Patterned Silicon Electrode Structure for Battery Swelling Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Rechargeable batteries face challenges in achieving high capacity while maintaining cell lifespan due to volume changes associated with the use of silicon-based active materials, which can lead to short circuits and reduced lifespan.
Innovation Solution
The electrode design includes a substrate with a lower carbon-based layer, a middle silicon-based pattern layer with higher expansion properties, and an upper layer, along with a filling layer to minimize volume expansion, using a slot die coating device to form these layers simultaneously, ensuring the silicon-based active material maintains high capacity without deteriorating electrical properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If silicon-based active material is used to achieve high capacity, then battery capacity is improved, but volume expansion occurs during charging and discharging leading to reduced lifespan
Solution Approach 1:
The electrode is divided into multiple functional layers: a lower layer with carbon-based active material, a middle layer with silicon-based active material arranged in a specific pattern, and an upper layer with carbon-based active material. This segmentation allows the silicon-based material to contribute high capacity while the carbon-based layers constrain volume expansion and maintain structural integrity during charging and discharging cycles.
Solution Approach 2:
The electrode employs a composite structure combining carbon-based active material and silicon-based active material in specific layers. The carbon-based material provides structural stability and resistance to volume expansion, while the silicon-based material delivers high capacity. This composite approach enables the electrode to simultaneously achieve high capacity and long lifespan.
2Quantity of substance
If silicon-based active material is used to achieve high capacity, then battery capacity is improved, but short circuiting occurs due to resin phase growth
Solution Approach 1:
The electrode is segmented into distinct layers with carbon-based active material in the upper and lower layers, and silicon-based active material in the middle layer. This segmentation isolates the silicon-based material that is prone to resin phase growth, preventing it from causing short circuits while still allowing it to contribute to high capacity through its high theoretical capacity.
Solution Approach 2:
Different regions of the electrode have different material compositions tailored to their specific functions. The carbon-based layers provide structural stability and resistance to resin phase growth, while the silicon-based middle layer provides high capacity. This local differentiation of material properties enables the electrode to simultaneously achieve high capacity and reliability.
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
This configuration effectively limits volume expansion, enhancing the battery's lifespan and maintaining high capacity by using a silicon-based active material, while the slot die coating device ensures efficient and uniform layer formation.
Implementation Method 1
the viscosity of the upper layer and the filling layer may be equal to about 3,000±1,500 mPas, and the viscosity of the pattern layer may be equal to about 9,500±4,500 mPas
Data Source
AI summary
An example embodiment of the present disclosure provides an electrode for a rechargeable battery, the electrode including a substrate, a lower layer formed on the substrate and including a plurality of portions, a pattern layer formed on the lower layer, a filling layer formed on the lower layer and located between the portions of the pattern layer, and an upper layer formed on the pattern layer and the filling layer.