Structure and electrochemical property of pyrocarbon-based negative electrode prepared from carbonized wood by chemical vapor infiltration

The negative electrodes for lithium-ion rechargeable battery were prepared by pressure-pulsed chemical vapor infiltration of pyrolytic carbon (pyrocarbon) into two sorts of conductive porous preforms, that is, the carbonized wood (A) and the TiN-coated wood (B). The electrodes had the three-dimensionally continuous current paths in the pyrocarbon-based anodes without the organic binders and the additional conductive fillers. The pyrocarbon in sample (A) had the relatively high crystallinity, whereas the pyrocarbon in sample (B) was disordered. The capacity of pyrocarbon in sample (B) was 442 mAhg -1 per mass of pyrocarbon at a current density of 30 mAg -1 , and 80 % of the capacity was maintained even at 960 mA g -1 . The capacity of pyrocarbon in sample (A) was estimated at ∼300 mAhg -1 , which was lower than that of sample (B). However, sample (A) showed higher coulombic efficiency at first cycle (i.e. 87 %) than that of sample (B).