ES1 SENSOR: SMALLEST ELECTROCHEMICAL SENSOR IN THE WORLD SOLID POLYMER ELECTROLYTE GAS SENSORS
from VOC sensing to long-life oxygen gas sensors
Solid polymer electrolyte (SPE) gas sensors offer flexibility in design and size, because the basic sensor design is dry and contains no liquid electrolytes. Liquid electrolyte gas sensors, also known as wet electrochemical cells, are used in many applications ranging from automotive (fuel usage optimization) over industrial (safety) and to emission control (surveillance). Because of the wet current carrying electrolyte, the mechanical design is essential for operation and lifetime of the cell. Over the last 20-30 years certain popular wet electrochemical cell designs have become standard – like the 4-series (diameter 20 mm) for handheld gas analyzers and the 7-series (diameter 32 mm) for stationary gas analyzers. The concept of a dry electrochemical cell based on a solid polymer electrolyte challenges not only the design restrictions of the gas sensor, but also the traditional applications for electrochemical cells.