 Olivine based cathodes with a chemical formula of LiMn1−xMxPO4 (where M = Fe, Ni, Co…) are considered as a potential candidate with their viability of high voltage applications, improved stability against various battery components and ambient conditions. However, the technology for scaling up the material synthesis remains a challenge. Solution combustion method stood forward among the other synthesis methods since it is possible to synthesize large quantities of materials with improved homogeneity and repeatability. In this study, olivine based LiMn1−xCoxPO4@C cathode materials were synthesized by a modified solution combustion method (SC) using glycine as fuel source, and starch as an additional carbon source. X-ray diffraction characterization of all samples suggested a highly crystallized orthorhombic olivine structure. In addition, it confirmed that Co2+ substitutes proportionately the transition metal Mn2+ without structural changes. Electron microscopy and Raman results pointed out the nanometer sized particles with a limited agglomeration and very thin carbon coating was successfully done. Electrochemical results suggested that Co-doping can improves cycling and high-rate capability of the pristine LiMnPO4/C material. Among all doped samples, LiMn0.99Co0.01PO4/C exhibited the best rate capability and cycling stability and the highest initial discharge capacity of 157 mAhg−1 at C/20, with a remarkable coulombic efficiency of about 98.1%, which is higher compared to that of the pristine sample LiMnPO4/C (80.38%). As a potential impact; this work reveals structure–property-process relationships for developing high-voltage cathodes by SC method targeted the best performance.