Modular EQCM Test Cell for Hermetic Electrochemical Characterization

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current EQCM cell designs for lithium-ion battery characterization are cumbersome, require excessive electrolyte, and cannot be used outside a glove box due to non-hermetical sealing and suboptimal electrode arrangement, leading to high costs and inefficiencies in laboratory testing.

Innovation Solution

A modular EQCM test cell design featuring a compact structure with closely positioned electrodes, reduced electrolyte volume, and hermetical sealing using alignment elements, O-ring-seals, and a modular structure allowing for easy assembly and disassembly, enabling accurate characterization outside a glove box.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If electrodes are arranged side by side with immersion from top of cell, then electrode assembly is simple, but electrode arrangement does not reproduce operational battery conditions and increases electrode distance

Engineering Contradiction:
Improveelectrode assembly simplicityVSAvoidelectrode arrangement accuracy
Core Design Contradiction:
Ease of manufactureVSManufacturing precision

Solution Approach 1:

The cell is divided into separate components (cell body, cell hood, alignment elements) that can be assembled independently. The alignment elements are segmented into multiple features (protrusions, recesses, grooves) that work together to precisely position electrodes face-to-face, reproducing operational battery conditions while maintaining assembly simplicity.

Inventive Principle:
Principle #1Segmentation

2Reliability

If argon and water circulation circuits are added to the cell, then temperature regulation and atmosphere control are improved, but cell structure becomes cumbersome and mobile

Engineering Contradiction:
Improvetemperature control stabilityVSAvoidcell structure complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The temperature control and atmosphere control functions are extracted from the cell structure itself and placed in external systems. The cell is designed with simple through-openings for electrolyte filling and electrode insertion, while temperature regulation and argon atmosphere control are handled by external equipment, reducing cell complexity and improving portability.

Inventive Principle:
Principle #2Taking out (Extraction)

3Ease of operation

If large quantity of electrolyte is used to immerse electrodes, then electrode coverage is sufficient, but electrolyte consumption is excessive and cost increases

Engineering Contradiction:
Improveelectrode coverage adequacyVSAvoidelectrolyte volume
Core Design Contradiction:
Ease of operationVSQuantity of substance

Solution Approach 1:

The electrode arrangement transitions from top-down immersion to face-to-face configuration. This dimensional change allows electrodes to be positioned close together horizontally, creating an efficient electrolyte pathway between them. The electrolyte only needs to fill the narrow gap between electrodes rather than covering large electrode surfaces, dramatically reducing electrolyte volume requirements.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

4Ease of operation

If cell is designed without hermetic sealing, then assembly and disassembly is easy, but cell cannot be taken out from glove box and requires continuous expensive equipment usage

Engineering Contradiction:
Improvecell assembly simplicityVSAvoidhermetic sealing capability
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The cell is segmented into modular components (cell body, cell hood, alignment elements) connected by simple mechanical features. This segmentation allows easy assembly and disassembly for electrode replacement while maintaining hermetic sealing through O-rings and alignment grooves, enabling the cell to be removed from the glove box after initial assembly.

Inventive Principle:
Principle #1Segmentation

5Manufacturing precision

If modular structure with alignment elements and O-ring-seals is implemented, then hermetic sealing and electrode positioning precision are improved, but device complexity increases

Engineering Contradiction:
Improveelectrode positioning accuracyVSAvoidcell structure complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

Multiple functions are merged into the alignment elements: mechanical positioning of electrodes, hermetic sealing through O-ring grooves, and structural alignment of cell components. This integration achieves precise electrode positioning and hermetic sealing without adding separate complex systems, as the alignment elements serve multiple purposes simultaneously.

Inventive Principle:
Principle #5Merging (Combining)

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 allows for precise and cost-effective characterization of electrochemical systems with minimal electrolyte usage, enabling accurate measurement of mass variations and voltage differences, and facilitating the use of the EQCM system in hermetic conditions, reducing experimental costs and improving operational efficiency.

Implementation Method 1

An EQCM is a device capable of measuring a mass variation by using a resonance generated by the piezoelectric effect of a quartz crystal

Methodology Applied
Scientific EffectPiezoelectric effect: Piezoelectric Effect

Implementation Method 2

measuring a frequency change occurring on the working electrode... the value of the resonance frequency varies due to the variation of the mass of the working electrode

Methodology Applied
Scientific EffectResonance: Resonance

Implementation Method 3

at least one O-ring-seal arranged at an edge of the cell body and/or cell basis and/or cell hood... each O-ring-seal comprising a sealing material having a defined elasticity

Methodology Applied
Scientific EffectElasticity: Elasticity

Data Source

PatentEP3757062A1Test cell for the EQCM characterization of electrochemical systems, and method for the EQCM characterization of electrochemical systems
Publication Date: 2020.12.30 CENT NAT DE LA RECH SCI (C N R S)
  • EP3757062A1 patent drawingFigure 1~2
  • EP3757062A1 patent drawingFigure 3~4
  • EP3757062A1 patent drawingFigure 5~6

AI summary

The invention relates to a test cell for the EQCM - Electrochemical Quartz Crystal Microbalance- characterization of an electrochemical system comprising a liquid electrolyte, characterized in that said test cell comprises: - a cell body (10) comprising a first through-opening (11) extending through the cell body (10) along a predefined axis Z, said first through-opening (11) being intended to host the electrolyte, the cell body (10) comprising also a first electrode of the electrochemical system, called working electrode (13), and a quartz resonator (12) at an end of the first through-opening (11), the quartz resonator (12) being intended to support said working electrode (13), the quartz resonator (12) being configured for providing a signal function of a mass variation of the working electrode (13), - a cell basis (20), configured to be assembled with the cell body (10) along axis Z, and comprising a laterally arranged connecting terminal (22), said connecting terminal (22) being electrically connectable to the quartz resonator (12) for receiving the signal from the quartz resonator (12), - a cell hood (30), configured to be assembled with the cell body (10) along axis Z, comprising a second through-opening (31) extending through the cell hood (30) substantially along the axis Z, and a second electrode of the electrochemical system, called counter-electrode, said second through-opening (31) being intended to host the counter-electrode (32), - at least one O-ring-seal (50, 51, 52, 53), said O-ring-seal (50, 51, 52, 53) being arranged at an edge of the cell body (10) and/or cell basis (20) and/or cell hood (30), in a plane normal to axis Z.