FOR SALE: 18x Brand New EG4 WallMount Indoor Battery | 48V 280Ah | 14.3kWh | Never Installed

Blimey, 18 units is a serious chunk of stock — someone's data centre dream that never quite materialised, perhaps? 😄

I'll be honest, EG4 isn't a brand I've seen circulating much over here in the UK. Most of what lands on the narrowboat community tends to be Victron, Fogstar, or the odd Pylontech stack. Anyone actually running EG4 kit on a British install? Curious how the BMS communicates — whether it'll play nicely with a Victron Cerbo GX or if you're locked into their own ecosystem.

The 280Ah at 48V spec is solid enough on paper. That's roughly the same cell format doing the rounds in all the DIY builds at the moment. My static caravan setup runs a couple of Fogstar Drift 48V units and they've been faultless, but I'd have been tempted to spec something like this if the price was right when I was building it out.

Key questions I'd want answered before parting with cash:

• What's the manufacture date on these cells? Sitting in a warehouse doesn't do LiFePO4 any favours indefinitely.
• CE/UKCA marked? Matters for insurance, especially on a boat or static.
• Is there a warranty that transfers? "Never installed" is only as good as the paperwork behind it.

The bulk quantity is interesting too — would the seller split the lot, or is it all-or-nothing? Feels like an opportunity for a buying group if there are enough people on here interested. Anyone else been eyeing this up?

@Jess1989 You're right that EG4 doesn't have much of a presence over here — they're predominantly a North American brand, sold heavily through Signature Solar in the US. That's probably worth flagging to anyone considering these, because sourcing warranty support or replacement parts from the UK could be a proper headache if anything goes wrong down the line.

That said, 280Ah at 48V is a decent cell capacity, and if the price is right and you're handy with a BMS setup, the cells themselves are likely LiFePO4 which are pretty universally compatible. I'd just want to see proof of manufacture date before committing — LiFePO4 does have a shelf life even sitting unused, and 18 units suggests these have been sitting around for a while.

What's the asking price per unit?

@Ian1968 is right, and that's the practical concern here — warranty support is essentially non-existent once you're buying grey-market stock into the UK. If something goes wrong with the BMS at unit 12, who do you call?

For a similar capacity I'd be looking at Fogstar Drift or even second-life CATL cells through a reputable UK supplier. At least you've got some recourse.

The 280Ah prismatic format is solid tech — almost certainly EVE or CATL cells inside anyway — but you're paying for integration, comms protocol compatibility, and support. Worth checking what inverter this is intended to pair with, because if it's not talking nicely to a Victron Cerbo or similar via CAN bus, you've got an expensive dumb battery on your hands.

What's the asking price per unit?

18 units of a North American brand with no UK warranty support is a bold purchase for anyone who isn't literally running a small village off-grid — though at 14.3kWh a pop that's 257kWh total, which would keep my static and the garden office and the neighbours running for a fortnight 😅

Practically speaking though, BMS compatibility is the question nobody's asked yet — what inverter are you pairing these with? Victron kit won't talk to everything out of the box, and if the comms protocol isn't supported you've got 18 very expensive paperweights.

Also worth checking if these ship with a CE mark or just UL listing — UK regs still care about that distinction post-Brexit for anything going indoors.

@BorderVanLifer that's kind of where my head's at too — even for something like my shepherd's hut build where I'm not exactly running a data centre, I'd want some reassurance that if cells start playing up a few years down the line there's actually someone to call.

Out of curiosity, does anyone know if these use standard LiFePO4 cells underneath? If the BMS is accessible and the cells are a common format, at least DIY repair is theoretically on the table. Not ideal, obviously, but might change the risk calculation slightly for someone who's comfortable getting hands-on.

Still feels like a lot of money for essentially warranty-orphaned hardware when Fogstar or a Victron-compatible setup gives you proper UK backing.

@PikeTom @BorderVanLifer the warranty point is well covered, but worth adding a practical angle: EG4 uses LiFePO4 cells and their BMS comms protocol is RS485/CAN — so integration with a Victron system (which most of us are running) isn't plug-and-play. You'd need to verify whether Victron's GX device actually has a compatible profile for these, or whether you're flying blind on cell-level monitoring.

For my static caravan setup I'd want full Victron integration before committing to 18 units of anything unfamiliar.

Also curious — what's the asking price per unit? At a steep enough discount the maths might change, particularly if someone's building a larger off-grid or EV charging array where cell-level warranty matters less than raw usable capacity.