Provide a short description of your setup. Did you use something that may have contaminated the electrolyte, for example exposed copper wire partially immerged during charging/discharging?
@@CinzLab i use 6 M KOH and 0.2 M zinc acetate as the electrolyte. zinc foil as the negative electrode, carbon paper as the positive electrode, and the battery like this website www.advancedsciencenews.com/new-air-electrodes-zinc-air-batteries/ There is no other metal in the battery except zinc.
@wayne In the electrolyte should be present mostly zincate ions and some zinc oxide and zinc hydroxide as byproduct. All of them should be colorless however. What about the yellow color? Does it appear in the discharging process or after the discharging/charging sequence? At the moment I'm thinking about an acetate byproduct, as far as you have an organic component in a strongly caustic solution, that could someway decompose it in a sort of long term side-reaction. Do you observe the same phenomenon also without using zinc acetate?
CinzLab During charging and discharging, yellow will be slowly produced, and the color will become deeper and deeper. However, zinc acetate is mainly used as a substance needed to provide a reversible reaction, so it must be added. What are the possible byproducts of zinc acetate?
i like the flowing water background
*That is STAINLESS-STEEL wool your using and has less than half the Oxidation potential of the cheaper IRON -WOOL that can rust!*
i have tried this ,it works but voltage goes down when i light a led.After 1minutes same , What can be wrong?
It is a normal phenomenon called "voltage drop".
@@CinzLab it can only hold 3-4 sec .it cant light lamp after 3-4 sec.
@@mp3huntertr first, provide a description of your set up
Do you know why the color of the electrolyte turns yellow after charging and discharging
Provide a short description of your setup. Did you use something that may have contaminated the electrolyte, for example exposed copper wire partially immerged during charging/discharging?
@@CinzLab i use 6 M KOH and 0.2 M zinc acetate as the electrolyte. zinc foil as the negative electrode, carbon paper as the positive electrode, and the battery like this website www.advancedsciencenews.com/new-air-electrodes-zinc-air-batteries/
There is no other metal in the battery except zinc.
@wayne In the electrolyte should be present mostly zincate ions and some zinc oxide and zinc hydroxide as byproduct. All of them should be colorless however.
What about the yellow color? Does it appear in the discharging process or after the discharging/charging sequence?
At the moment I'm thinking about an acetate byproduct, as far as you have an organic component in a strongly caustic solution, that could someway decompose it in a sort of long term side-reaction.
Do you observe the same phenomenon also without using zinc acetate?
CinzLab During charging and discharging, yellow will be slowly produced, and the color will become deeper and deeper. However, zinc acetate is mainly used as a substance needed to provide a reversible reaction, so it must be added. What are the possible byproducts of zinc acetate?
@@andy915029 what about the carbon paper? What's its composition? Does it seem damaged by the solution?