LiFePO4, LiCo0.25Fe0.75PO4 and LiCo0.1Mn0.1Fe0.8PO4 phosphoolivines were characterized in terms of their structural and electrochemical properties. Detailed analysis of transport and electrochemical properties was conducted using electrical conductivity, Seebeck coefficient and Li/Li+/LixFe1 - y - zMnyCozPO4 cell open circuit voltage (OCV) measurements. In-situ XRD studies were employed in order to elucidate Li extraction/insertion mechanism in the studied systems. Correlation between the observed structural modification ongoing during the electrochemical reaction and physicochemical properties of the studied phosphoolivines has been proposed. (C) 2016 Elsevier B.V. All rights reserved.