Electrochemical studies of novel olivine-layered (LiFePO4-Li2MnO3) dual composite as an alternative cathode material for lithium-ion batteries

• Published in: Journal of solid state electrochemistry 2018-08, Vol.22 (8), p.2507-2513
• Main Authors: Saroha, Rakesh, Panwar, Amrish K., Gaur, Anurag, Sharma, Yogesh, Kumar, Vinay, Tyagi, Pawan K.
• Format: Article
• Language: English
• Subjects: Analytical Chemistry; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Composite materials; Composition; Condensed Matter Physics; Diffraction; Diffraction patterns; Discharge; Electrochemistry; Electrode materials; Energy Storage; Laminates; Lithium; Lithium-ion batteries; Manganese dioxide; Morphology; Multilayers; Olivine; Original Paper; Physical Chemistry; Rechargeable batteries; X-ray diffraction
• ISSN: 1432-8488; 1433-0768
• DOI: 10.1007/s10008-018-3963-6

In the present work, olivine-layered composites, i.e., LiFePO 4 -Li 2 MnO 3 , are successfully synthesized in the form of a single monolithic electrode and layer arrangement . X-ray diffraction (XRD) patterns revealed that the prepared compositions exhibit the peaks correspond to the layered m- Li 2 MnO 3 ( C2/m space group) and orthorhombic LiFePO 4 with Pnma space group. Microstructural investigations indicate that all the samples possess nearly same morphology with a combination of smaller as well as bigger grains. CV results demonstrate that all the prepared samples possess anodic peak around 3.6 and 4.7 V along with a broad cathodic peak around 3.2 V which is due to intercalation of Li-ion at 16c octahedral sites of the spinel structure formed by MnO 2 . Among all the compositions, layer arrangement of LiFePO 4 and Li 2 MnO 3 , i.e. LFP/LMO layered arrangement, shows the best cycling and rate performances. LFP/LMO exhibits a discharge capacity of 178 ± 5 mA h/g at a current density 10 mA/g and holds 98% of the capacity up to 100 charge/discharge cycles measured at 20 mA/g.