Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Novel MOF shell-derived surface modification of Li-rich layered oxide cathode

02.01.2018

Rapid development of portable electronics and electric vehicles requires lithium-ion batteries (LIBs) to have high energy/power density, low cost, good safety and long lifespan. In a commercial LIB, the traditional cathode and anode materials are LiCoO2 and graphite, respectively.

Compared with the commercial graphite (theoretical-capacity 372 mAh g-1), the LiCoO2 has a low specific capacity of 150 mAh g-1 which becomes a big bottleneck of the battery breakthroughs. Among numerous cathode materials, Li-rich layered oxide (LLO) materials have attracted increasing attention as promising candidates because of their high specific capacity (> 250 mAh g-1) and high operating voltage (> 3.5 V vs. Li+/Li). However, an undesired spinel growth in the layered host structure usually occurred from the surface during the long-term cycling, which led to the fast capacity fading and voltage decaying.


This is a schematic illustration of LLO@C&NiCo; Cycling performance and the corresponding Coulombic efficiencies tested at current densities of 0.4 C; SAED patterns of LLO and LLO@C&NiCo after 50 cycles at 0.4 C.

Credit: ©Science China Press

Prof. L. Q. Mai has led a research team at Wuhan University of Technology aiming to improve the electrochemical performance of electrode materials. They have developed a facile and general carbon coating technology [1].

The unique NiCo nanodots decorated carbon shell was constructed on the as-prepared Li1.2Mn0.54Ni0.13Co0.13O2 nanoparticles masterly on this basis [2]. The obtained LLO@C&NiCo cathode exhibits enhanced cycling and rate capability with a capacity retention of 95% after 100 cycles at 0.4 C, 90% after 300 cycles at 2 C and a high capacity of 159 mAh g-1 at 5 C, respectively.

The in-situ X-ray diffraction, electrochemical impedance spectroscopy and selected area electron diffraction analyses after cycling demonstrate that the LLO@C&NiCo as a cathode material for LIBs exhibiting superior electrochemical performances, which is due to its unique protective C&NiCo shell. It promotes the electron conductivity (5 times), reduces the diffusion impedance, provides a robust structure for LLO which suppresses the undesired formation of the spinel phase initiated from the particle surface during cycling, and also protects the surface structure from side reactions at the electrode/electrolyte interface.

###

This research was supported by the National Key Research and Development Program of China (2016YFA0202603) and the National Basic Research Program of China (2013CB934103).

See the articles:

Jiashen Meng, Xiong Liu, Jiantao Li, Qi Li, Chuan Zhao, Linhan Xu, Xuanpeng Wang, Fang Liu, Wei Yang, Xiaoming Xu, Ziang Liu, Chaojiang Niu, and Liqiang Mai. General oriented synthesis of precise carbon-confined nanostructures by low-pressure vapor superassembly and controlled pyrolysis. Nano letters, DOI: 10.1021/acs.nanolett.7b03982 https://doi.org/10.1021/acs.nanolett.7b03982

Zhitong Xiao, Jiashen Meng, Qi Li, Xuanpeng Wang, Meng Huang, Ziang Liu, Chunhua Han, and Liqiang Mai. Novel MOF shell-derived surface modification of Li-rich layered oxide cathode for enhanced lithium storage. Science Bulletin, 2017, Doi : 10.1016/j.scib.2017.12.011

L. Q. Mai | EurekAlert!

More articles from Materials Sciences:

nachricht New materials: Growing polymer pelts
19.11.2018 | Karlsruher Institut für Technologie (KIT)

nachricht Why geckos can stick to walls
19.11.2018 | Jacobs University Bremen gGmbH

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Nonstop Tranport of Cargo in Nanomachines

Max Planck researchers revel the nano-structure of molecular trains and the reason for smooth transport in cellular antennas.

Moving around, sensing the extracellular environment, and signaling to other cells are important for a cell to function properly. Responsible for those tasks...

Im Focus: UNH scientists help provide first-ever views of elusive energy explosion

Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.

Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Optical Coherence Tomography: German-Japanese Research Alliance hosted Medical Imaging Conference

19.11.2018 | Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

 
Latest News

Nonstop Tranport of Cargo in Nanomachines

20.11.2018 | Life Sciences

Researchers find social cultures in chimpanzees

20.11.2018 | Life Sciences

When AI and optoelectronics meet: Researchers take control of light properties

20.11.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>