When a 12volt battery stops taking a charge, I believe that it's possible to desulphate the plates .?

simple go into chemists and get some Glaubers Salts, it looks like washing soda.

Dry it over radiator as it will have too much water content and once a dry white powder put a tea spoon full into each cell.

It is actually hydrated Sodium Sulphate .....take the water out and it become Sodium Sulphate!

Due to Sodium being what it is, it has an ability to take on extra atoms.

These atoms will be Lead Sulphate (that is what the Lead plates in your battery will be coated with)

Once removed the battery will then take on and give up charge more readily!

The now "full" atoms of Sodium Sulphate will sink to the bottom of the battery where they will do no harm.

You can get more "life" out of a battery that is showing its age.

YEP

Take it to Battery Doctor or Battery Medic and exchange for one rebuilt by this process.

Half the price of new and with warranty

Not worth the process as if it were that easy everyone would be doing it. Sulphate is no the only reason anyway

If it were an economic proposition it would be on offer commercially. I don't think it is, so I don't believe it is worth trying.

yes, you just buy a new battery, I have had a couple reconditioned batteries and they don't last long.

Some battery chargers will do this.

put it the bin and buy a new one yer tight git

new battery with CdSO2(?)