[Archived]

How about, yes, no or maybe for an answer to your is lipo=2Xagm ratings.

Here is a good description from barrterystuff.com

“An amp hour (AH) is a rating usually found on deep cycle batteries. The standard rating is an Amp rating taken for 20 Hours. What this means, say for a 100 AH rated battery is this: Draw from the battery for 20 hours and it will provide a total of 100 amp-hours. That translates to about 5 amps an hour. 5 x 20 = 100. However, it’s very important to know that the total time of discharge and load applied is not a linear relationship. As your load increases, your realized capacity decreases. This means if you discharged that same 100 AH battery by a 100 amp load, it will not give you one hour of runtime. On the contrary, the perceived capacity of the battery will be that of 64 Amp Hours. – See more at: https://www.batterystuff.com/kb/articles/battery-articles/battery-basics.html#sthash.efqyh39T.dpuf“

In my opinion, here is another way of looking at it. If after 20 hours you are in dire straits and you need more capacity than the 100 AH that you planned on using, the lipo is not going to help as it is done but the AGM’s will still have 50% some reserve.

BUT…..If you ran the same loads on both the 100 AH lipo and the 200 AH AGM’s (2Xlipo) and they both drew 100 A for an hour, the AGM would behave like a 128 AH battery (2X64) so you would end up with a spent but healthy lipo battery where the AGM has now been taken down to 14% of its capacity (28 AH left after an hour divided by the 200 AH rating) which is destructive for the battery. Tom could probably comment on what thus means to an AGM.

In reality, you use will likely be somewhere between the 1 hour and the 20 hour extremes so using the 100 AH lipo = 200 AH AGM is an easy and practical way to compare the two chemistries.

But there are so many benefits to lipo compared to AGM except for first cost and assuming your charging system will work with the lipo’s.

If you are interested and your charger is not exactly what they specify it may still work since they say that the batteries are a direct drop in replacement for lead acid. It may not be optimal and I would then ask what the impact will be to the batteries using your existing charging system.

[Fred F.]

As someone who actually has them in my coach, I am not totally impressed by them. Yes, they weigh less, but they also add complexity and more items to fail. You have another network to control/monitor the batteries, extra relays to shut them down or turn them on, and just the extra crap inside each battery for monitoring voltage, temps, historical events etc. Mine have not been trouble free, and have been a PITA since getting my coach. Liberty did finally get most, if not all, of the issues resolved late this summer, but I had to fight problems for over a year before they did. I have only made a couple of trips since the fix by Liberty, so I won’t find out until next summer if all the issues are really gone. It is a real problem when you can’t trust that the coach will stay powered up because of battery issues.

AGM’s still have a big advantage in simplicity, price, and a long track record of reliable performance.

[Archived]

Thanks Mark. How long have you had your LI batteriy system?

[Archived]

I know the problems Mark experienced from the beginning drove him and Liberty slightly crazy. There is a lot going on with his Li system and all it takes is something simple as a problem such as a loose terminal and the entire system goes into a defensive shut down mode.

I do think Mark’s problems are now behind him. What should be kept in mind is his system is more highly evolved because his is not the first generation of Liberty coaches to have Li, and when his was built Liberty already had quite a few on the road. But like any relatively new technology there are and will be growing pains.

As a flip phone guy I am likely not viewed as embracing change, which is mostly true. Li is an example of one technology I am going to let folks a lot smarter than me try out first. Nobody has yet convinced me there is any advantage beyond a 300 pound weight reduction to swapping my AGM batteries for an Li set up, which on my coach is going to involve 12/24 volt systems.

I am especially not going to believe anything a manufacturer’s literature says of the product because it is always self serving.

[Archived]

Thanks Mark. How long have you had your LI batteriy system?

We got the coach in May of 2015.

[Archived]

Thanks Mark and sorry to hear about your issues. That has to be incredibly frustrating. Your signature shows a 2011 Liberty, did you buy it in 2015? If so, is the LI system from 2011 or did you buy the system in 2015 for your 2011 Liberty. Sorry for the questions but 4 years can make a big difference in the technology.

I am particularly interested in the 8D size drop in replacement batteries. If a battery has issues it should disconnect from the system and the others are left to do the work. Knowing that it has disconnected is something that I don’t think has been figured out. I saw a battery that had a wifi connection but I cannot seem to find it again.

I need to to see customer reviews to see how things have been working and they seem to be non existent for rv’s but I still on plan on checking the marine industry to see if there are any there. I see little benefit for pole to pole applications but we plan on doing some boondocking. The technology is here but the execution may still be lagging and long term reliability may be even further out. If I cannot get answers then it will be Lifelines again.

It would be nice if Lifeline came up with a LI option.

[George]

Andy,

I know you are embracing this new and exciting Li technology and all the manufacturers promise.

But step back and look at what I presume you have in place in the context of the differences between AGM and Li for your application.

You have more batteries than most so your coach is already set up to boondock better than most. If your definition of boondocking is to stretch the time between generator starts maximizing it by conserving energy it appears you can make use of the existing space your batteries require and get more power storage with Li batteries. I am going to assume they are trouble free.

But as nice as that sounds it is not free. I don’t know how many hours of boondocking you will spend annually but a little work with a pencil will reveal what your cost will be for each recharge cycle saved or eliminated. But keep in mind energy is energy so regardless of time between generator starts the generator still has to shove XXX little electrons back into the batteries so whether it does it more often with AGM or less often with Li the generator is likely doing comparable work.

One thing a lot of folks ignore is they drag along with them a very capable generator that is meant to allow them to live in the luxury a Prevost coach suggests. My idea of boondocking is anything less than 50 amp service and when I am boondocking I have the generator fired up immeciately so I can be a absolute energy hog. My cost to treat myself to an endless supply of electric is less than 1/2 gallon so I don’t care if I have a lot of on board battery power with one exception. I just want enough for those instances when running the generator is not practical to get through the night using some lights, watching some TV, keeping the refrigerator going, and maybe making that cup of coffee. In that context Li is not important, especially since it only seems to reduce weight and maybe go a little longer between charges. For that the economics are not there.

[Jerry]

I bought the coach in 2015 as I stated. The batteries are original and are the Mastervolt brand. I have 3 batteries and 4 inverters (Outbacks). What turned out to be the biggest issue was that there were multiple, and I mean many loose connections in the battery bank. One battery had every connection inside it at the bus bar very loose. The other two had several that were somewhat loose. This was causing all kinds of issues during charging, and even after charging, that would trip the entire battery bank off line in a safety shutdown. Even if the coach was hooked to shore power, the entire coach would shut down. Without batteries, the inverters won’t run, and you need them or else no power.

As you can imagine, it is a rather large issue when everything dumps, and even though it may be able to be reset, it has to be done manually. A couple of nights this past spring, it dumped out either 8 or 9 times each night. I was not a happy camper.

Jeff Rowe did many diagnostic runs, and Liberty finally figured it out during the late summer. They pulled all the batteries out, removed the top covers and went through all the connections on each. Then they had Mastervolt’s tech person log into the coach and run diagnostics on everything. I stayed one extra night at Liberty to make sure everything stayed up and the next morning, they checked it all again. They also did some firmware updates. Since then I have had no issues. I have been keeping a very close eye on temps and voltages on each battery. They are all now very close in both voltage and temperature.

Liberty used the same Mastervolt system, with the usual updates due to production changes etc. until they switched to the Volta 58 volt system. I have heard from numerous people that that system has also had growing pains.

I just don’t see the need to switch from AGM to Li. Run your generator when needed, or plug into shore power and leave well enough alone. You will likely not get the amount of run time you think you will by switching over to LI. I was told it would cost several thousand dollars to rebuild or replace each of my batteries when it becomes necessary. AGM’s are way cheaper than that! And as has been said, the next person to look at your coach may not want them. Then you have another different problem.

[Walter]

Note to Andy… Go dry camp, you have one of the best coaches for battery performance, simple 12v systems that likely can go 12 – 14 hours on inverter with minimal 120v loads and still be above 12v when it’s time to start the gen. I had a 2000 CC and it was a dry camping machine. They’ll work out all the bugs for LI replacing AGM in the future and then the time may be right for a change.

Hug your Lifelines, they’ll be good to you.:)

[Archived]

Jon, when comparing agm to lithium, the energy consumed to charge either is not the same. You can charge the lithiums unitil they are pretty much topped off at the bulk charge rate but with agm’s the bulk charge will only take you to about 80% of capacity and then you need to top them off by going through the absorption cycle which, as you know, is slow and very inefficient. Longer generator run times means more energy was spent charging the agm’s. I can also stop charging the lithiums at any point without any concern about taking life out of them by not topping them off.

If you don’t mind running the generator that is fine but I prefer the sounds of birds chirping or water flowing vs the generator. I would also not want to leave the generator running if I had to leave for the day and if agm’s were not topped off by the time I left it will compromise their life. There is no such concern with lithium.

I’m not knocking agm’s but for my purposes, lithium better fits my needs. I’m not convinced, yet, that the risk is worth it but we will see if things change in another year. With at least three companies making the drop in 8D batteries, reviews have to start surfacing. The specs are all about the same so the competition will be good and should make for a better product.

Mark, it sounds like if the battery connections were done correctly the first time then things would have been much more tolerable. Also, the battery technology has changed very significantly since 2011 as has the quality control. I sell very large energy storage systems and UPS systems and we are battery agnostic meaning we can use the right battery technology for the right application. The smallest UPS systems we sell are 250 kW and our largest to date is 20 MW and one customer has two of these 20 MW systems. These are mostly lead acid but we are having more and more customers transitioning to Lithium ion. A couple months ago I sold a 2.25 MW UPS system to major Univeristy for their new data center and it is expandable to 9 MW and it uses lithium ion batteries. This is a paradigm shift for the data center industry just as it is for the rv industry but the rV industry is running a bit behind still. I think that the marine industry may be a bit further ahead which is nice, if they are, since the batteries are used in a similar application. Time will tell

Thanks Tom. I agree that for a Prevost, it is a good choice for dry camping. The simplicity of the systems (compared to other Prevosts) was a selling point for us – a lot of the systems are also manual.

Out of curiosity, about how long would it take to charge lifelines if the (6) 8D batteries are needing 700 AH to be topped off? The 2 Magnum chargers can each put out a max of 125 A.

If it will help the batteries last another 18 months, I will gladly give them hug but that’s as far as I will go 😉

[Archived]

I don’t think that the batteries have changed that much. Mastervolt still does things about the same way from what I have read on their website. Liberty went to a different supplier for the battery, inverters and generator. Time will tell if that was a good decision or not. One of the reasons was that Kohler quit selling the 20EORD package that has been the generator of choice for years.

You still have to have a newtorking system of some sort to monitor the LI. Not so with AGM. You have far more things to fail with LI. That is not going to change that I can see. The issues with loose connections were inside the battery case. Unless you are going to physically remove the battery and poke around inside of it, you would not know about that as a problem area. Plus the other issues such as realys shutting down made it harder to find. This would not happen with AGM batteries in place.

Our coaches are not built for trying to conserve power. They have all the comforts you could want and battery run hours are nowhere near the top of the list of things they are considering when building one. There is no reason not to run the generator that I can see. I use mine anytime I am not hooked to shore power or driving. The fuel it uses is but a fraction of what you use when driving.

[Archived]

Mark, thanks for your input. If you have seen the inside of the Mastervolt batteries I would be interested in seeing what you think of the construction of the Smart Battery compared to the Mastervolt. If you go to lithiumion-battery.com and as you scroll down to “Video Sources” and watch the short video of how they are made, you will come away with a good understanding to be able to compare the two. I went to the Mastervolt site and there is no detail regarding battery construction so I could not compare the two. That system is much more complex than the design that is being touted by at least three manufacturers (Smart Battery, Relion and Nex Gen) that are claiming direct replacement for 8D agm batteries and that they can be paralleled or put in series. This implies that the chargers should work and the alternator should work without modification. This also means no communications between batteries, no network, no relays and no extra additional monitoring is required but is required for the Mastervolt system. Some specify specific charge settings but that may just be the optimal settings.

I’m I’m not saying this drop in system works but there are three manufacturers that claim that it will and they all show the same specs which gives he some hope. I’m not from Missouri but I think as if I was, which is why I would like to see user reviews of these systems in our type of application or a marine application. I would not consider the Mastervolt system because of its complexity and now because of your experience. But a drop in system?, that has my attention.

Evidently, I’m an outlier in this community regarding running the generator but I am certainly not alone in the rv community which is why many rv’ers consider lithium and solar. My point above regarding the absorption phase of charging was not to make a picky point as I’m not concerned about the additional fuel I would burn but having to listen to that generator for a longer time than I would might otherwise have to. Which is also why I don’t really care about the weight savings. I get that some people don’t mind the noise and more power to you but I would not be happy in my stick house having the neighbor run his lawn mower for hours every morning and then again in the evening for a week or longer. That is why this topic interests me and eventually I will take an interest in solar. As Tom pointed out, my bus is as good of a candidate that you will run across in the Prevost world for dry camping and I would like to take full advantage of that capability.

[Archived]

Most people that are afraid or wish to not run their generator seem more influenced by the cost of diesel than anything else. There are 20 year old coaches with less than 2000 hours on their generator which we know is good for 30,000 to 40,000 hours.

[Chuck]

I belive it Jon but it’s not me.

[Ronald]

I truly believe that we’ll see major advancement towards Lithium Ion technology. The lead acid battery will go away like the tube TV.

We have had no trouble with our LI batteries (3) in two years and 35,000 miles. We are getting close to 300 hours on our Generator.

Within 30 years, I’ll be 88 years old and I think I’ll see a totally electrically powered coach. No Volvo D13, no Allison transmission.

A hydrogen fuel cell generator for charging and powered by Lithium Ion batteries!

The roof will be covered in solar cells, the awnings will have solar cells imbedded in the fabric.

The paint and windows will be impregnated with solar cells….. it’s the wave of the future!

Liberty Coach will have one and it will be called the ‘Liberty Coach Elegant Lady, the Jane Jetson Edition’. :o)

Mark