My back up power set up questions UPDATE

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sleep_quest
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My back up power set up questions UPDATE

Post by sleep_quest » Mon Oct 06, 2014 5:11 pm

I didn't want to hijack the other thread with my specific questions so I started my own thread:

raftergirl said:
Here's another alternative. I was given this link by another rafter who uses CPAP. These batteries might be a good compromise. Not quite as expensive as the Li Ion, but much lighter and slightly smaller than my Deep Cycle AGM. 6.6 lb. for the 12V20A vs mine at 13 lb. Another plus is that they are much better suited to being discharged below 50% vs the AGM batteries, and they have a much longer lifetime of charging. I might think about one of these in the 12A version (3 lb.) for my kayak touring where I definitely need a smaller & lighter battery. Perhaps I'll replace all my AGM with these in the future????

http://store.starkpower.com/Energy-Stor ... _c_21.html


I'll admit my ignorance right up front...I've been following the various backup power posts with the hope of finding just the right set up that would work for me at home however, I get glassy eyed with some of the technical jargon. To put it plainly, I get that a higher amp hour back up source will last longer than lower amp hour ones. I also get that there are many options with varying amounts of effort/skill needed to build them: back up unit from CPAP.com, deep cycle marine battery, lithium ion battery, car jump starter, UPS etc. TOO Many Options have my head spinning and I don't want to solder, weld, wire, or otherwise construct my back up power solution. My ultimate set up would last more than a few days (I live in earthquake country), be easy to set up (keep those "caution! make sure you have your positive/negative cables in the right place lest you blow up your CPAP machine and who knows what else" warnings to a minimum), be safe indoors, and be cost efficient. Think plug and play...not a lot to ask, right?

I currently have a new model Duracell DR600PWR 18Ah powerpack bedside and I've purchased the Shielded DC Cord for PR System One 60 Series Machines and the Respironics, 12volt DC Battery Adapter Cable with Battery Clips so that I have the option of hooking up to a deep cycle battery in the future. Aside from hooking the CPAP up directly to the deep cycle battery, does it make sense to pigtail (is that the right word?) the Duracell powerpack via the built in jumper cables to the deep cycle battery for charging/longer CPAP run time in the event of a long term power outage? My thought is this solution will give me several different options if it will work. I'll have the powerpack to use directly with my CPAP for short term use (it has a single DC and 2 AC outlets plus 2 USB ports which can also be used with other electronic devices), and then I can charge the powerpack using the deep cycle battery and use each separately as well as pigtail the two together for a longer term electrical source. Does this make sense and will it work as I describe?

If it works what about the safety of having the Lithium Iron Phosphate battery stored next to my bed vs. a lead acid battery and the issue with gasses emanating/acid spilling from it. Per the StarkPower website "LiFePO4 contains no poisonous lead, no acid, and does not create gasses during charge, as traditional Lead-Acid batteries do." Does this mean a battery box used to seal a deep cycle battery is not necessary with a LiFePO4? Are there any concerns regarding LiFePO4 batteries to be aware of? What are the trade offs between the two types of batteries besides initial cost, battery weight and potential poisonous gasses? The website (see link above) makes the LiFePO4 sound great compared to lead acid batteries but how much of that is advertising or can these features be considered fact?

If I buy a 12Ah battery and I'm only powering my PRS1 560 without the humidifier (Pressure: APAP 9.0 min/15 max) how many hours can I expect from the different configurations of this setup assuming the source is fully charged (sorry, math is not my strong suit)?
CPAP connected to powerpack standalone via AC?
CPAP connected to powerpack standalone via DC?
CPAP connected via 12volt DC Battery Adapter Cable with Battery Clips to lead acid deep cycle battery
CPAP connected via 12volt DC Battery Adapter Cable with Battery Clips to LiFePO4
CPAP connected to powerpack via DC and powerpack is pigtailed to lead acid deep cycle battery
CPAP connected to powerpack via DC and powerpack is pigtailed to LiFePO4
How many times can the powerpack be recharged via the deep cycle and then used standalone? How long will it take to recharge the powerpack?

Depending on the answers I may want to go with the 20Ah...

I'd appreciate any feedback so that I know what to get when I make my next back up power purchases.

Thanks!
d

p.s. I was able to get the Duracell DR600PWR 18Ah powerpack delivered to my home for $120 (coupons helped!) and I found the Sears JumpStart Platinum Portable Power 22Ah 1150 model that has been mentioned several times on other threads for a reduced price of $80 (plus tax) but you'd need to pick it up from a Sears store near you AND the item would need to be in stock.
Last edited by sleep_quest on Thu Oct 23, 2014 11:53 pm, edited 2 times in total.

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Re: My back up power set up questions

Post by Pugsy » Mon Oct 06, 2014 6:22 pm

I can't help much but to have any sort of idea how long your idea might work people will need to know what pressure you are using....the higher the pressure the greater the power consumption.
People get longer life out of battery when they use 5 or 6 cm pressure than someone who uses 15 or 16 with the exact same machine and setup.

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Re: My back up power set up questions

Post by sleep_quest » Mon Oct 06, 2014 6:36 pm

Good point, Pugsy. I've edited to include my pressures.

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Re: My back up power set up questions

Post by Guest » Mon Oct 06, 2014 7:10 pm

sleep_quest wrote: Aside from hooking the CPAP up directly to the deep cycle battery, does it make sense to pigtail (is that the right word?) the Duracell powerpack via the built in jumper cables to the deep cycle battery for charging/longer CPAP run time in the event of a long term power outage?
I think what you are saying is to connect the jump starter cables exaclty like you would to jump start a car? If so, meaning negative to negative and positive to positive that is a parallel connection but that doesn't matter if you can't remember it that way just remember how to jump a car and connect it that way.

YES, it will work and will extend the useful time depending on the size of the deep cycle battery. But YES this a an excellent plug n play option and all you really need. To charge the jumper you could connect it just that way (negative to negative and positive to positive) to your car when your car is running to charge the jumper. You would need other jumper cables to charge the deep cycle that way when there is no AC power.
sleep_quest wrote:I currently have a new model Duracell DR600PWR 18Ah powerpack bedside...
I think they also make this Duracell with a 22ah battery model. I (personally) would have no problems keeping this and/or the deep cycle at my bedside. Unless you are smoking or lighting candles etc. in your bedroom and even then prob wouldn't cause a problem.
sleep_quest wrote:then I can charge the powerpack using the deep cycle battery and use each separately as well as pigtail the two together for a longer term electrical source. Does this make sense and will it work as I describe?
It makes sense tho I would use them together when possible rather than one to charge the other - that is unless you need to be portable form some reason - like evacuation and can't carry everything tho I think I would still try to take both.
sleep_quest wrote: found the Sears JumpStart Platinum Portable Power 22Ah 1150 model
Another good choice. I would not bother with the 12ah battery you mentioned as it wouldn't give you the time you mentioned...
sleep_quest wrote:My ultimate set up would last more than a few days (I live in earthquake country), be easy to set up (keep those "caution! make sure you have your positive/negative cables in the right place lest you blow up your CPAP machine and who knows what else" warnings to a minimum), be safe indoors, and be cost efficient. Think plug and play...not a lot to ask, right?
If the pocket permits I would buy another jump starter (and deep cycle) about 6 months or a year later. Reason being the batteries will not last forever and need to be replaced. IF you buy everything at once they will fail all at once or nearly so. Plus you will want to have at least two so one can be charging while the other can be used.

Whatever you do - be certain to try everything out BEFORE you need to use it. Try it out at home on a weekend or a time when you don't have to run off the next day.

Don't forget to pick up a battery tester and/or voltmeter also.

I won't go into the StarkPower batteries cuz I will not pay that kind of money.

I won't speculate on these...
sleep_quest wrote: I'm only powering my PRS1 560 without the humidifier (Pressure: APAP 9.0 min/15 max) how many hours can I expect from the different configurations of this setup assuming the source is fully charged (sorry, math is not my strong suit)?
as there are too many variables and will change as the batteries age and wear. Use the battery tester or voltmeter you picked up.

And Finally, always be certain to charge your batteries when you get them and the great debate is whether to keep them plugged in or not. To which I say - how can you tell when the power will go out - stay prepared and stay charged up.

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Re: My back up power set up questions

Post by eleong2 » Mon Oct 06, 2014 8:03 pm

sleep_quest wrote:Good point, Pugsy. I've edited to include my pressures.
Lithium batteries no matter what formulation has the inherent danger of catastrophic failure. Most lithium battery suppliers recommend that you don't leave them charging unattended. The battery chargers themselves need to shutoff automatically so as not to overcharge the battery pack. If all of the precautions are taken they are relatively safe. The lithium battery packs also have protective circuitry built in to limit over current, over discharge conditions. This is one of the reasons cost is high, for a battery pack that supplies 10Ah of power can be quite expensive and then you need to also buy a special charger that fits the need. If you take apart a laptop battery pack you'll see. Another thing don't get them wet, electric cars have known to catch fire when caught in flood waters.

I put together a battery pack for my PR System One (460) using a 12V. 22Ah sealed AGM lead acid battery. I get about 3 evenings (with the humidifier off) and I am around 50% charge. But you definitely have two good nights of power. Those portable power packs are also great for the task when your using the 12 V output. No matter what anything with lead in it will be heavy.

Cost wise the sealed lead acid batteries has a definite power cost advantage over an equivalent Lithium battery, but not the weight.

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Re: My back up power set up questions

Post by raftergirl » Mon Oct 06, 2014 8:08 pm

My batteries are AGM not SLA, so they are a little safer (can be tipped over). At your pressures you could probably get 3 nights, maybe 4 from one 12V20A battery without the humidifier. Two of them would get you at least a week without the humidifier in an emergency situation. These batteries aren't very big 7 X 3 X 6 inches give or take. They weigh about 12-13 lb. Mine cost $60 each, so not very expensive. I can't speak to linking them together, as I'm not very savvy about that kind of thing. For my use, I needed to be sure I'd have power for 8 nights at my pressures (15-17). Like I said in my other post, finding a power source that's small, light, reliable, and inexpensive in one package is tricky. The LiPO4 batteries are more money than the AGM, but less than the Li Ion, and definitely lighter in weight. If they can tolerate being drained lower than the AGM, and have a longer lifetime of recharges, then maybe they will pay for themselves in the long run. Right now I've invested in the AGM for rafting, but I may look into them for times when I must have a smaller & lighter option.

At 15-17, without a humidifier, in a tent, with temps. of 32-40, I got 2 mights per battery with around 1/3 charge left. One battery gave me three nights. I was using a very simple battery tester, so I can't say for certain how much charge was left after 2-3 nights. Battery tester ...... Green, yellow, red lights. All three = full charge. All of my batteries showed red & yellow after 2-3 nights.

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Re: My back up power set up questions

Post by eleong2 » Mon Oct 06, 2014 8:32 pm

raftergirl wrote:My batteries are AGM not SLA, so they are a little safer (can be tipped over). At your pressures you could probably get 3 nights, maybe 4 from one 12V20A battery without the humidifier. Two of them would get you at least a week without the humidifier in an emergency situation. These batteries aren't very big 7 X 3 X 6 inches give or take. They weigh about 12-13 lb. Mine cost $60 each, so not very expensive. I can't speak to linking them together, as I'm not very savvy about that kind of thing. For my use, I needed to be sure I'd have power for 8 nights at my pressures (15-17). Like I said in my other post, finding a power source that's small, light, reliable, and inexpensive in one package is tricky. The LiPO4 batteries are more money than the AGM, but less than the Li Ion, and definitely lighter in weight. If they can tolerate being drained lower than the AGM, and have a longer lifetime of recharges, then maybe they will pay for themselves in the long run. Right now I've invested in the AGM for rafting, but I may look into them for times when I must have a smaller & lighter option.

At 15-17, without a humidifier, in a tent, with temps. of 32-40, I got 2 mights per battery with around 1/3 charge left. One battery gave me three nights. I was using a very simple battery tester, so I can't say for certain how much charge was left after 2-3 nights. Battery tester ...... Green, yellow, red lights. All three = full charge. All of my batteries showed red & yellow after 2-3 nights.
rafter girl,
You can put those two AGM batteries in "parallel" , tie the plus sides together and the negative together you will then have a 40Ah battery pack. Tie them in parallel you add the current capacity.

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Re: My back up power set up questions

Post by CapnLoki » Mon Oct 06, 2014 8:54 pm

You ask a lot of questions!

sleep_quest wrote: I'll admit my ignorance right up front...I've been following the various backup power posts with the hope of finding just the right set up that would work for me at home however, I get glassy eyed with some of the technical jargon. To put it plainly, I get that a higher amp hour back up source will last longer than lower amp hour ones. I also get that there are many options with varying amounts of effort/skill needed to build them: back up unit from CPAP.com, deep cycle marine battery, lithium ion battery, car jump starter, UPS etc. TOO Many Options have my head spinning and I don't want to solder, weld, wire, or otherwise construct my back up power solution. My ultimate set up would last more than a few days (I live in earthquake country), be easy to set up (keep those "caution! make sure you have your positive/negative cables in the right place lest you blow up your CPAP machine and who knows what else" warnings to a minimum), be safe indoors, and be cost efficient. Think plug and play...not a lot to ask, right?

I currently have a new model Duracell DR600PWR 18Ah powerpack
The Duracell (or the similar Sears) are reasonable alternatives to the cobble together approaches we often discuss. However, they have small batteries, cheap chargers, and low quality inverters. You're paying a premium for the assembled product, but taking a risk that a minor failure will render it all useless. With that in mind, it still a reasonable choice if you understand the compromise.
sleep_quest wrote: bedside and I've purchased the Shielded DC Cord for PR System One 60 Series Machines and the Respironics, 12volt DC Battery Adapter Cable with Battery Clips so that I have the option of hooking up to a deep cycle battery in the future. Aside from hooking the CPAP up directly to the deep cycle battery, does it make sense to pigtail (is that the right word?) the Duracell powerpack via the built in jumper cables to the deep cycle battery for charging/longer CPAP run time in the event of a long term power outage? My thought is this solution will give me several different options if it will work. I'll have the powerpack to use directly with my CPAP for short term use (it has a single DC and 2 AC outlets plus 2 USB ports which can also be used with other electronic devices), and then I can charge the powerpack using the deep cycle battery and use each separately as well as pigtail the two together for a longer term electrical source. Does this make sense and will it work as I describe?
Your system might work but there's a few problems. How do you charge the external Deep Cycle? I would use a "Battery Tender" brand charger, but if you have that, what does the Duracell give you? And the dangerous part of the system is connecting everything with the jumper cables and alligator clips. Short them together and you can burn the house down! If you want to use the Duracell get the Series 60 "Cigarette Lighter" cable; if you're willing to properly wire a naked battery, why have the Duracell?
sleep_quest wrote:
If it works what about the safety of having the Lithium Iron Phosphate battery stored next to my bed vs. a lead acid battery and the issue with gasses emanating/acid spilling from it
Lithium batteries are generally safe, though you want to make sure you have the proper charger for chemistry of the battery. With traditional flooded batteries you can tip them over so most people go with some form of leakproof battery. The "hydrogen gas" risk is actually minimal, especially if you use small chargers - batteries explode from severe over charging, not the little trickle chargers powered by wall warts. AGM batteries are still lead acid, but sealed in such a way that nothing escapes (they do a relief valve so they won't explode) but I would have no problem having one in the bedroom. Think of of the elderly folks (my father included) who are charging their electric scooters or nerds (like me) charging UPS power supples. They all have the same small AGM battery your Duracell has.
sleep_quest wrote:

If I buy a 12Ah battery and I'm only powering my PRS1 560 without the humidifier (Pressure: APAP 9.0 min/15 max) how many hours can I expect from the different configurations of this setup assuming the source is fully charged (sorry, math is not my strong suit)?
CPAP connected to powerpack standalone via AC?
CPAP connected to powerpack standalone via DC?
CPAP connected via 12volt DC Battery Adapter Cable with Battery Clips to lead acid deep cycle battery
CPAP connected via 12volt DC Battery Adapter Cable with Battery Clips to LiFePO4
CPAP connected to powerpack via DC and powerpack is pigtailed to lead acid deep cycle battery
CPAP connected to powerpack via DC and powerpack is pigtailed to LiFePO4
How many times can the powerpack be recharged via the deep cycle and then used standalone? How long will it take to recharge the powerpack?
It comes down to this: running through the AC inverter will be about 60% efficient. 12 AmpHours is the same whether its LiFePO4 or AGM, although the AGM may suffer more from running down to zero. My guess is a 560 at 9.0 (that's actually what I have) is about 4 AmpHours/night at sea level. That should give you two nights with enough left over that you're not damaging the battery. The LiFePO4 is so expensive you probably don't want to oversize it, but the AGM is about a third or a quarter of the cost so you can double the size and have a generous safety margin.

I don't see any value in combining the powerpack with a battery. BTW, the battery inside the Duracell is a generic AGM battery. Perhaps they left room for a larger or a second battery?

It wasn't clear to me the power pack can be charged from an external battery. I think it can be charged from a generator or a car while they are running and thus putting out 14 Volts or more for charging. One 12V battery can only transfer a tiny charge to another 12V battery.
sleep_quest wrote: Depending on the answers I may want to go with the 20Ah...
In AGM, I would not go any smaller unless you have a weight issue. If you don't have a generator and long term outage is possible, I'd consider a larger battery like a 80 AH AGM that could run for a week or more and charge your cell phones. The wiring really isn't that hard.

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Re: My back up power set up questions

Post by archangle » Mon Oct 06, 2014 9:01 pm

If you don't need to move it around, a cheap deep cycle lead-acid battery is the best solution, no if's, and's, or but's. You don't even need to pay extra for sealed AGM or gel cell batteries if you can set it somewhere you won't turn it over. Put it in a battery box, and get the right charger, and you're done.

Check the water level every few months, plan on replacing the battery every 5 years or so. The lead acid will still be far cheaper than any equivalent lithium battery solution.

Lithium batteries are finicky about charging, and have a tendency to just die suddenly without any warning. There's also the question of fire. Even Sony and Boeing have had problems with lithium battery fires.

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Re: My back up power set up questions

Post by Guest » Mon Oct 06, 2014 9:31 pm

CapnLoki wrote:but if you have that, what does the Duracell give you?
The Duracell provides a plug in point for the cpap plus other features that are handy when the lights go out.
CapnLoki wrote:If you want to use the Duracell get the Series 60 "Cigarette Lighter" cable; if you're willing to properly wire a naked battery, why have the Duracell?
Did you not read what was posted?
sleep_quest wrote:TOO Many Options have my head spinning and I don't want to solder, weld, wire, or otherwise construct my back up power solution. ... Think plug and play...not a lot to ask, right?
sleep_quest wrote:I've purchased the Shielded DC Cord for PR System One 60 Series Machines
CapnLoki wrote:If you want to use the Duracell get the Series 60 "Cigarette Lighter" cable; if you're willing to properly wire a naked battery, why have the Duracell?
I can do it BUT I understand not everyone wants to wire or assemble their back up battery setup for their cpap. I think the poster is doing fine and should continue to post any more questions or stumbling blocks.
CapnLoki wrote:And the dangerous part of the system is connecting everything with the jumper cables and alligator clips. Short them together and you can burn the house down!
Stop it already STOP. The cables that come with the Durcell are no danger STOP to burning the house down. You are simply an alarmist. Stop it already.

Did you not read this....
sleep_quest wrote:I've purchased the Shielded DC Cord for PR System One 60 Series Machines
OR this...
sleep_quest wrote:TOO Many Options have my head spinning and I don't want to solder, weld, wire, or otherwise construct my back up power solution. ... Think plug and play...not a lot to ask, right?
I am convinced you didn't read the post.

Keep in mind not everyone needs or wants to assemble or wire up batteries nor do they need your setup.
sleep_quest wrote:Think plug and play...not a lot to ask, right?

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Re: My back up power set up questions

Post by sleep_quest » Tue Oct 07, 2014 1:12 am

Thank you all for your input. I do have some follow up questions:

As a general rule, is there a difference in the amount of power an item uses when it's connected via AC vs. DC? I thought I'd read that a DC connection would provide more therapy time so that's why I bought the DC power cord for my PRS1 560 to use with my powerpack.

Based on what I've read, it sounds like the type of deep cycle batteries I should be looking for are AGMs [aren't AGMs a subset of SLAs (sealed lead acid) batteries?] so that I don't need to worry about leaking gas or spills, correct? Someone said they got their battery at Costco and since they come in different Amp Hour levels what is a good size for my needs? I will take your advice, Guest, and buy two but at different times so I can maximize my back up situation. I only really need one at a time since I do have my powerpack which, in theory, should give me at least 8 hours of therapy on it's own. I will definitely test out this system prior to needing it.

This was supposed to be my generic "Oh the power's out, plug the CPAP unit into the back up power supply and go back to sleep solution". I didn't actually think about needing this back up system to be portable as in "ok we need to evacuate our home quickly" so maybe that was a little short sighted on my part. I do live within a few miles of the San Andreas fault and darn it if this new diagnosis hasn't complicated my evacuation planning. I guess I'll need to think about this a bit but thanks, Guest, for the dose of reality. If I can't remain in my home after an emergency then I'll need to pack my back up power supply and get it to wherever we end up. Maybe I'll need a dedicated dolly with the batteries all strapped to it ready to move at a moments notice. This just turned out to be a much bigger project than I anticipated...gulp.

More to come...
thanks,
d
Last edited by sleep_quest on Tue Oct 07, 2014 7:23 pm, edited 1 time in total.

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Re: My back up power set up questions

Post by archangle » Tue Oct 07, 2014 5:06 am

sleep_quest wrote:Thank you all for your input. I do have some follow up questions:

As a general rule, is there a difference in the amount of power an item uses when it's connected via AC vs. DC? I thought I'd read that a DC connection would provide more therapy time so that's why I bought the DC power cord for my PRS1 560 to use with my powerpack.

Based on what I've read, it sounds like the type of deep cycle batteries I should be looking for are AGMs [aren't AGMs a subset of SLAs (sealed lead acid) batteries?] so that I don't need to worry about leaking gas or spills, correct? Someone said they got their battery at Costco and since they come in different Amp Hour levels what is a good size for my needs? I will take your advice, Guest, and buy two but a different times so I can maximize my back up situation. I only really need one at a time since I do have my powerpack which, in theory, should give me at least 8 hours of therapy on it's own. I will definitely test out this system prior to needing it.
PRS1 and ResMed run off of DC power. The power brick converts AC to DC.

You can use a battery with an inverter to generate AC, and then plug the power converter into that. You waste some energy converting to AC and a little more converting back to DC.

Your PRS1 machine will run directly off of 12V, which makes more efficient use of the energy in your battery. You need an optional cable to connect to the battery.

ResMed S9 machines need either AC, or the overpriced ResMed DC-DC converter. The DC-DC converter is probably more efficient than using and inverter plus the power brick, but not as efficient as a direct DC connection like you can do with the PRS1.

AGM's are a type of SLA (Sealed Lead Acid) or VRLA Valve Regulated Lead Acid. Quite a few people misuse the terms Gel cell and AGM.

In practice, a single car battery sized lead acid battery does not generate enough gas to worry about. Gas can accumulate inside the battery case itself, so don't make sparks or flames when you open the covers on the cells. Unless you put the battery in an airtight case, you simply can't generate hydrogen fast enough for it to accumulate.

Look at it this way. Lead acid batteries make hydrogen by "boiling" (really electrolyzing) the water in the battery and turning it into hydrogen and oxygen. If you were overcharging the battery so badly that it used a pint of water (16 oz), a day, it would only produce 2 oz of hydrogen per day. That two ounces would have a full day to dissipate. Hydrogen dissipates very rapidly because it's such a small molecule.

It would be really difficult to put enough current into a lead acid battery to use up a full pint of water per day, so the real rate of hydrogen production would be lower. Have you ever had to add water every few days to a car battery? If you had a battery that you had to add a pint to every month, that would be something like 0.06 ounces of hydrogen per day.

BTW, if you overcharge a sealed lead acid battery fast enough, it will also generate hydrogen gas. The "valve" part of VRLA is an overpressure relief valve. Sealed lead acid batteries will recombine a small amount of hydrogen back into water every day, but the capacity to do this is limited.

Hydrogen gas IS a problem if you have something like a charging station for forklifts, or a large solar power solar system battery, bank or a commercial battery backup for a computer room. Also, don't make sparks if you have the caps off the top of the battery.

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Re: My back up power set up questions

Post by Guest » Tue Oct 07, 2014 5:37 am

Guest wrote:
sleep_quest wrote: Aside from hooking the CPAP up directly to the deep cycle battery, does it make sense to pigtail (is that the right word?) the Duracell powerpack via the built in jumper cables to the deep cycle battery for charging/longer CPAP run time in the event of a long term power outage?
I think what you are saying is to connect the jump starter cables exaclty like you would to jump start a car? If so, meaning negative to negative and positive to positive that is a parallel connection but that doesn't matter if you can't remember it that way just remember how to jump a car and connect it that way.

YES, it will work and will extend the useful time depending on the size of the deep cycle battery. But YES this a an excellent plug n play option and all you really need. To charge the jumper you could connect it just that way (negative to negative and positive to positive) to your car when your car is running to charge the jumper. You would need other jumper cables to charge the deep cycle that way when there is no AC power.
sleep_quest wrote:I currently have a new model Duracell DR600PWR 18Ah powerpack bedside...
I think they also make this Duracell with a 22ah battery model. I (personally) would have no problems keeping this and/or the deep cycle at my bedside. Unless you are smoking or lighting candles etc. in your bedroom and even then prob wouldn't cause a problem.


I would not attempt to charge a Jump Starter using the Jump Starter Cables. First, the Jump starter cables are not designed to work that way, they are set up to provide a large immediate amp output to Start Cars, not charge its own internal Batteries. I would suspect that the electronics actually are set up to prevent rapid charging in this manner. On mine, a special switch must be enabled to use the Jump Start cables. If you are not comfortable with wiring from the Deep cycle to the jump starter charge port, simply use the supplied car charger that plugs into the cigarette Lighter, and charge off of your car battery. This would be a much safer option.

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AlabamaAl
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Re: My back up power set up questions

Post by AlabamaAl » Tue Oct 07, 2014 5:42 am

Guest wrote:
sleep_quest wrote: Aside from hooking the CPAP up directly to the deep cycle battery, does it make sense to pigtail (is that the right word?) the Duracell powerpack via the built in jumper cables to the deep cycle battery for charging/longer CPAP run time in the event of a long term power outage?
I think what you are saying is to connect the jump starter cables exaclty like you would to jump start a car? If so, meaning negative to negative and positive to positive that is a parallel connection but that doesn't matter if you can't remember it that way just remember how to jump a car and connect it that way.

YES, it will work and will extend the useful time depending on the size of the deep cycle battery. But YES this a an excellent plug n play option and all you really need. To charge the jumper you could connect it just that way (negative to negative and positive to positive) to your car when your car is running to charge the jumper. You would need other jumper cables to charge the deep cycle that way when there is no AC power.
sleep_quest wrote:I currently have a new model Duracell DR600PWR 18Ah powerpack bedside...
I think they also make this Duracell with a 22ah battery model. I (personally) would have no problems keeping this and/or the deep cycle at my bedside. Unless you are smoking or lighting candles etc. in your bedroom and even then prob wouldn't cause a problem.


I would not attempt to charge a Jump Starter using the Jump Starter Cables. First, the Jump starter cables are not designed to work that way, they are set up to provide a large immediate amp output to Start Cars, not charge its own internal Batteries. I would suspect that the electronics actually are set up to prevent rapid charging in this manner. On mine, a special switch must be enabled to use the Jump Start cables. If you are not comfortable with wiring from the Deep cycle to the jump starter charge port, simply use the supplied car charger that plugs into the cigarette Lighter, and charge off of your car battery. This would be a much safer option.

I have to apologize, the above reply was mine, but for some reason I was not logged in.

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Re: My back up power set up questions

Post by Guest » Tue Oct 07, 2014 6:50 am

Sleep_quest, I think AA answered most of your questions so I would like to address the 2nd AA who appears to have contradicted himself.
AlabamaAl wrote:I would not attempt to charge a Jump Starter using the Jump Starter Cables. First, the Jump starter cables are not designed to work that way, they are set up to provide a large immediate amp output to Start Cars, not charge its own internal Batteries. I would suspect that the electronics actually are set up to prevent rapid charging in this manner.
The jump starter will provide a far larger current when jumping a car than it would to (connected the very same way) charge (with car already running) from the car to the jumper. So they are more than capable of handling any charge current.
AlabamaAl wrote:On mine, a special switch must be enabled to use the Jump Start cables.
On mine that switch connects the post of the car directly to the like post on the jumper, no electronics involved. I have another where there is no switch involved - the cables are connected directly to the battery. For both that is the quickest way to re-charge the jumper. Using the provided wall wart to charge could take days because it is a smaller (trickle) current.
AlabamaAl wrote: If you are not comfortable with wiring from the Deep cycle to the jump starter charge port, simply use the supplied car charger that plugs into the cigarette Lighter, and charge off of your car battery. This would be a much safer option.
While that is another option it will not charge the battery as quickly and only serves to confuse a novice. That cable is used by tow truck operators to keep their jumper fully charged and ready-to-go. Using either method the engine needs to be running.

Normally when the power is out you are not out driving around to make using that cable feasible and looking to conserve any fuel in your car as the gas stations can't pump until the power is restored. And if they do have power there will be long lines - so a reminder here - always fill up the cars before any storm hits. In an earthquake region that is not possible; by habit you may not want to go below half a tank.