Fuel Cell Vehicle Heat Exchanger Layout for Cab Space Limits

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional fuel cell vehicles face challenges in securing both mountability and sufficient cooling performance for radiators due to limited space below the cab, which is often occupied by steering devices and other components.

Innovation Solution

A cooling device for fuel cell vehicles that utilizes dead spaces outside the vehicle width direction of hydrogen gas reservoirs to mount large heat exchangers, incorporating an outside air guide and fans to enhance cooling performance, and separates coolant pathways for different components to optimize cooling efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the radiator is installed below the cab to achieve cooling function, then the cooling ability is provided, but the mounting space is limited due to steering device and other components

Engineering Contradiction:
Improvecooling performanceVSAvoidmounting space
Core Design Contradiction:
ReliabilityVSArea of stationary object

Solution Approach 1:

The patent transitions from installing the radiator in the vertical dimension below the cab to installing it in the horizontal dimension at the rear side of the cab, outside the vehicle width direction of the hydrogen gas reservoir. This dimensional change exploits previously unused space and enables a larger radiator mounting area without interfering with steering components.

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

Solution Approach 2:

The radiator is extracted from the conventional location below the cab and repositioned to the rear side of the cab, outside the hydrogen gas reservoir. This separation allows the radiator to be mounted in a location with sufficient space while maintaining its cooling function.

Inventive Principle:
Principle #2Taking out (Extraction)

2Reliability

If a large radiator is installed to achieve sufficient cooling performance, then the cooling ability is improved, but the space utilization becomes difficult due to limited mounting area

Engineering Contradiction:
Improvecooling performanceVSAvoidspace utilization
Core Design Contradiction:
ReliabilityVSAdaptability or versatility

Solution Approach 1:

By moving the radiator to the rear side of the cab in the horizontal dimension, the patent accesses a three-dimensional space that is not constrained by the vehicle width, allowing installation of a large radiator with sufficient cooling performance while effectively utilizing available space.

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

3Area of stationary object

If the heat exchanger is installed outside the vehicle width direction of the hydrogen gas reservoir, then the mounting space is enlarged, but the space is previously considered as dead space

Engineering Contradiction:
Improvemounting spaceVSAvoidspace utilization
Core Design Contradiction:
Area of stationary objectVSAdaptability or versatility

Solution Approach 1:

The patent extracts and utilizes the dead space located outside the vehicle width direction of the hydrogen gas reservoir for mounting the heat exchanger. This transforms previously wasted space into functional mounting area, enlarging the available space for the radiator.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The space outside the hydrogen gas reservoir, which was previously unused dead space, is now serving dual purposes: maintaining hydrogen storage functionality while providing mounting space for the heat exchanger. This multi-functional utilization optimizes space efficiency.

Inventive Principle:
Principle #6Universality (Multi-functionality)

4Reliability

If multiple radiators are arranged below the cab as disclosed in Patent Document 1, then the cooling ability is secured, but the mounting space remains limited

Engineering Contradiction:
Improvecooling abilityVSAvoidmounting space
Core Design Contradiction:
ReliabilityVSArea of stationary object

Solution Approach 1:

Instead of arranging multiple radiators in the limited space below the cab, the patent extracts the radiator from this constrained location and repositions it to the rear side of the cab, where a single large radiator can provide equivalent or superior cooling ability with sufficient mounting space.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent moves the radiator arrangement from the vertical dimension below the cab to the horizontal dimension at the rear side, outside the vehicle width. This dimensional transition provides ample space for a large radiator without requiring multiple units.

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

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 ensures both mountability and enhanced cooling performance, allowing for efficient cooling of fuel cells, high-voltage batteries, and motors, while reducing component count and optimizing space utilization.

Implementation Method 1

a heat exchanger that is installed outside in the vehicle width direction of the hydrogen gas reservoir and along the hydrogen gas reservoir, and that exchanges heat between outside air and coolant configured to cool at least the fuel cell

Methodology Applied
Scientific EffectHeat exchange: Heat Exchanger

Implementation Method 2

exchanges heat between outside air and coolant

Methodology Applied
Scientific EffectConvection: Convection

Implementation Method 3

exchanges heat between outside air and coolant

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 4

The outside air guide may include a fan that generates a flow of the outside air that passes through the heat exchanger

Methodology Applied
Scientific EffectForced convection: Forced Convection

Data Source

PatentEP4431327B1Cooling device for fuel cell vehicle
Publication Date: 2026.02.25 DAIMLER TRUCK AG
  • EP4431327B1 patent drawingFigure 1
  • EP4431327B1 patent drawingFigure 2
  • EP4431327B1 patent drawingFigure 3

AI summary

A cooling device (1) for a fuel cell vehicle (2) that includes a cab (21) and a chassis frame (22) and that drives a motor (24) for traveling with electric power of a fuel cell (23) includes a hydrogen gas reservoir (3) and a heat exchanger (4). The hydrogen gas reservoir (3) is installed on a rear side of the cab (21) and outside in a vehicle width direction (D2) of the chassis frame (22), and stores hydrogen gas to be supplied to the fuel cell (23). The heat exchanger (4) is installed outside in the vehicle width direction (D2) of the hydrogen gas reservoir (3) and along the hydrogen gas reservoir (3), and exchanges heat between outside air and coolant (41) configured to cool at least the fuel cell (23).