Microchannel Battery Cooler Assembly Without Brazed Tank Joints

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional battery coolers face issues with brazing connections between microchannel tubes and tanks, leading to mechanical property degradation, energy wastage, environmental hazards, increased weight, and coolant leakage, which affect efficiency and fuel economy.

Innovation Solution

A battery cooler design that utilizes over-molding and mechanical connections to secure the microchannel tubes to the tank, eliminating brazing, and incorporates a sealing gasket for leak-proof integrity, using materials like glass-reinforced plastic and EPDM for the tank and gasket.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If brazing is used to connect microchannel tubes to tank, then secure connection is achieved, but mechanical properties of microchannel tubes deteriorate due to excessive heating

Engineering Contradiction:
Improveconnection securityVSAvoidmechanical resistance of microchannel tubes
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The patent replaces the thermal brazing process with a mechanical insertion method where microchannel tubes are inserted into the tank through molded-in recesses. This eliminates the heating process entirely, preserving the mechanical properties of the microchannel tubes while achieving secure connection through precise mechanical fit and sealing elements.

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

2Reliability

If entire microchannel tubes are subjected to brazing, then connection is secured, but energy is wasted and larger furnaces are required

Engineering Contradiction:
Improveconnection securityVSAvoidenergy wastage in brazing furnace
Core Design Contradiction:
ReliabilityVSLoss of energy

Solution Approach 1:

The patent extracts the connection process from the thermal brazing environment and relocates it to a mechanical assembly process. Only the necessary portions of the microchannel tubes (the insertion ends) are involved in the connection, eliminating the need to heat entire tubes or use large furnaces, thereby significantly reducing energy consumption.

Inventive Principle:
Principle #2Taking out (Extraction)

3Reliability

If brazing process is used, then connection is formed, but CO2 emissions increase and working environment becomes hazardous

Engineering Contradiction:
Improveconnection securityVSAvoidCO2 emissions and hazardous working environment
Core Design Contradiction:
ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The patent substitutes the chemical brazing process with a mechanical insertion and sealing method. This eliminates the need for brazing furnaces that emit CO2 and create hazardous working conditions, while achieving equivalent or superior connection security through precision mechanical fits and elastomeric sealing elements.

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

4Reliability

If brazing connection is used, then metallic components are joined, but overall weight of vehicle increases reducing fuel economy

Engineering Contradiction:
Improveconnection securityVSAvoidoverall weight of vehicle
Core Design Contradiction:
ReliabilityVSWeight of moving object

Solution Approach 1:

The patent employs composite construction where the tank is made of plastic material with molded-in recesses and the connection utilizes elastomeric sealing elements combined with mechanical retention features. This plastic-composite approach significantly reduces weight compared to traditional all-metal brazed constructions, improving vehicle fuel economy while maintaining connection integrity.

Inventive Principle:
Principle #40Composite materials

5Weight of moving object

If mechanical connections are used instead of brazing, then weight is reduced, but coolant leakage occurs due to inefficient connection

Engineering Contradiction:
Improveweight of battery coolerVSAvoidcoolant leakage prevention
Core Design Contradiction:
Weight of moving objectVSReliability

Solution Approach 1:

The patent incorporates elastomeric sealing elements (flexible rings or O-rings) at the insertion interface between microchannel tubes and tank. These flexible sealing components deform to conform to the mating surfaces, creating leak-proof seals that prevent coolant leakage while maintaining the lightweight mechanical connection structure.

Inventive Principle:
Principle #30Flexible shells and thin films

6Temperature

If powder coating is applied to microchannel tubes, then heat transfer is enabled, but irregular surfaces are formed at coated-uncoated interfaces causing brazing defects

Engineering Contradiction:
Improveheat transfer capabilityVSAvoidsurface irregularity at interface
Core Design Contradiction:
TemperatureVSManufacturing precision

Solution Approach 1:

The patent extracts the connection interface from the brazing process, eliminating the problem of surface irregularities at coated-uncoated interfaces. The mechanical insertion method tolerates the irregular surfaces created by powder coating, as the elastomeric sealing elements accommodate surface variations without requiring smooth, uniform contact surfaces needed for brazing.

Inventive Principle:
Principle #2Taking out (Extraction)

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 results in a lighter, more efficient, and environmentally friendly battery cooler with reduced carbon footprint, preventing coolant leakage and maintaining performance while avoiding the drawbacks of brazing.

Implementation Method 1

The tank holder is over-molded over extreme ends of the microchannel tube

Methodology Applied
Scientific EffectOver-molding:

Implementation Method 2

The sealing gasket is secured to at least one of the microchannel tube and the tank holder

Methodology Applied
Scientific EffectSealing:

Implementation Method 3

The coating of thermally conductive but electrically insulated material permits heat transfer from the batteries to the coolant flowing through the microchannel tubes

Methodology Applied
Scientific EffectHeat transfer: Conduction (thermal)

Implementation Method 4

a battery cooler having multiple microchannel tubes of aluminum formed by extrusion, Each microchannel tube includes multiple channels

Methodology Applied
Scientific EffectConvection cooling: Convection

Data Source

PatentEP4332421B1A battery cooler
Publication Date: 2025.06.25 VALEO ELECTRIFICATION
  • EP4332421B1 patent drawingFigure 1
  • EP4332421B1 patent drawingFigure 2
  • EP4332421B1 patent drawingFigure 3

AI summary

A battery cooler (100) includes at least one microchannel tube (10), a tank holder (20), a tank (30) and a sealing gasket (40). The microchannel tube (10) includes respective multiple channels (10a) and is formed by extrusion. The tank holder (20) is secured to the microchannel tube (10). The sealing gasket (40) is secured to at least one of the microchannel tube (10) and the tank holder (20). The tank (30) is securely mounted over the tank holder (20). The tank holder (20) is over-molded over at least one extreme end of the microchannel tube (10) and the tank is secured to the tank-holder (20) by mechanical connections.