From: Bob Blick <bobblick@outlook.com>
To: Microcontroller discussion list - Public. <piclist@mit.edu>
Sender: "piclist-bounces@mit.edu" <piclist-bounces@mit.edu>
Date: Sun, 16 Feb 2020 18:58:58 -0800
Subject: Re: [EE] large USB power banks
Thread-Topic: [EE] large USB power banks
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Fire, electric shock, lawsuits... just the usual. No danger from timeline s=
hifts, black holes, Thor, Shiva, etc.

If you don't open up the power banks, or power them from more than 5.25 vol=
ts, you aren't adding any more risk than they already pose(which varies con=
siderably between manufacturer). But don't forget to add in the liability y=
ou accept with home-wired electronics. House burns down? Forget any insuran=
ce claim, and expect a bill from the police and fire department. Or not.

Friendly regards, Bob

________________________________________
From: piclist-bounces@mit.edu <piclist-bounces@mit.edu> on behalf of John F=
errell=20
Sent: Sunday, February 16, 2020 6:31 PM
To: piclist@mit.edu
Subject: Re: [EE] large USB power banks

I have a repurposed PC power supply on my bench That I have been tempted
to use power/charge multiple devices. What risks might I be taking?


On 2/16/2020 6:48 PM, James Cameron wrote:
> I've also used single cell USB power banks in some quick hacks.
>
> Where I've wanted less than 5V, I've taken power directly from the
> cell terminals on the PCB.
>
> This defeats the discharge protection, so you have to add your own, or
> procedures.
>
> It can also confuse any coulomb counter in the pack.

--
John Ferrell de W8CCW
"We must never become too busy sawing to take time to sharpen the saw."
Source: Ergonomic Trends

-
--=20
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