ELECTROLYTE POLYMER MEMBRANES BASED ON CHITOSAN/LIOH/SUCCINIC ACID CROSSLINKER FOR LITHIUM - ION BATTERY APPLICATION

• Main Author: Shafira Setiawati, Santy
• Format: Theses
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/71560
• Institution: Institut Teknologi Bandung

Batteries are an important component in building electronic devices. Batteries that are currently widely used in electronic devices are lithium-ion batteries, because they are environmentally friendly. However, the main constituent component of lithium-ion batteries has been a liquid electrolyte, for example lithium-sulfur, which is risky and dangerous in use. Therefore, it is necessary to develop alternatives to the liquid electrolyte. Many developments have been carried out, namely through the formation of solid electrolytes with a thin and environmentally friendly form. Modifications that have been developed to date are the formation of solid electrolytes based on polymers that are environmentally friendly and derived from natural materials, one of which is using chitosan-based polymers. However, this pure chitosan-based solid electrolyte biopolymer still has weaknesses, namely ionic conductivity/conduction and mechanical properties that are still relatively low. Therefore, other modifications are needed related to chitosan-based solid electrolyte polymers, one of which is through the addition of lithium salts in the form of LiOH compounds and crosslinking agents in the form of succinic acid to improve the ionic conductivity/conduction and mechanical properties of chitosanbased membranes. The method used in the formation of solid electrolyte polymers is solution casting. The characterization of the isolated chitosan in this study includes characterization of functional groups with FTIR, analysis of the degree of deacetylation, and determination of molecular weight with a viscometer. The isolated chitosan is used as a base material for the formation of electrolyte polymer membranes. The chitosan/LiOH-based electrolyte polymer membrane/succinic acid crosslinker was successfully synthesized by dissolving the chitosan/LiOH/succinic acid mixture with 2% (v/v) acetic acid solvent through stirring for 28 hours at room temperature, then drying at room temperature for 24 hours, and continued oven drying at 35? for 13.5 hours. Furthermore, chitosan based electrolyte polymer membranes and their composites were determined under optimum conditions through functional group characterization with FTIR, swelling degree, mechanical properties test, and ionic conductivity/conduction test. The chitosan-based polymer electrolyte membranes and their composites with optimum conditions were further characterized through XRD diffraction pattern analysis surface morphology and cross-section with SEM, and thermal stability test with TG/DTA. The results showed that the successfully isolated chitosan amounted to 17.84 grams with a deacetylation degree of 76.86% and a molecular weight of 10.86×10-5 grams/mol. Membranes with optimum conditions gave tensile strength and strain values of 31.23 MPa and 68.5% and ionic conductivity/conduction of 2.95×10-5 S/cm obtained from membranes with a composition of 78% (m/m) chitosan, 4% (m/m) succinic acid and 18% (m/m) LiOH. The chitosan/LiOH/succinic acid membrane provides a degree of crystallinity of 59.67% with a rough and hollow surface morphology,and has a thermal resistance of up to 356?. From these results it can be concluded that the chitosan/LiOH membrane / succinic acid crosslinker has the potential to be used as a solid electrolyte in lithium-ion battery applications.