New battery, grow your own.

Great idea. When the battery finally gives out, I'd walk into the store and say "my battery died" and really MEAN it

 

But just think of the "potential" hazards:

After these viruses get genetically mutated by a mad scientist (so that they become infectious to humans), one person gets infected with the cathode virus, and another gets infected with the anode virus.

They walk past each other in a public place, unaware of the "potential" danger. The opposite polarities attract, they come crashing together, overheat in a few milliseconds from the massive instantaneous current flow, and then spontaneously burst into flames and explode.

Not a pretty sight.

 

(Sinister maniacal laughter, followed by evil scheming ...)

Why, if I get any more excited I just might faint