Volumetric Discharge Capacity 1 A h cm–3 Realized by Sulfur in Carbon Nanotube Sponge Cathodes

In situ chemical oxidation polymerization of pyrrole on the surface of sulfur/multi-walled carbon nanotube particle was carried out to synthesize a novel polypyrrole coated sulfur/multi-walled carbon nanotube (PPy@S/MWCNT) composite. The sulfur/multi-walled carbon nanotube composite (S/MWCNT) was prepared by a facile quasi-emulsion template method in an oil/water system. The ternary PPy@S/MWCNT composite was characterized by elemental analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), and electrochemical measurements. In the composite, polypyrrole works as a conducting matrix as well as a coating agent, confining the active materials within the electrode, while the MWCNT creates a highly conductive and mechanically flexible framework, hence enhancing the electronic conductivity and the rate capability of the material. This ternary composite exhibits stable cyclability, retaining a discharge capacity of 612 mAh g-1 at 0.1 C after 100 cycles. Furthermore, up to 1.5 C rate, the ternary composite still delivered a highly reversible discharge capacity of 463 mAh g-1.

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Biotemplating pores with size and shape diversity for Li-oxygen Battery Cathodes

Scientific Reports ◽

10.1038/srep45919 ◽

2017 ◽

Vol 7 (1) ◽

Cited By ~ 4

Author(s):

Dahyun Oh ◽

Cagla Ozgit-Akgun ◽

Esin Akca ◽

Leslie E. Thompson ◽

Loza F. Tadesse ◽

...

Keyword(s):

Carbon Nanotube ◽

Chemical Synthesis ◽

Performance Improvement ◽

Oxygen Evolution ◽

Discharge Capacity ◽

Pore Volume ◽

Porous Structures ◽

Free Standing ◽

Multiwalled Carbon ◽

Interconnected Pores

Abstract Synthetic porogens provide an easy way to create porous structures, but their usage is limited due to synthetic difficulties, process complexities and prohibitive costs. Here we investigate the use of bacteria, sustainable and naturally abundant materials, as a pore template. The bacteria require no chemical synthesis, come in variable sizes and shapes, degrade easier and are approximately a million times cheaper than conventional porogens. We fabricate free standing porous multiwalled carbon nanotube (MWCNT) films using cultured, harmless bacteria as porogens, and demonstrate substantial Li-oxygen battery performance improvement by porosity control. Pore volume as well as shape in the cathodes were easily tuned to improve oxygen evolution efficiency by 30% and double the full discharge capacity in repeated cycles compared to the compact MWCNT electrode films. The interconnected pores produced by the templates greatly improve the accessibility of reactants allowing the achievement of 4,942 W/kg (8,649 Wh/kg) at 2 A/ge (1.7 mA/cm2).

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Improvement of Charge/Discharge Capacity of Lithium-Air Battery Using Porous Carbon Nanotube Electrode

ECS Meeting Abstracts ◽

10.1149/ma2017-02/52/2168 ◽

2017 ◽

Keyword(s):

Carbon Nanotube ◽

Discharge Capacity ◽

Porous Carbon ◽

Air Battery ◽

Charge Discharge

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The Characteristics of Sulfur Electrode with Carbon Nanotube

Materials Science Forum ◽

10.4028/www.scientific.net/msf.534-536.1509 ◽

2007 ◽

Vol 534-536 ◽

pp. 1509-1512 ◽

Cited By ~ 1

Author(s):

Ho Suk Ryu ◽

Sang Won Lee ◽

Ki Won Kim ◽

Joo Hyun Ahn ◽

Kwon Koo Cho ◽

...

Keyword(s):

Carbon Nanotube ◽

Discharge Capacity ◽

Additive Effect ◽

Plateau Potentials ◽

Optimum Content ◽

Discharge Curve ◽

Discharge Behavior ◽

Sulfur Electrode ◽

First Discharge Capacity ◽

Lithium Sulfur

We investigated on the additive effect of carbon nanotube in the sulfur electrode on the first discharge curve and cycling property of lithium/sulfur cell. The sulfur electrode with carbon nanotube had two discharge plateau potentials and the first discharge capacity about 1200 mAh/g sulfur. The addition carbon nanotube into the sulfur electrode did not affect the first discharge behavior, but improved the cycling property of lithium/sulfur cell. The optimum content of carbon nanotube was 6 wt% of sulfur electrode.

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