X. Sun et al.
(a)
(b)
Fig. 7. The galvanostatic charge – discharge curves at 40 mA/g of AMP (a) and CMP (b).
(a)
(b)
Fig. 8. Cycle performance of AMP and CMP at current density of 40 mA/g (a), rate capability performance of CMP at di®erent current densities (b).
loss appeared at current density of 200 mA/g and 400 mA/g. When the current density of 800 mA/g was applied, the speci¯c capacity decreased to around 200 mAh/g, which is close to the capacity of the AMP battery at 40 mA/g. When reducing the current density, the speci¯c capacity easily recovered. The CMP electrode exhibited good cycle performance and high current impulse withstand- ing capability. The result also indicated a high Coulomb e±ciency of nearly 100% at all current rates in Fig. 8(b). 4. Conclusion MWCNT paper was made up of 50 wt.% MWCNTs and 50% cellulose. It showed the property of light- weight, °exibility and good conductivity. The MWCNT paper can be manufactured easily by
process to mitigate the adverse impact of applying MWCNTs as anode material. Figure 8(a) shows the galvanostatic discharge speci¯c capacity versus the cycle number for the battery made from the AMP and CMP electrodes. The speci¯c capacity was greatly improved by adopting the CMP as negative electrode. Due to the fact that the electrode structure was improved by turning the cellulose to amorphous carbon, the re- sistivity of electrode was greatly decreased from 0 : 651 cm to 0 : 150 cm with carbonization treatment. After 50 cycles, the CMP battery still maintained a high speci¯c capacity of around 500 mAh/g. The electrochemical cycling behavior of the CMP battery at di®erent current densities from 40 mA/g to 800 mA/g is shown in Fig. 8(b). A dis- charge speci¯c capacity of around 500 mAh/g is obtained at 40 mA/g after 30 cycles. And a slight
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