Lithium Battery Anode with Bicyclic Sulfate Additive
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithium batteries face challenges with lifespan deterioration and high-temperature stability due to side reactions when using only natural graphite as an anode active material, leading to reduced performance and capacity retention.
Innovation Solution
Incorporating a bicyclic sulfate-based compound in the organic electrolytic solution, along with a combination of natural and artificial graphite as anode active materials, to form a stable solid electrolyte interface (SEI) layer and protection layer, enhancing the battery's high-temperature characteristics and lifespan.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If only natural graphite is used as anode active material, then cost and natural material availability are improved, but lifespan and high-temperature stability deteriorate due to side reactions
Solution Approach 1:
The patent applies composite materials by combining natural graphite (5-50 wt%) with artificial graphite (50-95 wt%) in the anode active material. This composite structure leverages the advantages of both materials: natural graphite provides cost-effectiveness and good lithium insertion/extraction properties, while artificial graphite enhances structural stability and reduces side reactions, thereby improving lifespan and high-temperature stability without completely sacrificing natural material usage
Solution Approach 2:
The patent changes the compositional parameters of the anode by controlling the weight ratio of natural to artificial graphite within specific ranges (natural graphite: 5-50 wt%, artificial graphite: 50-95 wt%). This parameter optimization balances cost considerations with performance requirements, achieving improved reliability while maintaining reasonable use of natural materials
2Reliability
If bicyclic sulfate-based compound is added to electrolytic solution, then high-temperature stability and lifespan are improved through stable SEI layer formation, but device complexity and manufacturing cost increase
Solution Approach 1:
The patent applies local quality by introducing the bicyclic sulfate-based compound specifically at the anode-electrolyte interface where SEI layer formation occurs. This additive locally modifies the chemical environment at the graphite surface, promoting stable SEI formation without fundamentally changing the bulk electrolyte composition or requiring complex system-wide modifications
Solution Approach 2:
The bicyclic sulfate-based compound acts as an intermediary substance that mediates between the graphite anode and the electrolyte. It facilitates the formation of a stable protective SEI layer by reacting with electrolyte components at the interface, thereby improving high-temperature stability and lifespan while maintaining relatively simple overall device architecture
3Reliability
If artificial graphite is increased in anode active material, then lifespan and stability are improved, but cost and use of natural materials decrease
Solution Approach 1:
The patent employs composite materials strategy by creating a blended anode structure containing both artificial graphite (50-95 wt%) for stability and natural graphite (5-50 wt%) for cost-effectiveness. This composite approach allows the system to achieve improved lifespan and stability through the artificial graphite component while preserving a meaningful portion of natural graphite to control costs and maintain sustainability
Solution Approach 2:
The patent optimizes the compositional parameters of the anode by establishing specific weight ratio ranges for natural and artificial graphite. By controlling natural graphite content within 5-50 wt% and artificial graphite within 50-95 wt%, the patent achieves a parameter balance that simultaneously satisfies reliability requirements (through sufficient artificial graphite) and economic/natural material conservation considerations (by maintaining natural graphite presence)
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 use of a bicyclic sulfate-based compound in the electrolyte solution with a mixed graphite anode material significantly improves the lithium battery's discharge capacity, capacity retention, and high-temperature stability, effectively preventing side reactions and maintaining performance over multiple cycles.
Implementation Method 1
Incorporating a bicyclic sulfate-based compound in the organic electrolytic solution, along with a combination of natural and artificial graphite as anode active materials, to form a stable solid electrolyte interface (SEI) layer and protection layer
Implementation Method 2
an organic electrolytic solution between the cathode and the anode. The organic electrolytic solution includes a first lithium salt, an organic solvent, and a bicyclic sulfate-based compound
Data Source
AI summary
A lithium battery includes a cathode including a cathode active material; an anode including an anode active material; and an organic electrolytic solution between the cathode and the anode, wherein the anode active material includes natural graphite and artificial graphite, an amount of the artificial graphite being about 50 wt % or more based on a total weight of the anode active material, and the organic electrolytic solution includes: a first lithium salt; an organic solvent; and a bicyclic sulfate-based compound represented by Formula 1 below:wherein, in Formula 1, each of A1, A2, A3, and A4 is independently a covalent bond, a substituted or unsubstituted C1-C5 alkylene group, a carbonyl group, or a sulfinyl group, in which both A1 and A2 are not a covalent bond and both A3 and A4 are not a covalent bond.