In order to develop an alternate material for energy storage devices like batteries, this research is being done to create polymer electrolytes based on cellulose as natural polymer. Natural polymers as battery components have a number of advantages, including availability, biodegradability, unleakage, stable form, superior process, electrochemical stability, and low cost. In this study, polymer electrolytes based on cellulose have been synthesized by solution casting to prepare a thin polymer films. The solid or gel state of the polymer electrolyte and the kind of cross-linker (citric acid and polyvinyl alcohol) on the electrochemical properties of electrolyte have been investigated. Results showed that the crosslinking has improved ionic conductivity of solid and gel polymer electrolytes. Gel polymer electrolyte (GPE) cross-linked by 1 % citric acid exhibited higher ionic conductivities (up to 5.58 × 10−4 S cm−1 at room temperature) than other polymer electrolytes. The corresponding GPE presented a high lithium-ion transference number of 0.65, high electrochemical stability, and good specific capacity (212.41 mAh g−1 at 0.2C of LiCoO2/GPE-Ce-CA1/graphite). All these features prove that the GPE-Ce-CA1/graphite has great potential for the application of lithium-ion batteries. © 2025 Elsevier B.V., All rights reserved.