Travato LiFePO4 Battery Install

[ptourin]

I'd say Stark is on the edge with that advertising - they're certainly trying to give the impression that there's an active communication system between batteries and charger, implying that the battery sends a "low voltage signal" so the charger "knows when to start". But PD hasn't been at all deceptive - they were very clear with me about exactly how the chargers work.

[booster]

Originally Posted by wincrasher

Well I don't agree that Progressive Dynamics is purporting their charger to be anything more than it is. If you look at their flyer and manuals, it works exactly as they've indicated. That is now corroborated by their own tech and by two of the battery manufacturers and thru testing by myself and pturin.

By the very nature of how these LiFePo4 batteries seem to work, a sophisticated "high tech" charger is just not needed. A simple charger will suffice. The only thing really to discern them is if an absolute shut-off is needed. There seems to be disagreement on this, so buyer beware. The honesty in the PD offering is that the price reflects what they are supplying. If it was a $600 charger, I'd have a different opinion.

As far as what Stark is posting, their statements were vague enough to illicit a call for clarification. I don't see any deception here. Bad wording maybe, that needs clarification on their site.

Nobody said that PD was deceptive in anything-their literature is pretty clear on it. Stark is the one who has the deceptive specs and claimed for a PD charger, so it is their problem not PDs.

Also, nobody said that you needed any more than you said, a CC/CV charger, only most would say it does need a shutoff for lithium. There are only a few battery companies that say otherwise, and they are the ones selling batteries as "drop ins" to existing systems so you have to consider that. Stark wants you to believe that is what they are selling, when they are not.

IMO, the Stark claims are obviously, intentionally, deceptive, if not outright false, by choice. If they had just said the charger quits charging when the batteries were full, it would be like the misworded PD claim that is similar, but Stark went on to say there was a low voltage signal from the battery to restart the charger, which is totally false and intentionally trying to sell the charger as something it is not. you don't do that by accident, IMO.

Of course, everyone gets to have their own opinion.

[ptourin]

Well you put it right out there more than I did - but I'm new to this forum <lol>...
I agree about PD, and I agree about Stark - the phrase "smart charger" is Stark's, not PD's - and they use it ambiguously to imply that the chargers shut off (i.e. disconnect) from the battery, which they don't. And the low voltage verbiage can't be simply poor ad writing - I agree that it's deliberately misleading. OTOH, their engineer was very clear about how the chargers worked.

I still don't have a good scheme for tying the Victron monitor into an auto switching setup. The bistable relay doesn't help me - I can't see how I'd use it with the Victron's internal relay. And that relay can only handle 1A max @60VDC max. Still thinking and throwing the breaker manually.

[booster]

I think you may be able to find a solid state relay that takes very low current to operate. They don't switch a whole bunch of current, but should be able to do more than the output from the Victron, and hopefully be enough to activate a coil a larger capacity relay.

There is also another possibility that MIGHT work. Blue Sea makes what the call ACR relays, or automatic charge relays. They work like separators. Almost all of them have what they call start isolation on them, so they can be opened during engine starting. The interrupt is a very low current 12v signal applied to an input on the ACR. They also use this input to separate banks with a signal from their multibank charger, which how I know of them.

https://www.bluesea.com/products/761...12_24V_DC_120A

I am sure the engineers and techs at Stark are as put off by the marketing guys as we are!

[ptourin]

I just had an interesting talk with one of the guys at Advanced RV. They used to build with SmartBattery's, but have moved to building their own 100AH battery units with a much more sophisticated BMS. He said they had to replace a lot of batteries, though mostly because they weren't initially told that you couldn't charge in low temps - SmartBattery now says "operate above -4 degrees F", though they list performance capacities (that is, discharge cap's) way below -4. But he said they were having troubles below freezing - he talked about temps in the 10-20 F range. He also said that they have heater packs in their battery area now.

He said that they'd discovered how little battery management the old batteries have. Though he didn't have too much to say about damaging batteries via overcharging, he did say they assumed that if you left the charger continuously online there was the possibility of battery damage.

I believe they're now using a total coach monitor from Silver Leaf Electronics in the RV's - Total Coach | SilverLeaf Electronics, Inc. - and he says they've developed much more sophisitcated monitoring capabilities in the current units.

They're also using a 2nd alternator for coach charging, and actively exploring different choices in this area. I asked him about the issue of damaging Sprinter engines by running them at high idle for long periods. He said that you get different answers from different people at M-B, but that some of their higher-ups in the technical area say that it's not a problem, and mentioned refrigeration vans, which often are left high-idling for long periods.

All in all, a very interesting few minutes - I felt he was very generous with his time in answering questions from a random caller.

[ptourin]

Hey Wincrasher, I just saw that SmartBattery has your blog up on their website - nice!
Have you found out anything more about the overcharging issue with the PD charger? I've been busy lately and haven't called SmartBattery back to try to pry more info out of them. I'm still not running my charger full time either, and I haven't gone any further with trying to build a system that automatically switches the charger in and out.

I did notice that their website and their video now do specifically say that their internal control board does cell balancing - or, I suspect it's really bank balancing. I suspect that's in response to a lot of phone calls from people like me, asking, "What you don't have ANY cell balancing?" <g>... You may remember that on one of my calls to them, one of their support guys told me that there was no cell balancing provided or needed because of their careful cell matching at the factory - but tucked way down on one of their pages there was a comment that they balance banks by providing up to 2A to the lowest bank.

[wincrasher]

Well, I'm not exactly thrilled that they linked to my blog without asking or remuneration.

Like you, I have not left mine on the charger while in storage. I've thought about just installing a switch so I can turn the converter/charger on and off manually. I believe with it off, the house would still have 12v power to all the systems via the battery.

Since I posted last, I've ordered a new van - a 59K with a 2 battery setup. I believe I can transfer my lithium charger and get a second battery and have a similar setup in that van. I may wait until Zamp comes out with their upgraded solar controller (for lithium) to do this project.

[ptourin]

Oops, that wasn't too smooth of them! They also offered me a discount on the batteries if I discussed them in forums and blogs, but then didn't give it to me - though I did wait quite a while after the offer before actually ordering.

I'm doing the same - I had a 120v breaker that powered the charger and fridge - I relocated the fridge wiring, so now I can simply throw the breaker to turn the charger off. IIRC, at the moment my battery monitor alarm goes off at 50% SOC, so there's lots of time to get to turning the charger on.

I sure wish I could resolve the question of overcharging damage, but it doesn't seem too easy to get there. I'm not sure I understand the problem. If the charger goes down to 0 amps, and if the bank balancing always brings the lowest bank up, I'd think that for a while there'd always be a lowest bank and therefore some current draw from the charger, but as the difference between the present lowest bank and the other banks gets smaller, the charge current would get closer and closer to zero, and at the point that they all match, there'd be no charging current draw. I'd think that the problem would only appear if balancing doesn't work, so the charger keeps supplying current trying to charge the lowest bank while overcharging the rest. But I'm not at all sure I understand this. Maybe Booster will chime in on this one...

[ptourin]

I finally reached a support engineer at SmartBattery today, and I'll put down what he said - with a big caveat at the end...

I asked about charging - specifically, charging their batteries with Progressive Dynamics lithium chargers, which are CCCV chargers that charge to 14.6 volts. I asked whether the charger could be left connected 24/7 without damaging the batteries from overcharging - the question that people on various forums are asking. His answer was that I could - that the charger would ramp up to 14.6v and the current would go down towards zero. He said that 14.6 volts would not overcharge the batteries, and in any event they have an internal over/under voltage relay that would open if the voltage got up to 16v. To me, that's a "party line" sort of statement - I consider a 16v relay opening more like disaster prevention than real battery management. I asked about the issue of small imbalances between banks allowing the better banks to overcharge while the charger tried to bring the weakest bank up to 100% SOC. He said it's not an issue with SmartBattery because the battery cells are so well matched at the factory that they're almost perfectly balanced, and they remain so - very little current drawn as the battery as a whole approaches 100% SOC. That's what he said...

That led to a discussion of balancing circuitry - their website is not clear about whether they have top balancing circuitry or not. He said their BMS doesn't have any balancing functionality, that their manufacturing process matches all cells, and therefore all banks, well enough so it's not needed. That's what he said...

Now it gets a bit less clear - I asked him about the temperature/performance data on their website. He said that the graph of temperature vs. usable capacity referred to ambient temp, but he waffled a lot about whether it was ambient or battery temp - he finally chose ambient, and pointed out that in cold weather the battery temp is always going to be the same or higher than the ambient temp (I was asking about low temp issues, as their high temp end doesn't worry me as much). So he said that I can discharge way down below zero F or even -20F without damaging the batteries as long as I understand how the low temp will affect usable capacity. He also pointed out that their internal BMS has low voltage disconnect as well as overvoltage, so the battery will disconnect if it drops below 8v. He pointed out that in winter outside storage, you simply charge the battery to near 100% before storage and you disconnect it - since they don't self-discharge much when disconnected, they can sit all winter with no damage and lose a lot of capacity - and I believe that from everything I've read.

Then I asked him what their "Operating Temp. -4F to +175F" meant. He said that it meant that although I could discharge below -4F, I shouldn't charge below that temp. I asked him several times whether he was sure that I could safely charge below freezing, and he said yes. He pointed out that in almost all RV use, the temp is well above -4F when you'd be charging - and that's certainly true for me. Maybe not if it were a car, but it's an RV. That's what he said...

I do need to add a caveat here. I didn't get the sense that I was talking to an engineer, not even a Tier 1 support engineer type - he sounded more like a battery technician. At first he wanted to convince me that I hadn't paid attention to their specs, and he pushed pretty hard trying to get me to say I hadn't studied the data on their website - he was a bit condescending at first. I pushed back pretty hard on this, saying that the data was incomplete and in places very unclear, and that's why I was on the phone. In the process I found that he could quote what was on the site quite well, but that he was pretty unsure when I pressed for detailed info. So I'm still not sure how much more I know than before I called. As I said before, Caveat Emptor! I've taken the plunge - we'll see if I burn, freeze or come out OK <g>...

[gerrym51]

Originally Posted by ptourin

I just had an interesting talk with one of the guys at Advanced RV. They used to build with SmartBattery's, but have moved to building their own 100AH battery units with a much more sophisticated BMS. He said they had to replace a lot of batteries, though mostly because they weren't initially told that you couldn't charge in low temps - SmartBattery now says "operate above -4 degrees F", though they list performance capacities (that is, discharge cap's) way below -4. But he said they were having troubles below freezing - he talked about temps in the 10-20 F range. He also said that they have heater packs in their battery area now.

He said that they'd discovered how little battery management the old batteries have. Though he didn't have too much to say about damaging batteries via overcharging, he did say they assumed that if you left the charger continuously online there was the possibility of battery damage.

I believe they're now using a total coach monitor from Silver Leaf Electronics in the RV's - Total Coach | SilverLeaf Electronics, Inc. - and he says they've developed much more sophisitcated monitoring capabilities in the current units.

They're also using a 2nd alternator for coach charging, and actively exploring different choices in this area. I asked him about the issue of damaging Sprinter engines by running them at high idle for long periods. He said that you get different answers from different people at M-B, but that some of their higher-ups in the technical area say that it's not a problem, and mentioned refrigeration vans, which often are left high-idling for long periods.

All in all, a very interesting few minutes - I felt he was very generous with his time in answering questions from a random caller.

have you read Davydds posts about Alvar his ARV sprinter van. he has all the stuff you describe

[ptourin]

Thanks - I hadn't see that thread. I've been reading it for hours and I'm only up to pg 21 of over 70 - the suspense is killing me...

[gerrym51]

Originally Posted by ptourin

Thanks - I hadn't see that thread. I've been reading it for hours and I'm only up to pg 21 of over 70 - the suspense is killing me...

at least you can get thru it in a reasonable period of time-we had to keep listening to him over a long time period-Uh Oh -if he see's this i can expect a tart comment-lol

[ptourin]

Virtual slug-fest coming on...

[Davydd]

Nah but is like taking a fine single malt whisky than Kool-Aid.

[gerrym51]

Originally Posted by Davydd

Nah but is like taking a fine single malt whisky than Kool-Aid.

Tart-and to the point-lol

[eric1514]

When it says on the Stark website

"This is a drop in replacement for your Lead-acid battery and will require no change to your existing system."

why would someone change the charger that came with their coach originally, a PD9245, in my case?

[wincrasher]

Because they also say you need a 14.6 volt constant charge. The information is conflicting in an RV type situation.

If you were just dropping it into a boat or truck for engine starting, then the alternator charging at 14.4 to 14.6 volts would be just fine.

It's using it as a house battery with a dedicated charger that could be an issue.

[booster]

Originally Posted by eric1514

When it says on the Stark website

"This is a drop in replacement for your Lead-acid battery and will require no change to your existing system."

why would someone change the charger that came with their coach originally, a PD9245, in my case?

Stark seems to be doing similar to Smartbattery in marketing as a drop in for lead acid, even though it does not address some of the lithium issues, like cold weather charging, not applying charge voltage once full, correct charge voltage, etc. Will it work, at least for a while? Probably. Is it anywhere near optimal? Highly unlikely. IMO, of course

[eric1514]

Those "lithium issues", like cold weather charging, not applying charge voltage once full, correct charge voltage, etc. Could a properly implemented BMS deal with them and allow for a real drop in?
Just curious.

[booster]

Originally Posted by eric1514

Those "lithium issues", like cold weather charging, not applying charge voltage once full, correct charge voltage, etc. Could a properly implemented BMS deal with them and allow for a real drop in?
Just curious.

A lot of it could be done with the BMS, but I think it would also need a remote info panel if they did, so you would know what was going on. The BMS could prevent cold charging, but not heat to allow it. It could also do cutoff of charging when the batteries were full, but it would also have to shut off most charging sources because they would most likely go high in voltage without battery reference, and they might fry electronics. It could be handled with a number of relays controlled by the BMS.

It would probably be possible, but tough, to make it a true "drop in".