Electrochemical Performance of Aluminum Anodes with Different Grain Sizes for Al-Air Batteries
Yufeng Han, Jianming Ren, Chaopeng Fu, Min Jiang, Shusheng Lu, Jiao Zhang, Baode Sun
Abstract
Aluminum-air batteries with high energy density and low cost are regarded as a promising candidate for green power delivery in transportation and uninterrupted energy supply. In this study, Al anodes with various grain sizes (108–537 μ m) are prepared by adding Al–Ti–B refiner with different compositions during the casting process. The grain size can be well manipulated, and the approach is simple without using any mechanical processing. The grain size of the Al anodes are well-characterized and evaluated, and the electrochemical performances of the Al samples with different grain sizes are investigated as anodes for Al-air batteries by various electrochemical techniques. The results show that grain size significantly affect the battery performance. With the decrease in grain size of the Al anode, the corresponding Al-air battery displays higher working voltage and larger specific capacity, resulting in the increase by 105% of energy density, which is explained by the increased grain boundary and more uniform microstructure. This study demonstrates a new and economic way to boost the performance of Al-air batteries.