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LG Chem Batteries from Battery Hookup. 5.94 KWh

Here is the page from Ali Express


Several vendors carry the same boards. This one had fairly quick free delivery. They were also very responsive to messages.

The casing has changed and the caps are now enclosed in the cast housing. They did not have the 200 amp in stock and it had to be built, so it took over 2 weeks before it shipped. Once it did ship, I had it in 4 days.

The setup is quite easy, but there are two things that had me confused at first. Once I got it all connected, it would not turn on and just sat there. It turns out you need to supply a charging current that will push about 5 volts higher than the battery voltage. My test pack was near full charge and so the difference with a CC/CV charger was only 1 volt. I had to use a separate power supply to get it to wake up. The next thing I figured out was that once you make a setup change, like the number of cells, you have to do a full shut down and power it up again with the over 5 volt kick again. Once it is in my solar bank, this should not be a problem, but it was a bit confusing with the poor instructions. The 200 amp version has 2 amps of balance current. It is a true active energy balance system. On the app, you can watch it pull 2 amps from the cell with the highest voltage, and then push 2 amps into the cell with the lowest voltage. The two large caps are actually 35 farad super caps to hold the energy it is moving. My pack was already pretty close to balanced, so it only cycled for about an hour and now all 14 cell groups are within 0.003 volts so the balancing section is basically shut down. If any cell goes more than 0.005 out of balance it will start up again. You can also set the balance threshold as well as reduce the balance current if 2 amps is too much.

The one concern I do have is the cables are just two #7 AWG. That seems a bit light for a 200 amp rating. The charge current from the Schneider XW can hit 140 amps, and at full constant load, it could draw 140 amps, and surge to well over 200. I do not plan to run it that hard, but I don't want 4 inches of wire to be the limiter.
 
As I have been closely monitoring my LG Bolt batteries, I decided to make a few measurements. I am not stressing them at all yet. All of these values are being taken from the Schneider XW-Pro battery summary graphs, and the measured volts are inside the inverter, so all losses are included.

I am charging at under 26 amps and discharging at under 33 amps. This is all less than 0.1C on my total 360 amp hour pack. When the batteries go from resting for an hour to discharging at 28.3 amps, the battery dropped from 57.47 volts, to 57.17 volts. So a drop of 0.3 volts at 28.3 amps = 10.6 milliohms. But remember, this is at the inverter input. So it goes from 14 cells in series, then through two 125 amp fuses in parallel, then the BMS and shut off switch, and 8 feet + 8 feet of 2/0 cable. I already calculated the BMS as being about 1 milliohm, and the wire is a fair share of this loss also. I even saw about 6 mv drop on the jumper cable between the 10S and 4S packs. So I am pretty happy with this value. I will try and measure just the voltage at the terminals of the 10S pack when I cycle the current on and off. On the charge side, with the battery bank at about 50% charge, I got a similar result. The current went from zero to 25.96, and the voltage went from 50.61 to 50.81 which calculates out to 7.7 milliohms all the way to the inverter again. I have done 50% capacity cycles for 5 days now, and everything looks great. I have not pulled the pack below 50 volts yet so still above 3.57 volts per cell. but at these cycles and the low current level, everything is staying cool. My wiring into the panel is still temp. The most current I could pull would only be in the 70 amp range, still just 0.2 C.

It is times like this I realize how much power that little pack can really put out.
 
Well after about 2 weeks I now have all 3 batteries online so 16 KWH of storage ( of which I use maybe 14 KWH as I am only charging up to 4.0 V so that I can prolong the life of these packs. I have been dropping over 2700 Watts of power via solar to them, and they have been responding very well. Solar system dumps from 6 - 10 KWH a day into them. This has been tons of fun to see power real power there when I need it.
 
My bank is still working great. They have been charging to 4.1 volts per cell, and then discharging to 3.6 volts per cell for several month now with no issues at all. My BMS reports 97% full down to 50% with those voltages. I did lower my full charge voltage to 57 volts (4.07 per cell) which works out to about 85% charge with the Chevy recall announcement. They are telling owners of the Chevy Bolt which these cells come from to not charge over the 90% capacity setting. At 4.0 you are well under that. I am pushing about 8 KWH in and back out each day. I have 2 strings of 14S3P.
 
Are our LGChem modules part of the Chevy Bolt battery recall? I wonder which manufacturing plant our modules came from- I think only certain manufacturing plants are part of the recall??
 
From all I can find, it was modules built in South Korea and sold in North American Chevy Bolts. There is no recall in other countries at this time. My modules are marked LG Chem Vista 2.0 made in South Korea. Only charging to 57 volts on 14S is working fine for me. They run stone cold. Have not seen or felt them ever any different temp than the metal cabinet in my garage. While on grid without my A/C running in the cool weather, I am able to fully power my home through the 5 hours of peak energy rate and still have nearly 50% battery left.
 
At last! I finally got the right connector after 4 times of odering ( my error for not understanding the different types of JST connectors ) but my bluetooth BMS is only. I am glad I got this now I can check battery voltages without fighting with voltage meter.
 

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Andrew, The side panels pop out you have to release each tab slowly before they come off.
I bought one of these modules as well, how easy was it to clip off the side panels to show the connections? I tried unclipping mine and it’s giving a lot of resistance, I don’t want to snap them off completely.
Thanks Mart for this tip. I realize I am way late here, but I had trouble with this initially, too, and so am posting some pics to supplement Mart's answer in case that's helpful to anyone else.
 

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I purchased 2 of the 10S 3P and 1 of the 8S 3P LG Chem Chevy Bolt packs from Battery Hookup as the cost per KWH was hard to beat.

All of the cell groups were well within .01 volt when I got them and they do look basically new.

So far I made up a mounting system to hold the packs in a 19 inch equipment rack.
I cut the middle buss bar of the 8S pack to split it into two 4S sections without physically separating the pack.
I made clamp on copper terminals with matching 6mm bolts.
I used #2 cables to wire each 10S pack in series with a 4S section to make two 14S strings.
I have each 14S string connected to a buss bar with 125 amp fuses.
I purchased a JKBMS with 2 amp active balancing and common port 200 amps protection switch.
I soldered wires to each cell junction and joined the 2 strings with fuses to the single BMS.

The JKBMS seems to be working great. It allows you to customize all of the parameters. I currently have the cell over voltage set to turn off at 4.2 volts and turn back on at 4.1 volts. The cell under volt turn off is set to 3.2 and the turn on at 3.3 volts. Full turn off if any cell goes below 3.0 volts.

I have the max charge current at 145 amps. With 6 cells in parallel, that is under 25 amps per cell, or less than 0.5 C rate. The max discharge is topped out at 200 amps, which is still well below the cell capability. It also has an internal temp sensor for the the protection FET's and balance circuits and then 2 remote sensors to mount on the batteries. The battery protection temps are also fully configurable. The battery bank will live in my garage in So Cal so low temperature won't be an issue, but it can exceed 110F here. I plan to extent the temp sensors and mount them where the battery get's the hottest.

I do not have my inverter/charger yet. My current plan is to use a Schneider XW-Pro. I would set it to limit the charge voltage to just 4.1 volts per cell, and the low battery shut down will also be set to about 3.5 volts so the BMS is only a secondary safety. This should stay well away from the BMS having to step in and shut it down. I do not have any load or charger here currently that can stress these batteries. I have pumped about 600 watts in and pulled nearly 1000 watts out and the cells seem rock solid with virtually no voltage dip and they stayed at just room temp. Once my system is up and running, it will mostly be used to do self consumption. Time shifting about 10 kwh from solar production to the 5 pm to 9 pm peak TOU charge time. But I will have my Enphase solar gear and my essential loads connected after the inverter so I will also be able to run most of my home during a power failure. Doing the rough math, I should be able to keep most of my home running off grid with all the sun we get here. Just can't run that A/C compressor.
Hi GXMnow,
Your set up sounds great. One question for you: you say you're planning to install the Schneider XW-Pro. I am designing my system now and am looking at the Outback Radian compared to the Schneider. I have a really similar battery set-up and am wondering if you compared the Radian and Schneider and prefer the Schneider. I'm leaning toward the Radian but am interested to know if I missed anything in my research and maybe am better to go with Schneider . . . Thanks!
 
Late to the thread, can you share you experience with this inverter pls?
Branks, $$, performance.
Thanksl
Sure thing, I am very pleased with this inverter. It has been running for months supplying power to my PC, frig, instant pot, bread machine, and several lights. About a month ago I pushed it too hard when combining both my microwave (1200 watts) combined with well pump ( pulls 800 watts ) and blew the auto fuse on one of the circuits. I replaced it and I was right back in business ( they send extras) Since that point I moved the heavier loads to my 24 V system and that has taken care of my problems, I use heave loads like table saw, and microwave on the 24V system, and my constant loads like frig I use this 36 V inverter. I recommend when ever using a Chinese inverter only using 2/3 of it's rated watts, and not for heavy lifting. It did run the microwave by itself, but I don't want to put any stress on the inverter more, I have gone as far as I am willing to experiment with.
 

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Hi there, I'm writing to see if anyone has figured out the pin-out on the 5.94 kwH module or the 4.75 kwH Module. I'll post some pics here of the connector (8-pin female) and of the modules I've got just to be sure that I'm being clear about the connector I mean - I read through another thread on another forum, https://secondlifestorage.com/index.php?threads/w0ss-semi-diy-powerwall-v2.8454/, but believe that the pin-out that Woss posted there is for a different module (pls. correct me if I'm wrong, though). Thanks for any help!
 

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Oh PS. I did go with 2 gauge wire to the inverter and all the connectors. I am glad I did
 
Hi there, I'm writing to see if anyone has figured out the pin-out on the 5.94 kwH module or the 4.75 kwH Module. I'll post some pics here of the connector (8-pin female) and of the modules I've got just to be sure that I'm being clear about the connector I mean - I read through another thread on another forum 'secondlifestorage,' but believe that the pin-out that Woss posted there is for a different module (pls. correct me if I'm wrong, though). Thanks for any help!
I have not but a word of warning....

Positive and Negative are not always on the same side of the battery. 2 dead BMS's later I figured it out, just verify positive and negative.

What I did was drill each tab on side of the battery and used small bolts to secure the connections, I tried soldering, but that was a fruitless venture for me, the bolts worked awesome.
 
I wish I could buy more of these batteries for $100 a KWH, this was such a great deal.
 
I have not but a word of warning....

Positive and Negative are not always on the same side of the battery. 2 dead BMS's later I figured it out, just verify positive and negative.

What I did was drill each tab on side of the battery and used small bolts to secure the connections, I tried soldering, but that was a fruitless venture for me, the bolts worked awesome.
OK, good tips. You probably saved me some serious frustration, waiting time on new replacement parts, cash . . . Thank you!
 
Taking off the buss bar covers is not very difficult. There are a lot of clips, but each one is easy to release. If you have a high power soldering iron, I was able to solder my balance wires to the tab where each buss bar is soldered to the PC board that goes to the balance connectors. I wanted to use the balance connectors for a few reasons, the main one being, there are already fuses on the PC board for each balance lead, but I was not able to source the connectors. Since I am connected right to the buss bars, I did use inline ATC fuse holders with 7.5 amp fuses incase a balance lead shorts, it will just pop a fuse. I drilled a hole and cut a slot for each balance wire in the buss bar covers so I could put them all back on with the wires poking out.

Both of my 10S packs have the negative on the right with the studs facing up, but my 8S has the negative to the left. But when you look how the packs are installed in a Chevy Bolt, the 10S packs could be either way, depending on which brick you get. Certainly check with a meter before you assume.

To make 14S sections, I split my 8S pack by cutting the middle buss bar with a Dremel tool. I cleared a gap over 3/16ths inch wide and covered the area with liquid electrical tape. It is basically paint on black rubber cement. The cut buss bar gap ends up with 4 cells of voltage across the gap, 16.8 volts maximum, so I am not worried about it arcing, but since it is close, a metal part hitting there could be a problem, so I did my best to insulate the area. I made clamps that use a pair of screws to smash a copper plate against the copper buss bar face. The plate sticks out of a slot in the buss bar cover and has a 1/4 inch (6mm) hole to bolt on the high current cable, and a smaller hole for the balance lead to screw on. At 80 amps, my voltage drop from the cable to the actual cell tab is about a little less than the factory end buss bar cell tab to cable stud drop, and they run cold with no heating issues. My two 10S packs are not modified at all except for the added balance wires. I only parallel the final negative and positive posts after going through a 125 amp fuse from each string. My balancer leads branch to both strings through separate fuses to each bank, so each cell junction is paralleled, but through a bit of resistance due to the #16 awg wire and fuses between them. This effectively gives the BMS the average between the two strings.

I agree, I would like to get another set and double up my battery bank. I will keep an eye for these to come up for sale again. The performance of these batteries is amazing.

As for my Schneider XW-Pro....
When I made the choice, the OutBack SkyBox was just coming out, not much info, and AC coupling was a "future update". Knowing what I know now, I probably would do a SkyBox. The Radian was interesting, but I was stuck between the 4,000 watt and the 8,000 watt. I just didn't feel the 4,000 was going to be quite enough. The 8,000 is not double, but it is quite a bit more money. You need several extra boxes to tie the system together, and the spring loaded wire terminals for a 30 amp 120/240 connection made me a bit nervous. For the money, the XW-Pro is a rock solid inverter. I do like that it has a real (VERY Heavy) transformer to drive the output. It can handle very unbalanced loads without any problem, and even helps balance the load and create a neutral while off grid running my Enphase microinverters which are only connected 240 volt line to line. It will easily take over 3,000 watts on one leg with no load on the other leg and run just fine. I do not think the transformerless Skybox would be able to run like that very long. I know the Sol-Ark has imbalance limits. The Schneider XW-Pro hardware has been running perfectly for about 9 months now. It never breaks a sweat. Even running 4,000 watts, the unit is the same temp as a metal cabinet in my garage, I do not feel any heat on it. The efficiency is also excellent. I am estimating the round trip efficiency at nearly 90% from AC in to charging the battery, to AC back out feeding my house. My 3Hp advertised (actually about 2 HP) air compressor is currently wired for 120 volt and it was on one of the XW-Pro output legs. Looking at my battery summary, I can see each time it started. The battery current would spike up to 70 amps, and hold at 60 amps. That is running all of my house loads and the air compressor, and it was still exporting 500 watts out to the grid all from battery. The XW was in "Grid Support" mode at the time, so it ramps it's current to keep my grid draw constant. In this case, the constant is "Selling" 3 amps (720 watts at 240 volts) back to my main breaker panel. That covers all the loads that are still back in my main panel and has 200-600 watts left over (depending on what is running) that goes out to the grid. These batteries and the XW-Pro inverter can run my entire house without breaking a sweat.

Now their software has a few odd "features"
I am still on version 1.03 set for California Rule21. It is stable and has only had a few times where it disconnected from the grid for a voltage or frequency out of spec, even though nothing else in my home saw anything wrong. Since it just flips to inverting to run the loads, I don't even know it happened except I see it in the log go to powering my backup load panel and the grid is disconnected. They are now up to version 1.11 and it sounds like they may have improved the grid stability modes to reduce these disconnect issues. But I need to shut my system down to install the update. I am not 100% sure I can have it hold in the contactor during the update, and my PC that is setup to run it is being powered by it. Oops. I will probably use my laptop for the update and bypass the router so if it does cut output, it won't lose network connection.

For backup power, or a system with DC coupled solar, I still think it would be hard to beat. The system can crank out the power under any condition I can throw at it. But my system is AC coupled with all of my solar coming in from microinverters. While the system is running on grid, it CAN'T time shift power all by itself. This is a very stupid lack of programming in my opinion. The grid support and load shave inverter function while on grid will all stop working when the battery bank falls to 0.5 volt above the "Recharge Volts" setting. So at the end of a day, when I trigger it to power my house, it will either shut down on time, or when the battery hits the voltage cut off, 0.5 volts too high. So the next morning, I have sun blasting on the solar panels, but the XW-Pro will just sit there in standby. It will not start a charge cycle, because the battery bank is still above the recharge volts threshold. At first, I kept going in each day to change the recharge volts and grid support volts to make it charge. And then I would change the values back at night to run the battery down where I wanted it again. I have since figured out, I can leave all of the values, and just go into the "Controls" tab and click on "Force Charger Mode = Bulk". That does start a charge cycle, and it will top up, and run pack down without intervention, but then the next morning, it is stuck again, and I have to do it again. Every Day. I have tried to explain the issue to Schneider, but they just say, buy our DC charge controller and rewire your solar panels. That is not a proper fix. It already has a time schedule where you can block it from going into charge mode. I just want them to add an option so when the charge blocked time ends, it will start a charge cycle. Why is this a problem?

The OutBack SkyBox has proper Time of Use and Self Consumption control all built in. It even has an MPPT charge controller built in, as well as the communication hub and monitoring. It is a true one box system. The Schneider may be a more solid inverter, but the software is preventing it from doing simple time of use power shifting.

The short time I have run off grid, the problem vanishes. It works great when the grid is down. It seamlessly fades from charging to inverting as needed to keep the demanded power feeding all the loads in the backup loads panel. When my solar makes more than needed, it pushes the rest into my battery bank, when I need more power, it will pull from the battery bank and help feed the loads. The only addition I would like to see is having a separate set of inverter and charger settings for when the grid is up or not. With the grid up, I leave over 50% in the battery, and I charge it slow and stop at 85-90%. When off grid, I want it to charge faster, push the battery to full, and let the battery run lower if I need the power. Having it cut off would be very annoying as the solar won't come on unless the inverter is making power. A DC coupled system does not suffer this problem. Any time sun hits a solar panel, the charge controller could be putting that power into the batteries. With my AC coupled only system, the battery inverter has to be running at least 5 minutes before the microinverters will come back online. Only then can the XW use the power to start charging again.

Schneider, Great hardware, but the software still needs some help.
 
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