Short shelf life...maybe dried fruit would work too? Anybody tried sheets of
dried apricot or apple between copper and zinc foil? Rolled up like a jelly
roll?
/\/\/\/*=Martin

>
> ...I found that plastic soda
> bottle caps arranged in a honeycomb pattern (for density) filled with
lemon
> juice work the best. Each battery cell was filled roughly half with juice
> and I used common zinc galvanized nails and copper mesh for the electrodes
> (The copper mesh provided a greater surface area for the chemical reaction
> to occur and produced about three times the current output when compared
to
> a copper nail).
>
> Lemons work the best of all fruits (apples, oranges, lemon, limes, etc.)
> that I tried. Other foods I tried included [chilli] peppers and potatoes
> (potatoes are rechargeable!). The general rule of thumb is that a whole
> lemon will produce approximately 1 mA at 1 Vdc. I used the bottle caps to
> reduce the weight of the battery.

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