Group 24M Lithium Batteries

[al1florida]

Originally Posted by gurroz

Thanks for the feed back. I was planning on running a Victron Battery monitor and a DC - DC charger. We carry a Yamaha 2000 inverter/generator and have a 200 watt Renogy solar suitcase. In addition we use a portable 500 watt solar generator to power the TV at night. Maybe the two Relion batteries will be the answer. We travel 5 months out of the year May - September and boondock a lot (25 nights per month.)

Congratulations on deciding to install a battery monitor. That is the very best investment you need for dry camping/boondocking.
With the battery monitor, you will be able to see at a glance the status of your batteries, the voltage of the battery, the charging voltage, etc, etc.

I think your thoughts of installing a pair of group 24 sized lithium batteries is an excellent idea. It seems like your battery power usage is not really high. Possibly as low as 25-30AH a day. With 150AH of total battery (about 100AH usable) your setup should work very well for you.

Once you install your battery monitor you will know for sure what your power usage is.

One really great benefit of having lithium, is that you don't need to charge the batteries to 100% full. Dry camping 25 out of 30 days a month, that becomes very, very important. Trying to get lead acid back to 100% at least once a week is a real pain in the behind when you use your batteries as much as you do.

About charging from the alternator:
-- Typically the alternator will not supply a voltage over above 14.0v-14.2v unless it is very cold outside. With lead acid batteries (engine starting battery) the charging voltage should rise with very cold temps. (freezing or way below).
-- Your battery monitor will tell you at a glance if your alternator is putting out more than 14.2V.
-- Keep in mind the wiring size between the alternator and the battery will most likely be small enough that even though the voltage at the alternator possibly could be above 14.2v, the voltage at the battery may be a lot less.

I have been using lithium batteries in my RV since Jan 2016. In 2018, I moved them to our new-to-us 2006 Journey which will charge the house batteries from the alternator. I pondered whether to just let the alternator charge or to install the Battle Born isolator. My final decision was to add a on/off switch to the wire going to the pick coil for the solenoid that connects the alternator to the house battery. I just leave the switch in the off position unless I want to charge from the alternator. We have 650watts of solar to charge our 400AH of lithium, so I very seldom (maybe twice in the last 2 years) used the alternator to charge house batteries. We use from about 100AH to 150AH a day in our daily lives in the RV.

[creativepart]

Al, I see a noticeable shift in alternator charging in discussions on forums and elsewhere. Seems a lot of folks are installing DC to DC chargers rather than isolators or switches. They don’t cost a lot more and are better for the alternator and the batteries.

[al1florida]

Originally Posted by creativepart

Al, I see a noticeable shift in alternator charging in discussions on forums and elsewhere. Seems a lot of folks are installing DC to DC chargers rather than isolators or switches. They don’t cost a lot more and are better for the alternator and the batteries.

I agree, looking at the Victron DC to DC charger for $264 versus the Battle Born isolater/charger at $170, the Victron looks very inviting. Also no worries about the proper voltage at the battery. Although the on/off switch is only a few dollars.

[BobC]

There was a question in another thread I was following (I think on IRV2) that raised the question as to how a DC to DC charger would interact with a boost solenoid. Could it handle the relatively high, reverse current flow or would additional circuitry be needed.

[jerichorick]

Originally Posted by al1florida

Congratulations on deciding to install a battery monitor. That is the very best investment you need for dry camping/boondocking.
With the battery monitor, you will be able to see at a glance the status of your batteries, the voltage of the battery, the charging voltage, etc, etc.

I think your thoughts of installing a pair of group 24 sized lithium batteries is an excellent idea. It seems like your battery power usage is not really high. Possibly as low as 25-30AH a day. With 150AH of total battery (about 100AH usable) your setup should work very well for you.

Once you install your battery monitor you will know for sure what your power usage is.

One really great benefit of having lithium, is that you don't need to charge the batteries to 100% full. Dry camping 25 out of 30 days a month, that becomes very, very important. Trying to get lead acid back to 100% at least once a week is a real pain in the behind when you use your batteries as much as you do.

About charging from the alternator:
-- Typically the alternator will not supply a voltage over above 14.0v-14.2v unless it is very cold outside. With lead acid batteries (engine starting battery) the charging voltage should rise with very cold temps. (freezing or way below).
-- Your battery monitor will tell you at a glance if your alternator is putting out more than 14.2V.
-- Keep in mind the wiring size between the alternator and the battery will most likely be small enough that even though the voltage at the alternator possibly could be above 14.2v, the voltage at the battery may be a lot less.

I have been using lithium batteries in my RV since Jan 2016. In 2018, I moved them to our new-to-us 2006 Journey which will charge the house batteries from the alternator. I pondered whether to just let the alternator charge or to install the Battle Born isolator. My final decision was to add a on/off switch to the wire going to the pick coil for the solenoid that connects the alternator to the house battery. I just leave the switch in the off position unless I want to charge from the alternator. We have 650watts of solar to charge our 400AH of lithium, so I very seldom (maybe twice in the last 2 years) used the alternator to charge house batteries. We use from about 100AH to 150AH a day in our daily lives in the RV.

Al, I thought the battery BMS would limit charging once satisfied. I am planning a Lifepo4 Nissan Leaf crash pack upgrade. I see no problem, because of the BMS protection, of doing a plug & play. What am I missing in my thoughts about this type of battery?
Rick

[creativepart]

Most BMS protect against OVERCHARGING. They are not chargers, or charge controllers or smart chargers. That's still up to you to provide with your other charging devices.

Some prevent over temp protection and even fewer provent under temp charging protection.

You keep calling the Leaf cells "Lifepo4" do you mean they are LiPo4 batteries? Or are "Lifepo4" batteries a thing I've not heard of.

Also, since the cells you plan on getting are 8v cells I still fail to see how you plan to operate them in a 12v system. You could put three in series for 24v and then use a 24v to 12v converter or even a 24v inverter. I know you said you'd simply just turn off charging when they reach a compatible voltage. I'm no expert but I still don't see 8v battery packs working as you've described. At 24v, no problem, you'd have minimal hassle making that work.

[al1florida]

Originally Posted by jerichorick

Al, I thought the battery BMS would limit charging once satisfied. I am planning a Lifepo4 Nissan Leaf crash pack upgrade. I see no problem, because of the BMS protection, of doing a plug & play. What am I missing in my thoughts about this type of battery?
Rick

As far as using a battery from an electric car, I am of no help. What I have read about is that these work very well for those well experienced in designing and setting up DIY systems. Also I wonder if the Nissan battery has a built in BMS, or does it depend on an external BMS?
As CreativePart wrote, the BMS is an over charge and excessive discharge protection device. It is designed for protection of the battery. I believe the BMS if used consistently to limit charging discharging it would over stress the battery. Kind of like always taking your auto/truck engine to the max RPMS as you drive. That is, in first gear going to the max before shifting into second gear and so on. Yes you could do that but I wouldn't expect my engine to last as long that way.
Another consideration is: Some BMS require manual intervention to begin supplying power again or being charged. That means you loose all RV battery power until reset.

[BobC]

Here's a link to a huge bus/RV install using Nissan Leaf batteries:

RV Lithium Battery | Nissan Leaf modules in an RV Lithium Battery Beginning from this Morning

There are eight videos, Part 1 - Part 7.5. Part 1 is embedded in the above. If the videos don't daisy chain, here's a link to his channel:

https://www.youtube.com/channel/UC-x...4WbU5cg/videos

[creativepart]

Originally Posted by BobC

Here's a link to a huge bus/RV install using Nissan Leaf batteries:

I've been watching these videos for this past year or so. I believe he created a 48v system out of the Leaf batteries. And his solar is HUGE and on articulated supports that are motorized and extend out from the sides of his bus a couple of feet when extended.

He actually installed a small house window A/C unit in the compartment that houses his battery bank to control the heat of the batteries.

He engineered his system to run the whole bus on battery power - including a large home mini-split A/C unit in another basement compartment.

Here's a link to the specific Leaf battery videos:

https://www.youtube.com/watch?v=K47N...s70cisI9YypeLO

[jerichorick]

Originally Posted by al1florida

As far as using a battery from an electric car, I am of no help. What I have read about is that these work very well for those well experienced in designing and setting up DIY systems. Also I wonder if the Nissan battery has a built in BMS, or does it depend on an external BMS?
As CreativePart wrote, the BMS is an over charge and excessive discharge protection device. It is designed for protection of the battery. I believe the BMS if used consistently to limit charging discharging it would over stress the battery. Kind of like always taking your auto/truck engine to the max RPMS as you drive. That is, in first gear going to the max before shifting into second gear and so on. Yes you could do that but I wouldn't expect my engine to last as long that way.
Another consideration is: Some BMS require manual intervention to begin supplying power again or being charged. That means you loose all RV battery power until reset.

No BMS in packs. Since I posted I have found out a few things. The packs are fairly stable in a wide range of temperatures. (I try hard to stay out freezing temps.) The BMS's I am looking at seem to be self resetting when the charger voltage is present. My inverter will protect the battery bank from going to low critical. So the BMS should never disconnect. The high charge voltage is well below the pack & BMS cut-off. Of course the battery is what would have to reach the extremes that the BMS is supposed to prevent.

I have a call into the ebay supplier of the Leaf G2 packs. I'll let you all know what he says. But I am feeling more and more confident that I can do this with satisfying success to meet my needs. I am not going with solar and I don't do too much extended boon docking. I'll post more later.
Rick

[gurroz]

I thought I would bring everyone up to date with my decision on upgrading to lithium batteries. After input from this forum and additional research I decided on 100 ah Renogy batteries. I use Renogy solar panels and think they build a product. I know Will Prowse was really impressed with the Renogy build quality and only faulted them for not being able to be connected in series. That is not my application. BB makes a fantastic product, however, does not offer a group 24 option. I was also impressed with Dakota which is the only other UL listed lithium battery other than Renogy. At $785 with a coupon code it was a no brainier. I also installed the Victron bluetooth battery monitor at the same time.

[al1florida]

Thank you for coming back and updating with info about your final decision. It is so nice when folks come back and tell us how things turned out.

[jerichorick]

Originally Posted by BobC

Rick,
Keep us posted, I'm intrigued.

Bob, I am starting a new thread so as not to hijack this one. The project is coming along slowly. Some changes have happened. Look for my Nissan Leaf Battery Upgrade thread.
Rick Y

[gurroz]

I thought i would give an update on our energy management after 6 weeks of boondocking. To start with I should say that we camp with our RV, we do not try to live like we do in our SB. We generally travel 3 weeks per month in the summer May - September and return home for 1 week each month. We currently use 1 Renogy 100 AH lithium battery and a Max Oak Bluetti 500W solar generator converter which is a 45 AH lithium battery. We use a Renogy 200W solar suitcase for charging. We are able to move the panels for optimal sun. We monitor our power usage with a Victron 712. We use the Bluetti to power our TV and DVD at night as well as charging phones, computers and other electronic accessories. We do also charge phones in the coach using USB ports. We seldom have to run the generator, it is used primarily to power the microwave, DW's blow dryer and curling iron. We probably have 1.5 hours of usage in 6 weeks. We also use small LED lights inside the coach at night and when sitting outside. Our largest use on our coach battery was 31 AH when the heater came on a few times through the night. The the bluetti used was 30 AH in a day. On average we were using 55 AH per day. We were planning on buying another Renogy lithium battery, however, it appears we have no need. We have not plugged into shore power yet this summer and don't plan too. I know our style of camping is not for everyone. My point is you do not have to spend 10 to 20K on a solar system to enjoy solar power. It can be done on a budget.

[al1florida]

Thanks for the update. It is great to hear how projects work out for folks.

You absolutely show what can be done for a relatively small amount of $ when you research and plan for installing solar and batteries for boondocking or dry camping.

Just as you wrote, you go camping in your RV. You don't run a satellite TV system, the microwave, or other high powered devices from your batteries through an inverter.

Excellent setup.

[Phil G.]

Originally Posted by gurroz

I thought i would give an update on our energy management after 6 weeks of boondocking. To start with I should say that we camp with our RV, we do not try to live like we do in our SB. We generally travel 3 weeks per month in the summer May - September and return home for 1 week each month. We currently use 1 Renogy 100 AH lithium battery and a Max Oak Bluetti 500W solar generator converter which is a 45 AH lithium battery. We use a Renogy 200W solar suitcase for charging. We are able to move the panels for optimal sun. We monitor our power usage with a Victron 712. We use the Bluetti to power our TV and DVD at night as well as charging phones, computers and other electronic accessories. We do also charge phones in the coach using USB ports. We seldom have to run the generator, it is used primarily to power the microwave, DW's blow dryer and curling iron. We probably have 1.5 hours of usage in 6 weeks. We also use small LED lights inside the coach at night and when sitting outside. Our largest use on our coach battery was 31 AH when the heater came on a few times through the night. The the bluetti used was 30 AH in a day. On average we were using 55 AH per day. We were planning on buying another Renogy lithium battery, however, it appears we have no need. We have not plugged into shore power yet this summer and don't plan too. I know our style of camping is not for everyone. My point is you do not have to spend 10 to 20K on a solar system to enjoy solar power. It can be done on a budget.

Your camping style is about like yours - except we're not fortunate enough to be able to do it as many weeks per year. That's a great travel/SB ratio you're enjoying!

We don't need lithium batteries in our RV to camp with, however. We use two Group 31 deep cycle AGM batteries, a built-in Onan generator, a portable Honda generator, and some occasional engine idling to supply drycamping electricity ... no solar is involved or needed. The little Honda or idling of the V10 engine charging methods are both ultra-quiet and can be done just about anytime.

As far as I can tell, AGM deep cycle RV batteries can be close in performance to the much more expensive lithium RV batteries - assuming that the AGM battery weight isn't an issue and that one doesn't want to spend the extra money for the lithiums.

(I also don't care for the reliability implications of all those inter-connections inside a lithium RV battery built in one of the standard automotive battery group sizes. I looked at a cutaway diagram of a 100AH Group 27 size lithium RV battery and couldn't believe the mechanical complexity inside. When is a Group 27 RV lithium battery going to be available that is made up of, say, only six big inner lithium cells?)

[gurroz]

PhilG, I agree AGM batteries can do the job. For us it was also about weight and the speed of charging. Our 1 lithium battery weighs 25 lbs. Our two AGM batteries weighed 120 lbs. The lithium batteries also charge much faster than lead acid and AGM which is a consideration when charging with solar. We have a Yamaha 2000 generator that we take with us when we go to the beach. Solar can be challenging on cloudy or overcast days. The small generator/inverters are very efficient. Solar is not for everyone, however, when you live in the Arizona desert sun is plentiful and free!

[al1florida]

Originally Posted by Phil G.

Your camping style is about like yours - except we're not fortunate enough to be able to do it as many weeks per year. That's a great travel/SB ratio you're enjoying!

We don't need lithium batteries in our RV to camp with, however. We use two Group 31 deep cycle AGM batteries, a built-in Onan generator, a portable Honda generator, and some occasional engine idling to supply drycamping electricity ... no solar is involved or needed. The little Honda or idling of the V10 engine charging methods are both ultra-quiet and can be done just about anytime.

As far as I can tell, AGM deep cycle RV batteries can be close in performance to the much more expensive lithium RV batteries - assuming that the AGM battery weight isn't an issue and that one doesn't want to spend the extra money for the lithiums.

(I also don't care for the reliability implications of all those inter-connections inside a lithium RV battery built in one of the standard automotive battery group sizes. I looked at a cutaway diagram of a 100AH Group 27 size lithium RV battery and couldn't believe the mechanical complexity inside. When is a Group 27 RV lithium battery going to be available that is made up of, say, only six big inner lithium cells?)

If other RV's are boondocking or dry camping and they don't use their generator, please be courteous and don't park within 20-50 yards of them.

You may feel your engine or Honda generator is "ultra quiet", but if your neighbors can hear it then you are disturbing them.

The sound of a Honda does carry 20-50 yards depending on conditions in the surrounding area.

If you run the Onan, then at least 100 yards is best.

[al1florida]

Lithium, AGM, or plain old flooded cell lead acid battery all work well, depending on, how long you go w/o getting your batteries back to 100% full, your power needs and ability to recharge.

In Gurzzo's usage they go w/o hookups for 3 weeks.

If you use any kind of lead acid based battery and you go for 3 weeks, you must get that battery back to full charge every 5-7 days or the battery plates begin to sulfate. Repeat this 1 to 3 week period a few times, w/o getting back to full charge, you will find that you have lost quite a bit of the original capacity of your battery.

If you only use 20% of your lead acid battery you can use a good 3 stage charger and get the battery back to pretty close to 94-97% in a couple of hours.

If you let your battery get down to 50-60% full it takes a lot more time, far more than most people want to run their RV engine or generator.

The problem we all have with lead acid, is the last 15% of charging happens at only a few amps of current going back into the battery. The closer you get to 100% full the less amperage is going back into the battery.

This is where the lithium really excels. There is no need to ever get the battery back to 100%. It is perfectly happy operating between 30% and 90% full or any place in between.

But then the majority of RV'ers don't spend 2-4 weeks continuously w/o connecting to shore power and getting their lead acid batteries back to 100%. So lead acid works just fine for them.

[Phil G.]

Originally Posted by al1florida

If other RV's are boondocking or dry camping and they don't use their generator, please be courteous and don't park within 20-50 yards of them.

You may feel your engine or Honda generator is "ultra quiet", but if your neighbors can hear it then you are disturbing them.

The sound of a Honda does carry 20-50 yards depending on conditions in the surrounding area.

If you run the Onan, then at least 100 yards is best.

Hmmm ...:

1. Our little 650 watt battery-charging Honda is one of the quietest generators ever offered - 56 dB at full power.

2. Winnebago installed our built-in generator properly, so unless one has some kind of paranoid-like noise hangup, it should not be irritating at all - it certainly is not to us inside or outside.

3. The idling Ford V10 engine with it's stock exhaust system can barely be heard 30 feet away (i.e. the blowing wind is louder), and can't be heard or felt from inside our motorhome.

Other drycampers close enough to be bothered by either 1. or 3. above, are probably too close for us too (for other reasons). When drycamping in general, or certainly for drycamping in the boondocks, our preference is to not only not hear other camper's talking/laughing or children or dogs - but to not see them either.

If we add portable solar someday, it will be for low-level charging to back up the little Honda ... not for reduced noise.