"That's Very Smart"
Skip to main content

Topic: Dragonfly Lithium batteries not holding charge (Read 380 times) previous topic - next topic

0 Members and 1 Guest are viewing this topic.

Dragonfly Lithium batteries not holding charge

I just bought a 2022 UnityFX and we are pretty new to this.  Stayed three nights at a campground with no hookups so made sure batteries were charged up with Generator and only had furnace on, batteries discharged in 3 hours.  We have 400w factory solar, (2) Dragonfly DFGC2H 100ah LiFePO4 batteries, factory 2k watt inverter and an Onan 3200 diesel gen.  Any suggestions on how I can tell if the batteries are bad or I may be doing something wrong, would be helpful

Re: Dragonfly Lithium batteries not holding charge

Reply #1
I have a similar setup with 200 watt factory, 2, 100-amp Battleborn batteries, and a similar generator on a 2020 Unity.  Unfortunately, I am learning as well, having picked her up early this summer.  That said, my first thought is what happens at home when you are unplugged?  Does it drain off then? If yes, try to see what is draining by seeing what happens with the inverter off.  At least that will tell you whether the drain is mainly AC or DC.  I would also look to make sure the refrigerator was not on DC mode instead of propane-mode. 

Re: Dragonfly Lithium batteries not holding charge

Reply #2
I strongly suggest you buy a Victron SmartShunt for $100.30 from Amazon and then you will be able to accurately see what is going on...once you set it up properly.  It would be very  unusual for the Dragonflies to die this soon in their life.

When you think you are full, are you really?  When you think everything is off, is it really?

The Smartshunt will show you what is really going on.  How much charge is going into the batteries?  How much current is coming out.  The Smartshunt is worth its weight in gold to let you see what is really happening to your batteries, and there is NOTHING that comes on the coach that gives you a good report on your bacttery activity.

That said,I wonder if you have your refrigerator on 12 volts.  That will take around 15A out each hour.
Brad
2021 Wonder RL

Re: Dragonfly Lithium batteries not holding charge

Reply #3
A SmartShunt is a great suggestion, this will help greatly with monitoring your Lithium battery state. The smart shunt connects through the VictronConnect phone app and displays battery percentage, amps displayed as positive represent charge, amps displayed as negative represent draw, estimation of how long batteries will last based on current energy consumption, and more!

NOTE: Your Battleborn batteries have a 10 year limited warranty you should learn about here:
Product Manuals, Cutsheets & Data | Battle Born Batteries


If you have a 12V fridge this will run about 50HRS off of your battery with nothing else running.

When you are not plugged into shore power make sure your inverter is off.

Make sure when you are not plugged into shore power you turn off your water heater, furnace, water pump, lights, winegard, digital TV antenna, fans. These all being off will help to conserve power.

If you find that you wish for more off-grid capacity there are some very easy upgrades that can be done!

Option 1: Add 2 more GC2 battleborn lithium batteries in the exterior storage compartment where the inverter is located. This would add an additional 200Ah of lithium battery! Battleborn GC2s are about $1,000 each plus shipping.

Option 2: Replace the existing battleborn GC2's under the stepwell with an Epoch 300Ah battery or 2 Expion360 162Ah GC2s.
Epoch batteries are a great low cost option for a quality lithium battery. Expion360 is a reputable battery brand although is much more expensive. Both of these batteries have an advantage that there is an internal bluetooth battery monitoring system. Meaning you would not need to add a shunt to monitor batteries.

The 2025 Unity's are coming with a 270Ah standard battery or a 540Ah optional 2 battery system.


12V 300Ah Heated & Bluetooth LiFePO4 Battery - Epoch Essentials

12V 162Ah GC2 SmartTalk & VHC


Note on aftermarket batteries: The Expion360 GC2s are slightly taller than the battleborn GC2s so you need to make a slight modification to the top lip of the battery compartment for them to go in.

The Epoch 300Ah battery is 1/2 inch deeper than the GC2's. In some cases some of the fuses or wiring has to be moved over slightly in the battery compartment to fit this battery.