Resurrecting this thread to find out about the batteries. I get all nervous thinking about starting a fire if the compounds mix and cause a "short" condition... how much "black stuff" is needed? A pinch? A spoonful? A D-cell battery complete?
The "original" home brew recipe I posted on my site indicates a bit more than that for Zinc phosphate (a "shot glass full" which is about 4 fl oz), but I'm not sure about the Manganese phosphate amount.