Long-lifespan Polyanionic Organic Cathodes for Highly Efficient Organic Sodium-ion Batteries.

An organic Na-ion battery is reported with a polyanionic 9,10-anthraquinone-2,6-disulfonate (Na AQ26DS, 130 mAh g ) cathode and the Na-intercalated state (Na TP) of sodium terephthalate (Na TP, 255 mAh g ) as the anode. The resulting full cells deliver the maximum discharge capacity of 131 mAh g in 0.5-3.