Hydrophilic polyaniline/graphene oxide composite promoting electron and ion transfer in positive electrode of lead-carbon battery

Sluggish ions and electron transport caused by high polarization result in low utilization efficiency of positive active materials (PAMs) in lead-carbon batteries (LCBs). Hydrophilic polyaniline/graphene oxide (PANI/GO) composites are prepared via a facile oxidation polymerization approach and incorporated as positive additives to regulate electron and ion transfer in positive electrodes of LCBs. The effects of PANI/GO additives on the characteristics of substances transformation, crystal size, and utilization efficiency of PAMs during curing, formation, and cycling stages are systematically examined. The synergistic features of hydrophilicity, conductivity, and pseudo-capacitance in PANI/GO composite provide an efficient conductive network and serve as storage medium for HSO 4 − ions, thereby regulating the local environment and substantially accelerating electron/ion transfer within positive plates. The LCBs with 0.45 wt% PANI/GO deliver the highest initial discharge capacity of 3.55 Ah at 0.1 C, which is 63.5 % improvement over the blank sample. The discharge capacity of 2.15 Ah could be maintained at 1 C rate and the capacity retention remains as high as 98.8 % after 100 cycles, highlighting the outstanding rate capability and cycling stability. This study provides an alternative for the development of high-efficiency positive additives for LCBs in energy storage applications.