Can you restore and rejuvenate an old dead car battery? I take an 8 year old dead battery that hadn’t been used in about 3 years and got it to take a charge. This was one of my “mad scientist” experiments to see if it was possible, and it is VERY possible with things you can get easily.
I tried many chemicals solutions to clean lead sulfate off the plates of the dead car battery. I tried using concentrated sulfuric acid, EDTA and citric acid, baking soda and water, as well as sodium hydroxide (lye). The baking soda did nothing (spoiler alert) the others did have a cleaning effect, but some were more destructive than others.

You can desulfate a battery using the method I did in this video.
You can get battery acid at the link below

https://www.acehardware.com/departmen...

everything else you should be able to get at walmart, lowes, or home depot.

Be sure to use protective gear when doing things like this. reactions can happen suddenly and without warning. Be safe. Most of all, wear a respirator. The gases created can be very toxic.

You can learn about lead sulfate here https://en.wikipedia.org/wiki/Lead(II...
The sulfuric acid I used I got at Lowes here https://www.lowes.com/pd/ZepSulfuric...

The lye I used I got also from lowes here https://www.lowes.com/pd/RoebicLabor...

Do not try to use magnesium sulfate (Epsom salts) to restore a battery. It does not work. I have no idea who came up with that, but it is bad science.