Lead Acid Battery Negative Plate Nonwoven Fabric Separator
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Flooded-type lead acid batteries used in partially charged states experience shortened lifetimes due to the formation of electrolyte layers, which hinder charging and discharging reactions, especially in idling-stop system vehicles where the battery is frequently partially charged and difficult to stir.
Innovation Solution
A flooded-type lead acid battery design featuring a negative plate with a nonwoven fabric contact on its surface and an envelope separator made of a microporous synthetic resin sheet, utilizing glass, pulp, and inorganic oxide powder, prevents the precipitation of sulfuric acid ions and maintains a uniform electrolyte concentration, thereby preventing layer formation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the battery is used in partially charged state (PSOC) to improve fuel consumption in ISS vehicles, then the engine operation time is reduced and fuel efficiency is improved, but the battery lifetime is shortened due to coarse lead sulfate formation and electrolyte layering
Solution Approach 1:
The patent employs a glass fiber mat separator with porous structure that allows electrolyte penetration while preventing layer formation. The porous material facilitates ion transport and maintains electrolyte uniformity even in PSOC conditions, thereby extending battery lifetime while preserving fuel efficiency benefits
Solution Approach 2:
The invention uses a composite structure combining glass fiber mat with microporous synthetic resin envelope separator. This composite separator system effectively prevents electrolyte layering and sulfuric acid ion precipitation, resolving the contradiction between PSOC operation and battery durability
2Use of energy by moving object
If sulfuric acid ions are generated from lead sulfate during charging, then the charging reaction progresses, but the heavy sulfuric acid ions move below in electrolyte and form concentrated layers that hinder further charging
Solution Approach 1:
The patent utilizes gassing-induced electrolyte stirring during charging to prevent sulfuric acid ion sedimentation. The gas evolution creates turbulent flow that continuously mixes the electrolyte, maintaining concentration uniformity and preventing layer formation that would hinder charging progress
Solution Approach 2:
The glass fiber mat separator with its porous structure facilitates continuous electrolyte circulation and prevents localized concentration gradients. The porous material allows efficient ion transport while maintaining overall electrolyte homogeneity during charging cycles
3Use of energy by moving object
If hydrogen gas is generated from the negative plate surface during charging, then the charging process continues, but the gas does not sufficiently contribute to stirring electrolyte and layers form
Solution Approach 1:
The glass fiber mat separator enhances electrolyte stirring effectiveness by creating turbulent flow patterns as electrolyte passes through its porous structure. This improved mixing action compensates for insufficient gas-induced stirring, preventing layer formation while maintaining charging process efficiency
Solution Approach 2:
The composite separator system combining glass fiber mat with synthetic resin envelope creates enhanced fluid dynamics that improve electrolyte circulation. The combination of materials provides both structural integrity and effective stirring action, resolving the insufficiency of gas-only mixing
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
This configuration enhances the charge acceptance characteristics and extends the battery's lifetime by maintaining a uniform electrolyte distribution and preventing layer formation, even under partially charged conditions.
Implementation Method 1
sulfuric acid ions are heavy. Thus, sulfuric acid ions tend to move below in electrolyte... the electrolyte is stirred due to gassing in the end of charging, and it is suppressed that sulfuric acid ions are moved below
Data Source
AI summary
On each negative plate (1), a non-woven fabric (2) composed of fibers of at least one material selected from a group of materials comprising glass, pulp and polyolefins comes into contact with the entire surface of the plate without being integrated with the plate. Each negative plate (1), which is in contact with the non-woven fabric (2), is contained in an envelope separator (3) comprising a microporous synthetic resin sheet, and is laminated with a positive plate (4). The non-woven fabric is manufactured through papermaking process in which glass fibers, pulp and silica powder are preferably used and dispersed in water as the main components.