Polyvinyl alcohol/nano-carbon colloid (PCC) was prepared through a simple physical mixture process. Both fully charge-discharge and insufficient charge tests were carried out to demonstrate the positive effects of PCC on the electrical storage capability of the negative electrode of lead acid battery. Cyclic voltammetry, steady polarization and electrochemical impedance spectroscopy were used to characterize the influences of PCC on the electrochemical behaviors of negative electrode in the lead acid battery. Experiment results demonstrate that PCC has positive effect on inhibiting PbSO growth and increasing the HER overpotential, thus the lead acid battery with PCC shows the enhanced charge acceptance and stable discharge capacities under insufficient charge test. This paper opens a new way for enhancing the performance of lead acid battery without changing the traditional structure and design of lead acid battery.