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Zinc oxide (ZnO) is one of the most promising materials applied in Li-ion batteries. In this research, ZnO was synthesized by the thermal decomposition of zinc oxalate dihydrate. This precursor was obtained from the precipitation process of zinc sulfate with oxalic acid. In-depth studies were carried out on the effect of various heating temperatures of zinc oxalate dihydrate precursors on ZnO synthesis. The as-prepared materials were characterized by XRD, SEM, and FTIR. Based on the XRD analysis, the presence of the ZnO-wurtzite phase can be confirmed in samples heated at temperatures above 400 °C. Meanwhile, SEM-EDX results showed that the ZnO particles have a micron size. Cells with ZnO samples as anodes have low columbic efficiency. In contrast, cells with ZnO/Graphite composite anodes have a relatively large capacity compared to pure graphite anodes. Overall, based on the consideration of the characterization results and electrochemical performance, the optimal sintering temperature to obtain ZnO is 600 °C with a cell discharge capacity of ZnO anode and in the form of graphite composites is 356 mAh/g and 450 mAh/g, respectively. This suggests that ZnO can be used as an anode material and an additive component to improve commercial graphite anodes’ electrochemical performance.

Li-ion secondary battery is highly recommended as a power source to highly advanced battery electric vehicles. Among various types, the lithium nickel cobalt aluminum oxide (NCA) battery is considered suitable for high energy and power application. In this study, the NCA cathode material LiNi0.89Co0.08Al0.03O2 was produced via the oxalate co-precipitation technique to reduce the overall production cost and process complexity. Oxalic acid and a small amount of sodium hydroxide were used as the precipitant and pH regulator, respectively. Homogenous and loose metal oxalate precipitate formation was confirmed by X-ray diffraction (XRD), scanning electron microscopy, and Fourier-transform infrared spectroscopy analysis. XRD patterns of the as-obtained micron-sized NCA showed a well-layered hexagonal structure. The electrochemical properties of the cathode in the full cell were thoroughly examined. The specific discharge capacity of the as-obtained NCA in NCA/LiPF6/graphite at a current rate of 20 mA/g was 142 mAh/g. The as-prepared NCA sample had capacity retention of 80% after being charged and discharged at 0.1 A/g for 101 cycles. Scaling up of NCA production process to 2 kg per batch was conducted and evaluation of NCA product quality was performed by material characterization. Based on the overall results and considering the overall process, such an approach is expected to be developed and improved for future large-scale production purposes.

LiFePO4/C cathode material is largely used in Li-ion batteries due to its low toxicity, nonhazardous and high stability features. A facile and simple approach is proposed in LiFePO4/C production using low-cost materials. The effect of carbon addition during the formation of LiFePO4/C was investigated. Based on the XRD and FTIR analyses, olivine-structured LiFePO4/C cathode material was successfully obtained via methanol-based rheological method. The SEM result showed that the material has micron-sized polyhedral shape. The electrochemical performance tests were conducted in an 18,650-type cylindrical battery. The charge–discharge performances were tested at a voltage range of 2.2–3.65 V using charge and discharge rate of 1C. Based on the charge–discharge test, LiFePO4 with 30% carbon addition has the highest specific capacity of 121 mA h/g with excellent cycle and rate performance as a result of successful carbon compositing in LiFePO4 material. This approach is promising to be adapted for mass production of LiFePO4/C.

LiCoO₂ cathode material has been continuously applied in commercial LIBs cells. It has high gravimetric and volumetric density. In this research, an economical approach to obtain LiCoO₂ is proposed. Pure cobalt oxide (Co₃O₄) precursor was obtained via atmospheric precipitation of cobalt sulfate and thermal decomposition of the as-obtained hydroxide precursor. The next heat treatment was performed to obtain LiCoO₂ powder. To investigate the characteristic of the precursor and the final product, XRD, FTIR, and SEM analysis were conducted. The final product has hexagonal structure and quasi spherical morphology. The size of the particle is in micron. The charge-discharge analysis of LiCoO₂ was conducted in LiCoO₂/Graphite system where the initial capacity of LiCoO₂ is 120 mAh/g at the current density of 0.1 C (20 mA/g). Overall, this method can be used for large scale LiCoO­₂ cell production.

LiFePO4 is considered the most environmentally friendly, inexpensive, abundant, has good cycle stability and thermal stability. However, LiFePO4 has the main disadvantage of potential voltage and conductivity which is relatively lower than other batteries. This can be overcome by adding carbon and reducing particle size. The method used in this research is the rheological phase method. This method was chosen because the material used is easy to obtain and the price is cheap, no requires a lot of tools, and good homogeneity. LiFePO4 is very sensitive to direct air. So in this study an evaluation of the effect of argon gas, hydrogen, and nitrogen on the material. LiFePO4 analyzed its morphology with SEM (Scanning Electron Microscopy), its crystallinity with XRD (X-Ray Diffraction) and functional group of LiFePO4 with FTIR (Furier Transformation Infra-Red). Based on the characterization result, the optimum synthesis product continued battery performance test. LiFePO4 H2-Ar produces the best battery capacity compared to other gases because it uses reducing gas which can increase the carbon content of the material.

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Li ion battery or LIB is an energy storage device that provides and store electrical energy and chemical energy, respectively. LIBs have been widely developed in the energy sector owing to their considerable high energy density, high capacity, and long-life cycle. In this study, the LiFePO4/C cathode was synthesized from various precursors FeC2O4, FePO4, Fe3(PO4)2, Fe2O3 obtained via co-precipitation method, and continued with solid-state. The effects of precursors were studied in this study. The precursor and the resulting product were analyzed using XRD, FTIR, SEM, and EDX, while the electrochemical performance was tested using charge-discharge, cycle stability and rate capability. All precursors were successfully synthesized as evidenced by XRD, FTIR, SEM, and EDX characterization tests. Based on electrochemical performance test, the highest capacity that can be achieved is 109 mAh/g obtained from LFP with FeC2O4 precursor, with a reduction in capacity of 54.7% after 50 cycles.