LDH Separator Structure for Blocking Zinc Dendrite Penetration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Secondary zinc batteries face short circuits due to metallic zinc dendrites penetrating through separators, leading to reduced service life, despite the use of layered double hydroxide (LDH) separators that selectively permeate hydroxide ions and block zinc dendrites.
Innovation Solution
A LDH separator is created by plugging pores of a porous polymeric substrate with LDH, resulting in flattened remaining pores with non-parallel longitudinal directions to the separator's thickness, effectively diverting and preventing zinc dendrite growth.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional separator composed of non-woven fabrics is used, then the battery structure is simple and manufacturing is easy, but zinc dendrites penetrate through the separator causing short circuits
Solution Approach 1:
The patent uses a composite separator structure consisting of a porous substrate combined with an LDH (layered double hydroxide) coating layer. This composite structure provides both the mechanical integrity of the substrate and the dendrite-blocking properties of the LDH layer, effectively preventing zinc dendrite penetration while maintaining battery reliability
Solution Approach 2:
The patent employs a porous substrate as the base structure of the separator. The porous structure allows for ion transport while providing a framework for the LDH coating. The porosity is controlled to balance ion conductivity and dendrite prevention, with the LDH layer filling and modifying the pore structure to block dendrite growth paths
2Reliability
If the LDH separator is made dense to block zinc dendrites, then short circuit prevention is improved, but hydroxide ion conductivity may be reduced
Solution Approach 1:
The patent applies local quality by creating an LDH coating layer with specific properties on the surface and within the pores of the porous substrate. The LDH layer is dense enough to block zinc dendrites locally at the pore interfaces, while the overall porous structure maintains channels for hydroxide ion transport. This localized densification prevents dendrites without completely blocking ion pathways
Solution Approach 2:
The patent optimizes parameters including the thickness of the LDH layer, the porosity of the substrate, and the crystalline structure of the LDH to achieve the right balance. By controlling these parameters, the separator maintains sufficient hydroxide ion conductivity while the LDH structure provides effective dendrite blocking through its layered morphology and interlayer spacing
3Reliability
If the porous substrate is completely plugged with LDH to prevent dendrite penetration, then short circuit prevention is improved, but the separator loses flexibility and ion transport pathways
Solution Approach 1:
The patent applies partial action by filling only a portion of the porous substrate structure with LDH material, rather than completely plugging all pores. The LDH coating is applied to the pore walls and interfaces, providing dendrite blocking at critical locations while leaving sufficient open pathways for ion transport. This partial filling maintains both dendrite resistance and ion conductivity
Solution Approach 2:
The patent segments the separator into two functional components: the porous substrate providing mechanical support and ion transport pathways, and the LDH coating layer providing dendrite blocking. This segmentation allows each component to optimize its specific function without compromising the other, with the substrate maintaining flexibility and the LDH layer providing targeted protection against dendrite penetration
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 LDH separator significantly enhances the prevention of short circuits by maintaining high hydroxide ion conductivity and flexibility while restricting zinc dendrite penetration, thereby extending the battery's service life.
Implementation Method 1
layered double hydroxide (LDH) separators that selectively permeate hydroxide ions while blocking the penetration of zinc dendrites
Implementation Method 2
by plugging pores of a porous polymeric substrate with LDH and flattening the pores remaining in the porous substrate
Data Source
AI summary
Provided is a layered double hydroxide (LDH) separator including a porous substrate made of a polymeric material, and LDH with which pores of the porous substrate are plugged. The LDH separator has a plurality of remaining flattened pores, longitudinal directions of the pores being non-parallel to a thickness direction of the LDH separator.