Portable battery bank to charge a laptop?

Let me start off by saying that this problem may well have no possible solution and I'm probably a fool for asking.
I was wondering if there's any simple(ish) way to use an external battery bank with 2 USB ports on it to charge a laptop? The bank has 18,000mAh of capacity, one 2.1A, 5V USB port and one 1A, 5V USB port (total 15.5W). The laptop charger in question runs at 19.5V, 2A DC (total of 39W) and the laptop battery has a 3800mAh rating.

Thanks in advance for any replies :)

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Girinata2 years ago

Same, I have same idea but with different source,not from usb port but from other charger. it's like MPPT device for solar cell. but I still confuse how to make it..

Girinata2 years ago

Same, I have same idea but with different source,not from usb port but from other charger. it's like MPPT device for solar cell. but I still confuse how to make it..

Girinata2 years ago

Same, I have same idea but with different source,not from usb port but from other charger. it's like MPPT device for solar cell. but I still confuse how to make it..

Girinata2 years ago

Same, I have same idea but with different source,not from usb port but from other charger. it's like MPPT device for solar cell. but I still confuse how to make it..

Girinata2 years ago

Same, I have same idea but with different source,not from usb port but from other charger. it's like MPPT device for solar cell. but I still confuse how to make it..

If you want to charge the laptop from a battery bank then you'll need connect it to the power connector on the laptop. So the battery will need to provide the 19.5V and support the 2A load. Or you can use a 12V battery and a 100W inverter to use the laptops power brick to charge the laptop.

CustardInc (author)  mpilchfamily3 years ago

Thanks for the suggestion, I only thought of it because I have a pretty high capacity power bank that's fairly small, at least compared to a battery +

Um what kind of laptop do you have that the battery is sealed inside i have never seen a laptop with a PERMA battery?

Like all Apple laptops. More and more devices and laptops do not have a means of accessing the battery without completely pulling apart the housing. The idea being, by the time the battery wears out they rather have you buy a new laptop then try and replace the battery. More and more companies and building in planned obsolescence to keep people coming back to buy more.

iceng3 years ago

Easy enough to feed a 5v to 20v with an inverter running on the 2.1A USB port.

That is a 4x voltage gain and 4x current drop about 1/2A output.

Recharge that 3.8Ah battery in one 8hour day.

verence3 years ago

No. For reasons Vyger explained. Or you would have to build (buy?) a voltage converter from 5V to 19.5V.

Why not just bring another laptop battery?

CustardInc (author)  verence3 years ago

Like more and devices these days the battery is sealed inside

Vyger3 years ago

Not by USB.

USB power goes one way, from the source (a computer or a battery or a wall charger) to the USB device. The laptop is not a USB device. It would be like plugging 2 cords from different outlets together. Power does not go from one outlet to the other outlet. You can use an external battery to power a laptop but it needs to have the correct adapters. You would need to do a lot of modifying.

CustardInc (author)  Vyger3 years ago

hmm, I thought it was worth a shot. Thanks for ruining it for me ;)