Preparation and Performance of 100Ah Li-ion Battery with LiFePO4 as Cathode Material

摘要

The 100Ah Li-ion battery with LiFePO_4 material as cathod materails is fabricated by laminated electrode technique. The key preparation techniques of preparating battery is optimized in this paper.The examinations results indicate that it is an effective method to improve electric performance of battery by VGCF addition in the cathode activated materials; Solid phase mixing technique can obviously improve the electrode coating effect and reduce the electrode polarization effect.When the catthod electrode surface density is kept as 2.4 g.dm~(2-), and pressing density is kept as 2.6 g/cm~(3-), the largest capacity of the battery is105.56 Ah at the 0.5C discharge current, and the specific capacity of cathod LiFePO_4 materials is 135.84mAh/g; There is above 98% capacity retention rate of LiFePO_4 battery after 200 cycles at 0.5C discharge current. After the safety examinations including overfilling, short circuit, extrusion and needle-punching, prepared LiFePO_4 battery shows its desirable safty performance.