Battery Backup Humidifier use Dream Station 2 cpap advanced

[Meangreen13]

Has anyone successfully ran battery backup for Dream Station 2 CPAP advanced with humidifier and if so what setup were they using. I have a deep cycle 12v with direct 12v adapter however the Humidifier shuts down after an hour or so. Would I be better off with a Lithium Battery setup?

[srlevine1]

The performance of any electrical device is based on its energy usage and has nothing to do with the energy density or type of battery being used. Some batteries store more energy per pound, have better discharge/charge rates, and last longer, but a 35-ah lithium-ion battery delivers much the same amount of energy as a 35-ah deep-cycle marine battery. The key to solving your problem lies in matching your device to the appropriate capacity device.

I would start with the manufacturer to determine the power usage of your device (if you do not wish to measure it directly with a suitable meter). Now determine how long you wish to run the device. And then select a battery solution that provides 150 - 200% of the energy required. DC solutions are always preferred as they are more efficient.

What is your pressure range?

How long do you want to sleep?

Must the solution be FAA approved?

Will you travel or will the use be mostly stationary?

Do you have a budget?

Will you be using it to automatically switch to battery if you lose your primary power?

Will this be used in a normally hot climate?

What is the humidity setting you use? Heated tube? ARE YOU SURE YOU NEED THE HUMIDIFIER?

I have a friend who uses an ultra-expensive, heavy 12V 400Ah Deep Cycle LiFePO4 (Lithium Iron Phosphate) Battery Pack and got one 8h night at 3/1 humidifier/tube setting that used 68% of a full charge. He did it only once and decided it wasn't worth using the humidifier.

What is the rating of your current battery?

[blizardj]

My DS2 would not run on my lithium battery setup in my RV.  The voltage is to high.... 14.2 volts or so.

I ended up running a small, 400 watt (I think), inverter.  Then running the regular 115 VAC, from the inverter.

As a side note.  My old Dream Station 1, worked fine on the DC from the lithium batteries.

Hope this helps.

John

[blizardj]

Wow, to deplete a 400 Ah lithium battery to 68% in 8 hours,  means he was drawing 34 Amps for those 8 hours to use 272 Ah.

That's a lot of power for a CPAP setup.  Mine draws about 3-5 Amps.  Which is 3 to 5 Amp hours for 8 hours, for a total of 24 to 40 Amp Hours.  Which is less than 14% of my 300 Ah capacity. And that is with humidifier and tube heater on.

John

P.S. after rereading the post. I suspect he meant 40 Ah, not 400 Ah. Then the numbers pretty much line up.

[srlevine1]

Wow, to deplete a 400 Ah lithium battery to 68% in 8 hours,  means he was drawing 34 Amps for those 8 hours to use 272 Ah.

That's a lot of power for a CPAP setup.  Mine draws about 3-5 Amps.  Which is 3 to 5 Amp hours for 8 hours, for a total of 24 to 40 Amp Hours.  Which is less than 14% of my 300 Ah capacity.  And that is with humidifier and tube heater on.

John

P.S.  after rereading the post.  I suspect he meant 40 Ah, not 400 Ah.  Then the numbers pretty much line up.

John -- nice catch of the typo. It was 40, not 400.