Journal of Nanomedicine & Nanotechnology

Improvement of capacity retention of LiMn2O4 using various coatings as a cathode material to LIBs

3^rd International Conference on Nanotek & Expo

December 02-04, 2013 Hampton Inn Tropicana, Las Vegas, NV, USA

Monika Michalska, Bartosz Hamankiewicz, Dominika Ziołkowska, Michał Krajewski, Mariusz Andrzejczuk, Ludwika Lipinska and Andrzej Czerwinski

Accepted Abstracts: J Nanomed Nanotechnol

Abstract:

The market of LIBs develops rapidly. These batteries are commonly used in portable electronic devices, such as: cell phones, notebooks, tablets, ipods, media players, as well as in hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), owing to its high energy density and working voltage, long lifecycle, small dimensions and weight. Especially, the last applications require large format batteries and their safety becomes a key issue. Lithium manganese oxide (LiMn 2 O 4 ) of spinel structure has been extensively studied as a cathode material for Li-ion batteries. Application of LiMn 2 O 4 has several advantages like: low cost, easy preparation, non-toxicity, high potential (4V vs. Li metal), a satisfactory capacity, high-energy density, low self-discharge and high thermal and structural stability. In spite of these advantages, LiMn 2 O 4 suffers from a serious capacity fading during charge-discharge cycles, which is unacceptable in commercial applications. This problem can be caused by several factors: manganese dissolution, electrolyte decomposition at high potentials, the Jahn-Teller distortion at the state of a deep discharge and lattice instability. In order to resolve this complicated problem, in our work, we investigated and compared the electrochemical performance of LiMn 2 O 4 coated by various; metallic (i.e. Ag), carbon (i.e. grapheme oxide) and ceramic oxides (i.e. SiO 2 ). The wet chemical method was used to modify the surface grains of LMO. The crystal structures of samples were characterized by XRD and Raman spectroscopy. The particle size and morphology were observed by: SEM, TEM. Also, the electrochemical tests were performed. The results of these measurements will be presented at the conference.

Biography :

Monika Michalska is a Vice President of NANONET Foundation, non-profit organization. She is also Editor-in-Chief on NANONET Newsletter. She is a Research Assistant at the Institute of Electronic Materials Technology. She specializes in the field of materials science/chemistry/nanotechnology, including in particular the preparation of electrode (for cathode and anode) nanomaterials for lithium ion batteries and supercapacitors using various chemical methods. She also synthesizes composites with ceramic oxide or metallic materials and with carbon coatings: with graphene flakes, graphene oxide and reduced graphene oxide (which are produced in our lab oratory)