Sanity check on spliced charger

[jcun4128]

I want to know if I'm going to burn my house down with what I've made lol.



This is a hardware fix for the PBP not waking from sleep.

My intent is to just have it plugged in most of the time but this will have a python script running on pbp to check battery voltage eg. between 20-80% and then tell the charger to stop charging or to charge.

This whole thing works. I was just concerned with the temperatures... maybe there is an obvious reason you should not do this.

With a bench top power supply it pulls 5V at 2.58A when the battery is in 50% range... maybe it pulls more when battery is near 0%.

I measured 106F bottom of the PBP case and 122F on charger surface. It was 80F in the room (AC broken).

[jcun4128]

Ehh... decisions been made to use a separate power supply sucks two plugs.

I will check the temps after.

They are cooler so far, seems obvious, add more load, works more (wall adapter).

122F/106F (wall adapter/laptop base)

101F/100F

Well... it's slowly starting to rise

wall adapter is now 114F, laptop at 104F

... if they're the same temps as before I'm going to keep the single power source.

[KC9UDX]

You're using the "barrel jack" and USB-C at the same time? If so, that's a big no-no. The PBP cannot handle that.

[jcun4128]

No just the barrel jack, I actually haven't used USB-C to charge yet

edit:

I had to swap GPIO2 with RX since GPIO2 is high on boot and high side relay was being triggered.

I am now using RX pin and setting it to low in setup... this seems to be stable.

Now I just gotta think about the charging logic since it's weird to have it turn off at 80% then 5 minutes later say it's 78% start charging again to get back to 80%.

[wdt]

There are (rare) bluetooth switches, hard to find and a little expensive
Obviously, goes between wall and charger dongle
You would probably have to send turn on and turnoff signal twice (with 2s pause),
because of slightly delayed waking

[KC9UDX]

You simply need hysteresis for the charge level. Say, you turn on at 70% and turn off at 80%. Or turn on at 78% but turn off at 82%.

I'm not really sure what you're gaining anyway. What does charging under software control have to do with the not-waking problem?

[jcun4128]

I don't know how to fix the "won't wake" issue with sleep/suspend/hibernate (not sure which one) for PBP.

So this charger just keeps the PBP on all the time with battery around 80%

The LCD turns off in lid close

Anyway so far it's working great.

I will have a PBP with an uptime of 1 year you'll see (lol)

[wdt]

my uptime (just woke it up) 192 days
So it is possible,, but only if you do VERY specific things (and have NO nvme)

Lithium batteries have a VERY long life if they are not over 80% AND cool

[jcun4128]

What are you running on it? Do you have that old uboot that has working suspend?

Anyway even if the battery keeps it up... if it freezes sometimes I have to restart. Kills the streak, too many Chromium tabs open.

[KC9UDX]

Wouldn't it be simpler to modify the charge controller in the PBP?

Fwiw, all my PBPs spend the vast majority of time on the charger, and none of them exhibit noticeable loss of battery function yet (3 years for the oldest ones).