Lithium-Rich Anode Prelithiation via LixM Nanoparticles

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Lithium-ion batteries face significant first cycle capacity loss due to solid electrolyte interphase (SEI) formation and lithium trapping at the anodes, leading to low Coulombic efficiency, which is not effectively addressed by current methods such as excessive cathode material loading and prelithiation using lithium metal foil or stabilized lithium metal powder.

Innovation Solution

The development of LixM nanoparticles or microparticles, where M is a Group 14 element, incorporated into the anode to serve as a prelithiation reagent, forming a core-shell structure with a lithium compound matrix and a protective coating to enhance first cycle Coulombic efficiency by pre-storing lithium and preventing further oxidation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If lithium metal foil or stabilized lithium metal powder is used for prelithiation, then first cycle Coulombic efficiency is improved, but device complexity and manufacturing difficulty increase

Engineering Contradiction:

Improvefirst cycle Coulombic efficiencyVSAvoidprelithiation process complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent uses disposable lithium-rich cathode materials that are intentionally designed to be consumed during the first charge cycle to compensate for anode capacity loss. This eliminates the need for complex prelithiation processes while achieving the same effect of improving first cycle Coulombic efficiency.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

Solution Approach 2:

The patent incorporates lithium-rich cathode materials in advance that will automatically release lithium during the first charge cycle to pre-compensate for anode capacity loss. This preliminary action eliminates the need for separate prelithiation steps using lithium metal foil or powder.

Inventive Principle:

Principle #10Preliminary action

2Reliability

If excessive cathode material is loaded to compensate for first cycle capacity loss, then anode capacity loss is compensated, but battery specific energy and energy density are reduced

Engineering Contradiction:

Improvecapacity compensationVSAvoidbattery specific energy

Core Design Contradiction:

ReliabilityVSWeight of moving object

Solution Approach 1:

The patent changes the lithium content parameter of the cathode material to be excessively high (lithium-rich), allowing a small amount of cathode material to provide sufficient lithium for compensating anode capacity loss, thereby maintaining high specific energy while achieving capacity compensation.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent uses composite cathode materials combining lithium-rich compounds with conventional cathode materials, where the lithium-rich component provides excess lithium for capacity compensation while the conventional component maintains structural stability and electrochemical performance.

Inventive Principle:

Principle #40Composite materials

3Ease of manufacture

If lithium-rich cathode materials are used for prelithiation, then manufacturing scalability is improved, but particle size control and uniformity become more difficult

Engineering Contradiction:

Improvemanufacturing scalabilityVSAvoidparticle size uniformity

Core Design Contradiction:

Ease of manufactureVSManufacturing precision

Solution Approach 1:

The patent applies local quality control by ensuring that only specific regions of the cathode material particles contain excess lithium, while other regions maintain conventional composition. This allows for scalable manufacturing while maintaining sufficient particle uniformity for consistent performance.

Inventive Principle:

Principle #3Local quality

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 LixM nanoparticles improve the first cycle Coulombic efficiency of anodes to 80-100% by pre-storing lithium, reducing SEI formation, and maintaining capacity retention even in dry air and humid environments, thus enhancing the energy density and stability of lithium-ion batteries.

Implementation Method 1

LixM nanoparticles or microparticles, where M is a Group 14 element, incorporated into the anode to serve as a prelithiation reagent, forming a core-shell structure with a lithium compound matrix

Methodology Applied

Scientific EffectAlloying:

Implementation Method 2

forming a core-shell structure with a lithium compound matrix and a protective coating to enhance first cycle Coulombic efficiency by pre-storing lithium and preventing further oxidation

Methodology Applied

Scientific EffectOxidation prevention: Oxidation

Implementation Method 3

The LixM nanoparticles improve the first cycle Coulombic efficiency of anodes to 80-100% by pre-storing lithium, reducing SEI formation

Methodology Applied

Scientific EffectSEI formation reduction:

Data Source

PatentUS9966598B2High capacity prelithiation reagents and lithium-rich anode materials

Publication Date: 2018.05.08 THE BOARD OF TRUSTEES OF THE LELAND STANFORD JUNIOR UNIV

AI summary

Described here is a method for making an anode of a rechargeable battery, comprising incorporating a composition comprising LixM into the anode, wherein M is a Group 14 element. Also described here is an anode comprising a composition comprising LixM, wherein M is a Group 14 element, and a rechargeable battery comprising the anode.