How do I connect alligator clips to an AGM battery for CPAP?

CapnLoki wrote: ↑

Sun Jul 22, 2018 8:37 pm

mileena wrote: ↑

Sun Jul 22, 2018 8:31 pm

Thank you. This is really getting me excited to be ordering all of this and see it works! Would this adpater cord that palerider mentioned on the first page replace the last two apater cords I showed above:

Yes - that cable combines the ring and the socket, but it doesn't have the "quick-connector" that allows you to plug in the BatteryTender charger. My solution has more parts but allows you to switch between the charger and the pump without using alligator clips.

Ok, I see now! So you don't have to unbolt the eyelets from the AGM battery when you charge it!

mileena wrote: ↑

Sun Jul 22, 2018 8:27 pm

CapnLoki wrote: ↑

Sun Jul 22, 2018 8:20 pm

mileena wrote: ↑

Sun Jul 22, 2018 6:31 pm

I love that box! Do you need to change the fuses so the amps are correct for your CPAP, or do the same fuses work for both the CPAP and marine stuff?

The box is neat - I found it a bit overkill but many folks like it. Fuses are not sized for the device, they are sized for the wiring. Its like in a house where an outlet will have a 15 Amp breaker regardless of what is plugged into it. Matching the breaker, the wires, and the outlet to the same capability is the responsibility of the electrician.

The BatteryTender cable has a fuse - 10 amps I think. And the Respironics cable has an 8 amp fuse in its tip.

All these fuses are nice but its actually fairly unlikely that there will be a problem because you'll be handling the wires and will notice a break that would be a problem (unlike on a car or boat where some hidden wire is corroded, etc.) The real risk is the simple situation where someone puts a metal lunch box on the battery, shorting the terminals! Fuses won't protect against that which is why I like a box.

Got it! As long as there are fuses already that will work, I am set then.

I am old enough to remember the days of the metal lunch boxes, along with the thermos, when I was a kid:


heathcliff.jpg

You are young I remember when you had paper bags and a water fountain. You are a Pup! Jim

I remember when my thermos broke.
Ate my sandwich--did not particularly miss the Campbell's garbage vegetable soup.

chunkyfrog wrote: ↑

Sun Jul 22, 2018 10:03 pm

I remember when my thermos broke.
Ate my sandwich--did not particularly miss the Campbell's garbage vegetable soup.

Now! Now! Be nice, thanks to Mr. Campbell I passed 1 ST Grade! Jim

mileena wrote: ↑

Sun Jul 22, 2018 6:03 pm

I was advised that the amps for a battery charger need to be 20% of the AH for an AGM battery in this post linked and also quoted below:

viewtopic/t171447/Can-anyone-recommend- ... 5#p1249441

AGM's use the same chargers as car batteries, so there are a lot of inexpensive options. I like the BatteryTender trickle chargers because they are very gentle and reliable, but the largest is only 5 Amps. You want a charger that puts out at least a quarter of the size of battery - i.e. a 40 Amp-hour battery would like about 10 Amps when charging. The 35 AH batteries are a luggable 25 pounds, I like the 50% to 85% charging protocol, but it can be pushed to 20% to 90% at the cost of lifetime and charge time. This might mean something like 3 hours charging once a week, total life reduced from about 1000 cycles to 500 -still not bad for a $65 battery. Also, you can get a second battery and rotate as needed.

So if my AGM is 35 AH, I would need a charger that is 7 amps. That is why I was looking at the 10 amp charger above in my second post. But if you say 5 amps are good, then so be it!

So I think I mis-spoke on this - I should have said "for fastest charging you need about 20%" because the battery won't accept more. A smaller charger will take longer, a bigger charger won't save much time and runs a risk of overcharging (if its low quality), so its a bit of a balancing act to find the perfect match. When I said "at least 20%" I was thinking you needed to minimize the charge time; but if you're looking for a smaller, less conspicuous package then the compact 5 amp BatteryTender may be the best, even though it may take 15 minutes longer to charge. If you keep the battery in a "middle" state of charge, it will take about an hour for each night of use. Also, as I've mentioned before, you may want two batteries, and they don't have to be the same size.

mileena wrote: ↑

Sun Jul 22, 2018 8:42 pm

Ok, I see now! So you don't have to unbolt the eyelets from the AGM battery when you charge it!

Yes, exactly! And you can tape up the terminals so they can't be shorted out.

You asked about the marine battery box. There are other boxes available for purchase besides the one I own. As you can see it's 3 times the size of my cpap. Probably overkill, but I also use it to run my boat trolling motor. I have a large battery which works for 9 nights of camping and takes the battery down to 50% charge. I don't have to charge the battery while I'm camping. I charge the battery at home with the typical battery charger that clips on the the battery posts.

The box has wires inside that bolt onto the battery.

The box has the 12v socket built in so all you have to do is plug in your xpap cord. It also has a USB socket and the terminals for a trolling motor. The box has two circuit breakers, one is 30 amp for a trolling motor and the other is 10 amp for the accessory sockets. The reason I bought this box is that it has circuit breakers for both the trolling motor and accessories. It also has LED lights that tell approximately how much of a charge your battery has.

If you look at your xpap cord the end will unscrew and there's already a fuse inside to protect your xpap and cord from shorts.

This is where the fuse is hidden. A person should have some extras for backup. Mine has an 8amp slow blow fuse. Not sure if all cords are the same.

Goofproof wrote: ↑

Sun Jul 22, 2018 9:58 pm

You are young I remember when you had paper bags and a water fountain. You are a Pup! Jim

Well, haha, I appreciate the compliment Jim! Too bad I don't feel that young! We still used paper bags sometimes too. At least things were better in your day compared to nowadays. I'm still partial to the old school methods.

CapnLoki wrote: ↑

Mon Jul 23, 2018 5:25 am

mileena wrote: ↑

Sun Jul 22, 2018 6:03 pm

I was advised that the amps for a battery charger need to be 20% of the AH for an AGM battery in this post linked and also quoted below:

viewtopic/t171447/Can-anyone-recommend- ... 5#p1249441

AGM's use the same chargers as car batteries, so there are a lot of inexpensive options. I like the BatteryTender trickle chargers because they are very gentle and reliable, but the largest is only 5 Amps. You want a charger that puts out at least a quarter of the size of battery - i.e. a 40 Amp-hour battery would like about 10 Amps when charging. The 35 AH batteries are a luggable 25 pounds, I like the 50% to 85% charging protocol, but it can be pushed to 20% to 90% at the cost of lifetime and charge time. This might mean something like 3 hours charging once a week, total life reduced from about 1000 cycles to 500 -still not bad for a $65 battery. Also, you can get a second battery and rotate as needed.

So if my AGM is 35 AH, I would need a charger that is 7 amps. That is why I was looking at the 10 amp charger above in my second post. But if you say 5 amps are good, then so be it!

So I think I mis-spoke on this - I should have said "for fastest charging you need about 20%" because the battery won't accept more. A smaller charger will take longer, a bigger charger won't save much time and runs a risk of overcharging (if its low quality), so its a bit of a balancing act to find the perfect match. When I said "at least 20%" I was thinking you needed to minimize the charge time; but if you're looking for a smaller, less conspicuous package then the compact 5 amp BatteryTender may be the best, even though it may take 15 minutes longer to charge. If you keep the battery in a "middle" state of charge, it will take about an hour for each night of use. Also, as I've mentioned before, you may want two batteries, and they don't have to be the same size.

Ok, thank you for the clarification. I used to have one of those big professional mechanics 50/10/2 chargers by Schumacher. It was only like $70 at BJ's Wholesale Club back in the late 90's. It even had wheels and a handle so you could move it around in a garage. But that would be overkill for a CPAP machine. I will try to look at the size of that BatteryTender charger and the one I posted and see how much I can afford. Thank you.

CapnLoki wrote: ↑

Mon Jul 23, 2018 5:28 am

mileena wrote: ↑

Sun Jul 22, 2018 8:42 pm

Ok, I see now! So you don't have to unbolt the eyelets from the AGM battery when you charge it!

Yes, exactly! And you can tape up the terminals so they can't be shorted out.

Ok, well that is a lot cheaper than buying a battery box. I might do that instead.

Rob K wrote: ↑

Mon Jul 23, 2018 5:47 pm

You asked about the marine battery box. There are other boxes available for purchase besides the one I own. As you can see it's 3 times the size of my cpap. Probably overkill, but I also use it to run my boat trolling motor. I have a large battery which works for 9 nights of camping and takes the battery down to 50% charge. I don't have to charge the battery while I'm camping. I charge the battery at home with the typical battery charger that clips on the the battery posts.

The box has wires inside that bolt onto the battery.

The box has the 12v socket built in so all you have to do is plug in your xpap cord. It also has a USB socket and the terminals for a trolling motor. The box has two circuit breakers, one is 30 amp for a trolling motor and the other is 10 amp for the accessory sockets. The reason I bought this box is that it has circuit breakers for both the trolling motor and accessories. It also has LED lights that tell approximately how much of a charge your battery has.

If you look at your xpap cord the end will unscrew and there's already a fuse inside to protect your xpap and cord from shorts.

Thank you so much for posting those closeup pictures and also in your other post of the 12V plug. We'll see how much everything costs in the end, but it would be neat to have something similar to what you have, even though as you said, it might be overkill. I do especially like the idea of having the dual USB outlets so you can also use it at night to charge a phone or whatever.

CapnLoki wrote: ↑

Sun Jul 22, 2018 8:20 pm

mileena wrote: ↑

Sun Jul 22, 2018 6:31 pm

I love that box! Do you need to change the fuses so the amps are correct for your CPAP, or do the same fuses work for both the CPAP and marine stuff?

The box is neat - I found it a bit overkill but many folks like it. Fuses are not sized for the device, they are sized for the wiring. Its like in a house where an outlet will have a 15 Amp breaker regardless of what is plugged into it. Matching the breaker, the wires, and the outlet to the same capability is the responsibility of the electrician.

The BatteryTender cable has a fuse - 10 amps I think. And the Respironics cable has an 8 amp fuse in its tip.

All these fuses are nice but its actually fairly unlikely that there will be a problem because you'll be handling the wires and will notice a break that would be a problem (unlike on a car or boat where some hidden wire is corroded, etc.) The real risk is the simple situation where someone puts a metal lunch box on the battery, shorting the terminals! Fuses won't protect against that which is why I like a box.

I've never used a battery for my cpap, but I do use a marine battery to run my photo lights at a few venues that like to charge $75 or more for 1-3 days use of a power outlet. It has to travel, so I bought a two part rolling tool box. The bottom sections holds the battery perfectly. I drilled some some holes in it. The upper section holds the charger, the inverter, and and a power strip. I have a couple holes in the bottom, so the cables attached to the inverter go directly into the lower section. I have wood plank that is fitted for the top of the battery when not in use. Oh, and my dad added rounded, metal handles on the side. I have to take off the top section in order to lift the lower section into the car. That nicer handles really help. And I make sure hotels have an elevator or first floor room. I had to carry it up a set of stairs once to charge it overnight in the hotel room. Not fun.

I have a smaller jump start battery that I use for smaller things like laptops, charging, etc when I can't be near an outlet. This one has a DC outlet and an AC outlet, plus 4 usb outlets. And it has jump started my car a few times now. I don't know if it would run a cpap very long. It is much lighter, so probably not nearly as much power.

I haven't tried either since I normally run the humidifier on a higher setting.

mileena wrote: ↑

Thu Jul 26, 2018 12:43 am

Goofproof wrote: ↑

Sun Jul 22, 2018 9:58 pm

You are young I remember when you had paper bags and a water fountain. You are a Pup! Jim

Well, haha, I appreciate the compliment Jim! Too bad I don't feel that young! We still used paper bags sometimes too. At least things were better in your day compared to nowadays. I'm still partial to the old school methods.

If you were poor, you got the big Kroger Bags, or you had to go bagless. Personally we didn't get lunch period. We got Milk and Soda Crackers, if we could afford it, till Junior H.S.

The best part of Junior H.S., those women could cook, H.S., the best part I could take my car that I worked to support, and get a Burger. Better Times! Jim

Just to clarify the battery box I posted photos of has only one usb and only one 12v socket. It doesn't have dual usb sockets.

Rob K wrote: ↑

Thu Jul 26, 2018 5:19 pm

Just to clarify the battery box I posted photos of has only one usb and only one 12v socket. It doesn't have dual usb sockets.

A very belated thank you Rob. My bad!


I have another question for anybody to answer. I just bought the Freedom lithium portable battery for my CPAP for only $249, plus the 12V DC adapter cord with cigarette female socket for my DreamStation for $23.95. I need something that charges relatively quickly and is relatively portable since I will be using for about 30 days straight to power my CPAP, on the road, and charging it in public places, like the library or Starbucks.

But I don't know if I trust that to work that long. I want to buy an AGM battery with charger as well, to have as a backup. If my battery fails on the road, I am doomed. I had an accident a year when I didn't have my CPAP yet since I fell asleep at the wheel while travelling. I took out a street sign.

Here is the problem. The AGM battery generally have eyelet terminals, either vertical or horizontal, like in the pic below. These require a bolt.


However, all the battery chargers that have eyelet terminals as well are only 5 amp or below, like below:


But I need an 8-10 amp charger. I might only be near an electrical outlet for 4 or 5 hours per day or maybe every other day, so 5 amps is not good enough. But all the 8-10 amp charger use alligator clips, like below:


Can you connect alligator clips to an eyelet terminal on an AGM battery?? What if the AGM battery has horizontal terminals? How do you connect the alligator clips to these?

Also that Schumacher battery charger above is a lot cheaper than the Battery Tender one above!