Binder for Battery Anode Managing Volume Expansion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithium batteries face challenges with the low capacity of carbon-based materials and the short lifespan of metal alloy anodes due to volume changes during charge and discharge, necessitating a binder that can enhance battery life and accommodate these changes.
Innovation Solution
A binder composition incorporating polymethyl methacrylate particles and a binder polymer, with specific particle size and weight ratios, and optionally a silane-based coupling agent, is used to improve the strength and elastic modulus of the binder, allowing it to effectively accommodate volume changes of anode active materials during lithium battery operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If metal alloy anode materials (Si, Sn, Al) are used to increase capacity, then battery capacity is improved, but electrode volume changes during charge-discharge causing short battery life
Solution Approach 1:
The binder uses temperature-dependent viscoelasticity, changing from rigid at room temperature to flexible at elevated temperatures during battery operation, to dynamically adapt to volume changes of metal alloy anode materials while maintaining structural integrity
Solution Approach 2:
The binder is a composite system combining polymethyl methacrylate particles with a binder polymer matrix, creating a material that exhibits both rigid support and flexible accommodation properties to handle electrode volume changes
2Reliability
If carbon-based anode materials are used to ensure stability, then battery reliability is improved, but battery capacity remains low due to porous structure
Solution Approach 1:
The binder's glass transition temperature is optimized to be below room temperature, allowing it to maintain appropriate flexibility and adhesion properties under normal battery operating conditions while providing stable binding
3Strength
If binder strength is increased to maintain electrode integrity, then electrode structural stability is improved, but ability to accommodate volume change is reduced
Solution Approach 1:
The binder exhibits dynamic mechanical properties that change with temperature, being rigid at low temperature for structural support and flexible at high temperature during battery operation to accommodate volume changes of active materials
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 binder composition enhances the cycle characteristics and lifespan of lithium batteries by maintaining high elastic modulus at elevated temperatures and reducing electrode expansion, thereby improving the battery's overall performance and life.
Implementation Method 1
the binder composition enhances the cycle characteristics and lifespan of lithium batteries by maintaining high elastic modulus at elevated temperatures
Implementation Method 2
A binder composition incorporating polymethyl methacrylate particles and a binder polymer, with specific particle size and weight ratios, and optionally a silane-based coupling agent
Data Source
AI summary
A binder for a battery including polymethyl methacrylate particles and a binder polymer is disclosed. Additionally, a binder composition, and an anode and a lithium battery which include the binder are also disclosed.