Dependence of the morphology of graphitic electrodes on the electrochemical intercalation of lithium ions

摘要: We have studied the effects of several parameters that influence electrochemical intercalation lithium ions into various carbonaceous materials: massive samples pyrographite PGCCL (Le Carbone Lorraine), bulky pitch-based graphitized carbon fibres P100-S (Amoco) and divided natural graphite powder UF4 Lorraine). The Li+ has been achieved in electrolytic solutions composed a solvent, ethylene carbonate conducting salt, LiClO4. shown previously such an electrolyte allows unsolvated up to richest stage-I LiC6 composition without apparent solvent decomposition. behaviour electrodes electrolytes was followed either by chronopotentiometry (galvanostatic charge/discharge cycles) or cyclic voltammetry. use micro-computers, able conduct experiments imposition charge potential steps cell relaxations, allowed obtain data on kinetics intercalation. graphitic electrode is strongly dependent its morphology. Moreover, decrease size crystalline domains during prolongated cyclings particularly samples. Such grinding obviously positive effect performances characterized noticeable increase maximum x reached (x refers LixC6 composition). It appears also poly(vinylidene difluoride) (PVDF) leads side reactions negative electrodes.