High power consumption on battery, Resmed Airsense 10

[Zackio]

I have been running my Airsense autoset 10 on a lithium 78AH battery. I am using the official DC to DC adapter.

According to the Resmed battery guide amd everything I have read on the forums, this should do me for a lot of nights.

I have followed the advice:

1. Turn off humidifier,
2. Don't use heated hose
3. Turn onto aeroplane mode

I only get at the very most 3 night's sleep. It must be taking 26amps per night.

According to Resmed battery guide at pressure of ten, for 8 hours, with a contingency of 50% I should need a battery size of 12ah. Meaning a real usage of 6ah.

The threads I have read seem to line up with that and I should be able to go 13 nights. Yet I only get 3.

I can't understand why it's so wildly different.

Does anyone know if there are any other settings to change to help efficiency and can anyone confirm what the real amp hours theirs takes?

[Zackio]

Through my much research I finally found an answer in this thread. viewtopic/t157402/Yet-another-battery-p ... Remed+35ah

It's down to the sneaking marketing of my battery. It's 78ah at 3.7v so at 12v it is only 24amp hour.

[zonker]

your honor, i object!

asked and answered.

[Biomed_ZZZ]

I think Resmed says to get a marine deep cycle battery. Traveling with such a beast with something other than a car would not work (maybe wouldn't work with a car either) but if it was stationary in the event of a power outage it should work pretty well.

[Dog Slobber]

I think Resmed says to get a marine deep cycle battery. Traveling with such a beast with something other than a car would not work (maybe wouldn't work with a car either) but if it was stationary in the event of a power outage it should work pretty well.

ResMed recommends deep-cycle batteries (batteries that can regularly experience deep discharges), but not necessarily marine batteries.

Linked is ResMed's Battery Guide:
https://www.resmed.com/us/dam/documents ... lo_eng.pdf

What type of battery should I get?

We recommend using a deep-cycle battery to power your device outside of an operating vehicle. Determine the battery size (rated in amp-hours or AH) necessary for your specific device using the charts in the “Batteries” section of this guide.

Marine batteries should be avoided, they are not necessarily deep-cycle. They are often more expensive than non-marine because they have have higher build quality to sustain the pounding received in boats, not required for CPAP use.

[Biomed_ZZZ]

I think Resmed says to get a marine deep cycle battery. Traveling with such a beast with something other than a car would not work (maybe wouldn't work with a car either) but if it was stationary in the event of a power outage it should work pretty well.

ResMed recommends deep-cycle batteries (batteries that can regularly experience deep discharges), but not necessarily marine batteries.

Linked is ResMed's Battery Guide:
https://www.resmed.com/us/dam/documents ... lo_eng.pdf

What type of battery should I get?

We recommend using a deep-cycle battery to power your device outside of an operating vehicle. Determine the battery size (rated in amp-hours or AH) necessary for your specific device using the charts in the “Batteries” section of this guide.

Marine batteries should be avoided, they are not necessarily deep-cycle. They are often more expensive than non-marine because they have have higher build quality to sustain the pounding received in boats, not required for CPAP use.

Interesting as I always thought that deep cycle batteries came only in marine form; never realized deep cycle came in any other form. I learned something today! As far as expense, Walmart seems to be about the same for both types and surprisingly a battery store has a better price on a 75 AH RV/marine battery.

[palerider]

I think Resmed says to get a marine deep cycle battery. Traveling with such a beast with something other than a car would not work (maybe wouldn't work with a car either) but if it was stationary in the event of a power outage it should work pretty well.

NOT MARINE.

Many people say "marine deep cycle" like it's a single thing. but it's not. there are *marine* batteries, which are heavier, sturdier and more impact resistant, to take the added abuse on a boat. pounding through the waves...

Then there are 'deep cycle' batteries that are built to withstand more juice being pulled out of them without breaking down... and starter batteries (like in your car) that are built to delivery really high current but only a small fraction of the battery capacity.

So, what you want is a NON-marine, deep cycle battery.

The current generic best battery to get is a "Mobility Scooter Deep Cycle" battery (all mobility scooter batteries are deep cycle). they're fairly in expensive, and they're ubiquitous.... easily found.

[palerider]

Interesting as I always thought that deep cycle batteries came only in marine form; never realized deep cycle came in any other form. I learned something today! As far as expense, Walmart seems to be about the same for both types and surprisingly a battery store has a better price on a 75 AH RV/marine battery.

Newp, you can get marine starting batteries, marine combination batteries, and marine deep cycle batteries... all of which come at a considerable premium, price wise, (for good ones, ie, not the low quality stuff you get at WalMart).

[Zackio]

The lithium does work. It's a jackery type thing, from "allpowers". But it's a very expensive option.

There are situations for it though like portability for charging. I can take it to a cafe, someone's house, or my house to charge.

Mobility battery seems best bet for cost.

[palerider]

Through my much research I finally found an answer in this thread. viewtopic/t157402/Yet-another-battery-p ... Remed+35ah

It's down to the sneaking marketing of my battery. It's 78ah at 3.7v so at 12v it is only 24amp hour.

Yes, marketing of lithium powerpacks is deceptive, using thousands of mAh instead of Ah... And quoting it at 3.7v instead of 12v... Now, if they quoted Watthours... That would be legit.

[Biomed_ZZZ]

So I learned that a deep cycle battery would not necessarily be marine deep cycle but if you can get a marine deep cycle battery for the same price of a standard deep cycle battery - still not marine? I read something about marine deep cycles are not as robust but I'm not so sure about a battery being constructed with the same battery technology and/or components not being the same; I would actually call it BS. I don't see the logic in saying no marine deep cycle if the pricing is the same. Yes, I wouldn't pay $50 more for one unless I was going to be on a boat. I think all sealed batteries don't off gas, at least that's what I've read. All batteries can explode or go on fire depending on certain variables. I don't work in either the car or boat industries but we use sealed lead acid batteries along with other types in the medical industry all the time; I have never come across a deep cycle battery on anything I work on so I don't have a feeling for them. I can tell you that some batteries can take a beating and continue to work pretty well.

I mentioned Walmart for 2 reasons - 1) there's a Walmart everywhere and is readily accessible vs a Batteries Plus or whomever and the car batteries (3 or 4) I have purchased from them have all given me reliable service throughout the years, these were for different cars not for 1 car. I have had less luck with Sears Diehard batteries going back many years ago and figured Walmart would be about the same but cheaper but they have all lasted for quite a while. And yes I know we are talking a different type of battery. Would I buy a battery from Walmart if another battery was about the same price - Nope! But saving $30 or more for a car battery and it lasting 4 + years is a good thing.

Since I'm not on CPAP yet, I don't know why anyone would need a battery except for backup power in the event of a power outage at home and I do understand that. Traveling with any size battery on a aircraft would be problematic considering everything you can't bring on board and how much stuff you may need to carry for a CPAP device. Traveling in a car or RV I would imagine size doesn't matter except to carry the battery. For sheer size a mobility battery would be good as is lithium but for duration a larger battery would be the best - no battery should be emptied to close to zero volts. The few mobility batteries I have seen were around $72 and 35 AH where the RV/marine battery (not from Walmart) I saw was about $81 and was 75 AH. Buying 2 35 AH batteries would cost more but I guess it would be easier to haul around a smaller battery or 2 smaller batteries than a large battery and I can see that as well. I don't live in an area that gets power outages often but I would certainly want a 75 AH battery over a 35 AH battery if I was concerned about power outages with the knowledge that I can still lift that 75 AH battery; if I couldn't then the 2 batteries would be the way to go.

Just my thoughts!

[ragtopcircus]

Sealed batteries still vent some gas through a pressure relief valve, but some of the hydrogen and oxygen gasses are recombined into water. There will still be some venting though, especially if the battery is overcharged.

Battery capacity is not like gasoline in a fuel tank. You can't use all of it, and the capacity is NOT fixed. Basically, the faster you drain the battery, the smaller the effective capacity becomes. However, there are some levers you can pull when designing the battery to optimize it for the intended usage. You will almost always get the best results by using the battery as it was intended. Scooter battery usage requirements happen to be a reasonable match for CPAP use.

If you insist on buying a marine battery, I would get one intended to power a trolling motor. A marine starting battery is not designed for a continuous load.

[babydinosnoreless]

Since I'm not on CPAP yet, I don't know why anyone would need a battery except for backup power in the event of a power outage at home and I do understand that.

While I personally don't get it (I'm a big fan of creature conforts) many people actually hike in to camping places or go mountain climbing or various other forms of "getting away" where bringing a big battery might not work.

[palerider]

\but I would certainly want a 75 AH battery over a 35 AH battery if I was concerned about power outages

a 35ah battery will give you about 5 nights without heat... which is good enough for most power outages... people that want extended runtime often add a solar panel for extended runtime.

Just my thoughts!

Just my thoughts!

[Biomed_ZZZ]

Since I'm not on CPAP yet, I don't know why anyone would need a battery except for backup power in the event of a power outage at home and I do understand that.

While I personally don't get it (I'm a big fan of creature conforts) many people actually hike in to camping places or go mountain climbing or various other forms of "getting away" where bringing a big battery might not work.

Interesting, I would't and didn't think of hiking or mountain climbing carrying a CPAP device with battery backup.