Dubasova V.S.,Research and Process Design Institute of Electrocarbon Products |
Mikhailova V.A.,Research and Process Design Institute of Electrocarbon Products |
Nikolenko A.F.,Research and Process Design Institute of Electrocarbon Products |
Ponomareva T.A.,Research and Process Design Institute of Electrocarbon Products |
And 2 more authors.
Russian Journal of Electrochemistry | Year: 2013
The effect of structural and surface properties of carbon anodic materials based on natural graphite of the Taiginka Deposit obtained using different technologies on the capacity characteristics of the negative electrode of a lithium-ion battery is studied. It is shown that the key factors determining the value of irreversible capacity of the negative electrode in the first cycle are the value of graphite specific surface area, the state of the surface, in particular, the content of disordered carbon, and functional groups on the surface of graphite particles, and also the composition of the active electrode layer. A change in the specific surface area value and content of functional groups is due to the efficiency of the pyrocarbon coating in the case of samples subjected to milling on vibration and cavitation mills, and also of finely dispersed samples obtained by milling on a jet mill. The observed decrease in the specific surface irreversible capacity at an increase in the specific surface area of carbon is apparently caused by inhomogeneity of the latter and nonparticipation of its microporous part in formation of the solid-phase surface passivating film. The minimum irreversible specific capacity of electrodes of the studied natural graphite for the optimum electrode material composition was about 20 mA h/g or 6%. The specific surface capacity changed as dependent on the value and state of the graphite sample surface more than threefold (from 2.5 to 7.7 mA h/m2) and by an order of magnitude at an additional change in the electrode composition (from 2.5 to 20.3 mA h/m2). © 2013 Pleiades Publishing, Ltd.