Lead-Acid Separator Structure for Low Resistance and Puncture Strength

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing lead acid battery separators face challenges in achieving reduced electrical resistance, increased puncture strength, improved cross-machine direction stiffness, enhanced oxidation resistance, and lower basis weight, which affect battery performance and longevity.

Innovation Solution

Development of a lead acid battery separator with reduced thickness, increased puncture strength, improved CMD stiffness, and enhanced oxidation resistance, incorporating performance-enhancing additives and coatings, and a porous membrane structure with specific rib patterns.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If separator thickness is reduced to lower basis weight and improve charge acceptance, then electrical resistance decreases and charge acceptance improves, but puncture strength and mechanical durability worsen

Engineering Contradiction:
Improvecharge acceptanceVSAvoidpuncture strength
Core Design Contradiction:
Use of energy by moving objectVSStrength

Solution Approach 1:

The separator uses a composite structure combining a polyolefin base matrix with dispersed inorganic particles (such as silica, alumina, or titania) to achieve reduced thickness while maintaining enhanced puncture strength and mechanical durability through the synergistic properties of the composite material system

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The separator incorporates localized reinforcement features including rib structures with specific thickness variations and inorganic particle concentrations at critical stress points, allowing thin overall design while maintaining strength where needed

Inventive Principle:
Principle #3Local quality

2Use of energy by moving object

If separator thickness is reduced to improve charge acceptance, then electrical resistance decreases, but oxidation resistance and structural stability worsen

Engineering Contradiction:
Improvecharge acceptanceVSAvoidoxidation resistance
Core Design Contradiction:
Use of energy by moving objectVSReliability

Solution Approach 1:

The separator employs controlled addition of antioxidants and stabilizers, along with modification of polymer molecular weight and cross-linking density, to enhance oxidation resistance while maintaining reduced thickness for improved charge acceptance

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

Inorganic particles such as titania or alumina are incorporated into the polyolefin matrix to provide enhanced oxidation resistance and structural stability despite the reduced separator thickness

Inventive Principle:
Principle #40Composite materials

3Ease of manufacture

If basis weight is lowered to reduce manufacturing cost, then material consumption decreases, but mechanical strength and durability worsen

Engineering Contradiction:
Improvemanufacturing costVSAvoidmechanical strength
Core Design Contradiction:
Ease of manufactureVSStrength

Solution Approach 1:

The separator uses a polyolefin base material reinforced with dispersed inorganic particles to achieve lower basis weight and reduced material consumption while maintaining enhanced mechanical strength through the composite structure

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The separator incorporates localized rib structures with varying thickness and inorganic particle concentrations to provide mechanical strength where needed while minimizing overall material usage for cost reduction

Inventive Principle:
Principle #3Local quality

4Use of energy by moving object

If separator is made thinner to improve charge acceptance, then electrical resistance decreases, but manufacturing precision and quality control worsen

Engineering Contradiction:
Improvecharge acceptanceVSAvoidquality control
Core Design Contradiction:
Use of energy by moving objectVSManufacturing precision

Solution Approach 1:

The separator employs controlled addition of processing aids and plasticizers to improve manufacturability of thin sections while maintaining consistent thickness and quality through optimized extrusion and calendering parameters

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The composite structure with inorganic particles provides inherent dimensional stability and uniformity that facilitates precise manufacturing and quality control of thin separator designs

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 improved separator reduces electrical resistance, maintains consistent end-of-charge current, decreases grid corrosion, and extends battery life by minimizing antimony poisoning and water loss, while maintaining efficient charge acceptance and voltage control.

Implementation Method 1

pores contribute to ionic diffusion between electrodes

Methodology Applied
Scientific EffectIonic diffusion: Diffusion

Implementation Method 2

a non-conducting polymeric network prevents electronic shorting

Methodology Applied
Scientific EffectElectrical resistance: Electrical Resistance

Data Source

PatentEP3602653B1Lead acid separator, lead acid battery and vehicle
Publication Date: 2025.07.02 DARAMIC LLC
  • EP3602653B1 patent drawingFigure 1~2
  • EP3602653B1 patent drawingFigure 3A~3C
  • EP3602653B1 patent drawingFigure 4A~4C

AI summary

A separator is provided with a novel construction and/ or a combination of improved properties. Batteries, methods, and systems associated therewith are also provided. In certain embodiments, novel or improved separators, battery separators, enhanced flooded battery separators, batteries, cells, and/ or methods of manufacture and/ or use of such separators, battery separators, enhanced flooded battery separators, cells, and/ or batteries are provided. In addition, there is disclosed herein methods, systems, and battery separators having a reduced ER, improved puncture strength, improved separator CMD stiffness, improved oxidation resistance, reduced separator thickness, reduced basis weight, and any combination thereof. In accordance with at least certain embodiments, separators are provided in battery applications for flat-plate batteries, tubular batteries, vehicle SLI, and HEV ISS applications, deep cycle applications, golf car or golf cart, and e-rickshaw batteries, batteries operating in a partial state of charge ("PSOC"), inverter batteries; and storage batteries for renewable energy sources, and any combination thereof.