Dreamstation Go Portable Battery(ies) that can go on planes and last a few days

Hi everyone, first-time poster.

I have a Dreamstation Go unit (travel APAP) that I have been using for the last few weeks, which I really love. However, I am planning to hike the Inca trail over Christmas which poses a few... logistical problems:

(1) I will need a portable battery (or batteries) that will get me through three nights with potentially no ability to charge them during that time.

(2) The batteries will need to pass airport security "A maximum of two (2) individually protected spare lithium ion batteries with a rating of 100 Wh but not exceeding 160 Wh may be carried per passenger in carry-on baggage only*, pending approval by Air Canada airport agents." Not to mention the Peruvian airlines...

(3) They will need to hold up reasonably well at high altitudes.

Some background... Relatively fit guy (normal BMI) in my twenties who was diagnosed with OSA at around age 18. AHI untreated is 75 (!) My Dreamstation Go is giving me AHIs of 2 - 3 every night with pressures ranging from 7 - 8.5, so I consider that a success. The machine does not have a humidifier.

I thought I did my research well, and so I bought a Paxcess 100W power station on ebay. Much to my surprise, it was seized at the border from the US to Canada! Ebay ruled in my favor and gave me a refund, but that isn't exactly a glowing recommendation for carrying one of these things to a foreign country.

I know there are proprietary battery packs for my machine, but they are about 400-500 CAD each, and will probably realistically only last me one night at high altitudes, so I would have to buy three to the tune of 1500! If it comes to that, I will, but I am looking for any reasonable alternatives. You could say I'm crazy for willing to pay that much, but I don't want to risk not being able to breathe on a once-in-a-lifetime vacation. Google high-altitude pulmonary edema! Peru is about 3400m, by the way. I have spoken to my doctor about prophylactic acetazolamide as well...

I'm looking for any guidance you can give me! I realistically have about 5-6 weeks to find a solution, but I would like to put any batteries through its paces before lugging it along a mountain. I really appreciate this forum as it has helped me many times before.

Thanks a lot!!

I have seen the Lithium ion battery packs at Costco that are intended to recharge cell phones. I wonder if there is some way to put them in series to get the necessary voltage to run a CPAP.