Preparations And Battery Performances Of Ba-Fe(â…¥)-based Cathode Materials

In this paper, recent development of ferrates and the history of batteries were summarized. It indicates that the super-iron batteries have a huge potential. The investigations focus on physical chemical methods of improving the stability and discharge performance of super-iron battery with cathode of barium ferrate. The paper adopted a new method to prepare high purity ferrate salts (potassium ferrate and barium ferrate), and determined the optimizational parameters such as solvent, temperature, time,etc.. Some modified additives can greatly improve the stability and discharge performance of barium ferrate batteries. The chromite method was used to determine the purity of ferrate salts.The structure of ferrates was characterized by XRD and FTIR. The additives in barium ferrate materials were analyzed by AAS. The experimental results show that (1) the addition of silica can greatly improve its stability in the process of synthesizing baruim ferrate, and when the content of silica in the BaFeO4 was 0.48%, its purity was only reduced by 12.9% after 60 days in room temperature. (2)discharge performance of the super-iron battery with barium ferrate was obviously improved if mixed with manganese compound, silica and chloride in the synthesis, yielding over 4.80%,3.57%and 6.15% higher capacity than batteries without the addition, and manganese compound and silica as additives was found to has a cooperating action.(3) Ba-Fe(â…¥) composite materials had outstanding specific capacity and discharge efficiency, and after complexed with chloride, its specific capacity was 286mAh/g, and its discharge efficiency was 90.5%.(4) the super-iron battery with expanded graphite as a conductor had higher discharge performance than one with normal graphite, so, its discharge time was prolonged 8.3%, and its discharge capacity and energy was increased 14.5%and 15.5% respectively. The paper exhibits that the alkaline super-iron battery with cathode of barium ferrate has many advantages such as high capacity, low cost, no pollution, etc. The results greatly promote the development of industrial production of ferrate materials and super-iron batteries.