I actually wanted to try the Pottasiumsulfide!
Seems nobody have tried this on (any?) forum, so I want to take the risk/experiment with it!
So I bought some K2S for my batteries. (it's not that expensive)
Will try the 0,4 value, which seems to give the best results. (See figure 8 in the paper)
The hydrogen generation is really the only downside I can find about the Nickel-Iron chemistry (at least, the only downside,
that actually matters in day to day usage: watering) (forget about size, self discharge doesn't really matter at all)
I will try ONE battery at first, just as a precaution.
I for one am extremely curious as to how well this battery material works out.
Today, all the hype is based on Lithium-Ion batteries which are great for lightweight and mobile applications. But for stationary purposes, who cares about weight? You might be on to something and I eagerly await your findings.
I measured the desired quantity (in the check sheet above)
Then I pulled back some elektrolyte and dissolved the K²S in it. I does dissolve a bit like the LiOh powder.
(needs a bit of work). Then I poured in into the first battery.
The good news is: battery still works fine.
I have just ran one charge/discharge cycle.
I am not totally sure how we compare the modified elektrolyte to the other 19 batteries.
We can measure discharge voltage and charge voltage. Measuring hydrogen generation is another matter. (finger on vent hole?
balloon across cap?) Water consumption would also be an indicator.
I think I'l first let it run for a few charge/discharge cycles.
I might have added too little?
Quote from the paper:
it is usually encounter with most NiFe electrolyte systems at a concentration close to 0.1 M
0.1M = 20mg ? (what most manufacturers recommend, including mine: Henan Hengming)
Will do half of the battery bank.
Then wait & see. and then double the concentration if too little effect.
The first battery (done saterday 29/5) continues to work fine.
I would say it's voltage is slightly higher then the rest. But it's too soon to draw a conclusion I think.
There are always some small variations.