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Since 2004, graphene has risen in popularity owing to its superior properties. However, limits to the scale of production methods have rendered graphene a costly material. Moreover, existing production methods require chemicals that are detrimental to the environment. This study uses Coconut Coir Dust (CCD) as a carbon precursor and an intermediate product in the manufacturing of graphene. Firstly, CCD sieved into a 100 mesh was carbonized using a hydrothermal method at temperatures of 235 o C, 250 o C, and 265 o C, for 4 hours. Following this, the resulting solid residue was pyrolyzed at 1000 o C for 2 hours under the protection of nitrogen (N2). The hydrothermal solid residue was labelled CHT (hydrothermal temperature) and the pyrolysis product was named as SP (hydrothermal temperature). Both samples were characterized using SEM, XRD and EDS. In addition, Raman characterization was conducted for SP samples. At the end of the process (SP), the XRD pattern showed two broad peaks centered around 2θ ~24 o and 44 o corresponding to a (002) and (100) graphite plane. This pattern is similar to that of reduced-graphene oxide. SEM images showed a sheet-like microstructure is caused by undegraded lignin. A perforated and corrugated sheet formed after pyrolysis, which subsequently confirms the formation of reduced-graphene oxide. Furthermore, the Raman result indicates that higher hydrothermal temperatures lead to an increasing integrated ID/IG ratio. The ratios were 1.62, 1.71 and 1.77, for SP 235, SP 250, and SP 265, respectively. Research results conclude that the carbonaceous material formed through hydrothermal and pyrolytic processes contained a mixture of an amorphous-carbon form and a graphene-like cluster. Results additionally show a similar structure with reduced-graphene oxide.

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Cylindrical cell Lithium ion battery with a pouch casing has been made at the Integrated Battery Laboratory, BATAN. LiFePO4 double sided coated aluminum foil with a thickness of 180 μm is used as a cathode sheet. The anode sheet is made from two-sided artificial graphite coated on copper foil with a thickness of 197 μm. The composition, crystal structure, of the coated LiFePO4 was measured by XRD. Battery cells are built by rolling thin layers of cathode, separator, and anode material into cylindrical shape using a rolling machine. The cylindrical cell is inserted into an aluminum bag and then sealed at 175°C. Cylindrical cell-bag inserted into the Glove Box then filled with ∼ 2.5 ml of LiPF6 electrolyte liquid. A vacuum sealing machine is used to seal the remainder of the bag set at 175 oC. The performance of lithium ion batteries is characterized by using a battery analyzer. LiFePO4 shows a release capacity of 250.00 mAh, with a specific capacity of 124.10 mAh/g in the 1st cycle and 100.20 mAh/g after 100th cycle, at a rate of 0.3C. The cell shows good performance after 100 cycles with 80.74% retention.

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Lithium ion battery technology is an alternative energy supply for portable equipment, electronics devices and high power applications such as electric vehicle and power storage for renewable energy. Electrolyte of lithium ion battery plays an important role in determining battery performance. It consists of lithium salt, commonly use lithium hexafluorophosphate (LiPF6), dissolved in organic carbonate solvent and additives. However, LiPF6 is thermally unstable and influence battery performance significantly. Moreover, the standard solvent also has some disadvantages on the electrical vehicle application. Because of this drawback, the selection of another lithium salt, lithium bis (trifluoromethylsulfonyl) imide (LiTFSI) combined with ionic liquid BMIMTFSI become a great importance. Therefore, in this study, ionic conductivity characteristics of liquid electrolyte based on LiTFSI was investigated. The ionic conductivity measurement of lithium bis (trifluoromethylsulfonyl) imide (LiTFSI) electrolyte in carbonate solvents with and without ionic liquid BMIMTFSI as an additive have been investigated. The ionic conductivity of LiTFSI with ionic liquid is larger than LiTFSI without ionic liquid as an additive, namely 3.1 mS/cm and 2.7 mS/cm.