LiBH4 Garnet Composite Electrolyte Separators for Dendrite Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional solid electrolytes in lithium-ion batteries suffer from defects, grain boundaries, and inhomogeneities that lead to lithium dendrite formation, limiting their commercial application and battery performance.
Innovation Solution
A composition of A·(LiBH4)·B·(LiX)·C·(LiNH2), where X is fluorine, bromine, chloride, or iodine, is used as a solid electrolyte separator in lithium-ion batteries, which is applied through various methods such as drop-casting, spraying, or dip-coating to form thin films, reducing defects and enhancing battery performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Weight of stationary object
If conventional solid electrolytes are used as separators, then battery weight and volume are reduced, but lithium dendrite formation occurs due to defects and inhomogeneities
Solution Approach 1:
The patent uses a composite structure consisting of a porous substrate (providing mechanical strength and defect tolerance) combined with a dense coating layer of solid electrolyte material (providing high ionic conductivity and dendrite resistance). This composite approach allows the separator to maintain low weight while preventing lithium dendrite formation through the synergistic combination of porous support and dense functional layer.
Solution Approach 2:
The patent applies a dense coating layer specifically on the surfaces and within the pore structures of the porous substrate, creating local regions of high ionic conductivity and defect-free structure where lithium ion transport occurs. This localized enhancement of material quality prevents dendrite formation at critical interfaces without requiring the entire separator to be uniformly dense, thus maintaining low weight.
2Reliability
If solid electrolyte coatings are applied to passivate defects, then lithium dendrite formation is reduced, but manufacturing complexity increases
Solution Approach 1:
The patent employs a porous substrate structure that naturally provides mechanical strength and flexibility while allowing for simple coating application. The porous structure acts as a pre-formed scaffold that requires minimal additional processing to achieve the dense surface layer, reducing manufacturing complexity compared to attempting to create dense structures from scratch.
Solution Approach 2:
The patent utilizes liquid or slurry形式的 coating materials that can be applied through simple dip-coating, spray-coating, or inkjet printing techniques. These fluid-based application methods are inherently simpler than solid-state assembly processes, allowing the dense coating layer to be deposited into the porous substrate structure with minimal equipment and processing steps.
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 the A·(LiBH4)·B·(LiX)·C·(LiNH2) composition effectively passivates defects in solid separators, reducing lithium dendrite formation and improving the stability and longevity of lithium-ion batteries by enhancing ionic conductivity and minimizing reactions with the anode.
Implementation Method 1
An electrolyte physically separates and electrically insulates the positive and negative electrodes while also providing a conduction medium for Li+ ions
Implementation Method 2
a thin film composites of a lithium-stuffed garnet with a material which passivates sites on the lithium-stuffed garnet from forming lithium dendrites
Data Source
AI summary
Set forth herein are compositions comprising A·(LiBH4)·B·(LiX)·C·(LiNH2), wherein X is fluorine, bromine, chloride, iodine, or a combination thereof, and wherein 0.1≤A≤3, 0.1≤13≤4, and 0≤C≤9 that are suitable for use as solid electrolyte separators in lithium electrochemical devices. Also set forth herein are methods of making A·(LiBH4)·B·(LiX)·C·(LiNH2) compositions. Also disclosed herein are electrochemical devices which incorporate A·(LiBH4)·B·(LiX)·C·(LiNH2) compositions and other materials.