High energy density aqueous zinc–benzoquinone batteries enabled by carbon cloth with multiple anchoring effects

Abstract

Benzoquinone (BQ) is a desirable cathode for aqueous rechargeable batteries because of its high theoretical capacity and low cost. However, its application is seriously hindered by the high solubility of its discharge product in electrolytes, leading to rapid capacity decay. Here, we report a highly pyridine- and pyrrole-N-doped carbon cloth (NCC) with hierarchical pores as a promising host to anchor BQ and its discharge products. The resultant cathode (BQ-NCC) exhibits an ultrahigh initial capacity of 489 mA h g_BQ⁻¹ (excluding the capacity contribution of NCC) at 0.1 A g⁻¹ and a long cycle life with a high capacity retention of 90.4% at 0.5 A g⁻¹ after 500 cycles. Furthermore, a pouch-type cell with a capacity of ∼0.23 A h delivers an energy density of 136.1 W h kg⁻¹ based on the total mass of BQ-NCC and Zn foil. Our study provides a novel strategy to construct high-performance aqueous Zn-ion batteries for potential practical applications.