LiFePo4 charging

[buckland]

Thanks... I did it the hard way but learned s lot. Since bottom balancing (which I should have done at the start) all things seem to be working fine again. I figure whatever happens with this battery it was worth it. I like to have something to wrestle with or else I’d go nuts. I don’t watch TV so I have a ton of time to putter.

 

[buckland]

Question: Anyone who has a LiFePo4 battery...have you ever plugged into shore power ...I.e. the Iota 110 to DC to charge the battery? Does the charge controller (in my case Victron) manage the charge profile?

 

[PaulT]

Question: Anyone who has a LiFePo4 battery...have you ever plugged into shore power ...I.e. the Iota 110 to DC to charge the battery? Does the charge controller (in my case Victron) manage the charge profile?

In my 2014 Hawk, I have the IOTA DLS-30 with the external IQ4 module. I ordered a IQ4-LIFEPO from Don Rowe company
It was $18 and the specs met the Battleborn specs for charging. Works as advertised. I called Battleborn prior to orderig my batteries to make sure that charging profiles on my solar charge controller and shore power charging were compatible with the batteries.

If you have an IOTA with internal IQ4, contact IOTA to see if anything can be done to switch profiles.

Paul

 

[buckland]

Thanks Paul... I went to the site and read their material. Not sure what to do as I am a novice at these batteries but the profile does say they float charge which I was schooled these batterie don't like.....
https://www.donrowe.com/iota-iq-lifepo-smart-charge-controller-p/iq-lifepo.htm

But if this is a good thing the price is right to swap out the control module. It seems to make sense to do so as the current one is strictly for AGM (?)

 

[PaulT]

Battleborn's website discusses acceptable charging profiles and indicates that it is ok to float their batteries within a range of voltages.
"A float is unnecessary, since Li-ion batteries do not leak charge, but a floating voltage under 13.6V is fine."
https://battlebornbatteries.com/charging-battleborn-lifepo4-batteries/

You might gain some info on your unit with the Thornwave LiFePO4 battery monitor with Bluetooth app for smartphones or iPads. I added one to my Powerbox unit with 30aH Bioenno LiFePO4 battery. The same unit can be used on larger LiFePO4 systems by itself if charging and discharging is 60 amps or less. If higher current Thornwave sells shunts to acommodate the higher current.

Paul
ps. I didn't recheck if you use the Victron charger/battery monitor. In which case, you would not need the Thornwavel

 

[Vic Harder]

Question: Anyone who has a LiFePo4 battery...have you ever plugged into shore power ...I.e. the Iota 110 to DC to charge the battery? Does the charge controller (in my case Victron) manage the charge profile?

PaulT has already spoken to your concerns, and to answer your question, No, the Victron does not manage the IOTA

 

[buckland]

Thanks Vic... I am going to order the IQ4 LiFePo for the IOTA DLS-30 and take out the other module. I can count on one hand the number of times I have used shore power in 8 years but for $18 it seems sensible to do. I won't ever be going back to AGM.

 

[PaulT]

After installing my Battleborn batteries with the IQ4-LIFEPO, and reprograming my Bogart Engineering battery monitor and solar charge controller, everything has been working well.

I have one remaining power issue and finally isolated what was happening. Because I have an AGM truck battery, I did not replace the SurePower battery isolator because I did not want my LiFePO4 configured solar system charging my AGM truck battery until I better understood how it all worked in practice. I noticed that although the camper batteries had reached 99-100% at end of day, They would be down to 90-95% in the morning without anything on on the camper. I had pushed in the big chrome switch. So where was the power going?

While watching the battery monitor amps reading, I noticed about 0.8 to 0.9 amps draw on the camper batteries. The only place it could be going was forward to the truck. The SurePower battery isolataor has a solenoid that consumes about 0.9 amps to keep the relay energized. I pushed my keyfob unlock button and watched the truck interior lights come on and the amps went up to about 2.5 amps. Pushing the keyfob Lock button, I saw the amps drop back down to about 0.9 amps as the interior lights went off. Checking the truck voltage showed 13.2 volts. This is after the truck had rested for more than 12 hours and 12.5 to 12.8 volts would be more appropriate. In other words, the internal truck DC power sysem is my parasitic load. My expensive LiFePO4 batteries are float charging my truck battery and powering the always on truck systems and keeping the isolator relay energized.

Rethinking my previous decisions, I may disconnect the truck and camper electrical systems entirely.

Paul

 

[buckland]

AHA! I knew it!.... this must be where my energy went too. It happened when I plugged the camper into the truck. Since bottom balancing I have since not plugged the camper into the truck...really no need. I have the Blue Sea and could switch them back and forth but for a small gain I see no reason to have to do it. (BTW I do have the Victron with bluetooth app)
I ordered the Iota controller for the LifFePo4 .... how difficult is it to swap out the two? I have the DLS 30 with smart charger.

 

[Vic Harder]

Thanks Vic... I am going to order the IQ4 LiFePo for the IOTA DLS-30 and take out the other module. I can count on one hand the number of times I have used shore power in 8 years but for $18 it seems sensible to do. I won't ever be going back to AGM.

The marketing description of their LiFePo4 module describes both float and a maintenance cycle. I don't like the sound of that.

Paul, can you speak to what the IOTA actually does with that module in it?

 

[PaulT]

AHA! I knew it!.... this must be where my energy went too. It happened when I plugged the camper into the truck. Since bottom balancing I have since not plugged the camper into the truck...really no need. I have the Blue Sea and could switch them back and forth but for a small gain I see no reason to have to do it. (BTW I do have the Victron with bluetooth app)
I ordered the Iota controller for the LifFePo4 .... how difficult is it to swap out the two? I have the DLS 30 with smart charger.

Unplug shore power if attached.
Unscrew the one screw holding the IQ4 to the camper.
Unplug the wire (telephone connector) from the IOTA.
Plug in the IQ4-LIFEPO connector into the IOTA.
Replace the screw into the same screw hole to mount the IQ4-LIFEPO.
Plug in shore power.
Done.

Paul

 

[PaulT]

The marketing description of their LiFePo4 module describes both float and a maintenance cycle. I don't like the sound of that.

Paul, can you speak to what the IOTA actually does with that module in it?

As I recall my conversation with them, the specification is that it bulk charges at 14.6 volts until the battery stops accepting charge, then drops to "float" where it sits. If the battery is used or a week passes, the unit switches back to bulk at 14.6 volts. At the time I learned this back in May/June, I was having either telephone, email, or website conversations with Battleborn, Bogart Engineering, and IOTA asking questions to see if they were compatible. Unfortunately, conversations over telephone are lost in time and memory. Email is lasting, but other modes such as web page chats are not. A quick search of email did not turn up the specifics for the IQ4-LIFEPO. However, at the time I was satisfied that all would work together.

At any rate, the "maintenance" float mode was acceptable to Battleborn. My 30aH Bioenno LiFePO4 battery & Bioenno AC charger does the same except that I manually unplug the charger 20 minutes or more after the light turns from red to green. The delay is to allow the BMS to balance the cells.

Paul

 

[PaulT]

Dawned on me that the battery monitor was being misled by thr truck electrical system behavior. The battery monitor measures & accumulates the amp hours consumed. It then manages the solar charge controller to replace the amp hours consumed plus a little to account for conversion inefficiency.

The unit can’t determine if the amp hours consumed came from the truck battery or the camper batteries. I told the monitor that the battery capacity is 200 aH. This ignores the 85 aH of the truck AGM battery so the monitor is working from inaccurate data plus using LiFePO4 parameters on the AGM truck battery

Just disconnected the camper power wiring under the hood. Monitor now shows 0.1 amps. That is about what the monitor plus the propane/CO detector use and heard the isolator relay clunk open. Going to run it this way for a while to see how it works.

Paul

 

[rando]

Isn't the shunt for the trimetric installed on the ground wire to your camper battery?

In which case it would only be measuring the current in/out of the camper battery and it would see the truck and battery as just another load/charge source and it shouldn't affect the charging algorithm. The charge efficiency of lithium is much higher than lead acid, so make sure you change those settings as well.

 

[PaulT]

Yes. All grounds terminate on one side of the shunt including negative back to truck. One wire from other side of shunt to negative on battery. That’s how I caught what was happening.

After hitting the camper kill switch, no internal loads were active. That left the truck electrical system as the only possible load. Opening the positive to the camper at the breaker under the hood caused an immediate drop in current out of the camper batteries.
At least, that’s the only thing that makes sense to me.

With the kill switch pulled out, only the Trimetric and the propane/CO detector are energized. I made sure all appliances were off. Now I see about 0.1 to 0.2 amps which is reasonable. Turning on any light, fan, pump etc is reflected in the Trimetric amps display.

Paul

 

[buckland]

Update on the rebalanced homemade battery... the four cells seem to be staying within .03 V of each other over a week...mostly of sun with the Isotherm fridge on. Voltage drops at night to 13.1 and up to 13.45 in the day (never got higher than that). I intend to leave on LED lights today for a few hours and also the vent fan to see how it copes. We will be camping for a three day weekend coming and will be a better test. I will keep the truck and camper separate from now on. I guess I won't need my Blue Seas ACR anymore.

 

[rando]

Buckland, sounds like things are now working as they should.

What are the state of charge percentages you are getting from the BMV during this test? If your solar is only getting it up to 13.45V during the day, you may not be getting it above 60-70% SOC during the day, and maybe the solar is not keeping up with the fridge?

 

[buckland]

Okay... to be honest I don't know what a BMV is.... where do I read the % of charge? But I was thinking that it was odd the voltage never got higher even with fridge off.
I do not have my shunt hooked up but it could be as it is all there but detached. My App Victron settings are as they were set up originally.
I have a 'similar' voltage Renogy 100 flex panel I could plug in to add to the solar if you think that would help (my roof panel is 160 Watt). The manual for the Victron states I should not have two panels on the same Controller? (they are set up parallel now to a terminal block in the battery box)
Any advice to investigate?

Just thought I have the IQ4 for LiFePo4 Iota that I could attach and plug in the shore power?

 

[rando]

Sorry, BMV - Victron battery monitor (ie BMV-712). It sounds like your fridge/lights/fan may be using more power than the solar panel can put back in, but the BMV would tell you if that is the case.

You can plug in your Renogy panel in parallel - you won't get the full power out of it, but it should provide at least a little more power and maybe enough to bring your energy budget into balance.

You could also plug in the IQ4 for a few hours to get everything full, but I wouldn't leave it plugged in - even with the IQ4, the float voltage isn't ideal, also this doesn't really help with simulating real use, unless you also plug in while camping.

 

[buckland]

Thanks Lars. I have the Victron 100 20 controller with the bluetooth App but no separate battery monitor. I had the battery setting in the victron set at 13.6 V 'absorption' which I just changed to 14.2V... (not sure if this will affect anything)
I will plug in the other panel and watch it and if it does not increase I will plug in shore power (never did that before). Will get back and post thereafter (I usually use my iPhone WTW app when working in the camper but the WTW site is not allowing me to log in at this time so have to run into the house computer to post)