Covalently organic derivatization of [Li(+)@C60]PF6(-) to obtain Li(+)-encapsulated PCBM, [Li(+)@PCBM]PF6(-), is described. Synthetic procedures, electrochemical properties, light absorption properties, details of isomerization from [5,6]- to [6,6]-isomer, and X-ray crystal structure of [Li(+)@PCBM]PF6(-) are discussed.