Electrochemical Cell Additives for Lithium Anode Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Rechargeable batteries with metallic lithium anodes exhibit limited cycle lifetimes, necessitating improvements in cycle lifetime and performance.
Innovation Solution
Incorporating a first additive with a xanthate group and a second additive with an (oxalato)borate group into the electrolyte of electrochemical cells, with the second additive present at greater than or equal to 0.2 wt% and a ratio of total additive weights less than or equal to 3, to enhance the passivation of electrodes and reduce decomposition.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If metallic lithium anodes are used to achieve high energy density, then energy density is improved, but cycle lifetime deteriorates
Solution Approach 1:
The patent introduces a dual-additive system comprising a xanthate compound and an (oxalato)borate compound as intermediary substances in the electrolyte. These additives mediate between the metallic lithium anode and the electrolyte, forming protective interface layers that prevent direct harmful interactions while allowing lithium ion transport, thus extending cycle lifetime without sacrificing energy density
Solution Approach 2:
The patent modifies the chemical composition parameters of the electrolyte by incorporating specific compounds: a xanthate compound at 0.01-5 wt% and an (oxalato)borate compound at ≥0.2 wt%, with their weight ratio controlled at ≤3. This parameter change transforms the electrolyte's interfacial properties, enabling stable SEI formation on lithium anodes and improving cycle stability
2Ease of manufacture
If conventional electrolyte compositions are used, then manufacturing simplicity is maintained, but electrode decomposition increases
Solution Approach 1:
The xanthate and (oxalato)borate additives enable the electrolyte to self-organize and form protective interface layers on the electrodes during initial cycling. This self-service mechanism automatically prevents electrode decomposition without requiring external intervention or complex manufacturing processes, maintaining ease of manufacture while eliminating harmful decomposition
Solution Approach 2:
The patent creates a composite electrolyte system combining conventional electrolyte components with xanthate and (oxalato)borate additives. This composite formulation synergistically combines the simplicity of conventional electrolytes with the protective benefits of the additives, preventing electrode decomposition while maintaining manufacturing simplicity
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 combination of xanthate and (oxalato)borate additives in the electrolyte significantly improves the cycle life of electrochemical cells by reducing unwanted reactions and decomposition, leading to enhanced performance and extended battery life.
Implementation Method 1
enhance the passivation of electrodes and reduce decomposition
Implementation Method 2
cathode active material reduction and oxidation electrochemical processes generally involve lithium ions
Data Source
Figure 1A
Figure 1B
Figure 1C
AI summary
Articles and methods involving electrochemical cells including first and second passivating agents resp. articles and processes for production of or use in such electrochemical cells are provided.