12V 300Ah LiFePO4 Battery $244 Eco-worthy 12v 100ah battery $106

Those are interesting price points, especially the Eco-Worthy 100Ah at $106 — that's getting into genuinely tempting territory even converting to sterling.

That said, I'd want to know a few things before pulling the trigger on either of these:

BMS quality — the headline specs on budget cells are often fine, but the BMS is where corners get cut. What's the continuous discharge rating and does it have proper low-temp cutoff? In a van that's sat outside in a UK winter, that matters a lot.

Cycle life claims — most of these budget units advertise 2000+ cycles but that figure is typically at 80% DoD and 25°C ambient. Real-world in a van conversion will be quite different.

Cell grade — are these A-grade cells or are we talking B-grade rejects from the big manufacturers? The price point on the 300Ah suggests the latter is possible.

I've got a pair of Fogstar Drift 100Ah units in my Transit build and whilst they weren't cheap, the confidence in the BMS and cell consistency has been worth it. No BMS trips, no weird voltage sag under heavy inverter loads.

Not saying the Eco-Worthy is rubbish — plenty of people run them fine — but I'd want to see a teardown or at least some long-term discharge test data before recommending them here.

Anyone on here actually running either of these? Particularly interested in how they behave on a Victron MPPT with absorption charging enabled. Some of these cheaper batteries throw a wobbly when the charger pushes 14.6V.

Kate1970 | 847 posts | ⚡ Solar Addict

@Tommo Those prices do look attractive on the surface, but I'd be cautious about the cycle life claims from lesser-known brands. The real cost isn't the purchase price — it's cost-per-cycle over the battery's lifetime.

A decent quality LiFePO4 should deliver 2,000-3,000+ cycles. If a cheap one only manages 500-800 before capacity degrades significantly, you've actually spent more in the long run.

Also worth checking:

• Whether the BMS is genuinely adequate for your load
• Cell grading (A-grade vs B-grade cells make a huge difference)
• What the actual warranty terms look like once you factor in returning goods internationally

Has anyone here actually run Eco-Worthy batteries long-term? I've seen mixed reports elsewhere. Would love to hear from someone with 18 months+ of real-world data rather than just initial impressions. 🔋

CamperClive | 234 posts | 🔆 Solar Curious

@Tommo What's the cycle life claim on that Eco-Worthy? I've been running a Fogstar Drift 100Ah in my shepherd's hut and the warranty and cycle count transparency was a big factor for me — 3000+ cycles clearly stated.

With budget cells, do we actually know if it's genuine Grade A LiFePO4 or are we getting Grade B rejects? Has anyone pulled one apart or tested capacity with a proper load tester rather than just trusting the label?

Also curious whether these ship from UK/EU warehouses — import duties and potential customs hassles could close that price gap pretty quickly after Brexit. What's the BMS spec like on the 300Ah? That's the bit I'd really want to scrutinise before connecting anything to my boat's system.

OldSailor | 2,341 posts | ⚙️ Off-Grid Obsessive

Dollar pricing on a UK forum is your first red flag — the landed cost with import duty, VAT, and inevitable courier surcharge will cheerfully devour that bargain faster than a Victron SmartShack devours your wallet.

@Tommo The real number to interrogate isn't the headline price but the cost-per-cycle — take purchase price, divide by the warranted cycle count at your DoD, then compare against a Fogstar Drift 100Ah which I've been running two years without drama.

Eco-Worthy's BMS protection specs are also worth scrutinising; some budget cells ship with BMS boards rated generously at "optimistic" rather than actual amperage, which your Victron MPPT will find out about at the worst possible moment.

BordersOffGrid | 512 posts | 🔋 Battery Botherer

@Tommo Dollar pricing is doing a lot of heavy lifting there 😄 By the time you've added shipping, import duty, VAT, and the inevitable "customs adventure" fee, that £84 bargain has quietly become £140 and a nervous two-

BoatOllie | 891 posts | ⚓ Liveaboard

Worth adding that on a boat the stakes are a bit higher than a campervan — you can't just pull over if something goes wrong with your battery bank. I've nothing against budget LiFePO4 in principle, but I'd want to see proper documentation for the BMS: what's the cell-level protection doing, and what happens under fault conditions? Eco-Worthy have improved over the years but their support if something goes wrong tends to be... sporadic. @OldSailor will likely know better than most what marine use actually demands of a battery. Also worth checking whether these come with a Bluetooth monitor — at that price point I'd be surprised if they do, and knowing your state of charge properly matters enormously with LiFePO4.