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This is understandable. When you develop a company like this, you will 100% like to focus on contracts that can guarantee you enough volume, working at the small scale makes little sense from a business perspective for a small company. This is especially the case if the margin per kg of product...

You can read the gelion patents to get a better idea about this technology. This likely works, but it is going to be quite expensive - the gels are expensive ionic liquid electrolytes - so these are unlikely to ever be able to compete against Li-ion or to be available for someone to build in a...

If I try to take this to 2000 uAh at 0.5mA the Coulombic efficiency drops to 69%, with an energy efficiency of 33.6%. Seems most of the energy is wasted when I go significantly above 1000 uAh. Given the amount of volume of electrolyte (0.1mL - 0.5M ZnBr2 + 0.2M TBAB), this implies that I am able...

No worries! I do agree that an organic chemical is an additional complexity that we better avoid if possible. If it gives worse results I'll definitely not use it.

I would like to share with you the first results of my Zn-Br batteries using TMPhABr as a sequestering agent. Seems VERY promising :) https://chemisting.com/2020/09/28/zinc-bromine-batteries-first-tests-using-tmphabr/ . Look forward to your comments!

Depends on what you're sulfonating, different organic groups can be sulfonated by different reagents. Most sulfonating agents are far worse than sulfuric acid, reagents like chlorosulfonic acid. Although very reactive organic groups, like aldehydes, can be sulfonated with mild reagents like...

I think I will work more on the chemistry before using more of my carbon materials, which I have a small supply of, because without the chemistry properly working, it is not smart to optimize the cathode choice. There are two main roads to try: Increase the solubility of the TBABr in the ZnBr2...

Thanks for letting me know Tim! It might be your phone/browser combination that the page is having issues with. Can you access it without problems from a desktop?

Also note I decided to charge the battery described in #33 to 1.3V instead of 1.35V, since upon starting the first charging cycle I noticed that the CC6P cathode has greatly increased the capacity.

It was around 160 USD including shipping via DHL. However, components might be more expensive now. Here is the information for my order in case any of it is useful for you :

This is a different device, not a flow battery but just a regular static battery. There is no membrane here. For updates on the flow battery please check out the flow battery thread!

Zn(II) will not react with hydrogen. You need metallic zinc and high temperature to produce ZnH2 from metallic Zn and hydrogen gas.

So a Zn-Br battery without a sequestering agent will deteriorate faster, basically because it is being over-charged more if you try to charge it to 15mAh since elemental Br diffusion is much more efficient. You can see the significant deterioration of the charge potential. It becomes...

These are the files. They might charge you to create a component placement file, sadly I don't have that one.

Thanks for linking that article, I have read it before, but I do believe others who haven't will find the link really useful. Given my current experience with these batteries, I now believe that this article ignores some key problematic aspects that greatly limit the usability of a minimal...

So I decided to not run this experiment, as getting long term cycling results of batteries at low current densities is not practical, it would take months to get hundreds of cycles. The lowest current that I believe is practical to gather results for me is around 2.0mA/cm2. This means I will...

Thanks for sharing! Having charge/discharge curves that plot voltage as a function of the injected/extracted charge is vital, because this allow us to determine a wide variety of important data (coulombic efficiency, energy efficiency, capacity, etc). This is the most fundamental measurement...

Sadly Sodium ion batteries require inert conditions for assembly (no water or oxygen) so I cannot do that at home.

An important point is that both NiFe and FeCl3 flow batteries are very maintenance heavy. I don't know if you have used NiFe batteries before, but periodic electrolyte changes - which involves moving and dumping large amounts of highly concentrated KOH+LiOH solutions - need to be done, often...

I mean, there are currently several published alternatives that work better than Nafion and that are purportedly "cheaper". The question is, can I buy them easily off any place like alibaba or ebay? If the answer is you can't, then they might as well not exist in the short term. You will often...

I don't think I will play with this backplated configuration anymore. It is too hard to make because basically any mistake in the entire assembly or any deterioration of the insulating coating means you will get dendrites that will short the battery. It is a very difficult to engineer approach...

I had to restart the test because of a computer issue (computer restarted in the middle of it for updates :( ). After 70 cycles of the new test the CE=95.55% and the EE=66.86%. It seems the battery is perfectly stable, after going through 100 cycles at 2mA and 100+ cycles at 5 mA, the CE and EE...

Thanks for your reply and likes! I'm glad you like to follow my progress. About your "random query", sadly I am unfamiliar with the topic you mention, so I cannot help answer your question.

I am not recirculating, this is not a Zn-Br flow battery (the wikipedia page is mainly about this type), this is a static Zn-Br battery. I use a graphite anode for zinc deposition, TMPhABr as a sequestering agent for bromine which is imbedded in a GFE-1 graphitic carbon felt cathode and an...

I just published a blog post discussing this experiment (https://chemisting.com/2020/09/19/zinc-bromine-batteries-can-we-just-put-solid-tbabr-in-there/)

Thanks for your suggestions! :) I have confirmed the effect of chloride ions to an extent. In some experiments I made, saturating 3M ZnBr2 with NaCl, I was able to increase the efficiency values of the devices (to CE = 94.37%. EE=74.60%), those curves are posted on the thread. The main...

Not that I know of. However they might contain some small amount, I haven't done any extensive analysis of the chelates. Pure Mn-EDTA is 13% Mn by weight, so if it contains any lime, it is likely not much.

I just wrote a post about the these results using TMPhABr (https://chemisting.com/2020/10/02/zinc-bromine-batteries-going-for-high-capacity-with-tmphabr/). I am now going to try to use TMPhABr in a solid layer and a ZnBr2 at 2M saturated with TMPhABr as the electrolyte to attempt to get the...

This is another post I wrote, concerning a test with PEG-200 at 6% and some air bubbles that cause problems with electrode surface area. https://chemisting.com/2020/10/31/zinc-bromine-batteries-peg-200-bubbles-and-over-potential/