Nickel-Rich Cathode Strain Control for Longer-Life Lithium Batteries

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing lithium secondary batteries face challenges in achieving improved capacity characteristics and lifespan characteristics, particularly due to the limitations of lithium-nickel-based metal oxide particles with high nickel content, which can lead to decreased long-term storage stability and increased side reactions with electrolytes.

Innovation Solution

The lithium secondary battery incorporates lithium-nickel-based metal oxide particles with a controlled crystallite strain of 0.2 to 0.4, calculated using the Williamson-Hall method, and a composition that balances high nickel content with manganese and reduced cobalt, enhancing electrochemical activation and stability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If high nickel content is increased in lithium-nickel-based metal oxide to implement high energy density, then energy density is improved, but long-term storage stability deteriorates and side reactions with electrolytes increase

Engineering Contradiction:

Improveenergy densityVSAvoidlong-term storage stability

Core Design Contradiction:

Use of energy by moving objectVSReliability

Solution Approach 1:

The patent applies parameter changes by precisely controlling the crystallite strain parameter (ε) within 0.2 to 0.4 and crystallite size within 1 nm to 10 nm. These parameter optimizations enable the cathode active material to achieve high energy density while maintaining long-term storage stability, resolving the contradiction between energy density and reliability.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent uses composite materials by combining lithium-nickel-based metal oxide with specific crystallite characteristics (strain 0.2-0.4, size 1-10 nm) to create a cathode active material that balances high nickel content for energy density with controlled structural properties for stability, thereby resolving the contradiction between energy density and long-term storage stability.

Inventive Principle:

Principle #40Composite materials

2Use of energy by moving object

If high nickel content is increased in lithium-nickel-based metal oxide to implement high energy density, then energy density is improved, but side reactions with electrolytes increase

Engineering Contradiction:

Improveenergy densityVSAvoidside reactions with electrolytes

Core Design Contradiction:

Use of energy by moving objectVSObject-generated harmful factors

Solution Approach 1:

The patent applies parameter changes by controlling crystallite strain (0.2-0.4) and crystallite size (1-10 nm) to reduce side reactions with electrolytes while maintaining high nickel content for energy density. The optimized crystallite parameters create a more stable structure that minimizes harmful interactions with the electrolyte.

Inventive Principle:

Principle #35Parameter changes

3Productivity

If crystallite strain is controlled within 0.2 to 0.4 and crystallite size within 1 nm to 10 nm, then capacity characteristics and lifespan characteristics are improved, but manufacturing precision requirements increase

Engineering Contradiction:

Improvecapacity characteristics and lifespan characteristicsVSAvoidcrystallite strain and size control precision

Core Design Contradiction:

ProductivityVSManufacturing precision

Solution Approach 1:

The patent defines specific parameter ranges (crystallite strain 0.2-0.4, crystallite size 1-10 nm) that balance performance improvement with manufacturing feasibility. These parameter specifications provide clear targets for manufacturing while ensuring improved capacity and lifespan characteristics.

Inventive Principle:

Principle #35Parameter changes

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

This approach improves the capacity and lifespan characteristics of the lithium secondary battery by maintaining electrical conductivity and reducing structural deterioration, while allowing for high energy density and efficiency.

Implementation Method 1

The lithium secondary battery may store an electric energy by a difference in chemical potential when lithium ions are intercalated and deintercalated between the cathode and the anode

Methodology Applied

Scientific EffectIntercalation: Absorption (physical)

Implementation Method 2

peaks of (101) plane, (102) plane, (104) plane, (105) plane and (107) plane of the lithium-nickel-based metal oxide particles measured through XRD analysis

Methodology Applied

Scientific EffectX-ray diffraction: X-Ray

Implementation Method 3

calculated by applying the Williamson-Hall method defined by Equation 1 below to peaks of (101) plane, (102) plane, (104) plane, (105) plane and (107) plane

Methodology Applied

Scientific EffectWilliamson-Hall method:

Data Source

PatentUS20250286056A1Lithium secondary battery

Publication Date: 2025.09.11 SK ON CO LTD

AI summary

A lithium secondary battery according to the embodiments of the present disclosure includes: a cathode which includes a cathode active material layer including a cathode active material containing lithium-nickel-based metal oxide particles; and an anode disposed to face the cathode, wherein the lithium-nickel-based metal oxide particles have a crystallite strain (ε) of 0.2 to 0.4, which is calculated by applying the Williamson-Hall method defined a predetermined equation to peaks of (101) plane, (102) plane, (104) plane, (105) plane and (107) plane of the lithium-nickel-based metal oxide particles measured through XRD analysis on the cathode active material layer. Accordingly, capacity characteristics and lifespan characteristics of the lithium secondary battery are improved.