High-Nickel Cathode Material Structure to Suppress Cation Disorder

Solution Overview

Problem

Conventional high-nickel lithium oxide cathode active materials suffer from cation disorder and reduced structural stability, leading to degraded life-span and performance in lithium secondary batteries.

Innovation Solution

A cathode active material comprising lithium-nickel composite metal oxide particles with a specific composition, including transition metals and additional elements, forms a secondary particle structure with metal sulfate, carbonate, or oxide components acting as binders between primary particles, thereby suppressing cation disorder and enhancing structural stability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If high-nickel lithium oxide is used as cathode active material to increase battery capacity, then energy density and charging rate are improved, but cation disorder occurs and structural stability deteriorates

Engineering Contradiction:

Improveenergy densityVSAvoidstructural stability

Core Design Contradiction:

Use of energy by moving objectVSStability of the object's composition

Solution Approach 1:

The patent applies local quality by creating a core-shell structure where the inner core contains high-nickel lithium oxide for high capacity, while the outer shell contains protective coating layers (such as aluminum oxide, aluminum hydroxide, or lithium phosphate) that provide structural stability and prevent cation disorder. This allows different regions of the material to have different functions - the core provides energy density while the shell provides structural protection.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent uses composite materials by combining high-nickel lithium oxide with protective coating materials to form a composite cathode active material. The composite structure integrates the high capacity advantage of high-nickel lithium oxide with the structural stability advantage of the protective coating materials, resolving the contradiction between energy density and structural stability.

Inventive Principle:

Principle #40Composite materials

2Quantity of substance

If high-nickel lithium oxide is used to increase battery capacity, then initial capacity is improved, but life-span and discharge capacity retention deteriorate due to cation disorder

Engineering Contradiction:

Improveinitial capacityVSAvoidlife-span

Core Design Contradiction:

Quantity of substanceVSDuration of action of stationary object

Solution Approach 1:

The patent applies local quality by creating a core-shell structure where the inner core contains high-nickel lithium oxide for high capacity, while the outer shell contains protective coating layers (such as aluminum oxide, aluminum hydroxide, or lithium phosphate) that provide structural stability and prevent cation disorder. This allows different regions of the material to have different functions - the core provides energy density while the shell provides structural protection.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent applies beforehand cushioning by pre-coating the high-nickel lithium oxide particles with protective materials before battery assembly. This protective layer acts as a cushion that prevents cation disorder and structural degradation during battery cycling, thereby extending life-span while maintaining high initial capacity.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

3Speed

If nickel content is increased to improve battery performance, then charging rate is improved, but structural stability and electrical property deteriorate

Engineering Contradiction:

Improvecharging rateVSAvoidelectrical property

Core Design Contradiction:

SpeedVSReliability

Solution Approach 1:

The patent uses composite materials by combining high-nickel lithium oxide with protective coating materials to form a composite cathode active material. The composite structure integrates the high charging rate advantage of high-nickel lithium oxide with the structural stability advantage of the protective coating materials, resolving the contradiction between charging rate and electrical property reliability.

Inventive Principle:

Principle #40Composite materials

Data Source

PatentUS12401031B2Cathode active material for lithium secondary battery and lithium secondary battery including the same

Publication Date: 2025.08.26 SK ON CO LTD

AI summary

A cathode active material for a lithium secondary battery according to embodiments of the present invention has a high-nickel composition and includes a lithium-nickel composite metal oxide particle in which lithium, nickel and a metal having an oxidation number of +2 are combined in a predetermined range. A cation disorder caused when a nickel ion is present at a lithium-ion site is reduced to improve structural stability of the cathode active material. An initial capacity and a battery efficiency of a lithium secondary battery can be improved using the cathode active material.