High-Nickel Cathode Coating to Prevent Particle Cracking

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing lithium nickel cobalt manganese oxide positive electrode active materials face issues with particle breakage and cracking during electrode preparation and charge/discharge cycles, leading to increased degradation and reduced life characteristics, especially with high nickel content, which affects the stability and durability of lithium secondary batteries.

Innovation Solution

A method involving sequential cobalt and boron coating of lithium composite transition metal oxide particles, forming a cobalt coating layer followed by a boron coating layer, to stabilize the structure and enhance particle strength and durability, while maintaining a high nickel content.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If the nickel content in the positive electrode active material is increased to improve initial capacity characteristics, then the initial capacity improves, but particle breakage and cracking occur during electrode preparation and charge/discharge, leading to degraded life characteristics

Engineering Contradiction:

Improvenickel contentVSAvoidlife characteristics

Core Design Contradiction:

Quantity of substanceVSReliability

Solution Approach 1:

The patent applies local quality by forming a cobalt-containing coating layer specifically on the surface of the lithium composite transition metal oxide particles. This creates a localized region with different properties (higher cobalt content, enhanced structural stability) at the particle surface, while the bulk material maintains its high nickel content for high capacity. The coating layer acts as a protective shell that locally addresses the structural instability issue without compromising the overall high-nickel composition.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent employs composite materials by creating a core-shell structure where the core is high-nickel lithium composite transition metal oxide and the shell is a cobalt-containing coating layer. This composite structure combines the high capacity advantage of high-nickel materials with the structural stability advantage of cobalt-containing materials, effectively resolving the contradiction between initial capacity and life characteristics.

Inventive Principle:

Principle #40Composite materials

2Ease of manufacture

If conventional lithium nickel cobalt manganese oxide is used in the form of aggregated secondary particles, then the manufacturing process is simpler, but particle breakage occurs during rolling and cracks form during charge/discharge, increasing degradation and gas generation

Engineering Contradiction:

Improvemanufacturing process simplicityVSAvoidparticle strength

Core Design Contradiction:

Ease of manufactureVSStrength

Solution Approach 1:

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent applies preliminary action by forming the cobalt-containing coating layer on the particle surface before the electrode manufacturing process. This pre-protection measure prevents particle breakage during subsequent rolling and handling operations, and also prevents crack formation during charge/discharge cycles. The coating is applied in advance to mitigate future degradation issues.

Inventive Principle:

Principle #10Preliminary action

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The coated particles exhibit improved structural stability, higher initial capacity, and reduced resistance, resulting in lithium secondary batteries with enhanced capacity retention and lower resistance increase rates.

Implementation Method 1

mixing a lithium composite transition metal oxide in a form of a single particle or pseudo-single particle with a cobalt-containing raw material and performing a heat treatment to form a cobalt coating layer on a surface of the lithium composite transition metal oxide

Methodology Applied

Scientific EffectHeat treatment: Heat Treatment

Implementation Method 2

mixing the lithium composite transition metal oxide having the cobalt coating layer formed thereon with a boron-containing raw material and performing a heat treatment to form a boron coating layer on the cobalt coating layer

Methodology Applied

Scientific EffectHeat treatment: Heat Treatment

Data Source

PatentEP4325600B1Method for manufacturing cathode active material for lithium secondary battery, and cathode active material manufactured thereby

Publication Date: 2026.01.14 LG ENERGY SOLUTION LTD

Figure 1~2
Figure 3

AI summary

The present invention relates to a method for manufacturing a cathode active material for a lithium secondary battery and a cathode active material for a lithium secondary battery manufactured thereby, the method comprising the steps of: (1) mixing a single-particle or quasi-single-particle lithium composite transition metal oxide with a cobalt-containing raw material and heat-treating the mixture to form a cobalt coating layer on the surface of the lithium composite transition metal oxide; and (2) mixing the lithium composite transition metal oxide having the cobalt coating layer formed thereon with a boron-containing raw material and heat-treating the mixture to form a boron coating layer on the cobalt coating layer.