Richie

WWEST, my technical English is not that good but I will try to explain what I whitness at the shop with battery's.

When we get a customer that has a battery that has been discharged because for example the car has been undriven for a couple of weeks so the normal drainage has drained the battery completely and they have started the car with the jump cables and the car still will not start after a long drive (which should have charged the car through the alternator) we will try to charge it on an external charger.
The charger we use can charge high and low.
You can charge that battery all day on the high level and the battery will not accept anything but I have seen when we charged them on the low setting the battery will start to charge after a couple of hours.

Do not ask me why this works, I don't know the details, I have just seen it work.

I know it my explenation is not that great but I hope you get the picture.

wwest

But I have never experienced the circumstance you quote, not saying it doesn't happen, at all.

But I wonder...

Many, many times I have seen circumstances wherein the car's system could not fully charge the battery because the battery's terminals simply needed cleaning. The other instance I have seen is that the battery is actually fully charged but still will not put out enough juice to start the car due to poor battery terminal connections.

Once long ago I was standing in a repair shop when a lady came in with a car that had this problem. When I walked over and looked, as the mechanic was telling her that she likely needed a new alternator, it was obviosu to me that the terminals were so dirty and corroded she couldn't passibly have a good electrical connection. The mechanic got not just a little bit upset when I told her that likely all she really needed was the terminals cleaned, polished, and retightened.

A maintenance procedure I go through every spring, cleaning, polishing and being sure my battery terminal are on tight.

Is it at all possible that in the process of removing the battery to charge it what is really happening is you're inadvertantly providing a good electrical connection rather than charging the battery at all?

Richie

That of course is the first thing you should check when having starting problems.
Most french cars and a few cheap japanese cars already have bad clamps that do not really fit the battery terminal well.
The instances I told you about did not have any problems with terminals or clamps.
I also check the clients alternator, because if the alternator is shot (loading to high and damaging the battery or loading to low and not charging the battery), most german cars with their bosch alternators have the problem of not charging high ebough or overcharging.
If this is all OK, then we put them on the external charger in the manner I described before.


I do not think that that will be the problem, as you can see from the text above, we already check that part.

LS4fun

There is no "color" to electrons. I believe the method in which a battery works is that a fully charged battery has all electrons on one side of it (anode or cathode) and none of them on the other side (cathode or anode). As a device is plugged to the terminals, the electrons flow (current) from the + side of the battery to the -and in terms powers the device. When the electrons have all moved to the - side of the battery, there is no more flow or current and the battery is dead. To reverse this process and make battery usable again the electrons have to be placed back to the + side of the battery (anode or cathode in electrolytic solution). You are actually moving electrons from one solution on one side of battery to the other.

willard west

is right again.

That "colored electrons" part was a joke....

What I was trying to say was that it takes electron flow (of ANY color or nationality) to charge a battery, and those lead plates don't have any way of knowing the source of the inflow of electrons.

They have no method of being choosy.