caa a22 4500 388076437 CHVBK 20180307125201.0 cr unu---uuuuu 161130e199911 xx s 000 0 eng 10.1557/S088376940005346X doi S088376940005346X pii (NATIONALLICENCE)cambridge-10.1557/S088376940005346X DeTeresa S.J. Materials for Advanced Flywheel Energy-Storage Devices [Elektronische Daten] [S.J. DeTeresa] Flywheels are mechanical devices that store kinetic energy in a rotating mass. A simple example is the potter's wheel. For energy storage and conversion, an efficient method to exchange energy with a flywheel device is by converting the energy between mechanical and electrical forms. Typically a flywheel designed to perform this type of energy exchange is a combination of a motor and a generator. Energy is transferred into the device for storage by using it as a motor to consume electrical energy and spin the mass. This energy can be recovered with an efficiency exceeding 80% by using the flywheel as an electrical generator. Although the concept of storing energy in a rotating mass is an ancient idea, the relatively recent advent of advanced fiber-composite materials offers the potential for improved energy storage and conversion using rotating electromechanical devices. The achievable energy density (energy/weight) of a simple flywheel design, such as that shown schematically in Figure 1, is proportional to the specific strength (strength/density) of the material. The particular type of composite flywheel shown in this figure is composed entirely of circumferentially wrapped fiber. Although other designs have been suggested and constructed, this version is the most common for energy-storage applications. As discussed in the earliest papers on the subject, such as the article by Post and Post, the proportionality between energy density and specific strength favors the use of fiber composites. The remarkable combination of mechanical properties and low density achieved with fiber composites has made them attractive and nearly essential for aerospace applications. Copyright © Materials Research Society 1999 MRS Bulletin Cambridge University Press 24/11(1999-11), 51-56 0883-7694 24:11<51 1999 24 MRS https://doi.org/10.1557/S088376940005346X text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1557/S088376940005346X text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- DeTeresa S.J. NATIONALLICENCE 773 0- MRS Bulletin Cambridge University Press 24/11(1999-11), 51-56 0883-7694 24:11<51 1999 24 MRS CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-cambridge