Oh bugger! 7.2Volts leisure batteries

[Jev88]

Well that was an expensive mistake. Before hospitalisation 5 weeks ago I moved the RV into winter storage. Accidentally left inverter on and that meant a small speaker and the TV on standby (and the inverter itself) sucked the life out of my leisure bank.......

Just as well I have a Fogstar in the garage waiting to be fitted.

 

[Rapido925M]

In spring I discovered that the solar panel keeping my lawnmower battery topped up was covered with leaves (yes, I know, I should have checked). The battery was at 5.6V
Connected my CTEK charger and up it went to 13.4V: been fine ever since

Don’t assume the worst.

 

[poppycamper]

Funsters on here keep insisting that once a battery is flattened it is toast and needs binning.... not necessarily so..
When I first got current moho, 7 yrs ago I stupidly let the starter battery go flat after a week on a THS..
Jump started van, and 7 yrs down the line the battery still working effortlessly...
I can still leave van sitting for 2 or 3 weeks and engine will start first time,,, even in winter..

 

[AdrianChen]

Funsters on here keep insisting that once a battery is flattened it is toast and needs binning.... not necessarily so..
When I first got current moho, 7 yrs ago I stupidly let the starter battery go flat after a week on a THS..
Jump started van, and 7 yrs down the line the battery still working effortlessly...
I can still leave van sitting for 2 or 3 weeks and engine will start first time,,, even in winter..

I think a lot depends on what actually happens, and the quality of the battery. It's a matter of chemistry that the battery will sulphate if left at low voltages so if properly flat for a few weeks, that process will be irreversible and terminal - if only for a brief period, less sulphation will have occurred so the battery may only loose a small amount of its capacity.

There are "mechanical" issues as well, since cheaper batteries may suffer from plates warping if discharged deeply and too fast. especially if they have also suffered from being in an environment where they are subject to knocks/vibration, when the lead antimony can dislodge from the grid.

That to me is why its good to get a decent brand from a reputable source.

But with a Lithium in the wings the OP is well prepared!