Anion-Conducting Separator Membrane for Zinc-Air Battery

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing batteries face limitations such as high flammability of lithium, frequent replacement needs, and difficulties in recharging due to zinc crossover and hydrogen formation, leading to inefficient performance and short battery life.

Innovation Solution

A battery utilizing an anion-conducting polymeric composition comprising a copolymer of styrene and vinylbenzyl-Rs, where Rs is a positively charged cyclic amine group, with specific terpolymer formulations and additives to enhance conductivity and reduce ion crossover, creating a separator membrane that allows efficient hydroxyl transport while limiting zinc and copper ion transport.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If a separator membrane with high ion conductivity is used, then energy loss is reduced, but zinc crossover and hydrogen formation increase during recharging

Engineering Contradiction:

Improveenergy lossVSAvoidrecharging efficiency

Core Design Contradiction:

Loss of energyVSReliability

Solution Approach 1:

The separator membrane incorporates functional groups with different properties at different locations: negatively charged groups (sulfonate, carboxylate, phosphonate) that attract and retain zinc ions to prevent crossover, and hydrophilic groups that facilitate hydroxyl ion transport. This local differentiation allows the membrane to simultaneously reduce energy loss and prevent zinc crossover during recharging.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The separator membrane is constructed as a composite material containing multiple functional groups within the polymer structure, including negatively charged groups for ion selectivity and hydrophilic groups for conductivity. This composite approach enables the membrane to achieve both low energy loss and high recharging efficiency by balancing ion transport and ion retention functions.

Inventive Principle:

Principle #40Composite materials

2Power

If lithium ion batteries are used to achieve high energy density, then power output is improved, but flammability and replacement frequency increase

Engineering Contradiction:

Improvepower outputVSAvoidflammability

Core Design Contradiction:

PowerVSObject-affected harmful factors

Solution Approach 1:

The invention changes the chemical parameters of the battery system by using alkaline chemistry with zinc anode and air cathode instead of lithium ion chemistry. The separator membrane is specifically designed with functional groups that control ion transport in this alkaline environment, enabling safe operation without the flammability issues of lithium while maintaining acceptable power output through optimized hydroxyl ion conductivity.

Inventive Principle:

Principle #35Parameter changes

3Ease of manufacture

If conventional alkaline batteries are used to achieve reasonable energy density, then manufacturing simplicity is improved, but recharging capability deteriorates due to zinc crossover

Engineering Contradiction:

Improvemanufacturing simplicityVSAvoidrecharging capability

Core Design Contradiction:

Ease of manufactureVSDuration of action of moving object

Solution Approach 1:

The separator membrane acts as an intermediary component between the zinc anode and air cathode, using its functional groups to mediate ion transport. The negatively charged groups selectively interact with zinc ions to prevent crossover during recharging, while the hydrophilic groups facilitate necessary hydroxyl ion transport. This intermediary function enables conventional alkaline battery construction to achieve reversible recharging capability.

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 solution results in a battery with reduced energy loss, lower area-specific resistance, and improved performance by minimizing zinc crossover and hydrogen formation, enabling more efficient recharging and extended battery life.

Implementation Method 1

anion-conducting polymeric composition comprising a copolymer of styrene and vinylbenzyl-Rs, where Rs is a positively charged cyclic amine group

Methodology Applied

Scientific EffectIon conduction: Conduction (electrical)

Implementation Method 2

creating a separator membrane that allows efficient hydroxyl transport while limiting zinc and copper ion transport

Methodology Applied

Scientific EffectIon rejection: Semipermeable Membrane

Data Source

PatentUS10147974B2Battery separator membrane and battery employing same

Publication Date: 2018.12.04 GREENLYZER US INC

AI summary

A battery comprises an ion-conducting polymeric composition comprising a copolymer of styrene and vinylbenzyl-Rs, where Rs is a positively charged cyclic amine group. The ion-conducting polymeric composition can be in the form of a membrane. The ion-conducting polymeric composition can comprise a terpolymer of styrene, vinylbenzyl-Rs and vinylbenzyl-Rx, in which Rs is a positively charged cyclic amine group, Rx is at least one constituent selected from the group consisting of Cl, OH, and a reaction product between an OH or a Cl and a species other than a cyclic amine or a simple amine, the total weight of the vinylbenzyl-Rx groups is greater than 1% of the total weight of the membrane, and the total weight of the vinylbenzyl-Rs groups is 15% or more of the total weight of the membrane.