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Two year old Relion 100-HP battery bank going south rapidly

Ah now we're getting somewhere. Your problem is because Progressive Dynamics has NOT A CLUE how to charge LiFePO4 batteries. They simply slapped a "Li" profile (Li batteries are not rechargeable so really should be Li-Ion or LiFePO4 this shows how little they actually know) on a constant voltage power supply.

Your charger NEVER drops to float. It provides 14.6V forever or until you manually turn it off.

Sadly you're not the first person to be mislead by BS marketing by a lead acid charger company who has not a clue what they are doing. We get called to cunult of a few RV instllations and we've seen this same charger ruin more than a handfull of banks and we're not even in the RV industry.

Scrap that boat anchor of a charger and get a real charger, one that is 100% custom programable (Victron IP22 or Skylla IP65) for your next set of Relion batteries.. This is not the fault of Relion it is 150% the fault of Progressive Dynamics.

This industry has become the wild west of BS..... So damn frustrating...
Thank you for your info/opinion. I read that PD was a decent charger and one of the better chargers. More BS I suppose if what you say is true. Now the real problem. My batteries are not sitting on a bench inside a very large room within a very large building. RVs are a fine example of 10 pounds of crap in a 5 pound bag. I will need a charger that will replace the unit that is inside WFCO power panel, as did the Progressive Dynamics replace the original lead acid charger/power supply. These are not just chargers. They need to function as DC power supplies for the RV when they are powered up, supplying RV power while charging the battery bank or when the battery is off-line or missing. I'm not sure if there is an actual difference here in overall charger/power supply design. I guess it's back to the drawing board for me, researching converter/charges for lithium batteries... maybe... if what you say is true. I don't see how PD can exist without severely bad reviews or is this going to all come to a head as the data rolls in? Being an early adopter has it's risks.

Question: Would I be better off going back to the original, I think settable, lead acid charger from WFCO if I can't get something to fit?
 
Thank you for your info/opinion. I read that PD was a decent charger and one of the better chargers. More BS I suppose if what you say is true. Now the real problem. My batteries are not sitting on a bench inside a very large room within a very large building. RVs are a fine example of 10 pounds of crap in a 5 pound bag. I will need a charger that will replace the unit that is inside WFCO power panel, as did the Progressive Dynamics replace the original lead acid charger/power supply. These are not just chargers. They need to function as DC power supplies for the RV when they are powered up, supplying RV power while charging the battery bank or when the battery is off-line or missing. I'm not sure if there is an actual difference here in overall charger/power supply design. I guess it's back to the drawing board for me, researching converter/charges for lithium batteries... maybe... if what you say is true. I don't see how PD can exist without severely bad reviews or is this going to all come to a head as the data rolls in? Being an early adopter has it's risks.

Question: Would I be better off going back to the original, I think settable, lead acid charger from WFCO if I can't get something to fit?
Thank you all for the ideas and contributions regarding this unfortunate incident. I now have 3 new batteries thanks to Relion who quickly covered their warranty agreement. Batteries have been individually charged, rested, interconnected in parallel and are now stabilizing with no load or charge voltage/current. Later today, after stabilization is complete, the new battery bank will be brought online.

I have changed my PD4655LIV charger configuration to the WildKat mode (board jumper and remote monitor/switch) to enable 3 stages of charging, as in lead acid charging. This will cause the charger to operate at a slightly lower voltage. I won't really get a full charge without manually going to boost mode, but it will stop the constant 14.6 volt charge when not needed, a possible cause of the batteries' early demise.

Now, for anyone who has been following and is interested, here is a charge profile of one of the new batteries, which is only partially charged when shipped. Also, for the self-proclaimed battery experts out there, a bit of advice. If you have battery monitoring tools, learn how to use them, and if you don't, get them.

Of special note here: Notice the clean lines of the voltage and current readings. This is a bit different from the earlier posting of the damaged batteries. The profile snapshot was taken during the later stage of the charge, but you already knew that by looking at the initial charge voltage on the graph. Right?
 

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I have changed my PD4655LIV charger configuration to the WildKat mode (board jumper and remote monitor/switch) to enable 3 stages of charging, as in lead acid charging. This will cause the charger to operate at a slightly lower voltage. I won't really get a full charge without manually going to boost mode, but it will stop the constant 14.6 volt charge when not needed, a possible cause of the batteries' early demise.
These batteries have a built-in BMS that is supposed to prevent excess charge or discharge, right? So why would it matter if the charger voltage sat at 14.6V? Wouldn’t the BMS disconnect the cells at some lower (safe) voltage?
 
These batteries have a built-in BMS that is supposed to prevent excess charge or discharge, right? So why would it matter if the charger voltage sat at 14.6V? Wouldn’t the BMS disconnect the cells at some lower (safe) voltage?

14.6V / 4 cells per battery = 3.65V is maximum voltage that should be applied. People normally top balance to this voltage, then operate at a lower voltage. Perhaps it is OK to charge to this voltage but stop when current tails off, if trying to reach 100%.

The battery continues to charge when held at an elevated voltage, and will eventually over-charge. A lower constant voltage should be used during operation, e.g. 3.40V/cell, and they stop charging around 95% to 98% for longer life. But if charger (and BMS) limited charge voltage to 3.4V it would take far longer to complete charging.

The BMS is an emergency disconnect for high/low voltage and excessive current. Hopefully also for temperature too hot and too cold. BMS does not have electronics able to gradually vary voltage and current. To do that with linear/analog regulator would take more FETs, big heatsink, and would be inefficient. It is best done with a switching power supply. That is where the charge controller comes in. If charge controller is set correctly, BMS should never disconnect except for temperature (because charge controllers don't have that protection.) Beyond that, BMS provides cell balancing.

BMS is basically a cheap and dumb circuit breaker. Charge controller needs to be programmed to optimize for the battery. But most of those are fairly simple, so you have to operate within a few parameter limits that avoid battery damage, and can't operate near the battery's capability limits. In particular for temperature. LiFePO4 battery usually has spec of 0.5C charge rate, but that is only near 25 degrees C. If you are charging around 5 degrees C, it appears battery could be damaged by more than 0.1C. The charge controllers don't offer variable current vs. temperature. All you get is maximum current and minimum temperature. So you have to set those two parameters to "do no harm" and accept either reduced charging at all temperatures above freezing or no charging in cool temperatures.
 
Relion battery is the almost same like BB battery, using the 26650 cells inside, i believe Relion using the battery cells from Ocelltech, https://www.ocelltech.com/html/dianxin.html , it depends on what cycles life battery cells Relion choose, Ocelltech provide different cycles for option. Normally , the capacity would not drop down rapidly in a short time.
 
Any and all Lithium batteries need to be charged to 100% weekly or so to both calibrate the SOC meter and to balance the cells. Unless you are planning on keeping the batteries for 10-15 years, don't worry about charging to 100%. In addition, almost every RV inverter will charge to 100%.

Regards Mike Mas
 
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