Surface water from gravity is the fuel of the cell

An acid-base battery is able to produce electrical current by manipulating the redox balance between water and molecular oxygen. It does this through the physical removal of hydrogen from the anode compartment, forcing oxygen from the dihydro to the dioxide state with the release of electrons. The biological cell is also powered from the combustion of hydroxide ions, and just like an acid-base battery it can also remove hydrogen by electrostatic substitution with cations like sodium and potassium, but it also has another tool in its toolbox for exploiting the electrons stored in water: the ionized surface phase of water, that is formed from pressure exerted by gravity