Standard Article

Technical characteristics of PEM electrochemical capacitors


Other energy conversion related topics

  1. J. A. Kosek,
  2. B. M. Dweik,
  3. A. B. LaConti

Published Online: 15 DEC 2010

DOI: 10.1002/9780470974001.f207057

Handbook of Fuel Cells

Handbook of Fuel Cells

How to Cite

Kosek, J. A., Dweik, B. M. and LaConti, A. B. 2010. Technical characteristics of PEM electrochemical capacitors. Handbook of Fuel Cells. .

Author Information

  1. Giner Electrochemical Systems, Newton, MA, USA

Publication History

  1. Published Online: 15 DEC 2010


Electrochemical capacitors, also known as supercapacitors and ultracapacitors, are capable of very high charge storage. Operating on both pseudocapacitance and double-layer capacitance, they have demonstrated high capacitance compared to electrolytic and electrostatic capacitors. Electrochemical capacitors have been fabricated from a wide variety of materials, including precious metal oxides and transition metal nitrides as the positive and negative electrode materials, and organic, aqueous, and solid polymer electrolytes. These capacitors have been demonstrated to provide as high as 4 F cm−2 of active electrode area. Individual cell voltages range from 1 V cell−1 for aqueous-based electrolytes, up to 2.5–4 V cell−1 for organic electrolytes. This publication describes the various types of capacitors, and also compares electrochemical capacitors to batteries. Recent work in the area of electrochemical capacitors is reviewed. The fabrication and operation of all-solid ionomer or proton-exchange membrane electrochemical capacitor stacks is targeted for special attention. These devices have been fabricated in a wide range of sizes, ranging from 350-cell stacks with active areas of 2 cm2, to 60-cell stacks with active areas of 450 cm2 cell−1. The discharge characteristics and energy storage properties of these devices are described. Specific applications of various capacitor stacks are discussed.


  • electrochemical capacitor;
  • all solid ionomer capacitor;
  • supercapacitor;
  • ultracapacitor;
  • capacitor (comparison with batteries)