Lifeline amp hours

[SilverHouseDreams]

Originally Posted by gator.bigfoot

At least my lead acid batteries can be recycled and don't involve child labour. Let's me sleep at night for those with a conscience.
https://money.cnn.com/video/technolo...ney/index.html

Don't be so certain about your lead, it comes from somewhere...and a lot of lead mining (along with all minerals) occurs in developing countries where child labor is often in the mix. All mineral extraction is an ugly business, environmentally and health hazards regardless of who does the labor. I hope we can agree on that.

That said, the lithium batteries we are using do NOT have cobalt in them. They are also full recyclable, as they are the same cells used in many other applications (including some hybrids and EVs). We are using LFP, or lithium iron phosphate: https://en.wikipedia.org/wiki/Lithiu...sphate_battery

So please stop with the FUD (fear-uncertainty-doubt), unless its really necessary to reinforce your personal decisions?

[SuperTrouper]

Originally Posted by aspenmeadow

Hi all. My first post. Sorry for the stupidity of this question but I have a hard time with this stuff.

Ok here goes.

I understand that when two Lifeline GPL-4CT batteries are wired in series this creates 12v but the amp hours remain at 220. My question, with the understanding that you should only discharge a battery to 50%, is do I only have 110 amp hours at my disposal, or do I have the full 220? Thanks in advance for the clarification.

Hi Aspen,

To get back to your original questions and some comments. The two lifelines give you 110AH of usable power. I have had those batteries about 7 years. We use about 40 AH a day including 2 hours of video an evening. So 3 days or power. We don’t run the furnace overnight (as long as it’s not freezing). I added 400 watts of solar about 3 years ago and it’s suits our needs. We rarely run out of power. And conserve if we need to. Before I had a battery monitor I used to call 11.9 volts on a cheap plug in light type meter at the opposite end of the coach 50% “do not go lower” as measured it was about 2 tenths of a volt lower than at the terminals so 12.1vdc no load but no rest either. I’m thinking about lithium and it’s tempting but the lifelines and solar are covering well and the longevity with daily charging is great. I leave the power on in storage and leave the max fans on auto (one in and one out at 90 degrees) to dissipate heat mid day in the summer. So far so good! Enjoy your Airstream when you get it! Our family has had some real good times in it!. Brad

[aspenmeadow]

Thanks for the info Supertrouper it’s good to know how many amp hours people are getting a day and what they use. Info like that will help inform my decision.

[uncle_bob]

Originally Posted by aspenmeadow

Thanks for the info Supertrouper it’s good to know how many amp hours people are getting a day and what they use. Info like that will help inform my decision.

Hi

We run between about 60 and 90AH a day. In the deep shade of most campgrounds we get back about 10 to 20AH a day off of our solar setup. Usage is with zero run time on the inverter and thus no TV watching. With a 400AH stack, we can get to 5 days without any problems.

A fantastic fan pulls 1 to 4 amps. running one for 12 hours a day gets you to 24AH on low. My fridge pulls just over 1A running on propane. That gets you 24AH a day. The parasitic loads when the trailer is turned on are about an amp so that's another 24AH. There's a thread somewhere around here with more details ....

Bob

[SuperTrouper]

Yeah Bobs probably closer. We started measuring after we installed solar so probably closer to 60 AH a day because solar covers the other 20. I rarely see the battery monitor drop below -40 AH. We don’t run our fans much unless it’s sunny so the solar covers that and we always pick sunny campsites when we can.

[uncle_bob]

Hi

Well, if you get enough sun, you can get >=80AH from solar with a fairly modest set of panels. We do that well parked in front of the house. Our issue is that the campsites we like are off in the woods .... or it rains ... or it snows (yikes !!) ....

My conclusion ( = what drove me to lithium) was that I really could not count on the ~100 AH of stock batteries for a full two days, even with a little bit of solar. Toss in something like running the heat and it just was "to close" for me.

Bob

[Adventure.AS]

Originally Posted by OTRA15

Yes, bob, plenty of lithium threads, but the reason we never considered them is because you can't charge them in below-freezing weather, right? Seems like a real weak link in the chain for active trailer campers who may end up dry camping in their aluminum tent in cold weather.

Originally Posted by uncle_bob

Hi

Charging with the battery below freezing is cut out by the BMS. Discharge below some lower temperature is also cut out. We went with two batteries "indoors" and two in the battery compartment to minimize those issues. ...

No magic bullet, it's more things to consider when it's cold ....

Would a 12 volt silicone 'blanket heater' (similar to those used by AS for tanks that don't have furnace ducting) work to bring lithium batteries up to a warm enough temperature to allow charging? Although they would draw power to keep the batteries warm the converter/charger should be able to keep up and also add amps while plugged in. Perhaps it would even work when towing?

[uncle_bob]

Originally Posted by Adventure.AS

Would a 12 volt silicone 'blanket heater' (similar to those used by AS for tanks that don't have furnace ducting) work to bring lithium batteries up to a warm enough temperature to allow charging? Although they would draw power to keep the batteries warm the converter/charger should be able to keep up and also add amps while plugged in. Perhaps it would even work when towing?

Hi

Sure it (or something similar) would work. You would have the same basic limitations as a tank heater. It takes some power to get it going (maybe run it on 120V ...). Without insulation around the batteries, your "margin" might only rise by 10 degrees. You could get exotic and wrap them with a heat blanket. That sounds like a lot of work ....

The trick would be to not to too insane on the power levels. You can get hot spots doing this sort of thing. Melting the battery in the process ..... not a good outcome

Since the lithium's don't have the outgassing issues of a lead acid, bringing them into the normally heated space *is* an option. Then what do you do with the empty / wet / dirty / hard to get to battery box?

Bob

[VAtom]

Originally Posted by uncle_bob

Hi

The next layer to this onion is - how do you *know* you are at 50%?
Another answer is to put on a charge monitor that measures current in and out of the battery. That will give you a much more accurate idea of where you are. Without that, it's very hard to *know* how kind ( or nasty) you are treating your batteries.

Bob

Based upon other suggestions on the forum I bought and installed the BM-2 voltage monitor. It works well and has provided valuable feedback about SoC.

The app is free from the Play store, but the bluetooth set up is tricky. Basically, you don't connect thru the settings.

https://www.amazon.com/QUICKLYNKS-Ba...2&keywords=bm2

[stewartprice]

Here is the thing. . . you only get 220AH in series. So theoretically if you want your batts to last a long time you only discharge them to %50 or so. But that is a pain in the ass so why buy expensive AGMs when you can go to Costco, Sams's, Bulbs & Batteries, etc. etc. and buy a couple of 6v 115 AH golf cart battery for under $100 each? Run them down as much as you like until they give up and just get some new ones. You are still getting out way cheaper and they weigh about the same. The golf course people run them down all the time.

[guskmg]

On the lithiums: if you install them inside your trailer the cabin heat will always keep them warm enough. After all, you will be there to monitor the temperature for your comfort. You would not need to charge them if you were not there. Having said that, some people use an aquarium heating pad unerneath the batteries. The draw would be very low similar to an electric heated bed pad. If the batteries are under a bed the temperature will stay pretty stable. In the TX winters if my furnace ias set on 40 degrees I rarely set the battery temperature down to that temperature.
guskmg

[Road Geezer]

These are expensive batteries; I bought 3 31XTs for our AS. I really suggest you download and peruse the manual from their website. It's loaded with heavy duty technical jargon, but there's a lot of understandable info about their AGMs that can help prevent some expensive mistakes.


BTW, I talking about the 40+ page version, not the small owners manual that's included with the battery.

[uncle_bob]

Originally Posted by VAtom

Based upon other suggestions on the forum I bought and installed the BM-2 voltage monitor. It works well and has provided valuable feedback about SoC.

The app is free from the Play store, but the bluetooth set up is tricky. Basically, you don't connect thru the settings.

https://www.amazon.com/QUICKLYNKS-Ba...2&keywords=bm2

Hi

The problem with that device is that it's a voltage monitor, just like what comes stock with your AS. It has exactly the same limitations as the stock voltage monitor. It only makes a very rough guess at the state of the batteries. It is not anywhere close to a charge (current) based device in terms of accuracy.

Bob

[68 Overlander]

Originally Posted by uncle_bob

Hi

The problem with that device is that it's a voltage monitor, just like what comes stock with your AS. It has exactly the same limitations as the stock voltage monitor. It only makes a very rough guess at the state of the batteries. It is not anywhere close to a charge (current) based device in terms of accuracy.

Bob

That is correct, any voltage monitor is going to be dynamic and never accurate unless the voltage has stabilized for 8-10 hours. You will chase it. It can be useful for the starting battery in your TV however. With the Trimetric, you have a separate connection for that. A shunt is needed to monitor your house batteries in real time and that is where the trimetric really shines.

[uncle_bob]

Originally Posted by 68 Overlander

That is correct, any voltage monitor is going to be dynamic and never accurate unless the voltage has stabilized for 8-10 hours. You will chase it. ......

Hi

Actually it's worse than that. Battery voltages are temperature dependent. Based on watching the temperature readout on my battery box, they can vary a lot. Sit out in the hot summer sun and they get nice and toasty. Get a cold snap at nigh in the fall and they get quite cold. This stuff can throw your "magic voltages" (all of them) off by a half a volt. All of a sudden 12.1V is 12.6 or 11.6 ....

Sure, right now this morning the batteries are at 70F. Voltages would be right were you expect them to be. Over the last few weeks, there have been points where they were a *lot* hotter than that.

So why not just post a chart?

Well, various manufacturers mess with this and that to change the chemistry of the batteries they sell. What one does may not be what another one does. One changes a bit more cold. Another one changes a bit more at hot. Yet another reason to always replace batteries in pairs.

Bob

[SuperTrouper]

Hi Aspen,

Just back from yellowstone and grand teton with my wife and 14 year old son. We camped dry at Mammoth 4 nights and Lizard Creek 2 nights with 1 night at Grizzly in West yellowstone in between to empty and fill water tanks. So for some real world numbers:

Our system consists of (2) 7 year old lifeline GPL-4CT 6 volt batteries in series, IOTA DLS-45 3 stage charger/converter , Sure-Sine 300 Watt inverter, Blue Sky 3024iL Solar Charger with IPN Pro-Remote interface and (4) 100 watt solar panels all on a 2008 27FB. All solar parts and inverter purchased as package from AM Solar and installed by me. I ran #4 AWG cables from the roof to the charger.

Our power consumption consisted of evening (2) Maxx fan and hood exhaust fan use, interior LED lighting, continuous inverter power charging laptops and cell phones using 120V. We ran the furnace an hour each morning to pull the chill (40 degrees) out of the trailer. My son watched a movie each evening utilizing the inverter/TV combo 2-3 hours). We were gone during most of each day to see the wondrous sights allowing for recharging of the batteries. We had morning through midday sun coverage at Mammoth (we asked hosts for a sunny spot when we checked in) and midday (partial) sun at Lizard Creek. The lowest battery reading on the IPN Pro was 12.1 volt at -69 Amp Hours and 67% charge (theoretically we have 110 AH available). Most days we were recharged by evening except two days when we started the evening at -11AH because of nasty weather in mammoth or limited sun in Lizard creek. As an aside, we utilized paper plates for meals but my wife cooked each day using pots and pans and we utilized glass-plastic ware for drinks. We washed said items nightly in a tub and dumped the tub in the black tank. We showered using brief showers every two days and refilled the fresh water once for the 4 nights at Mammoth and ended up with 1/4 tank fresh remaining and the black and grey both 7/8 full. Being the 27FB has 39 gal fresh, 37 gal grey and 39 gal black we balance the use with dishwater in the black. So we are confident with our usage that we can camp comfortably with our set up both power and water for 5 days if we have a source of fresh water before we need a dump station. Your mileage may vary. My dream set up is 300AH of Lithium, a EFOY ethanol fuel cell for limited sun power support and a Magnum inverter but as we still have one more kid to get through college I've decided to stick to what we have now. I'll just replace the lifelines when they die. I added a Westinghouse 2200 quiet generator and Micro Air easy start box on the AC recently so we have genny power and can use the AC in an emergency but have not needed them so far. I hope this real world info helps you to make an informed decision. Happy Camping! - Brad

[uncle_bob]

Originally Posted by SuperTrouper

Hi Aspen,

Just back from yellowstone and grand teton with my wife and 14 year old son. We camped dry at Mammoth 4 nights and Lizard Creek 2 nights with 1 night at Grizzly in West yellowstone in between to empty and fill water tanks. So for some real world numbers:

Our system consists of (2) 7 year old lifeline GPL-4CT 6 volt batteries in series, IOTA DLS-45 3 stage charger/converter , Sure-Sine 300 Watt inverter, Blue Sky 3024iL Solar Charger with IPN Pro-Remote interface and (4) 100 watt solar panels all on a 2008 27FB. All solar parts and inverter purchased as package from AM Solar and installed by me. I ran #4 AWG cables from the roof to the charger.

Our power consumption consisted of evening (2) Maxx fan and hood exhaust fan use, interior LED lighting, continuous inverter power charging laptops and cell phones using 120V. We ran the furnace an hour each morning to pull the chill (40 degrees) out of the trailer. My son watched a movie each evening utilizing the inverter/TV combo 2-3 hours). We were gone during most of each day to see the wondrous sights allowing for recharging of the batteries. We had morning through midday sun coverage at Mammoth (we asked hosts for a sunny spot when we checked in) and midday (partial) sun at Lizard Creek. The lowest battery reading on the IPN Pro was 12.1 volt at -69 Amp Hours and 67% charge (theoretically we have 110 AH available). Most days we were recharged by evening except two days when we started the evening at -11AH because of nasty weather in mammoth or limited sun in Lizard creek. As an aside, we utilized paper plates for meals but my wife cooked each day using pots and pans and we utilized glass-plastic ware for drinks. We washed said items nightly in a tub and dumped the tub in the black tank. We showered using brief showers every two days and refilled the fresh water once for the 4 nights at Mammoth and ended up with 1/4 tank fresh remaining and the black and grey both 7/8 full. Being the 27FB has 39 gal fresh, 37 gal grey and 39 gal black we balance the use with dishwater in the black. So we are confident with our usage that we can camp comfortably with our set up both power and water for 5 days if we have a source of fresh water before we need a dump station. Your mileage may vary. My dream set up is 300AH of Lithium, a EFOY ethanol fuel cell for limited sun power support and a Magnum inverter but as we still have one more kid to get through college I've decided to stick to what we have now. I'll just replace the lifelines when they die. I added a Westinghouse 2200 quiet generator and Micro Air easy start box on the AC recently so we have genny power and can use the AC in an emergency but have not needed them so far. I hope this real world info helps you to make an informed decision. Happy Camping! - Brad

Hi

Ok, so with the usual disclaimers about voltages (which we've already gone over in this thread):

You get to 12.1V after using about 70AH. Your batteries 7 years old. Best guess is that after 7 years of use, you now have 70AH capacity left out of the 110AH you had when they were new.

That's not a knock on the batteries. 70% capacity after 7 years is doing very well. The point is that, even with a current based monitor, there still are some basic limits.

Bob

[aspenmeadow]

Thanks Supertrouper for the great info!