New Epoch 300AH Essential Battery, all going well except…

[routlaw]

Finally took the plunge and ordered a LiPO battery from Epoch. For now only going with one given what little DC we have consumed in the past. Install was fairly easy except for the massive clean up of rust, battery acid deposits on tray and battery cabinet. Half the screws mounting the slide out tray were rusted past re-use. No big deal on that.

Still using the Blue Sky Solar Controller 3024iL with IPN Pro Remote. Made sure to set proper parameters before installing the battery and based on a phone conversation with Epoch they stated 14.2 bulk, 14.2 absorption, and 13.6 float. The system has been charging all day, however at only 13.6 volts although the IPN Remote says its in bulk mode. The day has been very sunny, with a few puffy white clouds floating by periodically. In the past with lead acid batteries I have easily been able to get well into 15+ amps for a long equalization charge. Have double checked all my settings a couple of times throughout the day and they are correct but still no 14.2 volts on the charge. Suffice it to say it's going slow.

Battery was at 46% out of the box and half an hour ago now at 70%.  Is this normal? Probably not, but anyone have any ideas on what might be going on?

Thanks in advance

[Rolind]

I’m not sure I understand your current status correctly, but if you have a 300Ah battery with 46% charge, you needed 162 Ah till full charge. Depending on weather and sun angle, and assuming you have a PWM charge controller, you probably on got 15Ah of charge for 5 hrs, and significantly less for the rest of the day. Maybe 7Ah for 7 hrs. So yield for today would be 124 Ah for a current battery deficit of 38Ah and SOC of 88%. This is not too far from your reading of 70% SOC . I would give the system another sunny day or two to catch up and see where things settle. I think you are in great shape overall.  I am assuming you have the 300 Ah epoch battery, if you have the 460 Ah battery you are probably even closer to 70% SOC. Lastly, I am not familiar with epochs BMS, but on our lithionics, sometimes the SOC reading has drifted and is not correct and doesn’t reset until voltage reaches full charge. Hope this helps.

Edited May 9 by Rolind

[topgun2]

Perhaps another thing to take a look at is the routing of your main negative cable versus the location of the shunt that feeds information to the IPN remote.  If you did not change this routing when you replaced the batteries and you use your inverter it could have effects on the readings you are getting.

For some unknown reason, the main negative cable is wired directly from the battery to the inverter - i.e. not through the shunt.  

The rest of the negative flow DOES go through the shunt first.

Obviously, this arrangement affects the readings that you will get via the IPN Remote.

Bill

[mossemi]

For the sake of calculations, I believe the Blue Sky Solar Controller 3024iL is a MPPT type solar charge controller.  Since this is the first time charging the battery for this installation, Rolind's comment about the SOC and the BMS is correct.  The SOC is a calculated value and drift is a common occurrence.

Mossey

[routlaw]

47 minutes ago, mossemi said:

For the sake of calculations, I believe the Blue Sky Solar Controller 3024iL is a MPPT type solar charge controller.  Since this is the first time charging the battery for this installation, Rolind's comment about the SOC and the BMS is correct.  The SOC is a calculated value and drift is a common occurrence.

Mossey

Thanks. Correct the BS 3024iL is a MPPT type of solar charger. I may need to clarify a few things. I am not all that concerned with my SOC so much as to why even in bulk charging mode the charge rate is only 13.6 volts vs the 14.2 that I programmed in the IPN Remote. Even on a sunny brilliant day it never got past that value when in the past with my lead acid batteries I could easily get well into the 15+ volts with equalization mode. Just doesn't make sense to me, unless as @topgun2 stated it might have something to do with the routing of the negative cable. I did not make any changes what so ever when I installed the new battery. Just didn't see the need to consider it. 

[routlaw]

1 hour ago, topgun2 said:

Perhaps another thing to take a look at is the routing of your main negative cable versus the location of the shunt that feeds information to the IPN remote.  If you did not change this routing when you replaced the batteries and you use your inverter it could have effects on the readings you are getting.

For some unknown reason, the main negative cable is wired directly from the battery to the inverter - i.e. not through the shunt.  

The rest of the negative flow DOES go through the shunt first.

Obviously, this arrangement affects the readings that you will get via the IPN Remote.

Bill

Thanks Bill. No I didn't change anything at all other than hooking the main cables onto their respective terminals on new battery. It never occurred to me this might be necessary. I will check this shortly to see how the cables were originally routed. This begs the question why would it be different for the lead acid batteries vs the new Lithium in regards to the charge voltage of only 13.6 vs the 14.2 I programmed into the IPN Pro Remote?

Rob

[mossemi]

I had forgotten about Bill's Lithium installation and the issue he found with his shunt.  When you are investigating your battery cable’s, be sure that every negative wire or cable is on the correct or load side of the shunt.  There should only be a single negative wire or cable attached to the negative battery post.  When wired correctly, the shunt will have the ability to read all 12V usage.  Does the Epoch battery have an app the you are reading the SOC with or are you reading the Blue Sky remote?

Mossey

[routlaw]

13 hours ago, Rolind said:

I’m not sure I understand your current status correctly, but if you have a 300Ah battery with 46% charge, you needed 162 Ah till full charge. Depending on weather and sun angle, and assuming you have a PWM charge controller, you probably on got 15Ah of charge for 5 hrs, and significantly less for the rest of the day. Maybe 7Ah for 7 hrs. So yield for today would be 124 Ah for a current battery deficit of 38Ah and SOC of 88%. This is not too far from your reading of 70% SOC . I would give the system another sunny day or two to catch up and see where things settle. I think you are in great shape overall.  I am assuming you have the 300 Ah epoch battery, if you have the 460 Ah battery you are probably even closer to 70% SOC. Lastly, I am not familiar with epochs BMS, but on our lithionics, sometimes the SOC reading has drifted and is not correct and doesn’t reset until voltage reaches full charge. Hope this helps.

Correct I do have the 300 AH Essential should have stated that in my OP. I am not so concerned with the SOC so much as why my max voltage all day was throttled at 13.6 vs the 14.2 volts I had programmed into the IPN Pro Remote. It was a clear sunny brilliant day with only a few clouds rolling over periodically. On similar days with the old LA batteries I could easily obtain over 15 volts charging for equalization. Otherwise yes your math is close enough. This morning I am at 72% with 215 amps with a Volt Diff of only .001 volts indicating the cells are very close to a balanced state from the factory. 

Thanks for the input.

[ScubaRx]

24 minutes ago, routlaw said:

…This begs the question why would it be different for the lead acid batteries vs the new Lithium in regards to the charge voltage of only 13.6 vs the 14.2 I programmed into the IPN Pro Remote?

Rob

Back when your trailer was built, they didn’t understand all the nuances of the solar system that I designed for them. The then “service manager” just couldn’t grasp the notion that all the negative wires had to go through the shunt first or the IPN Pro would not calculate the SOC properly. Most likely, the negatives from the solar controller and possibly the charger also, go directly to the negative terminal on the battery. There really should only be two wires coming out of the battery box. I moved everything else out of the box and onto some massive buss bars. 

[topgun2]

38 minutes ago, routlaw said:

This begs the question why would it be different for the lead acid batteries vs the new Lithium in regards to the charge voltage of only 13.6 vs the 14.2 I programmed into the IPN Pro Remote?

I asked that very question except my question was more slanted to why did Oliver include only the DC side in going thought my shunt.  Jason Essary's answer was - I have no idea.

Since I rarely use my inverter (with either the old lead acid or the new lithium's) I've not changed this wiring - yet.  But, I will at some point in the future and certainly I would change it if for some reason I started using my inverter more.

Bill

[routlaw]

1 hour ago, ScubaRx said:

Back when your trailer was built, they didn’t understand all the nuances of the solar system that I designed for them. The then “service manager” just couldn’t grasp the notion that all the negative wires had to go through the shunt first or the IPN Pro would not calculate the SOC properly. Most likely, the negatives from the solar controller and possibly the charger also, go directly to the negative terminal on the battery. There really should only be two wires coming out of the battery box. I moved everything else out of the box and onto some massive buss bars. 

Good info Steve. Curious I currently have two red wires coming into the battery box and one yellow. I assume one of the red wires goes to the Power Dynamics Charger/breaker panel while the other goes to the Solar Charger. Note one red wire is 6 AWG while the other is probably 10 AWG (can't tell yet for sure. However at least in my case upon further examining I do have a yellow wire going into my shunt but need to chase it back to make sure it's the going directly into the battery compartment. Lots of distractions this morning. 

[routlaw]

FWIW in the conversation I do not have an inverter in system other than a small we occasionally use for charging phones, tablets, and computers via the 12 volt plugs in the cabin. Just haven't found much need for anything more than that so far. 

[routlaw]

Turns out my unit was wired correctly, the yellow wire from battery compartment goes into one side of the shunt and on the other terminal a yellow wire runs straight to the Power Dynamics Panel. Special treatment I guess, odd that others did not have it wired correctly. Thanks for the heads up on correct wiring. 

[jd1923]

2 hours ago, routlaw said:

why even in bulk charging mode the charge rate is only 13.6 volts vs the 14.2 that I programmed in the IPN Remote.

Rob, I hardly ever look at the IPN remote (pic1) since I have added a Victron SmartShunt at the main battery ground and use Victron and Epoch apps instead. The IPN remote screen shows +25.6A charging at 13.7V. I suggest, Ignore the voltage number knowing that the Blue Sky MPPT is supplying +25.6A to the batteries, hence it is charging!

If a battery is at say 13.3V and the charger is trying to push 14.2, the reading cannot be 14.2 since it is connected to the battery at a lower voltage. Voltage readings are potential of the circuit, NOT what you have set Bulk charge to, the 14.2V Epoch spec. We have four (4) chargers; the Blue Sky MPPT, Victron 30A MPPT for suitcase solar, Victron 120A Multiplus II and Orion XS 50A DC-DC chargers, all set to the Epoch specs of 13.6V and 14.2V as you have on your IPN remote interface to your Blue Sky MPPT charger. I have never seen the 14.2V bulk charge rate on any of these chargers. I see 13.6V or 13.7V and never higher.

Get the Epoch app loaded on your phone. The app is free and I have found you can only count on a reliable SOC% via the Epoch App measuring battery SOC internally (pic2). The screen capture on the left was taken when I started the TV, Orion DC-DC and Blue Sky chargers combined providing net +47.3A to the batteries at 59% SOC. The screen to the right shows battery SOC at 81% hours later after we parked at a campsite, engine off (hence DC-DC charger OFF) and with less sun later in the day and fridge still on DC the batteries are supplying net -5.7A. Note that voltage measured at the batteries was only 13.4V when the DC-DC charge was ON (not pictured, it was 13.7V measured at the charger) and after the charger was OFF battery voltage was 13.3V.

The Bottom Line: There is nothing wrong with your system as wired as long as you are seeing +A on the IPN Remote relative to the amount of available sunshine. I get >+20A when the sun is good, closer to +10A early or late in the day or when partly cloudy. Good thing your noticing these things. Get the Epoch app to read your battery SOC%.

[routlaw]

@jd1923 Actually I have had the Epoch app from the start or actually before the start so am familiar with all of its helpful information. Just got off the phone with Ryan Gurin at Blue Sky a short while ago and he explained the discrepancies I thought I was experiencing with charging. I am now at 88% SOC so it is moving along well with this perfectly clear sunny day. Charging amps are reading at 13.7 + which is about right for my 320 watt panels, and as Ryan indicated as the system becomes closer to full the voltage should increase to 14.2 but only for a short time. Which might be the reason you have not seen it at that value. 

What's important here and for others who might come across this discussion later as they adopt LiPO batteries is due to my very weak acid batteries the voltage was able to shoot up almost immediately to 15+ volts indicating a very weak battery bank. Because I now have a new battery in good condition this will not happen until the SOC is near or at full. I don't know the science behind this but Ryan was emphatic this is the way things work with bad vs good batteries. So for anyone who is experiencing a rapid increase of voltage within a minute or two from turning your solar on or plugging into shore power it is a dead on indication of very weak battery bank that should be replaced.

One thing you can check on via the IPN Remote is the max and min voltage your battery bank has experienced via the menus which should indicate if your bank has ever hit 14.2. Thus far I have kept the Power Dynamics out of the loop since its charge current is 14.4 amps and non adjustable as far as I know. Tech support at Epoch stated they like to see the first several charges at a max of 14.2 as it is more "gentle" on the new circuit parts until they are broken in. Sorry I don't recall what those parts were within the BMS but he was serious about letting things break in slowly and easy initially. Fine by me as I rarely use shore power. 

Thanks for the help and info. 

[routlaw]

Quick update. Battery fully charged now while I was out on a bike ride. System seems to be making an effort to balance the cells from what I can tell. Upon returning the battery was indeed at 13.9 volts with a -.2amp discharge in progress. Checked the history with minimum and max volts and sure enough it did hit 14.3 volts at some point before going into float mode. I suspect within the hour it will rest at 13.6 volts in float at the rate it's going. 

Hope this helps others to understand the process when upgrading batteries. It sure had me confused for a day. A lot of excellent input on the situation, thanks all.