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Kelvin Muhammad Farros
Abstrak :
Litium yang sekarang menjadi salah satu material paling dicari karena sifatnya yang dapat digunakan sebagai baterai menjadi salah satu faktor untuk dilakukan proses peningkatan kadar dari sumber batuan. Froth flotation merupakan suatu proses yang dilakukan untuk memisahkan mineral yang ingin diambil dengan pengotornya berdasarkan dengan sifat hidrofobik dan hidrofilik dari mineral. Keberhasilan proses froth flotation ditentukan oleh beberapa parameter seperti ukuran partikel, pH, waktu, dan penggunaan zat aditif seperti kolektor dan frother. Berdasarkan studi literatur didapatkan hasil yang maksimal pada ukuran partikel -0,074 mm, kondisi pH basa 8-10, waktu 5 menit, dan menggunakan asam oleat/sodium oleat NaOL)/tributyl tetradecyl phosphonium chloride TTPC. Penggunaan aktivator Fe3+ juga meningkatkan hasil persentase recovery. Parameter-parameter tersebut yang diketahui dapat meningkatkan persentase recovery dikarenakan dapat memaksimalkan kerja kolektor dalam memisahkan mineral.
Lithium is now one of the most sought after materials because of its nature which can be used as a battery to be one of the factors for the process of increasing lithium content from rock source. Froth flotation is a process that is carried out to separate the minerals with the impurities based on the hydrophobic and hydrophilic properties of the mineral. The success of froth flotation process is determined by several parameters such as particle size, pH, time, and the use of additives such as collectors and frother. Based on literature studies, maximum results were obtained at partcle size of -0.074 mm, alkaline pH conditions 8-10, 5 minutes, and using oleic acid/sodium oleic NaOL/tributyl tetradecyl phosphonium chloride TTPC. The use of activator Fe3+ also increases the percentage recovery results. These parameters are known to increase the percentage of recovery because they can maximize the work of collector in separating minerals.
Depok: Fakultas Teknik Universitas Indonesia, 2020
S-pdf
UI - Skripsi Membership  Universitas Indonesia Library
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Teguh Imam Burhanudin
Abstrak :
Mineral sintetis yang terbentuk dari campuran Al,03, LiOH dan SiO, dan dipanggang pada temperatur 1200°C, merupakan bahan yang digunakan pada penelitian ekstraksi lithium ini. Dengan tujuan mengetahui titik optimum waktu proses pelindian dengan menggunakan pelarut KOH di dalam muffle furnace. Selain itu, untuk mengetahui titik optimum laju alir gas CO, dalam proses pengendapan larutan LiOH_ hasil pelindian sampai menjadi endapan LizCO3. Hasil penelitian menunjukkan bahwa terjadi peningkatan produk lithium yang larut membentuk LiOH seiring dengan semakin lamanya waktu pelindian. Dimana waktu optimumnya adalah 90 menit dengan recovery lithium pada proses pelindian sebesar 11.76%. Selain itu, pada proses pengendapan larutan LiOH menjadi endapan LizCO3 mengalami kenaikan recovery lithium seiring dengan kenaikan laju alir gas CO 2. Dimana laju alir optimum adalah 1.5. liter/menit dengan recovery lithium pada proses pengendapan sebesar 63.01%. Sedangkan nilai recovery total proses ekstraksi lithium dari mineral sintetis sampai menjadi endapan LixCO3 adalah sebesar 6.86%. ......Synthetic mineral which formed from the mixture of Al,O3, LiOH and SiO>2 and was roasted at 1200°C, is a material which was used in this lithium extraction research. It is to find optimum time point of the leaching process using KOH solvent in muffle furnace. In addition, to find optimum flow rate point of CO gas in the process of precipitating LiOH solution as the leaching result until it becomes LizCO3 precipitation. The research results show that there is an increase of Li product that dissolved which formed LiOH along with the increase of the length of leaching process. The optimum length is at 90 minutes with recovery lithium. in leaching process as much as 11.76%. In addition, within process of precipitation LiOH solution to be LixCO3 deposition there is an increase of recovery lithium along with the increase of CO» gas flow rate. The optimum flow rate is rate 1.5 litre per minute with recovery lithium at precipitation process value at 63.01%. Whereas the value of the total efficiency of the lithium extracting process from synthetic mineral until it becomes deposition is worth 6.86 %
Depok: Fakultas Teknik Universitas Indonesia, 2013
S47076
UI - Skripsi Membership  Universitas Indonesia Library
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Adam Arthanugraha
Abstrak :
Pada penelitian ini, proses ekstraksi lithium dari mineral sintetis telah dilakukan. Mineral sintetis yang digunakan pada penelitian ini terbentuk dari campuran senyawa LiOH, Al2O3, dan SiO2 yang kemudian dilakukan pemanggangan pada temperatur 12000 C. Proses ekstraksi ini terbagi atas dua tahap, yaitu tahap pelindian dan tahap presipitasi. Tahap pelindian dilakukan dengan menggunakan NaOH sebagai pelarutnya dengan tujuan mendapatkan LiOH. Tahap presipitasi dilakukan dengan menambahkan Na2CO3 dan CO2 ke dalam LiOH dengan tujuan mendapatkan Li2CO3. Hasil penelitian menunjukkan bahwa terjadi peningkatan produk lithium yang larut membentuk LiOH seiring dengan meningkatnya temperatur pelindian. Temperatur pelindian optimum adalah 2400 C dengan pemulihan lithium sebesar 10.39%. Pada tahap presipitasi, pemulihan lithium yang diperoleh akan semakin tinggi seiring dengan peningkatan waktu reaksi dimana waktu reaksi optimum adalah 70 menit dengan pemulihan lithium sebesar 81.13%. Nilai pemulihan total proses ekstraksi lithium dari mineral sintetis hingga menjadi Li2CO3 adalah sebesar 8.43%. ......In this work, the process of lithium extraction from synthetic mineral has been done. Synthetic mineral that used in this work are made from LiOH-Al2O3-SiO2 mixture which then roasted at temperature 12000 C. This extraction process divided into two stage, leaching stage and precipitation stage. Leaching is done by using NaOH as a solvent in order to get LiOH. Precipitation stage is done by adding Na2CO3 and CO2 into LiOH in order to get Li2CO3. The results showed that there has been an increase of lithium product that dissolved and formed LiOH along with the increase of leaching temperature. The optimum leaching temperature is 2400 C with a recovery of 10.39% lithium. At the precipitation stage, recovery of lithium that obtained will be higher with the increasing of reaction time which the optimum reaction time is 70 minutes with a recovery of 81.13% lithium. The total recovery value of the lithium extracting process from synthetic mineral until it becomes Li2CO3 is at 8.43%.
Depok: Fakultas Teknik Universitas Indonesia, 2013
S53036
UI - Skripsi Membership  Universitas Indonesia Library
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Rohib
Abstrak :
Perkembangan dunia elektronika dan kendaraan bermotor berbasis tenaga baterai beberapa tahun ini meningkat pesat dan diyakini akan terus berkembang dimasa-masa yang akan datang sehingga kebutuhan akan bahan baku baterai pun meningkat dari tahun ke tahun. Salah satu bahan baku baterai yang dinilai paling baik adalah logam Litium (Li). Litium dipilih diantaranya karena memiliki sifat elektropositifnya yang tinggi, ringan dan kemampuan penyimpanan energinnya yang tidak menurun ketika proses pengisian kembali belum penuh namun sudah diputus (anti memory effect). Penelitian ini dilakukan untuk mengekstraksi Litium dari mineral Sugilite dengan menggunakan metode roasting dengan dicampurkan K2SO4 dan water leaching serta mengetahui pengaruh suhu roasting dan perbandingan cairan : padatan pada saat proses leaching . Untuk karakterisasi sampel menggunakan X- RD yang dilengkapi dengan software X-RD Match dan JCPDS, X-RF, EDS, STA dan AAS. Penambahan K2SO4 pada mineral sugilite memberikan peningkatan peyerapan panas sebesar 14,110C dan ΔH energi sebesar 7,7595 J/g. Hasil ekstraksi optimum didapatkan nilai recovery sebesar 26,8 ppm yang dilakukan pada suhu roasting 900 0C dan perbandingan padat : cair = 2,5:1. ......Development of the electronic world and motor vehicle based battery power increased rapidly in recent years and is believed will be continue to grow in the future, And because of that the needs of the raw materials for batteries has increased from year to year. One of the raw material is considered as the best battery is Lithium (Li). Lithium is chosen because it has high electropositive, light and energy storage capability is not back down when the charging process is not full yet been disconnected (anti memory effect). This study was conducted to extract Lithium from mineral Sugilite using roasting method with K2SO4 and water leaching. Variables used to deterrmine this study are the effect of roasting temperature and ratio of liquid : solid in leaching process. For characterization of sample using X-RD is equipped with X-RD Match software and JCPDS, X-RF, EDS, STA and AAS. The addition of K2SO4 on Sugilite cause the heat absorption increased to 14.110C and >H energy 7.7595 J /g. Results obtained optimum extraction got recovery value of lithium is 26.8 ppm. This result perfomed at a temperature of 9000C and ratio roasting solid : liquid = 2.5 : 1.
Depok: Fakultas Teknik Universitas Indonesia, 2013
S53027
UI - Skripsi Membership  Universitas Indonesia Library
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Wildan Nugraha
Abstrak :
Telah dilakukan ekstraksi lihium karbonat dari mineral sintetis campuran Li2OAl2O3-SiO2. Mineral sintetis terbentuk dari campuran senyawa Li2O, Al2O3 dan SiO2 yang dikalsinasi pada suhu 1200 oC selama 90 menit menghasilkan mineral menyerupai β-spodumene. Pada awalnya dilakukan pelindian terhadap mineral sintetis menggunakan Na2CO3 pada sebuah autoclave. Dilanjutkan karbonasi dengan pengaliran gas CO2 hingga mendapatkan larutan LiHCO3. Kemudian larutan dikeringkan untuk mendapatkan lithium karbonat. Hasilnya, dengan meningkatnya rasio Na:Li pada saat pelindian, perolehan Li yang didapatkan semakin tinggi namun kadar Li2CO3 yang dihasilkan semakin rendah. Perolehan terbesar terjadi pada rasio Na:Li 1,6 dengan nilai 73,3%. Kadar Li2CO3 terbesar terjadi pada rasio Na:Li 0,8 dengan nilai 60,6%. Estimasi rasio Na:Li optimum pada proses ini adalah 0,93 untuk mendapatkan nilai perolehan Li dan kadar Li2CO3 sebesar 48%.
In this work, extraction of lithium carbonate from Li2O-Al2O3-SiO2 mixture has been simulated. Synthetic mineral was made by Li2O, Al2O3 and SiO2 mixture and calcinated at 1200 oC 90 minutes to form β-spodumene like minerals. Then, synthetic mineral was leached by Na2CO3 at an autoclave reactor. Followed by carbonation with CO2 gas flow to get LiHCO3. The solution then dried to recover lithium carbonate. The results showed that there has been an increase of lithium recovery along with the increase of Na:Li ratio in leaching stage. But there has been a decrease of lithium carbonate grade in the product. Highest lithium recovery obtained by 1,6 Na:Li ratio with 73,3%. Highest lithium carbonate grade obtained by 0,8 Na:Li ratio with 60,6%. Estimation optimum value of Na:Li ratio in this process was 0,93 to obtain 48% lithium recovery and lithium carbonate grade value.
Depok: Universitas Indonesia, 2014
S53948
UI - Skripsi Membership  Universitas Indonesia Library
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Johansyah
Abstrak :
Litium titanat (Li4Ti5O12) merupakan kandidat yang menjanjikan sebagai anoda baterai Lithium-ion. Litium titanat disintesis menggunakan metode solid state dengan mencampurkan TiO2 xerogel yang dibuat dengan metode sol gel dan litium karbonat (Li2CO3) komersil. Dalam penelitian ini digunakan tiga variasi penambahan kadar massa Li2CO3, yaitu 0% (sampel LTO 1), 50% (sampel LTO 2), dan 100% (sampel LTO 3) melebihi stoikiometri. Karakterisasi menggunakan pengujian XRD, FESEM, UV-vis spectroscopy, dan BET telah dilakukan untuk mengetahui pengaruh kadar litium berlebih terhadap struktur, morfologi, dan energi celah pita sampel. Hasil penelitian menunjukkan bahwa ukuran kristalit, ukuran diameter partikel, energi celah pita, dan luas permukaan masing-masing sampel berturut-turut adalah 8,27 nm, 8,44 μm, 3,88 eV untuk sampel LTO 1; 8,22 nm, 8,56 μm, 4,02 eV, 22,529 m2/gr untuk sampel LTO 2; 4,76 nm, 2,07 μm, 4,12 eV, 16,804 m2/gr untuk sampel LTO 3. Selain itu, litium berlebih yang digunakan dalam sintesis Li4Ti5O12 menyebabkan terbentuknya pengotor TiO2 rutile dan Li2TiO3. Senyawa Li4Ti5O12 hanya terbentuk pada sampel LTO 1 dan LTO 2. Untuk mensintesis senyawa Li4Ti5O12 menggunakan metode solid state tanpa menghasilkan pengotor dapat mengacu pada diagram fasa Li2O-TiO2 (28,64% mol Li2O-71,36% mol TiO2).
Lithium titanate (Li4Ti5O12) is a promising candidate for lithium ion battery anode. Lithium titanate was synthesized by solid state method using xerogel TiO2 was prepared by sol gel method and commercial lithium carbonate (Li2CO3). This research varies the content of Li2CO3 addition, 0% (sample LTO 1), 50% (sample LTO 2), and 100% (sample LTO 3) Li2CO3 mass excess. Characterization using XRD, FESEM, UV-vis spectroscopy, and BET testing was performed to observe the effect of adding lithium excess in structure, morphology, and band gap energy. The results show that crystallite size, particle diameter, band gap energy, and surface area of each sample is 8,27 nm, 8,44 μm, 3,88 eV for sample LTO 1; 8,22 nm, 8,56 μm, 4,02 eV, 22,529 m2/gr for sample LTO 2; 4,76 nm, 2,07 μm, 4,12 eV, 16,804 m2/gr for sample LTO 3. Furthermore, the excess of lithium used for Li4Ti5O12 synthesis cause the formation of impurity compound such as rutile TiO2 and Li2TiO3. Li4Ti5O12 compound was successfully syntesized in sample LTO 1 and LTO 2. In order to synthesis pure Li4Ti5O12 without any impurities using solid state method, Li2O-TiO2 phase diagram (28,64% mol Li2O-71,36% mol TiO2) can be used as a reference.
Depok: Fakultas Teknik Universitas Indonesia, 2014
S57004
UI - Skripsi Membership  Universitas Indonesia Library
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Slamet Priyono
Abstrak :
Sintesis serbuk Li4Ti5O12 yang didoping atom Al dan Na untuk material anoda pada baterai ion lithium telah berhasil dilakukan dengan metode reaksi padat. Doping Al pada Li4Ti5O12 bertujuan untuk menaikkan konduktifitas ionik dan memperkuat struktur sedangkan doping Na bertujuan untuk menurunkan tegangan operasi. Pendopingan dilakukan dengan mengikuti persamaan Li(4-(x/3+y))AlxNayTi(5-2x/3)O12 (x=0; 0,025; 0,05; 0.075 dan y= 0;1) dimana atom Al mensubtitusi Ti dan Li sedangkan atom Na mensubtitusi Li. Sintesis dilakukan melalui metoda metalurgi serbuk dengan menggunakan Li2CO3, TiO2-anatase, Al2O3 and Na2CO3 sebagai bahan baku. Pada penelitian ini, pengaruh subtitusi Na dan Al dalam Li4Ti5O12 terhadap struktur, morphologi, ukuran partikel, surface area dan performa elektrokimia diteliti secara detil. Hasil penelitian menunjukkan bahwa doping ion Al pada Li4Ti5O12 tidak merubah struktur kristal Li4Ti5O12. Hasil FTIR menkonfirmasi tidak adanya perubahan struktur spinel pada gugus khas ketika didoping Al, dengan meningkatnya doping Al membuat tekstur butir menjadi berpori, ukuran partikel menurun dengan ukuran terkecil 20,32 μm, surface area meningkat dengan nilai tertinggi 8,25 m2/gr, konduktifitas ionik meningkat dengan konduktifitas terbaik adalah 8,5 x 10-5 S/cm, tegangan kerja sekitar 1,55 V dan kestabilan siklus terbaik diperoleh pada doping Al 0,025 dengan kapasitas maksimum 70 mAh/g. Sedangkan doping Na dalam Li4Ti5O12 menyebabkan perubahan struktur dengan terbentuk 3 phasa baru yaitu NaLiTi3O7, Li4Ti5O12, dan Li2TiO3. Perubahan struktur juga dikonfirmasi dengan perubahan gugus khas hasil analysis FTIR. Sedangkan kenaikan doping Al menyebabkan phasa NaLiTi3O7 semakin dominan, tekstur butiran menjadi halus, ukuran partikel menurun dengan ukuran terkecil 30,89 μm, surface area menurun, konduktifitas ionic stabil pada 2,5 x 10-5 S/cm, potensial kerja di 1,3 V dan 1,55V, kestabilan struktur didapat pada doping Al 0,05 dengan kapasitas 90 mAh/g. Secara keseluruhan menunjukkan bahwa penambahan doping Al mampu meningkatkan konduktifitas ionik dan kestabilan siklus dan doping Na menurunkan tegangan kerja. ...... Synthesis of Li4Ti5O12 powder doped by Al and Na atoms for lithium ion battery anodes had been carried out using solid state reaction. Al doped on Li4Ti5O12 aim is to increase the ionic conductivity and strengthen the structure of Li4Ti5O12 while Na doped aimed is to decrease the operating voltage. Al and Na doped on Li4Ti5O12 had been carried out by following equation Li(4 - (x / 3 + y))AlxNayTi(5-2x/3)O12 (x = 0; 0,025; 0.05, 0.075 and y = 0, 1) where the Al atoms substitute Ti and Li while Na substituting Li atoms. Synthesis is conducted through a solid state reaction by using Li2CO3, TiO2-anatase, Al2O3 and Na2CO3 as raw materials. In this study, the effects of substitution of Na and Al in Li4Ti5O12 on the structure, morphology, particle size, surface area, and electrochemical performance were deep studied. The results showed that the Al doped on the Li4Ti5O12 was not change crystal structure of Li4Ti5O12. FTIR results confirmed that the absence of changes spinel structure in fingerprint region when doped Al, with increasing Al doped make textures porous grains, particle size decreases to 20.32 μm, surface area increases with highest value of 8.25 m2/gr, conductivity is increased with the best conductivity 8.5 x 10-5 S/cm, , the working voltage of about 1.55 V and the best cycle stability was obtained on doping Al 0.05 and the maximum capacity is 70 mAh/g. While doping Na in Li4Ti5O12 caused structural changes to the three phases formed NaLiTi3O7, Li4Ti5O12, and Li2TiO3. Tranformation on the structure is also confirmed by the changes in the fingerprint region with FTIR analysis. While the increase in Al doping causes NaLiTi3O7 phase become dominant, texture of granular becomes bigger and smoother, the particle size decreases to 30.89 μm, surface area decreases, the ionic conductivity was stable at 2.5 x 10-5 S/cm, The working potential in 1, 3 V and 1.55 V, the stability of the structure obtained on doping Al 0.05 and the maximum capacity of 90 mAh/g. Overall showed that the addition of Al doped can improve the ionic conductivity while stability of the cycle and the Na doped decrease the working voltage.
Depok: Fakultas Teknik Universitas Indonesia, 2014
T42630
UI - Tesis Membership  Universitas Indonesia Library
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Ratna Permata Sari
Abstrak :
[Telah dilakukan peningkatan konduktivitas listrik LiFePO4 dengan metode penambahan material logam nano Cu dan CNTs. Metode ini menjadi pilihan yang menarik karena mudah dan murah dalam proses pembuatannya. Proses sintesis dilakukan dengan mencampur serbuk LiFePO4 (komersil) dengan variasi presentase berat nano tembaga (komersil) 0, 1, 3, 5, 7 wt. % dan 5 wt. % nano karbon (komersil) kemudian di proses vacuum mixing dan film applicator. Pengujian XRD, SEM dan EDX dilakukan pada serbuk yang diterima untuk mengkonfirmasi fasa, ukuran butir serta ada tidaknya impurities. Hasil XRD dan EDX pada serbuk nano Cu menunjukkan bahwa telah terjadi oksidasi dan terbentuk menjadi CuO dan Cu2O, serta ditemukan adanya impurities elemen S sebesar 8.5 wt. %. Komposisi fasa yang dihasilkan dari proses penambahan didapat dari menganalisis pola difraksi XRD menunjukkan bahwa fasa yang terbentuk adalah LiFePO4 namun ditemukan adanya impurities berupa Cu4O3 pada variasi penambahan 80 wt. % LiFePO4, 5 wt. % Cu, 5 wt. % C, dan 10 wt. % PVDF. Konduktivitas listrik diuji material katoda LiFePO4 dengan EIS, dan hasil uji menunjukkan bahwa konduktivitas listrik LiFePO4 meningkat seiiring dengan penambahan nano Cu namun tidak terlalu signifikan (dalam satu orde), hal ini dikarenakan efek oksidasi pada Cu. Pada variasi penambahan nano C dan nano Cu terjadi peningkatan sebesar 3 orde dengan nilai konduktivitas sebesar 8.4 x 10-5 S/cm pada variasi penambahan 80 wt. % LiFePO4, 5 wt. % Cu, 5 wt. % C. Penambahan nano karbon pada LiFePO4 lebih efektif dalam peningkatan konduktivitas dibandingkan dengan penambahan nano Cu dikarenakan efek oksidasi pada Cu yang tidak dapat dihindari. Morfologi material katoda dan distribusi nano Cu dan nano karbon dianalisis menggunakan SEM/EDX, menunjukkan material yang dicampur pada variasi penambahan nano Cu cukup homogen, struktur butir spherical, sedangkan pada variasi penambahan nano Cu dan nano karbon struktur butir polyhedral dengan ukuran butir berada pada rentang 100- 500 nm. Struktur butir ini mempengaruhi hasil cole plot dimana pada variasi penambahan Cu terbentuk semicircle sedangkan pada penambahan nano C tidak;Improved of Electrical conductivity of LiFePO4 with the method of adding Cu Nano metal material and CNTs has been done. This method is an attractive option because it is easy and inexpensive in the manufacturing process. Synthesis process is done by mixing the powder LiFePO4 (commercial) with a variation of the percentage by weight of Nano copper (commercial) 0, 1, 3, 5, 7 wt. % and 5 wt. % CNTs (commercial) and then process in vacuum mixing and film applicator. Testing XRD, SEM and EDX performed on the powder to confirm the phase, grain size and the presence or absence of impurities. Results of XRD and EDX on Nano Cu powder showed that there had been oxidation and formed into CuO and Cu2O, and discovered the existence of impurities elements S of 8.5 wt. %. Phase composition as the result from adding process obtained with analyzing the XRD diffraction pattern showed that the phase formed is LiFePO4 yet found any impurities in the form of Cu4O3 on variations LiFePO4 addition of 80 wt. %, 5 wt. % Cu, 5 wt. % C, and 10 wt. % PVDF. The electrical conductivity of LiFePO4 cathode material was tested by EIS, and the results showed that the electrical conductivity of LiFePO4 increased with the addition of Nano-Cu but not too significant (still on the same order), this is because the effects of oxidation on Cu. On the addition of Nano C and Nano Cu variation there is an increase of 3 order with conductivity value 8.4 x 10-5 S / cm at variations LiFePO4 addition of 80 wt.%, 5 wt.% Cu, 5 wt.% C. The addition of CNTs is more effective in LiFePO4 conductivity increase, compared to the addition of Nano-Cu due to the effects of oxidation on Cu are unavoidable. Cathode material morphology and distribution of CNTs and Nano Cu analyzed using SEM / EDX, showed mixed material on the variation of the addition of Nano Cu quite homogenous, spherical grain structure, while the variation of the addition of Nano Cu and CNTs structures polyhedral grains with a grain size in the range 100-500 nm. This affects the grain structure results in a variation of Cole plot where the addition of Cu is formed semicircle, while the addition of Nano C is not.;Improved of Electrical conductivity of LiFePO4 with the method of adding Cu Nano metal material and CNTs has been done. This method is an attractive option because it is easy and inexpensive in the manufacturing process. Synthesis process is done by mixing the powder LiFePO4 (commercial) with a variation of the percentage by weight of Nano copper (commercial) 0, 1, 3, 5, 7 wt. % and 5 wt. % CNTs (commercial) and then process in vacuum mixing and film applicator. Testing XRD, SEM and EDX performed on the powder to confirm the phase, grain size and the presence or absence of impurities. Results of XRD and EDX on Nano Cu powder showed that there had been oxidation and formed into CuO and Cu2O, and discovered the existence of impurities elements S of 8.5 wt. %. Phase composition as the result from adding process obtained with analyzing the XRD diffraction pattern showed that the phase formed is LiFePO4 yet found any impurities in the form of Cu4O3 on variations LiFePO4 addition of 80 wt. %, 5 wt. % Cu, 5 wt. % C, and 10 wt. % PVDF. The electrical conductivity of LiFePO4 cathode material was tested by EIS, and the results showed that the electrical conductivity of LiFePO4 increased with the addition of Nano-Cu but not too significant (still on the same order), this is because the effects of oxidation on Cu. On the addition of Nano C and Nano Cu variation there is an increase of 3 order with conductivity value 8.4 x 10- 5 S / cm at variations LiFePO4 addition of 80 wt.%, 5 wt.% Cu, 5 wt.% C. The addition of CNTs is more effective in LiFePO4 conductivity increase, compared to the addition of Nano-Cu due to the effects of oxidation on Cu are unavoidable. Cathode material morphology and distribution of CNTs and Nano Cu analyzed using SEM / EDX, showed mixed material on the variation of the addition of Nano Cu quite homogenous, spherical grain structure, while the variation of the addition of Nano Cu and CNTs structures polyhedral grains with a grain size in the range 100-500 nm. This affects the grain structure results in a variation of Cole plot where the addition of Cu is formed semicircle, while the addition of Nano C is not., Improved of Electrical conductivity of LiFePO4 with the method of adding Cu Nano metal material and CNTs has been done. This method is an attractive option because it is easy and inexpensive in the manufacturing process. Synthesis process is done by mixing the powder LiFePO4 (commercial) with a variation of the percentage by weight of Nano copper (commercial) 0, 1, 3, 5, 7 wt. % and 5 wt. % CNTs (commercial) and then process in vacuum mixing and film applicator. Testing XRD, SEM and EDX performed on the powder to confirm the phase, grain size and the presence or absence of impurities. Results of XRD and EDX on Nano Cu powder showed that there had been oxidation and formed into CuO and Cu2O, and discovered the existence of impurities elements S of 8.5 wt. %. Phase composition as the result from adding process obtained with analyzing the XRD diffraction pattern showed that the phase formed is LiFePO4 yet found any impurities in the form of Cu4O3 on variations LiFePO4 addition of 80 wt. %, 5 wt. % Cu, 5 wt. % C, and 10 wt. % PVDF. The electrical conductivity of LiFePO4 cathode material was tested by EIS, and the results showed that the electrical conductivity of LiFePO4 increased with the addition of Nano-Cu but not too significant (still on the same order), this is because the effects of oxidation on Cu. On the addition of Nano C and Nano Cu variation there is an increase of 3 order with conductivity value 8.4 x 10- 5 S / cm at variations LiFePO4 addition of 80 wt.%, 5 wt.% Cu, 5 wt.% C. The addition of CNTs is more effective in LiFePO4 conductivity increase, compared to the addition of Nano-Cu due to the effects of oxidation on Cu are unavoidable. Cathode material morphology and distribution of CNTs and Nano Cu analyzed using SEM / EDX, showed mixed material on the variation of the addition of Nano Cu quite homogenous, spherical grain structure, while the variation of the addition of Nano Cu and CNTs structures polyhedral grains with a grain size in the range 100-500 nm. This affects the grain structure results in a variation of Cole plot where the addition of Cu is formed semicircle, while the addition of Nano C is not.]
Fakultas Teknik Universitas Indonesia, 2015
T43699
UI - Tesis Membership  Universitas Indonesia Library
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Achmad Subhan
Abstrak :
Telah dilakukan penelitian sintesa Li4Ti5O12 untuk aplikasi komponen anoda pada baterai lithium keramik. Sintesa dilakukan dengan metoda SSR (solid state reaction) dari bahan serbuk Li2CO3 dan TiO2. Percobaan dilakukan untuk mendapatkan optimasi parameter sintesa, yaitu dengan melakukan variasi suhu sinter dan lama waktu penahanan sinter. Proses diawali dengan kalsinasi pada suhu 700oC selama 1 jam. Kemudian dilakukan penggerusan dengan mortal hingga lolos 200 mesh. Sebelum disinter terlebih dahulu serbuk dipastakan dalam larutan metanol 99% sebagai pendispersi sehingga diharapkan campuran homogen. Variasi suhu sinter dilakukan pada suhu 750°C, 800°C, 850°C, 900°C dan 950°C masingmasing selama 2 jam. Sedangkan variasi waktu dilakukan pada suhu sinter 850°C dengan variasi waktu 1jam, 4 jam dan 8 jam. Identifikasi fasa yang terbentuk dilakukan dengan XRD, struktur mikro dengan SEM/EDX, konduktifitas grain dan grain boundary dengan spektrum impedansi AC. Untuk mengetahui porositas dan densitas dilakukan untuk pengujian dengan mengacu pada standar ASTM C 20-92. Sifat mekanik bahan dipelajari dari uji kekerasan mikrohardness dengan metoda Vickers. Dari penelitian ini didapatkan konduktifitas listrik tertinggi adalah ~ 1.0 10-7 S/cm dihasilkan dari suhu 850oC selama 2 jam. Prototip baterai lithium keramik telah dibuat LTO/LATP/LMO dengan tambahan elektrolit LiClO4. Tegangan sel mampu mencapai 2.5 V pada first charging, sementara pengujian kapasitas charge/discharge menunjukkan kapasitas discharge maksimal hanya 7%. Sel baterai juga menunjukkan gejala self discharge.
Li4Ti5O12 as anode material for lithium ceramic battery has been synthesized. Synthesis has been done by solid state reaction (SSR) method with the powder of Li2CO3 and TiO2 as starting materials. Research has been done to get optimum parameters during the synthesizing anode material by varying sinter temperature and time. Synthesis of anode material was initiated by calcination process, where the mixture of Li2CO3 and TiO2 was heated at 700oC for 1 hour. The obtained material from this step was further ground and sieved 200 mesh. Methanol with a purity of 99% was added to the powder after grinding. The purpose of this step is to get a homogene mixture. The sinter process of this homogene mixture was done by heating this material with temperature variation of 750°C, 800°C, 850°C, 900°C and 950°C for 2 hours each. Varying sinter time of 1, 4, and 8 hours was done during sintering anode material at 850°C. The obtained phases from sintering was done by XRD, microstructure by SEM/EDX, and conductivity of grain and grain boundary by AC Impedance Spectroscopy. The porosity and density of the obtained material were determined, referring to ASTM C 20-92 standard measurement. The mechanical property was studied by microhardness with vickers method. This research showed that the anode material has a high electrical conductivity around 1.0 10-7 S/cm by sintering at 850oC for 2 hours. Prototype of lithium ceramic battery LTO/LATP/LMO was made with an addition of LiClO4. Battery performance was analyzed by charge/discharge capacity test. Cell voltage at first cycle was excellently reach about 2.5 Volt. It showed that the maximum discharge capacity of the cell was only 7% from charge capacity. The cell also showed a self discharge phenomenon.
Depok: Fakultas Teknik Universitas Indonesia, 2011
T28730
UI - Tesis Open  Universitas Indonesia Library
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Tin Rahmiati
Abstrak :
Baterai lithium sebagai kandidat komponen anoda mempunyai keunggulan dibanding material baterai lainnya. Anoda Li4Ti5O12 mempunyai sifat zero strain material, yaitu mempunyai struktur yang tetap pada proses charging/discharging dengan siklus yang berulang-ulang. Artinya, anoda Li4Ti5O12 mempunyai kapasitas yang tinggi pada siklus charging/discharging yang lama sehingga membuat baterai lebih tahan lama. Pembuatan anoda baterai Li4Ti5O12 menjadi komposit dengan keramik gelas sebagai matriks menghasilkan anoda baterai Li4Ti5O12 yang mempunyai sifat mekanis yang baik. Penambahan elektrolit Li2O sebagai dopan meningkatkan konduktivitas baterai. Konduktivitas yang diukur dengan metode EIS (Electrochemical Impedans Spectrometry) menunjukkan adanya konduktivitas bulk dan konduktivitas batas butir (grain boundary). Konduktivitas bulk diperoleh dari konduktivitas Li4Ti5O12 yang menunjukkan konduktivitas yang relatif tetap sehingga penambahan Li2O tidak berpengaruh terhadap Li4Ti5O12. Hal ini membuktikan bahwa Li2O tidak masuk ke dalam struktur Li4Ti5O12. Konduktivitas batas butir mengalami perubahan seiring dengan penambahan Li2O sebesar 2%, 4%, 6%, 8% dan 10%. Konduktivitas batas butir optimum diperoleh dari penambahan 4% Li2O yaitu sebesar 2,48x10-6 S/cm. Konduktivitas batas butir menunjukkan konduktivitas total dari anoda baterai lithium karena proses interkalasi saat charging/discharging lebih mudah terjadi pada batas butir. Dengan demikian, penambahan elektrolit Li2O sebagai dopan meningkatkan konduktivitas dari komposit keramik komponen anoda baterai Li4Ti5O12. ......Lithium batteries have an excelent characteristic if we compare with other batteries material. Li4Ti5O12 as an anode, have zero strain material characteristic, which stability structure in charging/discharging process with long cycle time. It means, Li4Ti5O12 anode have high capacity in long cycle time so that occur approve life time of batteries. To produce lithium batteries become composite with glass ceramic as a matrix make anode Li4Ti5O12 batteries have good mechanical properties. Addition of electrolyte Li2O as a dopan can improve batteries conductivity. Measuring conductivity use EIS method (Electrochemical Impedans Spectrometry) indicate bulk conductivity and grain boundary conductivity. Bulk conductivity shows Li4Ti5O12 conductivity indicate relative fix so addition of Li2O not influence to Li4Ti5O12. That is approve Li2O not entered to Li4Ti5O12 structure. Grain boundary conductivity has change when added 2, 4, 6, 8 and 10 % Li2O. Grain boundary optimum conductivity get with addition of 4% Li2O which 2,48x10-6 S/cm. Grain boundary conductivity shows total conductivity from anode lithium batteries because of intercalation process when charging/discharging at grain boundary is more easily. So, addition of electrolyte Li2O as a dopan can improve conductivity of ceramic composites anode Li4Ti5O12 baterries componen.
Depok: Fakultas Teknik Universitas Indonesia, 2011
T29867
UI - Tesis Open  Universitas Indonesia Library
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