Today I learned about....batteries

Whats up with the nuke batteries? Divulging secrets here is like bragging to your friend about the hussy you banged last night. I remember a member here who would not tell us where the 2nd VIN was stamped on a 68 Dart. I was talking to an old Korean era Submariner who sailed on the "Redfish" We spoke about 40 minutes while I worked on his phone line. That sub was sold to Disney and they made a few movies on it. Old WWII Fairbanks Morse 10 cylinder Diesels. When the ship did an emergency dive onto batteries (old lead acids!) the engine room heated to 140F with no cooling pumps for the diesels that just shut down. They made distilled water for the batteries and whatever was left over they used for the crew, ie bathing, cleaning, drinking...I told him that was some serious duty in those iron coffins, he said it was the best duty in the Navy.