Tongchi Xia

Application of Na2CO3 Additive in Graphite Anode for Commercial Lithium-Ion Batteries

The electrochemical performances of the commercial liquid-state Al-plastic film lithium-ion batteries with Na 2 CO 3 in graphite electrode were studied by cycling performance, rate capability, internal resistance, low temperature performance, thermal stability, etc. It was found that the cycle performance of the batteries was successfully improved by pretreatment of graphite electrode with Na 2 CO 3 solution; especially for NalO, the capacity retention was more than 98% up to 400 cycles. However, the discharge capacity and rate capability decreased compared to the battery without Na 2 CO 3 , but not seriously.

Electrochemical properties of Bi-Ni and Bi-Ni-Mn composite-coated electrolytic manganese dioxide

The Bi-Ni and Bi-Ni-Mn composite is separately coated on the surface of commercial electrolytic manganese dioxide (EMD) by using a simple chemical precipitation/oxidation method. The results of X-ray diffraction show that a structure of γ-MnO2 is kept for all the coated EMD, but the intensity of their diffraction peaks is lower than uncoated one. Both the Bi0.5-Ni0.5 and Bi0.35-Ni0.35-Mn0.3 composite benefits the discharge capacity and high-power performance of the EMD electrodes. On the other hand, the results of scanning electron microscopy and energy dispersive spectroscopy confirm the more uniform distribution of the Bi0.15-Ni0.55-Mn0.3 composite on the surface of EMD than the Bi0.5-Ni0.5 one, thereby resulting in better cyclability of the electrodes. After 50 cycles at a 1C rate, the capacity retention rate of the Bi0.15-Ni0.55-Mn0.3 composite-coated electrode reaches to 80%, which is far larger than the un-coated (49%) and the Bi0.5-Ni0.5 composite-coated (63%) one.