Solid-State Li-S Battery Scaffold Design

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current lithium-ion batteries face safety concerns due to combustible organic components, degradation from reaction products at the anode and cathode interfaces, and limitations in power and energy density due to poor electrochemical stability of organic electrolytes, while solid-state lithium-sulfur batteries suffer from high interfacial impedance due to low surface area.

Innovation Solution

A solid-state battery design featuring a cathode and anode material with a solid-state electrolyte comprising a porous and dense region, where the cathode and anode materials are disposed on the porous regions, and a current collector is used, enhancing ion diffusion and reducing impedance through a tailored scaffold structure.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If lithium metal anode is used to achieve high energy density, then energy density is improved, but dendrite formation and safety issues worsen

Engineering Contradiction:
Improveenergy densityVSAvoidsafety
Core Design Contradiction:
Use of energy by moving objectVSReliability

Solution Approach 1:

A solid electrolyte is introduced as an intermediary layer between the lithium metal anode and cathode. This solid electrolyte prevents direct contact and potential short circuits between electrodes while maintaining ionic conductivity, thus enabling high energy density from lithium metal while improving safety by eliminating dendrite penetration risks associated with liquid electrolytes.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The electrolyte phase is changed from liquid to solid state. This parameter change fundamentally alters the interaction between electrolyte and lithium metal, preventing dendrite formation and electrolyte leakage while maintaining the high capacity benefits of lithium metal anodes, thereby resolving the safety- energy density contradiction.

Inventive Principle:
Principle #35Parameter changes

2Reliability

If solid-state battery technology is adopted to improve safety, then safety is improved, but manufacturing complexity increases

Engineering Contradiction:
ImprovesafetyVSAvoidmanufacturing complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent combines multiple functions into the solid electrolyte layer: it serves as both the ionic conductor and the physical separator between electrodes. This merging of functions reduces the number of separate components needed, simplifying the overall device structure and manufacturing process while maintaining safety benefits.

Inventive Principle:
Principle #5Merging (Combining)

3Ease of manufacture

If conventional battery materials are used to simplify manufacturing, then ease of manufacture is improved, but energy density and performance worsen

Engineering Contradiction:
Improveease of manufactureVSAvoidenergy density
Core Design Contradiction:
Ease of manufactureVSUse of energy by moving object

Solution Approach 1:

The patent changes the physical state parameter of the electrolyte from liquid to solid, enabling the use of lithium metal anodes which provide high energy density. While solid electrolyte processing requires specific conditions, the overall energy density improvement from using lithium metal outweighs the manufacturing complexity increase, and the solid state itself simplifies certain aspects like eliminating liquid handling infrastructure.

Inventive Principle:
Principle #35Parameter changes

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 design improves safety, stability, and energy density by eliminating polysulfide dissolution and reducing interfacial impedance, leading to higher power and energy storage capabilities and extended cycle life.

Implementation Method 1

solid electrolyte that conducts lithium ions

Methodology Applied
Scientific EffectIon conduction: Conduction (electrical)

Implementation Method 2

a first electrode, a second electrode, and a solid electrolyte that conducts lithium ions disposed between the first electrode and the second electrode

Methodology Applied
Scientific EffectElectrochemical reaction: Electrolysis

Data Source

PatentEP3384545A2Solid-state li-s batteries and methods of making same
Publication Date: 2018.10.10 UNIV OF MARYLAND

AI summary

Disclosed is a method of fabricating a battery or battery component having a solid state electrolyte. A scaffold is provided, the scaffold comprising: a dense central layer comprising a dense electrolyte material, the dense central layer having a first surface, and a second surface opposite the first surface; a first porous layer comprising a first porous electrolyte material, the first porous layer disposed on the first surface of the dense central layer, the porous electrolyte material having a first network of pores therein; wherein each of the dense electrolyte material and the first porous electrolyte material are independently selected from garnet materials. Carbon is infiltrated into the first porous layer. Sulfur is also infiltrated into the first porous layer. The battery component may be used in a variety of battery configurations.