Golf cart lithium battery and solar

Been down this rabbit hole myself when I was kitting out the motorhome a few years back. Golf cart batteries are tempting because the price looks right, but you're essentially gambling on whatever cells they've stuffed inside that week.

The real question nobody asks upfront is what BMS are they running? Some of the cheaper golf cart lithium packs come with a BMS that throws a wobbly the moment you try to charge them from solar with any decent MPPT controller. Had a mate who paired one with a Victron SmartSolar and spent three months wondering why it kept going into protection mode.

For my cabin setup I ended up going with Fogstar cells and building my own pack — more faff but at least I knew exactly what I had. Cost wasn't actually that much more once you factor in the peace of mind.

If you're dead set on a golf cart lithium, things I'd want to know:

• Who made the cells? EVE, CATL, or a mystery brand?
• Does the BMS communicate with your solar controller?
• What's the actual C-rate for continuous discharge?

Solar pairing is usually fine as long as your MPPT is set up properly — lithium charge profile, correct absorption voltage. Renogy kit works well enough if you're on a budget, Victron if you want it to just work and not think about it again.

What controller are you planning to run with it? That'll change the advice considerably.

@MountainHermit the "price looks right" bit is doing a lot of heavy lifting there. I went down a similar path when I was fitting out my shepherd's hut and nearly pulled the trigger on some suspiciously cheap cells from a well-known auction site.

The problem with golf cart lithium repurposes specifically is you've got no idea what duty cycle those cells have already seen. Could be 200 cycles deep before they reach you.

Ended up just biting the bullet on proper Fogstar cells with a decent JK BMS. Cost more upfront but at least I know the chemistry, the capacity is genuine, and the BMS will actually protect my Victron setup properly.

The "savings" on dodgy golf cart pulls tend to evaporate pretty fast once you factor in the matching headache.

@MountainHermit nailed the core issue but there's another layer worth flagging — golf cart packs are typically configured for 36V or 48V traction applications, so if you're trying to squeeze them into a 12V or 24V solar system, you're either splitting packs (voiding whatever warranty exists) or adding complexity with a DC-DC stage.

I went through something similar sourcing cells for my van build before eventually going Fogstar Drift. The lithium golf cart route meant I'd have needed a custom BMS anyway, at which point you're basically building from scratch.

If budget is genuinely tight, a second-hand EV module — Nissan Leaf cells particularly — with a proper Daly or JK BMS will get you somewhere far more predictable. Victron kit plays nicely with both once the BMS communication is sorted.

What actually determines whether a golf cart pack will play nicely with a standard solar charge controller? Is it purely the cell chemistry or does the BMS configuration matter more?

Asking because I've got a Victron SmartSolar on the static caravan and I'm trying to work out whether the absorption/float voltages can even be set correctly for whatever cells end up inside one of these packs — or whether you're essentially flying blind without proper cell specs from the manufacturer.

Has anyone actually got documentation out of a golf cart battery supplier that was worth reading, or is it all vague marketing nonsense about "lithium technology"?

@SmartSolarNerd it's rarely one thing — it's a stack of conditions that all need to align.

The critical factors I'd look at:

• Nominal voltage match — your controller needs to see the pack as the chemistry it expects
• BMS communication — does it speak to your controller, or is it a dumb BMS just doing basic protection?
• Charge profile compatibility — golf cart packs often want a specific absorption voltage that doesn't map cleanly onto standard LiFePO4 profiles in something like a Victron SmartSolar

That last one caught me out early on. My SmartSolar was technically "working" but cycling the cells in a range the BMS hated. Took a fair bit of digging through VE.Smart data logs before I spotted the pattern.

Purpose-built leisure cells from Fogstar or similar just remove that guesswork entirely.