Research On High Rate Lithium-ion Batteries For Electromagnetic Launcher

Electromagnetic Launch (EML) needs great energy instantly when works. The power grid is difficult to supply the energy, so a large quantity of batteries are used to store energy and magnify power for the EML system. Because safety must be taken into consideration firstly, the lithium iron phosphate based lithium-ion batteries (LIBs) are employed. In order to miniaturize the battery system, LIBs with high power densities are studied. The internal DC resistance of a battery, which is directly and closely related with the power density, includes the ohm resistance and the polarization resistance. On the one hand, to reduce the ohmic resistance, the structure of the battery is optimized, such as the adoption of full lugs and carbon coated collector. On the other hand, to reduce the polarization resistance, the battery material is optimized, such as the adoption of nanomaterial and optimization of surface density. The energy density of the battery reaches 90wh/kg under 40C discharge rate. Moreover, the results of simulation and experiment show good performance of the battery.