JAW - Just Add Water Emergency batteries - Page 1
Forum section: electronics / general

author: Cozzmo
author_rank: Regular Contributor
timestamp: August 07, 2019, 08:57:06 pm
content: Saw a Facebook add for this today.

author: SiliconWizard
author_rank: Super Contributor
timestamp: August 07, 2019, 09:17:51 pm
content: Dropping JAWS!

author: Kean
author_rank: Unknown
timestamp: August 07, 2019, 09:18:31 pm
content: Existing techhttps://hydracellpower.com/collections/fuel-cellshttps://www.google.com/search?q=aquacell+battery

author: SiliconWizard
author_rank: Super Contributor
timestamp: August 07, 2019, 09:18:59 pm
content: lyophilized battery?

author: Mr. Scram
author_rank: Super Contributor
timestamp: August 07, 2019, 09:22:51 pm
content: Just freeze dry a regular battery. This isn't new technology.

author: james_s
author_rank: Super Contributor
timestamp: August 08, 2019, 01:15:22 am
content: I got a surplus radiosonde once that had a water activated battery. It was an ideal tech for a disposable item that needed a long shelf life but I wouldn't bother with them for household uses.

author: edy
author_rank: Super Contributor
timestamp: August 14, 2019, 10:36:07 pm
content: What happens if you have a lead acid battery but dry... that is, you do NOT have any acid in it. Just the metal plates in the casing waiting. And you have a "pouch" of dry power ingredients when you mix with water you get just the right concentration of sulphuric acid which you proceed to pour into your battery. Would this work the same?

author: rhodges
author_rank: Frequent Contributor
timestamp: August 14, 2019, 11:49:25 pm
content: Quote from: edy on August 14, 2019, 10:36:07 pmThat is how I bought motorcycle batteries. The sulfuric acid was separate. But I think that I was supposed to charge the battery after adding the acid.

author: edy
author_rank: Super Contributor
timestamp: August 15, 2019, 12:17:52 am
content: Quote from: rhodges on August 14, 2019, 11:49:25 pmSo the battery is not going to have any charge upon initial addition of the sulphuric acid? It looks like there is a product for dry charged batteries where they ship you the battery dry, you add the electrolyte (which you theoretically could perhaps even ship "dry" and add distilled water), and away you go:http://support.rollsbattery.com/support/solutions/articles/437-activating-dry-charged-batterieshttp://support.rollsbattery.com/support/solutions/articles/427-activating-instructions-dry-charged-batteries-detailed-Obviously it is more dangerous and technically challenging than the JAW type batteries, but I see this potentially can also be recharged whereas I am not sure if JAW are disposable or can be charged back again.

author: rhodges
author_rank: Frequent Contributor
timestamp: August 15, 2019, 12:31:16 am
content: QuoteYes, it has a charge. Maybe even a 70% or 80% charge. I have used these batteries immediately after adding the acid.But they still recommend using a battery charger before using it to start the motorcycle.

author: edy
author_rank: Super Contributor
timestamp: August 15, 2019, 01:29:49 am
content: Here's the relevant website on IndieGogo:https://www.indiegogo.com/projects/jaw-batteries-world-s-first-emergency-batteries#/On the face of it, seems pretty neat... They show capacity and discharge curves equal to or above that of Alkaline. So they claim! If we are to believe this is all true, they have working product and they are ready to sell, why put it on IndieGogo? They want exactly $28,746 to fund the campaign but it has a flexible goal which means they will get the money even if it never reaches that.That is too little to really do much. They can't build a factory with that money. What are they trying to fund exactly?A starter pack is $10 (4 AA's). For $19 you get 8 AA's.Now you can purchase 4 AA Lithiums (which have a shelf life of 15 years) for about $5 now:https://www.amazon.ca/Energizer-Ultimate-Lithium-Batteries-Each/dp/B00003IEMEThe cost for these JAW batteries I'm sure will drop, and the idea is cool but something rubs me the wrong way about this campaign and I'm not sure why.I'm looking at that capacity bar graph and at 100 mA current draw it has 800 mAh capacity, and at 300 mA current draw it has 600 mAh capacity. How does this compare to a typical Lithium or Alkaline AA? I know we are not comparing apples to apples here... and the main benefit of these batteries is the long shelf life. But if we are to consider even "reasonable" disasters... they are on the order of months, I think stocking up regularly every 3-5 years and buying a fresh pack of batteries (and using old stock first for non-emergency use) periodically would cover you in case of emergency.I'm looking at test curves done here:https://www.powerstream.com/AA-tests.htmThey are showing a Duracell/Radioshack topping out at around 2 Ah. Compared with the JAW battery at 800 mAh. Am I miscalculating or missing out on something here?Also notice the Lithium batteries (E2) in their first test discharging at a whopping 2 A rate, they are lasting 2.8 Ah! The alkalines are in the 0.5-0.7 Ah range., with Energizer Titanium beating the pack at 1.18 Ah. Our JAW battery at 300 mA discharge is about 0.6 Ah according to their bar chart. Again, how poor is this JAW battery compared to other technologies out there, and do you really need 25+ years shelf life (with a huge cut in capacity and greater costs) over an existing much greater energy-holding battery with 15 years shelf life? What Armageddon scenario is this extra time benefiting?Here is the datasheet on Lithium from Energizer:http://data.energizer.com/pdfs/l91.pdfLooking at the curves in the above PDF file, the Energizer Lithium AA seems to be around 3500 mAh abroad a large range of power current draw, as tested from 1mA through to 1000mA constant current down to 0.8V. And there is a steep drop-off... it stays above 1.2V most of the way to the 3500 mAh capacity and then falls off a cliff at the very end.So we have a HUGE performance difference between JAW and Lithium batteries, and their main selling point is shelf-life for emergencies. Maybe environmental impact? But if you recycle that can be mitigated as well. Why would anyone want to buy a JAW battery then, that offers a quarter of the capacity (at best) at double the cost? And involves fidgeting with adding water and waiting and drying the thing?

author: m98
author_rank: Frequent Contributor
timestamp: August 23, 2019, 03:48:07 pm
content: Have you ever seen any regular customer check the datasheet or specs of a battery? As long as they stay in the "emergency/survival/outdoor" niche, I see that people would buy their product. There much more impractical things than this on the market.Similar water-activated dry batteries do already exist, and they probably have some obscure OEM who already manufactures these for them.

author: mzzj
author_rank: Super Contributor
timestamp: August 23, 2019, 06:14:12 pm
content: Cute.Eneloop NiMh retains ~70% charge after 10 years. Wild guess from available data could indicate >50% still after 20 years, putting it ahead of this dry battery.Or the mentioned Energizer lithium 15 years with with 4 times higher capacity. Probably +25 years before it has fallen to the level of these.If low current is enough Tadiran XOL 40 years.