Anyone else running LiFePO4 on a narrowboat? Sharing my setup and looking for advice on shore power charging

I've just finished installing a 200Ah LiFePO4 battery bank on my 57ft narrowboat and I'm fairly happy with how it's gone, but I've hit a couple of snags I wasn't expecting. Running two 175W solar panels on the cabin roof feeding into a Victron SmartSolar 100/30 MPPT, which works a treat when there's decent light. The problem is the marina shore power situation — I've got a 240V hookup available on my mooring and I'm trying to work out the best way to charge from it without cooking the batteries.

At the moment I'm using an old 30A lead-acid charger that came with the boat and I know that's not ideal for lithium. It doesn't have a proper LiFePO4 profile and I'm not confident it's respecting the 14.6V absorption voltage correctly. I've been watching it on the Victron app and the readings look a bit all over the place. I'm thinking a Victron Blue Smart IP22 or maybe a Phoenix charger, but I'm not sure which size to go for given the 200Ah bank.

Has anyone integrated shore power charging alongside solar on a narrowboat specifically? I'd love to know how you've handled the two charging sources at once — does the Victron MPPT and a mains charger play nicely together into the same bank, or do you need to be more careful about it? Also curious whether anyone's bothered with a Victron Cerbo GX for monitoring everything in one place, or if that feels like overkill for a modest setup like mine.

Wardy16 | ⭐ Regular Member | Posts: 847

@CallumReid nice one, 200Ah LiFePO4 on a narrowboat is a solid setup! I ran something similar on my 60ft trad stern for a couple of years before upgrading.

What charger are you using for shore power? That's usually where people come unstuck with lithiums on boats - a lot of marina hookup chargers are set up for AGM profiles and will either undercharge or, worse, keep pushing voltage when the BMS cuts out and throw a fault.

Worth looking at a Victron IP22 or similar if you haven't already - the lithium preset handles the absorption/float behaviour properly and they cope well with the slightly dodgy shore power you get on some canals.

Also, what's your BMS? Some cheaper units get unhappy with the temperature swings you get moored up in winter. That might be relevant to the snags you've hit.