Bambang Prihandoko

Electrochemical performance of LiV3O8 micro-rod at various calcination temperatures as cathode materials for lithium ion batteries

Lithium vanadium oxide (LiV3O8) has been successfully synthesized by hydrothermal method followed by calcination via the reaction of Lithium hydroxide (LiOH) and ammonium metavanade (NH4VO3). The precursors were heated at hydrothermal at 200 °C and then calcined at different calcination temperature in 400, 450, and 500 °C. The characterization by X-ray diffraction (XRD) and scanning electron microscope (SEM) is indicated that LiV3O8 micro-rod have been obtained by this method. The cyclic voltammetry (CV) result showed that redox reaction occur in potential range between 2.42 - 3.57 V for the reduction reaction and oxidation reaction in potential range between 2.01 V-3.69 V. The highest result was obtained for sample 450 °C with specific discharge capacity of 138 mA/g. The result showed that LiV3O8 has a promising candidate as a cathode material for lithium ion batteries.Lithium vanadium oxide (LiV3O8) has been successfully synthesized by hydrothermal method followed by calcination via the reaction of Lithium hydroxide (LiOH) and ammonium metavanade (NH4VO3). The precursors were heated at hydrothermal at 200 °C and then calcined at different calcination temperature in 400, 450, and 500 °C. The characterization by X-ray diffraction (XRD) and scanning electron microscope (SEM) is indicated that LiV3O8 micro-rod have been obtained by this method. The cyclic voltammetry (CV) result showed that redox reaction occur in potential range between 2.42 - 3.57 V for the reduction reaction and oxidation reaction in potential range between 2.01 V-3.69 V. The highest result was obtained for sample 450 °C with specific discharge capacity of 138 mA/g. The result showed that LiV3O8 has a promising candidate as a cathode material for lithium ion batteries.

The effect of Li2CO3 substitution on synthesis of LiBOB compounds as salt of electrolyte battery lithium ion

Development of the synthesis of LiB(C2O4)2 compounds continues to evolve along with the need for electrolyte salts to support the research of the manufacture of lithium ion batteries. A study had been conducted on the effect of Li2CO3 substitution on the synthesis of LiB(C2O4)2 or LiBOB compounds. LiBOB was a major candidate to replace LiPF6 as a highly toxic lithium battery electrolyte and harmful to human health. Synthesis of Lithium bis(oxalato) borate used powder metallurgy method. The raw materials used are H2C2O4.2H2O, Li2CO3 or LiOH and H2BO3 from Merck Germany products. The materials are mixed with 2: 1: 1 mol ratio until homogeneous. The synthesis of LiBOB refers to previous research, where the heating process was done gradually. The first stage heating is carried out at 120°C for 4 hours, then the next stage heating is carried out at 240°C for 7 hours. The sample variation in this study was to distinguish the lithium source from Li2CO3 and LiOH. Characterization was done by XRD to know the phase formed, FTIR to confirm that functional group of LiB(C2O4)2 compound, SEM to know the morphological structure, and TG/DTA to know the thermal properties. The results of the analysis shows that LiBOB synthesis using Lithium source from Li2CO3 has succeeded to form LiBOB compound with more LiBOB phase composition is 59.1% and 40.9% LiBOB hydrate phase, SEM morphology shows powder consist of elongated round particle porous and similar to LiBOB commercial and show higher thermal stability.Development of the synthesis of LiB(C2O4)2 compounds continues to evolve along with the need for electrolyte salts to support the research of the manufacture of lithium ion batteries. A study had been conducted on the effect of Li2CO3 substitution on the synthesis of LiB(C2O4)2 or LiBOB compounds. LiBOB was a major candidate to replace LiPF6 as a highly toxic lithium battery electrolyte and harmful to human health. Synthesis of Lithium bis(oxalato) borate used powder metallurgy method. The raw materials used are H2C2O4.2H2O, Li2CO3 or LiOH and H2BO3 from Merck Germany products. The materials are mixed with 2: 1: 1 mol ratio until homogeneous. The synthesis of LiBOB refers to previous research, where the heating process was done gradually. The first stage heating is carried out at 120°C for 4 hours, then the next stage heating is carried out at 240°C for 7 hours. The sample variation in this study was to distinguish the lithium source from Li2CO3 and LiOH. Characterization was done by XRD to know the phase...

STUDI SIFAT ELEKTROKIMIA SEL BATERAI SEKUNDER POUCHCELL LITHIUM ION LIFEPO4/GRAPHITE APLIKASI DAYA TINGGI

In this work, have been fabricated cathode electrode from LiFePO4 powder and anode from commercial Graphite powder. Full cell batteries fabricated in Pouchcell shaped test samples. Lithium ion cell configuration are LiFePO4 // LiPF6 // graphite, 1 M LiPF6 in EC/DEC is used as the liquid electrolyte. Cell batteries Perfomance characterized by some tests conducted on the cyclic voltrametry, charge-discharge and EIS (electrochemical impedance spectroscopy. The result value are the capacity reached approximately 80 mAh / g, with the voltage Voc perfectly stable at 3.28 V. The discharged capacity can be taken up to 5C almost over 40% , with after 50 cycles for life cycle test the capacity loss is retain still 95% at 0.33C.

Variation of Carbon Coating on Li2Na2Ti6O14 as Anode Material of Lithium Battery

Li2Na2Ti6O14 was developed from Li5Ti4O12 as a good active material for anode of the lithium battery. Li2Na2Ti6O14 was prepared by a preliminary formation of Li2Na2Ti6O14 through solid state reaction with calcination temperature at 700 °C, and sintering temperature at 800 oC for 8 hours. By analysis of XRD patterns, Li2Na2Ti6O14 shows spinel structure which similar as Li5Ti4O12. Carbon coating on Li2Na2Ti6O14 was done by using pyrolysis method at a temperature of 700 oC for 2 hours. The process of carbon coating was done under variation of comparison between Li2Na2Ti6O14 and tapioca powder as a carbon source, i.e. 8:1, 10:1 and 12:1. The working voltage of Li2Na2Ti6O14/C product was 1,2 volt. The other analysis were conductivity, cyclic voltammeter, and charge – discharge.

The effect of 0.025 Al-doped in Li4Ti5O12 material on the performance of half cell lithium ion battery

The effect of 0.025 Al-doped Li4Ti5O12 as anode material for Lithium Ion battery had been studied. The pure and 0.025 Al-doped Li4Ti5O12 were synthesized through solid state process in air atmosphere. Physical characteristics of all samples were observed by XRD, FTIR, and PSA. The XRD analysis revealed that the obtained particle was highly crystalline and had a face-centered cubic spinel structure. The XRD pattern also showed that the 0.025 Al-doped on the Li4Ti5O12 did not change crystal structure of Li4Ti5O12. FTIR analysis confirmed that the spinel structure in fingerprint region was unchanged when the structure was doped by 0.025 Al. However the doping of 0.025 Al increased particle size significantly. The electrochemical performance was studied by using cyclic voltammetry (CV) and charge-discharge (CD) curves. Electrochemical analysis showed that pure Li4Ti5O12 has higher capacity than 0.025 Al-doped Li4Ti5O12 had. But 0.025 Al-doped Li4Ti5O12 possesses a better cycling stability than pure Li4Ti5O12.

The Effect of Addition of Multi Wall Carbon Nano Tubes (MWCNT) Reinforcement to the Characteristics of Carbon Composite Bipolar Plate

Polymer electrolyte membrane fuel cell (PEFMC) or also known as proton exchange membrane fuel cell is a chemical conversion device that converts hydrogen and oxygen into electrical energy, heat, and water. One of the most important components of PEMFC is bipolar plate, in which it allows for electrons to flow from the anode to the cathode. The objective of this study was to analyze the effect of the addition of multi walled carbon nanotubes (MWCNT) to increase the mechanical and electrical properties of bipolar plate carbon polymer composite. We utilized graphite waste product from electric arc smelting as reinforcementand carbon black made from coconut husk by pyrolysis process as a filler. Bipolar plates were made by compression moulding method at a pressure of 55 MPa and a temperature of 100 o C for 4 hours. Characterization in this study includes density testing, porosity testing, flexural testing, electrical conductivity testing, and observation of the flexural fracture morphology using FESEM. Based on this study, it showed that the addition of 5 %wt MWCNT yielded optimal properties of the bipolar plate (the density was 1.51 g/cm3, the value of porosity was 1.94 %, the flexural strength was 63.31 MPa, and the electrical conductivity was 2.30 S/cm). In conclusion, adding MWCNT as reinforcement in PEMC bipolar plates could reduce the density and the porosity. Thus, it could improve the electrical conductivity and flexural strength of the bipolar plate carbon polymer composites.

Electrochemical Behavior of Li4Ti5O12 under In Situ Process of Sintering and Surface Coating with Cassava Powder

Anode active material Li4Ti5O12/C has an advantage to increase the life time and the ability to charge and discharge lithium batteries. An experiment was carried out to make Li4Ti5O12/C more cheaper and simple process. Preparation of Li4Ti5O12/C was carried out with stoichiometric composition of raw materials TiO2 (Merck) and LiOH.H2O (Germany) under powder metallurgy method. After mixing and calcinations cassava starch as a source of carbon black coating could be mixed under comparison 1:1 with calcinations powders. Pyrolisis process was done in - situ by the sintering process at temperature variation, i.e. 800, 850 and 900°C for 1 hour. XRD test results indicated the presence of anatase TiO2 entire sample. The best results of powder Li4Ti5O12/C with in situ process under 850°C for 1 hour had conductivity in the order of 10-4S/cm and capacity round 5mAh/g. Carbon coating of cassava starch that is well identify in the black color of sample powder and EDX analysis, gave influence on electrochemical graphics of oxidation and reduction by cyclic voltammeter. The working voltage of Li4Ti5O12/C is in general 1.55V.

The Effects of Carbon Black Loading on the Characteristics of Carbon Composite Bipolar Plate by Utilizing Graphite Waste Products

Current energy resources derived from fossil fuels thinning, and the issue global warning make the relevant parties that concern about the environment has been trying to find alternative renewable energy. Among the renewable energy options, the fuel cell is one of the many alternatives studied by the researchers in the world. One type of fuel cell that is currently being investigated is the proton exchange membrane fuel cell cel. The utilization of graphite and carbon black waste product is expected to result in light-weight and cost-effective bipolar plates.by using recycle materials. In this paper, we used graphite EAF as reinforcement together with carbon black that comes from the coconut husk pyrolysis process and epoxy resin as a binder. We examined the effects of carbon black loading at 5 %wt and 10 %wt, which influenced by differential pressure applied on compression molding process on density, porosity, flexural strength and electrical conductivity of the resulting polymer carbon composite bipolar plate. Pressure was applied from 30 MPa - 60 MPa in increments of 5 MPa while maintaining constant temperature operation at 70oC for 4 hours. Maximum value of bipolar plate was achieved by 5 %wt CB at application 55 MPa, density of 1.69 g/cm3, the flexural strength was measured to be 48 MPa with the porosity of 0.7%, and electrical conductivity of 1.03 S/cm.We demonstrated that waste product such as graphite EAF and carbon black are a good candidate for manufacturing of polymer carbon composite bipolar plates.

The Effects of Compression Pressure Applied on the Manufacture of Carbon Composite Bipolar Plate for PEMFC by Utilizing Graphite Waste Products

Proton electrolyte membrane fuel cells (PEMFC) have near zero carbon dioxide and hazardous pollutant emission. Thus, it is considered as one of energy sources for transportation and other application which can improve environmental performance by decreasing the emission of greenhouse gases and other air pollutant. In accordance with its environmental preservation values, graphite waste product from electric arc furnace (graphite EAF) was chosen as a potential candidate material for bipolar plate for PEMFC. The utilization of graphite waste product is expected to result in light-weight and cost-effective bipolar plates. In this paper, we used graphite EAF as a filler together with carbon black and epoxy resin as a binder. We examined the effects of differential pressure applied on compression molding process on density, porosity, flexural strength and electrical conductivity of the resulting carbon polymer composite bipolar plate. Pressure was applied from 30 MPa - 60 MPa in increments of 5 MPa while maintaining constant temperature operation at 700C for 4 hours. Maximum value of bipolar plate density was achieved at application 55 MPa, of 1.69 g/cm3. At this condition, the flexural strength was measured to be 48 MPa with the porosity of 0.7%, and electrical conductivity of 1.03 S/cm. Taken together, we demonstrated that graphite EAF is a good candidate for the manufacturing of polymer composite bipolar plates.