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Valence U27-12XP in Parallel?

Tycoon

New Member
Joined
Sep 20, 2019
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7
William,

Thanks to your videos I've learned a lot in the past couple months.

I'm building a system for my future RV. Currently I've got a 100w x3 solar panels, Lifepo4 compatible MPPT, and 1000w pure sine wave inverter. I imagine I will make some adjustments once I get the RV.

My question is, should I have any other components besides the "Victron BatteryProtect (Smart 12/24V-220A)" to manage my battery bank? I've got x4 Valence U27-12XP batteries. I'm planning on running in Parallel 12v because in series they require their own BMS which i'm not able to find anywhere.

I'll eventually look at doing a Lifepo4 charger for when connected via shore power. Right now I've got a few standard smart chargers for temporary clamp charging.

Any recommendations?

Bobby
 
Hi Bobby. I have 4 of the Valence batteries currently hooked up to 4 battery balancer's I purchased from Electric Car Parts Company. They were 23.50 per battery and keep my bank to within 1/100 of a volt usually. I seen it once at 2/100 of a volt out once. I am looking at the same battery protect as you and I think if we cover those bases, we should be able to connect them however we want. There is a member on here that has the Valence software and links to some cables that should let us read all the battery information. I need to contact him for the software because I cannot find it myself. I have not hooked my batteries up together yet, just tested capacity and balanced them. Waiting for the protect and some cables. I currently have no plans to get the BMS and I am going to connect them series parallel. Hook up the parallel batteries first if doing this.
 
Hi Bobby. I have 4 of the Valence batteries currently hooked up to 4 battery balancer's I purchased from Electric Car Parts Company. They were 23.50 per battery and keep my bank to within 1/100 of a volt usually. I seen it once at 2/100 of a volt out once. I am looking at the same battery protect as you and I think if we cover those bases, we should be able to connect them however we want. There is a member on here that has the Valence software and links to some cables that should let us read all the battery information. I need to contact him for the software because I cannot find it myself. I have not hooked my batteries up together yet, just tested capacity and balanced them. Waiting for the protect and some cables. I currently have no plans to get the BMS and I am going to connect them series parallel. Hook up the parallel batteries first if doing this.
The battery balancer idea sounds great. I just ordered 4 for my set. Thanks for the info!
 
That's great! Can't wait to get my system up and running. You should PM somewhereintheusa for the software or wait until I get it and spread it far and wide. Good luck to you and your system.
 
Hi Bobby. I have 4 of the Valence batteries currently hooked up to 4 battery balancer's I purchased from Electric Car Parts Company. They were 23.50 per battery and keep my bank to within 1/100 of a volt usually. I seen it once at 2/100 of a volt out once. I am looking at the same battery protect as you and I think if we cover those bases, we should be able to connect them however we want. There is a member on here that has the Valence software and links to some cables that should let us read all the battery information. I need to contact him for the software because I cannot find it myself. I have not hooked my batteries up together yet, just tested capacity and balanced them. Waiting for the protect and some cables. I currently have no plans to get the BMS and I am going to connect them series parallel. Hook up the parallel batteries first if doing this.
The batteries already have a built in BMS so I'm not sure why you'd add a second external one to each battery? The Valence external BMS which is not available seems to me to do the job of balancing between batteries, while the internal BMS balances the cells in each unit. I may be wrong of course...
 
You are exactly right. The Internal BMS automatically manages each battery's internals. I wish I had the external BMS from Valence but I do not but I still wanted the balance features for my bank. I'm new to Lithium and I paid a pretty penny for these batteries and want them to last. Some may say its overkill but I like looking at those green lights and know my bank is balanced. Now to get a battery protect to work correctly and I'll feel pretty confident about my setup. I have 2 other AGM banks that I use the balancers on as well. Cheers!
 
You are exactly right. The Internal BMS automatically manages each battery's internals. I wish I had the external BMS from Valence but I do not but I still wanted the balance features for my bank. I'm new to Lithium and I paid a pretty penny for these batteries and want them to last. Some may say its overkill but I like looking at those green lights and know my bank is balanced. Now to get a battery protect to work correctly and I'll feel pretty confident about my setup. I have 2 other AGM banks that I use the balancers on as well. Cheers!
I ordered 4 for my battery bank and received this email saying they’re for lead acid. I replied saying they’re lead acid drop in replacements. Waiting for a response. 9AC04C6D-2CE3-42D4-A8CE-A89026EC582C.jpeg

I’ve also found a diagram on how to wire batteries for balanced charging. Not sure if it solves the battery balance situation. I’ll attach the screen shot as well. Perhaps it’ll work? 5A842474-6A8A-449E-B91F-C82CA46E62DA.png
 
That is very strange. The instruction manual states clearly the battery types. Lifepo4 is the first one listed along with gel, lead acid etc. Perhaps the 6v and 12v version are only for lead acid and the 2v-5v for lithium? They seem to be working fine and are not hot. The manual said its safe to use with or without a BMS. I received no such email when I ordered them. They are the same model number as the balancers for 2v-5v which isolate the common rail from the cells allowing you to use them in series or parallel. QNBBM But your right, everywhere else online just says lead acid. The web page was so misleading. Anyone know a reason these may not be safe for Valence Batteries?
 
I have 2 of the Valence U27-12XP batteries and planning on hooking in parallel but had no plans on using a battery protect. Should I, and if so can you explain why? The balance of the system includes 200W solar, a 30a MPPT charge controller and a 2000w inverter (I know the inverter is too large for the storage but it's what I have).
Thanks!
 
I also purchased two of the Valence U27-12XP batteries that I would like to run in parallel. Trying to figure out if I can run these without an external BMS?
 
I have the
ISDT BattGo BG-8S Battery Meter, LCD Display Digital Battery Capacity Checker Battery Balancer Battery Tester for LiPo/Life/Li-ion/NiMH/Nicd
for Valence U27-12XP batteries, but I do not know what "cable" is needed to connect the device to the batteries.
Can anyone point me in the right direction??? Thanks in advance.
 
Where are you going to hook these up? There is already a cell balancer inside. There are also a lot of unmarked black wires coming from the battery pack that aren't easily accessible. Mine seem to be doing a good job of keeping the cells in balance. It's quite simple to build protection against charging below freezing. A good inverter/charger and solar charge controller will take care of under/over charge.
 
Hi Bobby. I have 4 of the Valence batteries currently hooked up to 4 battery balancer's I purchased from Electric Car Parts Company. They were 23.50 per battery and keep my bank to within 1/100 of a volt usually. I seen it once at 2/100 of a volt out once. I am looking at the same battery protect as you and I think if we cover those bases, we should be able to connect them however we want. There is a member on here that has the Valence software and links to some cables that should let us read all the battery information. I need to contact him for the software because I cannot find it myself. I have not hooked my batteries up together yet, just tested capacity and balanced them. Waiting for the protect and some cables. I currently have no plans to get the BMS and I am going to connect them series parallel. Hook up the parallel batteries first if doing this.
https://1drv.ms/u/s!AitN-nrl5qF0d2Lt7EMehj39EJA Here's the software. You'll need an extractor to extract the files.
 
So here is a photo of the U27-12XP, with the side cover removed. We can see the five leads for the cell balancer and the 8 heavier black leads for temperature just to the right. My question is, will this board provide cell balancing and temperature protection stand alone, not hooked up to external control system via the black pigtails? The board doesn’t look like BMS I’ve seen Will look at. I don’t see MOFFETs?
 

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So here is a photo of the U27-12XP, with the side cover removed. We can see the five leads for the cell balancer and the 8 heavier black leads for temperature just to the right. My question is, will this board provide cell balancing and temperature protection stand alone, not hooked up to external control system via the black pigtails? The board doesn’t look like BMS I’ve seen Will look at. I don’t see MOFFETs?
It is my understanding that the internal BMS WILL NOT shut down in any event.
 
I think it is more of a battery monitoring system rather than a battery management system. The internal BMS will balance the cells within the module but I don't think it will do any kind of protective disconnect, I think the external BMS is required for that or you have to build in your own failsafes into your system.
 
The batteries already have a built in BMS so I'm not sure why you'd add a second external one to each battery? The Valence external BMS which is not available seems to me to do the job of balancing between batteries, while the internal BMS balances the cells in each unit. I may be wrong of course...

I plan on using three of the U27-12XP batteries in parallel. The internal BMS should keep the individual batteries balanced. Theoretically I could moniter each battery individually to see when the batteries need to be balanced in relationship to each other correct? I could then disconnect batteries from the bank and charge each one individually to the exact same voltage. Does this plan make sense to you guys?
 
Does anyone know if I could remove the internal BMS as in the picture above and replace it with another BMS using the existing wires that are connected to the built in BMS. I would think you could remove the wires that come in from the external cables and use the remaining wires to connect another BMS. Question is, of the remaining wires (coming from inside the battery) which ones connect where on the new BMS if that's possible?
 
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