Eve 304 LifePO4 4S1P 12 Volt RV build and config with Epever Solar CC and Daly BMS

[BC-Steve]

Hi All,

I have complete my DIY RV Lifepo4 build. I have watch many videos and research quite a few DIY Solar forum posts. But I have not been able to locate a comprehensive guide to required configurations for the Daly BMS and The Triron Epever charge controller. I thought I understood what all the parameter mean, but not sure anymore as I do get some errors which I was able to resolve following the parameter rules in the manual. Hope someone with experience can help with appropriate settings. (I left a space for your expert recommendations). I did top balance with cells in parallel on the bench.

Component Details:

• 4x Eve 304Ah Lifepo4’s in series
• DALY smart BMS 200 amp with Bluetooth
• 40 AMP Triron 4210N EPEVER charge controller
• 400 Watt of solar panels
• 2200(4400 Surge) Watt Giandel Inverter (it was a bit expensive, but it starts and runs my AC. Awesome!)

DALY BMS

Parameter	Current Setting	DIY Solar Suggestions	Comments
Cell volt high protect	3.64V
Cell volt low protect	2.52V
Sum volt high protect	14.6V
Sum volt low protect	10.4V
Diff Volt protection	0.8V		What does this mean?
Chg overcurrent protect	100A
Dischg overcurrent protect	180A
Type of Battery	LFP/LifePO4
Rated Capacity	304Ah
Cell reference Volts	3.2V
Sleep waiting time	3600s		What does this mean?
SOC Set	n/a
Balanced open start Volts	3.3V		Given how Daly balances, seem it needs time before full to balance, therefore start at lower voltage or SOC. Pls confirm
Balance open diff volts	0.02V
Chg high temp protect	60C
Chg low temp protect	1C
disChg high temp protect	60C
disChg low temp protect	-30C
Diff temp protect	15C		What does this mean?
MOS temp protect	47C		What does this mean?
Temp charge protect	0C		Default

Some parameters came from this post: https://diysolarforum.com/threads/n...sting-a-daly-clone-bms-smart-24v-100ah.35396/



EPEVER Charge Controller

Parameter	Current Setting	DIY Solar Suggestions	Comments
Battery Capacity	304Ah
High Voltage Disconnect	14.8V
Charging Limit	14.6V
Over Voltage Reconnect	14.6V
Equalization Charge	14.6V
Boost Charge	14.6V
Float Charge	13.8V
Boost Reconnect	13.2V
Low Voltage Reconnect	12.6V
Under Voltage Recover	12.2V
Under Voltage Warning	12V
Low Voltage Disconnect	10.4V
Discharge Limit	10.2V
Equalization Duration	120 Min
Boost Duration	120 Min

There are parameter rules you need to adhere to from the manual. E.g. HVD > charge limit by 0.2V.

Questions/Comments:

• Some questions are embedded in the tables.
• What are the correct settings for the BMS and Charge controller?
• What I have is working, but does not make sense to me as, HVD should be at 14.6V(to protect the battery) but that would mean charge voltage would need to be 14.4V.
• Recommendation is to run SOC between 10-90%. How do you do this? Should it be configured at the BMS or Charge Controller or both?
• Do you have a recommendation for a heating pad? Still to be added. Pls include a link.
• The BMS has no fan L. I have driller hole in enclosure to help vent, should I add a fan? (already have 2 temp control boards)
• Is there a link for Daly BMS manual? Only have a 1 page connection sheet
• In the short term, I plan on disconnecting the vehicle charge wire, so I don’t kill the truck alternator. At some point I would what a DC-DC converter, any recommendations for a variety of amps and costs?
• My shore power charge is set to 14.6Volt and max 30Amp, current reduces to zero at battery gets close. Not sure if this is charger or the BMS that stops the charging. I think it is the BMS.

Attached some pics enjoy.

 

[rickst29]

IIRC, "Diff Voltage Protection" is a voltage differential at which the Daly BMS will shut down both the charge and discharge connections, waiting for cells to become more balanced before allowing power (in either direction) on the mains. You don't want to ever reach this value, of course - but that's a really huge differential value. My own value is 0.26 Volts.

"Sleep Wait Time" is important, and will shut down Bluetooth coms (and everything else) very quickly with that value. Daly has a "magic value" to prevent that sleep time from shutting down the BMS, that value is "15300". Change it!

Your big Inverter might want to pull more than 180A continuous for a short period, I would raise that number to at least the labeled value of 200A.

"Balance Open Start" will supposedly shut down charging from the mains, and begin to use only the differential voltages on the balancing wires to balance the cells. So don't set too much lower than the maximum Voltage which you want to get from "main" float charging, maybe 3.45 or so.

I have no idea what "diff Temp protect" is supposed to mean, and I was advised to change my value to 255 degrees (C) - to make sure that it never gets in the way. (It may refer to a differential between internal MOS temperature versus external temp probe temperature.)

I would raise your "chg low temp protect" to be at least a couple of degrees ABOVE freezing, maybe 4C would be good.

I would not adjust the MOS temp protect.

 

[rickst29]

You MUST disconnect the "vehicle charge wire", and replace it with a regulated DC->DC voltage boosting charger. Without that disconnect or new intermediate device, your lithium battery pack will discharge into your starter battery (all the time), and your EpEver "Boost" will also be feeding the starter battery - even when it is full.

 

[rickst29]

I would not charge your batteries to such high voltage. "Float" of 13.8V is extremely aggressive, and would shorten battery lifespan if it could actually bring the batteries up that high. (Note that your "Balance Open Start" will prevent it from getting that high.) Pushing the pack up to 13.8V would gain less than 1% additional capacity versus 13.6v, which I use. A lot of people on the forum prefer even lower values, all the way down to 13.4 and even 13.3V.

"Balance Open Start" is the cause of charge termination from your shore power charger.

Also, your low voltage reconnect is awfully high. IIRC it should be set somewhat lower than the two "warning" values, although I could be wrong about that.

 

[BC-Steve]

Thanks @rickst29. I will update.

Any advice on Charge controller?

 

[rickst29]

Thanks @rickst29. I will update.

Any advice on Charge controller?

Probably reduce "Float" per previous post (13.6V) and "Boost Reconnect" (13.0V). OverVoltage reconnect = 14.7, because EpEver should remain connected (at least) while the shore charger is running.

 

[mikefitz]

You need to consider the BMS is a 'last resort' protection device for the battery, not a mechanism to control charging.

The BMS settings have been disussed.

10 to 90 SOC concept. The 90% soc is determined by the charger but in practice is difficult to achieve. A safer and less stressful charging process is to charge to 13.85 or 14.00 volts with short absorbtion period. Float volts ar 13.40.
With your battery and charge currents will give over 90% soc, perhaps nearer 99%. The low end is easy , set the lvd on the inverter to 12 volts.

The settings on your shore charger are too high causing bms shutdown.

The Tracer solar charger has settings for the load outputs and settings that determine charging.

Determine what charge voltage you want to use, Boost Charge voltage = absorbtion voltage
Determine what boost duration you need, Boost duration = absorbtion time
Determine what float voltage you need.
Determine at what voltage you want the controller to exit float and re apply boost volts.
Equalise charge volts and duration are not needed for lithium batteries.
Temperature compensation is not needed for lithium.

All other settings relate to the load outputs.
You inverter and camper DC loads will be connected to the battery so load output protection values are not applicable

My suggestion; ( others may have different views)

Equalisation charge volts 14.0
Boost charge volts 14.0
Float charge volts 13.4
Boost reconnect volts 13.2
Equalisation duration 0
Boost duration 10 minutes
Temp compensation 0

When you decide on a DC to DC charger for engine charging consider similar charging voltages.

I cannot help with the Daly BMS, its not type I use or recommend.

Mike

 

[BC-Steve]

Thanks @mikefitz. Very helpful. Once I have digested all input I will update my table for others to benefit

 

[BC-Steve]

I have a follow up Solar and Lifepo4 battery question: While the trailer is at home and not being used, should my solar be turned off as there is very little daily draw so the battery remains close to full. Note: current full charge is 13.7V and SOC shows as 99%. Individual cell are at 3.425V.

Soon we will be regularly using it and the fridge will remain on, I could leave the inverter on and run the fridge on auto. This will create a pretty big draw. Not sure if my 400W solar will be able to fully recover on a daily basis. Joys of living in BC.

Thanks for any input.

 

[Shep]

Thanks @mikefitz. Very helpful. Once I have digested all input I will update my table for others to benefit

Did you put your new parameters in Steve? Would be good to see the updated chart you're using. ? how has your setup been working out for you these last few months?

 

[BC-Steve]

As requested, below are the BMS and Charge controller settings I have been using. Seems to work fine after one season. If you think it needs adjustment, please comment. I have built 2 more similar batteries for friends and family, then have different charge controller systems, but I provided these parameters as guide for selections on their system ( GoPower and Renergy all-in-one units)

DALY BMS

Parameter	Current Setting	DIY Solar Suggestions	Comments
Cell volt high protect	3.64V	3.64V
Cell volt low protect	2.52V	2.52V
Sum volt high protect	14.6V	14.6V
Sum volt low protect	10.4V	10.4V
Diff Volt protection	0.8V	0.26V
Chg overcurrent protect	100A	100A
Dischg overcurrent protect	180A	200A
Type of Battery	LFP/LifePO4	LFP/LifePO4
Rated Capacity	304Ah	304Ah
Cell reference Volts	3.2V	3.2V
Sleep waiting time	3600s	15300s
SOC Set	n/a
Balanced open start Volts	3.3V	3.45V
Balance open diff volts	0.02V	0.02V
Chg high temp protect	60C	60C
Chg low temp protect	1C	3C
disChg high temp protect	60C	60C
disChg low temp protect	-30C	-30C
Diff temp protect	15C	15C
MOS temp protect	47C	47C

EPEVER Charge Controller

Parameter	Current Setting	DIY Solar Suggestions	Comments
Battery Capacity	304Ah	304Ah
High Voltage Disconnect	14.8V	14.8V	Rules require 0.2V > OVR
Charging Limit	14.6V	14.6V	Left to meet param rules.
Over Voltage Reconnect	14.6V	14.6V
Equalization Charge	14.6V	14V
Boost Charge	14.6V	14V
Float Charge	13.8V	13.4V
Boost Reconnect	13.2V	13.2V
Low Voltage Reconnect	12.6V	12.6V
Under Voltage Recover	12.2V	12.2V
Under Voltage Warning	12V	12V
Low Voltage Disconnect	10.4V	10.4V
Discharge Limit	10.2V	10.2V
Equalization Duration	120 Min	0min
Boost Duration	120 Min	10min
Temp charge protect	0C	4C

BTW for car connection, I simply disconnected the trailer wire, so the charge wire is not connected.

 

[Enduro]

Found this manual on a german site. It's a rebranded Daly

Xenes BMS2

 

[Skari]

is this a RV or a caravan? just curious about alternator charging as on my RV I simply tried using the battery in parallel and found the charging current to be acceptable if not slightly underwhelming @25A and there is of corse a cut off relay that vill prevent it from discharging in to motor battery (no DC-DC charger needed). Other then that I would leave the Diff Volt protection higer and start the Balanced open start Volts lower as if Im understanding the charger setting it stops @ 14V and @ that it is only around 90% charge?

 

[HRTKD]

For a LiFePO4 battery bank, you want equalization time set to zero so that equalization doesn't happen. Equalization is a lead acid battery process that can exceed the 14.6 volts we never want LiFePO4 to go over.