I never thought of "fixing " a car battery with wine. However you can buy battery acid to top off your battery with. It is very hard to find. And I may have, once a long time ago in a place far far away, topped off a battery in my 1973 Dodge van with vinegar. Don't tell any body. I sold it that day.
Yes adding a small amount of pure.(or diluted) acid to your cars battery will give it a boost. BUT.
It will also kill it.
Those batteries are designed for a certain concentration of a certain type of acid. This keeps the electrons flowing at a prescribed rate. When the battery is already almost dead, and you need a boost, adding more acid to the mix will push it beyond its limits. You can start your car. Yes. Now go to the auto parts store and buy a new battery. Your car will not start tomorrow.
As far as cutting up other batteries for new smaller ones. Buy A/C adapters and be done with all those little batteries anyway.
I buy small batteries at Christmas for the Krap my Grandson gets and then I tell his mom to go get the adapters for those toys. (I keep all the old adapters from stuff that has died over the years so I probly have one in the box in the garage.)
S.