Messing with batteries can be dangerous do so at your own risk and wear protection.
Part 1 converting the battery from acid to alum
Part 2 testing the battery again more extensively almost 6 months later www.youtube.com/watch
Started a drain over time test you can view the first 16 days results here www.youtube.com/watch
Final testing 3 months drain with no charge started truck 4 times including the last starting the truck in 10 degree F
1 cup or 8 oz of alum "aluminum sulfate" in a 1 gallon jug then fill the jug with water "it is best to use distilled water"
Same for the baking soda 1 cup per gallon. The baking soda mix is used after draining the acid to neutralize any left over acid. You can then after rinsing with that rinse with plain water to get out the baking soda mix. Then you will put in the alum mix filling to just above the plates and then charge.
My first attempt at taking a bad 12 volt battery in this case a deep cycle boat battery and replacing the acid with alum water " food grade aluminum sulfate" so that it will take a charge, worked so well I was able to start my truck with it after just charging it overnight with the alum water in it. Before replacing the acid in the battery it would not even hold 3 volts.
I used this food grade aluminum sulfate www.amazon.com/gp/product/B00016Q6BK
there are many other companies that sell it check your local grocers or feed mills as long as its food grade aluminum sulfate it should work fine.