Sodium-Halogen Battery Intermediate Temperature Operation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional sodium-based rechargeable batteries operate at high temperatures, leading to thermal management issues, safety concerns, and high energy costs due to the need for maintaining molten electrodes and ceramic electrolytes, which limits their efficiency and power density.
Innovation Solution
A sodium-halogen secondary cell design utilizing a sodium ion conductive solid electrolyte membrane and a molten eutectic mixture of sodium haloaluminate salts with a low melting point, allowing operation at intermediate temperatures between 80° C. and 210° C., and featuring a negative electrode of metallic sodium and a positive electrode with a halogen in a molten salt electrolyte.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional high-temperature sodium-based batteries use molten electrodes and ceramic electrolytes, then ionic conductivity is maintained, but thermal management issues and safety concerns arise
Solution Approach 1:
The patent changes the operating temperature parameter from high temperature (conventional molten salt batteries operating above 200°C) to intermediate temperature (80°C to 210°C) by using a eutectic mixture of sodium haloaluminate salts that melts at lower temperatures, thereby improving safety while maintaining ionic conductivity
Solution Approach 2:
The patent uses a composite electrolyte system combining solid sodium ion conductive membrane with molten eutectic sodium haloaluminate salt, where the solid membrane provides structural stability and the molten salt provides high ionic conductivity at lower temperatures, resolving the contradiction between safety and conductivity
2Use of energy by moving object
If molten electrodes and ceramic electrolytes are used to maintain ionic conductivity, then energy costs increase due to heating requirements
Solution Approach 1:
The patent changes the melting point parameter of the electrolyte from high (requiring continuous heating) to low (80°C to 210°C operating range) by using eutectic sodium haloaluminate salts, significantly reducing the heating energy required to maintain operational temperature and improving overall energy efficiency
3Power
If conventional high-temperature batteries are used, then power density is limited, but thermal management complexity increases
Solution Approach 1:
The patent changes the operating temperature parameter to an intermediate range (80°C to 210°C) using eutectic sodium haloaluminate salts, which enables higher power density while reducing thermal management complexity compared to conventional high-temperature systems, as the lower operating temperature reduces thermal gradients and cooling requirements
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 design enhances the efficiency and reversibility of sodium-halogen batteries, reducing energy costs and improving safety by maintaining high conductivity at lower temperatures, thus overcoming the limitations of conventional high-temperature sodium-based batteries.
Implementation Method 1
a sodium ion conductive solid electrolyte membrane
Implementation Method 2
a positive electrolyte that comprises one or more sodium haloaluminate salts and a sodium halide... utilizing a molten eutectic mixture of sodium haloaluminate salts having a relatively low melting point
Implementation Method 3
Batteries are known devices that are used to store and release electrical energy for a variety of uses. In order to produce electrical energy, batteries typically convert chemical energy directly into electrical energy
Implementation Method 4
During discharge, electrochemical reduction occurs at the cell's positive electrode, while electrochemical oxidation occurs at the cell's negative electrode
Implementation Method 5
During discharge, electrochemical reduction occurs at the cell's positive electrode, while electrochemical oxidation occurs at the cell's negative electrode
Data Source
AI summary
An intermediate temperature sodium-halogen secondary cell that includes a negative electrode compartment housing a negative, molten sodium-based electrode and a positive electrode compartment housing a current collector disposed in a highly conductive molten positive electrolyte. A sodium halide (NaX) positive electrode is disposed in a molten positive electrolyte comprising one or more AlX3 salts, wherein X may be the same or different halogen selected from Cl, Br, and I, wherein the ratio of NaX to AlX3 is greater than or equal to one. A sodium ion conductive solid electrolyte membrane separates the molten sodium negative electrode from the molten positive electrolyte. The secondary cell operates at a temperature in the range from about 80° C. to 210° C.