Say I have a portable power bank with two USB ports providing 2a each. If I connect both the ports to the same device using a Y cable would I therefore have an output of 4a?

  • \$\begingroup\$ You could have an output of 4A, but whether the device you connect to it will draw that much is an entirely different matter. You may also need to be concerned about balanced cells and not draining one faster than the other. \$\endgroup\$ – Ron Beyer Dec 3 '17 at 6:16

As you said if want to charge somthing at 4A(thats a lot of current). If you want to charge mobile at 4A by Y connector then its not possible. You smarphone's battery limit current to 1A/2A to charge it safely. If it charge at 2A max then nothing happend if you use connect Y connecter with both USB ports. It always limit current to 2A.

Also for smartphone only quick chargers can handle that much currentbut it also have inbuilt circuit and kernel to handle that power.

It is advisable to use stock chargers to charge smartphones or other device to charge it quickest.

| improve this answer | |
  • \$\begingroup\$ Thanks, i'm not using this for a mobile phone or anything. I bought an x86 single board computer that recommends 4A and I want to try to make something portable with it so i'm looking for a battery solution. \$\endgroup\$ – airide101 Dec 3 '17 at 6:50
  • \$\begingroup\$ Yes if load need upto 4A then this thing works. \$\endgroup\$ – user3785133 Dec 3 '17 at 6:51
  • \$\begingroup\$ Awesome! Btw, a USB cable wouldn't have a problem carrying a 4A load then would it? \$\endgroup\$ – airide101 Dec 3 '17 at 6:54
  • \$\begingroup\$ That might be a problem if you dont have thick wire. It will result in the voltage drop at load. \$\endgroup\$ – user3785133 Dec 3 '17 at 7:05

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.