A single hybrid energy conversion and storage (HECS) cell of asymmetric Cobalt oxide (Co₃O₄)//N-doped reduced graphene oxide aerogel (N-rGO_AE) in 6 M KOH is proposed in this work. The Co₃O₄ serves as a photo-positive electrode material having an energy bang gap of 2.45 eV which can absorb all visible light region. Whilst, the N-rGO_AE as a negative electrode material can balance all the charges and excited electrons from the Co₃O₄ positive electrode due to its interconnected three-dimensional structure with nitrogen doping. Under red LED light source (627 nm = 1.98 eV), the current densities and specific capacitances of the as-fabricated asymmetric Co₃O₄//N-rGO_AE HECS cell are 1.4-fold higher than that under dark condition due to the photovoltaic effect. In addition, the charge storage mechanism and photo-charging behaviour of the Co₃O₄ electrode were also investigated by in situ electrochemical X-ray absorption spectroscopy and I-V characterization, respectively.