[SOLVED] Additional Power For Laptops with Non-Removable Battery

[HoustonAerosFan]

I've noticed most laptops today do not have removable batteries (or for that matter, DVD drives) any more. If I buy one of these things and I'm on a long flight with no A/C power or USB outlets (~90% of my flights), how do I get supplemental power if I need it?

 

[geofelt]

There are devices like this:
https://www.amazon.com/RAVPower-Por...al-Indicator/dp/B00HFMUBYG?ref_=fsclp_pl_dp_1

Today's laptops are very energy efficient.
I would imagine that even a 10 hour flight would be ok.