Solid-State Polymer Electrolyte for Sodium-Ion Battery Safety

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current sodium-ion batteries face challenges with liquid electrolytes, including volatility, safety concerns, and limited ionic conductivity, which hinder their widespread adoption and performance, particularly in comparison to lithium-ion batteries. Additionally, existing polymer electrolytes for solid-state batteries exhibit low mechanical performance and ionic conductivity, making them unsuitable for ambient temperature operation.

Innovation Solution

Development of an all-solid-state polymer electrolyte comprising a carbonic ester polymer, a sodium or lithium salt, and a porous support material, with specific conductivity and electrochemical window ranges, to enhance ionic conductivity and mechanical strength, suitable for sodium and lithium batteries.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If liquid electrolyte is used in sodium-ion battery, then ionic conductivity is achieved, but safety deteriorates due to volatility and decomposition

Engineering Contradiction:
ImprovesafetyVSAvoidvolatility and decomposition
Core Design Contradiction:
ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The patent changes the physical state of the electrolyte from liquid to solid polymer form, fundamentally altering the parameter of phase state to eliminate volatility and decomposition issues while maintaining ionic conductivity through polymer chain motion and ion transport mechanisms

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent employs composite polymer electrolyte materials combining multiple polymer components and additives to achieve both safety (inherent solid-state stability) and ionic conductivity (through optimized composite structure and ion transport pathways)

Inventive Principle:
Principle #40Composite materials

2Reliability

If conventional polymer electrolyte is used in solid-state battery, then safety is improved, but mechanical performance deteriorates

Engineering Contradiction:
ImprovesafetyVSAvoidmechanical performance
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The patent creates composite polymer electrolyte systems combining polymers with different mechanical properties and reinforcement agents to achieve both adequate mechanical strength for structural integrity and ionic conductivity for electrochemical performance

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The patent develops thin-film polymer electrolyte structures that provide sufficient mechanical strength and dimensional stability while maintaining flexibility and ionic transport pathways, effectively serving as both structural and functional components

Inventive Principle:
Principle #30Flexible shells and thin films

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 provides sodium batteries with improved rate capability, cycling stability, and safety, while being cost-effective and environmentally friendly, and effectively suppresses lithium dendrite growth, enhancing the performance and safety of lithium batteries.

Implementation Method 1

the body material of the electrolyte is a carbonic ester polymer... high ionic conductivity

Methodology Applied
Scientific EffectIon transport: Conduction (electrical)

Implementation Method 2

a porous support material... mechanical strength

Methodology Applied
Scientific EffectMechanical support:

Implementation Method 3

effectively suppresses lithium dendrite growth

Methodology Applied
Scientific EffectDendrite suppression:

Data Source

PatentEP3258532B1All-solid-state polymer electrolyte, and preparation and application thereof
Publication Date: 2020.12.16 QINGDAO INST OF BIOENERGY & BIOPROCESS TECH CHINESE ACADEMY OF SCI
  • EP3258532B1 patent drawingFigure 1~3
  • EP3258532B1 patent drawingFigure 4~5
  • EP3258532B1 patent drawingFigure 6

AI summary

The present invention relates to battery technologies, and specifically to a solid-state polymer electrolyte, and preparation and application thereof. The electrolyte comprises a carbonic ester polymer, a metal salt and a porous support material; wherein the thickness is 20 µm- 800 µm; the ionic conductivity is 2×10-5 S/cm - 1×10-3 S/cm; the electrochemical window is higher than 3.6 V; and the metal salt is a sodium salt or a lithium salt. The preparation comprises: dissolving the polymer and the metal in a certain proportion in solvent; preparing a film on the porous support material; and obtaining a solid-state polymer electrolyte material by vacuum drying. The solid-state battery assembled by the present invention has better rate capability and superior cycling stability; no electrolyte is added, thus having high security; a body material is polymer, thus having cheap prices and low costs; and the solid-state polymer electrolyte material is easy to prepare.