Li-ion batteries (LIBs) contribute prominently to the energy storage field due to their acceptable cyclibility and higher energy density [1]. However the traditional inorganic based electrode materials suffering due to the constraint imposed by their structural aspects and scarcity of resources. Hence the focus is on the alternative electrode materials which could be synthesized from renewable sources via eco-friendly processes [1,2]. Recently redox active conjugated carbonyl compounds have gained great attention due to their structural diversity, rate capability and ease of synthesis [1]. In this context we report, lithium biphenyl-3,3',4,4'-tetracarboxylate (Li₄-BPTC)  as a potential anode for  both Li-ion and Na-ion batteries for the first time. Li₄-BPTC electrode delivered a stable capacity and as well as good rate performance in both Li and Na half cells. Reversible capacities of 92 mAh g^-1 after 100 cycles (vs. Li⁺/Li) and 107 mAh g^-1 after 200 cycles (vs. Na⁺/Na) were observed at a current density of 160 mA g^-1. The exchange of Li-ion in the Li₄-BPTC by Na-ion during electrochemical cycling against Na⁺/Na was confirmed by ICP-OES and XPS analysis.

References:

1. Song Z, Zhou H. Towards sustainable and versatile energy storage devices: an overview of organic electrode materials. Energy Environ Sci., 2013 (6) 2280-301.

2. Renault S, Brandell D, Gustafsson T, Edström K. Improving the electrochemical performance of organic Li-ion battery electrodes. Chem Commun., 2013 (49) 1945-7.