Marine battery versus battery pack?

[yardbird]

there are "fold out" solar panels that will trickle charge a battery all day long. Photovoltaics tend to be a bit spendy if you try getting too big.

Generators. I will never own another gasoline generator. And I won't go diesel either. If you have propane, put that generator on propane (VERY easy to do!) and you won't run out of gas, you won't varnish up the carburetor, you won't have "stale" gas because it hasn't been run in 6 months...

There are also devices you can use between your generator and your powered appliances, to ensure they are getting conditioned power. Generators typically generate based on RPMs. For nice even power you want to condition it a little first.

[CentralScrutinizer]

The smallest capacity battery that will get you by for a 8 hour sleep is about 12 amp hours... To recover that kind of power during a single period of day light you will likely need a solar panel that's at least 10 watts, more likely at least 15 watts. Panels able to put out that kind of power are about 3 feet long and a foot wide... Not something you could wear on your head, but possibly could attach to your backpack/back...

A 12 amp hour sealed lead acid battery weights about 10 pounds. A Lithium ION based battery pack like the Battery Geek C-150 weights about half of that. With each of these batteries when brand new would likely cover a full nights sleep for most CPAP users... They may come up a bit short if your pressure is higher then 12cmH2O or so... Basically these are the bare minimum sizes that would work for a full night of sleep on CPAP.

Draining a lead acid battery fully will shorten it's life span to probably no more then 300 cycles at best... and when fully empty will probably be quite hard to fully charge with a 15 watt solar panel.

Draining a Lithium ION battery pack fully probably doesn't hurt it too much but I'm not at all sure you can charge one of these with a 15 watt solar panel setup... I suspect that it will not work very well

So... I do think it would be VERY challenging to make recharge any battery that will power a CPAP device using a easily portable solar panel.

I also think that hiking for more then a couple days with a CPAP device would be very hard to do, unless your willing to carry a lot of weight. The CPAP itself probably weights 5 pounds, you need to figure at least 5 pounds per day for battery power (lithium based batteries will be the lightest)... Lithium batteries are also quite expensive when your talking about storing roughly 150 watts of total power per day... anything less then 150 watts will not get you a full nights sleep...

For the most part hiking with the intention of using CPAP would be difficult at best... One night might be somewhat practical... but for more then a couple days... it's probably not possible for most people.

[ColinP]

I also think that hiking for more then a couple days with a CPAP device would be very hard to do, unless your willing to carry a lot of weight. The CPAP itself probably weights 5 pounds, you need to figure at least 5 pounds per day for battery power (lithium based batteries will be the lightest)... Lithium batteries are also quite expensive when your talking about storing roughly 150 watts of total power per day... anything less then 150 watts will not get you a full nights sleep...

You raise some very good points, thanks. I agree that the weight will make it prohibitive. I'm also going to have to take up the slack from my kids by helping at least one of them with her kit, and I've got a lot more around my waist than last time I hiked. The other factor is that sleeping on the trail is not going to be good even with a CPAP, so I'm not going to loose out all that much by not having it.

If I was in my twenties and still capable of carrying a 30kg pack, I'd probbably give it a try (but then, money was tight in those days and I wouldn't have been able to pay for the kit lol).

Colin

[CentralScrutinizer]

Back to the original question... and/or when one has gotten to the point where Lead Acid Battery is decided upon as the battery of choice for a long time away from power... (in this case, it doesn't mean you will be a long way from a vehicle)...

I've been shopping for batteries... I want at least 40 AH or so... Hopefully more... maybe as much as 100 Amp hours... I know I can get a flooded cell battery for about $1/amp hour. However a sealed battery is a bit safer if/when you should decide to charge indoors, so I've been trying to find a good AGM or Gel battery at a decent price. Gel batteries would likely mean I need to buy a better charger (more expensive too) but have longer cycle life it seems if charged correctly. AGM I can probably get by with current charger, these are typically a little cheaper then Gel batteries, but cycle life isn't as good, but still probably slightly better then a flooded cell battery. I'd also like to stick with a battery that has good reputation and/or where you can get lots of info about it...

I've narrowed it down to a Deka brand AGM battery... I know I can get a group 24, 79AH battery for about $156 after shipping if figured in. So this is about $2/AH. Many AGM batteries are closer to $3/AH...

I can get a Optima D34M 55AH, localy (sams club) for about $155... or a Advanced Angler AGM 75AH battery (have a cabela's near me) for about $169... (both of these will have 6% sales tax added)

I like the Deka because the East Penn company has a very good reputation and they also have a lot of documentation for their batteries... Unfortunately I can't find these locally, so Ill have to mail order... I'm now trying to find the best price after shipping is added...

Part of me says just buy a flooded cell and charge it in the garage and run wires into my bed room...

[CentralScrutinizer]

Just a quick update on something I've just found... It's not a solution to the what to do when away from power issue, so much as it is a very interesting find I made while looking into battery chargers that might work well with Gel cell batteries...

I found a DC power supply and/or battery charger that also has the ability to perform as a 'uninterrupted' DC power supply. The device is a Samlex SEC-1215A 3 bank battery charger. It's not exactly cheep at around $150... but it can apparently safely charge flooded cell, AGM, and Gel type 12 volt batteries... can actually charge up to three such batteries at a time and also apparently has the ability to supply 12 volts DC output from that comes from it's switching power supply while AC power is supplied, while also supplying a 'float' charge to the battery... If the AC goes out, the output DC is then supplied by the battery...

My immediate needs are more for a DC UPS then for a battery power for a extended period without power... I'm very seriously considering buying one of these Samlex chargers and using the flooded deep cycle battery I already own in conjunction with it. I'm continuing to do research on the Samlex device, just to make sure it's really going to do what I want it to do...

FYI, I own another Samlex DC power source which I've had for about 5 years... So, I have little or no doubt about the quality of the products they make... I just never realized they made a fancy system like this SEC-1215A charger system until just today...

[Pineapple]

Central,

The Samlex sounds vaguely familar. Did you look at this link?

viewtopic.php?t=29890

I'm not an EE, but if you're looking to go that way, this might be something more to look into.

[CentralScrutinizer]

I've read most of what I could find on this site about battery power and/or UPS systems. I've not found anything about the Samlex device here. (even did a google search for samlex and/or specifically looking for it at this site and it yields nothing.

Ham Radio guys know all about Samlex and/or many of their products are geared toward Ham Radio... (I'm not a Ham radio guy, I have used their power supplies to supply DC voltage to Radio Controlled Car battery chargers)

The standard stuff that's been discussed on this and other CPAP fourms, for back up power for CPAP hasn't interested me too much, for a variety of reasons. I'll try and list some of these... Standard AC UPS (typically used for computers) are too expensive if you want to power a device for more then a few minutes. DC 'jump start' type systems are cheaper, but may struggle to give you a full night's backup, and certainly won't power you for days...

I'm trying to kill two CPAP problems with one stone to some degree... I want to run my CPAP at home on a system that is fully capable of running on battery for at least 8 hours in the event of a power failure. (if the system could run for several days without power, even better) I want the system to switch over to battery automatically, or constantly run on battery and also recharge the battery every day. The second part I'm trying to cover is a need for a system to take with me to a week long fishing trip, where power is supplied by generator and that generator is only run during the daytime for about 6 to 8 hours a day. (once in the morning for about 3 hours and once again in the evening for a few hours, and I don't control this generator, it's supplied by the camp I stay at)

At this point, the Samlex device is looking like it may do exactly what I want... and more. I had not dreamed of being able to connect 3 batteries at once and figured I was really going to be pushing things trying to get everything recharged in 6 hours at the fishing camp using the charger I had been considering and/or already have..

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CPAPopedia Keywords Contained In This Post (Click For Definition): CPAP, Power

[compton]

I have a resmed s8 escape cpap machine and i purchased a portable battery source from sears store in thier automotive dept. The cost was $119 dollars it has outlet plugs and d/c 12volt plugs built in, in addition i purchased a resmed d/c converter for $79 to regulate power spikes. I used it for 2 nites (17hrs).and it still had 40% power left on the battery lcd screen. The 1150 portable battery power weighs about 13 lbs. and has a built in carrying handle it also has a built in lite and air compressor and it will jump start your veh. My cpap mach. is set at 11 and i dont use the humidifier. I hope this imformation will help someone who like me did not like the idea of spending 400dollars for a decent power source. I only used the d/c plugs since the resmed d/c converter plugs into the battery and then you connect your cpap machine to the resmed d/c converter. You can power cellphones , dvd players and many other things with this unit. I believe the d/c converter is useful even though i didnt like $79 price tag, but i would rather protect my mach. from possible power spikes.good luck from Compton campin in Connecticut.

[Pineapple]

Thank you Compton.

Central,

If you do go with the Samlex, after your first outing post how it worked for you. Many of us will be all ears to hear your review.

[CentralScrutinizer]

Yes... if I do go with the Samlex thing I will be sure to make full report of how it all worked out...

I spoke with a co-worker who IS a ham radio buff... asked him if he'd ever tried to buy a DC UPS, etc... He told me about a product sold by a company called 'Jetstream' model # JTPS14BCM , which costs around $59 and theoretically does something very similar to the much more expensive Samlex product... However, I can't find any good documentation for it.

I'm a bit of a gadget freak and I really like the specs and/or all the info that the Samlex has about it's operation... I'm very tempted to get the Samlex partly from pure curiosity... It pretty clearly has way more features then the much cheaper Jetstream product. (faster charging, selectable charge voltages and such to work correctly with different battery types, etc...)

[CentralScrutinizer]

The gadget freak in me has gotten the best of me... I just ordered a Samlex SEC-1215A from Ham Radio Outlet... ($120 free shipping). I guess it may take up to 10 days to get it... so it may be a while before I have much else to say about this thing... I'll likely start a new thread when I get it connected and have some experience with it... I've got some in-home wiring I'll need to do in the mean time...

[pjwalman]

Compton, that Sears unit sounds exactly like what I'll need for the RV. Thank you! So it has a regular plug-in type outlet on it, so you can plug it in just as if you were at home? You don't need a cigarette lighter hookup. Right? (Sorry to sound stupid -- this area is certainly not my strong suit.)

Do you happen to have a model or part number or a more specific name for it so I'll know what to ask for?

Peggy

[Snoredog]

Anyone have experience to share about whether a marine battery or a battery pack works best with an M Auto, which is more convenient, which gives a longer use time, other things I may not have thought about? We occasional take the RV to places that don't have power. I bought the doohicky that has the cigarette lighter and the ends for a battery, but my husband says our generator wouldn't support the CPAP all night (plus there's no cigarette lighter anywhere near the bed), so it looks like I either have to invest in a marine battery or battery pack like those sold on cpap.com. Looks, though, like the cheaper ones ($269) only would last about seven hours so wouldn't last a whole weekend of camping and the super batteries that provide 20 hours are $450, which hits a little at my "cheap button". How long would a marine battery last for an APAP range of 10-14, if anyone knows? And (typical dumb woman question -- sorry), do those have just so many hours of battery life to them or do you have to charge them in some way, too?

Thanks for your input!

Peggy

A marine battery simply has thicker plates so it lasts longer than a conventional automotive battery. Instead of spending extra for a marine battery I would just get a automotive battery, you can get one for a 2003 VW Beetle at Kragen/Checkers for $89 bucks and it will come with a 84-month warranty, your CPAP will die before that battery does.

A battery loses recovery life the more times it has been run completely dead, that will never happen with a CPAP machine, it will shut off before the battery ever runs down that low because it won't be able to maintain pressure.

A marine battery is able to survive more cycles because the plates inside are thicker but the design is the same.

What I suggest if you are using your machine in the RV is:

-buy a good automotive battery like the Autolite from Kragen/Checkers the one that fits a Beetle above is fairly small puts out 680 CCA (runs my kids 200-watt Monsoon car stereo all day long with hip-hop)
-put the battery on a battery "isolator" which cost about $30 bucks also at Kragen/Checkers autoparts

Very simple to hook up, the battery isolator will isolate the CPAP battery from the RV batteries so it won't back feed to it and drain any other batteries, yet the battery will automatically recharge anytime you run your generator or plug into street power in which the RV's inverter should provide 12-volts to recharge your CPAP battery.

That battery is also small enough should you decide to use it camping in a tent it will run your M series 3 or more nights with ease.

I would get a cigarette lighter adaptor for the M series, one from Radio Shack works just fine if you replace the fuse it comes with using a higher 3AMP rated fuse.

Have your husband install a cigarette lighter "socket" from Radio Shack on your side of the bed if you don't have one, it would run to that battery in the RV's battery box.

So for about $120 and a little bit of work you can have a setup that will keep you running 3-4 nights or longer even if it never gets charged.

[CentralScrutinizer]

Technically speaking (or perhaps morally speaking) I don't believe the automotive battery warranty would cover use in a installation other then automobile... Here is some text from a Parts America

"A battery that fails because of improper installation, another faulty part, low fluid levels or other abuse is not covered by this warranty. Warranty does not apply to non-marine batteries installed in marine applications.'

I would say that installing a automotive battery in anything other then a automobile where it was intended to be used for typical automobile type uses, such as starting the car, and the occasional other use for supplying power to devices in the car... would basically qualify as not being properly installed.

Having said that, it would be hard to prove you had not used the battery in a car if you simply carry the battery in to a store for a warranty replacement, etc...

But anyway, snoredog is probably correct that for occasional use to power a CPAP device for a few days, a good car battery probably will work almost as good as any other lead acid battery would.

There are many issues to consider with regard to all of this however... One is safety... One would also be just how often you plan on needing power for CPAP when AC power is not readily available.

All lead acid batteries should be charged periodically... that is leaving a battery at levels far bellow their fully charged state can cause sulfation, which will reduce the batteries capacity and/our output.

Deep discharge of a battery not intended for it will cause damage as well... as I understand it, parts of the lead plates will start to deteriorate and/or small pieces will fall off the plates. This eventually causes reduced capacity and/or can even lead to complete battery failure.

All of this can get complex and/or hard to fully understand, particularly for the person who doesn't really care to know all of this kind of stuff...

Exactly what the best thing to do is... could probably be debated till pigs fly...

I personally have been using and/or destroying all types of batteries for years... I've had some lead acid batteries work for many many years, others that lasted less then two years... Part of me, says just buy the cheapest battery you can get and just replace it when it goes bad... I say that because I've have some batteries last for many years even when they were basically abused... other batteries died a vary early death even when they were treated with respect and or as you should treat them... Some of the longest lasting batteries I've owned were also the cheapest... (but not always). I had one Kirtland (costco lable) that lasted about 6 years where I basically abused it by not charging it regularly and deeply discharging it when I did use it... I've had other 'brand' names last no more then two even when taken good care of... So... yeah, part of me says just buy cheap and often (if it does fail).

[CentralScrutinizer]

Oh... I forgot to mention the part about safety... I've never had a battery blow up on me... but do know folks who have had them blow up...

Sealed type lead acid batteries are a bit safer then non sealed... Sealed types are sometimes called 'maintenance free'. Most car batteries are not sealed and/or are theoretically slightly more at risk for causing a explosion. Many possibly most 'deep cycle' batteries are also not sealed and at higher risk for explosion...

Sealed batteries are usually called either AGM or Gel... but there are also sealed batteries that are 'flooded' however these are less common.

Non sealed batteries tend to let off more hydrogen gas during 'normal' operation then do sealed batteries(sealed batteries may not put out any if used and/or charged correctly)... and as you may know if you've ever seen the Hindenburg disaster film footage... can be very flammable. (it's also lighter then air, which means it will tend to rise)

Sealed batteries are sealed... the hydrogen gas they also produce stays within the sealed structure of the battery itself and/or recombines with the battery materials under normal operation. However if you overcharge these, they too will vent hydrogen gas... There are other abnormal conditions that could lead to explosions of sealed batteries too, so while they tend to be safer then non sealed batteries, they are not 100% safe either...

Most UPS and/or battery 'jump start' devices use sealed type batteries and/or have been designed to be relatively safe... When you start getting into home made solutions with or without sealed batteries, you yourself bare all the risk... the risk may be very low if you know what your doing and follow safety practices... or may be very high if your not very bright.