Battery Cell Coolant Release for Thermal Runaway Suppression

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing secondary battery technologies face challenges in mitigating thermal runaway events, particularly internal short circuits, which are dangerous and costly due to the reliance on external cooling methods that increase battery mass and cost, and are ineffective for flexible cell cases like soft pouch or prismatic cells.

Innovation Solution

A battery system with a sealed case and thermally conductive terminals that include a non-electrically conductive hydrofluoroether coolant with a low boiling point, allowing direct cooling of electrodes and incorporating a thermally sensitive actuator to release coolant during overheating, thereby preventing thermal runaway through phase change and vaporization.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If external cooling methods are used to mitigate thermal runaway, then thermal safety is improved, but battery mass and cost increase

Engineering Contradiction:
Improvethermal safetyVSAvoidbattery mass
Core Design Contradiction:
ReliabilityVSWeight of moving object

Solution Approach 1:

The coolant is nested within the battery cell structure itself, specifically stored in the terminal housing rather than requiring external cooling systems. This internal placement eliminates the need for separate external cooling apparatus, reducing overall system mass while maintaining thermal safety through the phase change mechanism of the coolant.

Inventive Principle:
Principle #7Nested doll (Nesting)

Solution Approach 2:

The battery cell serves its own cooling function through the thermally activated dispensing system. When thermal runaway is detected, the cell automatically dispenses its own coolant from the terminal housing without requiring external intervention or additional active cooling components, thereby reducing system mass and complexity.

Inventive Principle:
Principle #25Self-service

2Reliability

If external cooling methods are used to mitigate thermal runaway, then thermal safety is improved, but manufacturing cost increases

Engineering Contradiction:
Improvethermal safetyVSAvoidmanufacturing cost
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The cooling function is merged with the existing terminal structure of the battery cell. The terminal housing serves dual purposes: electrical connection and coolant storage/dispensing mechanism. This integration eliminates the need for separate external cooling systems, reducing component count and manufacturing cost while maintaining thermal safety.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The battery cell includes its own cooling capability through the integrated terminal-based dispensing system, eliminating the need for expensive external cooling infrastructure. The cell autonomously manages its thermal safety, reducing overall system cost while maintaining reliability.

Inventive Principle:
Principle #25Self-service

3Object-affected harmful factors

If coolant is released during thermal runaway, then thermal event is suppressed, but cell structure complexity increases

Engineering Contradiction:
Improvethermal runaway suppressionVSAvoidcell structure
Core Design Contradiction:
Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The coolant utilizes phase transition (freezing point depression) to activate the dispensing mechanism. When thermal runaway occurs, the heat causes the frozen coolant to melt and expand, automatically opening the dispensing channel without requiring mechanical actuators or complex control systems. This simple physics-based mechanism suppresses thermal runaway while minimizing structural complexity.

Inventive Principle:
Principle #36Phase transitions

Solution Approach 2:

The complex active control systems are extracted from the design, replaced by a passive physics-based dispensing mechanism. The terminal housing contains the coolant and dispensing structure, which automatically activates through thermal expansion and phase change, eliminating the need for sensors, pumps, or electronic controls while maintaining effective thermal suppression.

Inventive Principle:
Principle #2Taking out (Extraction)

4Temperature

If traditional cooling systems are used, then thermal management is achieved, but the system requires pumps and complex apparatus prone to failure

Engineering Contradiction:
Improvethermal managementVSAvoidsystem reliability
Core Design Contradiction:
TemperatureVSReliability

Solution Approach 1:

The battery cell autonomously manages its own thermal conditions through the integrated dispensing system. When thermal runaway is detected, the cell automatically releases its coolant without requiring external pumps or active control systems, eliminating components prone to failure and improving overall system reliability.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The mechanical pump-based cooling systems are replaced with a passive thermal response mechanism. The dispensing system activates automatically through thermal expansion and phase change of the coolant, eliminating mechanical moving parts that are prone to failure while achieving effective thermal management.

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 solution effectively suppresses thermal runaway events with reduced mass and cost, rendering cells inert by expelling electrolyte and preventing further heat generation, while allowing the use of thermally non-conductive materials and minimizing coolant volume and weight.

Implementation Method 1

incorporating a thermally sensitive actuator to release coolant during overheating, thereby preventing thermal runaway through phase change and vaporization

Methodology Applied
Scientific EffectPhase change: Phase Change

Implementation Method 2

preventing thermal runaway through phase change and vaporization

Methodology Applied
Scientific EffectVaporization: Evaporation

Implementation Method 3

thermally conductive terminals that include a non-electrically conductive hydrofluoroether coolant with a low boiling point, allowing direct cooling of electrodes

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Data Source

PatentEP3867969B1Thermal management of electrochemical storage devices
Publication Date: 2024.12.04 ELECTRIC POWER SYSTEMS INC
  • EP3867969B1 patent drawingFigure 1
  • EP3867969B1 patent drawingFigure 2
  • EP3867969B1 patent drawingFigure 3

AI summary

Electrochemical cell battery systems and associated methods of operation are provided based on the incorporation of a thermal suppression construct including a supply of an electrically non-conductive, non-flammable, coolant. The coolant provides a first cooling method that benefits the cells by cooling them during normal operating modes and provides a second cooling method in the case of high temperature abnormal situations wherein the coolant is dispensed internal to the cell to cool the electrode directly and render the cell inert.