car battery condition advice

[xpress]

i just checked a few car batteries i had lying around because i think one of mine needs replacing.

i have these three:

11.89 (type 048 pavilion)
11.27 (type 063 pavilion)
11.32 (varta)

they were left standing in a garage, and haven't been charged when i took the readings, the type 048 is first in the lineup to be slow charged.

what do you think about the condition so far? worth keeping around?

[bmcecosse]

No way to tell if they have been lying around - charge them up and then try them. A solar charger is worth it's weight in gold......

[Mogwai]

Open Circuit--------Approximate-------Average Cell
Battery Voltage----State-of-charge---Specific Gravity
------12.65+----------------100%--------------1.265+
------12.45------------------75%---------------1.225
------12.24------------------50%---------------1.190
------12.06------------------25%---------------1.155
------11.89--------------------0%--------------1.120

If any of the cells gas excessively when charging or under a high discharge (engine cranking) they are likely to be scrap. would be worth using hydrometer to test the individual cells once charged
leave to settle for a while after charging before testing though

[xpress]

Thanks. If any of the batteries are under 11.89 before charging are they likely to be scrap?

[bmcecosse]

Not necessarily - charge them!

[xpress]

Nice one. 12.93 on the 063 left an hour after charging. Will check it on load in a bit. Charged overnight.

How long to leave them on charge. Is it ok to permanently connect them on a slow charger. I have an up to 1200cc slow and fast charger.

[xpress]

Going for it today.

Tried a 12v vaccuum cleaner the smaller pavilion didn't like it. The others seem fine with it.

Bmc I attached the solar panel for first time is it likely to charge a battery as quick as a car battery slow charger?

[bmcecosse]

No - it's a long slow trickle charge - basically just keep s a battery nicely topped up - provided it's facing south....... with a clear view of the sky.

[MarkyB]

A 12v vacuum cleaner isn't really a good test, unless the battery will start a car after it's been charged it's scrap.

Lead acid batteries hate being left flat, they won't last long at all.

Unless a battery has been taken out of a car because the car is going to be scrapped, the chances are it's been replaced because it's scrap itself but has a value as it's full of lead.

I'd suggest you weigh them in to the local non ferrous scrap merchant and put the money you get towards a new battery.

[nigelr2000]

The battery on my pickup was left for 3 years and didn't have enough life in it to even work the oil and ignition lights, gave it an overnight charge and it started the car fine and I am still using it a year and a half later so charge em up and put on a car with the coil disconnected and see if they spin it over for a reasonable time, no point in weighing in a perfectly serviceable battery just because it has been allowed to go flat. They don't always fail if they were in good nick before being allowed to discharge.