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ECO-WORTHY 48V 100Ah 5120Wh LiFePO4 Server Rack Battery

I got all 7 of my EW batteries this week and mounted in the rack. I am going to get all the data lines setup and see how far out of whack things are. Most of them are around 35% SoC.
What sort of rack did you use?
 
Just a stock battery with no active balancer. Going capacity testing and playing with BMS and learning about how they work. 10mV deviation at 57V, oh ya! Balance it and deep cycle it a few times and zero issues.

Playing around and testing capacity on this thread proving that the BMS is stopping discharge based on SOC before LV disconnect. I expect this test to trigger LV. Immersion heaters in the pool so I don't waist any watts ;)
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I've posted earlier in this thread about the balancing issues I've had with my V1 EW, V1.5 EW, & my V1 after BMS transplant. I kept having issues with "runner cells" taking out the charging FETs due to single cell overvoltage. The runners would be around 200 mV higher than the lowest cells at trip, so the batteries could never get to full voltage.

I'm extremely pleased to report that this is no longer an issue with either battery. I had a few issues getting there. The 1st Neey 4a active balancer I bought was DOA & the bolt on the stud for the balance lead on cell 15 of the V1 seemed to be welded on. I ended up removing the stud & installing a new bolt in it's place.

I ordered the Enerkey 15-16s 4a active balancer from Amazon to replace the DOA Neey. I balanced both batteries, holding the cells at around 3640 for a couple of hours. I had to pay close attention towards the end, adjusting the current from my power supply down to as low as 10 mA. I did keep the BMS on during this operation, as BMS balancing wasn't going to happen, because cell delta wouldn't get high enough. I monitored BMS cell voltage as well as from the Enerkey app. The BMS reported slightly higher voltage than the Enerkey app. I kept the voltages just below the 3650 limit of the BMS.

After a couple of deep cycles, I now have all cells in both batteries playing nicely together. Thanks to BarracudaBob for suggestions on how to top balance. I never thought it would have as dramatic effect as it did. I'm now a firm believer in top balancing on battery delivery, assuming the cells aren't already properly balanced!
 
Adding external antenna for Bluetooth and Wi-Fi.
Warning the connector was glued down with epoxy on the PC board. It's going to take some doing to get it to where I can plug this one in...

I think the antenna with the MAC address right behind it makes a great selling point. It definitely gets people's attention wow that thing's got an antenna cool 😎

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Update: Here is a warning for those who dare replace or take out the BMS. The bolt on the negative and positive terminal going to the batteries from the BMS are pressed in bolts on aluminum busbars. You try unbolt the terminals and they will spin. I just had to cut out the negative bolt to get this BMS out (safely). Also the replacement BMS that some of us got in the beginning have larger bolts on the Positive and negative BMS terminals so I have to drill out the terminals so the bolts go through. Also while trying to remove the epoxy the socket on the WIFI/Bluetooth broke. I now have to replace the SMD receptacle for the antenna. I am swapping the BMS out and will use this as a test on a Frankenstein battery. Really opened up a can of worms here. This was all of my own dewing.. To add insult to injury my chargeverter is acting strange so I'll end up taking that apart.. They say it happens in three's so I am on guard now :oops:

Short answer: Don't mess with it. If it works don't fix it... I am a fiddler but this quick project just became a full BMS swap out. Save your self the acervation:eek:

Update 2: Installed and working after reprogramming. Antenna makes 20 DB difference. Just move it to the breaker and be happy... Chargeverter started working again after sitting for an hour.. ?! Some days are easier than others..
 

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This rack thing is a real issue I really hope that someone provides an inexpensive one especially E-W comes out with something that's reasonable if they make it where it'll take 6U batteries it'll sell like hotcakes. Understandably I can see where you don't want your competitor's batteries in your Rack. It does seem like everybody's going to the 3U size.

Is it safe to say that everybody wants wheels?

I know I sure love them 🤘😁
 
This rack thing is a real issue I really hope that someone provides an inexpensive one especially E-W comes out with something that's reasonable if they make it where it'll take 6U batteries it'll sell like hotcakes. Understandably I can see where you don't want your competitor's batteries in your Rack. It does seem like everybody's going to the 3U size.

Is it safe to say that everybody wants wheels?

I know I sure love them 🤘😁
So far this rack is pretty stable with all 7 batteries in it. Though my shed floor is another story... (reinforcing it today :0))

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The wheels concentrate all of the load in 4 tiny places, which is potentially a really bad day on a wood floor. Especially on modern construction that uses OSB for subfloors.

If you want to use wheels for something so heavy on a wood floor, anchor it to the wall so when the floor deforms the rack won't fall over.
 
The wheels concentrate all of the load in 4 tiny places, which is potentially a really bad day on a wood floor. Especially on modern construction that uses OSB for subfloors.

If you want to use wheels for something so heavy on a wood floor, anchor it to the wall so when the floor deforms the rack won't fall over.
Yea thus my floor reinforcement comment. I have some 3/4" baltic birch that I am going to put down and also more support for the OSB from underneath. Then I will also anchor it to the wall with lags.
 
So far this rack is pretty stable with all 7 batteries in it. Though my shed floor is another story... (reinforcing it today :0))

View attachment 280109
Those small casters scare me. I'd be more concerned with upgrading them before strengthening the floor.

Something like these https://www.harborfreight.com/mater...-casters/6-in-rubber-swivel-caster-61844.html
or these https://www.harborfreight.com/mater...sters/3-in-cast-iron-swivel-caster-58996.html
would likely be much better.

Or a heavy duty version of these might work.
1000013521.jpg
 
Those small casters scare me. I'd be more concerned with upgrading them before strengthening the floor.

Something like these https://www.harborfreight.com/mater...-casters/6-in-rubber-swivel-caster-61844.html
or these https://www.harborfreight.com/mater...sters/3-in-cast-iron-swivel-caster-58996.html
would likely be much better.

Or a heavy duty version of these might work.
View attachment 280127
Those are nice but have a higher "point load" than the casters, unless you use a lot of them. Large diameter and wide rollers would spread the load better.
 
Are the dry contacts configurable somewhere? I can't find it in the EW software.
I haven't gone down that rabbit hole I just got done getting it back together The Wi-Fi's -50 versus -72 which is a massive DB increase. This is someone it rarely uses the Wi-Fi in Bluetooth..

Had I have known what I just went through it might have been easier just to move the antenna...

Well I got one BMS replacement under my belt wasn't too bad once you came up with a game plan.

I haven't really looked at the contacts yet there are functions you can turn on I know one function reduces the LED count or the top two won't light up. So it just be one of those trial and error or we can ask Bill.
 
Well there is a LCD port on the BMS I couldn't resist I had the wire so I brought it off the faceplate for future use. I've gone down the rabbit hole with this one so as we'll keep having fun.
 

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Does anyone know if over CAN bus the Max Discharge Current goes to 0 when the discharge FETS turn off?

Edit: For Pylon protocol.
 
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Does anyone know if over CAN bus the Max Discharge Current goes to 0 when the discharge FETS turn off?

Edit: For Pylon protocol.
CAN BUS reports the current condition no mater what it is until the BMS turns off. There is a timer that counts down so after a few days of inactivity the BMS may shut down. No current going in or out it goes to sleep.
 
CAN BUS reports the current condition no mater what it is until the BMS turns off. There is a timer that counts down so after a few days of inactivity the BMS may shut down. No current going in or out it goes to sleep.
I am trying to detect over CAN with my control system when all batteries are depleted (discharge FETs off). Preferably I could use the dry contacts if I could configure them (assuming that contact would be change either way in that case and would be more immediate then waiting for a CAN frame), but for now CAN will have to work (I hope).
 
For a PACE BMS:
Dry contact 1-PIN1 to PIN2: normally open, closed during fault and protection;
Dry contact 2-PIN3 to PIN4: Normally open, low battery alarm closed.
 

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