactors 14:29 What do we have and why 16:58 Why did we do this and does it work 18:46 Like and subscribe 19:06 End Card ☝More about us, our adventures, and how we do all this on our website.More about Roam here ⛵️https://sailingroam.com/our-sailboat/ 📲 Keep up with us on social FACEBOOK: https://facebook.com/sgsailingroam INSTAGRAM: https://instagram.com/sailing_roam ----------------------------------------------------------- WE'RE GERI AND SHAWN. A couple travelers out chasing the horizon, meeting the people, and capturing it to share with you. We’ve chosen to Roam the world by boat because, let’s face it, the most interesting path is rarely a straight line. As we learn to let go of our American drive to finish, and embrace the meandering routes across islands, oceans, continents, and people, we hope to gain a better sense of our world and our place in it. The path won’t always be comfortable or easy to find but, it will always #roam #DIYLithiumBattery #BoatElectricalSystem #VictronEnergy #OffGridPower #SailboatRefit #CatamaranRefit #MarineElectrical #DIYBoat #LithiumBatteryBank #LiveaboardLife #CruisingLife #SailingLife