Developments / New technologies

ENERGY AND ECO-EFFICIENT MECHANOCHEMICAL SYNTHESIS OF NANO-LiFePO4/С FOR LITHIUM-ION BATTERIES

Energy density of LiFePO₄ vs.
well-known cathode materials

Energy and eco-efficient mechanochemical method of synthesis of nanocomposite cathode material LiFePO₄/С with grain size ~ 50 nm has been developed in the Institute of Solid State Chemistry and Mechanochemistry of Siberian Branch of Russian Academy of Sciences.

Cathode material LiFePO₄/C is characterized by high discharge voltage (3.4 V vs. Li/Li+), the presence of plateau on charge-discharge curves and a high theoretical capacity (170 mA∙h/g), which can be achieved in practice.

LiFePO₄ is low-cost, nontoxic, structurally and chemically stable when charging at increased temperatures; its electrochemical features are comparable with those of well-known cathode materials.

Nanocomposite prepared by mechanical activation (MA) - the grains of LiFePO₄, surface-modified by crystalline carbon embedded into the matrix of amorphous carbon – overcomes the main disadvantage of LiFePO₄ – low electronic conductivity (10^-9 S/cm) and ensures high-rate capability and high discharge capacity 150-160 mA∙h/g, close to the theoretical one.

Method of synthesis LiFePO₄/С:

Characteristics of mechanonanocomposite LiFePO₄/С:

The advantages of the method:

• preparation of fine LiFePO4 particles;
• formation of uniform nano-sized conducting carbon coating;
• combination of the synthesis and the coating stages;
• low time and energy inputs;
• echo-efficiency (the absence of wastes (opposite to solution methods)

LiFePO₄ is a promising material to be used in hybrid and electro-vehicles, where the cost and safety are of great importance.