Selenium-Carbon Composite Electrodes for Safe Rechargeable Batteries
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithium sulfur batteries face issues with low sulfur utilization, severe capacity fade, and short lifetimes due to their insulating nature and solubility of intermediary polysulfides during charge-discharge, requiring high temperature operation which poses safety concerns.
Innovation Solution
Development of selenium-based electroactive materials, including selenium-carbon composites, that operate at temperatures below the melting point of selenium, utilizing carbon electronic conductors and binders to enhance conductivity and stability, allowing for safer and more efficient battery performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If lithium sulfur batteries are operated at high temperature to improve electrochemical activity, then battery performance is enhanced, but safety risks and thermal stability deteriorate
Solution Approach 1:
The patent changes the operating temperature parameter from high temperature (above melting point of selenium) to lower temperature (below melting point of selenium, specifically 0-100°C or -100 to 150°C), thereby improving safety while maintaining battery performance through the use of selenium-based electroactive materials with appropriate conductivity modifiers
Solution Approach 2:
The patent employs composite materials consisting of selenium-based electroactive materials combined with conductivity modifiers (such as carbon materials, metal sulfides, or metal selenides) to achieve both high performance and safety at lower operating temperatures, avoiding the need for high temperature operation
2Quantity of substance
If sulfur-based materials are used to achieve high specific capacity, then energy density is improved, but sulfur utilization and cycle life deteriorate due to insulating character and polysulfide solubility
Solution Approach 1:
The patent changes the electroactive material from sulfur-based to selenium-based, exploiting the different chemical and electrical properties of selenium to overcome the insulating character and polysulfide solubility issues that plague lithium sulfur batteries, thereby improving both capacity utilization and cycle life
Solution Approach 2:
The patent creates composite materials where selenium-based electroactive materials are combined with conductivity modifiers (carbon materials, metal sulfides, or metal selenides) to simultaneously improve electrical conductivity, sulfur/selenium utilization, and cycle stability by preventing intermediary compound solubility
3Object-affected harmful factors
If selenium-based materials are used to operate below melting point for safety, then thermal stability is improved, but electrical conductivity may deteriorate
Solution Approach 1:
The patent employs composite materials where selenium-based electroactive materials are combined with conductivity modifiers (such as carbon materials, metal sulfides, or metal selenides) to maintain high electrical conductivity at lower operating temperatures, eliminating the need for high temperature operation while preserving performance
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 selenium-based materials achieve high capacity and long charge-discharge lifetimes, offering safer and more stable battery operation at lower temperatures compared to lithium sulfur batteries, with improved thermal stability and reduced safety risks.
Implementation Method 1
a material is provided including selenium, a selenium-containing compound, selenium-carbon composite, a selenium-containing compound-carbon composite, or a mixture thereof; where the material is an electroactive material at a temperature of below 280° C.
Implementation Method 2
the carbon electronic conductor includes synthetic graphite, natural graphite, amorphous carbon, hard carbon, soft carbon, acetylene black, MCMB, carbon black, Ketjen black, mesoporous carbon, porous carbon matrix, carbon nanotube, carbon nanofiber, or graphene
Data Source
AI summary
An electrode includes selenium, a selenium-containing compound, selenium-carbon composite, a selenium-containing compound-carbon composite, or a mixture thereof; a carbon electronic conductor; a binder; and a current collector; wherein: the electrode is a solid electrode.