Separator-Free Solid-State Battery Electrolyte for Lower Interface Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing solid state electrolyte rechargeable batteries face challenges with high particle interface resistance between positive and negative active materials, significant temperature dependence, and safety concerns during short circuits, particularly when using composite polymer electrolytes without separators.
Innovation Solution
A solid state electrolyte rechargeable battery design that eliminates the need for a separator by using a conductive polymer electrolyte layer comprising an inorganic solid electrolyte and a polymer electrolyte composition, specifically a combination of graft polymerized or living radical polymerized molten salt monomers with onium cations and halogen-containing anions, along with a polyether polymer, to reduce interface resistance and enhance temperature stability and safety.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a composite polymer electrolyte composition is used without a separator, then the device complexity is reduced, but the particle interface resistance between positive and negative active materials increases
Solution Approach 1:
The patent merges the separator function and electrolyte function into a single integrated layer. The conductive polymer electrolyte layer serves both as the ionic conductor and as the separator between electrodes, eliminating the need for a separate porous separator component. This integration reduces device complexity while maintaining effective ion transport between electrodes.
Solution Approach 2:
The patent modifies the electrical conductivity parameter of the polymer electrolyte by incorporating conductive polymers and optimizing the molten salt concentration. This parameter change enables the electrolyte layer to function effectively as both electrolyte and separator, reducing interface resistance without requiring additional separator components.
2Ease of manufacture
If polyether polymer is used as electrolyte, then the ease of manufacture is improved, but the temperature dependence increases and low temperature property deteriorates
Solution Approach 1:
The patent creates a composite electrolyte system combining polyether polymer with conductive polymer components and molten salts. This composite structure leverages the manufacturing ease of polyether while the conductive polymer and molten salt additives improve temperature performance by providing alternative ion conduction pathways that remain effective at lower temperatures.
Solution Approach 2:
The patent introduces regions of high ionic conductivity within the polyether matrix through localized incorporation of molten salts and conductive polymer segments. These localized conductive regions provide temperature-resilient ion transport pathways while maintaining the overall polyether structure's manufacturing advantages.
3Reliability
If Garnet solid inorganic electrolyte is used, then the reliability is improved, but the manufacturing precision requirement increases due to excessive loading process
Solution Approach 1:
The patent introduces a polyether polymer layer as an intermediary between the Garnet inorganic electrolyte particles and the electrodes. This intermediary layer simplifies the manufacturing process by eliminating the need for precise particle packing and sintering, while still enabling effective ion transport through the Garnet particles.
Solution Approach 2:
The patent changes the physical state parameter of the electrolyte system from fully rigid sintered inorganic electrolyte to a semi-flexible composite with polyether binder. This parameter change allows for more tolerant manufacturing processes that do not require precise particle interface control, while maintaining the high reliability benefits of Garnet electrolyte.
4Reliability
If physical processing such as electrode crimping is applied to reduce particle interface resistance, then the conductivity is improved, but the device complexity increases
Solution Approach 1:
The patent incorporates conductive polymer components and molten salts into the electrolyte layer during the initial electrolyte formation process, before electrode assembly. This preliminary action pre-establishes high-conductivity pathways at potential particle interfaces, eliminating the need for subsequent electrode crimping or other physical processing steps to improve conductivity.
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 solution achieves a significant reduction in particle interface resistance, minimal temperature dependence, and improved safety during short circuits, enabling a thinner battery design with enhanced REDOX resistance, particularly when using lithium metal foil as the negative electrode.
Implementation Method 1
a solid state electrolyte layer which is a composition comprising an inorganic solid electrolyte and a polymer electrolyte composition
Implementation Method 2
a polymer electrolyte composition wherein the polymer electrolyte composition is selected from the group consisting of a polymer electrolyte composition (X1) obtained by graft polymerizing or living radical polymerization
Data Source
AI summary
Solid state solid electrolyte rechargeable battery in no use of separator comprising a positive electrode/a conductive polymer solid state electrolyte layer/a negative electrode in which the solid state electrolyte layer is a composition comprising an inorganic solid electrolyte and a polymer electrolyte composition wherein the polymer electrolyte composition is selected from the group consisting of a polymer electrolyte composition (X1) obtained by graft polymerizing or living radical polymerization of a molten salt monomer having a polymerizable functional group and having an onium cation and an anion containing a halogen with a fluoro polymer, and a polymer electrolyte composition comprising (X1) and at least one kind selected from the following (X2) and (X3),X2: a molten salt having an onium cation and an anion containing a halogen, or a molten salt monomer having a polymerizable functional group and having an onium cation,X3: a polymer or copolymer of a molten salt monomer having a polymerizable functional group and having an onium cation.By providing this rechargeable battery, the solid electrolyte rechargeable battery without separator which has a descending effect of particle interface resistance between a positive and negative active materials in case of using conductive polymer solid electrolyte, a thin film cell, a less dependence on the temperature and excellent safety in case of happening short circuit can be obtained.