If your battery is not already damaged irreparable (reading much less than 10 volts on the voltmeter), Epsom salt will restore it. However, it's vital to take all the needed precautions to avoid crashes. Baking soda will counteract the battery acid in either case, enabling you to dispose of it https://simonpsrpm.ageeksblog.com/33864453/the-war-against-lead-acid-battery-repair-epsom-salt