[SML] battery packs for practicals

[Jerry Durand]

I've seen an AMAZING number of bad battery chargers.  I used an off the
shelf (COTS) self contained charge controller chip for a customer and in
the prototypes the lithium batteries started getting bloated.  No fires,
but that should NOT happen with chips that are sold as complete charging
solutions.  Especially since these batteries had the protection boards
built-in.

On the next project for a customer that needed two 18650 batteries, I
decided to not trust the commercial chips and wrote my own charge
control routine in the processor with several safety checks and only
charged to "mostly full" instead of trying for the most possible.  Happy
to say the customer has had these running for over a year with daily
charge cycles and hasn't reported any problems.

So, it still seems true that if you want it done right, do it yourself.

On 9/30/20 9:46 AM, Dan Sheehan via Stagecraft wrote:
>
>
> On Wed, Sep 30, 2020 at 12:13 PM Dan Sheehan <dsheehan.sml at gmail.com
> <mailto:dsheehan.sml at gmail.com>> wrote:
>
>     This from local news, via Facebook
>     (maybe somebody could factcheck and share results ?)
>     OR...
>     google "dewalt battery fire" !!!
>     "
>     We heard back from the fire investigators
>     and it was determined that the Dewalt battery/charger
>      was the cause of the fire that burned down our garage and shop.
>     We heard from firefighters & so many other people
>     that this is not uncommon & it's not just Dewalt.
>      All brands have the same issue, so this is our PSA:
>     DON'T LEAVE YOUR CORDLESS DRILL BATTERY ON THE CHARGER AFTER IT'S
>     CHARGED.
>      It was a new battery (within last 6 months)
>      and the flex volt charger.
>      We only had it on the charger for 5 hours. "
>
>
>
>     ...Dan Sheehan
>     Fixer of things that break
>     TD Walpole (MA) Footlighters
>
>     We shall have to evolve problem-solvers galore —
>     since each problem they solve creates ten problems more.
>
>
>
> -- 
> ...Dan Sheehan
> Fixer of things that break
> TD Walpole (MA) Footlighters

-- 
Jerry Durand, WhatsApp, Telegram, VK, signal
www.DurandInterstellar.com & www.Durandinterstellar.ru

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