Date: 12/11/2018 15:51:15
From: Spiny Norman
ID: 1302446
Subject: Powered by salt water

Initially I was sceptical, but it seems legit – Hydra-Light

I initially wondered why some submarines don’t use this technology to get power for the electric motors. It’d be totally silent, though I’m not sure if enough power could be generated to get any real speed out of the sub. Apparently all that’s needed to be renewed/replaced is magnesium bars as they are sacrificial in the reaction.

Anyway I thought it was interesting. It might be handy to have a battery that can sit around for twenty-five years and still be 100% usable when needed.

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Date: 12/11/2018 16:07:26
From: Michael V
ID: 1302456
Subject: re: Powered by salt water

Interesting, thanks.

:)

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Date: 12/11/2018 16:29:29
From: mollwollfumble
ID: 1302469
Subject: re: Powered by salt water

Spiny Norman said:


Initially I was sceptical, but it seems legit – Hydra-Light

I initially wondered why some submarines don’t use this technology to get power for the electric motors. It’d be totally silent, though I’m not sure if enough power could be generated to get any real speed out of the sub. Apparently all that’s needed to be renewed/replaced is magnesium bars as they are sacrificial in the reaction.

Anyway I thought it was interesting. It might be handy to have a battery that can sit around for twenty-five years and still be 100% usable when needed.

It’s an ordinary battery isn’t it? With electrodes of magnesium and carbon, and an electrolyte of salt water.

> It’s not a battery its an oxygen fuel cell (a low power generator) and to restart the cell you simply need to re-dip it again for 10 seconds.

That still makes it very like the first ever commercial battery.

“The Leclanché cell is a battery invented and patented by the French scientist Georges Leclanché in 1866. The battery contained a conducting solution (electrolyte) of ammonium chloride, a cathode (positive terminal) of carbon, a depolarizer of manganese dioxide (oxidizer), and an anode (negative terminal) of zinc (reductant). The chemistry of this cell was later successfully adapted to manufacture a dry cell.”

In the above, change “ammonium chloride” to “sodium/magnesium chloride”, change “manganese dioxide” to “dissolved oxygen”, and change “zinc” to “magnesium” to get the Hydra-Light. The use of magnesium instead of zinc means that it doesn’t last nearly as long. The use of dissolved oxygen rather than manganese dioxide means that it lasts an even shorter time.

The only use I can see for it is in an emergency SOS broadcasting device or alarm on a yacht. Automatically comes on if submerged. It wouldn’t last long enough for anything else.

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Date: 12/11/2018 16:58:55
From: mollwollfumble
ID: 1302485
Subject: re: Powered by salt water

Spiny Norman said:


Initially I was sceptical, but it seems legit – Hydra-Light

I initially wondered why some submarines don’t use this technology to get power for the electric motors. It’d be totally silent, though I’m not sure if enough power could be generated to get any real speed out of the sub. Apparently all that’s needed to be renewed/replaced is magnesium bars as they are sacrificial in the reaction.

Anyway I thought it was interesting. It might be handy to have a battery that can sit around for twenty-five years and still be 100% usable when needed.

Don’t bank on it being 100% usable after 25 years. Magnesium metal corrodes really rapidly when exposed to ambient air. Ambient air contains oxygen, salt and water, conditions necessary for rapidly degrading the magnesium.

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Date: 12/11/2018 21:36:26
From: dv
ID: 1302598
Subject: re: Powered by salt water

What mollwolfumble said. Going by the FAQ on the site, it’s a magnesium-carbon cell. Magnesium is depleted when you run it. It’s not rechargeable.

Product FAQ’s.

Q: How does it work?

A: Dip the hydra-cell for approx. 10-15 seconds in any water, this causes a chemical reaction between magnesium and oxygen, inducing an ionic exchange releasing electrons (power), which are then collected by the carbon cathode collector and converted into power.

Q:How long does one cell last?

A. One cell will give you roughly 200+ hours of power. That means 200+ hours of turned on light time.

Q: When does the power output stop?

A: From new until the magnesium rod is needle thin there’s a linear power output (same power until the rod has been consumed). The cell is exhausted when the Anode is fully depleted

Q: How do I recharge the battery?

A: It’s not a battery its an oxygen fuel cell (a low power generator) and to restart the cell you simply need to re-dip it again for 10 seconds. (Until the consumable Anode is depleted)

—-

https://www.hydralight.com.au/shop-faqs/

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Date: 12/11/2018 22:21:27
From: Spiny Norman
ID: 1302612
Subject: re: Powered by salt water

Okay thanks for that info chaps.
It’s why I keep you on as my science advisers.

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