Refining The Morphology

A project log for WRONG PROJECT 2


MECHANICUSMECHANICUS 08/25/2015 at 19:540 Comments


Here in lies the Blueprint for creating the ultimate Lithium Ion Sulfur Cathode Silicon Anode battery. It is amazing academia does all the scientific work with proper control but hardly ever combines the findings into one work. I will be updating this as I tweak my battery and fill in the blanks. Excerpts and licensing noted where required.

The Electrolyte

A switch to a poly sulfide shuttle is in order as very low decay is possible. The difficulty lies in keeping sulfur out of the anode as I will be using a silicon electrode. The loading of poly-sulfide in the electrolyte keeps sulfur in the cathode from migrating to the anode causing shorter life of the cell. I will be using calcium polysulfide.

Polysulfide shuttle control: Towards a lithium-sulfur battery with superior capacity performance up to 1000 cycles by matching the sulfur/electrolyte loading

Xin-Bing Cheng,Jia-Qi Huang,Hong-Jie Peng,Jing-Qi Nie,Xin-Yan Liu,Qiang Zhang,Fei Wei

Journal of Power Sources


1 May 2014

Copyright © 2013 Elsevier B.V. All rights reserved.

A manganese functionalized zeolite matrix will provide support for the Calcium Poly-sulfide as was used in this paper. The zeolite I will be using is naturally occurring and readily available.

Manganese modified zeolite silicalite-1 as polysulphide sorbent in lithium sulphur batteries

Vida Lapornik,Natasa Novak Tusar,Alenka Ristic,Rajesh Kumar Chellappan,Dominique Foix,Rémi Dedryvère,Miran Gaberscek,Robert Dominko

Journal of Power Sources


15 January 2015

The Anode

A Graphene oxide membrane will be utilized to keep poly-sulfides out of the anode as was demonstrated here. This will also reduce self discharge.

"Lithium–sulfur batteries hold great promise for serving as next generation high energy density batteries. However, the shuttle of polysulfide induces rapid capacity degradation and poor cycling stability of lithium–sulfur cells. Herein, we proposed a unique lithium–sulfur battery configuration with an ultrathin graphene oxide (GO) membrane for high stability. The oxygen electronegative atoms modified GO into a polar plane, and the carboxyl groups acted as ion-hopping sites of positively charged species (Li+) and rejected the transportation of negatively charged species (Sn2–) due to the electrostatic interactions. Such electrostatic repulsion and physical inhibition largely decreased the transference of polysulfides across the GO membrane in the lithium–sulfur system. Consequently, the GO membrane with highly tunable functionalization properties, high mechanical strength, low electric conductivity, and facile fabrication procedure is an effective permselective separator system in lithium–sulfur batteries."

Permselective Graphene Oxide Membrane for Highly Stable and Anti-Self-Discharge Lithium–Sulfur Batteries

Jia-Qi Huang, Ting-Zhou Zhuang, Qiang Zhang*, Hong-Jie Peng, Cheng-Meng Chen, and Fei Wei

† Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China

‡ Key Laboratory of Carbon Materials, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, China

ACS Nano, 2015, 9 (3), pp 3002–3011

DOI: 10.1021/nn507178a

Publication Date (Web): February 18, 2015

Copyright © 2015 American Chemical Society

Reprinted with permission from {Permselective Graphene Oxide Membrane for Highly Stable and Anti-Self-Discharge Lithium–Sulfur Batteries}. Copyright {2015} American Chemical Society.

A MnO2 functionalized Graphene/iMWCNT wrapped reduced diatomaceous earth anode will be made that will resemble this study that had an incredible 1525 mAh per gram capacity, high cycling stability and low resistance. The MnO2 functionalization will help recover some of the limited Li+ intercalation that graphene and iMWCNT are capable of.

A novel bath lily-like graphene sheet-wrapped nano-Si composite as a high performance anode material for Li-ion batteries

Yu-Shi He,a Pengfei Gao,a Jun Chen,b Xiaowei Yang,a Xiao-Zhen Liao,a Jun Yang*a and Zi-Feng Ma*a

Show Affiliations

RSC Adv., 2011,1, 958-960

DOI: 10.1039/C1RA00429H

Received 08 Jul 2011, Accepted 09 Aug 2011

First published online 07 Sep 2011!divAbstract

I will utilize microwave urea assisted reduction instead of calcining the composite at 700 degrees celcius. As is used in this study.

Sunil P. Lonkar, Jean-Marie Raquez, Philippe Dubois, "One-pot Microwave-assisted Synthesis of Graphene/Layered Double Hydroxide (LDH) Nanohybrids", Nano-Micro Lett. 7(3), - (2015).

More information on microwave chemistry, the most powerful energy saving tool in the chemists arsenal. heating processes_JAMD_2010.pdf

I will continue to use chitosan as the binder my first results were very high resistance as I had a loading of around 29% whereas 8% by weight is sufficient. This was exhibited here. Used in a silicon anode an unheard of initial discharge capacity of 4270 mAh g was realized with a stable discharge of 950 mAh per gram thereafter.

Carboxymethyl chitosan: A new water soluble binder for Si anode of Li-ion batteries

Received 17 June 2013, Revised 14 August 2013, Accepted 17 August 2013, Available online 5 September 2013

Another resource for microwave assisted calcination. I could use pre-calcined diatomaceous earth/kieselguhr but then I wont be synthesizing Silicon Carbide and increasing conductivity of the lithium containing silicon.

Rapid Limestone Calcination Using Microwave Assist Technology Morgana Fall, Gibran Esquenazi, Shawn Allan and Holly Shulman, Ceralink Inc.

The Cathode

Metal organic framework, Asphaltenes which contain up to 7% sulfur themselves act as an incredible cathode material allowing adsorption of two lithium ions per sulfur atom. The problem is the Cathode would be too thick using asphaltenes alone as I need twice the number of atoms of sulfur to silicon to balance the electrodes(silicon can store 4 lithium ions as opposed to sulfur's 2). So I will have to add elemental sulfur, the procedure will be to ball mill the asphaltenes, graphene oxide and ox-iMWCNT together to create a nanowrapped sulfur allowing electron flow to the sulfur on discharge.

Will update later sleep calls