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Be aware that current LiFePO4 batteries do not have the claimed amp-hour ratings when used for constant draw applications. The manufacturers are using a lead equivalent amp hours based on the fact the batteries are capable of much faster discharge under staring conditions. The real amp hour rating of the battery is about 1/3 the claimed amp hours. So this 10 amp-hour battery is less than 4 amp hours in real use. This will not power a device long enough. They are expensive, and can be damaged if the recharge rate is too fast.

Sleeprider wrote:Be aware that current LiFePO4 batteries do not have the claimed amp-hour ratings when used for constant draw applications. The manufacturers are using a lead equivalent amp hours based on the fact the batteries are capable of much faster discharge under staring conditions. The real amp hour rating of the battery is about 1/3 the claimed amp hours. So this 10 amp-hour battery is less than 4 amp hours in real use. This will not power a device long enough. They are expensive, and can be damaged if the recharge rate is too fast.

This is definitely true for those batteries sold as "starting batteries" (often for motorcycles and PWCs) which are often listed as having "Pb Equivalent" power. Deltran (Battery Tender) advises that these should not be used in deep cycle applications at all (same as lead starting batteries). Most LiFePO4 batteries not sold in the motorcycle market have honest Amp-Hour ratings. Its fairly easy to double check by looking at the weight and dimensions because they are all made from the same 2 or 3 basic cell types. In fact, you can buy these cells loose, or assembled in packs, with the BMS chips, if you really want to save a few bucks and know exactly what you're getting.

Both of the batteries I mention (the 10AH and the 20AH) are are claiming true Amp-Hours, not "equivalent." You can track down the full specs from the manufacturers. I did notice that the 10AH is called a "starting battery" in one spec, but then claims its good for mobility and medical applications, and can handle "thousands of cycles, 100% DOD" (depth of discharge). This sounds a lot like a deep cycle battery. You really should do your homework before making claims of deception.
http://www.vision-batt.com/product_view ... d=9&tid=13
http://www.ctcbattery.com/LiFePO4-Recha ... le-Battery

I've been happy with my owell industries 12 C 266 for backpacking, boating, flying etc.
4 nights at 9cm/hr.
Good luck

CapnLoki wrote:

Sleeprider wrote:Be aware that current LiFePO4 batteries do not have the claimed amp-hour ratings when used for constant draw applications. The manufacturers are using a lead equivalent amp hours based on the fact the batteries are capable of much faster discharge under staring conditions. The real amp hour rating of the battery is about 1/3 the claimed amp hours. So this 10 amp-hour battery is less than 4 amp hours in real use. This will not power a device long enough. They are expensive, and can be damaged if the recharge rate is too fast.

This is definitely true for those batteries sold as "starting batteries" (often for motorcycles and PWCs) which are often listed as having "Pb Equivalent" power. Deltran (Battery Tender) advises that these should not be used in deep cycle applications at all (same as lead starting batteries). Most LiFePO4 batteries not sold in the motorcycle market have honest Amp-Hour ratings. Its fairly easy to double check by looking at the weight and dimensions because they are all made from the same 2 or 3 basic cell types. In fact, you can buy these cells loose, or assembled in packs, with the BMS chips, if you really want to save a few bucks and know exactly what you're getting.

Both of the batteries I mention (the 10AH and the 20AH) are are claiming true Amp-Hours, not "equivalent." You can track down the full specs from the manufacturers. I did notice that the 10AH is called a "starting battery" in one spec, but then claims its good for mobility and medical applications, and can handle "thousands of cycles, 100% DOD" (depth of discharge). This sounds a lot like a deep cycle battery. You really should do your homework before making claims of deception.
http://www.vision-batt.com/product_view ... d=9&tid=13
http://www.ctcbattery.com/LiFePO4-Recha ... le-Battery

I was unable to find the detailed specifications of the battery you linked at Amazon. My concern about many batteries being rated as Pb/Eq may not apply to these, however, offhand, they are of a price and size that raised that concern. I will not assume this battery delivers 19+ amp hours unless I see independent testing data and specs that prove it. The inaccurate reporting of capacity is very prevalent amongst LiFePO4 battery manufacturers and worth being aware of. In any event, my comments are generally applicable to this class of battery and not a claim this battery mfg is engaging in deception. As a class, the entire LiFePO4 world is suspect in their claims.

Awesome thread! Basically, I've been using a Black & Decker Electromate 400 w/ a generic solar panel (20 watts or about 1 amp per hour) for about many years now for boy/cub scout camping. With solar charging during the day I've make it just fine through (2) 5 night summer camps and 20+ weekend campouts. The problem is that now we're starting to look at backpacking campouts and our summer camp this year is "high adventure" and we'll be hiking to different campsites every night. The Electromate weighs 25 lbs and the solar panel is 24"x12"

After reading this thread and the linked threads, I'm on the fence about the Poweradd vs the LiFePO4 battery such as this (http://www.amazon.com/Battery-Tender-BT ... 1BSN6F5G78).

Surprisingly, they are about the same size and weight. I would need to get some sort of container for the LiFePO4 to have in my pack.

The big concern I have is if I can charge either one of these from solar. I know I have to get a smaller solar panel, but I'm trying to figure out how to hook them up.

I *think* with the LiFePO4 battery, I can just hook up a pos and neg straight to the solar panel (alligator clips or cigarette lighter adapters which I already have). To use this battery, I have the 12 volt adapter for my s9, and alligator clips to cigarette female adapter to connect to the battery.

For the Poweradd, I'd need to fabricate a coax to cigarette lighter female to run the s9, like finster did with the s8. Also, I'm not sure how to charge it. It looks like it uses a coax input, I guess I'd need to fabricate a coax input to whatever the solar panel output is.

In short it looks like the LiFePO4 battery would be easier to implement, and is a little cheaper. Any thoughts or opinions would be appreciated!

For solar panels, I'm also looking at http://www.amazon.com/Instapark%C2%AE-M ... B00EVFEBKU. Basically, the s9 uses around 8 ah a night (using numbers from my old s8, I should probably re-calculate it all).

Any thoughts or suggestions about the solar panel would be welcome also

I decided on the PowerAdd Pro 32000. I bought a wired 2.5mm barrel connector for the dc out at a local electronics shop and spliced it into a female cigarette lighter adapter that I already had. Total cost was $3.26. There's one on amazon for around $10.
The set up is:
PowerAdd Pro 32000 --> fabricated 2.5mm to Cigararette --> Resmed 12volt converter --> Resmed S9 elite.
I have a setting of "11", turned off EPR, a 5 minute ramp, and am not using humidifier.

I used it for the first night for about 5.5 hours (work called about 1am, so it's an estimate) and used 35%
The second night, I used it for 7 hours and used 39%

After both nights, it was at 25%, which I consider a successful test! I'm going car camping this weekend and will try it out.

I also decided to get weights since I'll be backpacking this summer.
Old setup (jumpstarter, adapters, S9, mask, tube): 23.5 lbs
New setup (poweradd, adapters, S9, mask, tube): 6.7 lbs

The input charge voltage of the poweradd is 14-19 volts, so I'll need a different solar panel. I'm eyeing one over now, but not in a super big hurry yet.

Excellent news flyswatta!

Glad It worked out for you!

Would the poweradd be able to run a IntelliPAP AutoAdjust https://www.cpap.com/productpage/devilb ... chine.html?

It should.

The only thing that is unknown is if the PowerAdd has a connection that will fit the IntelliPAP.

If it doesn't have a connection that will fit, you can make your own using the Devilbiss 12v adaptor.

Let us know how it works out for you, by posting an update.

PowerAdd came in today. Tested it on my M Series Auto CPAP @12V and 20cm h2o (auto off). It fired up then shut down with the poweradd volt blinking. Set the poweradd to 16V and the CPAP fired up and started operating like normal!

Going to test tonight. If the M Auto works, I think I'll just use that for my backpack/travel kit.

kiapolo wrote:PowerAdd came in today. Tested it on my M Series Auto CPAP @12V and 20cm h2o (auto off).

Ran it last night for about 5 hours. When I shut it off battery was at 43%.

Excellent!

Went backpacking last weekend. Used it for two nights. The PowerAdd was at 24% after the two nights.

Really glad to have found a CPAP solution that works for hiking and camping!!!

Awesome! I forgot to mention that I went camping two weeks ago. The Poweradd worked great for two nights - a 6 hour night and a 10 hour night and I was at 14%.

I ordered the AllPowers 28 watt portable solar panels and will try them out in two weeks at my next camp out. For a test, it charged the Poweradd about 20% in 3 hours. I can't wait to see what it does on a camp out!

http://www.amazon.com/gp/product/B00G6C ... UTF8&psc=1

Tweaked my setting using a M Cpap (non-auto...with my Cpap setting at 18, I was able to sleep for ~5 hours and the poweradd went to 53% (good enough for two nights of hiking/backpacking sleep).

I bought a USB to DC-M connector to see if I could possible trickle charge my poweradd with my 14W (5V/2A) solar charger.

Please keep me posted on what works with the solar panels.

I can see them coming in handy for multiple day camping.