Graphite intercalation compounds (GICs) containing bis(trifluoromethanesulfonyl) imide, are prepared for the first time by electrochemical oxidation of graphite. Electrolytes with nitromethane and ethyl methyl sulfone are used to prepare GICs up to stage 1. The potential-charge curves under galvanostatic or pulse-charge mode show transitions associated with GIC staging, and charge and discharge capacities and charging efficiencies are reported at transition points. The stage 1 GICs have not been prepared before and rapidly decompose in air in the electrolyte. GIC gallery heights and stages are determined by powder X-ray diffraction, and the stage 1 composition is determined by thermogravimetric analysis. Structural and electrochemical properties are compared with those for related GICs. © 2001 The Electrochemical Society. All rights reserved.