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Corncobs are a waste product from corn farming that are abundant in Indonesia. Corncobs have a high cellulose content, more than 40%, which made it useful for synthesizing CMC. CMC is a cellulose derivative that is widely used in many industries such as food, pharmaceutical, detergent, textile, cosmetic product and binder. In this paper, we use CMC that are synthesized from corncobs as binder in the electrodes of lithium ion battery. The steps of synthesizing CMC from corncobs started with the isolation of the cellulose, then followed by the processes of alkalization, carboxymethylation and finally the purification. FTIR spectrum shows that CMC are successfully synthesized. The presence of strong absorption band at 1613 cm-1 is related to the stretching vibration of the carboxyl group (COO-). The absorption in the 1300–1450 cm-1 region is due to symmetrical deformations of CH2 groups. While the broad absorption around 3427 cm-1 is due to the stretching of the hydroxyl groups (-OH). Test on three samples of different sizes, (mesh-100, mesh-60 and mesh-40) gives CMC purity values of 98.69%, 98.56% and 97.77%, respectively. In the application of CMC as anode binder, the best composition is 4% CMC, where it gives the highest conductivity of 0.587 S/cm. Voltammogram measurement with a scan rate of 50 mV/s in the voltage range of -1 to 1 Volt gives the capacitance value of 2237 μF.

Muon spin relaxation experiment has been conducted to probe the hopping mechanism in the poly(3-hexylthiophene-2,5-diyl) (P3HT) for both types of regio-random (Rdm) and regio-regular (RR). In this study we have performed calculations over the collected data to obtain the parallel and perpendicular diffusion rates, at temperatures of 10 K and 300 K. The calculation is based on the fitting method to the empirical function that relates the relaxation rate with the diffusion rates. For Rdm-P3HT, we have obtained the parallel diffusion rate to be 5.43 x 1013 rad/s at 300 K and 4.90 x 1014 rad/s at 10 K. While the perpendicular diffusion rates are 5.29 x 108 rad/s at 300 K and 1.88 x 106 rad/s at 10 K. For RR-P3HT, we have obtained the parallel diffusion rate to be 1.04 x 1014 rad/s at 300 K and 1.28 x 1015 rad/s at 10 K. While the perpendicular diffusion rates are 6.10 x 108 rad/s at 300 K and 5.35 x 105 at 10 K. The diffusion rates of RR-P3HT are higher than that of Rdm-P3HT, especially in the parallel direction. In both types of material, the parallel diffusion rate decreased with temperature, while the perpendicular diffusion rate increased with temperature, showing a change of behavior from 1D to 3D direction of charge transport.

The hopping mechanism in the regio-random poly (3-hexylthiophene-2,5-diyl) was investigated through study on the diffusion rate of the charge carrier transport from the data of Longitudinal Field (LF) muon-spin-relaxation measurements. Values of the parallel and perpendicular diffusion rate were calculated following the methods applied in NMR. It is found that diffusion rate along the polymer chain slowly decreases from low to high temperatures, while diffusion rate perpendicular to the polymer chain rises significantly from low to high temperatures.