Archive of the former Yahoo!Groups mailing list: Homebrew PCBs

RE:
Just because you find articles on the Internet, that’s not a proof of good engineering practices.
There is a lot of garbage in the Internet, but there is also a lot of good stuff. It is just not easy to find the right ones.


I do agree that the internet is full of lots of unworthy projects described in detail.
BUT
I built a radio for $7 that heard France CW ... and I would NEVER have done that if I
had not sumbled across HOW to do that on the internet.

So
finding this battery article and asking the chemistry questions is just my way of
getting a few opinions and hopefully some facts or suggestions HOW to build a
battery that can actually be used to run a tube radio using readily available and
not so exotic materials.
  

 

Hi Rob,

Beside having fun experimenting, what would be the use of such awfully low performance battery? the article claims high internal resistance and 0.25V capabilty.

It looks like this battery uses zinc and copper ions to work. I think that there are other ways to make a much better battery with these parameters. But picking those two metallic ions does not explain the low voltage of said battery.
According to the website at http://www.engineeringtoolbox.com/electrode-potential-d_482.html, Zinc potential is -0.76V and Copper is +0.34V, so a good battery with those elements should have a max of 1.1V, with an average probably around 1V, which is a lot better than the 0.25V advertized.

Just because you find articles on the Internet, that’s not a proof of good engineering practices.
There is a lot of garbage in the Internet, but there is also a lot of good stuff. It is just not easy to find the right ones.

As a side note, you can see on the table that lithium has a potential of -3.04V, which explains why lithium ion batteries are the hot topic.

Just a few thoughts,
Jean-Paul
N1JPL

> On Jan 16, 2017, at 2:22 AM, Rob roomberg@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:
>
> what is sulfate of zinc and acidulated water and saturated copper sulfate crystals ?
> Do we have any chemists out there?
>
> I found an old time article how to make a battery and it specified
>
> sulfate of zinc and acidulated water and saturated copper sulfate crystals
>
> http://www.learnmorsecode.com/regen2/battery02.jpg
>
> The article said to use ZINC SULFATE
> or
> ACIDULATED water.
>
> So I got look up ZINC SULFATE on the web and is says we can buy 220mg zinc sulfate capsules...to eat.
> huh?!!??
> edible batteries?
>
> Zinc Sulfate (220mg) - 100 Capsules
> Zinc sulfate is an inorganic compound and dietary supplement. As a supplement it is used to treat zinc deficiency
>
>
> but hey...it did say "OR"
> and when I look up acidulated water it said
>
> wiki:
> Acidulated water is water that an acid has been added to it, usually lemon juice, lime juice or vinegar. Citric acid and ascorbic acid can also be used.
>
> Acidulated water can be made by combining 1.5 tablespoons vinegar or 3 tablespoons lemon juice.
>
> sooooo...... OK... this doesn't sound real toxic or dangerous to show and tell kids battery chemistry....
>
> AND THEN
> there is the saturated copper sulfate....
> which is readily available at th eharware store
> ROOT KILL copper sulfate pentahydrate 99%
> and instructions on the web say:
>
> First, you need a saturated copper sulfate solution so the crystals can form as the liquid evaporates. All you need to do to make the solution is to stir copper sulfate into very hot water until no more will dissolve. There are two ways to grow the crystals.Apr 26, 2014
> How To Grow Blue Copper Sulfate Crystals - Science Notes and Projects
> https://sciencenotes.org/how-to-grow-blue-copper-sulfate-crystals/
>
> OR
> just buy 10 pounds of crystals from a seed supply house for $32.
>
> So is this feasible or would parents be pissed if they knew their kids were near these chemicals?
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