Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Cobalt Poor and Rich lixNi1-yCoyO2 Layered Materials For Li-Ion Battery Application

29.04.2015

Researchers from the Institute of Science, University Teknologi MARA Selangor conducted a study into the possibility of using new and cost effective compounds in Li ION battery application.

Layered compounds are being investigated extensively due to their high theoretical specific capacities and relatively good cyclability. The electrochemical performance of a layered cathode material depends, to some extent, on the lattice parameters and structural stability of the crystal framework as well as, to a large extent, on the cation ordering of the compounds.


Copyright : Wikimedia

Lithium cobalt oxide (LiCoO2) is an excellent cathode material but expensive, toxicity and not abundant in nature. Therefore, it is logical to produce materials with less Co content for commercial application.

LiNiO2 has the advantage of being cheaper. However, it is unstable and do not exhibit good electrochemical properties. Substitution of Co with Ni may improve the structural stability of LixNi1-yCoyO2 system and may reduce production cost due to the least of Co content.

Many groups of researchers have attempted to synthesize some stoichiometries of LixNi1-yCoyO2, but their XRD results show the presence of impurities. Other researchers have produced hexagonal structure but with poor cation ordering with high (104) peaks relative to the (003) peak.

In this work, layered LixN1-yCoyO2 (x= 1.0, 1.05, 1.1: y= 0.0, 0.1, ...., 0.5) via a novel self-propagating combustion synthesis and its electrochemical properties are investigated. The most obvious advantage of using this combustion route is the ease of the method and speed of the reaction which is over in a few seconds. The precursors are already in the dry form, and, subsequently, the thermal annealing can be done directly without further drying or precalcination process.

Therefore, the synthesis method has the advantage of producing homogeneous materials with the resulting final products free from impurities, even for the Ni-rich stoichiometries. Simultaneous Thermogravimetric Analysis (STA), X-Ray Diffraction (XRD) , Field Emission Scanning Electron Microscopy (FESEM) and Energy DIspersive X-Ray Spectroscopy were used to characterize all the materials. The characterization of all samples shows pure and single phase layered hexagonal structured materials obtained at 700 degree celcius for 24 h, 48 h and 72 h with a polyhedral like morphology. This means that the Ni-ions have been successfully substituted in the LiCoO2 structure.

It can be clearly observed that all of the fingerprint peaks, namely, (003), (101), (006), (012), (104), (018), and (110) are easily identifiable in all of the XRD patterns. All the diffraction peaks can be indexed with alfa-NaFeO2-type structure based on the hexagonal crystal system with R-3m space group. They are isostructural with LiNiO2 and LiCoO2 phases as compared with the XRD patterns in the ICDD database. The EDX results give atomic percent for each sample and agreeable to calculated synthesized values, from cyclic voltammetry, the maximum voltage can reached up to 5.0 V and minimum voltage is 2.3 V.

The LixNi1-yCoyO2 materilas show good promise as cathode materials. The best performance of cathode materials are LiNi0.5Co0.5O2 with the specific capacity of 158.2 mAh/g, Li1.05Ni0.6Co0.4O2 with the specific capacity of 155.3 mAh/g, Li1.05Ni0.7Co0.3O2 with the specific capacity of 153.9 mAh/g, Li1.05Ni0.7Co0.3O2 with the specific capacity of 148.1 mAh/g, Li1.1Ni0.6Co0.4O2 with the specific capacity of 145.7 mAh/g, LiNi0.7Co0.3O2 with the specific capacity of the 144.4 mAh/g, Li1.1Ni0.7Co0.3O2 and Li1.1Ni0.5Co0.5O2 with the specific capacity of 142.8 mAh/g.

Professor Dr.
CHE NORLIDA BINTI KAMARULZAMAN
Universiti Teknologi MARA, Selangor
Institute of Science
INSTITUTE OF SCIENCE (IOS)
norlyk@salam.uitm.edu.my

Darmarajah Nadarajah | ResearchSEA
Further information:
http://www.uitm.edu.my
http://www.researchsea.com

Further reports about: Li-Ion LiCoO2 UiTM capacity cathode cathode materials materials synthesis voltage

More articles from Power and Electrical Engineering:

nachricht Electromagnetic water cloak eliminates drag and wake
12.12.2017 | Duke University

nachricht Two holograms in one surface
12.12.2017 | California Institute of Technology

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Plasmonic biosensors enable development of new easy-to-use health tests

14.12.2017 | Health and Medicine

New type of smart windows use liquid to switch from clear to reflective

14.12.2017 | Physics and Astronomy

BigH1 -- The key histone for male fertility

14.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>