Practical lithium-organic batteries enabled by an n-type conducting polymer

Organic batteries using abundant and recyclable organic electrode materials provide a sustainable and environmentally friendly alternative to commercial lithium-ion batteries^1-5, which rely on resource-limited mineral-derived inorganic electrode materials^6-8. However, the practical use of organic batteries has been severely hindered by the intrinsic insulation and dissolution of organic electrode materials^9,10. Here we report practical organic batteries using an n-type conducting polymer cathode, poly(benzodifurandione) (PBFDO), which exhibits excellent mixed ionic and electronic transport and low solubility. The PBFDO cathode maintains its n-doped state throughout the electrochemical processes and exhibits stable and reversible redox characteristics, high electrical conductivities and significant lithium-ion diffusion coefficients, without the need for additional conductive additives. Consequently, ultrahigh-mass-loading polymer cathodes, with mass loadings up to 206 mg cm^-2, are realized, delivering a high areal capacity of 42 mAh cm^-2 and demonstrating robust cycling stability. Furthermore, practical 2.5 Ah lithium-organic pouch cells were fabricated, achieving an impressive energy density of 255 Wh kg^-1. Notably, the conducting polymer cathode operates efficiently over a wide temperature range from -70 °C to 80 °C and demonstrates excellent flexibility and safety, marking considerable potential for applications in extreme conditions and wearable electronics.