The last person that touched it screwed it up. In your case it was the people that charged your battery the first time it was dead.

As stated above, you corrected the problem by your actions.

Thanks guys. Thanks everybody.

Even all those screwing operations have happened, the subject battery have gone five years. Three total years with correct polarity and two years with reverse polarity.

It was a Warta. I am sure this battery is owing his long life to my seldom usage for the car. A few engine start in the complete week.

Eventually, the car have been sold with the same battery fitted on. Battery was still operational.

Did you tell the idiots who charged it backwards what they'd done? +ve and -ve are clearly marked on a battery. If they were anything like reasonable they would have paid for your alternator repairs.

Cheers...........Codey

I did. They did not believe a battery could be reversed.

I asked them to check the battery.

They checked. They satisfied. However they paid nothing.

They told that they do not have any official responsibility for each battery, of which coming them for recharging.

Crooks. I trust you won't be dealing with them again.

Interesting. I recently was checking a dozen or so used AA batteries that over a period of months came from various electronic devices (remotes, kid's toys, etc.). I suspected some might still be usable. Most were dead, a few were still good enough to use, but 3 had a negative voltage on it. And yes, I was connecting the leads of the DVM to the correct terminals of the batteries. They are not rechargeable type batteries either. My theory is that they were installed in one of the devices backwards opposing a larger number of batteries. I can't really imagine why the devices would have been working if configured that way, but I can't think of any other way for the batteries to reverse polarity. Is it possible they they were that way from the from the manufacturer?

Your small, non-rechargeable batts probably got charged in reverse by leaving the torch or radio on when the batts went flat. the batts are never exactly the same therefore when the first one reaches zero the remainder still have some charge and now they will pass charge current in the wrong direction.

Chas

Chas,

Thank you. I hadn't thought of that.

It would make a fascinating experiment to see if periodically reversing the charge on a lead-acid battery would extend the service life. Could be a great cost saver for golf cart and home windmill installations.

Exactly it's funny but correct, experimentally proved.

I am sure this rule is written nowhere.

Reversing polarity would be an interesting experiment since discharging a lead acid battery usually destroys it.

Of course trying to reverse the polarity of a semi or fully charged battery results catastroph. Trying to recharge in reverse way draws more current than the short circuit. (Twice of the short circuited amps, however the current is limited somehow on the conductor loop) First the rectifying diodes for the charger blows off.

The battery was totally flattened with zero voltage during they reversed.

Kindest Regards

i was thinking/wondering that exact thing when i saw the service life he got out of his battery.

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