What off the shelf portable power source for air sense 10?

Awhile ago I was trying to configure some Milwaukee batteries to run my cpap.
While I still want to make that work, I’m looking for an off the shelf solution 3-5 nights would be ideal.

Jake00 wrote: ↑

Sat Aug 07, 2021 6:34 am

3-5 nights would be ideal.

You're going to need a big mobility scooter battery, a ResMed converter and a charger for the battery. No humidifier usage.

Study the ResMed guide on batteries - https://document.resmed.com/en-us/docum ... lo_eng.pdf

Thinking about something like this https://www.amazon.com/ROCKPALS-Portabl ... merReviews

Jake00 wrote: ↑

Sat Aug 07, 2021 6:34 am

Awhile ago I was trying to configure some Milwaukee batteries to run my cpap.
While I still want to make that work, I’m looking for an off the shelf solution 3-5 nights would be ideal.

I would get a 50Ah LiFePO4 Battery Deep cycle lithium iron battery and a 12volt DC-DC converter for your CPAP machine. Those tool battery is too small capacity for 30-50Ah use for 3-5 nights with humidifier on level 4 and a correct DC-DC converter is needed.

Jake00 wrote: ↑

Sat Aug 07, 2021 8:34 am

Thinking about something like this https://www.amazon.com/ROCKPALS-Portabl ... merReviews

The specs say it is 500 watt hours. 500 watt hours at 24 volts = 21 amp hours (https://learnmetrics.com/watt-hours-to-amp-hours/)

Check the ResMed guide in the link, and you will see 21 AH won't do what you want it to do.

Tony415 wrote: ↑

Sat Aug 07, 2021 1:21 pm

I would get a 50Ah LiFePO4 Battery Deep cycle lithium iron battery

That battery will cost him close to $450.

He can get a 55AH SLA AGM battery for around $170. Much better choice.

He should still calculate his AH needs from the ResMed guide.

Jake00 wrote: ↑

Sat Aug 07, 2021 8:34 am

Thinking about something like this https://www.amazon.com/ROCKPALS-Portabl ... merReviews

That will give you just a *little* more than a 35AH lead acid battery, (which costs about $70 dollars, and will still require the Resmed DC adapter.

So, sure, if you've got a lot of money to throw away, go for it.

ChicagoGranny wrote: ↑

Sat Aug 07, 2021 4:14 pm

Jake00 wrote: ↑

Sat Aug 07, 2021 8:34 am

Thinking about something like this https://www.amazon.com/ROCKPALS-Portabl ... merReviews

The specs say it is 500 watt hours. 500 watt hours at 24 volts = 21 amp hours (https://learnmetrics.com/watt-hours-to-amp-hours/)

Check the ResMed guide in the link, and you will see 21 AH won't do what you want it to do.

Well, watthours are watthours. a 35ah lead acid scooter battery is about 420wh (for $70) and that'll last several days.

What you need to do is convert whatever the battery says in AH into WH, getting past the misleading marketing wank that lithium battery packs have, like "50,000mah" of course, the 'm' means 1/1000th, so 50,000mah is 50ah, but that's usually at 3.6volts, so that really impressive 50,000mah works out to a measly 180wh, which *might* get you through two nights. (80-90wh per night).

ChicagoGranny wrote: ↑

Sat Aug 07, 2021 4:14 pm

Jake00 wrote: ↑

Sat Aug 07, 2021 8:34 am

Thinking about something like this https://www.amazon.com/ROCKPALS-Portabl ... merReviews

The specs say it is 500 watt hours. 500 watt hours at 24 volts = 21 amp hours (https://learnmetrics.com/watt-hours-to-amp-hours/)

Check the ResMed guide in the link, and you will see 21 AH won't do what you want it to do.

Although the ResMed is a 24V device, that's after the conversion from 12V.

Since the the actual draw from the battery is 12v, would the Amp Hour conversion be 42 AH?

Dog Slobber wrote: ↑

Sat Aug 07, 2021 5:08 pm

Since the the actual draw from the battery is 12v, would the Amp Hour conversion be 42 AH?

Yes, according to this converter - https://learnmetrics.com/watt-hours-to-amp-hours/

Thank you for the correction.

palerider wrote: ↑

Sat Aug 07, 2021 5:06 pm

What you need to do

Agree now?

What's with all the math? When I signed up here - there was a promise (I think) of No Math!

JLROhio wrote: ↑

Sat Aug 07, 2021 6:18 pm

What's with all the math? When I signed up here - there was a promise (I think) of No Math!

*grabs eraser* show me where you saw that.

Not only is that thing overpriced they mention the battery is not replaceable. The video in the link shows him using AC and using the humidifier - I would prefer to use the correct DC cable for the cpap. It also mentions the recharge cable that comes with it is an AC charger while it has other options to charge those are extra money.

I would prefer any jump starter to that thing. But have use this one for some time now
https://www.cpaptalk.com/viewtopic.php? ... 50#p434501

Yeah, limited budget is difficult.
I would go with a car battery. Or even just use it from the battery in the vehicle he drives to the camp. Just start the vehicle every day to charge the battery. He does not need to buy extra battery just for going camping once awhile.

You might opt for a car battery, but you would be choosing the poorest option. Jim