Lithium Ion Batteries for My RV

[fulltimerbob111]

The cost of my system is spread out over 10 years. My first purchase was on my fifth wheel camper in 2005. Then we bought a motorhome and joined our systems to one rig, so it was some of hers and some of mine. Then we added more over the years and upgraded more panels so it would be hard to come up with figures of cost over the years. Batteries over the years 8 AGMs then 6-L16 Trojans then the lithiums.

Our system is a total of 7 panels on a rack that lifts for winter sun and one flat on the roof.

 

Magnum 2800 inverter

Magnum 100 amp controller

7 panels 1-36volt 1-24 volt 5-12 volt all wired in series for a total of 165 volts DC going down to the controller at 1100 Watts.

500 amps I am describing our line of GBS Lithium batteries. The official name for our battery is Lithium Iron Manganese Phosphate batteries (LiFeMnPO4), or simply referred to as LFMP. LFMP batteries are safer than most others you may have heard of. GBS batteries have a Patented Safety Vent. They will not explode or catch fire due to the 2nd generation safety valve.

 

Total cost over the years is over $10 thousand with labor and parts. But I can not break down the money we have saved by boondocking over this time period but we seldom plug in even when we're in our home park in Yuma at Kofa and when we travel for the summer we seldom stay in an RV park we use our Solar system to run the rig. This alone is what makes solar worth the money to be FREE of crowded campgrounds and free space to park can't put it in a dollar amount. Our average cost per year for camping is under $2000 hard to beat. SOLAR Travel FREE

[oldjohnt]

BPf, I like your philosophy as far as the long term convenience and freedom of Solar in general REGARDLESS of cost and payback within reason of course. Its hard to put a price on the freedom solar affords if you're like us and enjoy boondocking in the Utah and Colorado mountains on BLM, Natl Forest and other dispersed locations at elevations with warm days and cool nights. Our energy needs are minimal but we have sufficient solar and battery capacity to pretty well camp indefinitely unless it were to rain for days on end AND THATS WORTH A TON IN OUR MIND.

 

 

Enjoy happy, safe and self sufficient travels

 

John T

[Al F]

We have 7 panels wired in series a bunch of new and old that do the job of recharging.5 panels our on a rack that tilts and two that lay flat.We go north in the summer this year going all the way to Alaska.

Are all 7 panels wired in one series string or in a parallel series setup? If the 2 panels laying flat are in series with the 5 tilted, you probably are not getting all the power you could be. I started a new topic here to discuss tilting of panels in series.

[JCTex]

I'm in the process of changing out my batteries and am struggling with LiFPo or AGM. Everything goes fine in my analysis of Lithium until I get to the temperature problems. I have no place to install them inside my motor home where my HVAC can protect. The bank will have to go down below where my batteries are now.

 

It's my understanding that LiFPo's really don't like heat, even as low as 95*. Damage can be don't in an unforgiving way pretty quickly, I've read. AGM's don't either; but they are more forgiving. I think I could accept that risk by installing 2 or more 5" low volt fans themically controlled. Although it might just move hot air around, if I could get an exchange of air going, I'd be willing to try it.

 

Even worse is the cold. I've read you DO NOT allow them to re-charge at 32* and lower. They can fail and again unforgivingly. AGM's don't like cold; but it won't kill them to,receive some recharge current. I've thought of using electric blankets and similar outdoor heating devices, all themically controlled. This is an attempt to save them if I forget to turn off the solar input, which I will eventually forget to do.

 

I don't think either of these concerns are urban legends. If I spend 2x the money of AGM's, I want some assurances I won't loose my money quickly.

 

Those of you who have installed Lithium down below in a bay, or are planning to do so, what are you doing for extreme temp protection? You 5er folks may have it easier because you can more easily heat and cool your battery compartments.

 

JC

[Ronbo]

I picked up my LiFeMnP04 batteries on Wednesday. I asked if the BMS had protection built in for freezing and high temps. I was told in will disconnect at 32 to prevent charging and there is also an upper limit. None of their batteries have ever tripped the upper limit relay.

[reed and elaine]

Have a remote thermometer in forward bay of fifth wheel where LFP battery bank is located $15 at Home Depot). Temperature has never gotten above ambient (max of 95 C). Have 12 V outlets for 12V fans (10 W) for cross ventilation. Can put in 30 W lamps to keep it warm.

 

We did leave 5th wheel at older son's place at 7500' where it got down to -20F with no degradation in battery. Only draw were parasetics which were perhaps 300 W-hrs a day out of 9 kW-hrs storage so C rate of charge was minuscule. Problem probably occurs with high rate of charge

[Daveh]

I have not been in very hot temperatures so far and we really try to avaoid heat. We have had a few nights where the temp is going below 32 and I will turn off my charger and unplug my solar for those short time periods. I still use the batteries. I just don't charge. I have not been in temp extrmes so not monitored the temp carefully but it seems that my forward bay always has a more moderate temp than outside temps as it picks up some of both the interior heating and AC.

[Al F]

I'm in the process of changing out my batteries and am struggling with LiFPo or AGM. Everything goes fine in my analysis of Lithium until I get to the temperature problems. I have no place to install them inside my motor home where my HVAC can protect. The bank will have to go down below where my batteries are now.

 

It's my understanding that LiFPo's really don't like heat, even as low as 95*. Damage can be don't in an unforgiving way pretty quickly, I've read. AGM's don't either; but they are more forgiving. I think I could accept that risk by installing 2 or more 5" low volt fans themically controlled. Although it might just move hot air around, if I could get an exchange of air going, I'd be willing to try it.

 

Even worse is the cold. I've read you DO NOT allow them to re-charge at 32* and lower. They can fail and again unforgivingly. AGM's don't like cold; but it won't kill them to,receive some recharge current. I've thought of using electric blankets and similar outdoor heating devices, all themically controlled. This is an attempt to save them if I forget to turn off the solar input, which I will eventually forget to do.

 

I don't think either of these concerns are urban legends. If I spend 2x the money of AGM's, I want some assurances I won't loose my money quickly.

 

Those of you who have installed Lithium down below in a bay, or are planning to do so, what are you doing for extreme temp protection? You 5er folks may have it easier because you can more easily heat and cool your battery compartments.

 

JC

I assume your battery compartment is totally enclosed, not exposed to outside dust, water, etc. You can place your lithium batteries on 1/2" or 1" foam pad for insulation and a couple of 12V incandescent lights to help keep the battery temp above 32*. Keep in mind it is not the outside temp below 32*, but the battery temp.

 

I installed my lithium batteries in a large storage bay, along with the inverter & solar controller. Photo here near the bottom of the 1st page of the forum topic. About 2 weeks ago we stopped overnight near Gallup, NM and the morning temp was 9*. The floor of the storage compartment was ~28* so I wasn't worried about the batteries getting below 32*. We were not hooked to shore power, so no charging until the sun came up and started warming everything up and the solar panels started working. Now if we were to camp where the temp was going to stay in the teen's or low 20's for 24 hours or several days then I would be concerned. However I don't see us boondocking for any length of time in those temps.

[Dale P]

Thank you, and no I did not read part 3 of the series. Again I thank you for pointing that ouot

[Ray,IN]

Sounds like a very nice set up. When my bank is ready to be replaced, I am definitely going lithium. My current 900+ amp hour bank should have 5 or so years left in it easy. Hopefully the price of lithium will keep dropping with all the new technologies and it will only cost me an arm and I can save my leg for something else when I am ready to switch.

I just read that the price of raw lithium is rising quickly because of demand.

[lappir]

I just read that the price of raw lithium is rising quickly because of demand.

And I'm sure people with no use of it will buy as much as they can to hold on to until the price tops off and then sell it so the price drops and the manufacturer will be unable to stay in business due to price manipulations.

 

Rod

[jammer1]

I have decided on a modest solar + lithium battery system, probably a 265 watt panel (8.56 amps, 31 v)

and 200 ah battery bank. What kind of controller is appropriate? I assume MPPT is necessary. Would the Blue Sky 2512ix or the Tristar MPPT 45 work?

 

I realize the wattage is lower than most full-timers recommend, but we do not boondock for extended periods, and I have calculated our needs. Our rig (PrimeTime Crusader fifth wheel) has all LED lights and propane operation of frig and water heater. We will not use air or microwave while on solar.

[VallAndMo]

Howdy,

 

I have decided on a modest solar + lithium battery system, probably a 265 watt panel (8.56 amps, 31 v)

This one from Grape Solar/Home Depot? I have seen it too but thought it too expensive in a $/Watts basis: 330/265= 1.25

 

I would rather go with 3x Renogy 100W panels, which at 3*120= $360 would be 360/300= 1.20 $/Watt, and being smaller would be easier to arrange in a way to better utilize roof available space (and avoid vent shadows etc). You could connect them in series and use your planned MPPT controller (below), or connect them in parallel and use a cheaper PWM controller (albeit with larger AWG wire from the panels to the controller). And it would have the added advantage that, if one of them gets shadowed, the total output wouldn't suffer too much.

 

and 200 ah battery bank. What kind of controller is appropriate? I assume MPPT is necessary.

AFAIK, MPPT is *desirable* for better efficiency due to your panel generating higher voltage than your batteries, but it's not really *required*.

 

Would the Blue Sky 2512ix or the Tristar MPPT 45 work?

No direct experience with either (actually no direct experience with anything, as I'm still in the research phase for our system), but from what I've read, the Tristar would serve you well, and it has a better reputation that the Bluesky while still not costing too much.

 

I realize the wattage is lower than most full-timers recommend, but we do not boondock for extended periods, and I have calculated our needs. Our rig (PrimeTime Crusader fifth wheel) has all LED lights and propane operation of frig and water heater. We will not use air or microwave while on solar.

A 200AH LiFePo4 battery bank, used within reasonable parameters (80% DOD) will offer 160AH usable. AFAIK, your planned solar panel and controller should be able to recharge that fully at least once a day.

So if your usage per day is lower than those 160AH, you should have no issues.

 

Cheers,

--

Vall.

[Al F]

I have decided on a modest solar + lithium battery system, probably a 265 watt panel (8.56 amps, 31 v)

and 200 ah battery bank. What kind of controller is appropriate? I assume MPPT is necessary. Would the Blue Sky 2512ix or the Tristar MPPT 45 work?

 

I realize the wattage is lower than most full-timers recommend, but we do not boondock for extended periods, and I have calculated our needs. Our rig (PrimeTime Crusader fifth wheel) has all LED lights and propane operation of frig and water heater. We will not use air or microwave while on solar.

Do you have an inverter? If so, what size? You don't mention wanting to use any AC appliances, i.e. TV, computers, etc. If your AC power demands are truly very low consider going with a couple of 100 watt solar panels like these from AM Solar in Oregon. The ship via UPS so shipping charges are much lower than the 265 watt panel you are considering. You can couple the panels with a non-MPPT controller as well.

 

Have you calculated your Amp Hour (AH) usage to determine how much capacity you need?

[Jack Mayer]

Make sure when comparing costs of panels that you compare the cost delivered to your location. For the number of panels you want.

[reed and elaine]

Have been considering a used Roadtrek as adjunct to our travels with 34' fifth wheel. So many places in Yucatan and the rest of Mexico that a smaller vehicle would work.

 

Find out that Roadtrek apparently has some vehicles (about 5 times our projected budget) that supposedly have 20 kW-hrs of LFP, which is about 500 pounds. Crumbs, you would take a lot of hours to charge that much energy.

 

Reed and Elaine

[VallAndMo]

Howdy,

 

To whom it may interest, just stumbled on this interesting Starlight Solar item sale on eBay: http://www.ebay.com/itm/121878169581

 

Cheers,

--

Vall.

[Daveh]

Description contains these items and does not reflect understanding of their product:

 

• Can be completely discharged without harm

• Withstands much higher temperatures than lead batteries

[Daveh]

This just seems like really dangerous language. There are so many strong selling points of LiFePO4. Why go here? Yes lead acids go dead but so will LiFePO4 with phantom loads. This is not an install it and forget it product!

 

One of the most important aspects of using our battery in an RV is the ability to turn off the battery and walk away. You can come back many months later and the battery capacity is basically where you left it. For an RV in storage, this means no more worry about how to care for the battery. Every week we have customers that come to us with ruined batteries from storing them. Lead acid batteries need lots of attention to make them last, our LFMP battery does not.

[reed and elaine]

If battery is turned off, then there should be no phantom loads. If not turned off, then those one to five watt loads will drain the battery suite

[Ronbo]

It. Is $100 cheaper at elite power solutions

[reed and elaine]

Looking at used Class Bs yesterday and a fairly new Pleasure Way had a 2.4 kW-hR LFP

[Yarome]

Looking at used Class Bs yesterday and a fairly new Pleasure Way had a 2.4 kW-hR LFP

 

That's fairly reasonable/solar sustainable for the type of camping you folks enjoy. I would be really checking on the make, bms, and chemistry though. As time goes by it's becoming much clearer about which chemistries are proving themselves and which are just flat out not delivering.

[AshleyDanh]

I agree with you.

You are going on the right way.

[reed and elaine]

Yarome -

Looking up Lithium batteries and found this older thread. As usual, read each post.

We purchased the 2002 Roadtrek. Son designed and fabricated system:

415 W of solar: 315 W and 100 W panels which required two controllers. Real estate is extremely limited on Roadtrek and wife loves Fantasticfan - so that remained (taking up a lot of space). I do like the way that fan does cool things down in the eening.

2.5 kW PSWI

Two Manzanita Micro LFP batteries of 180 amp (12 V nominal) each in parallel for approximately 4.5 kW-hrs storage (5th wheel system has four of these batteries in series for 48 V (nominal) ). Roadtrekdoes have on-board 2.5 kW Onan. Nice to have; used twice in one year of travel when we were under trees and it was raining in Labrador and and than in Cristobal de las Casas, Chiapas.We took it on 14 week trip to Labrador and Newfoundland. Lots of place to boondock through use of ioverlander.com. Then spent 14 weeks in Mexico. Great places to visit in a Class B that would never have been possible in 5th wheel (Mike and Terri Church's Guide to RVing in Mexico suggest nothing longer than 21' in San Cristobal). Did use power on beach in Yucatan but worries of dirty power had us only use cable through battery charger to battery suite and then PSWI/12 V. Did try using line power on coast but power was ungrounded and got shocked touching vehicle. So we stuck with solar and battery the next four weeks.

So, over 30 weeks traveling in 19' Class B and we are still speaking to each other and happily married - one never knows

Reed and Elaine