[Chas]

Am I right in assuming that folks who consider switching from AGM to Li have fully investigated the costs and benefits along with justification?

I am on a lot of bus sites. I have spoken at length to people directly involved in designing Li systems for a coach. I have spoken at great length with manufacturers (not dealers) of Li batteries and systems.

I have come to the conclusion that the myth is they are a direct replacement for an AGM battery. They are not. They do save weight. But they are complex and their systems are complex and very expensive. The cost and complexity increases if the purpose of a Li system is to be able to dry camp for longer periods. So I would really like someone to do a side by side comparison of costs as well as defining the benefits so the cost of the benefits can be evaluated.

Right now we typically have batteries with a 5 year life and proven reliable systems to manage the power from those batteries. To charge the AGM batteries it costs us a little shorepower, or a couple of hours of generator time. In short I suspect on average, including the cost of batteries and the diesel fuel to run the generator averages $700 per 5 years, per battery. Maybe a little more. If a person does not dry camp, or if the person does, but wants to run the generator a lot one house battery is all that is needed. But on average I just don’t see a huge cost associated with AGM, and little if any benefit from LI except weight savings.

[Archived]

The AH rating is a representation of how much a battery can be discharged at a certain rate of discharge.

Compare it to the gas in a fuel tank. The rating of MPG for a car is based on some standard to represent typical driving which can be compared to the rate of discharge. The amount of fuel in the tank can be compared to total AH.

Where both values are meaningless is if the discharge rate (in the case of the battery) or the fuel consumption (in the car) is at a greater rate. And even though my car has a theoretical capacity of 20 gallons and I get 20 MPG, I cannot use its theoretical range of 400 miles, so I refill the tank (recharge) while I still have a lot of fuel such as 1/4 tank.

[Roger]

Been reading about Battery Amp / Hrs . Dis regard previous question on 2 – 6 Volt in Series / Ah .

Two 6 volt 400ah Batteries wired in series will give You 12 Volt and 400 Ah . To increase Amp Hours , Wire 2 12 Volts Parallel. (2) 12 Volt ‘s X 250 Ah will get You 500 Ah.

Question here for me to try and understand this whole Amp / Hr thing .

If You have a 250 Ah Battery , and can only draw it down to 50% , Are You really only getting 125 Ah of actual use out of that Battery ? Is this correct ?

Thanks ,

Rocky

[DON]

Rocky,

I bought a new Silveron in 1976, it was a great boat.

If you need battery prices, contact me.

[Chas]

Tom,

What are Your thoughts on (2) 6 Volts Wired in series the way they are on the Silvertons. Verses An 8 D ?

Lifeline has some impressive sounding 6 Volts.

Thanks,

Rocky

[Chas]

Rocky,

Lifeline 6v range from 220 amp hrs to 400 vs the 8D at 255, so in series you can get as much bang for the buck in amp hrs as you want. I think the deciding factor is battery tray space and just how much amp hrs you actually need. If you look at cost alone, that may help in the decision.

4CT 275.34

6CT 3470

L16 526.88

[Archived]

Tom,

So If I understand all of this Correctly 8D 225 Ah-112.5 Usable Vs (2) L16T’s. 400 Ah -200 Ah Usable

With reserves Being 8D @ 25Amp Draw = 475 Minutes , Which 50% of that 237.5 Minutes / 3.9 Hrs

Reserve of (2) L16T’s @ 25AmpDraw = 950 Minutes , @ 50 % Draw = 475 Minutes / 7.9 Hrs

Cost of 8D $ 6000 and Cost of (2) L16T’s – $1,0520 Additional $4520

Weight of the 8D is 162# and weight of (2) L16T’s 238 # Additional 76#

The Dimensions Might be a factor With the 8D being 20.76″ Long x 10.89 Wide x 8.60 High

And the (2) L16T’s adding up to 23.28″ Long x 13.9″ Wide x 15.73″ High ?

Of Course this is for one 8D , If You done Line 1 that has the Refridgerator and most of the goodies on it. (Line 2 in My Coach just seems to be an afterthought, Not too much riding on it ? ) Would be an additional cost of $9040 and $18080 for both line 1 and line 2 ?

Would almost double the time for Boondocking wouldn’t it ?

Of Course , Could save the Extra Dough for Wheels like Buddy’s ! HA !

[Steve]

I was not planning on doing a cost comparison on LI vs AGM until about a year from now which is when I would plan on changing out the Lifelines but with the latest round of discussions it was bugging me so I did. This comparison is for my coach and my needs. It does not consider the reputation of the manufacturer or their products but does use their claims. I personally would not consider Starlight for many reasons but would consider looking into companies like Smart Batteries at lithiumion-batteries.com or Relion. For this excercise I used the Smart Batteries technology and prices. I have (6) Lifeline 8D batteries rated at 255 AH each for a total of 1,530 AH. Using Jon’s rule of thumb for maintaining a reliable bank for 5 years I would only consider using a max of 1/2 of the capacity or 765 AH. Personally, I will pay for someone else to install the Lifelines and they can deal with disposal and the risk of injury. So I figure 2 hours (@$120/hr) worth of labor to swap out the batteries, clean the terminals and properly torque the connections. I’ll ignore the initial installation so for years 5 and 10 the combined labor will be $480. For the batteries: (6) @ 600 each = $3,600 over 15 years it is $10,800 again, this is using Jon’s method of comparison. Total over 15 years for labor and materials is $11,280.

The Smart battery costs $3,000 for a 12 vdc 8D 260 AH direct drop in replacement. The 260 AH rating is all completely usable so I would need (3) batteries for 780 AH to match the 765 AH of the Lifelines (at 50%). Apples to apples AH hour comparison is $11,280 – $9,000 = $2,280 benefit for the LI.

Add an additional battery for a total cost of $12,000 and now the Lifelines are ahead by $720. Per year, this equates to a difference of $48 per year. But you will run the generator less, use less fuel while travelling (lighter weight) and avoid the hastle (especially as a full timer) of having to order and install the new batteries. Now I have an N+1 system that can be taken down to a 32% of discharge in comparison to my exising system with no ill effects. It will also help offset any reduction that will likely occur over 15 years. However, you can always add another battery.

They also have a 300 AH version, for whatever it is worth, at a cost of $10,500 (for three).

These batteries will shut off at 8 vdc so generator auto start will not be a problem. They also turn back on when they see a charge voltage. Set your charger to the following settings: Bulk at 14.4 vdc, absorption at 14.6 vdc and float at 13.6 vdc.

Lifetime Limited Warranty is 5 years non prorated and will cover the repair or replacement at no charge (less shipping). In the rare event that it is not repairable after the 5 years, you can buy a new one at 35% of the price of a new one. Obviously their verbiage is longer but worth checking out if you are interested.

If I sell my coach, those batteries are coming with me and in their place will be brand new of whatever makes sense to me at the time.

I like the construction of the battery and their video is worth watching but I would like to see one in person. For those that may hold a similar interest, they will be at the Electric and Hybrid Marine World Expo Show in Tampa January 16th – 18th which coincides with the Prevost-Stuff Show. I am going to try and attend.

[Ronald]

Andy,

Based on your research can the existing inverters/chargers be used with the new li batteries or does that stuff need to be updated as well. Last I heard it wasn’t as simple as just dropping in new batteries but that was a while back.

Bill

[Dick]

I’m confused Andy. If Li batteries maintain a constant voltage until shut down, how do you set the trigger point for auto-start? What am I missing?

[Archived]

Bill, if you can program your chargers to the reccomended settings above they should work. My Magnum 2812 inverter/chargers should work fine and they actually show the remote that I have as an example on their website. Before I bought the Magnums, I asked Invereter Service if there were any limitations with them in working with LI batteries and they said no. I’m not sure if my old Xantrex’s would have worked but they were replaced before I had much experience with them. These batteries may also work on 12/24 vdc systems but I do not have such a system and do not plan on doing the legwork to see if they would. There are now RV manufacturers that are now using these batteries as well as the Relion batteries in their newer offerings. This is no longer theory – they are here and they are working but the long term reliability has yet to be proven out. It seems to be a large company that has invested for the long haul so I plan on considering them when the time comes. The benefits are extraordinary compared to AGM but again, the long term has not been proven out or maybe it has in other industries and we are just running behind a bit.

[Archived]

I’m almost as much of a cynic and skeptic as Jon when it comes to this new technology … I switched from a flip phone to a smart iPhone in the fall of 2015 after the flip phone fell apart.

But I do have an open mind to new things. There have been two huge technological changes over the last few years: LED lights and Li-Ion batteries. Both started out slow because they were “new”, relatively expensive, and weren’t necessarily simply plug and play. The cost of LEDs have continued to drop and provide us with light at a small fraction of the cost (in watts) of incandescent lights often with an extremely long life and without the accompanying heat and High capacity batteries (first Ni-Cads and now Li-Ion technology) have revolutionized the power tool business and in turn many of the building and construction trades that use them.

Now that Chevrolet, Toyota, and Tesla have established electric cars as fairly viable we can look for significant advances in Li-Ion battery technology and the accompanying technology to successfully manage that technology for many different applications. Perceived volume by manufacturers will drive significantinvestments in battery and battery management R&D in the short-term. There will be scale.

This will pay dividends for the RV industry and not just what I’ll refer to as the luxury market (38′ and up). The benefits will cascade down through the smaller units which will really drive volume.

I think the advances will shortly reach critical mass and the issues that Jon rightly brings up will be addressed. The end result will likely be that when its time to replace our aged out AGM batteries it will be more than cost effective for many of us to retrofit our coaches with Li-Ion batteries and associated battery management system. Less weight, more juice (amp-hours?), faster recharge, deeper safe discharge, fail-safe discharge protection, and easy auto generator start-up will likely be part of these systems. The market will demand all of this and the battery folks will provide it. Remember this thread is OVER three years old!

I hope there aren’t any false starts with manufacturers whose products don’t deliver or provide marginal technology that we might get stung on. I just hope we don’t have a BD-5 experience along the way.

I predict that in the not too distant future Jon will have Li-Ion batteries in his coach that Tom and Jeff will try to control with Tom’s flip phone. I expect their hurtle will not be the flip phone itself, but the fact it lacks a color display.

[Walter]

Jon, LI batteries maintain a fairly constant voltage until they don’t then they drop like a rock. Go to shop.relionbattery.com click on 12v Lithium-ion Batteries then click on the 12V 260AH battery then at the bottom there is a ” CLICK HERE FOR FULL SPECIFICATION SHEETS ON RELION BATTERY” that will take you to the discharge graph. That curve is fairly typical.

I still have a few questions but it certainly looks a lot more promising than what I first expected. I’ll probably revisit this in about a year. There is still so much for me to learn about the rest of the systems.

[Chas]

If you have a 200 amp hour AGM battery, and should only run it down to 50% does that mean you sort of really have only 100 amp hours available to you?

I know with lipo batteries you can use them pretty much all the way. Would that mean a 100 amp hour lipo would be about equal to a 200 amp hour AGM?

if

Why are are these batteries’ capacity spoken of as Amp hour and the capacity in electric cars is in kilowatt hours?

[Archived]

The technology is still changing on Li and therefore with that change comes the way we control it via safety features is changing. Also with this change comes dimensional changes to the actual battery. So if you do Li then when they fail/age out you may have to do more than simply replace the batteries. Also as a note then no one really wants your old Li batteries, however your AGM style battery has a core value…Yes you may be able to have your Li rebuilt, with considerable down time….Also note that your Li manufacture could be either out of business or I think as time goes bought out by another manufacture….

I have seen first hand how much work it is to make changes like this….Liberty went to Mastervolt Li and with any change comes testing to get the systems all working together….Now with the change made to Volta systems with the differant voltages etc….

Warranty, many of the Li manufactures offer a 1 year warranty, therefore out of that 12 month period you may have to deal with buying another battery if there are issues….It is hard enough to get service on your coach around the US, then throw in Li and trying to find someone to work with this and have parts….

Li brings a lot of things to the table for options with our coaches….however as motorhome owners for the majority, run pole to pole, and have very little mileage on the main engine as well as very few hours on the generator…..

If you are electronically savy and want to do Li, go for it, remember the next guy might see it as a expense for future service they do not want…