30 second recharging Rechargeable Battery

[Jay_Diddy_B]

Hi group,

Here is another Kickstarter project with technical challenges:

https://www.kickstarter.com/projects/shawnpwest/30-second-charging-rechargeable-battery

In the FAQ the stated capacity is 1150 mAh.

So we have 1.5V x 1.15A x 60 x 60 (conversion to seconds) = 6210 Joules.

These Lithium Ion super caps:

http://ca.mouser.com/new/Taiyo-Yuden/taiyo-yuden-lithium-ion-capacitors/

in the package that is close to fitting an AA battery (12.5mm diameter x 35 mm) is 40F

Charge these to 3.8V we have:

1/2 CV² = 0.5 x 40 x 3.8² = 288J

If you allow for the fact you can discharge to 1/2 the maximum voltage, you can extract 3/4 of the energy:

288  x 0.75 = 216 Joules

We only have  1/30 of the energy required 

Charging

If the rechargeable battery had a useable capacity of 6000 Joules, we would need 8000 Joules.

8000J / 0.5 x 3.8 x 3.8 = 1100F


We would need 1100 Farads.

I = C dv/dt

= 1100F x 2V /30s = 73 Amps 


I detect a few problems 

Regards,

Jay_Diddy_B

[EEVblog]

I detect a few problems 

No kidding!

 

[ludzinc]

You win again, immutable laws of Physics!

But wait - it's lasted for *days already in his daughters toy*   

[george graves]

Well, regarding the whole charging time thing....I can't think of a reason why a second set of rechargeable batteries wouldn't solve the problem.

[Fsck]

http://hackaday.com/2014/07/17/a-lithium-ion-supercapacitor-battery/

Apparently hackaday does not compute either.

[EEVblog]

http://hackaday.com/2014/07/17/a-lithium-ion-supercapacitor-battery/
Apparently hackaday does not compute either.

According to the inventor:

The capacitor is 270F and the esr is 40 milliohms.

So where is this magic 270F cap coming from if the best that seems to fit is 40F?

[Bracken]

Aside from the already mentioned technical problems, he's clearly gone to kickstarter a tiny bit early in this project.

I decided to give it a shot anyway, for £15 I can live with not actually getting one to rip into, which is what I expect TBH. But also because me backing a crowdfunding campaign is the kiss of death. 

[george graves]

One other thing... He's asking for $10k.  Ok, that covers the BOM....except the empty AA battery shells.  That's going to cost 10k just for the metal stamping dies?  No?

I googled a bit, and there are AAA to AA adapters you can buy, so maybe he's planning on using that.

[tszaboo]

One other thing... He's asking for $10k.  Ok, that covers the BOM....except the empty AA battery shells.  That's going to cost 10k just for the metal stamping dies?  No?

I googled a bit, and there are AAA to AA adapters you can buy, so maybe he's planning on using that.

He is asking for 25 dollars for a battery which is below the capacitor itself.

[con-f-use]

I decided to give it a shot anyway.

Since you are a backer: Could you post  Jay_Diddy_B's little calculation as a comment and ask the creator, what he has to say?
Maybe he got his hands on the next generation of uber-caps 

Might at least stop people from wasting their money.

[Jay_Diddy_B]

Since you are a backer: Could you post  Jay_Diddy_B's little calculation as a comment and ask the creator, what he has to say? Maybe he got his hand on the next generation of uber-caps 

Might at least stop people from wasting their money.

 

I was thinking of pledging $1 so I could do the same thing. It would save me a dollar if you posted my calculation and asked for comment.

Jay_Diddy_B

[con-f-use]

It's a weird notion to pay them so you can criticize their work.

Why can only backers of a project leave a comment? If I were Kickstarter I'd give the option to filter out people who didn't back the specific project, never backed a projected or pledged less than $10 dollars. But that should be optional!

[BravoV]

It's a weird notion to pay them so you can criticize their work.

Its a new business model. 

[mzzj]

The plot thickens: http://hackaday.com/2014/07/26/ask-hackaday-graphene-capacitors-on-kickstarter/

Using home-made graphene and biggest obstacle is  "My biggest challenge is maintaining and steady hand and limiting the coffee intake while soldering these tiny components to assure each and every battery functions as promised"
 

[miguelvp]

That's actually a very interesting development.

I really have no use for a single AA 1.5 v battery other than for testing it and check the super cap on the scope.

I might back it up because now I'm curious.

His mechanical extraction of graphene, not sure what to make of it. I wonder what Robert Murray-Smith thinks about that type of production of graphene. I might ask him.

https://www.youtube.com/user/RobertMurraySmith/videos

[EEVblog]

The plot thickens: http://hackaday.com/2014/07/26/ask-hackaday-graphene-capacitors-on-kickstarter/

From here:
https://www.kickstarter.com/projects/shawnpwest/30-second-charging-rechargeable-battery/posts/926386

If, for some reason you don't believe these claims, well, I invite you to pledge enough to get a battery and run it through your own rigorous tests. I've had 2 in one of my daughters toys for weeks now without recharging and it's still going strong.

Wow, the guy got called out on his bullshit claims for capacity, and now pulls graphene out of his arse!
It was very clear from the original campaign that he was using a lithium ion capacitor, and even showed a photo of it. He wanted the money to mass produce the boards, and now he's saying he needs $8K to have a capacitor manufacture use his own home produced graphene. Wow, I can smell the bullshit all the way over here.

[Jay_Diddy_B]

Hi,
If you read the rewards, there is no mention that you get one of the new batteries, it is only implied because of the context:



He could send you any cheaper battery and charger. What do you think?

You call that a bullshitometer  This is a bullshitometer:




Jay_Diddy_B

[rsjsouza]

In the FAQ the stated capacity is 1150mAh

I did not watch the video or anything, but from the FAQ alone you can't assume this is for the AA size. Obviously that for any other size this would be a lousy capacity.

[qno]

As soon as you need/use anecdotal evidence, alarm bells start to ring.

With some simple math you can calculate this is not gong to work.

[miguelvp]

So I got a response from Robert Murray-Smith  as he has explored numerous methods of extracting graphene so he is the most expert person in my reach for the subject.

And his answer is that the one day process in the ball mill is a waste of time, the wet milling could be doing something but what he is skimming off the top wont be graphene as it will stay in solution.

Also he noted that the pictures do show the capacitor. So he doesn't buy it either that it was originally a graphene super cap.

[Rasz]

Robert Murray-Smith  as he has explored numerous methods of extracting

about Robert Murray-Smith :
"I'm primarily interested in free energy "

Asking one free energy nut about another free energy nut. This is priceless

[miguelvp]

He is a very knowledgeable chemist, that's where his expertise is at so I did ask him about the production of graphene not the actual feasibility of the device. Just because he seeks free energy it doesn't take away the validity of his knowledge in chemistry.

Also, there if many concepts of free. One is free as in free beer, but not as in getting beer out of thin air. Solar energy is free as in available for everyone to use.

[echen1024]

Huh. Exactly what is a "Lithium Ion Capacitor?" 

[miguelvp]

Huh. Exactly what is a "Lithium Ion Capacitor?" 

Here is a pdf with Taiyo Yuden presentation of their LIC

http://www.mouser.com/pdfdocs/LICpresentationforstorage20131110.PDF

[EEVblog]

My take on this:
http://www.eevblog.com/2014/07/28/graphene-lithium-ion-capacitor-kickstarter-bs/