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Portable Victron Power Station operational

McMaster Carr can be a very helpful site. My mechanic introduced it to me. Good quality, and seems to have things you can't find anywhere else.
 
Putting together wire harness for BMS today. Wire for BMS power lines is scheduled for delivery later in the day. The JK active BMS is the one I have selected. I will be adding wire and lugs for final attachment.

Trying to make progress while handling other duties of life. Still looking forward to additional purchases after the first of the year.
 
Initial BMS wire attachment has been completed. Anyone who has built their own battery knows the drill. For those who are new to this, a thread helps discuss the procedure:

 
Still need to torque the screws down. This battery box has raceways to handle the initial BMS wires. I will likely bundle them together inside the box. Also I did end up trimming the rubber facing on the bottom of each bus bar to ensure a solid connection with each battery cell.

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Also wanted to point out that the battery case also comes with dividers for under, around and between the cells. There is also a "wall" that can be snugged against the battery cells to firm them in place.

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When I first went to place my order, I had picked the single welded studs for the battery cells. Amy shifted me to the updated double hole terminals. I am really glad she did.

As anyone who has worked with these cells can tell you, these terminals are robust. The initial CATL cells I have use the welded stud contacts. The surface contact area for the bus bar is scant compared to these cells.

The flexible bus bars help ensure a solid connection for both screws.
 
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After working with this battery box I find myself doing a rethink of my other system.

I was able to fabricate custom cases for these batteries. They work fine. The challenge is that they are all on one cart. Pulling it out if needed for maintenance could be a challenge.

I am playing with the idea of redoing these and placing them in the updated battery case. I would place each one on wheels so it could be moved as needed for maintenance.

This could also open up a little more space on the back wall in case I wanted to move things around since they would be closer to the ground. The batteries would be also be better protected from dust and debris.

An added bonus would be that they would integrate the BMS inside the case.
 
I'm not sure of your location and the conditions where you keep your batteries.
Note that even as little as 1C temp difference between the battery packs WILL affect their charging & discharging. While 1C isn't much is does have an effect, once you see 3 or 4 C difference it really becomes pronounced.

My powerhouse is heated & kept at 15C/60F during winter.
I had my packs on a shelf system, the pack closest to the floor was obviously the coolest with the one at the top being the warmest. There was roughly 3.0C difference between the Top & Bottom packs and both charging & discharging were slightly different with the warmer packs behaving better. It wasn't really significant BUT it was there and showed the capacity on the cooler packs was a bit less. Again, this was not significant enough to be a problem but certainly a quirk to be aware of. I switched to one wide shelf with all packs on it at 40" high off the floor and now there is never more than 1.0C temp difference between the packs and they all perform fairly uniformly... Keep in mind that at present I am running with 2x174AH, 1x105AH, 3x280AH... My Final build (now in process) will have only 6x280AH as I am donating the 2x174's to an emergency installation and the 105 is going to the toolshed system.
 
There was roughly 3.0C difference between the Top & Bottom packs and both charging & discharging were slightly different with the warmer packs behaving better.
Excellent consideration. This is the reason I initially elected to keep the batteries in my other build at the same height. The temperature is controlled and maintains a fairly consistent level year round. The update I am considering would still keep my batteries at the same elevation.
 
I initially didn't think it to be an issue but oddities made me look and then run a series of tests to see what was really going on. I found it particularly odd because the Powerhouse was designed for my climate zone... It has a Frost Protected Slab Foundation (wrapped in R20 Foam), the walls have 4" Thick HD-EPS Foam + 1" foam Thermal Break and the roof is 6" of PolyISO Foam + 1" Thermal break as well, so the structure holds the heat extremely well, even when it is -30C/-22F outside.

In the summer, the Powerhouse does not gain heat like other structures due to the Thermally Broken construction and it hasn't gotten over 29C/84F even when it was 40C/104F outside. The battery packs are quite happy at these temps and take charge beautifully. As a test during a particular gnarly heat wave, I opened the powerhouse up to allow it to take the heat in and it reached 37C/98F and again saw the beginnings of deviation within the packs were the "runner" cells started running a bit but because of my settings no triggers to cutoff but darned close...

The Powerhouse was the preliminary proof of concept before I built my home with even more insulation and has been a valuable "Test Mule" structure and great for my solar system.
 
Here is a link to the specs for the new version of JK with Inverter Support. They have built-in precharge and current limiting +.
Just highlight the model and select it, then scroll down to see the different specs.

BTW, My current packs all have JKBMS (previous version) and no precharge, but with 6 packs online, the capacitor demand isn't an issue...
It says it supports parallel connection, does that mean the BMS can communicate with another Battery BMS and sync?

Also, can this BMS be used as a regular BMS without the use of the Inverter communication feature?

Thanks.
 
It says it supports parallel connection, does that mean the BMS can communicate with another Battery BMS and sync?

Also, can this BMS be used as a regular BMS without the use of the Inverter communication feature?

Thanks.
yes on both counts BUT the folks at HankZor (the usuals who deal with JK) have gone a bit dumb "again" and JiKong itself is not terribly helpful either. None of which is a good thing IMO. There are issues presently with the latest models so I am holding my shipment till December by which time the issues should be resolved. Fortunately I have other avenues of information but those are behind NDA's so I can't get into it.
 
yes on both counts BUT the folks at HankZor (the usuals who deal with JK) have gone a bit dumb "again" and JiKong itself is not terribly helpful either. None of which is a good thing IMO. There are issues presently with the latest models so I am holding my shipment till December by which time the issues should be resolved. Fortunately I have other avenues of information but those are behind NDA's so I can't get into it.
Wow!
I had an impression JK probably had the best BMS back when I was looking for my first one but dang, with this, they'll be in their own league as long they make it work. Kudos.

Let's wait and see, very exciting.

Thanks for the info, Much obliged.
 
Well I had a chance to borrow my mechanics high end torque wrench. Sadly its lowest setting was above 6 nm. Considering the stories of snapped screws on battery cells I elected to use a torque screwdriver that has been recommended by others. It is not digital but has a fairly easy scale for adjustments. I really liked that it came with a 1/4 to socket adapter. This made tightening up the screws on the terminals much easier. I went shy of 6 nm. They are still quite snug and should be fine.

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On another thread it was recommended to place a non corrosive coating on the copper bus bar. I searched the site and this appears to be a consideration in marine or higher humidity areas. Most of the time this unit will be in a climate controlled area. Since there is an opportunity that it could be used outdoors I did place a very fine film of No-Ox-ID on the side facing the terminal. Recommendations from others are to use a very fine film and to stay away from the screws since this can affect torque settings.

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Anyone who has been on this journey can understand this. One tends to pick up little odds and ends that can be helpful from time to time. I found these a while back while working on something else. They are velcro based zip ties. They are a little wider so should be gentle enough to help secure and organize the BMS wires that always seem to be "hanging around" after a build. I elect not to trim mine since I personally like to keep them the same length.

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Anyone who has been on this journey can understand this. One tends to pick up little odds and ends that can be helpful from time to time. I found these a while back while working on something else. They are velcro based zip ties. They are a little wider so should be gentle enough to help secure and organize the BMS wires that always seem to be "hanging around" after a build. I elect not to trim mine since I personally like to keep them the same length.

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Those are nice for systems that are reconfigured often.
I've used them a few times.
 
Small update. Got Bms ready. Was a delay because the battery lugs were the narrower instead of wide lugs. Wanted a better contact area with the battery.
 
There has been a lot of discussion on battery orientation. Currently I will be positioning my batteries upright. The neat thing about this hand truck is that it has a tongue which extends out to hold larger items. After I did my measurements I realized that it would be extending out an additional 10 inches which really isn't needed. As I looked at it more I realized that there are two bolts which hold the hinge bracket. Doing some quick measurements I realized that 2 inch angle should allow me to connect a holding case to these bolts. This has been placed on order. I selected aluminum extracted 6061-T6. According to one source it has a yield strength of 35,000 psi and shear strength of 30,000 psi which may not exactly apply to what I selected, however unless I'm mistaken should be more than adequate while helping to keep things lighter. I am looking at constructing a holding case. The back wall attached to the angle is currently slated to be a 2x6. I debated the side wall materials. A 2x6 would allow better lateral support. An online calculator suggested that making the two side panels out of 2x6 vs 2x4 would add about 2.5 lbs. I am considering 1.5 angle along the bottom edges of both side 2x6s although I might decide to utilize a 2x2 instead. Either would add additional support and hold the 3/4 plywood currently slated for the floor of the box. Again, this is still a work in process so the design concept is still subject to change. Most of these materials are already on hand from other projects. Can't tell you how many variations have already been considered. I want to place padding between the battery case and the wooded box. I still have the packing foam which originally came with the batteries and battery case. This is the top consideration. A second material considered was foam pipe insulation such as provided at the big box stores.

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Keep It Sweet & Simple
Wise advice indeed. I much admit, I found myself playing with need to have versus want to have. This morning I reviewed the setting where this is to be installed. I still plan on pursuing Victron for redundancy as indicated above, however I will be scaling back on some of the things I was considering due to space.

Have decided on a box configuration. It will be simple in nature and I have most of the materials already. Hope to provide some updated photos in the next week or two. Busy schedule ahead.
 
Here are two photos showing the battery attached. The first photo shows the metal bracket attached to the carrying box. The second shows the battery in the box.

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Did you order your multi 2 yet? Current Connected mentioned in a post the other day that there's a price cut on them and the quattros, around ~$100-$200 on the smaller 3-5kVA units.
 

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