From: RussellMc <apptechnz@gmail.com>
To: Microcontroller discussion list - Public. <piclist@mit.edu>
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Date: Sun, 16 Feb 2020 15:05:59 -0800
Subject: Re: [EE] large USB power banks
Thread-Topic: [EE] large USB power banks
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On Sat, 15 Feb 2020 at 07:45, Dwayne Reid <dwayner@planet.eon.net> wrote:


> I had wanted to purchase 30 of these power banks - I was going to
> pull the cells from them and build a decent battery box for my
> electric scooter.  Basically, 14 sets of two in series-parallel (14S
> 6P).  Unfortunately, was not able to get that many.
>
That sounds like a good price for good quality 21700 (or similar) size
cells.

Note that even good quality cells may not have high discharge current
capability.
Some 21700 cells are rated at 35 - 45 A max discharge rate (eg Molicell
INR21700-P42) wheres others may have a max rated discharge of under or even
well under 10A. The tradeoff is (usually) that high discharge rate cells
have lower Ah capacity.

In your case the 10.05Ah/3 =3D 3.350 Ah / cell capacity is significantly
below that of the Molicell high discharge capacity cell SO you can *hope *t=
hat
it also is high discharge capacity rated.



                   Russell
--=20
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