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SleepyEyes21 wrote:

CapnLoki wrote:...see the last post in this thread:
viewtopic.php?t=102775

Hi CapnLoki, I live on the east coast of Florida and we lost power for two weeks in 2004 when all the last big set of hurricanes came through. Fortunately, this was pre-cpap years for me, however I am preparing now that I need to. I did read your last post in this thread. I currently have a PR System One Auto 560P; titration averages at 8. I do not use the heated humidifier in summer months. Assuming I sleep an average of 8 hours per night, my questions are:

1. If I were to purchase the scooter size battery, they need electricity for recharge, correct? And they only last for 1-2 nights?

As it turns out, I measured the usage on my 560 in various configurations, with an average pressure of 9.2. The results are here:
viewtopic.php?t=102179
Without humidity, it uses 4 Amp-hours a night. This has been confirmed by about 200 nights running on battery, plus other reports. The scooter batteries (size U1) are 35 Amp-hours, but you shouldn't totally discharge them, so you should think of them as about 25 AH with a 10 AH reserve. If you follow that protocol the lifetime will be 100's of cycles, rather than dozens.

This means about 6 nights on a scooter battery if you don't use humidity. (BTW, when I visit my father in Boca I don't bother bringing the humidifier.)

SleepyEyes21 wrote:2. How long/ how many nights would a deep cycle marine battery last, and is there a particular size/ type/brand you would recommend?

You can use any deep cycle battery to achieve the capacity you want, but be careful with "marine" since there are also starting batteries which are marine but not deep cycle. Also, the term "marine" comes with a 100% price inflation - West Marine sells a U1 AGM for $150 that you can get on Amazon for $65. Also, although you can get a big 100 AH flooded (often dubbed "maintenance free" which means you throw them out after several years) from Walmart for under $100, I greatly prefer the smaller scooter batteries that are truly "bedroom safe." If you're really concerned about long outages, you might consider getting two smaller batteries. If you want a big battery you can search Amazon for an AGM. This was my first hit:
http://www.amazon.com/100Ah-SOLAR-WIND- ... B00S1RT58C

SleepyEyes21 wrote:3. Can a deep cycle battery be recharged from a car battery or how are they recharged?

Yes but it doesn't really work that well. You can fairly easily recharge from a running car, though it is a bit tedious. It will take about an hour to recharge from 50% down up to 15% down. Topping off takes several hours more. This is true for any lead-acid based battery assuming the alternator is big enough.

SleepyEyes21 wrote:4. I don't have the 12 volt connector for my PR yet, so what else would I need to purchase and where can I get it? (hardware store vs. camping store, etc.)

Thank you!

The link at the top describes my favorite charger and the several extra bits of cable you'll need. For the basic setup you want to think carefully about putting it together, but then its foolproof in use. If you get into multiple batteries and charging from the car, you need to take extra care.

I use lithium ion travel battery, just mentioning this to show I have researched this topic. But....... I was pretty amazed when my buddy used his car battery, and one of those cheesy cigarette lighter inverters, an extention cord from his truck cab to his tent for four nights. This was in baja, we did a 3 mile roundtrip daily for ice, no more charging than that. On the last day leaving, his truck did start but took a few seconds. lol If I lived somewhere where weather might take power out, I'd invest in 1 or 2 deep cycle marine batteries with inverter (if needed by your machine).

It was literaly something like this.

http://www.homedepot.com/p/CyberPower-S ... lsrc=aw.ds

Dive Apnea wrote:I use lithium ion travel battery, just mentioning this to show I have researched this topic. But....... I was pretty amazed when my buddy used his car battery, and one of those cheesy cigarette lighter inverters, an extention cord from his truck cab to his tent for four nights. This was in baja, we did a 3 mile roundtrip daily for ice, no more charging than that. On the last day leaving, his truck did start but took a few seconds. lol If I lived somewhere where weather might take power out, I'd invest in 1 or 2 deep cycle marine batteries with inverter (if needed by your machine).

It was literaly something like this.

http://www.homedepot.com/p/CyberPower-S ... lsrc=aw.ds

You probably already know this, but I'll explain for the benefit of others: this is BAD practice! The starting battery may start with 100 Amp-hour capacity, but unlike deep cycle batteries, they are considered depleted for starting purposes when at 70% State of Charge, or down only 30 Amp-hours. The cpap (without humidity) uses about 5 AH a night, but double that to 10 for the inverter. Three minutes will only recharge a couple of AH (if that) so after 4 nights, the battery will be marginal for starting. An old battery, or a cold night, could easily push it over the edge. And of course using a humidifier makes this much worse.

Using a starting battery for one night followed by a lengthy drive will probably work out OK with no lasting ill effects, but using it a number of nights without recharge is foolish, especially when a proper deep cycle can be had for well under a $100.

CapnLoki wrote:

Dive Apnea wrote:I use lithium ion travel battery, just mentioning this to show I have researched this topic. But....... I was pretty amazed when my buddy used his car battery, and one of those cheesy cigarette lighter inverters, an extention cord from his truck cab to his tent for four nights. This was in baja, we did a 3 mile roundtrip daily for ice, no more charging than that. On the last day leaving, his truck did start but took a few seconds. lol If I lived somewhere where weather might take power out, I'd invest in 1 or 2 deep cycle marine batteries with inverter (if needed by your machine).

It was literaly something like this.

http://www.homedepot.com/p/CyberPower-S ... lsrc=aw.ds

You probably already know this, but I'll explain for the benefit of others: this is BAD practice! The starting battery may start with 100 Amp-hour capacity, but unlike deep cycle batteries, they are considered depleted for starting purposes when at 70% State of Charge, or down only 30 Amp-hours. The cpap (without humidity) uses about 5 AH a night, but double that to 10 for the inverter. Three minutes will only recharge a couple of AH (if that) so after 4 nights, the battery will be marginal for starting. An old battery, or a cold night, could easily push it over the edge. And of course using a humidifier makes this much worse.

Using a starting battery for one night followed by a lengthy drive will probably work out OK with no lasting ill effects, but using it a number of nights without recharge is foolish, especially when a proper deep cycle can be had for well under a $100.

+1

I use deep cycle batteries when I go into Australia's wonderful Outback to power my fridge and lights. You can punish a deep cycle battery (but never below 50%) Do that with your starter battery and it will die very quickly.

A few more thoughts on this topic ...

Dive Apnea wrote:... my buddy used his car battery, and one of those cheesy cigarette lighter inverters ... It was literally something like this.
http://www.homedepot.com/p/CyberPower-S ... lsrc=aw.ds

These inverters are crude but effective. However, I've found that the failure rate of under $25 inverters to be high so I wouldn't want to rely on them. Also, the efficiency is going to be low, certainly no better than 60% and possibly much worse. In addition, they tend to use a noisy fan.

I have been looking for years for a small, high efficiency inverter that could be used for chargers like electric toothbrushes, etc. It seems like all the quality inverters are several hundred watts or more, and these won't be efficient at putting out 10 watts and certainly not at 1 watt. If anyone knows where to find one (or make one) I'd like to hear about it.

Holden4th wrote:I use deep cycle batteries when I go into Australia's wonderful Outback to power my fridge and lights. You can punish a deep cycle battery (but never below 50%) Do that with your starter battery and it will die very quickly.

A quality deep cycle can be pushed further then 50% but at the cost of limiting lifetime. For example, I try to never go below 50% (often not even that) with my boat batteries which I expect to last 6-7 years, or close to a thousand cycles. On the other hand, many cpap users need the battery for one vacation a year plus the occasional power failure. For this use pushing to 80% is reasonable. You might expect 200 cycles of 80%, 500 of 50%, or over a thousand if its only discharged 30%.

And as I mentioned, using a starting battery for one night is not a total disaster, you just have to understand that the deep cycle life of a starting battery is measured in the dozens, and an older battery may only have 1 or 2 of those left.

CapnLoki wrote:Using a starting battery for one night followed by a lengthy drive will probably work out OK with no lasting ill effects, but using it a number of nights without recharge is foolish, especially when a proper deep cycle can be had for well under a $100.

I agree which is why I use lith ion battery and solar charger from cpap.com, and if I lived somewhere with weather, I'd have at least two deep cycles on trickle charge. I asked how his car battery is doing, he said just fine. Just passing some info, maybe like you say cig lighter with car battery for an emergency.

CapnLoki wrote:

SleepyEyes21 wrote:

CapnLoki wrote:...see the last post in this thread:
viewtopic.php?t=102775

Hi CapnLoki, I live on the east coast of Florida and we lost power for two weeks in 2004 when all the last big set of hurricanes came through. Fortunately, this was pre-cpap years for me, however I am preparing now that I need to. I did read your last post in this thread. I currently have a PR System One Auto 560P; titration averages at 8. I do not use the heated humidifier in summer months. Assuming I sleep an average of 8 hours per night, my questions are:

1. If I were to purchase the scooter size battery, they need electricity for recharge, correct? And they only last for 1-2 nights?

As it turns out, I measured the usage on my 560 in various configurations, with an average pressure of 9.2. The results are here:
viewtopic.php?t=102179
Without humidity, it uses 4 Amp-hours a night. This has been confirmed by about 200 nights running on battery, plus other reports. The scooter batteries (size U1) are 35 Amp-hours, but you shouldn't totally discharge them, so you should think of them as about 25 AH with a 10 AH reserve. If you follow that protocol the lifetime will be 100's of cycles, rather than dozens.

This means about 6 nights on a scooter battery if you don't use humidity. (BTW, when I visit my father in Boca I don't bother bringing the humidifier.)

SleepyEyes21 wrote:2. How long/ how many nights would a deep cycle marine battery last, and is there a particular size/ type/brand you would recommend?

You can use any deep cycle battery to achieve the capacity you want, but be careful with "marine" since there are also starting batteries which are marine but not deep cycle. Also, the term "marine" comes with a 100% price inflation - West Marine sells a U1 AGM for $150 that you can get on Amazon for $65. Also, although you can get a big 100 AH flooded (often dubbed "maintenance free" which means you throw them out after several years) from Walmart for under $100, I greatly prefer the smaller scooter batteries that are truly "bedroom safe." If you're really concerned about long outages, you might consider getting two smaller batteries. If you want a big battery you can search Amazon for an AGM. This was my first hit:
http://www.amazon.com/100Ah-SOLAR-WIND- ... B00S1RT58C

SleepyEyes21 wrote:3. Can a deep cycle battery be recharged from a car battery or how are they recharged?

Yes but it doesn't really work that well. You can fairly easily recharge from a running car, though it is a bit tedious. It will take about an hour to recharge from 50% down up to 15% down. Topping off takes several hours more. This is true for any lead-acid based battery assuming the alternator is big enough.

SleepyEyes21 wrote:4. I don't have the 12 volt connector for my PR yet, so what else would I need to purchase and where can I get it? (hardware store vs. camping store, etc.)

Thank you!

The link at the top describes my favorite charger and the several extra bits of cable you'll need. For the basic setup you want to think carefully about putting it together, but then its foolproof in use. If you get into multiple batteries and charging from the car, you need to take extra care.

Thanks so much for all the info, CapnLoki! I went back and re-studied your recommendations, and I'd rather go with the scooter battery than a larger, heavier battery. Thanks also, for the tips on the 'marine' deep cycle and 'maintenance-free' advertising; good to know

In your original post where you listed the optimal parts needed to go with a battery, under the Cables section- you stated " The Battery Tender comes with almost everything including fuses (get spares) but you'll need a "cigarette lighter socket"..." I went to the Amazon link to look at this product and it does not say that any fuses come with the battery tender. Can you please update your post to include anything that else that is supposed to come with the battery tender?

I thank you kindly, sir

I have recently learned that car batteries are engineered to provide a quick surge of energy to start the motor and engineered to be immediately recharged. They may go way down if used over a long time and it may reduce the life of that battery.
"Marine" batteries are engineered to continue to put out juice over a number of hours. Of course, they need to be recharged as well.
I am dealing with this whole dilemma so I can go camping away from any AC source.
Any other good ideas out there would be most welcome.

kencrab wrote:I have recently learned that car batteries are engineered to provide a quick surge of energy to start the motor and engineered to be immediately recharged. They may go way down if used over a long time and it may reduce the life of that battery.
"Marine" batteries are engineered to continue to put out juice over a number of hours. Of course, they need to be recharged as well.
I am dealing with this whole dilemma so I can go camping away from any AC source.
Any other good ideas out there would be most welcome.

You are correct the starting batteries are not a good choice for powering a cpap. Many "marine" batteries are appropriate, but they must be labeled as "deep cycle" or at least "dual purpose" as there are many marine batteries that are starting batteries. Also, the term "marine" often comes with a 100% surcharge, so you do best looking for "deep cycle."

There are many posts here that address camping with a cpap. If you set up an account and enter your equipment, we'll know how best to advise you, Also, it helps to know what type of camping you're doing, and how long you'll be out.

SleepyEyes21 wrote: ...
In your original post where you listed the optimal parts needed to go with a battery, under the Cables section- you stated " The Battery Tender comes with almost everything including fuses (get spares) but you'll need a "cigarette lighter socket"..." I went to the Amazon link to look at this product and it does not say that any fuses come with the battery tender. Can you please update your post to include anything that else that is supposed to come with the battery tender?

I thank you kindly, sir

I've updated the original post to include a link to maker's site
http://www.batterytender.com/Dion/Batte ... -Plus.html
Hopefully Amazon ships the same accesories, as the part number is the same. As noted, a cigarette socket is needed to match the plug from the Respironics DC cable, and a 5 to 1 splitter is handy to connect the charger at the same time do it can be used in UPS more. Also, you may want to add cell phone chargers, etc. These can all be had from Amazon at a modest cost.

CapnLoki wrote:

SleepyEyes21 wrote: ...
In your original post where you listed the optimal parts needed to go with a battery, under the Cables section- you stated " The Battery Tender comes with almost everything including fuses (get spares) but you'll need a "cigarette lighter socket"..." I went to the Amazon link to look at this product and it does not say that any fuses come with the battery tender. Can you please update your post to include anything that else that is supposed to come with the battery tender?

I thank you kindly, sir

I've updated the original post to include a link to maker's site
http://www.batterytender.com/Dion/Batte ... -Plus.html
Hopefully Amazon ships the same accesories, as the part number is the same. As noted, a cigarette socket is needed to match the plug from the Respironics DC cable, and a 5 to 1 splitter is handy to connect the charger at the same time do it can be used in UPS more. Also, you may want to add cell phone chargers, etc. These can all be had from Amazon at a modest cost.

Thanks again, CapnLoki- I've seen most of these parts on Amazon while searching for the items on your list. Starting to see the need for extra adapters