Method for Preparing Positive Electrode Active Material for Lithium Secondary Battery, Positive Electrode Active Material for Lithium Secondary Battery, and Lithium Secondary Battery Including Same

Abstract

Disclosed are a method for preparing a positive electrode active material for a lithium secondary battery and a positive electrode active material for a lithium secondary battery, the method including: preparing a mixture of a precursor represented by Chemical Formula 1 below, a lithium composite oxide represented by Chemical Formula 2 below and capable of intercalating / deintercalating lithium ions, and a lithium feed material; and firing the prepared mixture:A(OH)2-a  [Chemical Formula 1]Li[LizA(1-z-a)Da]EbO2-b  [Chemical Formula 2]

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application claims priority to and the benefit of Korean Patent Application No. 10-2012-0025695, and PCT / KR2012 / 002286 filed in the Korean Intellectual Property Office on Mar. 13, 2012, and Mar. 28, 2012, the entire contents of which are incorporated herein by reference.BACKGROUND OF THE INVENTION[0002](a) Field of the Invention[0003]The present invention relates to a method for preparing a positive electrode active material for a lithium secondary battery, a positive electrode active material for a lithium secondary battery, and a lithium secondary battery including the same.[0004](b) Description of the Related Art[0005]Recently, with respect to the trend of miniaturization and lightweight of portable electronic devices, the batteries used as power for the devices need to be have high performance and high capacity.[0006]Batteries generate electric power by using materials capable of having an electrochemical reaction at positive and ...

AI Technical Summary

Benefits of technology

The present invention provides a positive electrode active material with high capacity, efficiency, and improved high-rate characteristics and long lifespan.

Problems solved by technology

However, these materials have a drawback in that the capacity is small.

However, LiCoO2 is not priced competitively since it is expensive and thus accounts for 30% or more of the battery price.

LiNiO2 is difficult to synthesize even though it provides the highest charge capacity in the above-mentioned positive electrode active materials.

Moreover, the self discharge of nickel is severe and reversibility of nickel is deteriorated.

Moreover, nickel insufficiently secures stability and thus is difficult to commercialize.

However, since the firing temperature needs to be varied depending on the compositional ratio of Ni / Co / Mn in order to exhibit the maximum performance for the compositions, the corresponding technology is restricted to a mixture of precursors having very similar compositions.

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