battery question

[artv]

Hi everyone .....I was reading about wet cell batteries ....it says that at the plus terminal , there is an excess of positive ions,at the negative terminal there is an excess of electrons , when connected to a circut the electrons flow from - to load through load back to + because the electrons want to get to those + ions at the + terminal.What prevents the electrons from just going directly to the + terminal within the battery itself??......thanks for any input...........artv

[wooferhound]

The plastic battery shell is an insulator and electrons will not flow in it, just in conductors.

[zap]

What prevents the electrons from just going directly to the + terminal within the battery itself??

The electrolyte.


edit
Somewhere in this mess of a computer (or on another one) I have a pdf that explains it well and has diagrams but this one should explain it well enough:http://www.productivitydevelopment.com/22%20Battery.pdf

[artv]

Hi thanks for the replies ..........when the battery is dead I think I read it is because you get a build up of something on the plates inside this prevents the chemical reaction from taking place .....could you remove electrolyte fill battery with clr to dissolve coating on plates then refill with new sulfuric acid ........then have a new battery....artv

[zap]

There are many reasons a battery could be dead.

The "...something on the plates..." that you mention is sulphation (also spelled sulfation , the term is used interchangeably).

I assume when you say "clr" that you mean the cleaner CLR which is an acronym for Calcium, Lime, Rust.
I've never tried it.
DISCLAIMER
Batteries are dangerous
If you don't have training in dealing with batteries then take the battery you're talking about to a recycler or scrap dealer and get a new battery.

With that said, I'm not a chemist and I've never taken a chemistry class but I doubt CLR would do anything towards desulphating a sulphated battery because the sulphation on the battery plates isn't calcium, lime, or rust.

If you have a battery you want to try it on, go for it.  But take precations and assume the battery will blow up with just a drop of CLR.
Before you do that you might want to do a google search on sulphated battery.
Sometimes you can bring a sulphated battery around by doing a few deep discharge/charge cycles.

Good luck and be careful.

[artv]

Thanks Zap ......your assumption of Clr is correct I'll fill it from a distance outback see what happens if it works I'll let you know.............artv

[frackers]

Hi thanks for the replies ..........when the battery is dead I think I read it is because you get a build up of something on the plates inside this prevents the chemical reaction from taking place .....could you remove electrolyte fill battery with clr to dissolve coating on plates then refill with new sulfuric acid ........then have a new battery....artv

Pretty much no chance. A fully charged wet lead cell has one electrode as metallic lead, the other as lead oxide. They sit in sulphuric acid. A discharged battery has lead sulphate on both plates. This process is mostly reversible but the plates are not solid - they are a matrix that is designed to increase the surface area to maximise the amount of active material. If you want to 'clean out' a battery then you need to chemically remove the lead sulphate from the matrix by which time you'll probably find the whole plate falls apart.

Most dead batteries in my experience are so because the plates are lying on the bottom of the casing where they have disintegrated.

Might be worth noting that batteries are often supplied 'dry charged' This means that one plate is metallic lead as you'd expect, the other has been made of lead oxide (it looks like a fire brick!!) and the acid is added just before fitting.

[artv]

Thanks Frackers ........what about  a battery that froze ,was only six months old but forgotten by the time I remembered it wouldn't take a charge .......very cold winters here.....artv

[frackers]

If the battery froze then it was shot beforehand. I can't remember the freezing point of sulphuric acid with a specific gravity of 1.25 (i.e. fully charged) but is something like -50c - I doubt your winters are that cold!!

[artv]

well -30  -35 plus stored in unheated out of sunlight shed ,was brand new..............no way to bring it back?......artv

[bob g]

if the battery was in poor state of charge an subjected to temps low enough to freeze it, then the odds
are it is junk.

can't hurt to put it through a good charge to find out, and do an equalization on the batteries, but
if i had to bet.... the results are not going to be good.

bob g