Fuel Cell Stack Case Through-Hole Layout for Lead Misalignment

Solution Overview

Problem

The misalignment of power lead-out members with their respective through-holes due to assembly and dimensional tolerances in fuel cell systems leads to insertion failures and reduces the rigidity of the stack case.

Innovation Solution

Designing the second through-hole in the stack case to be longer than the first through-hole in the stacking direction compensates for positional variations of the second terminal member, ensuring reliable insertion of the power lead-out member while maintaining the rigidity of the stack case.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the length of the second through-hole in the stacking direction is increased to compensate for misalignment, then the reliability of power lead-out member insertion is improved, but the rigidity of the upper wall portion deteriorates

Engineering Contradiction:

Improveinsertion reliabilityVSAvoidrigidity

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The patent applies local quality by making only the second through-hole elongated in the stacking direction while keeping the first through-hole with normal dimensions. This localized modification allows the second through-hole to accommodate misalignment without affecting the overall rigidity of the upper wall portion, as the elongation is confined to a specific area rather than the entire structure.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent segments the solution by treating the two through-holes differently - the first through-hole maintains standard dimensions while the second through-hole is specifically elongated. This segmentation allows targeted compensation for misalignment at the second through-hole location without requiring universal dimensional increases that would compromise structural rigidity.

Inventive Principle:

Principle #1Segmentation

2Ease of operation

If the length of each through-hole in the stacking direction is set to be large in advance to ensure alignment, then the ease of insertion is improved, but the rigidity of the upper wall portion deteriorates

Engineering Contradiction:

Improveease of insertionVSAvoidrigidity

Core Design Contradiction:

Ease of operationVSStrength

Solution Approach 1:

The patent applies local quality by making only the second through-hole elongated in the stacking direction while keeping the first through-hole with normal dimensions. This localized modification allows the second through-hole to accommodate misalignment without affecting the overall rigidity of the upper wall portion, as the elongation is confined to a specific area rather than the entire structure.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent segments the solution by treating the two through-holes differently - the first through-hole maintains standard dimensions while the second through-hole is specifically elongated. This segmentation allows targeted compensation for misalignment at the second through-hole location without requiring universal dimensional increases that would compromise structural rigidity.

Inventive Principle:

Principle #1Segmentation

Data Source

PatentUS12355125B2Fuel cell system

Publication Date: 2025.07.08 HONDA MOTOR CO LTD

AI summary

A first through-hole through which a first power lead-out member is inserted and a second through-hole through which a second power lead-out member is inserted are formed in an upper wall portion of a stack case of a fuel cell system. The length of the second through-hole in the stacking direction of the power generation cells is greater than the length of the first through-hole in the stacking direction.