Multi-Stage Oxygen Compressor for Lithium-Oxygen Battery Thermal Management

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Lithium-oxygen batteries face challenges such as dendrite formation, moisture protection, achieving high specific energy and power levels, reducing voltage hysteresis, and improving cycle life, which limit their commercial viability for electric vehicles.

Innovation Solution

A vehicular battery system with a multi-stage oxygen compressor and closed oxygen handling system, where oxygen is compressed and stored on board, allowing for efficient and compact oxygen management, and a battery control system to regulate temperature and flow rates, ensuring efficient energy use and minimizing contamination risks.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a single-stage compressor is used to compress oxygen to high pressure (>100 bar), then the system structure is simple, but the temperature rise is excessive and energy efficiency is low

Engineering Contradiction:
Improvecompressor structureVSAvoidcompression energy efficiency
Core Design Contradiction:
Device complexityVSLoss of energy

Solution Approach 1:

The compression process is divided into multiple stages with intermediate cooling periods. The compressor includes a first stage that compresses oxygen to intermediate pressure, followed by a first cooling period, then a second stage that compresses to final high pressure, followed by a second cooling period. This segmentation reduces temperature rise and improves energy efficiency compared to single-stage compression.

Inventive Principle:
Principle #1Segmentation

2Use of energy by moving object

If oxygen is stored at high pressure in a compact reservoir, then the vehicle range is extended and energy density is improved, but the risk of contamination and safety hazards increases

Engineering Contradiction:
Improvevehicle rangeVSAvoidcontamination risk
Core Design Contradiction:
Use of energy by moving objectVSObject-affected harmful factors

Solution Approach 1:

The system uses a closed-loop architecture where oxygen is compressed and stored in a sealed reservoir, isolated from the external environment. The multi-stage compression with intermediate cooling prevents overheating and maintains system integrity. The electrolyte circulation system also provides thermal management, creating a controlled inert environment that prevents contamination while enabling high-pressure storage for extended range.

Inventive Principle:
Principle #39Inert atmosphere (Inert environment)

3Use of energy by moving object

If high-capacity positive electrode materials are used with lithium metal negative electrode, then the specific energy is greatly increased, but the voltage hysteresis and cycle life are reduced

Engineering Contradiction:
Improvespecific energyVSAvoidcycle life
Core Design Contradiction:
Use of energy by moving objectVSReliability

Solution Approach 1:

The system employs advanced electrode materials with optimized properties: the positive electrode uses high-capacity materials such as Li2O, BiF3, or FeF3, while the negative electrode uses lithium metal or lithium alloys. The electrolyte composition is specifically tailored to enable stable cycling with these high-capacity materials. The multi-stage compression and thermal management systems maintain optimal operating conditions, allowing the battery to achieve high specific energy while improving cycle life through controlled parameters.

Inventive Principle:
Principle #35Parameter changes

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 system achieves a compact, efficient, and cost-effective method for compressing and storing oxygen, enhancing battery performance, reducing energy losses, and increasing the vehicle's range while ensuring safety and minimizing external contamination.

Implementation Method 1

a multi-stage compressor operably connected to the reservoir and configured to compress oxygen into the reservoir

Methodology Applied
Scientific EffectGas compression: Compression

Implementation Method 2

a radiator operably connected to the compressor and configured to cool the compressed oxygen

Methodology Applied
Scientific EffectHeat exchange: Heat Exchanger

Implementation Method 3

Lithium-oxygen batteries face challenges such as dendrite formation, moisture protection, achieving high specific energy and power levels

Methodology Applied
Scientific EffectElectrochemical reaction: Redox Reactions

Data Source

PatentEP2976804B1Metal/oxygen battery with multistage oxygen compression
Publication Date: 2018.07.04 ROBERT BOSCH GMBH
  • EP2976804B1 patent drawingFigure 1
  • EP2976804B1 patent drawingFigure 2~3
  • EP2976804B1 patent drawingFigure 4~5

AI summary

A vehicular battery system includes a vehicular battery system stack including at least one negative electrode including a form of lithium, an oxygen reservoir having a first outlet operably connected to the vehicular battery system stack, a multistage compressor having a first inlet operably connected to the vehicular battery system stack, and a second outlet operably connected to a second inlet of the oxygen reservoir, and a cooling system operably connected to the multistage compressor and configured to provide a coolant to the multistage compressor to cool a compressed fluid within the multistage compressor.