Electrochemical Cell Voltage Screening Under Compression

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods fail to detect abnormal self-discharge in electrochemical cells before assembly into batteries or modules, leading to economic and environmental losses due to defective cells causing entire battery or module discard, and potential recall campaigns.

Innovation Solution

A method and apparatus for monitoring self-discharge in electrochemical cells by arranging and compressing cells along a specific direction, measuring voltage differences, and discarding cells with abnormal self-discharge before assembly, using a support structure and detection system to identify latent defects.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If cells are monitored only after assembly into batteries or modules, then manufacturing complexity is reduced, but defective cells cannot be detected early leading to economic and environmental losses

Engineering Contradiction:
Improvedefect detection capabilityVSAvoidmonitoring system complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies preliminary action by monitoring cells during the storage phase before they are assembled into batteries or modules. The system measures voltage at multiple time points (t0, t1, t2) during storage to calculate self-discharge rates, enabling early detection of defective cells with latent metal contamination or separator damage before assembly occurs. This prevents defective cells from being incorporated into final battery products.

Inventive Principle:
Principle #10Preliminary action

2Reliability

If all cells are compressed and monitored before assembly, then defect detection improves, but processing time and energy consumption increase

Engineering Contradiction:
Improveself-discharge detection accuracyVSAvoidmonitoring process time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The patent applies partial action by monitoring only a subset of cells during the storage phase rather than all cells. The system identifies cells exhibiting abnormal self-discharge characteristics (excessive voltage drop over time) and flags them for further investigation or discarding. This selective approach reduces processing time and energy consumption compared to monitoring every cell, while still achieving reliable defect detection for cells with latent contamination or damage.

Inventive Principle:
Principle #16Partial or excessive action

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

Enables early detection of defective cells, preventing assembly into batteries or modules, reducing economic and environmental impact by avoiding full battery discard and recall campaigns.

Implementation Method 1

measuring a voltage of each cell of the plurality of cells to detect whether a self-discharge value of the cell is above a predetermined threshold

Methodology Applied
Scientific EffectVoltage measurement: Ohm's Law

Implementation Method 2

compressing the cells along a third direction, which is orthogonal to a first direction and to a second direction

Methodology Applied
Scientific EffectCompression: Compression

Data Source

PatentEP4671797A1Method and apparatus for monitoring self-discharge phenomena of electrochemical cells
Publication Date: 2025.12.31 FERRARI SPA
  • EP4671797A1 patent drawingFigure 1
  • EP4671797A1 patent drawingFigure 2
  • EP4671797A1 patent drawingFigure 3a~3b

AI summary

A method for monitoring self-discharge phenomena of electrochemical cells, comprising the steps of: a) providing a plurality of electrochemical cells (2), wherein each cell (2) has a first dimension and a second dimension, extending respectively along a first direction (X) and a second direction (Y) orthogonal to one another, greater than a third dimension extending along a third direction (Z) orthogonal to the first direction (X) and the second direction (Y), wherein each cell (2) comprises a casing (3) and a plurality of layers arranged inside the casing (3), wherein the layers comprise at least one first electrode layer, at least one second electrode layer and at least one first separator layer interposed between the first electrode layer and the second electrode layer; b) arranging the cells (2) so that a straight line (L) extending along the third direction (Z) intersects the cells (2); c) compressing the cells (2) along the third direction (Z); d) measuring a voltage of each cell (2) of the plurality of cells (2) to detect whether a self-discharge value of said cell (2) is greater than a predetermined threshold, wherein step c) is prior to or at least partially simultaneous with step d), and step d) is prior to a step of assembling the cells (2) into one or more batteries. Figure 1