I take 4 junk 12V batteries and bring them back to life with a combo of epsom salt and used battery acid.
I've now done a part 2 with a cold cranking amp test and opened a battery up so you can see the process. Link below,
https://www.youtube.com/watch?v=RNnSYuTuLk4&t=46s
#battery #batteryreconditioning #oldbattery #epsomsalt