Can i use a external cell phone battery to partially charge a laptop via usb? (PIC)

[JEDI]

6000 mah

what if i got a usb to laptop power plug cable?

 

[TheStu]

I... what?

The first problem is that your average laptop DC input is something like 19V, and USB outputs 5V.

 

[firewolfsm]

USB wouldn't provide the necessary voltage or power to do anything effective. If you're going to buy something to charge the laptop anyways there are better options, solar panels even.

 

[marcplante]

There are larger power bricks that can supply power to a PC. they're not going to be as portable. The smaller units can charge phones, the larger portable units can charge tablets.

 

[Wintek]

No. Laptop batteries fully charged are ~11 or ~14V. Power supplies feeding the laptop are 19V. For the 5V USB based charger to charge the higher voltage laptop battery, there would need to be step up voltage circuitry in the laptop USB circutry, which there is not. I suppose you could kludge something together like putting three of the external cell phone battery chargers together in series and attach it to the power connector on the laptop, but I would not recommend that.