Alkaline Battery Power Aluminum Alloy Anode Research

In this paper, the effect of the alloying element,heat treatment and hot rolling process on the electrochemical behaviors and anti-corrosion properties of Al anodes in alkaline solution (80℃, Na₂SnO₃+5mol/LNaOH) has been studied. The purpose of this research is to find an Al anode which not only has the good electrochemical activity and actively participate in discharge, but also has the good anti-corrosion property. The main examination techniques such as hydrogen production test,E-T curves,Tafel curves,TEM,SEM and energy spectrum have been applied to analyze the electrochemical and anti-corrosion properties of Al alloys anode in alkaline solution (80℃, Na₂SnO₃ + 5mol/L NaOH) . The results show that:1. Increasing the addition of Sn appropriately and adding moderately In element in Al anode can significantly improve the corrosion resistance and electrochemical activity of aluminum anode;2. With the solution treatment temperature increasing, the activity of aluminum anode improves gradually. But when the temperature is higher than 540℃, the effect of temperature on the activity of aluminum anode becomes very weak. The amount of hydrogen production increases overall and the corrosion current density increases gradually, the corrosion resistance decreases. Aluminum alloy anode obtainted by solution treatment at 540℃/5h has the better comprehensive property.3. When rolling at 360℃, with the pass deformation increasing, dynamic recrystallization happens step-by-step.Microstructure also continues to become uniform. The active element such as Sn,In in matrix have also gradually distributed uniformly. The lower phase segregation makes the activity of aluminum anode reduce and improves corrosion resistance. When the pass deformation increasing to 50%, the microstructure is very not uniform with large phase segregation.the overall performance of aluminum alloy suddenly greatly reduces. For 40% pass deformation treatment, the aluminum alloy has a better comprehensive performance.4. As the rolling temperature gets higher from 330℃, for the amount of 40% pass deformation, dynamic recrystallization happens step by step. The microstructure of Al alloys gradually becomes uniform and grain size becomes small, and the active elements such as Sn,In in matrix uniformly distribute. Due to reduction of phase segregation, the corrosion resistance improves. When the rolling temperature increases at 420℃, due to the fast growth of grain size increasing, the grain size increases a lot, which results in the microstructure uniformity and the distribution of alloying elements and makes the number of phase segregation increase, therefore the comprehensive performance of aluminum alloy anode reduces. At rolling temperature of 400℃, aluminum alloy has the best comprehensive performance.5. With the content of mixed rare earth increasing, the corrosion current density continuously decreases and hydrogen evolution capacity also declines, the phase segregation becomes small and distributes evenly. At the same time, the content of activity element in phase segregation significantly reduces, so the activity of aluminum alloy anode also decreases. When the content of mixed rare earth is 0.3%, the aluminum alloy anode has better comprehensive performance.