Mixing Ecoworthy and EG4 Batteries

[oreo9001]

I have searched but have not yet found a great answer.

I'm hoping to take advantage of the Ecoworthy 48V server rack price. With Will's code, free shipping, AmazonCC 5%, and the 30% solar tax credit, I can get two Ecoworthy 48V units for $1,099.

I have a 6000XP and three Lifepower4 V1 batteries in a rack. This setup powers a small weekend cabin in northern Wisconsin. The Lifepower4s have been mostly sufficient in the winter, but I sometimes need a bit of extra power on cloudy or snowy days. I have maxed out the solar capacity for the 6000XP and am considering three scenarios:

1. Parallel them all and have communication only with the Lifepower4. I saw another member mention that this is possible. Is that correct? I'm unsure.

2. Run them all without communication. Is this the best option?

3. Parallel them all but turn off either the EG4 or Ecoworthy at the circuit breaker—essentially creating two battery banks that are both connected to the same busbar. I'd switch to the EWs when the EG4s are low. I'm not convinced this will work, but I'm curious if it would.

Thanks for the help.

 

[sunshine_eggo]

1 or 2 with no preference.

Absolutely, positively NOT #3.

 

[timselectric]

Boom

 

[oreo9001]

Thanks for your help @sunshine_eggo

I will steer clear of option #3...but..to help build my understanding, why is it not a good idea? My two guesses are that there is a risk of switching on/off the wrong breaker and/or that there will still be voltage with the built-in circuit breaker off. Am I close?

 

[Wolfpack7483]

I've got 2 EW's in parallel with a Vatrer & an EG4. I run open loop to an EW all in 1 (rebadged SRNE HYP) with no issues. I have the EG4 communicating to SA & monitor the others through Bluetooth.

 

[sunshine_eggo]

Thanks for your help @sunshine_eggo

I will steer clear of option #3...but..to help build my understanding, why is it not a good idea? My two guesses are that there is a risk of switching on/off the wrong breaker and/or that there will still be voltage with the built-in circuit breaker off. Am I close?

You have two outcomes when switching back and forth:

1) completely cutting DC power to the system to prevent surge between the batteries.
2) potential surge between batteries at notably different voltages, which could trigger short circuit protection. And why cut your battery capacity by 40-60% requiring a manual operation to fully utilize your battery bank?

 

[Wolfpack7483]

You have two outcomes when switching back and forth:

1) completely cutting DC power to the system to prevent surge between the batteries.
2) potential surge between batteries at notably different voltages, which could trigger short circuit protection.

I used to think 2) was a much bigger deal, than it seems to be in reality, at least in my case. I was careful to extreme, that voltages were the same when paralleling. A while back I decided to see what happens when they were a coouple tenths off. It was only a surge of about 2 amps. This past weekend, I removed the EW v1 to top balance with an Enerkey 4a active balancer. After balancing, it was obviously @ 100% SOC.

I put the EW back in service by itself, in order to cycle it. After cycling to 15% & back to 100%, I was trying to figure out how to integrate all 4 back together. The others were around 35% SOC. Decided to bring 1 @ a time into parallel, to see what happened. I did isolate from the system before paralleling. When I added the EG4, the surge from the EW was around 20a. Within about a minute or so, this had decayed to 10a. I then added the Vatrer, and the surge went from 10a to 24a. Rinse and repeat with the other EW, with similar results.

I wouldn't have tried to parallel the EW with the other 3 all at once, but doing it 1 at a time wasn't a problem. The EW did take a disproportionate share of the load for several hours as SOC's balanced out. I wouldn't hesitate to do this again, as I've got runner cells in the other EW & the Vatrer to balance out still.

 

[sunshine_eggo]

#2 can be overstated, especially when you consider the additional resistance in the connection. When looking at cell resistances alone, and talking about bigger cells like 280Ah that are at 0.20mΩ resistance, there's a theoretical surge of 150A @ 1V difference.

Andy at Off Grid Garage did this with two cells at 0 and 100% SoC... saw north of 200A.

Once you add in interconnect, internal and external wiring/connection resistances, it tends to be much lower.

The question becomes, why design it into a system? Why not parallel same with same and let it run that way instead of cutting your bank capacity by 40-60% and forcing a manual operation to use all of it.

I've revised my answer.

 

[oreo9001]

Thanks for the helpful advice, all.

One last question. If I go with option #1 (parallel and communicate only with the Lifepower4s) will the SOC be somewhat accurate and does the 300ah setting (set by the 6000xp) matter since I'll actually have 400ah? This is a second property and I monitor it remotely. I need to know the data I'm seeing is accurate from afar. Thanks!

 

[wpns]

Yeah, 1, maybe 2, never 3

 

[Samjam]

Sorry - don’t mean to hijack this thread…
How does RSD (battery side) work in option 1 and 2?

 

[wpns]

Sorry - don’t mean to hijack this thread…
How does RSD (battery side) work in option 1 and 2?

Probably depends on the batteries and how RSD works with each brand.

EG4 RSD on the WallMount OutDoor PowerPro batteries works really well, but is such a nightmare to recover from that I’ve disconnected the RSD switch from the primary inverter.

 

[BarracudaBob]

As long as you get them up to their BMS 100% SOC reset voltage and hold them there to balance they will play nicely together.

I just did a test of three different battery capacity and types. Everybody working nicely together

Post in thread 'ECO-WORTHY 51.2V 280AH 14.34 KWh Beasty Battery'

Mar 19, 2025

I ran the beast with the other 12 100aH Rack Batteries all in parallel and had mini-split, hot tub, and pool immersion heater going all night. Not a heavy load but I was mainly interested in how much each battery the capacity would go down.

Ironically they all seemed to have about the same SOC. There are cable lengths differences, different places where they land on the breaker panel and all those deviations between brands but overall they track each other nicely. I wasn't sure if the 280Ah would have a higher SOC but in the big picture they are all working together.

I love it when a...

• BarracudaBob

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