Rapid discharge process of polythiophene cast film as cathode material

Electrochemical properties of cast films of a prototypical polythiophene, regioregular poly(3-hexylthiophene-2,5-diyl) (P3HT), were investigated in the lithium-ion battery (LIB) cell. The discharge curve shows both the oxidative high-V (~3.7V) and reductive low-V (~1.5V) plateaus. The observed capacities for both the plateaus are 60–80% of the ideal value (Qideal=162.45mAh/g) calculated based on the monomer unit. Significantly, the material shows very rapid discharge process up to ~1500C. The rapid discharge process was ascribed to the formation of electric double layer (EDL) like state, in which charged polymers are electrically neutralized by the approach of the Li+ (ClO4−) at the surface region of the polymer aggregates. Cast film of regioregular poly(3-hexylthiophene-2,5-diyl) (P3HT) shows very rapid discharge process up to ~1500C. The rapid discharge process was ascribed to the electric double layer (EDL) formation at the surface of the polymer aggregates. [Display omitted] •The cast films of regioregular poly(3-hexylthiophene-2,5-diyl) (P3HT) shows both the oxidative high-V (~ 3.7 V) and reductive low-V (~1.5 V) plateaus.•The observed capacities for both the plateaus are 60 – 80 % of the ideal value (Qideal = 162.45 mAh/g) calculated based on the monomer unit.•The material shows very rapid discharge process up to ~ 1500C probably due to the formation of electric double layer (EDL) like state at the surface region of the polymer aggregates.