I have a crummy laptop with only one USB 3.0 port and not enough power on that port to charge anything any fast. There are a lot of cheap USB 3.0 hubs on the market that support external power.
What I want is to make some additions to laptop's power cable an install some USB charger to provide power for the hub on the go (only one cable from the socket and two cables from the laptop's charger). It seems that the most universal and non-destructive way would be to add some sort of "splitter" between the AC cable and the charger ("mickey mouse"/C5 to "minnie mouse"/C5 plus usb or something in between) or use some customized AC cable because that connector is universal and I can use the same device for any laptop in future.
The question is: are there any ready to use devices on the market or any comprehensive DIY instructions? It seems like a problem many people have yet so far I couldn't find any solutions at all.
The theoretical device can either output USB-like DC to micro-USB (micro-USB 3.0?) or something more special to the hub (some hubs have a round socket for power connection), anything will do.
I saw some universal laptop chargers with extra USB ports but I don't really want to replace my charger with it, I want to go further and have a special power cord/power cord extension that fits any charger.
Extension is probably better than a cable because I travel a lot and use different cords in different countries instead of a flimsy adapter. So right now I have three different cables (might need even more in the future) and I don't wanna have to modify them all — "mickey mouse" (IEC 60320 C5/C6) is more universal than AC plugs and sockets.