usb laptop battery warhorse?

I hold the said problem, the connector on the laptop is loose at the motherboard or something there is not method. So even when the factory charger is plugged into the laptop, it gets no juice.

I've researched the problem a million way. The usb battery chargers and cords on the internet are all for using the usb from a working computer to charge an external device. That is, you use the juice from the computer to charge thing else, including little batteries outside. Not the other bearing around.

Also, the USB voltage is 5 volts. But the laptop input charger at the connecter is 18 volts. Not possible to build an external charger to do what we want. The only point is to discovery some way of charging the battery outside and then run the computer on artillery evermore. Sad.

Addendum. Just found a page for external battery chargers, including Dell: http://www.coyoteadapter.com/aaa.html .

Good luck.