Metal Ion Battery Fabric Envelope Spark Containment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Metal ion batteries, such as lithium ion batteries, are vulnerable to fires due to thermal runaway, which can cause exothermic reactions, gas production, and potential ignition from sparks during thermal runaway, leading to pressure buildup and risk of explosion.
Innovation Solution
A metal ion battery cell design featuring a safety valve for gas venting and a fabric envelope that surrounds the housing to contain sparks and prevent ignition of gases, with the fabric envelope being gas permeable to release excess gases and oxygen-free to prevent fires, and made from heat-resistant materials to withstand high temperatures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stress or pressure
If a safety valve is used to vent gases during thermal runaway, then pressure buildup is prevented, but sparks can escape and ignite flammable gases
Solution Approach 1:
A fabric envelope acts as an intermediary component between the battery housing and the external environment. The envelope is positioned to surround the housing and intercept sparks before they can reach flammable gases in the surrounding atmosphere, while still allowing vented gases to pass through to the external environment.
Solution Approach 2:
The fabric envelope creates a protective zone around the battery housing that prevents oxygen from reaching sparks and flammable gases simultaneously. By surrounding the housing with the envelope, the space between the housing and envelope becomes an oxygen-depleted environment that cannot support combustion, even when sparks and gases are present.
2Object-affected harmful factors
If the fabric envelope is made gas impermeable to contain gases, then gas containment is improved, but back-pressure builds up at the safety valve
Solution Approach 1:
The fabric envelope is constructed from porous material that allows gas molecules to pass through while physically blocking larger spark particles. The porous structure provides selective permeability based on particle size, enabling gas containment without creating back-pressure that would interfere with safety valve operation.
Solution Approach 2:
The fabric envelope has different functional properties at different scales: at the macro level, it acts as a physical barrier to sparks and flames; at the micro level, the porous structure allows gas permeability. This local quality differentiation enables simultaneous spark arrestment and gas venting without back-pressure buildup.
3Object-affected harmful factors
If the fabric envelope fully surrounds the housing to eliminate oxygen, then fire prevention is improved, but gas venting capability is reduced
Solution Approach 1:
The fabric envelope utilizes porous material properties to achieve selective filtering. The pore size is designed to be small enough to block oxygen diffusion and spark particles, yet large enough to allow free passage of vented gases. This enables the envelope to create an oxygen-depleted zone for fire prevention while maintaining gas venting capability.
Solution Approach 2:
The fabric envelope is made from composite materials that combine fire-resistant properties with controlled porosity. The composite structure provides both the mechanical strength to fully surround the housing and the selective permeability needed for gas venting, achieving simultaneous fire prevention and gas venting functions.
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 effectively reduces the risk of fire and explosion by containing sparks and gases within an oxygen-free environment, preventing ignition and maintaining safety during thermal runaway events.
Implementation Method 1
a fabric envelope surrounding the housing, such that sparks generated by the battery cell are contained by the fabric envelope
Implementation Method 2
The fabric envelope may be gas permeable, to allow gas to pass from within the envelope to outside the envelope when the pressure within the envelope is greater than the pressure outside the envelope
Implementation Method 3
The safety valve may be a one way valve arranged to open at 0.9 MPa, or 0.9 MPa±0.2 MPa pressure within the metal ion battery cell
Data Source
AI summary
The present invention concerns a fire safety arrangement for a battery. More particularly, but not exclusively, this invention concerns a fire safety arrangement for a metal ion battery, for example a lithium ion battery cell. The metal ion battery cell comprises a plurality of electrodes and an electrolyte encased within a housing. The housing comprises a safety valve or vent to allow gas build up within the housing to vent outside the housing, and a fabric envelope surrounding the housing. Any sparks generated by the battery are contained within the fabric envelope, thereby reducing or eliminating the chances of fire or explosion.