Can I charge a laptop with two power banks?

No, you cannot charge a laptop with two power banks. Not without an adapter. But then it will take a very loooooong time. That's because of the voltage and amp. You get upto 5v and 2A as standard power bank specs. Solar Power Bank Quality Assurance: Power Bank phone Chargers

Charge laptop with power bank

But standard laptop requirement is about circa 14 to 20 volts 4.62 amps or 65 to 90 watts or thereabouts. It all depends on the type/size of the laptop. The batteries are larger and heavier. You can’t really get that kind of capacity from a mobile power bank.

However, there are desktop portable laptop chargers that you can buy. They are power banks as well but not the small size you might have in mind. They have the big spec/capacity you need to quickly charge up a laptop.

You are probably better off with a laptop solar charger if you live in region with generous sunshine. Just spread out your solar charger and plug in your laptop or phone. The benefit of this is that its not heavy. You can also get a spare battery for for your laptop. You charge up in the day and you have a backup for use at night. 

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