Rockwood
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Trailer batteries
- Thread starter Bobalos
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I Have used the full rivers in my Motorhome for over 5 years with ZERO issues. My brother sells them since he has a RV dealership. yes my solar guy has taken apart lipo batteries and has showed me the BMS in his batteries take the whole top of the battery. He said the amazon ones BMS is maybe 3" square with much less electronics in them. Just passing info along from someone I trust on the subject. I am sure there are some good ones out there. chit I sure hope so.
BTW the Rolex vs timex doesn't really hold water unless your roles was on a watch winder the whole time. If you forget to wind it everyday then the time for sure will be off. Just saying. Hard to beat a Timex anyway. Rolex I would think is more Jewelry than a watch. If you know watches Rolex is not really known for Keeping great time. Like Mentioned you have to wind those watches everyday. But I do get your point Steve.
BTW the Rolex vs timex doesn't really hold water unless your roles was on a watch winder the whole time. If you forget to wind it everyday then the time for sure will be off. Just saying. Hard to beat a Timex anyway. Rolex I would think is more Jewelry than a watch. If you know watches Rolex is not really known for Keeping great time. Like Mentioned you have to wind those watches everyday. But I do get your point Steve.
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Bobalos
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I did a little digging around and I have one of the IOTA chargers (will check tonight to see which one) & I bought the dongle that monitors the battery & controls the charge to the battery.
as it turns out they have a whole mess of these dongles. Im not sure which one I have now, but Im guessing its not ideal for the dual AGM batteries I have in the trailer now. I will look into this as well, this evening.
as it turns out they have a whole mess of these dongles. Im not sure which one I have now, but Im guessing its not ideal for the dual AGM batteries I have in the trailer now. I will look into this as well, this evening.
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Bobalos
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Right now I have 2 optima 34 group batteries in my trailer. with the box that is in it, I cant fix a 200AH or larger battery in the box. I can fit the 100AH battery in it.
if Im reading it right, one of the 100AH CHINS or Ampere Time batteries will actually be more battery than the 2 Optima's. is that right?
FWIW, the battery setup I have now works fine. I normally run my genny a couple of times a day to run run the microwave & compressor and to charge up the batteries before I goto bed. I have never had an issue with the battery voltages getting low enough that the heater stops working @ night.... In fact Im guessing I could go a few days without firing up the Genny....
Also, It looks like I should buy the smart charge controller for the LiFePo4 battery type for the IOTA DLS 55 converter/charger I have. seem to make sense too?
if Im reading it right, one of the 100AH CHINS or Ampere Time batteries will actually be more battery than the 2 Optima's. is that right?
FWIW, the battery setup I have now works fine. I normally run my genny a couple of times a day to run run the microwave & compressor and to charge up the batteries before I goto bed. I have never had an issue with the battery voltages getting low enough that the heater stops working @ night.... In fact Im guessing I could go a few days without firing up the Genny....
Also, It looks like I should buy the smart charge controller for the LiFePo4 battery type for the IOTA DLS 55 converter/charger I have. seem to make sense too?
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Rockwood
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Technically, you can discharge down to 0% and they’re fine, but recommended to stay above 20% for best life. Lead acid don’t last long when discharged beyond 50%, which is how people say a 100ah LiFePo4 is equivalent to 200ah.
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Bobalos
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r3meyer
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Also an equal charge test it takes 4 hours to charge LiFePo4 vs 10 hours for a SLA. More then double the Gen run time.
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Bobalos
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So after talking with @Lord of the Dunes and reading this thread (btw, thank you folks, for your jnput) and a few other online sources about LiFePo4 batteries I pulled the trigger on one, 100 AH battery from Ampere Time.
@Lord of the Dunes, Also suggested i install this shunt, which has a Bluetooth app that will monitor the battery state.
It's only been in for a few days and for better or worse, it will not really get tested until next fall. I can't imagine it won't work fine for me, the question. Is longevity.....
The charger controller I have uses these little donglsles to control how it charges the batteries based on the type and configurationof the battery. Now that i have the LiFePo4 battery i had to buy the correct dongle. Kind of clever, if you ask me.
My only question right now is, how do I treat this battery? Do I leave the trailer plugged in all of the time and let the charger monitor the battery and take care of it, OR leave it unplugged all of the time and allow it to discharge a bit between charges? I'm a lazy ass and would love to just leave it plugged in and let the charger do its job.
@Lord of the Dunes, Also suggested i install this shunt, which has a Bluetooth app that will monitor the battery state.
It's only been in for a few days and for better or worse, it will not really get tested until next fall. I can't imagine it won't work fine for me, the question. Is longevity.....
The charger controller I have uses these little donglsles to control how it charges the batteries based on the type and configurationof the battery. Now that i have the LiFePo4 battery i had to buy the correct dongle. Kind of clever, if you ask me.
My only question right now is, how do I treat this battery? Do I leave the trailer plugged in all of the time and let the charger monitor the battery and take care of it, OR leave it unplugged all of the time and allow it to discharge a bit between charges? I'm a lazy ass and would love to just leave it plugged in and let the charger do its job.
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Bobalos
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And yes I know the battery cables look like kind of a mess, that is a project for June or July. I needed it done for right now.
Lord of the Dunes
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According to the net, LiFePo4 batteries get stressed if they spend a lot of time at 100% or 0%. Since they don't discharge very much, I'd disconnect it and let it discharge slowly until you need it again. They only self discharge a little bit every month, so even if you leave it sitting for 5 or 6 months, it will still have plenty of charge.
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Bobalos
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I can unplug the trailer and just let it sit. I've done it that way for years. Letting it drain with the few little vampires, is not a big deal. I'm in and out of the trailer once a week or so, plugging it in would be not problem.
Does your charge controller have any type of "storage mode" for lithium batteries? It would keep them roughly 50% charged. Its a very common feature on chargers used for RC planes that use lithium batteries. Im not sure if that technology is common to the RV world yet.
I do a hybrid version of the lazy method. The easy way is to turn off my battery disconnect switch and also put a switch on the solar panel if/when equipped.
If you want to add extra effort you need to look at your climate. I remove my batteries from the trailer when its 30F weather and when its 100F weather. Stick them in the garage to buffer the temp swings.
Now you can go a little more advanced and actually trick batteries. Lets say its winter and i was too lazy to remove the batteries. I will flip on the battery disconnect switch and let the batteries sit at 13.5v in that cold weather for weeks at a time. They love it. Come summertime that would be a mistake. You dont want to pump 13-14v into a battery thats stored in 100F weather. (this relates more to golf cart batteries or any 12v marine/rv battery)
My normal routine is every couple months i remember to hook up my solar using the blue wire nut. Let it sit for a couple days and take it off. Could do the same thing with the trailer disconnect switch. Although if youre still following along here is an important part. Im using golf cart batteries so i can leave the charger hooked up....get to 100%....and disconnect. Once i switch over to lithium i would purposely discharge the battery to 50% or 70% or whatever the manufacture recommends. Then disconnect the charger when the lithium battery is closer to "storage voltage". There is no real exact number. Its like LOTD said. You dont want 100% and dont want 0%. Especially in certain temp conditions. 100% charged is extra bad when the temperature is also high. That might effect your laziness methods. With summer coming i wouldnt leave it hooked up at 100% on your brand new awesome battery. I would flip on lights and actually drain it some. Which is totally backwards to what you do with flooded batteries.
It comes down to the excitement of the atoms inside the battery. You dont want them bouncing off the walls and bouncing into each other. That all equates to wear and tear. A fully charged lithium is shaking like crazy. Same with an overly hot lithium. Ideally they are stored around 60% charged and in nice low 40F temps. People with smaller lithium batteries can take advantage of this by storing batteries in the fridge. Before use let them come to room temp.
r3meyer
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Unplug your converter. Its only job is to recharge at high amps when you're actively using the trailer. You want to just use a simple trickle charger designed for these batteries. I use these on all my toys that have LiFeP04. I have 6 of them in total.
https://www.amazon.com/dp/B07W6B987F?ref=emc_p_m_5_i
r3meyer
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If the trailer is out in the sun, then I would get a solar panel and a cheap charge controller to keep it happy.
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Bobalos
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Do you keep your batteries plugged into this controller the whole off season?
Do you disconnect the batteries from the load before putting the charger on it and letting it sit for the off season?
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Bobalos
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This is the charger I have:
https://www.iotaengineering.com/products/detail/1185687/iota/dls-55a-converter-and-charger/55-amp-acdc-power-converter-and-battery-charger-for-dc-load-operation-and-12v-battery-charging
This charger allows for Dongles that control the charger for whatever battery type and configuration you have. I used to have the lead acid dongle (which was probably not right for 2 AGM's in parallel, but thats the way it was), now I have the dongle for LiFePO4 batteries.
https://www.iotaengineering.com/products/detail/1195178/iota/iq4-lifepo-smart-charge-controller/2-stage-smart-charge-controller-for-the-iota-dls-to-use-with-lithium-ion-batteries-with-bms
This is a quote from IOTA's website about the dongle for LIFePO4 batteries.
It "seems like" I should be able to "set it & forget it". Im asking because Im not familiar with this battery technology...
https://www.iotaengineering.com/products/detail/1185687/iota/dls-55a-converter-and-charger/55-amp-acdc-power-converter-and-battery-charger-for-dc-load-operation-and-12v-battery-charging
This charger allows for Dongles that control the charger for whatever battery type and configuration you have. I used to have the lead acid dongle (which was probably not right for 2 AGM's in parallel, but thats the way it was), now I have the dongle for LiFePO4 batteries.
https://www.iotaengineering.com/products/detail/1195178/iota/iq4-lifepo-smart-charge-controller/2-stage-smart-charge-controller-for-the-iota-dls-to-use-with-lithium-ion-batteries-with-bms
This is a quote from IOTA's website about the dongle for LIFePO4 batteries.
It "seems like" I should be able to "set it & forget it". Im asking because Im not familiar with this battery technology...
r3meyer
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The IOTA says it initializes a full charge if left in float state for 15 days. I would not want this.
Im sure it would be fine either way, I have just found its more economical to use the smaller NOCO chargers.
Im sure it would be fine either way, I have just found its more economical to use the smaller NOCO chargers.
Yep youre right and at least you noticed. Its a very small different. Flooded lead acid batteries like a slightly higher voltage than AGM. So if you use that dongle during the summer time the AGMs were probably not the happiest of campers.
Trying to think of the most simple way to explain this. Break it down into 2 scenarios.
1. Can you set it and forget it a couple days before a camping trip? Yes. The dongle will keep the battery fully charged and ready to go.
2. Can you set it and forget it while you store for months? Nope. You dont want to keep your LiFepo4 stored fully charged if you can help it.
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So whats the answer? I would use that cool little bluetooth shunt to determine when your battery is around 60%. Then turn off the charger. Couple days before a trip turn the charger back on. (of course monitor voltage.....make sure a small draw doesnt drain you dry)
