Thin Nanocolumnar Ge0.9Se0.1 Films Are Rapidly Lithiated/Delithiated

Thin films of amorphous nanocolumnar germanium subselenide Ge0.9Se0.1, with a lithiation/delithiation capacity of 1.2 Ahr g(-1), retain a capacity of 0.8 Ahr g(-1) when lithiated in 1.2 min and 0.5 Ahr g(-1) when lithiated in 36 s. After 1000 cycles of 72 s lithiation/72 s delithiation, the films retain a capacity of 0.8 Ahr g(-1). For delithiation in 3.3 s, the capacity is 0.9 Ahr g(-1), and the specific delithiation current is 1.34 kA g(-1) (kiloampere per gram).