Battery Cell-Stack Compression via Volatile Vapor Bellows

Solution Overview

Problem

Existing battery pressure management systems for ultralight aircraft are excessively heavy or complex, making them unsuitable for long-endurance solar-powered aircraft applications.

Innovation Solution

A lightweight battery pack assembly featuring a sealed pressurized bellows or piston device filled with a volatile vapor, which applies a constant force to compress the battery cell-stack, eliminating the need for heavy or complex structural components.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If metallic or plastic structural methods are used to withstand the necessary applied load, then the battery pressure management system can maintain constant pressure, but the system becomes excessively heavy and complex

Engineering Contradiction:

Improvepressure managementVSAvoidbattery assembly weight

Core Design Contradiction:

ReliabilityVSWeight of moving object

Solution Approach 1:

The patent employs a pneumatic system where a sealed container filled with a compressible gas or fluid applies pressure to the battery cell stack. This replaces heavy metallic structural methods with a lighter pneumatic mechanism that can maintain constant pressure through the compressibility and elasticity of the gas/fluid, resolving the contradiction between reliable pressure management and weight reduction

Inventive Principle:

Principle #29Pneumatics and hydraulics

Solution Approach 2:

The invention changes the physical state parameters by using a compressible gas or fluid medium instead of rigid structural components. The gas/fluid's compressibility allows it to absorb cell swelling while maintaining constant pressure, achieving reliable pressure management with significantly reduced weight compared to metallic structures

Inventive Principle:

Principle #35Parameter changes

2Reliability

If metallic or plastic structural methods are used to withstand the necessary applied load, then the battery pressure management system can maintain constant pressure, but the system becomes overly complex

Engineering Contradiction:

Improvepressure managementVSAvoidstructural complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent employs a pneumatic system where a sealed container filled with a compressible gas or fluid applies pressure to the battery cell stack. This replaces heavy metallic structural methods with a lighter pneumatic mechanism that can maintain constant pressure through the compressibility and elasticity of the gas/fluid, resolving the contradiction between reliable pressure management and weight reduction

Inventive Principle:

Principle #29Pneumatics and hydraulics

Solution Approach 2:

The compressible gas or fluid medium automatically adjusts to cell swelling and shrinking cycles, maintaining constant pressure without requiring external control systems or complex mechanical components. The system self-regulates through the inherent physical properties of the gas/fluid, reducing overall device complexity

Inventive Principle:

Principle #25Self-service

3Weight of moving object

If a sealed container with volatile vapor is used to compress the cell-stack, then the pressure management system becomes lightweight, but the container must withstand the necessary applied load

Engineering Contradiction:

Improvepressure management system weightVSAvoidcontainer load bearing capacity

Core Design Contradiction:

Weight of moving objectVSStrength

Solution Approach 1:

The invention changes the physical state parameters by using a compressible gas or fluid medium instead of rigid structural components. The gas/fluid's compressibility allows it to absorb cell swelling while maintaining constant pressure, achieving reliable pressure management with significantly reduced weight compared to metallic structures

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent utilizes a sealed container that can be relatively lightweight because it contains a compressible medium rather than needing to be a heavy rigid structure itself. The container's walls can be thinner and lighter since the primary load-bearing function is performed by the compressible gas/fluid medium, not the container structure

Inventive Principle:

Principle #30Flexible shells and thin films

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 provides a lightweight, efficient pressure management system that maintains constant pressure over a range of displacements, enhancing battery performance and longevity while reducing weight and manufacturing costs.

Implementation Method 1

a sealed container housing a volatile vapor, wherein the sealed container is positioned within the battery enclosure and configured to impart a force to compress the cell-stack

Methodology Applied

Scientific EffectVapor pressure: Vapour Pressure

Data Source

PatentUS10840487B2System, method, and apparatus for battery cell-stack compression

Publication Date: 2020.11.17 META PLATFORMS INC

AI summary

The present disclosure relates to the manufacture of battery packs/assemblies and more specifically, the manufacture of battery packs/assemblies for use in aircraft. A lightweight battery assembly with cell compression and/or pressure management system is disclosed herein. The cell compression and/or pressure management system can employ a sealed container housing a volatile vapor. The sealed container can be positioned within the battery enclosure and configured to impart a force to compress the cell-stack.