From: RussellMc <apptechnz@gmail.com>
To: Microcontroller discussion list - Public. <piclist@mit.edu>
CC: Rod Macdonald <essel@slingshot.co.nz>, ApptechNZ <apptechnz@gmail.com>,
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Date: Thu, 31 Dec 2020 20:16:50 -0800
Subject: Re: [EE] Calculation of the state of safety (SOS) for lithium ion
	batteries
Thread-Topic: [EE] Calculation of the state of safety (SOS) for lithium ion
	batteries
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Note my comments some while ago on this list re a laptop battery fire I
caused by attempting to charge an "abusively stored" LiIon battery.
Copied at end.

PDF related to James' post
    Calculation of the state of safety (SOS) for lithium ion batteries
https://reader.elsevier.com/reader/sd/pii/S0378775316306140?token=3D38E8569=
2F3B6D0DA7CB1CAB59CB417F73D90C914E78F8B8E10ADA9CC96F589D5E1FBD6AF1C4B5861CD=
DCA9838D6F7A17

Also free
    A Study of Cell-to-Cell Interactions and Degradation in Parallel
Strings:Implications for the Battery Management System
https://reader.elsevier.com/reader/sd/pii/S0378775316309995?token=3DF4B770C=
C19E7803FAC37AFC04594112A550591C7066844ECDEB83871DD5824DE3FF54E1B6FCC413A40=
EFCCC396C4D03D

______________________________________

Copied from my November 14 2020 post:

I found an old small laptop/notebook in a dumpster.
After cleaning up it powered up OK when the power supply was connected but
had no or minimal battery life.
It did not seem to take charge.

I (very stupidly) left it plugged into the power supply, battery in, and
sitting on some papers on a couch in our lounge.
It remained that way for some days - maybe 1 to 2 weeks.

One evening I was attracted by loud yells, stage lounge off.
I entered to find a classic example of 'vent with flame' in progress.
Laptop and I exited stage left rapidly and I removed the battery in the
yard and left it to burn.

Somewhat surprisingly the laptop survived the conflagration, somewhat
warped but still operational, as the battery was clipped on at the rear and
relatively unshrouded by the case proper.
The papers on the couch were nicely charred. A paper exercise book
immediately below the flame point acted as a complete downward firebreak
for the brief period concerned.
The cloth surface couch was blackened by the copious black smoke but
cleaned up with only some residual scuffing to show for its ordeal.
Had this happened when we were not in the room the loss of the house would
have been a ppssibility.
Some lessons were learned.

   Russell



On Thu, 31 Dec 2020 at 20:30, James Cameron <quozl@laptop.org> wrote:

> https://www.sciencedirect.com/science/article/pii/S0378775316306140
>
> A paper from 2016 that may be of interest.  I referenced it today in
> trying to figure out risks of storing children's laptops for a few
> years before using them.
>
> I also carefully charged an abusively stored battery, with temperature
> monitoring and an office escape plan.  The battery was from a batch
> manufactured five years ago.  No issues.
>
>
--=20
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