Crosslinked Polymer Solid Electrolytes for Safer Li-Ion Cells
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithium-ion batteries face safety concerns due to the use of flammable solvents, which can lead to accidents such as fires and explosions during overcharging or short-circuiting, necessitating the development of safer and more stable solid electrolyte materials.
Innovation Solution
The development of polymer solid electrolytes with urea or carbamate functional groups that enhance mechanical and electrochemical properties, including high ionic conductivity, tensile strength, and decomposition voltage, achieved through crosslinking reactions and the use of specific polymer structures and plasticizers, allowing for safer and more efficient lithium-ion batteries.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If flammable solvents (carbonate/ether) are used in lithium-ion batteries, then ionic conductivity and electrochemical performance are improved, but safety deteriorates due to fire and explosion risks during overcharging or short-circuiting
Solution Approach 1:
The patent changes the physical state of the electrolyte from liquid to solid polymer form, fundamentally altering the safety parameters while maintaining ionic conductivity through careful selection of polymer matrices (PEO, PANI, PPy) and electrolyte compositions
Solution Approach 2:
The invention uses composite polymer electrolyte systems combining multiple polymer components (e.g., PEO with PANI, or PPy with lithium salts) to achieve both high ionic conductivity and enhanced mechanical strength, eliminating flammable solvents while maintaining electrochemical performance
2Object-generated harmful factors
If solid polymer electrolytes are developed to eliminate flammable solvents, then safety is improved, but ionic conductivity and electrochemical performance may deteriorate
Solution Approach 1:
The patent optimizes parameters such as polymer molecular weight, crosslinking density, lithium salt concentration, and plasticizer content to achieve the optimal balance between mechanical strength and ionic conductivity in solid polymer electrolytes
Solution Approach 2:
The invention introduces plasticizers (e.g., succinonitrile, ethylene carbonate) as intermediary substances that facilitate ion transport between polymer chains, enhancing ionic conductivity without compromising the solid-state safety benefits
3Strength
If polymer solid electrolytes with crosslinking structures are used to enhance mechanical strength, then tensile strength and stability are improved, but manufacturing complexity increases
Solution Approach 1:
The patent incorporates crosslinkable functional groups (epoxy, vinyl, or isocyanate groups) into the polymer structure during synthesis, allowing crosslinking to occur in-situ during battery assembly or initial charging cycles, rather than requiring separate complex crosslinking equipment
Solution Approach 2:
The invention employs self-crosslinking mechanisms where the polymer electrolyte undergoes crosslinking reactions autonomously under battery operating conditions (temperature, humidity, or electrical bias), eliminating the need for external crosslinking equipment and simplifying manufacturing
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 polymer solid electrolytes exhibit improved ionic conductivity, mechanical strength, and stability, leading to safer and longer-life lithium-ion batteries with enhanced charging/discharging rates and higher voltage capabilities, while eliminating the risks associated with flammable solvents.
Implementation Method 1
a polymer comprising a product of a crosslinking reaction including a polymer selected from the group consisting of
Implementation Method 2
various polymer solid electrolyte materials suitable for electrochemical devices such as batteries, capacitors, sensors
Data Source
Figure 1
Figure 2
Figure 3A~3G
AI summary
The present invention generally relates to various polymer solid electrolyte materials suitable for various electrochemical devices and method of making the same. Certain embodiments of the invention are generally directed to solid electrolytes having relatively high ionic conductivity and other mechanical or electrical properties, e.g., tensile strength or decomposition potential. Certain aspects include a polymer, a plasticizer, and an electrolyte salt. In some cases, the polymer may exhibit certain structures such as: ,where R1 can be one of the following groups: where n is an integer between 1 and 10000, m is a integer between 1 and 5000, and R2 to R6 can each independently be one of the following structures: