Do I need expensive batteries?

[dig4gold]

2008 Eagle 299RLS 5er.I've had Interstate batteries in it since we bought it new in '09 and have not been disappointed. Last year we noticed they were not holding a charge worth a s*^#. So I need new batteries. But here's our situation; we always dry camp, no camp grounds with hookups for us, and I have to run a generator every night because I use a CPAP. So . . . do you think I need to get $100 + batteries or will the "Walmart brand" do the trick?

[bankr63]

I'd say 5-6 years on a battery that is probably getting pretty deep discharge cycles (you run the genny every day) is a good performance. Check the performance specs on the battery you are getting, does it have as much power reserve as your current battery? You don't want to take a step down.


IMO you get what you pay for in batteries. Expensive and cheap batteries will work well for the first year, but will the cheap one still be working at all in 5 years?


Personally I am probably due for a new battery as well this year, and will probably buy one of the AGM (Absorbent Glass Mat) RV batteries from my local Costco. The price is right, I like the low maintenance, and the power specs are pretty good.

[Rustysocket]

Look for the ratings on the battery in amp/hour. Pick the one with the biggest numbers not the biggest price tags. I've always used interstate batteries and fell that if I got five or six years out of them they have lived their life.

[TWP723]

I think there's only a couple different battery manufacturers anyway. Companies just slap their stickers on them and call them theirs. For example: Exide used to make the Sears Die Hard batteries.


Delphi
Exide
Johnson Controls

[Grumpy]

Interstate has always been a reliable brand, stick to what served you well.

[Subaru297]

Do you run the generator all night?

I would take this opportunity to upgrade to dual 6volt batteries.

[dig4gold]

I considered dual 6V, but would have to drastically modify the battery compartment so they would fit. I'm thinking that the batteries only have to work during daylight . . . as I am running the generator all night (10 - 12 hours)

[Mustang65]

Originally Posted by dig4gold

and I have to run a generator every night because I use a CPAP. So . . . do you think I need to get $100 + batteries or will the "Walmart brand" do the trick?

Generator just to run the CPAC machine???? Lets do the math....

If you get two DEDICATED standard RV/Marine Interstate 85Ah batteries (170Ah's of which 85Ah is useable - 50% rule), to run your CPAC machine.

So with 2 of the above batteries you have 1020 Wh (watt hours) that you can use for your CPAC machine [85Amp hours*12 volts=1020Watt hours]

I believe your CPAC machine's power source (transformer) is the same or close to mine. The transformer is a 12VDC transformer, check yours. Mine is rated at 5 amps at 12VDC, of which I have yet to hit 4 amps, with the CPAC humidifier on. If yours is not 12VDC, check with the mfr about a 12VDC CPAC adapter.

So, I will use 5 amps as the CPAC load, just in case yours may use 5 amps.

5 Amps * 12VDC = 60 watts.. 60 Watts *8 hours of sleep = 480Wh (Watt hours)..... not a bad number for a GOOD nights sleep.

If you look above, we calculated (2) 85Ah batteries will supply 1020Wh. So in theory, you could make it on one 85Ah battery (510Wh), but I think that would be cutting it a little close with no reserve.

A 100Ah battery would supply around 600 Watt hours, a little better.

I have no clue as to what you spend in a season on generator gas, but I believe going this route, will let you keep a few buck in your wallet.

You could wire in another small charge controller just for the CPAC battery(s) that will charge them when you run the generator during the day.

Or, install 250Watts of roof SOLAR wired directly to the CPAC batteries and forget about them (just regular maintenance, battery water). The batteries will be charged by noon or 2 the latest (clouds)

Oh yes, there is another benefit... no night time generator noise....

Just my thoughts,

Don

[bap]

You can also buy a rechargeable battery pack for your CPAP machine, some even have optional solar chargers. I have considered one for camping to open up dry camping options.

[dig4gold]

First of all . . . it's CPAP, and it doesn't have batteries. It's 120v. Unless my 5er has a power converter to go from 12V to 120V . . . I don't see where your math does me any good. Thanks for all your trouble and advice though.

[Ela1948]

Originally Posted by dig4gold

First of all . . . it's CPAP, and it doesn't have batteries. It's 120v. Unless my 5er has a power converter to go from 12V to 120V . . . I don't see where your math does me any good. Thanks for all your trouble and advice though.

I use a CPAP all the time and never run a generator at night. Some CPAP's have a 12 volt converter available. Even if you have a standard 120AC unit, there is no reason that you can't use a plug in inverter to power your CPAP off of your 12 volt batteries. If you disconnect the humidifier, they only draw about 80 watts.

[Jagiven]

Originally Posted by Ela1948

I use a CPAP all the time and never run a generator at night. Some CPAP's have a 12 volt converter available. Even if you have a standard 120AC unit, there is no reason that you can't use a plug in inverter to power your CPAP off of your 12 volt batteries. If you disconnect the humidifier, they only draw about 80 watts.

X2, my CPAP has a 12V option. I can run mine off a 12V deep cycle battery with no issues. I played with it, but not done it. I camp without mine. I know some people who do. If I recall correctly they can go a couple nights on a single battery charge on a dedicated battery.

But back to your original question. If you are running a genny all night, a cheap group 24 dual purpose battery would work for you.

[Mustang65]

Originally Posted by dig4gold

First of all . . . it's CPAP, and it doesn't have batteries. It's 120v. Unless my 5er has a power converter to go from 12V to 120V . . . I don't see where your math does me any good. Thanks for all your trouble and advice though.

Unless it is a new design that the 110VAC plug goes directly into the CPAC machine, it has an inline transformer that plugs into the CPAC machine. I have yet to see a CPAC machine that is wired directly to110VAC, but anything is possible.

What is the mfr/model of your machine.

Don