Functionalised polyterthiophenes as anode materials in polymer/polymer batteries

A functionalised polyterthiophene, poly(3′-styryl-4,4″-didecyloxyterthiophene) (poly(OC10DASTT)), was investigated as an anode coupled with a polypyrrole cathode in a battery with a lithium hexafluorophosphate (LiPF6) in 1:1 ethylene carbonate (EC):dimethylcarbonate (DMC) electrolyte. The polymer was electrodeposited on stainless steel mesh and Ni/Cu-coated nonwoven polyester fabric. A discharge capacity of 45.2 mAh/g was obtained for the battery constructed using poly(OC10DASTT) on a Ni/Cu-coated fabric as the anode. An alternative anode material, poly(4,4″-didecyloxyterthiophene) (poly(OC10STT)) was electropolymerised on Ni/Cu-coated fabric, and exhibited a maximum discharge capacity of 94.7 mAh/g. The capacity decreased for both polymers with repeated charge/discharge cycling. This deterioration is attributed to mechanical degradation of the polymer as evidenced by scanning electron microscopy (SEM).