‘Massless’ Energy - Structural Power Composites

Dr Emile S. Greenhalgh CEng FIMMM,

Imperial College London, UK (e.greenhalgh@imperial.ac.uk)

Notable contributions from Dr Jesper Ankersen, Prof Leif Asp, Prof A Bismarck, Tony

Carlsson, Dr Quentin Fontana, Prof A. Kucernak, Dr Mayur Mistry, Dr Sang Nguyen,

Dr Sherry Qian, Prof M. Shaffer, Dr J Steinke and Dr Natasha Shirshova

Weight and volume are at a premium in many applications, and any material that does not

contribute to the load-carrying capacity is structurally parasitic. Whilst current engineering design

pursues optimisation of the individual components the alternative is to formulate multifunctional

materials which can perform two or more functions simultaneously. The key here is not simply to

bind two disparate components together (such as in a sandwich structure), but to produce a single

coherent material that inherently performs both roles. Such materials offer considerable savings in

system mass/volume and thus significant performance benefits. This design methodology is in its

infancy and faces significant design and material synthesis challenges, requiring the combination

of disparate and often cross-cutting phenomena.

The presentation will focus on the research on structural power composites conducted by the

multidisciplinary group at Imperial College London, but will include developments from the EU

Funded STORAGE programme, particularly those by Swerea SICOMP in structural capacitors and

batteries. The research has entailed enhancement of the surface area of the reinforcement carbon

fibres (electrodes) through various routes. This includes carbon aerogel (CAG) reinforcement of

carbon fibres which has the potential to have a significant impact on conventional composites. In

parallel, multifunctional matrices (solid electrolytes) have been developed in which the balance

between mechanical and electrical performance have been tailored. These constituents have been

brought together to produce a range of structural power composites, the electrical and

mechanical performance of which are presented here. Finally, the engineering methodologies for

utilising these new materials and the subsequent demonstration as multifunctional automotive

components is presented. Further details of this work can be found here

(www3.imperial.ac.uk/structuralpowerstorage) and the material can be seen at

(www.youtube.com/watch?v=j2qpDPcO7vg). Although there are still considerable engineering

challenges which need to be addressed, such as durability and manufacturability, it is anticipated

that structural power materials will revolutionise transport applications and mobile devices.

Dr Emile S. Greenhalgh is a Reader in Composite Materials and has worked in polymer composites

for over 26 years. In particular, he is internationally recognised as the expert in failure analysis

(fractography) of composites. Finally, he leads the structural power research at Imperial College

and headed the European Union FP7 programme (STORAGE) on structural power materials for

hybrid cars.