Written response by Prof. Andrew Cruden, Professor of Energy Technology & Co-Director EPSRC CDT in Energy Storage and its Applications, Head of Energy Technology Research Group, Engineering Sciences, ¾ÅÉ«ÊÓƵ, Dr Harriet Kimpton MRSC,PhD Researcher, ESPRC CDT for Energy Storage and its Applications and Susan Sun, MPhys Physics, Postgraduate research student.