Non-aqueous Electrolyte Solution for Lithium Battery Gas Suppression

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Non-aqueous electrolyte solution batteries face issues with gas generation, deteriorated cycle characteristics at low temperatures, and decreased performance under continuous charging and high-temperature storage conditions, particularly when using cyclic carbonic ester compounds and fluorine-containing ether compounds.

Innovation Solution

A non-aqueous electrolyte solution comprising a lithium salt, a cyclic carbonate compound with unsaturated bonds, and specific compounds (I, II, or III) that inhibit gas generation and improve cycle characteristics, allowing for high-temperature storage and continuous charging performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If pressure is applied to the active material layer of the electrode to increase its density, then battery capacity is improved, but internal pressure increases remarkably when gas is generated

Engineering Contradiction:

Improvebattery capacityVSAvoidinternal pressure

Core Design Contradiction:

Quantity of substanceVSStress or pressure

Solution Approach 1:

A cyclic carboxylate compound is introduced as an intermediary substance in the electrolyte solution to react with and suppress the decomposition of the non-aqueous solvent. This mediator prevents harmful gas generation at the electrode-electrolyte interface, thereby controlling internal pressure while maintaining high battery capacity through dense active material packing.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If the battery is continuously charged to compensate for self discharging, then battery availability is improved, but gas generation increases due to electrolyte decomposition

Engineering Contradiction:

Improvebattery availabilityVSAvoidgas generation

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The cyclic carboxylate compound is preliminarily added to the electrolyte solution to form a protective film on the electrode surface before continuous charging begins. This preliminary protective layer prevents subsequent electrolyte decomposition and gas generation during prolonged charging operations, maintaining battery availability without harmful gas accumulation.

Inventive Principle:

Principle #10Preliminary action

3Duration of action of stationary object

If cyclic carbonic ester compound is used to improve storage characteristics, then cycle characteristics are improved, but gas generation increases under continuous charging

Engineering Contradiction:

Improvestorage characteristicsVSAvoidgas generation

Core Design Contradiction:

Duration of action of stationary objectVSObject-generated harmful factors

Solution Approach 1:

The electrolyte solution uses a composite formulation combining cyclic carbonic ester compound with cyclic carboxylate compound. The cyclic carbonic ester provides good storage characteristics and cycle life, while the cyclic carboxylate compound suppresses gas generation during continuous charging by preventing electrolyte decomposition, achieving both benefits simultaneously.

Inventive Principle:

Principle #40Composite materials

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 effectively reduces gas generation, maintains high cycle characteristics, and enhances battery performance under continuous charging and high-temperature conditions, enabling smaller battery sizes with improved capacity and stability.

Implementation Method 1

the cyclic carbonic ester compound having double bonds preferentially reacts with a negative electrode to form a coating of good quality over the negative electrode surface

Methodology Applied

Scientific EffectElectrochemical reaction:

Implementation Method 2

non-aqueous electrolyte solution batteries, such as lithium secondary batteries

Methodology Applied

Scientific EffectIon conduction: Conduction (electrical)

Implementation Method 3

the compound covers active spots on the positive electrode surface, oxidative decomposition of a non-aqueous solvent contained in the electrolyte solution can be inhibited

Methodology Applied

Scientific EffectAdsorption: Adsorption

Data Source

PatentUS8007938B2Nonaqueous electrolyte solution and lithium secondary battery using same

Publication Date: 2011.08.30 MU IONIC SOLUTIONS CORP

AI summary

A non-aqueous electrolyte solution is provided that realizes a large capacity, exhibits high storage characteristics and cycle characteristics, and is capable of inhibiting gas generation. The non-aqueous electrolyte solution comprises a lithium salt; at least one non-aqueous solvent selected from the group consisting of a chain carbonate, a cyclic carbonate, a chain carboxylic acid ester, a cyclic carboxylic acid ester, a chain ether, and a cyclic ether; and a compound expressed by the following formula (II)awherein R41-R52 independently of each other, represent a hydrogen atom, an alkyl group having 1-12 carbon atoms that may be substituted by a fluorine atom, an alkenyl group having 1-12 carbon atoms that may be substituted by a fluorine atom, an aryl group having 6-12 carbon atoms that may be substituted by a fluorine atom, or an aralkyl group having 7-12 carbon atoms that may be substituted by a fluorine atom, wherein each group R41-R52 may have an ether linkage in its chain, and R41 may be linked with R42, and R43 may be linked with R44, to form a ring, said ring optionally comprising an oxygen atom.