Prelithiated Porous Silicon Anodes for Fast-Charging Durability

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Lithium-ion batteries based on silicon anodes face challenges such as manufacturing complexity, fragility, and limited market impact due to issues like volume expansion, pulverization, and handling stresses, which hinder their widespread adoption despite silicon's high theoretical storage capacity.

Innovation Solution

A method involving a current collector with a metal oxide layer and a continuous porous lithium storage layer deposited by CVD, which is prelithiated before assembly, enhancing stability, durability, and manufacturing simplicity, and allowing for fast charging capabilities.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If silicon-based anodes are used to replace carbon-based anodes, then charge capacity is improved, but volume expansion and pulverization occur

Engineering Contradiction:

Improvecharge capacityVSAvoidstructural integrity

Core Design Contradiction:

Quantity of substanceVSStrength

Solution Approach 1:

The silicon anode is divided into discrete silicon particles rather than using bulk silicon layers. This segmentation allows each particle to independently accommodate volume expansion during lithiation, preventing crack propagation and maintaining structural integrity while preserving high charge capacity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

A porous carbon matrix is used as the anode structure to accommodate silicon particles. The porous structure provides void space that absorbs volume expansion of silicon during lithium insertion, preventing pulverization and maintaining electrical connectivity while enabling high charge capacity.

Inventive Principle:

Principle #31Porous materials

2Strength

If nano- or micro-structured silicon is used, then pulverization is reduced, but manufacturing complexity increases

Engineering Contradiction:

Improveresistance to pulverizationVSAvoidmanufacturing complexity

Core Design Contradiction:

StrengthVSDevice complexity

Solution Approach 1:

The invention uses a self-organizing approach where silicon particles are formed in-situ within a porous carbon matrix through a simple dip-coating process. The carbon matrix automatically provides the necessary nano/micro-structure and spacing, eliminating the need for complex top-down fabrication of structured silicon while achieving pulverization resistance.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

A porous carbon matrix is introduced as an intermediary material that simplifies manufacturing. Instead of directly fabricating complex silicon structures, the carbon matrix serves as a template and protective medium, enabling simple solution-based processing while achieving the desired nano/micro-structured silicon anode with improved pulverization resistance.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Ease of manufacture

If conventional carbon-based anodes are used, then manufacturing is simple, but charge capacity is limited

Engineering Contradiction:

Improvemanufacturing simplicityVSAvoidcharge capacity

Core Design Contradiction:

Ease of manufactureVSQuantity of substance

Solution Approach 1:

The anode is designed as a composite material system combining carbon and silicon. The carbon component provides structural framework and electrical conductivity with simple manufacturability, while dispersed silicon particles contribute high charge capacity. This composite approach maintains manufacturing simplicity while dramatically increasing charge capacity compared to pure carbon anodes.

Inventive Principle:

Principle #40Composite materials

4Quantity of substance

If silicon anodes are used, then charge capacity is improved, but physical durability decreases

Engineering Contradiction:

Improvecharge capacityVSAvoidphysical durability

Core Design Contradiction:

Quantity of substanceVSReliability

Solution Approach 1:

Each silicon particle is embedded within a flexible carbon matrix that can deform to accommodate silicon volume changes during cycling. This flexible carbon shell/constraint structure maintains physical durability by preventing particle breakage and disconnection while allowing the silicon to expand and contract, preserving high charge capacity over many cycles.

Inventive Principle:

Principle #30Flexible shells and thin films

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 provides lithium-ion batteries with improved stability at aggressive charging rates, higher areal charge capacity, enhanced physical durability, and a more reproducible manufacturing process, addressing the limitations of traditional silicon anodes.

Implementation Method 1

A continuous porous lithium storage layer is deposited onto the metal oxide layer by a CVD process

Methodology Applied

Scientific EffectChemical Vapour Deposition: Chemical Vapour Deposition

Data Source

PatentUS12199284B2Anodes for lithium-based energy storage devices, and methods for making same

Publication Date: 2025.01.14 GRAPHENIX DEVELOPMENT INC

AI summary

A prelithiated anode may include a current collector may include a metal oxide layer. Prelithiated anodes may in addition include a lithiated storage layer overlaying the metal oxide layer. The lithiated storage layer may be formed by incorporating lithium into a continuous porous lithium storage layer may include at least 80 atomic % silicon. The lithiated storage layer may include less than 1% by weight of carbon-based binders. The lithiated storage layer may further include lithium in a range of 1% to 90% of a theoretical lithium storage capacity of the continuous porous lithium storage layer. Batteries may include the prelithiated anode.