Preparation and characterization of polymer blend electrolyte membranes based on lithium acetate‐complexed carboxymethyl cellulose (CMC) and carboxymethyl chitosan (CMCh) blend

• Published in: Polymer engineering and science 2024-02, Vol.64 (2), p.761-778
• Main Authors: Ndruru, Sun Theo Constan Lotebulo, Marlina, Anita, Nugroho, Bangun Satrio, Pramono, Edi, Sabrina, Qolby, Yulianti, Evi, Arcana, I Made, Wahyuningrum, Deana
• Format: Article
• Language: English
• Subjects: Carboxymethyl cellulose; carboxymethyl chitosan; Cellulose; Chitosan; Decomposition; Electric potential; Electrolytes; Ion currents; ionic conductivity; Lithium; Lithium-ion batteries; Mechanical properties; Membranes; Molten salt electrolytes; polymer blend electrolyte membranes; Polymer blends; Polymers; Solid electrolytes; Thermal stability; Voltage
• ISSN: 0032-3888; 1548-2634
• DOI: 10.1002/pen.26582

This work aimed to prepare solid polymer blend electrolytes based on carboxymethyl cellulose (CMC) and carboxymethyl chitosan (CMCh) complexed with lithium acetate (LiCH3COO) for lithium‐ion batteries application. The solid polymer blend electrolytes of LiCH3COO‐complexed CMC/CMCh (50/50) polymer blend electrolyte were prepared by using the casting solution technique, where various weight percentages of LiCH3COO were mixed into CMC/CMCh (50/50) blend as host polymer. Solid polymer blend electrolytes of CMC/CMCh + 30wt% LiCH3COO had the highest ionic conductivity as much as 2.24 × 10−5 S cm−1 among others. The CMC/CMCh blend (50/50) + 30wt% LiCH3COO degraded at temperature interval 256–473°C. Linear sweep voltammetry method shows that CMC/CMCh (50/50) + 30wt% LiCH3COO reached a decomposition voltage around 2.54 V, while CMC/CMCh (50/50) + 10wt% LiCH3COO was decomposed at a lower voltage around 1.55 V. Based on the tLi+ transference number measurement appeared that the initial and final current values of 0.84 for the CMC/CMCh (50/50) + 30wt% LiCH3COO is higher than that of the CMC/CMCh (50/50) + 10wt% LiCH3COO (0.8). Based on the results obtained, it can be concluded that the CMC/CMCh blend (50/50) + 30wt% LiCH3COO meets the minimum requirements for the main parameters of ion conductivity and thermal stability as a solid electrolyte polymer membrane but needs improvement and attention to its mechanical properties. Highlights CMC and carboxymethyl chitosan (CMCh) have polar groups for ionic conduction. The CMC/CMCh blend (50/50) + 30wt% LiCH3COO has good ionic conductivity of 2.24 × 10−5 S cm−1. The CMC/CMCh blend (50/50) + 30wt% LiCH3COO has high thermal stability 256–473°C. The CMC/CMCh blend (50/50) + 30wt% LiCH3COO has high decomposition voltage around 2.54 V. The CMC/CMCh blend (50/50) + 30wt% LiCH3COO has higher tLi+ transference number (0.84). The solid polymer electrolyte membranes based on carboxymethyl cellulose (CMC)/carboxymethyl chitosan (CMCh) blend (50/50) complexed to LiCH3COO salt had been successfully studied and characterized. CMC/CMCh blend (50/50) + 30wt% LiCH3COO exhibited the highest ionic conductivity as much as 2.24 × 10–5 S cm−1, with free ion percentage obtained as much as 88.62%. The existence of the 30wt% LiCH3COO salt addition in the CMC/CMCh (50/50)‐complexed to LiCH3COO salt solid polymer blend membrane can decrease the tensile strength drastically as much as 1.76 MPa, and vice versa increase the elongation at break significant