Source : Webster's Revised Unabridged Dictionary (1913)

Electropoion \E*lec`tro*poi"on\, n., or Electropoion fluid
\Electropoion fluid\ [NL.; electro- + Gr. poiw^n, p. pr. of
   poiei^n to make.] (Elec.)
   An exciting and depolarizing acid solution used in certain
   cells or batteries, as the Grenet battery. Electropoion is
   best prepared by mixing one gallon of concentrated sulphuric
   acid diluted with three gallons of water, with a solution of
   six pounds of potassium bichromate in two gallons of boiling
   water. It should be used cold.