665
Battery breakthrough as 99.99% of lithium extracted from old cells
(www.independent.co.uk)
This is a most excellent place for technology news and articles.
I prefer 9-Volt. It's shockingly good.
Do you have lithium 9 volt blocks or do you only get your zinc and manganese from it?
But it's probably important to take care of all your nutritional needs and different 9 volt batteries could provide you with quite some of that.
Clever thinking!