Influences of polyethylene glycol (PEG) on the performance of LiMn2O4 cathode material for lithium ion battery

Abstract

Spinel phase LiMn2O4 is synthesized by a polyethylene glycol (PEG)-assisted co-precipitation method. The samples are characterized by X-ray diffraction and scanning electron microscopy techniques. The LiMn2O4 samples synthesized have similar morphology and uniform size of about 150–350 nm. The electrochemical measurements show that as-prepared LiMn2O4 nanoparticle sample using PEG with the molecular weight as 4000 (PEG-4000) shows the best cycling performance and highest rate capability among all samples, its initial discharge capacity is 133 mAhg−1 and maintains at 122 mAhg−1 under 0.5 °C after 50 cycles. The loss of its capacity was just 5.1 %. To control the particle size of LiMn2O4 is one of important factors for its application as a cathode material.