Something just occurred to me…how are you going to limit each USB port to 60W and/or limit the total to 120W? The pack will try to draw as much current as it can.
The pack can try to draw as much as it wants, the power adapter will not provide more than its rating
That’s my concern…standard CV power supplies like the adapters will shut down to prevent damage if you try to run them at above their ratings. Only constant-current (CC/CV) supplies will limit the current and continue to run.
Also, each port can only handle 100W so you’ll need a way to force them to share current if you are drawing the 120W max of the adapter. You wouldn’t be able to let one port handle the full 120W.
I realllly want this to work but I’m wondering how now that I’m giving it more thought.
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The boost converter he’s using looks like it has two pots, most likely for setting current and voltage limits.
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Ahhh….good eye! That solves a lot of problems. Now we just need the adapter channels to not fry each other or one to just shut down. 
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I think it might have been asked about already but what about two 20V PD outputs going to two BMS/packs in series? Then just use BMS that are ok with series config and that might work good.
or with the series connection still frying the supply?
oh yeah… then you can not use a single port/charger of the two maybe possible… unless you have another port/booster or use for single 20V PD supply or also each port at a time to fully charge, halftime switches no fun though.
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Yup, there would be fire.
The “ground” for the top pack’s circuitry would be connected to the ground for the bottom’s pack circuitry, short-circuiting the bottom pack through those grounds.
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diagramsz plz
I can make a template
You still have the ground issue and fire.
You would need fully isolated power supplies…not cheap.
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That is a valid point, I guess we shall see
This is also true, this boost converter has CC CV but it would be after the PD negotiator board, so it will be interesting to see how this all works out. Maybe I’ll try to put some multimeters between things to get some readings when I set it in motion
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No need, thanks. I have MoochCAD installed… 
Ignore the lack of PD triggers and boost supply. This is just to show how the pack can be shorted. Using two USB adapters, two PD triggers, and two boost supplies would still result in chaos as the boost converters share grounds too.
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Fantastic idea but typically low power and really inefficient. A 100W setup, even 200W, is possible but big and it would get hot. I forgot who but one of the major chip manufacturers has a 200W reference design on their web site.
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no no no It would be like 10 iphone wireless pods covering to bottom of a board like a feeding pig
still only 75W damn
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LOL…that can work but still at least the same amount of total heat and we might be losing a bit of convenience. 
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Umm…7.5W. 
You can get Qi chargers at up to 15W now IIRC.
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so that would make this pic 120W nice.
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Docking station charging would be interesting, where it charges through contact pads or something
could be built into a wall hanger or something
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Someone here mentioned charging through the trucks IIRC, one positive truck and one negative truck. 
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