Inorganic Particle Layer for Nonaqueous Battery Gas Management

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Nonaqueous secondary batteries experience increased internal resistance and gas generation during high-temperature charged storage when using a nitrile group-containing compound, which can lead to reduced capacity and safety concerns.

Innovation Solution

Forming an inorganic particle layer between the positive electrode plate and the separator in a nonaqueous electrolyte secondary battery to trap decomposition products of the nitrile group-containing compound, preventing them from reaching the negative electrode and thus reducing gas generation and internal resistance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a nitrile group-containing compound is added to the nonaqueous electrolyte to improve cycling characteristics and high-temperature charged storage characteristics, then the battery capacity and charge-discharge cycling are improved, but gas generation and internal resistance increase during high-temperature charged storage

Engineering Contradiction:
Improvehigh-temperature charged storage characteristicsVSAvoidgas generation
Core Design Contradiction:
ReliabilityVSObject-generated harmful factors

Solution Approach 1:

A porous layer containing inorganic particles is introduced as an intermediary between the positive electrode and the electrolyte. This porous layer traps the decomposition products (gas) generated by the nitrile group-containing compound, preventing them from accumulating and causing harmful effects while allowing the nitrile compound to continue improving cycling characteristics.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The invention employs a porous layer with inorganic particles that has controlled porosity to selectively trap gas decomposition products while maintaining ion transport. The porous structure allows the layer to absorb and retain the harmful gas molecules generated during high-temperature storage without blocking the electrolyte's ionic conductivity.

Inventive Principle:
Principle #31Porous materials

2Reliability

If a nitrile group-containing compound is added to the nonaqueous electrolyte to improve cycling characteristics, then the battery capacity is improved, but internal resistance increases during high-temperature charged storage

Engineering Contradiction:
Improvecycling characteristicsVSAvoidinternal resistance
Core Design Contradiction:
ReliabilityVSLoss of energy

Solution Approach 1:

The porous layer with inorganic particles acts as a mediator that captures decomposition products before they can reach the electrodes and increase internal resistance. This intermediary structure prevents the buildup of resistive layers on the electrode surfaces while preserving the beneficial cycling characteristics provided by the nitrile compound.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Reliability

If a nitrile group-containing compound is added to the nonaqueous electrolyte to improve high-temperature charged storage characteristics, then the battery capacity is improved, but decomposition products are generated that reach the negative electrode

Engineering Contradiction:
Improvehigh-temperature charged storage characteristicsVSAvoiddecomposition products reaching negative electrode
Core Design Contradiction:
ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The porous layer containing inorganic particles serves as a protective intermediary between the positive electrode (where decomposition occurs) and the negative electrode. It selectively traps the decomposition products in its porous structure, preventing them from migrating to and damaging the negative electrode while allowing the nitrile compound to function.

Inventive Principle:
Principle #24Intermediary (Mediator)

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 inorganic particle layer effectively minimizes gas generation and internal resistance increase, maintaining high residual capacity and safety during high-temperature charged storage.

Implementation Method 1

A layer of inorganic particles is formed between the positive electrode plate and the separator or between the negative electrode plate and the separator... to trap decomposition products of the nitrile group-containing compound

Methodology Applied
Scientific EffectAdsorption: Adsorption

Data Source

PatentEP2365571B1Nonaqueous electrolyte secondary battery
Publication Date: 2013.06.05 SANYO ELECTRIC CO LTD
  • EP2365571B1 patent drawingFigure 1A~1C

AI summary

To provide a nonaqueous electrolyte secondary battery with a small increase in internal resistance and less gas generation during high-temperature charged storage, and with a high residual capacity, when using a non-aqueous electrolyte containing a nitrile group-containing compound. The nonaqueous electrolyte secondary battery includes a positive electrode plate containing positive electrode active material, a negative electrode plate containing negative electrode active material, a nonaqueous electrolyte containing a nitrile group-containing compound, and a separator provided between the positive electrode plate and the negative electrode plate, and is also provided with a layer of inorganic particles between the positive electrode plate and the separator or between the negative electrode plate and the separator. It is preferable that the layer of inorganic particles be formed on a surface of the positive electrode plate.