Electrochemical lithium insertion behavior of boron-containing carbons was studied by constant-current potentiometry. The boron-containing carbons were prepared by pyrolyzing a phenolic resin chemically bonded with boron atoms, which was synthesized via an esterification reaction of the phenol hydroxyl groups by boric acid. It was found that the as-prepared boron-containing carbons at pyrolysis temperatures higher than 700 degreesC could accommodate more lithium species than the corresponding boron-free carbon, yet those prepared at pyrolysis temperatures lower than 700 degreesC accommodated less lithium than the boron-free control sample. In particular, the boron-containing carbon prepared at 900 degreesC exhibited a capacity higher than the theoretical value of graphite and reasonable charge/discharge voltage curves. The elemental, X-ray diffractometric and X-ray photoelectron spectroscopic analysis results indicated that at the pyrolysis temperature of 500 degreesC, the lithium accommodation capacity of the pyrolytic carbon was mainly dependent on its residual hydrogen content, rather than the boron content. However, when pyrolyzed at 900 degreesC, more boron atoms were bonded with carbon atoms and introduced to the graphene microcrystallite structure. Therefore, boron atoms exerted a considerable effect on the lithium insertion behavior and more lithium species were reversibly inserted into the carbon matrix due to the electron-deficient nature of boron atoms.