Electrochemical insertion of lithium into carbonaceous materials derived from pyrolyzed polyparaphenylene: Effects of the pyrolysis time

In order to optimise the thermal treatment of PPP at 700 degrees C, we repo rt on the electrochemical studies using solid polymer electrolytes composed of polyethylene oxide (PEO) and LiClO4 of the insertion of lithium ions in to PPP pyrolyzed at 700 degrees C in argon atmosphere during increasing pyr olysis times (0.5; 1, 2 and 6 hours). The electrochemical measurements reveal that two parameters are necessary t o improve the affinity of these materials for lithium : i) the density of c rosslinking (or the lateral extension of the graphene sheets for the longes t pyrolysis times) must be large, ii) a high molar ratio H/C.