RoadTrek's EcoTrek

[Jostalli]

Originally Posted by avanti

I repeat my question: Why should we believe you and not others who make exactly the same kinds of anecdotal claims but with different conclusions? I am not saying you are wrong, I am just not convinced by anecdotal evidence, even "years" of it.

I don't want to "believe what I want", I want to know the truth. The only path to truth is science. I doubt that much actual science is available from any source except the engineers who designed the cells.

I think you are giving too much credit to manufacturer specs. I like manufacturer specs but until I test for myself and read what others have seen I don't fully trust them. This is why I read everything I could find on LiFePO4 batteries before I decided to go with them. Now that I have the cells and a nice power supply I have tested and will continually test each cell to validate what I have read.

Since we are making packs from multiple cells and using several different charging methods the cells can change voltage. That's why a BMS is usually recommended. The reason Terry, the author from the article I posted learned to not charge to 14.6V is because at higher voltages it was causing his packs to become unbalanced. At a lower charge (IIRC 14V) his packs were staying balanced. He even sets his BMS to do no automatic cell balancing (and he hasn't needed it for 500+ cycles). Most BMS cell balancing methods use shunt balancing, which is not the best method of balancing cells.

Can you charge your LiFePO4 pack to 14.6V? Yes. Should you? Not from the data I have read.

[booster]

That looks like a 14.6v power supply. No stages (not necessarily bad), no temp compensation that I saw, no shut off when batteries full (not good, must be counting on the BMS doing that.

Others may know more about it, but doesn't look like anything special to me.

[Davydd]

There is only one serious competitor out there with lifpo batteries that I am aware of that Jim Hammill seems to dance around. Just a reminder to Roadtrek about that "tiny manufacturer”. They published this 9 months ago and have had LFP Class Bs in customers hands for 7 months now and before the Roadtrek test units. They called theirs ecoOasis. Reading it will sound familiar to something Roadtrek just announced. Hmm, who copies who?

http://www.advanced-rv.com/go-farther-grid/

And here people is an out and out lie or benefit of the doubt total ignorance again.

Jim Hammill So when you are buying Solar, does it work at the same time as the other charging sources? Ours does. Ask that question, because I guarantee it does not on other units. Is it a quality panel and quality charge controller? Make sure it is.

Sorry, I can charge simultaneously via solar, engine generator and shore power. I should ask in turn, just one charge controller? To maximize my three solar panels I have an MPPT controller for each panel. That’s three. Also each panel is partitioned so shading part of the panel does not affect the whole panel performance.

Jim Hammill When buying lithium based batteries,,ask yourself this. Is it a lithium battery with a different companies battery management system on it? What does battery management system mean exactly? Can they explain what it means? Does it control battery temperature or does it stop the battery from working if temperature is to high or low? Does it control charging parameters and make it safe? Does it protect your cells from damage? How does it do that?
The answer to most of those questions is...simply put, they don't, because they are modules bought for race cars that have been tossed into an RV, by an owner or a tiny manufacturer.

As an experienced Advanced RV customer, I think I can answer in a positive light to all those questions. I don’t know where the “race car’ comes from. Put the shoe on the other foot. How does Roadtrek do it? Of course Roadtrek is still pulling the proprietary card. Never mind. Some manufacturers are not so secretive in that they put their system on display for customers and non-customers alike (Advanced Fest) and participated in TheFitRV’s video explaining it all in layman terms. Again as a reminder.

https://www.youtube.com/watch?v=prhTC7ukK-o

Of course we may never know what Roadtrek actually provides as it is “proprietary” but of the stuff one can actually see and compare I can guarantee you there is not a lot in a Roadtrek up to the quality of an Advanced RV.

Disclaimer. I’m writing for myself under no false pretenses. I’m just a customer of Advanced RV. I have no association with them or privileges any different than any other customer. However, I am an enthusiast of the company because they are the true passionate innovators, listen to their customers and do their best to satisfy them. No doubt about that.

[bobojay]

Originally Posted by Davydd

There is only one serious competitor out there with lifpo batteries that I am aware of that Jim Hammill seems to dance around. Just a reminder to Roadtrek about that "tiny manufacturer”. They published this 9 months ago and have had LFP Class Bs in customers hands for 7 months now and before the Roadtrek test units. They called theirs ecoOasis. Reading it will sound familiar to something Roadtrek just announced. Hmm, who copies who?

http://www.advanced-rv.com/go-farther-grid/

And here people is an out and out lie or benefit of the doubt total ignorance again.

Jim Hammill So when you are buying Solar, does it work at the same time as the other charging sources? Ours does. Ask that question, because I guarantee it does not on other units. Is it a quality panel and quality charge controller? Make sure it is.

Sorry, I can charge simultaneously via solar, engine generator and shore power. I should ask in turn, just one charge controller? To maximize my three solar panels I have an MPPT controller for each panel. That’s three. Also each panel is partitioned so shading part of the panel does not affect the whole panel performance.

Jim Hammill When buying lithium based batteries,,ask yourself this. Is it a lithium battery with a different companies battery management system on it? What does battery management system mean exactly? Can they explain what it means? Does it control battery temperature or does it stop the battery from working if temperature is to high or low? Does it control charging parameters and make it safe? Does it protect your cells from damage? How does it do that?
The answer to most of those questions is...simply put, they don't, because they are modules bought for race cars that have been tossed into an RV, by an owner or a tiny manufacturer.

As an experienced Advanced RV customer, I think I can answer in a positive light to all those questions. I don’t know where the “race car’ comes from. Put the shoe on the other foot. How does Roadtrek do it? Of course Roadtrek is still pulling the proprietary card. Never mind. Some manufacturers are not so secretive in that they put their system on display for customers and non-customers alike (Advanced Fest) and participated in TheFitRV’s video explaining it all in layman terms. Again as a reminder.

Of course we may never know what Roadtrek actually provides as it is “proprietary” but of the stuff one can actually see and compare I can guarantee you there is not a lot in a Roadtrek up to the quality of an Advanced RV.

Disclaimer. I’m writing for myself under no false pretenses. I’m just a customer of Advanced RV. I have no association with them or privileges any different than any other customer. However, I am an enthusiast of the company because they are the true passionate innovators, listen to their customers and do their best to satisfy them. No doubt about that.

Thank you David!

[Davydd]

I have a question about that lengthy article on lifpo batteries. The author consistently says the batteries exist best at a 50-60% SOC. What is the source for that opinion? I see the description about the "knee" chart so would assume they would live best anywhere in that range before the drop off at both ends. Does it really make a significant difference given the high cycles of lifpo batteries that I doubt most users will ever approach as the author said? Anyway, I think when on the road in a Class B it would be nearly impossible to exist around 50-60% given that driving charges rather fast. Is that just a yachting fact of life?

[BobB]

Originally Posted by Davydd

Anyway, I think when on the road in a Class B it would be nearly impossible to exist around 50-60% given that driving charges rather fast. Is that just a yachting fact of life?

Maybe because when we sail, we turn the motor off and we try to sail as much as possible

Only time, on a sailboat, we turn the motor on is (1) entering/leaving anchorage or dock (2) to charge the batteries (3) absolutely NO wind and we want to get somewhere. Most boats I have been on have had either flooded cells or AGMs. When voltage drops below a certain level, an alarm goes off, you start the motor, charge about 1-2 hours per day. This is on boats with no solar or wind generators. Many cruisers have those, most charter boats don't.

[booster]

Originally Posted by Davydd

I have a question about that lengthy article on lifpo batteries. The author consistently says the batteries exist best at a 50-60% SOC. What is the source for that opinion? I see the description about the "knee" chart so would assume they would live best anywhere in that range before the drop off at both ends. Does it really make a significant difference given the high cycles of lifpo batteries that I doubt most users will ever approach as the author said? Anyway, I think when on the road in a Class B it would be nearly impossible to exist around 50-60% given that driving charges rather fast. Is that just a yachting fact of life?

In the article he said that the 50-60% was when not sailing, or something like that. So it would be when in non use. It was in relation to not wanting float charge IIRC.

[Jostalli]

Originally Posted by Davydd

I have a question about that lengthy article on lifpo batteries. The author consistently says the batteries exist best at a 50-60% SOC. What is the source for that opinion? I see the description about the "knee" chart so would assume they would live best anywhere in that range before the drop off at both ends. Does it really make a significant difference given the high cycles of lifpo batteries that I doubt most users will ever approach as the author said? Anyway, I think when on the road in a Class B it would be nearly impossible to exist around 50-60% given that driving charges rather fast. Is that just a yachting fact of life?

You already asked this. It's when stored not when in use.

[avanti]

Originally Posted by Davydd

I have a question about that lengthy article on lifpo batteries. The author consistently says the batteries exist best at a 50-60% SOC. What is the source for that opinion?

An excellent question, and one that should be asked about all the random claims that are floating around on this topic.

My suspicion is that this particular claim has its source in the following article in the infamous "Battery University":

http://batteryuniversity.com/learn/a...ased_batteries

The ultimate source is alleged to be an empirical study at "a CADEX laboratory" (CADEX being a manufacturer of battery chargers and related devices. N.B.:they are also the owners of Battery University ). There is no actual citation, although I suspect it is probably a legitimate study. However, it was done with a small sample of Lithium-Polymer cellphone-style batteries. Does the conclusion generalize to LiFePO4 chemistry? Who knows?

As far as I can see, "Who knows?" pretty much captures the state-of-the-art in this still-emerging technology. Takes time for things to settle down. In the mean time, I would recommend not taking opinion-based, anecdotal, sample-of-one "data" too seriously.

P.S. -- The above-referenced article also contains a discussion that may (or may not) be relevant to the "charge voltage" issue. If I read it correctly, the claim is that lower charge voltages significantly increase battery lifetime, but at the expense of amp hours stored. If this is true, it is a straight tradeoff, and so charge voltage a matter of taste, not of "correctness".

[Davydd]

That's my point. If I drive home and park my batteries are going to be fully charged. I don't think I can change that easily. BobB, I think explained it as a yachting fact of life. Puttering into the harbor after mostly sailing most likely will not fully charge the batteries and that's OK according to that article. My question was where did the source of his information come from? He gave none that I can remember.

The point is in an RV I doubt many will deliberately take the time to stop with a 50-60% SOC and store. And if you are driving most days you are almost always going to be at 99% SOC and good luck if you think you can control that and why would you want to reduce your amp hour capacity to the capabilities of AGM batteries? And of course what is the end game when you'll have infinitely more cycles out of your batteries that will most likely last your time of ownership regardless? Tying your hand behind your back for the next owner?

For the most part there was nothing new in that article I hadn't already read and I think my Advanced RV has it all covered. The 50-60% SOC statement just seemed strange and actually pretty contradictory to common sense at least in regard to RVs with no end game consequences of source information.

[BobB]

Originally Posted by Davydd

BobB, I think explained it as a yachting fact of life.

Davydd,

Forgot to say that whenever you return your charter sailboat (or if you pull into a marina on your travels) you always plug into shore power and flip on the switch for the battery charger. Keeping the batteries "topped" off is the usual.

Most battery usage on a charter sailboat is for navigation instruments, radio, fridge, lights, cabin fans, your computer (usually via an inverter). Rarely see anyone run a microwave and never AC, unless the boat has a generator.

"Cruising" sailboats - i.e. where owners live aboard and many cruise full-time - you see more generators, wind generators, solar, inverters and sophisticated energy management systems. It is nice to have all the comforts of home, since often the boat is home.

[eurovanman]

Davvyd needs 800ah because he spends 22 hours a day on internet forums. I for one would be perfectly happy and have more than enough energy with 200ah lithium batteries. To each their own.

[Davydd]

Originally Posted by BobB

Davydd,

Forgot to say that whenever you return your charter sailboat (or if you pull into a marina on your travels) you always plug into shore power and flip on the switch for the battery charger. Keeping the batteries "topped" off is the usual.

Most battery usage on a charter sailboat is for navigation instruments, radio, fridge, lights, cabin fans, your computer (usually via an inverter). Rarely see anyone run a microwave and never AC, unless the boat has a generator.

"Cruising" sailboats - i.e. where owners live aboard and many cruise full-time - you see more generators, wind generators, solar, inverters and sophisticated energy management systems. It is nice to have all the comforts of home, since often the boat is home.

Bob, With that explanation it makes the 50-60% comments as almost gospel all the more confusing. That then is not much different than RVing. I would still like to know what authority established that SOC comment and specifically the 50-60%. Technomadia made a similar comment I think at 80% but again with no backup authority. I can program my bottom SOC and Advanced RV programmed the minimum at 20% as opposed to Roadtrek stating 10%. I've programmed 25%. I can't program a top SOC I don't think. Advanced RV brakes it down gradually at 99% and charging stops. However the readout when my SOC percent gets down to 0% it is really 25% though I haven't hit that mark yet because I got up and drove. I have no idea if the upper SOC is really short of full. I never asked.

My only sailing experience has been one day trip on Narragansett Bay in Rhode Island, one day trip in San Diego Bay and one week in the British Virgin Island. At home on Lake Minnetonka I've always been a motorboat, canoe and kayak man.

[Davydd]

Originally Posted by eurovanman

Davvyd needs 800ah because he spends 22 hours a day on internet forums. I for one would be perfectly happy and have more than enough energy with 200ah lithium batteries. To each their own.

Aw shucks. Don't be too jealous you can't get by on 2 hours sleep like me.

[eurovanman]

Originally Posted by Davydd

Aw shucks. Don't be too jealous you can't get by on 2 hours sleep like me.

You da man.

[rectalogic]

Roadtrek posted a FAQ with more details on the system

https://www.facebook.com/groups/road...8584128967238/

[markopolo]

That's great.

I figured when he posted questions he'd get around to posting a Q & A topic.

Just give them some time and breathing room.

[booster]

Originally Posted by markopolo

That's great.

I figured when he posted questions he'd get around to posting a Q & A topic.

Just give them some time and breathing room.

Very nice start for them, I think some of the heat about proprietary has induced some more transparency, which is great. The cold protection sounds like a typical system, although he didn't mention what happens if you hit low temp and low bat cutoff at the same time. Maybe switches to engine source, maybe autostart, but hopefully they do something more than telling you to find shore power or go someplace warm.

It will be very interesting to see how they perform in practice, and it does sound like they will able to retro into older charge system units. That would indicate that they probably do internal voltage regulation as well as charge cutoffs, which would make it a true drop in except for things like bigger wiring to feed it.

It also sounded like it will not be available as a part, only as a dealer installed to non modded original Roadtreks. Big bummer on the that.

[gerrym51]

Originally Posted by booster

Very nice start for them, I think some of the heat about proprietary has induced some more transparency, which is great. The cold protection sounds like a typical system, although he didn't mention what happens if you hit low temp and low bat cutoff at the same time. Maybe switches to engine source, maybe autostart, but hopefully they do something more than telling you to find shore power or go someplace warm.

It will be very interesting to see how they perform in practice, and it does sound like they will able to retro into older charge system units. That would indicate that they probably do internal voltage regulation as well as charge cutoffs, which would make it a true drop in except for things like bigger wiring to feed it.

It also sounded like it will not be available as a part, only as a dealer installed to non modded original Roadtreks. Big bummer on the that.

my question would be this-drastically increasing battery capacity without a 2000 or up inverter gets you what?.

would the power of an e-trek{original) without an inverter to utilize it be worth it

Jim has said he can do the ecotrek batteries-but he will not do big inverter and wiring for it retrofits

[booster]

Putting the setup in an older unit without the inverter upgrade, engine generator, etc, would just get you battery capacity at lower weight, which ain't all that bad for many.

I think the 200ah setup into a "normal" 12v based Roadtrek would be a very good setup, although pretty spendy.

I don't think you will see the big packs into existing units. Maybe 400ah on a few, but not bigger.