Lithium-Ion Battery Plating Diagnosis via Multi-Temperature EIS

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Solution Overview

Problem

Existing methods for diagnosing lithium plating in lithium ion batteries often require disassembly, which is irreversible and inconvenient, and conventional electrochemical impedance spectroscopy is typically performed at a single temperature, limiting its effectiveness in detecting lithium plating.

Innovation Solution

Utilizing electrochemical impedance spectroscopy at different temperatures to analyze lithium ion batteries, where the trend of the Nyquist plot curves indicates the presence of lithium plating, allowing for non-invasive diagnosis.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If visual observation techniques (naked eye, optical microscope, SEM or TEM) are used to detect lithium plating, then detection capability is improved, but the battery must be disassembled causing irreversible damage

Engineering Contradiction:
Improvelithium plating detection capabilityVSAvoidbattery integrity
Core Design Contradiction:
Measurement precisionVSReliability

Solution Approach 1:

The patent replaces mechanical disassembly and physical observation methods with electrochemical impedance spectroscopy, an electrical measurement technique. This substitution allows detection of lithium plating through electrical impedance changes without mechanical intervention, thereby maintaining battery integrity while achieving detection capability.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces electrochemical impedance spectroscopy as an intermediary measurement method that indirectly detects lithium plating. Instead of directly observing lithium metal morphology, the method uses impedance spectral characteristics as a mediator to infer plating conditions, enabling non-invasive detection.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Ease of operation

If conventional electrochemical impedance spectroscopy is performed at a single temperature, then measurement simplicity is improved, but detection effectiveness for lithium plating is limited

Engineering Contradiction:
Improvemeasurement simplicityVSAvoidlithium plating detection accuracy
Core Design Contradiction:
Ease of operationVSMeasurement precision

Solution Approach 1:

The patent changes the temperature parameter during electrochemical impedance spectroscopy measurement. By performing measurements at multiple temperatures and analyzing the variation patterns of impedance spectral characteristics, the method enhances lithium plating detection accuracy while maintaining operational simplicity through automated temperature cycling.

Inventive Principle:
Principle #35Parameter changes

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 quick and non-destructive detection of lithium plating by observing the change in the real part of the Nyquist plot with temperature, providing a reliable standard for evaluating lithium plating in lithium ion batteries.

Implementation Method 1

Electrochemical impedance spectroscopy (EIS) is a widely used tool for characterizing lithium ion batteries

Methodology Applied
Scientific EffectElectrochemical impedance spectroscopy:

Implementation Method 2

The result is usually presented in the form of a Nyquist plot. The Nyquist plot contains two 'semicircles'

Methodology Applied
Scientific EffectImpedance spectroscopy:

Implementation Method 3

the curve in the Nyquist plot of electrochemical impedance spectroscopy shows a tendency to increase in the real part (horizontal axis direction) as the temperature increases

Methodology Applied
Scientific EffectTemperature dependence of electrochemical impedance:

Data Source

PatentEP4200933B1Method for diagnosing lithium plating in lithium ion batteries by using electrochemical impedance spectroscopy
Publication Date: 2025.05.14 BAYERISCHE MOTOREN WERKE AG
  • EP4200933B1 patent drawingFigure 1
  • EP4200933B1 patent drawingFigure 2~3
  • EP4200933B1 patent drawingFigure 4~5

AI summary

The invention relates to the field of lithium ion batteries, and in particular to a method for diagnosing lithium plating in lithium ion batteries by using electrochemical impedance spectroscopy.