A copolymer that exhibits a positive temperature coefficient (PTC) effect and an oxidation potential which are controlled according to objectives. Such a conductive copolymer cannot affect or can rather improve, in a normal state, performance and operation...

Provided are: an additive for position electrodes, which is capable of increasing the output of a lithium secondary battery and is capable of maintaining cycle characteristics even during high-speed charge and discharge and a positive electrode for lithium...