Impact of Binder Choice on the Performance of α-Fe[sub 2]O[sub 3] as a Negative Electrode

Abstract
The electrochemical performance of negative electrodes based on commercially available micrometer-sized α-Fe2O3α-Fe2O3 powder and four different binders was investigated. α-Fe2O3α-Fe2O3 electrodes made using sodium carboxymethyl cellulose binder and two proprietary binders show better cycling performance than electrodes made from the conventional binder, polyvinylidene fluoride (PVDF). Heat-treating the PVDF electrodes to 300°C300°C improves electrode performance dramatically. A specific capacity of over 800mAh∕g800mAh∕g for over 100cycles100cycles has been achieved for Li∕α-Fe2O3Li∕α-Fe2O3 cells with micrometer-sized α-Fe2O3α-Fe2O3 , by contrast to many teachings in the literature where it is claimed nanometer sized particles are required to obtain such performance. As is the case for composite electrodes made from powders of metal alloys, we suggest that binder choice has a great impact on the performance of metal oxide electrodes demonstrating large volume expansion during lithiation, such as α-Fe2O3α-Fe2O3 .