M star mppt 45 suitability on valence lithium cells?

jimbob01

Im running these : valence u27 xp 12 ....
I have 8 cells wired in at 24v  4x 2 cells.
My concern is that of overcharging through the solar ....ie i cant seem to find how to limit the current / voltage accurately on the m star mppt 45s?
Do i need to hook it up to a computer? 
Its not too much of an issue here in the UK at wintertime...
Summertime is my concern...
These are 130 ah 12v cells... lightly used and just put back in to service...

mcgivor

According to the specifications they can be charged with charge controllers with an AGM algorithm which may, or may not, be exactly what is required, hense the, can be charged with "MOST' disclaimer. Custom settings using a computer will enable more precise control of the parameters, however 45A maximum is on the low side of the recommended charge current for one battery, let alone four, but that figure really depends on discharge rates between charging cycles. It would appear that they are intended as a drop in replacement for lead acid each with it's own BMS, which is theoretically a good feature but the technology is reletivaly new, and I'm no expert, there are however others on the forum who are  more experienced and may provide more insight. I too am eager to read responses as I'm looking at future replacements for LA technology.

jimbob01

I have a pair of 45 amp mppts mstar...a 60 amp pwm set to cut out b4 the mppts
I get 3kw of solar in the summer and i just was looking for the simplest method of limiting the end current / voltage going in to these batteries as in summer they will be full  quite early in the day...
I have these from  low mileage decommissioned electric vans.. i have enough to make another bank on a reserve switch... and some left over.

jimbob01

Basically im getting 120- 130 amp @24v on a sunny day incoming.

BB.

Jim,

Just to be clear, those are kWatt*Hours and Amp*Hours? (missing the *Hours part?)

-Bill

jimbob01

Yes the batteries i have are 1.7 kwh each 130 ah and 12v. Jim

jimbob01

I May have not been clear: 3kw is my solar array
My bank is 8x 12v batteries wired as 4 x 24v @ 130ah
Giving 520ah @24v
Batteries are valence u27  12 xp lightly used cells
My concern is setting up the charging correctly ie end amps etc ? Hvd? Lvd?
I have 2 x mstar 45amp mppts
1 xantrex c60 pwm
1 outback 3kw inverter/Charger 

karrak

Do you have the Valence BMS that goes with those batteries?

Simon

mike95490

You need to use the MSView software and a serial cable to connect a windows PC to the controller.  You can then set any voltage and current limits you desire.  Converting a PC USB port to a Serial cable (with a valid power signal) is hard, only one company is known to do it properly   Tripp Lite  model U209-000-R USB -Serial  https://www.tripplite.com/usb-serial-adapter-cable-usb-a-db9-male-male-5-ft~U209000R/
MS references this specific model as having the proper DC-DC converter chip inside to power the RS232 circuits

You may find these links helpful
https://www.morningstarcorp.com/morningstar-best-practices-battery-chemistry/   using MS View (it also has latest firmware for controllers in the download archive, update the controller firmware first, then adjust things. READ the instructions or you will BRICK things)
https://senormisterioso.wordpress.com/2017/09/22/programming-a-morningstar-ts-45-to-work-with-battle-born-lipo4-batteries/

jimbob01

Simon:No i dont have valences own external bms....
Thanks mike ive ordered the cable so hopefully i can set up my charger

karrak

The reason I asked was that it looks like Valence uses their own proprietary BMS. I would think that the battery balancing and cell monitoring  part of the BMS is contained within the batteries you have. Each individual battery BMS is connected to other individual battery BMS's and to a central control unit via a proprietary interface.

This statement from their website
"Our battery modules are energy storage devices that can be configured in a variety of ways to meet the particular requirements of an application. To do so requires a properly configured Valence Battery Management System (BMS) for the system parameters and contactors. Generic or non-Valence BMS units are not suitable for use with Valence batteries. For safety reasoning, configuring of a Valence BMS needs to be performed by Valence or its authorized reseller. We do not support Valence products that have not been purchased directly from Valence or through an approved reseller."

and the lack of detailed information about their BMS on the website make me think that you wont get much help from them to get the BMS in the batteries working properly.


What are your plans to implement the two important functions performed by the BMS

1. Keeping the individual cells in the individual batteries balanced and the batteries balanced relative to each other.
   
2. Making sure that the cells are kept within their safe operating voltage,temperature and current zones.

Simon

jimbob01

Hi simon thanks for raising those points...ive just managed to get hold of the valence software which apparently opens communications.. i need a converter cable which im in the progress of sorting out to enable connection from pc to battery...im unsure of the best way to progress in terms of bms... i was looking at the batrium system which seems to be in use by some folks using these cells ...
What is the point of an internal bms if it does nothing?
Is it just if the battery is in single use application?
Any ideas greatly appreciated?Thanks James

karrak

Do the battery BMSs communicate directly with the PC software or do you need the Valence U-BMS as well?

I would be interested in any links to information on people using these batteries for DIY.

Have you seen this Youtube video that documents removing the BMS supplied with the battery and installing a Batrium BMS instead? If you can't get the Valence BMS working this is probably the best way to go. Other BMSs that you could look at in place of the Batrium BMS are the Orion Jr and the unit from Zeva Australia 

Internal BMSs come in several flavours.

• Fully self contained: where all the circuitry necessary to balance the individual cells and disconnect the battery from the outside world if there is a fault is within the battery case. These batteries are marketed as drop in replacements.
• Self contained but need external circuitry to stop charging or discharging: Same as fully self contained but need to connect to external circuitry or to the charger or load to stop them or disconnect them in the event of fault.
• Master/Slave configurations: Where there is some of the BMS circuitry within the battery that talks to a master controller outside

It is possible that the balancing circuitry within the Valence batteries you have will be able to balance the battery autonomously however this is only the case if the balancing circuitry works by removing charge from the individual cells by placing a load (usually a resistor) across the cell. This is known as passive balancing. The other form of balancing is called active balancing and works by moving charge from one cell to adjacent cells. If the Valence battery uses active balancing the batteries have to be daisy chained together to allow the transfer of charge from one battery to the next.

Simon

jimbob01

Hi simon...thanks for your detailed reply.... ive yet to get the software open due to the pc (software only runs on xp) needing updates and cleaning.... also i have to go to a wifi connection... it doesnt seem to pick up the phone signal from my android hotspot....i believe the battery bms communicates directly with the software (which im happy to share) ... as the guy who i bought the batteries off was able to show me cycles logged and other info on the pc once connected.
Yes i saw the batrium route conversion video...thanks for that... i haven't looked in to the other ones but i shall...
Many thanks James

jimbob01

Hi simon....ive now got the software up and running and it initiates an active balance at the top end ie when the voltage is 14.6 ...
As far as i can see

Zach

jimbob01 said:

Hi simon...thanks for your detailed reply.... ive yet to get the software open due to the pc (software only runs on xp) needing updates and cleaning.... also i have to go to a wifi connection... it doesnt seem to pick up the phone signal from my android hotspot....i believe the battery bms communicates directly with the software (which im happy to share) ... as the guy who i bought the batteries off was able to show me cycles logged and other info on the pc once connected.
Yes i saw the batrium route conversion video...thanks for that... i haven't looked in to the other ones but i shall...
Many thanks James

Hi James,

I'm in a similar position, hoping to be able to communicate to the internal BMS of some Valence U27-12XP batteries. Would you be willing to share how you got the software, and what the physical interface was like on the battery? I'm struggling to find that information online.

Thanks!
Zach

Zeta

Zach said:

jimbob01 said:

Hi simon...thanks for your detailed reply.... ive yet to get the software open due to the pc (software only runs on xp) needing updates and cleaning.... also i have to go to a wifi connection... it doesnt seem to pick up the phone signal from my android hotspot....i believe the battery bms communicates directly with the software (which im happy to share) ... as the guy who i bought the batteries off was able to show me cycles logged and other info on the pc once connected.
Yes i saw the batrium route conversion video...thanks for that... i haven't looked in to the other ones but i shall...
Many thanks James

Hi James,

I'm in a similar position, hoping to be able to communicate to the internal BMS of some Valence U27-12XP batteries. Would you be willing to share how you got the software, and what the physical interface was like on the battery? I'm struggling to find that information online.

Thanks!
Zach


Hi Zach,
I'm wondering if you made any progress with your batteries! Would love to know. I'm planning on getting the batteries and I'm looking for the software too. Called Valence about the BMS but they have not emailed with where to get the correct BMS for the system I'm building. would love to know your thoughts!
-Lee

benhenkel

Has anyone here had success with a DIY BMS system for the valence ucharge u 27's?  Thanks