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"Litium titanat merupakan salah satu senyawa yang digunakan sebagai anoda pada baterai litium ion. Senyawa ini disintesis dengan menggunakan metode solid state dengan mencampurkan xerogel TiO2 yang dihasilkan dari metode sol-gel dengan rasio hidrolisis Rw 2,00, dan litium karbonat (Li2CO3) sebagai sumber lithium dan dilakukan sintering pada suhu 650°C. Pada penelitian ini, xerogel TiO2 dicampurkan dengan empat variasi komposisi litium yaitu stoikiometris, excess 5%, excess 10%, dan excess 15% pada High-Energy Ball Miller (HEBM) selama 1 jam. Pengaruh dari masing-masing komposisi diamati dengan X-ray diffraction (XRD), Brunauer-Emmet-Teller (BET), Simultaneous Thermal Analysis (STA) dan Scanning Electron Microscope (SEM).Hasil penelitian menunjukkan bahwa pada komposisi litium stoikiometris dihasilkan senyawa Li4Ti5O12 dengan ukuran kristalit 19,19 nm, luas permukaan 11,47 m2/g, struktur morfologi tidak beraturan (aglomerasi). Pada komposisi litium excess 5% dihasilkan Li4Ti5O12 dengan ukuran kristalit 41,55 nm, luas permukaan 58,80 m2/g, dan sturktur morfologi tidak beraturan (aglomerasi). Pada komposisi litium excess 10% dihasilkan senyawa Li4Ti5O12 dengan ukuran kristalit 43,12 nm, luas permukaan 72,06 m2/g, dan struktur morfologi tidak beraturan (aglomerasi). Sedangkan, pada komposisi litium excess 15% dihasilkan senyawa Li4Ti5O12 dengan ukuran kristalit 50,31 nm, luas permukaan 9,06 m2/g, dan struktur morfologi tidak beraturan (aglomerasi).

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Lithium titanate (Li4Ti5O12)/LTO is one of the compounds used as anodes in lithium ion batteries. This compound is synthesized using solid state method by mixing TiO2 anatase prepared by sol-gel method with hydrolisis ratio Rw 2,00 calcined at 300oC for 2 h and lithium carbonate (Li2CO3) as a source of lithium and then sintering is performed at 650oC. The TiO2 anatase are mixed with stoichiometric, 5% excess, 10% excess, and 15% excess lithium compositions in High-Energy Ball Miller (HEBM) for 1 h. The compounds obtained are observed using X-ray diffraction (XRD), Brunauer-Emmet-Teller (BET), Simultaneous Thermal Analysis (STA) and Scanning Electron Microscope (SEM).

The results showed the compounds of Li2TiO3, TiO2 rutile, and small amount of Li4Ti5O12 with irregular morphological structures (agglomeration). The stoichiometric lithium compositions produces average crystallite sizes 19,19 nm and surface area 11,47 m2/g. Then, the 5% excess lithium compositions produces average crystallite sizes 41,55 nm and surface area 58,80 m2/g. Further, the 10% excess lithium compositions produces average crystallite sizes 43,12 nm and surface area 72,06 m2/g. Finally, the 15% excess lithium compositions produces average crystallite sizes 50,31 nm and surface area 9,06 m2/g."

"Lithium Titanate (Li4Ti5O12) or (LTO) has a potential as an anode material for a high performance lithium ion battery. In this work, LTO was synthesized by a hydrothermal method using Titanium Dioxide (TiO2) xerogel prepared by a sol-gel method and Lithium Hydroxide (LiOH). The sol-gel process was used to synthesize TiO2 xerogel from a titanium tetra-n-butoxide/Ti(OC4H9)4 precursor. An anatase polymorph was obtained by calcining the TiO2 xerogel at a low temperature, i.e.: 300oC and then the hydrothermal reaction was undertaken with 5M LiOH aqueous solution in a hydrothermal process at 135oC for 15 hours to form Li4Ti5O12. The sintering process was conducted at a temperature range varying from 550oC, 650oC, and 750oC, respectively to determine the optimum characteristics of Li4Ti5O12. The characterization was based on Scanning Thermal Analysis (STA), X-ray Powder Diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), Fourier Transform Infrared spectroscopy (FTIR), and Brunauer-Emmett-Teller (BET) testing results. The highest intensity of XRD peaks and FTIR spectra of the LTO were found at the highest sintering temperature (750oC). As a trade-off, however, the obtained LTO/Li4Ti5O12 possesses the smallest BET surface area (< 0.001 m2/g) with the highest crystallite size (56.45 nm)."

"Litium titanat (Li4Ti5O12) merupakan senyawa yang digunakan sebagai anoda baterai ion litium. Senyawa litium titanat disintesis berdasarkan metode solid state dengan mereaksikan TiO2 xerogel yang dibuat dengan metode sol-gel dan litium oksida (Li2O). Dalam penelitian ini menggunakan tiga variasi penambahan kadar massa litium oksida (Li2O); massa Li2O sesuai stokiometri (0% melebihi stokiometri), 50% massa Li2O melebihi stokiometri dan 100% melebihi nilai stokiometri. Pengaruh dari penambahan kadar massa litium oksida (Li2O) pada struktur, morfologi, dan energi celah pita tersebut diamati. Sampel yang terbentuk diuji dengan menggunakan X-Ray diffraction, scanning electron microscope (SEM) dan UV-Vis spectroscopy. Hasil penelitian menunjukan bahwa dengan penambahan massa Li2O sesuai stokiometri membentuk senyawa Li4Ti5O12 dan pengotor seperti TiO2 rutile dan Li2TiO3 dengan ukuran kristalit 13,7 nm, ukuran diameter partikel 0,540 μm band gap energy 3,864 eV, penambahan massa Li2O 50% melebihi stokiometri membentuk senyawa Li2TiO3 dengan ukuran kristalit 7,2 nm, ukuran diameter partikel 1,062 μm dan band gap energy 3,838 eV dan penambahan 100% massa Li2O melebihi stokiometri membentuk Li2TiO3 dengan ukuran kristalit 12,4 nm, ukuran diameter partikel 1,916 μm dan band gap energy 3,778 eV. Senyawa Li4Ti5O12 terbentuk hanya dengan penambahan Li2O sesuai stokiometri. Untuk mensintesis senyawa Li4Ti5O12 bebas dari pengotor mengunakan metode solid state dapat mengacu pada diagram fasa Li2O-TiO2 (29% mol Li2O-71% mol TiO2).

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Lithium titanate (Li4Ti5O12) is anode material for application in lithium ion battery. Lithium titanate was synthesized by solid-state method using xerogel TiO2 was prepared by sol–gel process and commercial lithium oxide (Li2O) powder. This research uses 3 various content of lithium oxide (Li2O); 0% Li2O mass excess, 50% Li2O mass excess, and 100% Li2O mass excess. The effect of adding lithium oxide (Li2O) on structure, morphology of particle surface, and band gap energy was examined. Samples were obtained by X-ray diffraction, scanning electron microscope (SEM), ultraviolet visible (UV-Vis).

The results show with adding lithium oxide stoichiometry (0% Li2O excess) produces Li4Ti5O12 and impurities such as rutile TiO2 and Li2TiO3, it produces Li2TiO3 with 50% Li2O excess and it produces Li2TiO3 with 100% Li2O excess. In this research show with appropriate of stochiometry content (0% Li2O excess) produces Li4Ti5O12 with crystallite size is 13,7 nm and impurities namely Li2TiO3 with crystallite size is 22,8 nm and TiO2 with crystallite size 9,14 nm, diameter particle size is 0,540 μm and bandgap energy 3,864 eV. 50% Li2O excess produces Li2TiO3 with crystallite size 7,2 nm, diameter particle size is 1,062 μm and bandgap energy 3,838 eV and with 100% Li2O excess produces Li2TiO3 with crystallite size 12,4 nm, diameter particle size is 1,916 μm and band gap energy is 3,778 eV. The Li4Ti5O12 compound was formed only with appropriate of stoichiometry content. In order to make high purity of Li4Ti5O12 compound on solid state reaction, Li2O-TiO2 phase diagram (29% mol Li2O-71% mol TiO2) can be used as reference."