PhD Thesis - Cranfield University

Chapter 2
(a) From US Patent 2800616 (1957) (b) From US Patent 3288641 (1966)
(c) From US Patent 3536963 (1970) (d) Modern ultracapacitor construction (2002)
Figure 2.4 Evolution of the EDLC technology
(a) Patent by H.I Becker, (b) Patent by R. A. Rightmire, (c) Patent by D.L. Boos, (d) Modern ultracapacitor
(Maxwell-Montena)
The terms ‘Supercapacitor’, ‘Ultracapacitor’ and ‘Electrochemical Double Layer Capacitor’
have been used indiscriminately in literature in reference to high capacitance devices.
Huggins [47] identified this uncertainly in terminology and made a distinction between these
type of capacitors in terms of their storage mechanisms and redox pseudo-capacitance.
However, it is generally recognised that these terms are interchangeable depending on the
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