Electrochemical characterization of lithium 4,4′-tolane-dicarboxylate for use as a negative electrode in Li-ion batteries

Lithium 4,4′-tolane-dicarboxylate has been synthesized and examined for use as a negative electrode material in lithium ion batteries. Cycling studies in Swagelok cells, using lithium as a counter electrode, show a reversible capacity of ∼200 mAh g−1 at ∼0.65 V and minimal discharge/charge polarization (∼15 mV). XRD and SEM analyses reveal that the material crystallizes in two different ways depending on the type of solvent used in the synthesis. The changes in structural packing with methanol or ethanol dramatically affect the capacity of the material leading to electrodes that are able to intercalate almost two vs. one Li per unit formula, respectively.