Calcium terephthalate/graphite composites as anode materials for lithium-ion batteries

We have reported a conjugated carbonyl organic calcium terephthalate (CaTPA)-based organic/inorganic composite as anode material for lithium-ion batteries. The bulk CaTPA presents a low electronic conductivity leading to a large electrochemical polarization during charge/discharge process. Graphite is chosen as a conductive additive to improve its electrochemical performance via ball milling. The effect of graphite amount on the electrochemical properties of CaTPA is investigated. The composite with the weight ratio of 100:10 (CaTPA/graphite) (named CaTPAG10) shows the smallest electrochemical polarization, largest Li+ diffusion coefficient, and best rate capability, delivering discharge capacity of 233 mAhg−1 at current rate of 0.1 C and discharge voltage plateau at ~0.8 V. CaTPAG10 further exhibits good cycling performance, from 169 mAhg−1 down to 161 mAhg−1 after 50 cycles, giving a capacity retention of 95 % at 2 C compared with that of 89 % for the pristine CaTPA. To explore commercial application of CaTPA, a full cell with LiCoO2 and CaTPAG10 as a cathode and an anode material, respectively, is tested. The full cell reveals an operational voltage at 2.8 V and reversible capacity of about 138 mAhg−1 at 1 C.