
A phone that charges in seconds? Scientists bring it closer to reality - dnetesn
http://phys.org/news/2016-11-seconds-scientists-closer-reality.html
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gus_massa
The size of the battery varies from phone to phone, but let's choose 3000mAh
as a typical value so the battery is enough for a full day.

If you want to charge it in "seconds", let's use 60 seconds as an upper bound.

So if the charger has a 100% efficiency, then it has to provide 3000mAh/60sec
= 3000mAh _3600 sec /h /60sec = 180000mA = 18A.

An USB can provide between .1A and .9A. For comparison, a typical plug in a
home can provide 10A. So to charge the phone you will need some big connector,
not a tiny microUSB like connector.

But it's worse. From the article:

> "If they were to replace the batteries with these supercapacitors, you could
> charge your mobile phone in a few seconds and you wouldn't need to charge it
> again for over a week," said Nitin Choudhary, a postdoctoral associate who
> conducted much of the research published recently in the academic journal
> ACS Nano._

To recharge the phone once a week, I guess you will need a 20000mAH battery,
and a few seconds is something like 5, so the connector must survive to 1000A,
that is a ridiculous current.

