Narrowboat 400Ah lithium build — worth going Victron all the way or mix and match?

Finally pulling the trigger on replacing the tired AGM bank on my narrowboat. Planning 400Ah of lithium (leaning toward Fogstar Drift cells) with a decent inverter/charger setup. The question is whether to go full Victron ecosystem — MultiPlus-II, Cerbo GX, SmartSolar MPPT — or save a chunk of money mixing in some cheaper bits where it doesn't matter as much.

Full Victron would be around £2,200–2,500 just for the inverter/charger and monitoring. The integration via VE.Bus and VictronConnect is genuinely slick, especially for a liveaboard where you want to see everything in one place. But I'm wondering if a decent Renogy or Epever MPPT would do the same job for £150 instead of £400+ for a SmartSolar 100/30.

The Fogstar Drift 200Ah cells are looking good value — anyone running them on a boat with decent cycle data? Salt-damp environment is my main concern, plus the BMS talking nicely with whatever inverter I land on. I've read mixed things about getting third-party BMS units to play properly with the MultiPlus without a proper CAN/VE.Can connection.

Is the full Victron setup genuinely worth the premium for a narrowboat specifically, or is that mostly marketing? Real-world experience here would be useful rather than YouTube builds from people sponsored by the brands they're reviewing.

ChrisCampbell90 | 847 posts

@Spud79 great project! I did almost exactly this on my 57-footer last year. One thing worth considering with the mix-and-match route is CAN bus communication — if your BMS, charger, and MPPT are all talking the same language, charge profiles adjust automatically based on actual battery state rather than just voltage. Victron's ecosystem does this really well natively.

That said, I ran Fogstar Drift cells with a Victron Multiplus-II and Cerbo GX, but used a Daly Smart BMS bridged via a third-party cable. Works fine, just needed some fiddling in VictronConnect.

The honest answer is full Victron is slicker but genuinely expensive. Budget for the Cerbo regardless — having that monitoring on a narrowboat where you're away from shore power for weeks is worth every penny.

12VNerd | 1,243 posts

@Spud79 solid choice on the Fogstar Drift cells — cracking value for money. On the Victron question, I'd say the comms bus is what makes or breaks the decision. If you go full Victron (MultiPlus-II, SmartSolar, Cerbo GX), everything talks to each other via VE.Bus and VE.Direct properly — state of charge accuracy is genuinely impressive and you get proper DVCC control which matters a lot with lithium.

That said, a decent BMS like the Daly Smart or JK paired with a Victron inverter/charger still works well if budget's tight. Where I'd not skimp is the MultiPlus itself — on a liveaboard narrowboat you'll thank yourself constantly.

What's your charging setup like? Engine alternator, solar, shore power? That'll affect which compromises are actually worth making. 🛶

Barry1965 | 2,156 posts

@Spud79 good timing on this — I swapped out a tired AGM bank on my 62-footer about 18 months ago and went full Victron. The honest answer is the integration is genuinely worth the premium if you're living aboard or doing long cruises. The DVCC system with a compatible BMS means everything talks properly — charge sources, loads, the lot. Where people come unstuck mixing brands is usually the BMS communication side; you can end up with the inverter/charger not getting accurate state-of-charge data and behaving oddly.

That said, the Cerbo GX is where the real magic happens — monitoring everything from your phone while you're down the pub is rather lovely.

Main question I'd ask: what's your primary charging source? Engine alternator, shore power, solar? That shapes the whole system design more than the brand choice does.