Space-confined construction of nitrogen-rich cobalt porphyrin-derived nanoparticulates anchored on activated carbon for high-current lithium thionyl chloride battery

Abstract Primary batteries based on lithium metal anodes have been attracting increasing attention due to their high capacity and energy density, but the implementation high-current of battery still faces many challenges, such as low reaction rate of SOCl2 and large impedance. Space-confined construction of nitrogen-rich cobalt porphyrin-derived nanoparticulates anchored on functional-activated carbon (NCA) composites were prepared by in situ solid phase synthesis as catalysts of carbon cathode to address these issues. On the molecular level, the π-π conjugate system is further enhanced by forming C–O–Co bond between the Co atoms of cobalt porphyrin derivatives and the oxygen-containing functional groups of functional-activated carbon. Significantly, the resulting NCA composites exhibit the longest high-current (above 25 mA/cm2) discharge time, up to 37 min, and the capacity is about 19.18 mAh, accounting for 88.5% of its total capacity. Meanwhile, the internal resistance of the battery catalyzed by the NCA composites (24.06 Ω) is 0.40 times lower than that without catalysts, and the reduction peak of cyclic voltammetry is the largest about 2.357 V, showing that the electrode with NCA composites has good catalytic activity. All this is due to the fact that the carrier activated carbon of the NCA composites reduces the internal resistance of the battery by regulating the porosity of the carbon cathode, and the loaded CoTAP nanoparticulates improve the reduction rate of SOCl2.