Bongo Fury

Hello

We have had a 110ah leisure battery on our Bongo for 3 years. It has always been looked after, i.e. trickle charger on regularly, esp. in winter, and has always worked perfectly until it went from being 100% good (i.e. 2 days parked up, fridge running, no probs) to not working at all well (30 minutes parked up, fridge running) last week during our holiday.

I have given it a good charge and it initially reads more than 12V across the terminals when you take it off charge but quickly drops to 10.7V ish when you put a load on it.....Water levels are fine in the battery and it gasses healthily when charging.

One possible relevant factor was that we bought it as a Bosch leisure battery but I have since been told that Bosch don't make leisure batteries and it is hence simply a conventional large car battery intended for starting vehicles only.....Just to muddy the waters though, a friend of mine said that he was of the firm opinion that all the 'deep cycle' leisure battery stuff was bull**** anyway and a car battery would work just as well.....

If any experts can tell me, does the battery reading 10.7V after a long charge mean it is definitely fit for the wheelie bin only? I would have expected a leisure battery to last a long while (5,10 years, maybe more) if looked after. Is this unrealistic? 3 years seems a bit rubbish....

Hope you can help, Dave

A voltage of only 10.7v indicates a very flat battery, or possibly one with a dead cell.
If you have a decent charger then put it on charge for at least 48 hours, then let it rest for about 6 hours and measure the voltage again (what are you measuring the voltage with ?) if at that point the voltage is less than 12.6v then you have a dead battery.

If it is dead, it should have a scrap value, don't just sling it out may only be a fiver or so, may be a bit more, but rising scrap prices means the lead in it is worth sumat - so not a total loss

Geoff,

Thanks for reply. Measuring voltage with a multi meter across the terminals.

Think it is probably kaput in real terms (i.e. fridge only worked when engine was on when on holiday last week....). Guess I was just fooling myself really that it might be ok if I charged it for ages. Always been a tight-wad!

Kirstie,

I must admit I hadn't considered that, thanks. I can offset it against the cost of the replacement!

Cheers guys

Ok well if it is a reasonable multimeter and not an old moving iron gauge then provided you have measured at the battery terminals then its not sounding to good, still worth a check after giving a good charge however. I was having doubts about my own L/B during Feb. but simply turned out to be a little corrosion on fuse blades when I had them all apart for a check, hence giving poor charging and suspicion that the battery was beginning to show its age (3 years +).

The battery does sound pretty dead but I agree give it a good 2 plus days on charge, then leave for 12 hours and check the voltage.

Leisure battery construction is different to car starter batteries. Your LB needs to give you a lot of power at relatively low rates for a long time, where as the starter battery needs to give you a lot of power over a very short time. They are made differently inside, so worth buying the right type for the application.