LiMn2O4 Cathode Photo-Assisted Fast Charging With Lower Heating

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Lithium-ion batteries experience slow charging and potential degradation due to resistive heating during fast direct current charging, which limits their efficiency and usability.

Innovation Solution

Irradiating the cathode electrode with broadband white light during charging to lower charge-transfer resistance and enhance electrochemical reactions, allowing for faster charging without significant heating or degradation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If fast direct current charging is applied to lithium-ion batteries, then charging speed is improved, but temperature increases due to resistive heating causing battery degradation

Engineering Contradiction:

Improvecharging speedVSAvoidresistive heating

Core Design Contradiction:

ProductivityVSObject-affected harmful factors

Solution Approach 1:

The patent replaces the conventional electrical charging mechanism with a photo-assisted charging mechanism. Light irradiation (optical energy) is used to generate electron-hole pairs in the cathode material, which facilitates lithium ion extraction and charging. This substitution of electrical field-driven charging with photo-induced charging reduces resistive heating while maintaining fast charging capability.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the charging mechanism from electrical field-driven to photo-induced by altering the energy input parameter. Instead of applying high current that causes i²R heating, the system uses light irradiation to directly generate charge carriers in the cathode, fundamentally changing how energy is transferred to the battery system and eliminating the primary source of resistive heating.

Inventive Principle:

Principle #35Parameter changes

2Loss of time

If fast charging is performed on lithium-ion batteries, then charging time is reduced, but battery degradation occurs due to heat generation

Engineering Contradiction:

Improvecharging timeVSAvoidbattery cycle life

Core Design Contradiction:

Loss of timeVSReliability

Solution Approach 1:

The patent replaces conventional electrical charging with photo-assisted charging using light irradiation. This substitution enables fast charging by directly generating electron-hole pairs in the cathode material through photon absorption, which facilitates rapid lithium ion extraction without the resistive heating that normally causes battery degradation and limits charging speed.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces light (photons) as an intermediary energy carrier in the charging process. Instead of directly applying electrical current that generates heat, the system uses light irradiation as a mediator to induce photo-excitation in the cathode material, which then drives the electrochemical reactions. This intermediary approach enables fast charging while avoiding the thermal degradation pathways.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Reliability

If conventional charging methods are used, then battery safety is maintained, but charging speed is limited due to heating concerns

Engineering Contradiction:

Improvebattery safetyVSAvoidcharging speed

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

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 method enables faster charging with minimal heating, resulting in higher energy density and longer battery cycle life by reducing kinetic and thermodynamic barriers, thereby improving the overall efficiency and performance of lithium-ion batteries.

Implementation Method 1

Irradiating the cathode electrode with broadband white light during charging to lower charge-transfer resistance and enhance electrochemical reactions

Methodology Applied

Scientific EffectPhotoexcitation: Photoelectric Effect

Data Source

PatentUS12166184B2Photo-assisted fast charging of lithium manganese oxide spinel (LiMn<sub>2</sub>O<sub>4</sub>) in lithium-ion batteries

Publication Date: 2024.12.10 UCHICAGO ARGONNE LLC

AI summary

A process for charging a discharged electrochemical cell includes applying a voltage bias to the discharged electrochemical cell; and illuminating the cathode with a light source.