Battery good news/bad news - would like advice

[Capt. Bill]

Take it from a veteran coach owner- 6 units since 1972- go with Lifeline AGM's & you'll be a 'Happy Camper'! In my 2005 MADP I replaced the cheap Newmar OEM batteries with Lifeline AGM's & they were still going strong after 9 years when I sold it to buy my 2014 MADP!. I replaced the Discover- made in China pieces of junk with 8 Lifeline AGM's -GPL 6 CT- higher height & price than OEM & 600 amp hr each & they are still doing great after 7 years!

Happy Trails

[ptw]

I agree with Capt. Bill on the Lifeline AGMs. My "Discover AGM made in China pieces of junk" are still working after 5 years. I try never to go below 50% state of charge and keep them plugged in when the coach is in storage. Letting the batteries completely discharge causes irreversible damage to the plates. This may have been what happened with your coach, and may be the reason Newmar doesn't cover them.

[astrnmrtom]

FLA batteries have a water level indicator built into the fill hole. It doesn't show water level per se, but it does indicate when you've filled the cell to the proper level, If you look down into the fill hole you'll see plastic sides of the hole that extend down a little ways. When you fill to the proper level, the water touches the bottom of this piece and surface tension makes the water surface look a little concave. Think of it as a full eye.

If you are getting only three years out of a set of flooded batteries you are doing something wrong. Lightly used and properly maintained FLA batteries should go 5-8 years.

Two ways to kill FLA batteries is letting the plates get dry especially when charging, and leaving them deeply discharged for too long especially in freezing weather. A third common mistake people make is putting them on a charger for a while, then immediately checking the voltage. This will only show what's called a surface charge, not the actual state of charge. This leads to batteries being left only partly charged.

The absolute best way to know state of charge is with a hydrometer, testing each cell after it's rested a while. Another way you can kill a flooded cell battery is topping it off with tap water. Some places with low mineral content can get away with it, but other places with high alkali water cannot.

There's lots of good reading here: https://batteryuniversity.com/

If left connected in the rig unattended for any length of time, parasitic loads will discharge them. This can happen in as little as a couple weeks or even less. I'd be willing to be this happens a lot to rigs sitting on dealer lots. The factory battery disconnects frequently don't really completely disconnect the batteries from all loads. If your rig sat on a dealer lot for a long time with discharged batteries, especially when the weather was below freezing, that's a great way to shorten a battery's life.

[Rewarder1]

If you would like to talk about lithium. Email me your number. I have a 2019 baystar that I have changed over. mccombjim3@gmail.com

[Mike8253]

Originally Posted by southardrv

Thanks for everyone's comments. I thought I'd post where we decided to go. Primarily based on people's comments that battery life should be 5+ years, I decided to stay with flooded. My main thinking about going with lithium was because in my expected ownership I'd be expecting to replace them again if they only lasted three years -- going to lithium and getting other benefits seemed more reasonable. But if it's only once, then the formula changes a bit. Since these are the first time I've ever dealt with flooded batteries, there's the possibility that I didn't maintain them properly, and that contributed to an early failure. Specifically, when I was checking the batteries' water level, which I did regularly, I always made sure that the water level was over the plates, and it was. And, since the battery issue was identified, I've seen that the procedure seems to be to make sure that the water should be at leave above the plates before you attempt to charge but, once they're fully charged, the water should be added almost to the top. I actually never had to add water, and in hindsight that may indicate that I missed that second step. So I'll give the flooded batteries another try.



Additionally, as I looked into the issue, I'd also need to get a DC/DC converter, to limit the draw of the lithium batteries from the alternator. My coach has the B.I.R.D system, which has nice benefits, but seems to complicate the installation of the DC/DC converter a bit. I could easily add the DC/DC converter between the BIRD relay and the house batteries, but then it seems like I'd be losing the ability for the chassis batteries to get charged when plugged in or the generator is running (it seems like the DC/DC converters are one-way). I expect this is solvable (probably by putting the DC/DC converter between the alternator and the BIRD relay), but given the above it's not worth it to me to try now.



So now I get the chance to try to find those flooded batteries at the Costcos round me, which may turn into a challenge. Apparently they're now in short supply -- the closest one got a shipment of 30 the day I went there and they were all gone by the time I checked (around 1:00).



And if I want to get that weight savings that I would have got from lithium, I guess I'll just have to watch the chocolate consumption this coming holiday season.



Thanks again for the advice.

I think you made the right choice for the way you camp and your anticipated ownership horizon. One thing you should definitely do is buy and install a watering system for your new batteries. Will make it so much easier to assure your water level is always where it should be. Safe travels.

[pasdad1]

Don’t go with flooded! Go with Lifeline AGM. NEVER need to check water. If you go with flooded, and for some reason a cell gets too low on water, you may be replacing them before 5 years.

[Persistent]

"To be honest, I suspect that the batteries were bad to start with. The voltages always seemed a bit low, even when fully charged, both by the actual voltage number and that the indicator on the battery status screen, that goes from left to right from empty to full, always had a 2-3 notches unmarked, as if the batteries weren't fully charged."

Indeed this would be a bad sign up front. Of course you know it takes 14 to 18 hours to fully charge a lead acid battery. The batteries could be brought up above 80% in 4 hours or so. Not fully charging after a few days starts to develop larger sulfate crystals. They tend to be problematic for long life.


"Battleborn does have a version of the battery with heating built in, for another $75 or so per battery. I'm currently leaning against that, though, at least for this coach."

The proposed system will most likely need a B to B charger between the lithium and the engine alternator. Current must be limited.

Battleborns can and will draw extremely chargin high amps. Check the battery specs.

A 100 amp hour Battle Born would draw 100 amps if it is rated at 1C. 4 batteries would draw 400 amps. The GC battery form factor batteries probably draw a lot more and I can't remember if the charging spec is 1C or 5C. This will be way too much for almost all engine alternators.

[twinboat]

Originally Posted by southardrv

I expect this is solvable (probably by putting the DC/DC converter between the alternator and the BIRD relay), but given the above it's not worth it to me to try now.





Thanks again for the advice.

The alternator output goes directly to the chassis battery. The BIRD relay has chassis and house cables on it. No alternator feed.

If you put a DC/ DC converter on the alternator output, it wil starve the chassis battery which is powering the chassis loads while on the road.

[southardrv]

Originally Posted by pasdad1

Don’t go with flooded! Go with Lifeline AGM. NEVER need to check water. If you go with flooded, and for some reason a cell gets too low on water, you may be replacing them before 5 years.

I hear you, and initially that was my thought. But some of the comments here convinced me to go with flooded. Basically, the AGM batteries were 2x or more the cost of flooded, and approach the cost of cheap lithium. So if I were to go to AGM, the marginal cost of cheap lithium would definitely be worth it, from weight savings alone (this is a gas coach, batteries are up front, and I'm close to the front axel weight limit). There just didn't seem to be a case where AGM made sense.

So going with flooded is me purchasing an option to learn a bit more about flooded, and see if they'll last as long as I have the coach, which I now expect. If I'm wrong, then I'm out a relatively little amount of money, but if I'm right, I save quite a bit of money. It just wasn't that hard for me to check the water level every now and then -- and hopefully now I know more about doing so.

[southardrv]

Originally Posted by twinboat

The alternator output goes directly to the chassis battery. The BIRD relay has chassis and house cables on it. No alternator feed.

If you put a DC/ DC converter on the alternator output, it wil starve the chassis battery which is powering the chassis loads while on the road.

Hmm...I suspected that would be a problem. I couldn't check the wiring to be sure, since the coach is currently in the shop with my end-of-first-year warranty ticket list.

If that's the case, then, where can you put a DC/DC converter to limit the current draw (if I did go to lithium)? If I put it between the chassis battery and the BIRD relay (not the BIRD device itself, but the relay that the BIRD is controlling), or between the BIRD relay and the house batteries, then it seems like that would eliminate the ability for the house charger to charge the chassis battery, as well as the ability use the BIRD to connect the house and chassis batteries to start the chassis if the chassis battery ever gets too low. Aren't the DC/DC converters basically one-way flows? If so, that would effectively eliminate the Bi-directional (the B in BIRD) abilities of the BIRD, no matter where I put it.

Do you end up with two DC/DC converters between the chassis battery and the BIRD relay, one with the chassis battery as input and the BIRD relay as output, and the other with the BIRD relay as input and the chassis battery as output? Somehow that seems like it would not work well, either.

[southardrv]

Originally Posted by Persistent

"Battleborn does have a version of the battery with heating built in, for another $75 or so per battery. I'm currently leaning against that, though, at least for this coach."

The proposed system will most likely need a B to B charger between the lithium and the engine alternator. Current must be limited.

Battleborns can and will draw extremely chargin high amps. Check the battery specs.

A 100 amp hour Battle Born would draw 100 amps if it is rated at 1C. 4 batteries would draw 400 amps. The GC battery form factor batteries probably draw a lot more and I can't remember if the charging spec is 1C or 5C. This will be way too much for almost all engine alternators.

Definitely -- they're rated at .5c, so a 6-battery bank would be drawing 300 amps. Not only would the alternator be in trouble, but I'd be concerned about the cable gauge being way too small and the resulting fire danger (but I can't check on my actual coach -- it's in the shop now).

I'm still trying to figure out the circuit diagram that would work with a DC/DC converter to limit the current and still preserve the bi-directional capabilities of the BIRD. At this point, though, it's mainly a thought experiment, since I'll be going with flooded batteries for this time....if they fail again, though....

[RandDescape]

Since you have brand new flooded batteries this is the time to invest in a good battery watering system. I installed the Flow-rite (Amazon) which isn’t cheap but makes the monthly add of water in my 8 FLA batteries take about 5min including the unlock of the bay; getting the distilled water; actually filling the batteries; and putting everything away.

A good system takes all the guess work out and makes it easy to fill every cell correctly no matter the weather.

- Richard

[Tigerfan1]

Originally Posted by Winemaker2

Agree strongly.
I'm not a Li user so will resist detailed comments but you asked about economical alternatives and at least IMO Li is not economical unless you are looking at a LOT longer than 5 yrs.
Eliminating your 2 "up front" battys not easy or realistic as I'm guessing they are for chassis while the others are house battys... very different and should be considered.
IMO AGMs are an excellent no/lo maint choice if you are not considering this your long term MH choice.
I've have 3 East Penn / Duracell AGMs that have served 8 seasons and still going strong. Sams Club sells EP / Duracell at hard to beat prices if you are looking for economical solutions and considering moving away from FLA.

Same here with the Dura Cell AGM. Good economical choice.

[Winemaker2]

Originally Posted by RandDescape

Since you have brand new flooded batteries this is the time to invest in a good battery watering system. I installed the Flow-rite (Amazon) which isn’t cheap but makes the monthly add of water in my 8 FLA batteries take about 5min including the unlock of the bay; getting the distilled water; actually filling the batteries; and putting everything away.

A good system takes all the guess work out and makes it easy to fill every cell correctly no matter the weather.

- Richard

When you add $25 - $50 per batty for a watering system it makes AGM less of a premium to get even lower maint and eliminate corrosion.