Lead-Acid Battery Separator Ribs for Electrolyte Stratification Control

Solution Overview

Problem

Lead acid batteries in micro-hybrid systems face challenges with electrolyte stratification due to idling stop operations, leading to unreliable charge monitoring and reduced battery life, as conventional separators fail to effectively manage electrolyte movement and concentration differences.

Innovation Solution

A separator for lead acid batteries featuring a porous backweb with broken ribs on both surfaces, specifically designed to inhibit the downward movement of sulfuric acid by arranging ribs with unique shapes and orientations that prevent linear sedimentation, promoting zigzag movement and reducing stratification.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional separators are used in lead acid batteries for micro-hybrid systems, then the battery structure is simple and manufacturing is easy, but electrolyte stratification occurs due to idling stop operations, leading to unreliable charge monitoring and reduced battery life

Engineering Contradiction:

Improvebattery reliabilityVSAvoidseparator structure complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The separator is divided into multiple sections with different rib configurations. The first section has ribs extending from both surfaces to control electrolyte flow, while the second section has ribs extending from only one surface. This segmentation allows different regions of the separator to perform specialized functions in managing electrolyte stratification.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the separator are designed with different rib structures tailored to local requirements. The first section uses a dual-surface rib configuration to address stratification in the upper portion of the battery, while the second section uses a single-surface configuration for the lower portion, optimizing electrolyte flow control at each location.

Inventive Principle:

Principle #3Local quality

2Reliability

If the separator uses a simple rib structure, then manufacturing is easier and device complexity is lower, but it fails to effectively control electrolyte movement and prevent stratification

Engineering Contradiction:

Improvecharge monitoring reliabilityVSAvoidseparator manufacturing complexity

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The separator is divided into multiple sections with different rib configurations. The first section has ribs extending from both surfaces to control electrolyte flow, while the second section has ribs extending from only one surface. This segmentation allows different regions of the separator to perform specialized functions in managing electrolyte stratification.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the separator are designed with different rib structures tailored to local requirements. The first section uses a dual-surface rib configuration to address stratification in the upper portion of the battery, while the second section uses a single-surface configuration for the lower portion, optimizing electrolyte flow control at each location.

Inventive Principle:

Principle #3Local quality

3Productivity

If excessive charging is suppressed by idle stop operation, then fuel consumption efficiency is improved, but the amount of gas generated by electrolysis is minimized, preventing the stirring action needed to eliminate stratification

Engineering Contradiction:

Improvefuel consumption efficiencyVSAvoidbattery performance stability

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The separator's rib structure creates periodic obstacles that induce oscillatory flow patterns in the electrolyte. As electrolyte flows through the channels formed by the ribs, it experiences periodic direction changes and turbulence, which continuously mix the electrolyte and prevent stratification without requiring gas generation.

Inventive Principle:

Principle #19Periodic action

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 separator effectively suppresses electrolyte stratification, enhancing battery reliability and extending battery life by ensuring uniform electrolyte distribution and accurate charge monitoring.

Implementation Method 1

arranging ribs with unique shapes and orientations that prevent linear sedimentation, promoting zigzag movement and reducing stratification

Methodology Applied

Scientific EffectZigzag flow:

Implementation Method 2

sulfuric acid generated during charging sediments at the bottom of the battery

Methodology Applied

Scientific EffectSedimentation: Sedimentation

Implementation Method 3

a porous backweb and a plurality of ribs extending from each of both surfaces of the backweb

Methodology Applied

Scientific EffectPorosity: Porosity

Data Source

PatentUS20240120618A1Separator for lead acid battery

Publication Date: 2024.04.11 ENTEK ASIA INC

AI summary

[Problem] To provide a separator for a lead acid battery capable of suppressing electrolyte stratification and improving the battery reliability (prolongation of life during idling stop operation and stability of capacity detection) of a lead acid battery.[Solution] A separator for a lead acid battery, characterized in that the separator comprises a porous backweb and a plurality of ribs extending from each of both surfaces of the backweb, the rib on a surface on a side that comes into contact with a positive electrode plate is a broken rib, has a shape with two or more bending points, and is a linear broken rib that bends in opposite directions at each of two consecutive bending points or is a curved broken rib having one or more inflection points.