Natural polymers offer several benefits as battery components, such as wide availability, biodegradability, non-leakage, stability in solid form, ease of processing, electrochemical stability, and low production costs. On the contrary, conductive polymers can enhance the battery's electrochemical performance, improving factors like energy storage capacity, cycling stability, and charge/discharge rates. Thus, combining these two types of materials can yield desirable properties. In this research, thin polymer films are produced based on cellulose using the solution casting method. Polyaniline (PANI) is then mixed with cellulose in various weight ratios. The electrochemical characteristics of the prepared electrolytes are analyzed, revealing that the addition of PANI increases ionic conductivity through creating voids and benefiting from the conductive polymers' high dielectric constant. The prepared electrolytes demonstrate impressive ionic conductivity (approximate to 10-3 S cm-1 upon incorporating PANI), remarkable discharge capacity, consistent cycling stability, outstanding electrochemical performance with a stability window exceeding 4.5 V, and a good Li+ transference number spanning from 0.44 to 0.76.