Passivated Pre-lithiated Group IVA Particles for Battery Anodes

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current methods for pre-lithiation of anode materials in lithium-ion batteries are not commercially viable due to high irreversible capacity loss and volume expansion issues, which lead to rapid capacity fade and limited integration with existing manufacturing processes.

Innovation Solution

Application of surface modifiers to Group IVA particles (such as Si, Ge, or Sn) to create an artificial Solid Electrolyte Interphase (SEI) barrier, allowing these particles to be dispersed in aqueous-based slurries and reducing volume expansion, thereby enhancing cycle stability and charge capacity retention.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If pre-lithiation of anode materials is performed using conventional methods, then charge capacity is improved, but irreversible capacity loss increases and cycle stability deteriorates

Engineering Contradiction:

Improvecharge capacityVSAvoidirreversible capacity loss

Core Design Contradiction:

Quantity of substanceVSLoss of energy

Solution Approach 1:

The patent applies preliminary action by pre-forming a stable SEI layer on the anode materials before battery assembly. This is achieved by treating the anode with a solution containing lithium salt and cyclic carbonate before electrode fabrication, allowing the SEI to form in a controlled manner prior to cycling, thereby reducing subsequent irreversible capacity loss

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent uses an intermediary substance (cyclic carbonate solution containing lithium salt) as a mediator to facilitate controlled SEI formation. This intermediary enables gradual lithium insertion and stable interface formation without the harsh conditions that cause excessive irreversible capacity loss in conventional pre-lithiation methods

Inventive Principle:

Principle #24Intermediary (Mediator)

2Quantity of substance

If Group IVA particles are used to increase charge capacity, then energy storage is improved, but volume expansion causes mechanical stress and particle pulverization

Engineering Contradiction:

Improvecharge capacityVSAvoidparticle structural integrity

Core Design Contradiction:

Quantity of substanceVSStrength

Solution Approach 1:

The patent applies flexible shells by coating Group IVA particles with a thin film of carbon or other protective materials. This shell structure accommodates the volume expansion of the core particles during lithiation while maintaining structural integrity, preventing particle pulverization and preserving electrical contact throughout cycling

Inventive Principle:

Principle #30Flexible shells and thin films

Solution Approach 2:

The patent uses composite materials by combining Group IVA particles with carbon coatings or matrix materials. This composite structure integrates the high capacity benefits of Group IVA materials with the structural stability of carbon, creating a synergistic system that withstands volume expansion stresses

Inventive Principle:

Principle #40Composite materials

3Productivity

If pre-lithiation is performed before electrode laminate formation, then manufacturing efficiency is improved, but reactions with aqueous slurries cause lithium loss

Engineering Contradiction:

Improvemanufacturing efficiencyVSAvoidlithium loss

Core Design Contradiction:

ProductivityVSLoss of substance

Solution Approach 1:

The patent applies inert atmosphere by conducting the pre-lithiation treatment in an atmosphere controlled to exclude moisture and oxygen, or by using moisture-resistant cyclic carbonate solvents. This protects the reactive pre-lithiated materials from unwanted reactions with aqueous components during subsequent electrode fabrication steps

Inventive Principle:

Principle #39Inert atmosphere (Inert environment)

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 solution results in high first-cycle efficiency and subsequent cycle efficiencies, mitigating irreversible capacity loss and reducing the severity of volume expansion, enabling seamless integration into existing industry processes.

Implementation Method 1

surface modifiers applied to passivate lithium from reactions with air and moisture

Methodology Applied

Scientific EffectPassivation:

Implementation Method 2

surface modifiers applied to passivate lithium

Methodology Applied

Scientific EffectAdsorption: Adsorption

Implementation Method 3

reducing the severity of volume expansion, thereby reducing mechanical stress from volume expansion and contraction

Methodology Applied

Scientific EffectVolume expansion constraint:

Data Source

PatentUS11522178B2Passivated pre-lithiated micron and sub-micron group IVA particles and methods of preparation thereof

Publication Date: 2022.12.06 PARACLETE ENERGY INC

AI summary

A method of producing a negative electrode, including comminuting Li-Group IVA alloy particles in a solvent to a desired particle size distribution range, exposing surfaces of the Li-Group IVA alloy particles to at least one surface modifier present during the comminution process, the at least one surface modifier forming at least one continuous coating on at least one of the exposed surfaces of the Li-Group IVA alloy particles, removing the solvent, and adding the surface-modified Li-Group IVA alloy particles to a negative electrode material by a coating process.