Anyone else struggling to keep a 12v compressor fridge running overnight on a single 100Ah LiFePO4 battery?

I've got a BougeRV 30L compressor fridge drawing around 3-4A average and a single 100Ah LiFePO4 (Fogstar Drift) in my Transit conversion. On paper that should be plenty — 100Ah usable down to 80% DoD gives me 80Ah, and the fridge should only need maybe 50-60Ah over 12 hours. But in practice I'm waking up to a battery that's sat around 20-25% by morning, especially on warm nights.

I've checked with a Victron BMV-712 so the readings are fairly trustworthy. The fridge is set to 4°C and the van does get warm overnight in summer — ambient inside probably 22-25°C — so the compressor is cycling more than I'd expect. I'm also running a small Maxxair fan on low which pulls maybe 0.5A continuously, so that's another 6Ah gone overnight. Still, the numbers don't quite add up to me.

Has anyone else found their real-world overnight draw much higher than the theoretical figures? I'm wondering whether it's worth adding a second 100Ah battery or if there's something obvious I'm missing — insulation around the fridge, lid vs front-opening efficiency, that sort of thing. Would love to hear what setups are actually working for people.

@LOQ_Camper what's your ambient temp like overnight? I ask because my compressor fridge (similar size) absolutely hammers the battery when it's warm — duty cycle shoots right up and those "3-4A average" figures can be optimistic in summer.

Also, are you accounting for any parasitic draws alongside the fridge? Even a small inverter on standby or a split charge relay can nibble away more than you'd expect.

Have you actually logged what the Fogstar is sitting at by morning? Curious whether it's genuinely running flat or whether the BMS is cutting out early for another reason — voltage sag under load can sometimes trigger a premature low-voltage disconnect that looks like a flat battery but isn't really.

@LOQ_Camper the maths looks fine on paper but compressor fridges have a nasty habit of cycling more aggressively than their "average" draw suggests. Peak inrush on startup can be 8-10A for a brief moment — not a drama in itself, but if your BMS has tight overcurrent settings it might be throttling things oddly.

Also worth checking: what's your actual resting voltage after a full charge? Some of the cheaper 100Ah cells aren't quite the full ticket capacity-wise.

I run a slightly larger setup in my static van (two Fogstar Drift 100Ah in parallel) and even then, a warm summer night with the fridge working hard will chew through more than you'd expect. One battery cutting it very fine I'd say.

What's your BMS rated at?