MWCNT/V2O5 core/shell sponge for high areal capacity and power density Li-ion cathodes

ACS Nano. 2012 Sep 25;6(9):7948-55. doi: 10.1021/nn302417x. Epub 2012 Aug 15.

Abstract

A multiwall carbon nanotube (MWCNT) sponge network, coated by ALD V(2)O(5), presents the key characteristics needed to serve as a high-performance cathode in Li-ion batteries, exploiting (1) the highly electron-conductive nature of MWCNT, (2) unprecedented uniformity of ALD thin film coatings, and (3) high surface area and porosity of the MWCNT sponge material for ion transport. The core/shell MWCNT/V(2)O(5) sponge delivers a stable high areal capacity of 816 μAh/cm(2) for 2 Li/V(2)O(5) (voltage range 4.0-2.1 V) at 1C rate (1.1 mA/cm(2)), 450 times that of a planar V(2)O(5) thin film cathode. At much higher current (50×), the areal capacity of 155 μAh/cm(2) provides a high power density of 21.7 mW/cm(2). The compressed sponge nanoarchitecture thus demonstrates exceptional robustness and energy-power characteristics for thin film cathode structures for electrochemical energy storage.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Absorption
  • Electric Power Supplies*
  • Electrodes*
  • Energy Transfer
  • Equipment Design
  • Equipment Failure Analysis
  • Ions
  • Lithium / chemistry*
  • Lithium / isolation & purification*
  • Nanotubes, Carbon / chemistry*
  • Nanotubes, Carbon / ultrastructure*
  • Porosity
  • Vanadium Compounds / chemistry*

Substances

  • Ions
  • Nanotubes, Carbon
  • Vanadium Compounds
  • Lithium
  • vanadium pentoxide