Composite Protective Layer for Lithium Electrodes Against Dendrites
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional lithium secondary batteries face challenges with high energy density, dendrite formation, and reduced cycle lifetime due to the reactivity of lithium metal electrodes, which leads to internal short circuits and capacity loss.
Innovation Solution
A lithium electrode with a protective layer comprising a two-dimensional material and a polymer of intrinsic microporosity is developed, preventing dendrite formation and enhancing lithium ion transport, thereby improving battery performance and stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a protective layer is formed on the lithium metal negative electrode to prevent dendrite formation, then the stability and lifetime characteristics of the battery are improved, but the uniform distribution of lithium ions and the formation of an effective solid electrolyte interfacial layer are hindered
Solution Approach 1:
The patent applies composite materials by combining polymer of intrinsic microporosity (PIM) with lithium dendrite absorbing materials in the protective layer. This composite structure allows the PIM component to provide uniform lithium ion distribution through its microporous structure, while the lithium dendrite absorbing material component suppresses dendrite growth, thus resolving the contradiction between improving battery stability and maintaining uniform lithium ion distribution.
2Quantity of substance
If lithium metal is used as a negative electrode to increase energy density, then the capacity and energy density of the battery are improved, but dendrite formation and internal short circuits occur due to the high reactivity of lithium metal
Solution Approach 1:
The patent uses a protective layer as an intermediary between the lithium metal negative electrode and the electrolyte. This protective layer, composed of PIM and lithium dendrite absorbing materials, mediates the interaction by preventing direct contact between lithium metal and electrolyte, thereby suppressing dendrite formation and internal short circuits while allowing lithium ions to pass through, thus maintaining high energy density without compromising reliability.
3Reliability
If a polymer protective film is formed on the lithium metal electrode to suppress dendrite growth, then the stability is improved, but the uniform distribution of lithium ions on the surface of the electrode is hindered
Solution Approach 1:
The patent resolves this contradiction by creating a composite protective layer where PIM provides microporous channels for uniform lithium ion distribution, while lithium dendrite absorbing materials suppress dendrite growth. The synergistic combination of these two components in the composite structure allows both functions to coexist, maintaining battery stability while ensuring uniform lithium ion distribution on the electrode surface.
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 protective layer effectively suppresses dendrite growth, maintains conductivity, and extends the battery's cycle life and capacity retention, addressing the limitations of previous protective layer technologies.
Implementation Method 1
a protective layer formed on a surface of the lithium metal layer, wherein the protective layer comprises a two-dimensional material and a polymer of intrinsic microporosity
Data Source
AI summary
A lithium electrode and a lithium secondary battery comprising the same are provided. The lithium electrode comprises a protective layer, which contains a two-dimensional material and a polymer of intrinsic microporosity, on a surface of a lithium metal layer, and suppresses formation of dendrites and improves the transfer characteristics for lithium ions, thereby providing extended lifetime of the lithium secondary battery.