OK - I have one:
You can prolong (significantly) the life of your battery by adding a little bit of EDTA to it. In fact, you can even bring back a dead battery!
Bryant Stewart, former editor of Pickups n Panels in Print magazine, asked me for a sample of EDTA close to 10 years ago because he knew that I'm in the chemical business. I asked what it was for and he said that an old timer had told him to use it in his truck batteries. When I looked into it, I was surprised to learn that this is a known fact, but that the battery manufacturers do not add it to their batteries because it may almost put them out of business!
EDTA is a chelating ("Key-lay-ting")agent and will tie up metals.
You can order small samples for free from Dow Chemical and 4 oz sample is enough to treat about 10 automobile batteries. A little goes a long way.
This chemical compound has also found more recent use in circulatory therapy in humans.
Here's a couple of reference posts:
EDTA can bring back dead car batteries EDTA in Batteries Battery Revival with EDTA
