RV Batteries

[Guest]

Brian,

I cannot find the link I once observed but the Dragonfly was cheaper when I had seen it. There is also an article out there where DragonFly will supply batteries for Keystone 5th wheels but I looked on the Keystone site and did not find any mention of that. So maybe today the DragonFly is for the RV industry and the Battleborn is for consumer purchase? The three year warranty on the DragonFly is still a mystery.

Jim

[Guest]

Brian,

I see the $999.00 verbiage on their site. But with a three year warrantee? I could have used your IT expertise since this past week, I spent two days at home while my work PC was being rebuilt since Window 10 would not install.

Jim

[Guest]

Here is a site where the dragonfly battery can be purchased for $999.00

https://www.cascadiavans.com/product...y-100-amp-hour

Jim

[Guest]

Trojan has some very nice features such as CAN communication to integrate with devices that would consume those signals. Their cycle life looks to be excellent based on DOD and they also show (what others do not) how the charge current should be adjusted based on temperature. This is done in the auto industry to maximize battery life on EVs. However, this can easily be overcome by simply keeping the battery conditioned by locating it inside the Rig or by using a heating blanket made for batteries such as the battleborn unit. It would be so nice if a battery could be programmed to have user selectable DOD and SOC to maximize battery life even further.

[RickLight]

I just went for Lion Energy UT 1300. A local dealer has them for 750, and ran an even better deal at a show.

Will Prouse did say some nice things about them. And some not good things on an earlier version, capacity issues. Trusting the brand was a hard call for me.

Now to rewire the 12V mains...

[Guest]

Received the Victron BMV712 Smart with Battery temperature sensor. Nice feature on this unit is that it can be mounted in the passthrough since its blue tooth for cell phone viewing of parameters. Thinking since this will give me high/low battery limits, I'm curious if it could be configured to interface with Victron's battery protect device. Howard would you or others know?

Since the Progressive Dynamics unit will operate the rig without a battery, I'm planning on installing a marine switch to turn off the battery while plugged into an AC pedestal. Thinking of utilizing all four terminals on the charger and run cables from the battery to the switch then on to the charger in the passthrough and from the charger to the busbars on the frame. This will allow me to disconnect the battery when AC power is on where I would turn on the marine switch for battery charging and running the rig on DC only. Or when traveling.

https://www.amazon.com/Victron-BMV-7...79529220&psc=1

[Guest]

I just went for Lion Energy UT 1300. A local dealer has them for 750, and ran an even better deal at a show.

Will Prouse did say some nice things about them. And some not good things on an earlier version, capacity issues. Trusting the brand was a hard call for me.

Now to rewire the 12V mains...

Rick,

The new Lion Energy looks to be nice.

I have seen his tear downs. Will is extremely bright but some of his battery advice may not fit everyone's needs. For instance, the Valence battery is the highest quality of any brand but its not recommended due to lower capacity? Two of these batteries would work perfectly for my Imagine. The other is some companies do not build in a low temperature disconnect for a reason. There is nothing wrong with drawing current from a Lithium battery at below freezing, so some may not want to have a forced shutdown and would rather take measures as to not have excessive charge rates at low temperatures. IMO I do not want to rely on the BMS as the main protection device but rather as a redundant one. It would be nice if Will would explain that Lithium batteries need different charge rates at various temperatures to extend battery life, where battery damage does not occur right at 32F if being hit with an excessively high charge. Charger manufacturers really need to build a truly smart charger that takes temperature into account. Thought I had this will the AIMS but the fan on all the time was a deal breaker.

Jim

[bertschb]

...The other is some companies do not build in a low temperature disconnect for a reason...

Jim

Just curious why a company would do this. My understanding is a low temp disconnect is necessary to protect LiFePO4 batteries from being damaged from charging when the temp drops below freezing. That's why Will doesn't recommend batteries (or a BMS) that doesn't have low temp disconnect.

BTW, I'm planning to order two batteries in the next week or so before our new 310GK-R arrives. Still not sure what I'm going to get. The dealer said he will give me a credit for the two LA batteries they were going to install. Not sure how much the credit is yet. He said it might be $100ea.

-Brian

[bertschb]

Dragonfly Energy (parent company of Battleborn) announces new 250ah GC3 battery will be factory installed in some RV's. I'm going to do some digging to see if this battery is available to consumers and if so, how much it costs.
https://rv-pro.com/news/new-dragonfl...-montana-fiver

[Yoda]

Not everyone can afford Li-ion battery or make the changes to use them. Which brings up a question. If I do go Li-ion battery what changes do I need to make as I have a solar package tied to 2 12V in parallel. Deep cycle Interstate brand from dealer. In other words what would it take to set up a basic Li-ion battery set up and possibly why for those like me that only know a bit about Li-ion battery's from the battery packs I use in my tools. They run great right up to the end of the charge.

Second question - for folks using led-acid what is the best set up. I have used 2 Trogen golf cart battery's in series tied to the trailer stock 12v in parallel with good success, but did not understand the issues of doing that. My goal was to run 4 Trojan golf cart units, but weight up front is an issue. Thoughts on this

Keith

[bertschb]

...In other words what would it take to set up a basic Li-ion battery set up and possibly why for those like me that only know a bit about Li-ion battery's from the battery packs I use in my tools.

Hi Keith

You can actually just do a straight drop in replacement of your L/A batteries with LiFePO4 batteries. BUT, a standard (non Lithium) converter/charger won't fully charge LiFePO4 batteries. Standard converter/chargers won't charge at 14.6v and will switch to trickle charging when the battery approaches a full charge and basically just sit there. A converter/charger with the capability to charge both L/A and Lithium batteries is capable of charging LiFePO4 batteries at "full speed" right up until they are full so your batteries get recharged more quickly and more completely. A popular converter/charger that is used for LiFePO4 batteries to replace the factory WFCO converter/charger is the Progressive Dynamics PD9160ALV.

There are several reasons to switch to LiFePO4 from lead acid. LiFePO4 batteries are lighter. They charge much faster (with the proper charger). You can use 100% of the stated capacity. With a lead acid battery, you can only use about 50% of the stated capacity. So, a single 100ah LiFePO4 battery has roughly the same capacity as two 100ah lead acid batteries. Another advantage is LiFePO4 batteries can be cycled several thousand times before capacity drops. Probably 5-10 times as many cycles as a lead acid battery. LiFePO4 batteries also come with a Battery Management System (BMS) that protects the batteries from being over and under charged (among other things). Another advantage with LiFePO4 is you don't need to vent the battery compartment or add water. You can also mount them sideways, upside down, etc.

The only real downside is the upfront cost but over time, the cost ends up being closer to lead acid.

Having said all of this - I am NOT an expert on batteries at all. I am pretty good about reading up on them though :-) I plan to buy some LiFePO4 batteries and a replacement converter/charger in the next week or two. At least then I'll have some real world experience so my comments will carry a teeny more weight. I'll let the real experts chime in now!

-Brian

[Yoda]

Hi Keith

You can actually just do a straight drop in replacement of your L/A batteries with LiFePO4 batteries. BUT, a standard (non Lithium) converter/charger won't fully charge LiFePO4 batteries. Standard converter/chargers won't charge at 14.6v and will switch to trickle charging when the battery approaches a full charge and basically just sit there. A converter/charger with the capability to charge both L/A and Lithium batteries is capable of charging LiFePO4 batteries at "full speed" right up until they are full so your batteries get recharged more quickly and more completely. A popular converter/charger that is used for LiFePO4 batteries to replace the factory WFCO converter/charger is the Progressive Dynamics PD9160ALV.

There are several reasons to switch to LiFePO4 from lead acid. LiFePO4 batteries are lighter. They charge much faster (with the proper charger). You can use 100% of the stated capacity. With a lead acid battery, you can only use about 50% of the stated capacity. So, a single 100ah LiFePO4 battery has roughly the same capacity as two 100ah lead acid batteries. Another advantage is LiFePO4 batteries can be cycled several thousand times before capacity drops. Probably 5-10 times as many cycles as a lead acid battery. LiFePO4 batteries also come with a Battery Management System (BMS) that protects the batteries from being over and under charged (among other things). Another advantage with LiFePO4 is you don't need to vent the battery compartment or add water. You can also mount them sideways, upside down, etc.

The only real downside is the upfront cost but over time, the cost ends up being closer to lead acid.

Having said all of this - I am NOT an expert on batteries at all. I am pretty good about reading up on them though :-) I plan to buy some LiFePO4 batteries and a replacement converter/charger in the next week or two. At least then I'll have some real world experience so my comments will carry a teeny more weight. I'll let the real experts chime in now!

-Brian

Brian - this is dangerous. Your right up there withe the original Rob Cate&Rob in costing me money. I actually understood your thinking (great response) and when the time comes I will give it serious thought. One more thing for the round-to-it list. Ill haft to read up too.
Thanks

[gbkims]

Nothing to add as far as batteries. This dwg is how I've wired mine so far.

[Guest]

Jim

Just curious why a company would do this. My understanding is a low temp disconnect is necessary to protect LiFePO4 batteries from being damaged from charging when the temp drops below freezing. That's why Will doesn't recommend batteries (or a BMS) that doesn't have low temp disconnect.

BTW, I'm planning to order two batteries in the next week or so before our new 310GK-R arrives. Still not sure what I'm going to get. The dealer said he will give me a credit for the two LA batteries they were going to install. Not sure how much the credit is yet. He said it might be $100ea.

-Brian

Brian,

I believe some do not do this so folks can still draw current but make sure they pay attention to the charging. I like what Trojan did with listing charge limits versus temperature. This shows the charge rate needs to be adjusted at different temperatures and not just shut the battery down. I personally like the Trojan and feel they are the most straight forward in their claims.

The best way to mitigate charging issues at cold temperatures is to heat the battery or have it inside in a heated passthrough or in the cabin.

IT did a number on my work PC Brian. Can only stay logged in for 2 minutes at a time. Lol

I've switched to another unit.



Jim

[bertschb]

You can draw below freezing, it's just not good to charge below freezing. A good BMS won't allow charging when temps drop below freezing.