Battery Pack Pressure Release via Elastic Deformation Gap

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional pressure release valves for battery packs in electric vehicles are structurally weak, leading to potential oxidization reactions and damage from external factors like stepping stones, as they rely on breaking or melting mechanisms that fail to maintain pack integrity after pressure release.

Innovation Solution

The pressure release mechanism utilizes elastic deformation of the pack casing to create a gap for gas discharge, with a plate-like member fixed at two locations, allowing for controlled pressure release without compromising the pack's structural strength and re-sealing to prevent oxygen ingress.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If a lid member enclosing the opening section is made weak to enable pressure release through breakage or melting, then gas can escape quickly, but the pack casing strength is reduced and structural integrity is compromised

Engineering Contradiction:
Improvepressure release speedVSAvoidpack casing strength
Core Design Contradiction:
ProductivityVSStrength

Solution Approach 1:

The pressure release function is segmented from the main pack casing structure. A separate plate-like member (sealing plate) is used to enclose the opening section, while the pack casing itself maintains its full structural strength. The sealing plate is designed to break or deform under pressure, while the pack casing remains intact.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The weak element designed for pressure release is extracted as a separate component (sealing plate) from the main pack casing structure. This allows the pack casing to maintain its structural integrity while the sealing plate provides the pressure release function through its controlled breakage or deformation.

Inventive Principle:
Principle #2Taking out (Extraction)

2Productivity

If the lid member is made weak to allow pressure release, then gas can escape, but external air and oxygen can easily flow into the pack casing causing oxidization reactions

Engineering Contradiction:
Improvepressure release speedVSAvoidoxidization resistance
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

A gap adjustment plate is introduced as an intermediary component between the opening section and the external environment. This plate can be adjusted to control the gap size, allowing pressure release while minimizing oxygen ingress. The gap adjustment plate acts as a mediator that balances pressure release needs with oxidation prevention.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The gap size between the sealing plate and opening section can be adjusted by changing the position of the gap adjustment plate. This parameter change allows control over the balance between pressure release effectiveness and oxygen ingress prevention, optimizing both performance and reliability.

Inventive Principle:
Principle #35Parameter changes

3Productivity

If a lid member is used to enclose the opening section for pressure release, then gas can escape, but a new problem of vulnerability to external factors like stepping stones occurs

Engineering Contradiction:
Improvepressure release speedVSAvoidexternal damage vulnerability
Core Design Contradiction:
ProductivityVSObject-affected harmful factors

Solution Approach 1:

The sealing plate is designed as a separate, replaceable component that can be independently managed. If damaged by external factors like stepping stones, only the sealing plate needs to be replaced rather than the entire pack casing, minimizing the impact of external damage.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The design anticipates potential external damage to the sealing plate by making it a sacrificial, replaceable component. The main pack casing structure is protected from direct exposure to external hazards, as the sealing plate serves as the first line of defense that can be damaged without compromising the main structure.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

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 approach enables quick pressure release and subsequent re-sealing, minimizing the risk of oxidization and maintaining pack strength, effectively addressing the weaknesses of existing mechanisms.

Implementation Method 1

the pressure release is, basically, achieved utilizing an elastic deformation of the pack casing itself due to a pressure rise in an inside of the pack casing

Methodology Applied
Scientific EffectElastic deformation: Elasticity

Implementation Method 2

the plate-like member overlapped on the opening section is locally fixed to the wall at two locations across the opening section

Methodology Applied
Scientific EffectFixed attachment:

Data Source

PatentEP3361526B1Pressure release mechanism for battery pack
Publication Date: 2020.05.13 NISSAN MOTOR CO LTD
  • EP3361526B1 patent drawingFigure 1~2
  • EP3361526B1 patent drawingFigure 3~4
  • EP3361526B1 patent drawingFigure 5(a)~6

AI summary

[Abstract] A pressure release mechanism (11) for a battery pack (1) is constituted by a circular opening section (12) and a gap adjustment plate (13). The gap adjustment plate (13) is fixed to a wall (5A) through a pair of fixtures (14) mutually opposed against each other via the opening section (12). When gas is generated due to an internal short-circuiting of any one or more of cells or so forth, the battery pack performs an elastic deformation trying to expand by itself. A gap (ΔL) is developed in association with a bending deformation of a wall (5A) surrounding the opening section (12) in a direction orthogonal to the pair of fixtures (14). A high pressure gas in an inside of the pack casing (2) is discharged externally via the gap (ΔL).