Composite Battery Enclosure With Two-Stage Thermal Runaway Venting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithium-ion batteries face issues with thermal runaway due to lack of effective venting mechanisms, leading to potential chemical reactions and structural integrity failures, especially in laminated aluminum pouch cells which can experience seal failures and galvanic corrosion.
Innovation Solution
A composite enclosure design featuring a multilayer polymeric laminated film and a metal cell can enclosure with a two-stage vent system, utilizing dissimilar metals with varying melting points to create a controlled venting mechanism during thermal runaway events, and incorporating a foam layer for expansion absorption and thermal interface material for heat management.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a metal cell can enclosure is used to provide structural protection, then strength and durability are improved, but thermal runaway venting capability deteriorates
Solution Approach 1:
The metal cell can enclosure is segmented into different material regions: a first portion made of aluminum alloy and a second portion made of steel alloy. This segmentation allows each portion to serve different functions - the aluminum portion provides controlled venting during thermal runaway while the steel portion maintains structural integrity
Solution Approach 2:
Different portions of the enclosure have different material properties tailored to their specific functions. The aluminum alloy portion has lower melting point for controlled venting, while the steel alloy portion has higher melting point for structural support. This local differentiation of material quality resolves the contradiction between venting capability and structural strength
2Volume of moving object
If laminated aluminum pouch cells are used to reduce package space, then volume efficiency is improved, but seal integrity and corrosion resistance deteriorate
Solution Approach 1:
The invention uses a composite enclosure structure combining metal cell can (aluminum and steel alloys) with laminated pouch cells. The metal enclosure provides robust seal integrity and corrosion resistance, while the laminated pouch cells maintain volume efficiency. This composite approach resolves the contradiction between compact packaging and seal reliability
3Reliability
If dissimilar metals with varying melting points are used in the enclosure, then thermal runaway control is improved, but manufacturing complexity increases
Solution Approach 1:
The enclosure is divided into separate aluminum alloy and steel alloy portions that can be manufactured independently using standard processes, then assembled together. This segmentation reduces manufacturing complexity compared to creating a single complex alloy, while still achieving the desired thermal runaway control through the dissimilar metal combination
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 composite enclosure design enhances thermal management, prevents galvanic corrosion, maintains structural integrity, and effectively directs hot gases away from sensitive areas during thermal runaway, ensuring safer operation and prolonged battery life.
Implementation Method 1
One of the plurality of faces is constructed with a first metal with a relatively low melting point... The sacrificial portion is constructed with a first metal including a relatively low melting point
Implementation Method 2
a layer of foam material configured for absorbing volumetric expansion of at least one of the electrodes
Implementation Method 3
a layer of thermal interface material adjacent to an interior surface of the metal cell can enclosure
Data Source
AI summary
A battery including a composite enclosure is provided. The battery includes a metal cell can enclosure including a plurality of faces. One of the plurality of faces is configured for locally failing during a thermal runaway event. The battery further includes a multilayer polymeric laminated film and a battery cell including a pair of electrodes including an anode and a cathode, a separator, and an electrolyte. The battery cell is hermetically sealed within the multilayer polymeric laminated film. The multilayer polymeric laminated film is contained within the metal cell can enclosure.