Battery Question

[ee904age]

I've googled this and had a lot of conflicting info. Last summer our boat battery went flat, I tried charging it with my normal micro processor type charger for a few day but no go. We bought a new battery and carried on. Over winter We've had a dual battery setup put in the boat and would like to try revive the old battery to use as the "house" battery to run stereo, fish finder, vhf etc.

I've put my multimeter on the old battery and it's reading 9.3v, my charger wont even switch on when attached to it. Is it toast? Or is there some way to revive it enough to use on a low draw setup?

The new setup on the boat is 4 way, with Main, House, Emergency Parallel, and a VSR (which is for alternator charge I think?) So if the battery does fail we can still use the emergency parallel to run everything off the good battery, so no big deal if I cant get it back to 100%, but anything would be better than forking out another $200-300 that would be better spent on gas and bait than another new battery!

[Grrrrrrr!]

If the old battery was left flat for more than a few weeks, its probably history.

You could try connecting up the old battery to the charger and using a good battery to give it a bit of a jump while its connected to the charger.. should raise the voltage enough to kick the charger into life. Of just chuck it in your car, crash start it and go for a good drive.. just dont stall it

[Stu-]

Those micro processor controlled chargers can be a right pain in the ass some times. Ive had several boat batteries with the same scenario - gone flat, wont charge on flash charger. However... I'd got an older basic plug and go style charger and I just leave them on for 48 hours or more (have left for a week in the past) and they've all come right again. One hadn't been used in several years, left it on charger for 3-4 days and its still in use several years later.

Another good idea is to invest in those cheap solar chargers from Supercheap/Jaycar etc. They have inbuilt controllers and will shut down when the batter hits 14v but trickle charge when the voltage drops.

[stolic]

is the battery a "sealed" maintainence free type? or does it have the plugs for topping up the fluid? If it is serviceable, repco/supercheap etc sell INOX for about $10... has worked a charm on the old mans boat batteries that appeared to have died over the winter ( and 4 yrs later still going strong without being touched)

[Flannelman]

The lead plates have sulphated. Once this happens its scrap as its irriversible

[stolic]

The lead plates have sulphated. Once this happens its scrap as its irriversible

not according to this...

Approximately 75% of lead-acid battery failures are caused by a build up of sulphation on plates and separators. One treatment with INOX Battery Conditioner dissolves and helps prevent the recurrence of this battery killing sulphation, restores the active ingredients and allows the battery to operate at full capacity.

INOX Battery Conditioner will not harm batteries, it is purely an agent to help keep the electro-chemical process active longer in lead-acid batteries.

INOX Battery Conditioner can be added to a battery at any age, the older a battery is, the less effective INOX Battery Conditioner may be. If an older battery will not hold its charge properly, has recharging problems or is just generally slow, the addition of INOX Battery Conditioner in 95% of cases will give the battery additional new life for up to
2 - 3 years.



But then that is from the Inox website so digest with sodium iodide

http://www.inox-mx3.com/product_detail. ... PLICATIONS

[ee904age]

Gave it a kick start with a 15 amp transformer type charger for a couple of hours to get the voltage up as I think thats why my other chargers wouldn't touch it. Put it back on the "smart" charger and now its accepting a charge, up to 75% now since last night.

If it holds the charge is another question.

[xsspeed]

Interested to hear result. i just replaced my boat battery after the old one died after 6+ years. Still have the old one but it wouldnt hold charge

[Lloyd]

As above, the smart chargers aren't completely smart. Dead flat or bike batteries they wont even try to charge. The big old meaty chargers that just put out up to 20A quite happily are the ones that will kick a bit of charge back into them. After they've been on for a little bit then the smart chargers are happy enough to keep things going.

The solar chargers aren't a bad idea either. I've got one that was reasonably cheap and supposed to put out 100mA. Even in fairly low sunlight it'll light up with a large portion of the panel covered.

[ee904age]

After leaving it on the charger for about 48 hours at 4 amps, it seems to have done the trick. I put it back in the boat, switched in nav lights and stereo and left it for about 6 hours. Came back and it was still running. Didn't want to leave it any longer as it isn't a proper "deep cycle" battery, and realistically that's our average days fishing. Took around 3 hours at 4 amps to bring it back to full charge.

I think its a success, although I wouldn't rely on it as a main starting battery.