This may be due to the increase in the number of free mobile ions [11]. These free mobile ions
also increase the amorphous structure of the polymer through the favorable free volume and therefore
the ion migration takes place easily. However, when more lithium salt was added, the conductivity
decreases upon further additon of the amount of doping salt due to formation of neutral ion pairs [12]
thus reducing the number density of mobile ions and hence the conductivity.