The mechanisms for the high capacity of lithium insertion in low-temperature pyrolytic carbons are not fully understood though several models have been proposed. None of the existing models considers the reversible crystalline structural changes within a graphene layer in the discharge-charge processes. In this report, low-temperature pyrolytic phenolic resin and lithium ion cells made of it are characterized by Raman spectroscopy, XRD and elemental analysis as well as discharge/charge measurements. The linear relation is confirmed between the specific capacity of the low-temperature pyrolytic carbon and its H/C atomic ratio after eliminating the influence of the crystallite size to the capacity. It is found that the evolution of the Raman spectrum of the pyrolytic carbon electrode upon discharge and charges quite different from that of the other forms of carbonaceous electrodes. Based on the characteristic Raman spectra and the discharge-charge curves of the carbon electrode, a breaking-recovery model of the weak C ... H bond is suggested for the lithium insertion/extraction processes in the low-temperature pyrolytic carbon electrodes.