Materials of Tin-Based Negative Electrode of Lithium-Ion Battery

Among high-capacity materials for the negative electrode of a lithium-ion battery, Sn stands out due to a high theoretical specific capacity of 994 mA h/g and the presence of a low-potential discharge plateau. However, a significant increase in volume during the intercalation of lithium into tin leads to degradation and a serious decrease in capacity. An efficient method to overcome this drawback is to create composites with nickel or carbon to prevent the occurrence of microstresses. Powders of Sn–Ni samples were produced by the reduction of metals in the liquid phase and analyzed by X-ray powder diffraction analysis. A Sn/carbon nanotubes powder was obtained by heat treatment in a vacuum and studied by scanning electron microscopy. The electrochemical properties of the material were investigated by chronopotentiometry in a three-electrode electrochemical cell. The Sn/carbon nanotube composite material has a much higher capacity than tin nanopowders when cycling at a current density of ~0.1 A/g. It follows from this that the former has better electrochemical properties and can be used as a negative electrode material.