Fuel Cell Stack Flow Fields with Lateral Water Drainage

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Fuel cell stacks face challenges in draining product water effectively, especially when inclined, leading to channel blockages and uneven gas distribution, which can affect performance and potentially reverse cell polarity.

Innovation Solution

The anode and cathode flow fields are designed with media inlets on their upward-facing sides and are open on their downward-facing sides, allowing direct escape of exhaust gases and product water into adjacent chambers, and integrated liquid separators are used to efficiently separate and drain water, even in inclined positions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If flow fields are inclined to improve water discharge, then water discharge is improved in level ground, but water discharge fails when vehicle is inclined

Engineering Contradiction:

Improvewater discharge reliabilityVSAvoidadaptability to vehicle inclination

Core Design Contradiction:

ReliabilityVSAdaptability or versatility

Solution Approach 1:

Instead of inclining the flow fields to aid drainage, the patent inverts the approach by making flow fields horizontal and opening their downward-facing sides directly into adjacent chambers. This allows water to drain perpendicular to the stacking direction regardless of vehicle inclination, solving the adaptability problem.

Inventive Principle:

Principle #13The other way round (Inversion)

Solution Approach 2:

The patent changes the drainage dimension from vertical (along stacking direction) to lateral (perpendicular to stacking direction). By opening flow fields laterally into adjacent chambers, water can escape in a different dimension that is not affected by vehicle inclination.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

2Device complexity

If outlet channels run through stack in stacking direction, then structure is simple, but channels block with water causing uneven gas distribution

Engineering Contradiction:

Improveflow field structure complexityVSAvoidgas distribution uniformity

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The patent extracts the outlet channel function from the vertical stacking direction and relocates it to lateral openings into adjacent chambers. This removes the water accumulation problem in vertical channels while maintaining structural simplicity.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

Adjacent chambers serve as intermediary spaces that receive water and exhaust gases from flow fields. These chambers act as collection zones that prevent water from blocking the main gas flow paths, ensuring uniform gas distribution.

Inventive Principle:

Principle #24Intermediary (Mediator)

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 design ensures safe and reliable drainage of product water in all orientations, preventing channel blockages and maintaining even gas distribution, thus ensuring the fuel cell stack's performance and preventing polarity reversal.

Implementation Method 1

the discharge of product water formed is improved, even with a corresponding inclined position of the fuel cell stack, as the water can escape directly from the appropriate lateral edge of the flow field

Methodology Applied

Scientific EffectGravity: Gravitation

Data Source

PatentUS9882230B2Fuel cell stack

Publication Date: 2018.01.30 CELLCENTRIC GMBH & CO KG

AI summary

A fuel cell stack has a multiplicity of individual cells, which each include an anode flow field, a membrane electrode arrangement, and a cathode flow field. Each flow field has a media inlet and channels for carrying the media. The anode flow fields and/or the cathode flow fields have the media inlet on their upward-facing side when used as intended, and are open on their downward-facing side when used as intended.