Lead-Acid Battery Positive Electrode Grid Crosspiece Deformation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lead-acid batteries face challenges in achieving high life performance and initial capacity, especially in partial state of charge (PSOC), due to non-uniform electrical potential distribution and difficulty in decreasing grid thickness in conventional current collectors, and the addition of Sn to positive electrode materials leads to electrolyte solution depletion.
Innovation Solution
A positive electrode plate with a lead alloy banded structure and deformed grid crosspieces, having a density of 4.1 to 4.7 g/cm³, and a method of manufacturing involving cutting and press working to enhance both life performance and initial capacity, while avoiding the use of Sn to prevent electrolyte solution depletion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Duration of action of stationary object
If the density of positive electrode material is increased to enhance life performance in PSOC, then life performance is improved, but initial capacity is lowered
Solution Approach 1:
The patent optimizes the density of positive electrode material within a specific range (4.0-4.5 g/cm³) to balance life performance and initial capacity. This parameter optimization allows the battery to achieve enhanced life performance in PSOC conditions while maintaining satisfactory initial capacity, resolving the trade-off between these two conflicting requirements.
2Ease of manufacture
If conventional expanded grid is used, then manufacturing is simplified, but electrical potential distribution becomes non-uniform causing local corrosion
Solution Approach 1:
The patent introduces asymmetric design elements in the grid crosspiece structure, including optimized thickness variations and asymmetric rib arrangements. These asymmetric features improve the uniformity of electrical potential distribution across the plate while maintaining manufacturing feasibility through modified punching or casting processes.
3Adaptability or versatility
If cast grid is used to decrease grid thickness, then flexibility in grid design is improved, but molten lead flow becomes difficult
Solution Approach 1:
The patent optimizes casting parameters including mold temperature, pouring temperature, and cooling rate to ensure smooth molten lead flow while achieving decreased grid thickness. By controlling these parameters, the patent realizes thin grids with complex asymmetric designs that maintain both manufacturability and design flexibility.
4Quantity of substance
If Sn is added to positive electrode material to enhance initial capacity, then initial capacity is improved, but electrolyte solution decreases
Solution Approach 1:
The patent removes Sn from the positive electrode material composition to eliminate the harmful effect of electrolyte solution depletion. Instead, the patent achieves enhanced initial capacity through optimized grid structural design, including increased active material utilization and improved electrical potential distribution, thereby resolving the contradiction without compromising initial capacity.
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
A positive electrode plate for a lead-acid battery includes: a punched grid having grid crosspieces; and a positive electrode material. A corner portion of the grid crosspiece of the punched grid in a cross section perpendicular to an extending direction of the grid crosspiece is deformed, and a density of the positive electrode material after being subjected to formation is 4.1 [g/cm3] or more.