The best solution is to build a battery pack using a large 12 or 24 volt Lithium Iron Phosphate (LifePO4) battery. The batteries are not cheap - usually $500-800 - but will last forever and can be used with any CPAP in case you get a new CPAP or change models or whatever.
CPAPs usually have car/vehicle adapters that you can buy. This would connect to the battery to power your CPAP at night. The battery should last many years - perhaps a decade - with normal use and charging. I don't recommend buying battery packs made by the CPAP companies because they are very expensive (like $300) and sometimes don't last through the night or can't be used with heating. They will also wear out and die soon because they are so small they can't handle so many full cycles. And you can only use them with that particular model, so that is another reason to spend a bit more money and buy a GOOD battery that will last forever and be universal.
We can help you pick out the battery and attachments and even put it together for you as part of our consulting if you would like. You can click the link below, and we can get you all setup!
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