Dry modification of electrode materials by roller vibration milling at room temperature

For the first time dry roller vibration milling at room temperature was used to prepare active carbon （AC） nano-particles and to modify MnO2 powder as electrode materials. In 30 min AC was milled to a mean particle size of 30-50 nm with increased crystallinity and higher specific surface area, predominantly mesoporous and with improved pore diameter distribution. Then, AC nano-particles were incorporated with MnO2 or bismuth-doped MnO2 nano-particles synthesized by sol-gel methods to prepare nano-composite electrode materials for studying their electrochemical performance. The AC nano-particles combined with 10 wt.% bismuth-doped MnO2 nano-particles were found to possess excellent electrochemical property with specific capacitance up to 308 F/g and without obvious attenuation with increasing current. Our method seems to ooen a new way to imorove AC based electrode materials used for clean energy such as suner capacitors.

Research on product size and grinding dynamics of vibration mills

In order to improve vibration mills grinding effect and increase productive efficiency, prime factors of vibration mills were gained much attention. The purpose of this study is to reveal product size distribution and grinding dynamics of vibration mills by orthogonal experi-ments. The metallurgical refractory materials were used as research object. In order to explore the relationships between grinding effect and primary factors, lots of milling experiments were carried out. Based on the results, the conclusions can be summarized： as time runs, the size distri-bution shows exponential trend, and range becomes more and more narrow. Also the quantitative analysis result between grinding effect and primary factors was obtained by non-linear regres-sion： high frequency, high amplitude and low fill ratio can increase grinding speed.