  Electronic logic gates are the basic building blocks of every computing and
micro controlling system. Logic gates are made of switches, such as diodes and
transistors. Ion-selective, ionic switches may emulate electronic switches
[1-8]. If we ever want to create artificial bio-chemical circuitry, then we
need to move a step further towards ion-logic circuitry. Here we demonstrate
ion XOR and OR gates with electrochemical cells, and specifically, with two
wet-cell batteries. In parallel to vacuum tubes, the batteries were modified to
include a third, permeable and conductive mid electrode (the gate), which was
placed between the anode and cathode in order to affect the ion flow through
it. The key is to control the cell output with a much smaller biasing power, as
demonstrated here. A successful demonstration points to self-powered ion logic
gates.
