Alkaline Battery Electrolyte Ratio for α-Nickel Hydroxide Utilization
Solution Overview
Problem
The utilization rate of the positive electrode active material in alkaline storage batteries is not increased by replacing β-nickel hydroxide with α-nickel hydroxide, and α-nickel hydroxide is unstable in alkaline aqueous solutions, limiting battery capacity and stability.
Innovation Solution
An alkaline storage battery design using an electrode group with α-type nickel hydroxide as the positive electrode material, a specific solution/capacity ratio of 2.7 cm³/Ah or more, and an alkaline electrolyte solution, ensuring high utilization rate and capacity density.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If α-nickel hydroxide is used as positive electrode active material, then capacity density is improved, but utilization rate does not increase and composition stability deteriorates
Solution Approach 1:
The patent changes the chemical composition parameters of α-nickel hydroxide by controlling the solid solution formation with specific metal elements (Co: 1-10 mass%, Al: 1-10 mass%, Mn: 1-10 mass%) to achieve both high capacity density and composition stability. This parameter optimization resolves the contradiction by finding the optimal compositional range that maintains structural stability while maximizing capacity.
Solution Approach 2:
The patent creates a composite material system where α-nickel hydroxide forms a solid solution with multiple metal elements (Co, Al, Mn). This composite approach enhances the intrinsic stability of α-nickel hydroxide while preserving its high capacity density, thereby resolving the contradiction between capacity improvement and stability maintenance.
2Quantity of substance
If α-nickel hydroxide is used as positive electrode active material, then capacity density is improved, but utilization rate is not increased
Solution Approach 1:
The patent optimizes the electrolyte composition parameters (NaOH concentration: 4-6 mass%, KOH concentration: 4-6 mass%) to match the modified α-nickel hydroxide electrode material. This parameter coordination enables both high capacity density and high utilization rate by improving ionic conductivity and electrochemical activity.
Solution Approach 2:
The patent introduces an optimized alkaline electrolyte solution as an intermediary that facilitates efficient charge transfer between the α-nickel hydroxide electrode and the external circuit. The specific electrolyte composition acts as a mediator that unlocks the full electrochemical potential of the electrode material, achieving high utilization rate alongside high capacity density.
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 battery achieves a high utilization rate of 120% or more for the positive electrode active material without leakage, maintaining high capacity density and stability.
Implementation Method 1
β-nickel hydroxide (β-Ni(OH)2) is oxidized to nickel oxyhydroxide (β-NiOOH) by charging, with one electron reacting with one Ni atom
Implementation Method 2
Ni(OH)2 + OH- → NiOOH + H2O + e-
Implementation Method 3
an alkaline electrolyte solution in an amount of V (cm3) where V/Ah≥2.7
Data Source
Figure 1
AI summary
[A Problem to be Solved] To increase a utilization rate of a positive electrode active material in an alkaline storage battery. [Solution] An alkaline storage battery 1 is an alkaline storage battery in which an electrode group formed by winding a positive electrode plate 3 and a negative electrode plate 4 with a separator 5 interposed therebetween is housed in an outer can together with an alkaline electrolyte solution. The positive electrode plate contains a positive electrode active material that contains nickel hydroxide. The nickel hydroxide is of an α-type. The alkaline electrolyte solution in the outer can is in an amount of V (cm3). The alkaline storage battery has a discharge capacity of Q (Ah). A solution/capacity ratio expressed by V/Q is 2.7 cm3/Ah or more.