Page 11 - PERIODIC 2017
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As             pure as the




                                driven snow




                                Lithium-Ion Batteries: a personal perspective

                                Phil Wiseman


            Research at Oxford Chemistry led to the development of the Li-ion battery,
            ubiquitous today as the power source for mobile phones, laptops, electric
            vehicles and many other devices.   This ground-breaking discovery was made
            at the Inorganic Chemistry Laboratory and is commemorated by a blue plaque
            outside the lab.  Dr Phil Wiseman, one of the original researchers, tells his story
            for Periodic.
                                                                That solid state chemistry became active in the department
            Prelude                                             was primarily due to one man: Professor J Stuart Anderson.
            Peter Dickens’ lab did look                         JS was a walking encyclopaedia on the subject. In his seminal
            different. As you hurried through                   textbook with Emeléus, the tungsten bronzes stand centre-
            the archway to ICL lectures                         stage as grossly non-stoichiometric compounds, Na WO ,
                                                                                                            3
                                                                                                        x
            in the late 1960s, glancing to                      the host WO  chains templated according to the rotundity of
                                                                          3
            the left through the window of                      the guest, their shiny chameleon-coats reflecting a varying
            G3, you could see the copper                        electron exchange to the host. But from his unpopular
            windings of the backs of the                        lectures, we learnt little. In any spare moment, he suggested
            Variac transformers that controlled the furnaces; it was a   we looked down the body diagonal of a cube.
            high temperature world where thermodynamics ruled.
            More familiar was the teaching lab above, first encountered   In 1969, starting a Part II was a rite of passage. It was much
            the previous year in the Practical Entrance Exam, where   more common to work for your college tutor and the first time
            the arch-braced beams seemed to hold far more secrets   you could call each other by Christian names. For storage
            than the copper ammine complex we analysed. Later, Peter   purposes, I brought along some of my grandfather’s cedar
            would give a lecture illustrated with a box of samples he was   cigar boxes. One of these was immediately commandeered by
            working on called tungsten bronzes: their mysterious look   Peter to re-house his bronze samples; it travelled the world.
            spurred curiosity.                                  Entering G3, the only obvious nod to safety was a World
                                                                War II gas mask hanging behind the door. To the right, Stan
            First synthesised in 1824, for 100 years these metallic   Whittingham’s microbalance was embedded in the original
            misfits were condemned to the dogma of the day:     front wall – Stan had recently left for a Post Doc in America
            pNa O.qWO .WO . Mind your ps and qs - small integers only!   and is a key figure in the lithium battery story. During his
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            Fortunately, Nature had ruled its own diffraction gratings.   Part II year, he was the first person to synthesise oxide bronzes
            Scribbling on the tables at the Café Lutz, Munich in 1913, von   at Oxford.
            Laue’s team speculated how the new X-rays might interact
            with crystals. Despite Bragg junior’s               Peter had inherited his tutor’s (Jack Linnett) style of graduate
            corrections, a sodium chloride                                      supervision where ‘distinguished
            molecule stretching to infinity                                     visitors were introduced to his research
            created a divide among chemists                                     students, no matter how junior, as if
            that still partially exists. At Oxford,                             they were established collaborators’;
            Marcus ‘Tiny’ Powell pioneered                                      and he  certainly enjoyed analysing what
            X-ray crystallography. A fantastic                                  made someone tick. His research ‘family
            linguist, he illuminated host/                                      tree’ included Robert Bunsen who was
            guest inclusion structures and,                                     adamant there were two distinct classes
            in a case of science imitating art,                                 of scientist: ‘first, those who work at
            we synthesised his nickel cyanide                                   enlarging the boundaries of knowledge,
            benzene clathrate within the oak-                                   and, secondly, those who apply that
            framed cavity of the teaching lab.                                  knowledge to useful ends’. Bunsen
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                                                                                                 Periodic
                                                            The Magazine of the Department of Chemistry
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