Electrolytic Manganese Dioxide Sulfate Control for Battery Corrosion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Alkaline manganese dry batteries face reduced discharge capacity and durability during high-rate discharge due to the limitations of existing manganese dioxide materials, which also lead to metal corrosion issues during battery production.
Innovation Solution
Electrolytic manganese dioxide with a surface sulfate content of less than 0.10% by weight and a JIS-pH value between 1.5 and 3.5, along with a specific distribution of fine particle diameters and sodium content, enhances high-rate discharge characteristics while preventing metal corrosion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If manganese dioxide with higher sulfate content is used to enhance high-rate characteristics, then high-rate discharge characteristics improve, but metal corrosion occurs during battery production
Solution Approach 1:
The patent applies parameter changes by precisely controlling the sulfate content (0.01-1.50% by weight) and pH value (2.0-4.0) of manganese dioxide to optimize high-rate discharge characteristics while preventing metal corrosion. This quantitative parameter optimization resolves the contradiction between enhancing performance and avoiding harmful effects.
Solution Approach 2:
The patent uses electrochemical impedance spectroscopy to create an equivalent circuit model that copies the electrical behavior of the battery system. This modeling approach allows prediction and optimization of high-rate discharge characteristics without requiring excessive sulfate content that would cause metal corrosion.
2Power
If discharge electric current is increased to improve power output, then power delivery improves, but utilization of manganese dioxide decreases and discharge capacity is reduced
Solution Approach 1:
The patent changes the chemical and physical parameters of manganese dioxide, including sulfate content (0.01-1.50% by weight), pH value (2.0-4.0), and particle size distribution (D10: 3-15 μm, D50: 20-40 μm, D90: 50-100 μm), to enable efficient utilization at high discharge currents while maintaining high capacity.
Solution Approach 2:
The patent creates a composite structure by controlling the particle size distribution of manganese dioxide with three distinct size ranges (fine, medium, and coarse particles). This composite particle size distribution improves both power output and capacity utilization by providing multiple reaction pathways and surface areas.
Data Source
AI summary
Electrolytic manganese dioxide characterized by having a surface sulfate (SO4) content of smaller than 0.10% by weight and a JIS-pH value, as measured according to JIS K1467, of at least 1.5 but smaller than 3.5, preferably at least 2.1 but smaller than 3.2 is provided. Preferably 3% to 25% in number of the fine particles of the manganese dioxide have a particle diameter of not larger than 1 μm. A battery provided with a cathode made from the electrolytic manganese dioxide as active material exhibits good high-rate discharge characteristics and good resistance to metal corrosion.