I was wondering, if you dump the acid how are you going to replace it?
Also the acid content changes with the charge. A fully charged battery will have high acidity.
A dead battery will have low acidity.
I once saw someone try to charge a dead battery and the poles were wrong and it exploded in his face. I also saw someone try to check the level in a battery with a lighter.
also exploding in his face.
Both of them came out OK. Now try that with a fully charged battery and you have a different story. Of course noone attempts charging a charged battery.
Anyway if you want to dump the electrolyte totally discharge the battery first. Then when you need it just add water.
Danny