Composite Cathode Active Material Shell for Nickel Leakage Suppression

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Nickel-based cathode active materials in lithium batteries suffer from poor lifetime characteristics and thermal stability due to high residual lithium and side reactions, leading to battery performance deterioration.

Innovation Solution

A composite cathode active material is developed, comprising a core of lithium nickel transition metal oxide with a shell of distinct first and second metal compositions, which suppresses nickel ion leakage and side reactions through a multi-layered or single-layered structure, improving thermal and structural stability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If nickel-based cathode active material is used to achieve high capacity, then battery capacity is improved, but lifetime characteristics and thermal stability deteriorate due to residual lithium and side reactions

Engineering Contradiction:

Improvebattery capacityVSAvoidlifetime characteristics

Core Design Contradiction:

Quantity of substanceVSReliability

Solution Approach 1:

A shell layer comprising a spinel structure and a layered structure is introduced as an intermediary between the nickel-based cathode active material and the electrolyte. This shell layer mediates the interaction by suppressing side reactions and nickel ion leakage while maintaining lithium ion conductivity, thereby improving lifetime characteristics without sacrificing high capacity

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The cathode active material is designed as a composite structure combining a nickel-based layered oxide core with a shell layer containing both spinel and layered structures. This composite structure leverages the high capacity of nickel-based materials while the shell provides enhanced stability and suppressed side reactions, resolving the contradiction between capacity and reliability

Inventive Principle:

Principle #40Composite materials

2Quantity of substance

If nickel-based cathode active material is used to achieve high capacity, then battery capacity is improved, but thermal stability deteriorates due to side reactions

Engineering Contradiction:

Improvebattery capacityVSAvoidthermal stability

Core Design Contradiction:

Quantity of substanceVSTemperature

Solution Approach 1:

The shell layer acts as a thermal barrier and chemical intermediary that suppresses exothermic side reactions between the nickel-based cathode material and the electrolyte. The spinel and layered structures in the shell provide thermal stability while maintaining ionic conductivity, preventing thermal runaway at elevated temperatures

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The shell layer creates a chemically inert environment around the nickel-based cathode active material, isolating it from the electrolyte and preventing harmful side reactions that would compromise thermal stability. This inert barrier allows the high-capacity nickel-based material to operate safely at elevated temperatures

Inventive Principle:

Principle #39Inert atmosphere (Inert environment)

3Reliability

If shell layer is added to suppress nickel ion leakage and side reactions, then thermal stability and lifetime characteristics are improved, but device complexity increases

Engineering Contradiction:

Improvethermal stabilityVSAvoidstructure complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

Multiple functional structures (spinel phase and layered phase) are merged into a single integrated shell layer that simultaneously provides nickel ion leakage suppression, side reaction prevention, and lithium ion conductivity. This merging approach achieves multiple protective functions without proportionally increasing structural complexity

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The shell layer is designed with multi-functionality, serving as both a protective barrier against nickel ion leakage and side reactions, while also maintaining lithium ion conductivity and providing structural stability. This universal design resolves the contradiction by achieving multiple benefits within a single structural component

Inventive Principle:

Principle #6Universality (Multi-functionality)

Data Source

PatentUS20240258517A1Composite cathode active material, cathode and lithium battery each containing composite cathode active material, and method of preparing composite cathode active material

Publication Date: 2024.08.01 SAMSUNG ELECTRONICS CO LTD

AI summary

A composite cathode active material, a cathode and a lithium battery each including the composite cathode active material, and a method of manufacturing the composite cathode active material. The composite cathode active material includes a core including a plurality of primary particles, and a shell disposed on the core, wherein a primary particle of the plurality of primary particles includes a lithium nickel transition metal oxide, the shell includes a first composition and a second composition, wherein the first composition contains a first metal and the second composition contains a second metal, wherein the first metal includes a metal of Groups 2, 4, 5, and 7 to 15, the second metal includes a metal of Group 3, and the first composition includes a first phase and the second composition includes a second phase that is distinguishable from the first phase.