If you have a shorted cell, scrubby plates, rust, or other inner physical "damage", this won't help. http://rd.adingo.jp/?p=9uC4QfbzB9Do4Zja8N4oQU-A6aftAVBj3MPo9BA6oK_C2fv68Wqk8W-j1Fp2XlAxEx5ZFibFF7F-3Z5MFkLz-6Lpru0SsAEEtIfxnFDWkyxQ56EbzBksCQYE9gD1jtXdW3i-Ol1WVl5IRjnlkT4w2lvRJYIMRxGEq2xjnF2lZTBSBIH7aqT9WemKD1gWrO6DyOpm-jxw2dTAcN3ytAyDmsdmESWhMWO8kbpe0K41eajRG3li7kVWEQDz_oRFnNEguBRAk3NIMPWGeI8bz9HLHOkOX8-hI2f4I_1tJ0Dz0-lSlXaw__XlayCSHK56v-Zxg57y4xY8M51-JMxElSuuq1TS7xliWIwl8MDbOyp9Hf8.&v=VKVV1Ts6nlY.&k=1&guid=ON&u=https%3A%2F%2Forganicsphere.ca%2Fquestion%2Fepsom-salt-car-battery-at-a-glance%2F