Abstract
The solid-state diffusion of lithium ion in carbon was directly investigated in single spherical particles of graphitized mesocarbon microbeads (MCMB, Osaka Gas Co.). In order to achieve electrochemical measurements focusing on a single particle, a molybdenum-filament microelectrode was maneuvered to make electrical contact with a single MCMB placed in an organic solvent mixture containing lithium ions as an electrolyte. This novel microelectrode technique gives electrochemical information about a MCMB particle, itself, without any dilution with additives such as organic binders. The chemical diffusion coefficient (D) of lithium ion was determined from potential-step chronoamperograms assuming spherical diffusion of lithium ions in the MCMB particle. The values of D were found to change the order between 10-9 and 10-11 cm2/s depending on the electrode potential. Plots of D showed pronounced minima at the potentials where the transformation of staging level of lithium intercalation compounds occurred.
Original language | English |
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Pages (from-to) | 10-12 |
Number of pages | 3 |
Journal | Electrochemical and Solid-State Letters |
Volume | 1 |
Issue number | 1 |
DOIs | |
Publication status | Published - 1998 Jul |
ASJC Scopus subject areas
- Chemical Engineering(all)
- Materials Science(all)
- Physical and Theoretical Chemistry
- Electrochemistry
- Electrical and Electronic Engineering