Two model systems were defined to identify the impact of morphology (particle size, shape and relative orientation) on electrochemical performance for graphite electrodes in the Li-ion battery. In one, a Timrex KS44 graphite powder was sieved into three fractions: 0-15, 15-25 and 25-45 mum. Particle shape and atomic structure were essentially the same for all three fractions. The smallest particles gave the poorest cycling behaviour. Lithium content in fully intercalated electrodes from the three fractions was determined from DSC measurements. It was found to be almost the same in all three cases. A natural graphite sample was also sorted into two different fractions: one with flat, flaky grains and the other with rounder grains. Both fractions had closely similar atomic structures and particle-size distributions. No differences could be discerned in electrochemical cycling behaviour. The results are discussed in the light of the impact of electrode preparation.
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