Electrochemical cell

Abstract

An electrochemical cell is described, which provides a reliable gas generation even under unfavorable environmental conditions and with significant changes in temperature and environment. Furthermore the cell has a long life time. The electrolyte of this electrochemical cell comprises at least one ionic liquid containing thiocyanate ions for the generation of hydrogen cyanide gas. Preferred substances for the composition of the electrolyte and for the provision of thiocyanate ions in the electrolyte are specified.

1 . An electrochemical cell ( 1 ) having an electrolyte ( 4 ), a generator electrode ( 5 ) and a counter electrode ( 3 ), wherein the electrolyte ( 4 ) comprises at least one ionic liquid and contains thiocyanate ions for generating hydrogen cyanide gas. 
     
     
         2 . An electrochemical cell ( 1 ) according to  claim 1 , wherein the electrolyte ( 4 ) comprises a mixture of at least two ionic fluids preferably from the group of 1-butyl-3-methylimidazolium trifluoromethanesulfonate, 1-ethyl-3-methylimidazolium trifluoromethanesulfonate and 1-ethyl-3-methylimidazolium thiocyanate. 
     
     
         3 . An electrochemical cell ( 1 ) according to  claim 1 , wherein the gas generating substance is a thiocyanate salt. 
     
     
         4 . An electrochemical cell ( 1 ) according to  claim 3 , wherein the thiocyanate salt is at least one of the group of NaSCN, KSCN, LiSCN, NH 4 SCN, NBu 4 SCN. 
     
     
         5 . An electrochemical cell ( 1 ) according to  claim 1 , wherein the generator electrode ( 5 ) consists of a noble metal, preferably of one of the group of gold, rhodium, iridium, palladium and platinum. 
     
     
         6 . An electrochemical cell ( 1 ) according to  claim 5 , wherein the generator electrode ( 5 ) is a noble metal wire mesh and preferably a platinum wire mesh. 
     
     
         7 . An electrochemical cell ( 1 ) according to  claim 5 , wherein the generator electrode ( 5 ) is a PTFE gas diffusion membrane coated on one side with a noble metal. 
     
     
         8 . An electrochemical cell ( 1 ) according to  claim 1 , wherein it is sealed to the outside by a PTFE gas diffusion membrane ( 7 ), which is permeable to the generated hydrogen cyanide gas. 
     
     
         9 . An electrochemical cell ( 1 ) according to  claim 1 , wherein the ionic liquid ( 4 ) is provided in a housing or container ( 2 ) comprising glass fiber layers. 
     
     
         10 . An electrochemical cell ( 1 ) according to  claim 1 , wherein the counter electrode ( 3 ) essentially consists of platinum. 
     
     
         11 . An electrochemical cell ( 1 ) according to  claim 10 , wherein the counter electrode ( 2 ) is a PTFE coated with platinum.