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Trying to construct a battery powered usb hub. Will this work?? Answered

Let me start of by saying that I suck at electronics and to tell me to build something from scratch would completely miss the point of why I am asking this :P
What I want to do is use readymade components to combine into a portable usb hub.
I want it to be highly customizable and powerful enough to power several usb devices at once. Such as powering several usb speakers, recharging a phone and so on for extended periods of time.
And it has to be as energy efficient as possible without costing a gazillion bucks. If I was not at all worried about wasting power I would have solved it already :P

Here are the parts I have picked out.

1. 12V Rechargeable Li-on Battery 9800mAH


2. Hobbywing UBEC-8A 


3. Powered 7-Port Usb hub


I hope someone can help me out with confirming that my setup would work. Or tell my exactly why it would not. I would greatly appreciate it :)




8 years ago

I am writing an answer based on the following information provided by you.

1. Your power source is a Lithium Ion rechargeable battery at 12V DC
2. Your power source is to be converted from 12VDC to 5VDC
3. The resultant voltage is to be used by the 7-port USB hub.

There is no issue 1-2, but 3 may pose the following:

The USB 7-port hub shown in the website I followed does not detail what DC voltage source it requires. Generally, it SHOULD be 5VDC (from the power plug pack) but this may not always be the case as the internal circuitry may require a higher voltage for it to-step down or to also power other ancillary devices like fans, LEDs, oscillators for the HUB controller, etc.

If it IS a 5VDC input into the hub, you should be right to go; depending on how you want your setup to look like.

Obviously you will need to re-charge your battery, so that will limit how you package the entire unit. Will you have the battery power the USB hub ALL the time? or only use it when you are away from a GPO (general purpose outlet)?

These factors will determine if you will want to fashion a portable power supply or build the battery within the hub itself (by the looks of the size, I don't think that will be really possible).

Furthermore, USB hubs have internal circuitry that switches from 'upstream' power supply to 'on-board' power supply. (i.e., from your computer - upstream or from the DC plug 'on-board').

I think the best way to go about it is to create a 5V portable power supply in isolation; the battery and the voltage converter in a single unit; then find a 5VDC DIN plug (the same as that on the USB hub input) so you can use both battery or AC-plug input to the USB hub. You can then also charge the battery back when you're not using it.

There are a few more considerations I have in mind, but I will leave it at that for you to suggest.

(I am a qualified, professional electrical & electronics engineer, with studies in power electronics, distributed power systems, electric drive systems and traction systems.)


8 years ago

It should work.

You need to check that the input voltage to the hub is 5 volts and DC not AC or another voltage.

You'll have to hack the plugs since they won't be plug and play.


Answer 8 years ago

Thanks alot :)
I just assumed that it was 5v dc in on the hub since other ones I looked at was. But I guess not all hubs are the same. Will check with the seller to make sure.

Will go ahead and order the rest of the stuff then.


Answer 8 years ago

It probably is but there is always the chance that it isn't.


Answer 8 years ago

+1 -- this looks like it should work - just make sure the hub actually supplies power to the ports when just the external power source is connected -- otherwise the hub may need power applied to the usb host port...


Answer 8 years ago

Missed that completely :P Should stop asuming things I guess. Thanks.