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"Senyawa Li4Ti5O12 merupakan senyawa yang memiliki potensial sebagai material anoda namun memiliki beberapa kekurangan. Kekurangan dari LTO adalah memiliki konduktivias yang rendah dan kapasitas teoritis yang lebih rendah dari grafit yang dipakai sebagai material anoda pada baterai lithium ion. Pada penelitian ini mixing element yang diberikan pada LTO adakah karbon aktif dan SnO2 untuk menutupi kekurangan dari LTO. Jumlah karbon aktif yang diberikan adalah sebanyak 1, 3 dan 5. Persen SnO2 yang ditambahkan adalah 10. Senyawa SnO2 ditambahkan pada komposit LTO/C menggunakan metode deposisi in-situ. Dengan metode deposisi in-situ senyawa SnO2 yang diperoleh memiliki ukuran partikel yang kecil dan tersebar secara merata. Li4Ti5O12 disintesis menggunakan metode sol-gel, hidrothermal dan mekanokimia dengan menggunakan LiOH sebagai sumber ion lithium. Karakterisasi yang digunakan adalah XRD dan SEM-EDX. Untuk pengujian performa baterai dilakukan pengujian EIS, CV dan CD untuk mengetahui efek dari penambahan karbon aktif dan SnO2 pada performa elektrokimia. Hasil pengujian XRD menunjukkan partikel SnO2 telah terbentuk dan tanpa pengotor. Hasil pengujian SEM menunjukkan partikel SnO2 yang terbentuk memiliki ukuran partikel yang kecil dan tersebar merata begitu pula dengan partikel karbon aktif tersebar secara merata. hasil pengujian CV menunjukkan bahwa penambahan karbon aktif meningkatkan kapasitas spesifik LTO. Hasil pengujian CD menunjukkan dengan penambahan karbon aktif, capacity loss pada c-rate tinggi dapat dikurangi.

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Li4Ti5O12 is one of the compound which has potential as anode material on lithium ion battery but with certain limitation. The limitation of Li4Ti5O12 are it hasa low conductivity and low theoritical capacity compared to graphite which is anode material of state of the art litihum ion battery.

In this research mixing element given to LTO are activated carbon and SnO2 to decrease LTO limitation. Activated carbon as mixing element added in LTO are 1, 3 and 5. SnO2 added to LTO are 10. SnO2 added to LTO composite with in situ deposition method.

Using in situ deposition method, SnO2 particle acquired from deposition has small particle size and distribute evenly. Li4Ti5O12 synthetized with sol gel method, hydrotermal method and mechano chemical method using LiOH as ionic Li source. The sample was characterized with XRD and SEM EDX. For battery performance, EIS, CV and CD testing was conducted to determine the effect of addition activated carbon and SnO2 on electrochemical performance.

Based on XRD result, SnO2 particle is formed with no residue from previous reaction. Based on SEM EDS result, SnO2 particle has small size and distribute evenly same with active carbon. The result from CV testing show with addition of activated carbon increase specific capacity of LTO. The result from CD tewting show with addition of activated carbon, capacity loss on high c rate can be reduced."

"Omar Abu Mohareb proposes a novel dynamic inductor control (DIC) that can be generally applied to various DC-DC converter types. The aim is to improve the converter efficiency throughout controlling the inductance value at all operating points without consequential complexity or increase in the inductor cost and size. The dynamic inductor control implies the maximum energy transfer (MET) concept to improve the DC-DC converter efficiency and preserve a fast system dynamics against load changes at the same time.ContentsEffects of Varying Inductance Value on Converter Efficiency and PerformanceBoost Battery Charger ModelingDevelopment of Dynamic Inductor Control (DIC) and Maximum Energy Transfer (MET) ConceptsDynamic Inductor Control Concept Simulation and Implementation"

"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)."

"Tahapan proses yang dilakukan untuk pengambilan kembali logam lithium adalah leaching, pembuatan membran emulsi, dan ekstraksi. Limbah baterai Li-Ion dikarakterisasi terlebih dahulu dengan XRD. Hasil XRD menunjukan bahwa terdapat kandungan logam lithium di limbah dalam bentuk LiCoO2. Kondisi optimum untuk proses leaching adalah menggunakan asam sitrat 1,5 M, rasio padatan/cairan: 20 gram/L, dan kecepatan pengadukan 400 rpm pada suhu 550C selama 50 menit dengan hasil 99,3% lithium berhasil ter-leaching. Lalu untuk kondisi optimum proses pembuatan membran emulsi adalah menggunakan 0,03 M Cyanex 921, 8% w/v SPAN 80, 0,05 M H2SO4, rasio volume fasa ekstraktan/fasa internal: 1/1, dan kecepatan pengadukan 1150 rpm selama 60 menit yang mampu menghasilkan membran emulsi dengan tingkat kestabilan diatas 90% setelah 4 jam. Selanjutnya pada proses ekstraksi dengan kondisi optimum pH 6 untuk fasa umpan, rasio volume fasa emulsi/fasa umpan: 1/2, dan kecepatan pengadukan 175 rpm selama 15 menit dengan hasil 63,4% lithium berhasil ter-ekstrak.

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The process to acquire lithium metal are leaching, creation of emulsion membrane, and extraction. The spent Li-Ion battery was characterized first by XRD. Result of XRD showed that there is lithium in spent battery in the form of LiCoO2. The optimum condition for leaching process is using citric acid 1,5 M, solid/liquid ratio: 20 gram/L, and stirring speed 400 rpm in 550C for 50 minutes with result 99,3% lithium successfully leached. Then the optimum condition to make emulsion membrane is using 0,03 M Cyanex 921, 8% w/v SPAN 80, 0,05 M H2SO4, extractant phase/internal phase volume ratio: 1/1, and stirring speed 1150 rpm for 60 minutes able to produce emulsion membrane with stability level of above 90% after 4 hours. Next in extraction process with optimum condition pH 6 for external phase, emulsion phase/external phase volume ratio: 1/2, and stirring speed 175 rpm for 15 minutes with result 63,4% lithium successfully extracted."