Density modulated multilayer silicon thin films for lithium-ion batteries
Başlık çevirisi mevcut değil.
- Tez No: 401512
- Danışmanlar: DR. TANSEL KARABACAK
- Tez Türü: Doktora
- Konular: Fizik ve Fizik Mühendisliği, Physics and Physics Engineering
- Anahtar Kelimeler: Belirtilmemiş.
- Yıl: 2014
- Dil: İngilizce
- Üniversite: Unıversıty Of Arkansas At Lıttle Rock
- Enstitü: Yurtdışı Enstitü
- Ana Bilim Dalı: Belirtilmemiş.
- Bilim Dalı: Belirtilmemiş.
- Sayfa Sayısı: Belirtilmemiş.
Özet
Özet yok.
Özet (Çeviri)
Graphite is currently the most common commercial anode material for Li-ion batteries which has a theoretical capacity value of 372 mAh/g. Since this value has already been achieved and does not fulfill the requirements of new technologies, replacement of carbon with new anode materials has become a necessity. Recently, silicon (Si) has been proposed as a promising anode material because of its high theoretical capacity (~3580-4200 mAh/g), which is the highest known value among all materials in nature so far. However, Si anode materials suffer from several problems which have prevented its commercial use. The most significant problem with bulk Si is its more than ~400% volume change during the insertion/extraction of lithium ions. This high volumetric expansion/contraction of in Si structure causes considerably high stress followed by cracking, pulverization, and the loss of electrical contact; and finally results in capacity fading and failing. In order to achieve higher cycling performance without pulverization and delamination, the mechanical failure due the volume change must be tolerated. Studies reported in the literature suggested several approaches to overcome the problems associated with Si/Li intercalation. Using active and inactive additives, coatings on Si, Si-C composites, and composite nanostructures and films have been considered for this purpose. However, these methods were successful to a certain extent addressing only some of the problems, yet not being able to solve the major challenges with Si. In this work, we developed a new density modulated multilayer Si thin film anode approach, which can provide a robust high capacity electrode for Li-ion batteries. Our results showed that these films can provide a high coulombic efficiency up to 99% and reversible specific capacity as high as ~1700 mAh g-1 after 50 cycles. Low-density layers are believed to be performing as compliant layers during volume change making the films more durable compared to conventional Si film anodes. Several materials such as Cr and Ni were also tested as adhesion layers to overcome the delamination problem. The results of this work can lead to Si thin film anode materials with superior capacity and mechanical stability compared to conventional Si anodes.
Benzer Tezler
- Günümüzde ısı değiştirici imalatında kullanılan yöntemler
The Methods that is used at fabrication of the heat exchangers
HÜSEYİN ÇEBİ
- Yumuşak hesaplama yöntemlerinin geliştirilmesi ve elektriksel sürücülerdeki uygulamaları
The improvement of soft computing methods and its applications in electric drives
MEHMET KARAKÖSE
Doktora
Türkçe
2005
Elektrik ve Elektronik MühendisliğiFırat ÜniversitesiElektrik-Elektronik Mühendisliği Ana Bilim Dalı
DOÇ.DR. ERHAN AKIN
- Design of a self-aligned, high resolution, low temperature (30 mK - 300 K) magnetic force microscope
Kendiliğinden hizalamalı, yüksek çözünürlüklü, düşük sıcaklık (30 mK - 300 K) manyetik kuvvet mikroskobu tasarımı
ÖZGÜR KARCI
Doktora
İngilizce
2015
Fizik ve Fizik MühendisliğiHacettepe ÜniversitesiNanoteknoloji ve Nanotıp Ana Bilim Dalı
PROF. DR. ŞADAN ÖZCAN
PROF. DR. AHMET ORAL
- OFDM tabanlı temel bant WIMAX fiziksel katman vericinin FPGA üzerinde gerçeklenmesi
Implementation of OFDM based WIMAX physical layer baseband transmitter on FPGA
AHMET TANSU AKTÜRK
Yüksek Lisans
Türkçe
2014
Elektrik ve Elektronik Mühendisliğiİstanbul Teknik ÜniversitesiElektronik ve Haberleşme Mühendisliği Ana Bilim Dalı
DOÇ. DR. MESUT KARTAL
- Synthesis of some functional conducting polymers, characterization, Mott-Schottky analysis and sensor applications
Bazı fonksiyonel iletken polimerlerin sentezi, karakterizasyonu, Mott-Schottky analizi ve sensor uygulamaları
TOLGA KARAZEHİR
Doktora
İngilizce
2017
Polimer Bilim ve Teknolojisiİstanbul Teknik ÜniversitesiPolimer Bilim ve Teknolojisi Ana Bilim Dalı
PROF. DR. ABDÜLKADİR SEZAİ SARAÇ
PROF. DR. MURAT ATEŞ