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Batrium K9/Core BMS for 16s2p Basen eve/lichen 32 cell review

Stewfish

New Member
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Oct 20, 2020
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316
Batrium is great for 16s+, 32 cell+ systems. For our large property high voltage gets you further distances with less voltage drop. 48v was my goal from day one for our ground mount system. We are fully off grid which meant we needed a lot of kwh. But how do you manage 32 cells, or even more in the future?

We chose MPP bc of a long history of working off grid in Australia for over a decade. Easy generator start/backup, all in one, etc. I got 2 6000w inverters for $2200. You can make the LV6548s do split phase 240v for normal american breaker panels or use one inverter for 120v single phase to each leg in the panel if you don't have 240v appliances. Then I have a backup inverter (our current situation). It also does 250v DC for long distances from the panels, 8000w max, plenty to charge 28kwh w one inverter. Although two would be great when I get the other 24 panels up.

BMS options for large batteries:

The Chargey BMS is great and my second choice, but it needs 4 SSRs to address heat issues and power at all ends effectively for two 16s batteries. They don't communicate between 16s batteries paralleled and the cost was going to be $850ish.

Daly are more prone to break and still has the parallel issue, but can do 16s. $175 each for 300amps out.

Overkill BMS does max 8s

Electrodaucus didn't have 16s 48v and only had 8s at the time, and wasn't setup do do 32 cells

That lead me to Batrium which doesn't have the current run through the device like Daly or Chargery. Which one do you need and what's up with all the names. I went to the site and scratched my head for 2 hours until I found the comparison video. The parts all cost too much but without all the cell monitors its a bit cheaper ang priced like the chargery but can do 32 cells together.

Basic explanations:
Mon = think cell "monitor"
Leaf mon = Nissan leaf monitors
They connect to a mini computer = watch mon
Long mons and blockmon M8s are other monitors like a leaf mon, but that attach to block type cells that have m8 posts or are long cylinders for example.

Then came the watchmon 4 " wm4" video and I knew I had what I needed, but it only did 15s. Hu? Why? WTF? Well it was to work with batteries that had 15 cells. The Chinese calb/eve/Lichen cells in 16s to make 48v hadn't gotten cheap and popular yet.

So I emailed them and the funny ladies at batrium kept me updated on a new 16s system that was in the works. I wouldnt need all the expensive monitor attachments, just balancing wires like the wm4. It became the Watchmon Core (computer) and K9 (16s monitor)

K9 and costs:
With the k9 you can do 16s and have six of those batteries. That would be 84kwh. Without all the exspenive leaf mons, long mons, etc, the price for the Core with shunt, expansion relay board, and two K9s was $850. Oh and it had a testmon which tells you if all your balance leads are setup correctly so you don't fry your bms. You can get that price down for 32 cells to about $650 without the shunt, relay expansion board.

Support:
I ran into a known MPP usb glitch that prevented me from updating the core firmware but Maxine at Batrium figured that out quickly for me. I sent her a youtube video of my setup and what I tried to do and where I got stuck. She seemed to know the issue right away.

Amazing Software:
The software has a lot of check and balances, pun intended. It has a lot of auto features to update firmware easily. There is a wizard for the setup, tool sections, etc. It's super easy and even wifi setup and remote monitoring with that wifi was a breeze like setting up a fire stick or chromecast. With the shunt I just can't get watts produced and used separately from the inverter just an average + or - going in or out of the battery. All the data was great for remote monitoring my solar shed in the house until I figured out the glitch with the MPP watchpower wifi app.

Final wish:
My wish is unrealistic - My biggest con/wish is for a dozen hours of videos explaining everything and that they were smaller videos organize by name rather than how to install "device name". Some wm4, wm5, or core videos show different settings like shunt, soc estimates at first startup, and much more.
There is just so much, like what the white light on the core means vs blue,
what all the settings in the app do,
what wavy charting of the cell voltages at high SOC means in theory
When to choose active balancing vs letting it just balance on its own all day
Basically enough to teach me

But if you watch all their videos eventually all the parts seem to be discussed somewhere in one of the videos. The help icon in the program is really good too. Also the support articles are good for learning as well. You just have to read and watch everything even non core/k9 stuff.

I'm happy, and the 32 cells look happy. Well, I'm off to bed it's late (1:13am) and I have a 1300 ft fence to start tomorrow, so pardon the grammar.

This was an interesting video for learning:
 
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I'm adding education videos for my future reference encase I need to adjust settings, esp for manual/bypass balancing settings, etc.

Here is a good video on icons in the software (temperatures), red bars, and some more discussion.



Lithium Solar is great. Like Will, he shows Ferrels etc and little helpful details when making you purchasing lists and laying out you "to do" list. This is his wm5 video similar to WMcore - atleast wiring/install wise. The core/K9 does 16s and the wm5 only does 15s.

After re watching his video it reminded me how annoying the fuses were. The wire is thin for a reason and discussed by batrium in their core or wm5 video. With the spring of the fuse holder, the tension of the spring holds the fuse in place and it spins the wire vs just the fuse housing. I just screwed on the fuse holder housings and the bolted them down to the cell so the wire was not stressed during install. It was 100% annoying, and I hated dealing with required extending of the balance leades. There is just no way around it for a ceramic/sand/DC rated type fuse. It is way safer than the typical automotive blade type fuse holders that can still transfer an arch with high voltage DC circuits and create a fire. It was the worst part about the kit, but 100% understandable. Premade wires made to say 5ft or 10ft with a blank end and seperate crimp ferrels for that end that you cut to size would have been nice and saved me an hour. However you would need the tool so then the ferrels would ussually come with a tool, so it all makes sense they don't make these leads. Each install differs so where do you draw the line on custom, vs cost, vs options, vs whats available to buy and sell during this covid era. I appreciate the fuse holders even tho it sucked to extend the wires for an hour.

Note: I used adhesive lined heat shrink butt connectors so the adhesive would grab the wire vs the majority of the stress being placed on the wire crimp it's self. If you have ever had to heat shrink anything and redo it later for some reason, then you known the heat shrink slides off easily. It may create a strain relief for bending at the end, but def not for pullinon anything but the copper strands. For best case do the adhesive butt connectors and then heat shrink past the end.of the connector for bending strain relief. Nasa uses harnesses in their wiring for a reason. Butt connectors or connectors for any matter create a weak breaking point with any vibration e.g. RV driving. So make a "harness" with heat shrink esp over any connectors. inhave manynsizes of adhesive lined heat shrink. It's 100% better for a boat so why not an RV or anything else for that matter if it's a couple dollars more on amazon. Always use dielectric grease to prevent corrosion, including galvanic corrosion from copper terminals to stainless bolts on the battery, tinned terminals are better also with the grease. A cherry sized glob of dielectric grease over battery "end" terminals has lasted for 4 years (life of a marine battery) in a saltwater environment on every boat I have owned. I have saved man stranded boaters in florida that couldn't start their boats. The first thing l do is look for corrosion at their battery and clean it up. 90% of the time this is the issue. I read many articles from nasa, to boat builders about the subject before I got into solar and thisnis. Warning from.me that travels over to solar/batteries/connectors/wiring. So spend $8 and get a tube of permatex dielectric grease and keep that oxygen out of your connections. Home depot brand/supplier is thinner and will run down bs staying ina glob around the terminal.

 
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I know they are super busy. Popularity, and probably staffing issues with covid prevent a lot of content, etc. I honestly have nothing bad to say, just a wish list from a noob with normal noob expextations. I hope this helps them- This video should be edited and many things added to the new core video. It has many amazing details on the software including -

1.)how to turn off the password request you have to input all the time. If you are off grid then you are acres/km away from neighbors or someone trying to login into your stuff. Other newer core videos don't have this detail. I had to find this video again after getting annoyed with the password requests after a few days of upgrades, and adjustments.

2.) Details on wifi setup and the directions to change from USB communication to just usb power with wifi communication. Some devices need a specific usb connect/disconnect sequence.
Note: I would have installed the driver 100% before inserting the usb cable. I have seen way too.manymissues with that scenario. It must be good programming ;)

3.) Temp senor locations, where to put the 4 sensors. A manual didn't xome with the kit so when the time came Iwas scratching my head.

4.) Shunt and possible fan options. So far its the best video I have found on Batrium. Although I have not watched older videos.

5.) A huge setting is the bypass balance ( I think of it as manual "high" balance mode or "top balance mode"). This video shows how to engage that.

6.) The relay disconnect circuit breaker is also an amazing function and safety device. The only issue I see is with the breaker device is the size of the wire it can use. I was able to get a really good deal on for a welding wire from a amazon kit that was only 10 ft leads. It was cheaper than many other sizes that were available. I think because many welders ise 4/0 wire atb 10 ft, and not exceeding 10 ft to get good penetration (I'm and intermediate farm welder). I recall watching welding videos years ago decades after high school welding were it was discussed length for leads. So having a low cost for a large wire but a breaker that looks to only take 2 gauge awg wire, you limit the amps. I have two 6000w inverters, so why not use 4/0 awg if the inverter can accept that wire ;) You'll have to do a voltage drop calculation in a voltage drop calculator to see if the distance and wire gauge works for your situation. I still feel this is an amazing detail they teach you.

This video addresses many questions I was wondering about and making educated assumptions about when installing the core/K9.

New videos need to encompass many other things including fan software triggers, etc. Batrium really needs to edit old missing/lost videos clips into newer videos and any videos in the future. Just have a 30 minute video you edit and add to the end of every video with all the details of the software ;)

There needs to be a top balance button:
I can't overstate this possible option enough. I had a .15 cell variation from high to low and within 20 minutes of setting the bypass to 3.2v like they did in the video the battery was top balanced at (90% soc...) to a variation between cells of .04 . To me that just seems way safer than .15 and the possibly of burning up a cell down the road. There needs to be a top balance or emergency bypass balance button. I'm amazed at how well the bypass voltage setting worked. I have had a lot of anxiety on my new battery and the high soc cell variation. .15 variation is a lot. The button should auto bypass for cell deviation or variation, esp at 90% or above = top balancing. I say 90% bc why not follow longlife/battle borns' bulk charge parameter that would be basically 90% soc.

Watchmon core w/ the K9 is the new 16s upgraded version of the watchmon5 which was just 15s.
 
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Batrium is great for 16s+, 32 cell+ systems. For our large property high voltage gets you further distances with less voltage drop. 48v was my goal from day one for our ground mount system. We are fully off grid which meant we needed a lot of kwh. But how do you manage 32 cells, or even more in the future?

We chose MPP bc of a long history of working off grid in Australia for over a decade. Easy generator start/backup, all in one, etc. I got 2 6000w inverters for $2200. You can make the LV6548s do split phase 240v for normal american breaker panels or use one inverter for 120v single phase to each leg in the panel if you don't have 240v appliances. Then I have a backup inverter (our current situation). It also does 250v DC for long distances from the panels, 8000w max, plenty to charge 28kwh w one inverter. Although two would be great when I get the other 24 panels up.

BMS options for large batteries:

The Chargey BMS is great and my second choice, but it needs 4 SSRs to address heat issues and power at all ends effectively for two 16s batteries. They don't communicate between 16s batteries paralleled and the cost was going to be $850ish.

Daly are more prone to break and still has the parallel issue, but can do 16s. $175 each for 300amps out.

Overkill BMS does max 8s

Electrodaucus didn't have 16s 48v and only had 8s at the time, and wasn't setup do do 32 cells

That lead me to Batrium which doesn't have the current run through the device like Daly or Chargery. Which one do you need and what's up with all the names. I went to the site and scratched my head for 2 hours until I found the comparison video. The parts all cost too much but without all the cell monitors its a bit cheaper ang priced like the chargery but can do 32 cells together.

Basic explanations:
Mon = think cell "monitor"
Leaf mon = Nissan leaf monitors
They connect to a mini computer = watch mon
Long mons and blockmon M8s are other monitors like a leaf mon, but that attach to block type cells that have m8 posts or are long cylinders for example.

Then came the watchmon 4 " wm4" video and I knew I had what I needed, but it only did 15s. Hu? Why? WTF? Well it was to work with batteries that had 15 cells. The Chinese calb/eve/Lichen cells in 16s to make 48v hadn't gotten cheap and popular yet.

So I emailed them and the funny ladies at batrium kept me updated on a new 16s system that was in the works. I wouldnt need all the expensive monitor attachments, just balancing wires like the wm4. It became the Watchmon Core (computer) and K9 (16s monitor)

K9 and costs:
With the k9 you can do 16s and have six of those batteries. That would be 84kwh. Without all the exspenive leaf mons, long mons, etc, the price for the Core with shunt, expansion relay board, and two K9s was $850. Oh and it had a testmon which tells you if all your balance leads are setup correctly so you don't fry your bms. You can get that price down for 32 cells to about $650 without the shunt, relay expansion board.

Support:
I ran into a known MPP usb glitch that prevented me from updating the core firmware but Maxine at Batrium figured that out quickly for me. I sent her a youtube video of my setup and what I tried to do and where I got stuck. She seemed to know the issue right away.

Amazing Software:
The software has a lot of check and balances, pun intended. It has a lot of auto features to update firmware easily. There is a wizard for the setup, tool sections, etc. It's super easy and even wifi setup and remote monitoring with that wifi was a breeze like setting up a fire stick or chromecast. With the shunt I just can't get watts produced and used separately from the inverter just an average + or - going in or out of the battery. All the data was great for remote monitoring my solar shed in the house until I figured out the glitch with the MPP watchpower wifi app.

Final wish:
My wish is unrealistic - My biggest con/wish is for a dozen hours of videos explaining everything and that they were smaller videos organize by name rather than how to install "device name". Some wm4, wm5, or core videos show different settings like shunt, soc estimates at first startup, and much more.
There is just so much, like what the white light on the core means vs blue,
what all the settings in the app do,
what wavy charting of the cell voltages at high SOC means in theory
When to choose active balancing vs letting it just balance on its own all day
Basically enough to teach me

But if you watch all their videos eventually all the parts seem to be discussed somewhere in one of the videos. The help icon in the program is really good too. Also the support articles are good for learning as well. You just have to read and watch everything even non core/k9 stuff.

I'm happy, and the 32 cells look happy. Well, I'm off to bed it's late (1:13am) and I have a 1300 ft fence to start tomorrow, so pardon the grammar.

This was an interesting video for learning:


Oops I can't edit the original post now. Note: It's the wm5 that's similar to the k9 setup not the wm4. The wm4 needs the leaf mon/longmon/block mons

On that note. I left out the price on the OP. You can get the core/k9 bare bones for $450 US for 16s. With a few burnt up Daly BMSs it would pay for itself.
 
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I would really like to buy Australian made. I have looked on the Batrium website and just overwhelmed by the various names of products. I have contacted them and there was no simple answer which is quite disappointing. I'll have a look through the videos posted when i have time. I'm looking at making a few 8s packs using 280ah EVE cells. For me reliability is key.
How are you disconnecting charge and loads if a fault occurs?
 
I would really like to buy Australian made. I have looked on the Batrium website and just overwhelmed by the various names of products. I have contacted them and there was no simple answer which is quite disappointing. I'll have a look through the videos posted when i have time. I'm looking at making a few 8s packs using 280ah EVE cells. For me reliability is key.
How are you disconnecting charge and loads if a fault occurs?

The last video shows how a breaker off the shunt that can be tripped for various faults.

I think you basically have two choices for the new system. The core runs it all and is the new wm3/4/5. So choice one is k9 or choice two connect long mons or block mons to the cells. They are more cost tho. I had to do the k9 bc my system was 16s2p. With 8s you can do more options. The k9 vs block mon balancing amount seems to be the main thing that comes to mind that you should look into. The blockmons /long mons connect to the core to balance the cells just like the k9. The k9 uses balance leads and a heat sinks. They both bleed powerful people from high cells into heat as the lower cells charge up and balance. The block/long mons act as heat sinks from what I gathered. The blockmons bolt on top of the cells, the long mons have leads that connect to the cells also.

Couple things to really think about. Higher voltage means
1.)Smaller wire
2.) Charge controllers can produce more watts at 48v vs 24v so you can use cheaper/smaller controllers
3.) Two parralleled 8s batteries is not a stable and is more expensive BMS vs one 16s.
 
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The last video shows how a breaker off the shunt that can be tripped for various faults.

I think you basically have two choices for the new system. The core runs it all and is the new wm3/4/5. So choice one is k9 or choice two connect long mons or block mons to the cells. They are more cost tho. I had to do the k9 bc my system was 16s2p. With 8s you can do more options. The k9 vs block mon balancing amount seems to be the main thing that comes to mind that you should look into. The blockmons /long mons connect to the core to balance the cells just like the k9. The k9 uses balance leads and a heat sinks. They both bleed powerful people from high cells into heat as the lower cells charge up and balance. The block/long mons act as heat sinks from what I gathered. The blockmons bolt on top of the cells, the long mons have leads that connect to the cells also.

Couple things to really think about. Higher voltage means
1.)Smaller wire
2.) Charge controllers can produce more watts at 48v vs 24v so you can use cheaper/smaller controllers
3.) Two parralleled 8s batteries is not a stable and is more expensive BMS vs one 16s.
Thanks,

At the moment my SMA inverter is still working fine so will stick with 24v. Its a big investment to change inverters.
 
I dont think any other BMS will balance your parallel batteries, thats why I did Batrium.
Def stick with your 24v inverter and just keep adding 8s packs. One k9 and core will get you up and running for $450. Add a shunt and test mon for a little more.

Then you just need individual K9s in the future everytime you want to add another 8 cells with max 16s cells per k9, for a total of six K9s.
 
I've been researching Batrium and was just confused as ever, 14S, 15S, what the heck and Longmon's plus all kinds of things. And everyone was using 18650 cells.

Finally, I ran across this video and it made much more sense and it uses prismatic cells. As for the fuse holders, can't he just buy new terminals?

 
I would really like to buy Australian made. I have looked on the Batrium website and just overwhelmed by the various names of products. I have contacted them and there was no simple answer which is quite disappointing. I'll have a look through the videos posted when i have time. I'm looking at making a few 8s packs using 280ah EVE cells. For me reliability is key.
How are you disconnecting charge and loads if a fault occurs?
Only spent 15 seconds on their website. I wished they had quick definition on their landing page. Mons here mons there gave me nose bleed. However, i'm starting to understand the benefits of batrium and thanks to this forum. I'm seriously looking into it more.
 
Only spent 15 seconds on their website. I wished they had quick definition on their landing page. Mons here mons there gave me nose bleed. However, i'm starting to understand the benefits of batrium and thanks to this forum. I'm seriously looking into it more.
I was confused as you were, but then discovered the K9. This makes it much easier. https://www.batrium.com/products/watchmon-core-k9

I'm building a few 48V battery packs with LFP prismatic cells. This is what I would need minimum is one Watchmon CORE and one K9. If you build it as 2P16S, then that's all you need. Personally, I prefer individual cell monitoring, plus, if I was to shut off one pack for repairs or maintenance, then I would want one Watchmon CORE and two K9's .

You of course need a shunt plus the fuse holders and you will have to source a shunt trip breaker. The shunt trip breakers aren't cheap. With a 48V system, I will also have to source a 48VDC to 24VDC converter for the shunt trip breaker shunt trip as those are 24VDC.

The K9 makes this quite easy for prismatic cells. No Blockmons, Longmons. Less expense and easier setup. These looks to be a nice unit.
 
I would really like to buy Australian made. I have looked on the Batrium website and just overwhelmed by the various names of products. I have contacted them and there was no simple answer which is quite disappointing. I'll have a look through the videos posted when i have time. I'm looking at making a few 8s packs using 280ah EVE cells. For me reliability is key.
How are you disconnecting charge and loads if a fault occurs?
Same experience here.
 
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