Li-ion batteries: Phase transition

Hou Peiyu¹, Chu Geng², Gao Jian², Zhang Yantao¹, Zhang Lianqi^{1, †,}

Schematic illustration of the three host structures of Li_xCoO₂: O1 (a), O3 (b), and H1-3 (c). The vertices of the octahedra correspond to oxygen ions. Upper case letters describe the stacking of the close-packed oxygen layers. (d) Free energy curves as a function of Li concentration atT= 30°; regions separated by vertical dashed lines indicate the concentration intervals in which different host structures are stable.^[24]