Battery Cell Overpressure Sensor with Flexible Element

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional high-performance battery cells face reliability issues due to non-energetic and energetic failures, particularly thermal runaway, which poses a significant safety risk and requires effective detection and handling to prevent propagation within battery modules or packs.

Innovation Solution

A battery arrangement with an overpressure safety element, comprising a flexible element and a switch, is designed to detect and handle thermal runaway events by activating a safety measure before severe damage occurs, using a combination of burst discs and an extinguishing agent to manage internal gas pressure and prevent further damage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If conventional vent openings and current interrupting devices are used in battery cells, then thermal runaway can be partially managed, but detection precision and early warning capability are insufficient

Engineering Contradiction:
Improvethermal runaway detection precisionVSAvoidsafety device complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The flexible element is pre-installed on the cell housing to detect pressure changes before thermal runaway fully develops. This preliminary detection mechanism triggers warnings or safety measures in advance, improving detection precision without requiring complex real-time monitoring systems.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The flexible element acts as an intermediary between the internal cell pressure and the external warning system. It translates internal pressure changes into mechanical displacement that can activate switches or sensors, providing simple yet effective detection without complex electronics inside the cell.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Productivity

If high-performance battery cells with higher energy density are deployed, then productivity and power output increase, but the risk and severity of thermal runaway events increase

Engineering Contradiction:
Improvebattery power outputVSAvoidthermal runaway severity
Core Design Contradiction:
ProductivityVSObject-affected harmful factors

Solution Approach 1:

The overpressure safety element provides preliminary anti-action by detecting pressure buildup from thermal runaway and triggering safety measures before the event propagates. This prevents the harmful effects from spreading to other cells or modules, counteracting the increased risk associated with higher energy density batteries.

Inventive Principle:
Principle #9Preliminary anti-action

Solution Approach 2:

The internal gas pressure, which is a harmful symptom of thermal runaway, is converted into a useful detection signal. The flexible element uses this pressure to activate safety mechanisms, turning the harmful physical phenomenon into a beneficial warning and protection system.

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

3Reliability

If multiple safety measures are implemented to prevent thermal runaway propagation, then reliability improves, but device complexity and manufacturing cost increase

Engineering Contradiction:
Improvebattery safety reliabilityVSAvoidsafety system complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The safety system is segmented into simple, modular components: the flexible element mounted on the cell housing and external switches or sensors. This segmentation allows the safety function to be added to individual cells without complicating the overall battery system architecture, maintaining reliability while minimizing complexity.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The flexible element is designed to be self-activating, using the internal pressure itself to trigger the safety response. This self-service mechanism eliminates the need for complex electronic sensors, processors, or power supplies within the safety device, improving reliability through simplicity.

Inventive Principle:
Principle #25Self-service

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 effectively detects and mitigates thermal runaway events, preventing propagation and ensuring safety by triggering a shutdown or releasing gases and extinguishing agents, thus protecting the battery cell and connected devices from severe damage.

Implementation Method 1

the flexible element is deformed by a gas overpressure within the battery cell and that the flexible element activates the switch when a predetermined overpressure within the battery cell is reached or exceeded

Methodology Applied
Scientific EffectGas overpressure: Pressure Increase

Data Source

PatentEP4224608A1Battery arrangement and battery cell
Publication Date: 2023.08.09 ABB (SCHWEIZ) AG
  • EP4224608A1 patent drawingFigure 1~2
  • EP4224608A1 patent drawingFigure 3~4
  • EP4224608A1 patent drawingFigure 5~6

AI summary

A battery arrangement is provided. The battery arrangement comprises at least one battery cell (20) comprising at least two electrical terminals (30, 32) and a cell housing (21); and at least one overpressure sensor comprising a flexible element (42, 52, 54) being formed and/or arranged at the cell housing (21), and a switch (44) being arranged outside of the cell housing (21) and being coupled or couplable to the flexible element (42, 52, 54), wherein the overpressure sensor and the flexible element (42, 52, 54) are formed and arranged such that the flexible element (42, 52, 54) is deformed by a gas overpressure within the battery cell (20) and that the flexible element (42, 52, 54) activates the switch (44) when a predetermined overpressure within the battery cell (20) is reached or exceeded.