Best way to wire batteries. Part 3
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- Опубликовано: 11 авг 2022
- Busbars will make a battery rack run more efficiently.
In part 2 we wired the rack of Jakiper batteries as a "daisy chain". We saw the wires were getting too hot in that setup. Now we re-wire the rack to a central busbar and re-run the load test. WOW! The results are amazing.
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Jakiper (Orient Power) sent me some of the new "PRO" batteries for testing and review. This is Part 3 in the video series.
This battery is part of the Jakiper line. Model# JK48V100PRO Server Rack design. The cell chemistry is LiFePO4 (Lithium Iron Phosphate) which is the leading chemistry for home storage. Each battery works with 48V equipment but is technically 51.2V nominal, 100Ah. This means you have 5.12kWh of capacity.
There are 4 batteries in the rack. This makes a total of 20.48 kWh.
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300 Amp Class-T Fuse and Fuse Holder: ebay.us/WGCX1c
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Orient Power Main Page: www.opsolarbattery.com/shop?r...
Jakiper PRO Battery: www.opsolarbattery.com/produc...
Rack with 4 batteries: Get a deal when buying the set of 4 with a steel rack: www.opsolarbattery.com/produc...
Powerwall battery is the newest version and hangs on the wall if you don't have a lot of floor space. The specs are the same as the server rack design, but in a vertical package: www.opsolarbattery.com/produc...
4 AWG (4 gauge) wires for connecting your batteries together: www.opsolarbattery.com/produc...
Rack alone: www.opsolarbattery.com/produc...
CC/CV charger for battery. (constant current, constant voltage)
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Videos:
Part 1: testing a single Jakiper battery. • Testing and Review of ...
Part 2: testing the full rack of Jakiper batteries: • Battery Banks - To Dai...
Busbar comparison: • Busbar Comparison Guide
Building the Watt meter: • Save Time and Hassle, ...
Disclaimer:
My videos are in no way intended to be instructional "how-to" lessons. I am simply documenting my project for informational purposes. Property damage, personal injury, or death may result, even when following manufacturer's instructions. I cannot be held liable for such damage or injury. It is YOUR OBLIGATION to ensure that you are complying with any local and federal laws as well as code and permit requirements.
David Poz, LLC 
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Ok, I'll bet your wife is rolling her eyes at a few of your (expensive) projects, but your kids adore you! That's your #1 job as dad, well done Dave!
I am a long time subscriber. Love seeing your friends and family members participate in your project throughout the years.
Thanks. My kids love helping me.
@@DavidPozEnergy I can’t believe how big your kids are getting. Enjoy them while you have them at home. Time flies.
So I guessed right using a busbar arrangement. Your work is quite valuable to us DIYers. (I now have one of those big ass fuses.)
Perfect workflow and presentation. The apprentices are learning quickly! It shows clearly they have a wise and patient instructor :-) Another way to quantify efficiency gains is to measure the change in voltage drop across the load-carrying conductors as they heat up, though how you've done it with a temperature reading does quickly get the point across in the video. Thanks (as always) for sharing with us all.
Great video Dave. Perhaps up sizing the conductors to the next size would also reduce power losses to heat.
You are definitely an engineer (and not merely a DIYer). I am overwhelmed just looking at your configuration, and intimidated at the prospect of trying to build a system (that hopefully won't be as complex, but also will be therefore less functional/ efficient).
It’s great seeing you teach her mechanical and other skills. The irrational fear many have of electricity creates opportunities for me as electrician but ignorance is not an asset for anyone.
Except for the one sitting in the oval office... ignorance is his bread and butter. 🤣
Hi David, thanks for making this video. Daisy chaining is one of the reasons I dislike server rack batteries. Thanks for showing people why this is a poor practice. Of course the other reason is that the batteries get used asymmetrically when there is greater resistance in the circuit from one battery to the other. That means that your C. rate will be higher than it needs to be on one or two of the batteries early on and it will shift to the others later in the discharge. Thanks again sir. I have learned a lot from your channel when I was getting started in this DIY journey. I like your style as well.
Thanks for the video David. Great presentation and explanation of the benefits of busbar configured battery storage. I realize most will know the tidbit of heat adds resistance, which creates more heat (nice to see the lower temps here). Also great to see the kids involved as well!! Keep up the great work ☺️👍!
Thank you for your nice comment.
Heat is the result of resistance.
@@DavidPozEnergy In your code book there should be a generic torque table for different stud sizes types, If any part may lack that info
Very good video. This is a quantum difference. You did an excellent job of defining the reason and results of the busbar system vs daisy chain.
This is foundational battery info.
Thanks David.
Thanks for your comment. I hope the information helps the DIY community.
Great video David -- Was hilarious seeing your kids running around with the terminal caps on their fingers!
As always brother, you are fantastic. Great dad too!
Nice to see Elenor as she grows. 🙂 I agree with the busbar approach.
Excellent presentation highlighting the benefits of using bus bars instead of daisy chaining. This is why I think Signature Solar's rack mount enclosure with the bus bars is superior to the other rack mount options that I've seen on the market.
So cool that you get your kids involved in your projects.
I would recommend a thermal imager for looking at the temperatures of various components and wiring. The FLIR One connects to most smartphones.
Good to see you training up the next generation of engineers 👍
very helpful
nice, also great points about the solid bus bar and expansion issues..
Thank you.
Thank you, David for this most valuable information. Stay Safe!
Busbars are the way to go for sure. I have the EG4-LL batteries and the 6 battery enclosed cabinet with built in busbars. Those are most similar to your setup here because each battery has a jumper to the busbar so nothing in front of the battery is blocked or putting stress on the terminals. Cheers
@11:00 - If more parents would get their kids involved with their own projects/work we'd have a much better society to live in. Great job! I remember working with my Dad in his shop as a 5 y/o. Those are the years when you instill in your kid the work ethics they will need for the rest of their lives. Thumbs up sir!
Great job on demonstrating a DIY the right way. I'm not crazy about the plastic the bus bar is mounted to, I would prefer something like fiberglass, but if used within its rating, it's fine.
Dude that beard.. I can’t get used to it
LOL. It's fun.
Hadn't seen a video in a while and oh yeah it's a shocking change lol.
Teenwolf!
Same here!!
I was wondering if your wife traded you in or something 😂
Thanks for the video David. Great presentation
I was surprised by the difference. Thanks!
Hopefully surprised in a good way?
Great Job David...the system is much better now!!
Regards..
EG4 are set up like that on their racks. My system runs cool to the tough all the time. Excellent video!
Always good info. Thank you. Kids are a joy. God bless you. Thanks for sharing
Great job ... awesome video. The difference is amazing.
Great work David. Cute helper too. My she has grown so fast.
Thanks for posting this test, as I am about to connect 7 batteries together. I will try my best to use same wire length. I dont have a server rack like you, but bought a home depot husky rack to hold the batteries. Its rated at 5000lbs. (We will see).
I'm sure that shelving unit will work great for you. Are you going to have any videos on it?
you're a SAN dude ;)
i'm sure you can find a second hand san rack on ebay somewhere on ebay
If you increase the wire gauge a few gauges (which is always a good idea anyway) you don't have to be so concerned about making sure the lengths are the same. They just need to be close but the larger the gauge, the less voltage drop, since internal resistance is lower so it will make less of a difference under heavy load with larger wires. Your crimps and connections will be more important than a small variation in wire length if you use a larger gauge.
David, you were the very first YT person I followed for batteries and solar. I love how thoroughly you go through everything and I always learn from your content. I will be building out my system next spring using 6 of the EG4-LL batteries and the Sol-Ark 15k. Yes, I know your thoughts on the Sol-Ark but I need something fully UL certified for codes and will be using it for a whole home backup and to save on time of use charges until I get my solar arrays in place. I have also spent the last year analyzing my loads using the Emporia Smart Home Monitoring solution so I hope to avoid the unbalanced load issues you were seeing. Waiting on Solar until I can win the HOA battle, Oklahoma doesn’t have a law luke CAN and other states do that prevents HOAs from banning Solar. Keep up the great work and thank you for inspiring me!!
Hi EB, thanks for the comment. I wish you luck against the HOA. I wish HOA's were more willing to accept solar. When you choose to buy some EG4's, please use my affiliate link as it makes a huge difference for me. These videos take an enormous amount of time.
@@DavidPozEnergy You can count on me using your affiliate link. I plan on going down to visit Signature Solar on 9/9 & 9/10 and will make sure to share your impact on the community while I am there. Not going to buy yet, just visiting while I am “in the neighborhood”. Send me a DM if there is anything I can get for you while I am there. I cover shipping up to $300 for you. I’ll also you your link for Sol-Ark and panels so I’ll reach out in March when I will be ready to buy.
That's generous of you, thanks.
Very nice video David.that way we can balance discharge and charge currently of battery pack.
Thanks David and helpers 😀
Great demonstration of the effects of cable resistance. You are effectively reducing the current through the cables by a factor of 4, thus greatly reducing the effects of cable resistance. Since you have two terminals on each battery module, you could double up the cable connections to the bus bar to decrease the resistance by an additional factor of 2. I don't know if this is cost effective, or the gains would be worth it, but you could probably reduce cable temperature rise to single digits. Probably approaching the point of diminishing returns...
Using ohm's law the power loss on each cable, link between the terminals on a battery pack, etc, in the daisy chain can be calculated. V x I. Amps is what the clamp meter reads, V is the voltage drop across the thing being observed, ie a cable, a link, etc. At full tilt, 400A, through the top cable 30mV of drop would equate to 12 watts. That's more than enough to heat up the cable, but in the overall picture considering the load (400A!) that's not a lot of power. I'm guessing at full tilt daisy chain loss would total maybe 100 watts. Sure it's more than nothing, but again considering the power draw to get there, 20kW, it really is nothing to worry about so long as the temperature rise stays within the rating of the insulation in its installation environment. That said, there's nothing wrong with a cool running system and it would be 100 watts less to remove from the room the equipment is in. 30mV drop was fictive, actual drop may be higher so measurements would obviously need to be done.
Thanks David, I love your work, congratulacion from México City
One of your best videos to date. thanks
Great to hear, thank you.
Great video David!!!
Great Stuff.. Watching from Kenya!. Love the kids too in the mix😊
Love the new beard! Hopefully you like it enough to keep it, even in the summer! Woof! As always, love your content!
First, I think the long hair and beard on you looks terrific! Once I got over the shock and realized that it was really you. Great job and video series, David. I'm curious about how you incorporated your entire wiring system in your home to the breaker panel in your garage that your solar system's AC power from your inverters is connected to. Additionally, how much voltage and amperage is the breaker switch between the inverters and AC panel rated for? Lastly, do you know any way a poor old man can get a rack and 4 48V server rack batteries given to him without making hundreds of RUclips videos? Great job, as always, my man!
Our old standard for copper buss was 1 sq in per thousand amps - 6" x 1/4" gave us 1600 amp buss. But then we were running continuous heavy loads in hot environments. Also guard those fuses against becoming shrapnel. Heaviest I ran was an 8 stack of 1x8" for salt tanks.
Thank you, that rule of thumb is very helpful.
@@DavidPozEnergy I think what Bill Burton is trying to say is that your bent bar, based on his rule of thumb, being 1/8" x 1" or .125in square is capable of 125A. I didn't know that rule of thumb so I just look it up in tables, and I've found that a 1/8" x 1" bar can handle 270A with a 30 degree C temp rise. It won't ever get that hot because the fuse block and junction block will act as heat sinks. For comparison your bar is 0.125 , 2/O cable is 0.1045 and 3/O is 0.1318 square inches cross sectional area. What you have is fine, but if you had to make it again I'd use a thicker or wider copper bar.
This may have already been said, but during this entire video I was thinking, "why not run a solid copper buss bar from the inner posts"?!?! But after watching 22:53 in to the video, I found that you covered that! Good job! Thank you, and great video!
Thanks for watching to the end.
I run a combination of daisy chained with a 1000A buss bar. The reasoning for this is that I have 20 batteries, so both daisy chaining and buss bars alone would not be appropriate. I have 4 banks of 5 batteries. Each bank is daisy chained, then combined on a 1000A blue sea systems buss bar, where the inverters also can be tied in. With the size of the battery pack, even at full output with 3 inverters I’ll never pull more than 30% of the max battery output anyways, so the daisy chaining isn’t a big deal as far as balancing the load in each battery goes.
Priceless information. Thanks for sharing.
Good to know, thanks very much for sharing.
Great Job! I hope they appreciate it.
Good video as usual. Busbars are absolutely better than daisy chaining.. I use aluminum power distribution blocks for my busbars.
I just bought two of these batteries and will be getting two more in a few months. I will make my own cables or of oversized welding cable. Possibly 25-35mm2.
I'll also make my own bus bars out of thick copper flat bar with stand offs or the plastic sheet stock. Lots of options. I think diy is better, more flexible and more cost effective than pre made commercial product.
Never skimp on good fuses either
Awesome video, very very useful test !! Thanks for sharing !!
Your welcome, and thank you for watching.
Awesome video David . Thks
Great video. Thanks for the great videos.
Hello David, great videos, I've learned a lot. For this setup I have an idea to test. You could connect the trunk on one of the middle racks, maybe on the second. Then 50A would flow over the top line and 50A+50A=100A over the bottom line. OK, that's more than with the busbars, but only half of the first variant. How is the warming then? Best regards and keep it up. Jan
For overkill I suppose you could use the second terminal to provide an alternative route for battery to battery balancing current and just use the side buss bar for input and output.
Unreasonable overkill but could be fun.
I usually fuse the negative side and use switches or breakers for the positive side. Blue Sea Systems make a great 1000amp busbar, and great class-T fuse holders.
Al Borland lol. you gotta rock the plaid shirt !
Any heat increases resistance. Increase gauge til cool. Love your video’s.
Great video
Another nice video. Since you were taking temps on the 4ga to the bus bar, I would have also liked to have seen the output temp on your exiting 4/0. Wouldn't expect a change from the initial setup to your modification, just curious.
Yeah, it never occurred to me to measure the 4/0 since it was a constant. Next time I run a load test I'll check what it is.
You could also secure 3ft bus bars to the rack with stand-offs and run cables from the batteries. That'd let you use shorter cables and keep them out of the way.
Absolutely. That's how my Gyll batteries are built: ruclips.net/video/r0vuSo5eIOY/видео.html
Sick video bro
I use 1/2"copper tubing works very well.
Nice work on the busbars. One thing I don’t understand is why the fuse is rated at 300a when the max your inverters can draw is 200a DC. I’d down the size of the fuse to protet the inverters from a potential surge.
I used a 300A fuse to protect the 4/0 wire.
Thanks David for the awesome videos especially this specific one with busbars. You and you cute princess really made my life simple as I was always wondering why is my middle battery always fully charged before the others and it has higher cycles than the other two. I will definitely get the busbars for my three batteries with expansion to the forth one. Will this setup make any difference whether you are using Li or USE on Setting 05? Thank you once more and keep up with those great informative videos.
Changing the layout of wires will not require changes to your inverter settings. Use the inverter setting best for your situation.
Good job. That looks soo much better!! Though you did forget to stagger the main positive and negative. You have the main positive and main negative on the tops of both bussbars. Sure it shouldnt make much difference since the bussbar has a nice low resistance, but it still has resistance. So just move the main negative cable to the bottom and shift the cables up one.
Though as long as it doesnt trigger your OCD I dont mind either 😉
Cheers keep up the awesome battery/inverter creations!
hmm also stacking the terminals isnt great either. you need 5 terminal bussbars
I appreciate the time you took to write a comment. I disagree with you about the need to stagger the +/-. I actually address this exact question, and then demonstrate it in the video.
@@DavidPozEnergy yea, I saw, The bussbar has such low resistance it doesnt make a noticeable difference. Though I think the main imbalance is from doubling up on the studs, then the ESR of the packs.
You could improve efficiency by making all your wires the same distance from the bus bar. Also 4 gauge wire will heat up if you draw large amps out of each battery. 00, 000, or 0000 would give you more max output from each battery. But keeping the wire distance the same from the bus bar to the battery terminals will give less resistance and less overall energy loss.
All the 4 gauge wires are exactly the same length.
The max output for each battery is 100amps and 4 gauge welding wire will handle that easily, though during his load test at 95% he didn't go much above 55 amps on any of those batteries. So he's still got a lot of headroom left, plus his fuse will limit it to 75 amps per battery since it'll blow at 300 amps which would be almost 17 kilowatts of draw. If he had fewer batteries then it might make more sense to upgrade to heavier cables.
You could put a longer bolt and put 2 lugs on the first battery(in and to 2nd battery) with a 1/0 wire, then next battery with a 1 awg wire, and last with 4awg wire. Could also use a double wire lug. But the advantage of having a central buss bar the way you did is that you can remove a battery from service without effecting the others.
Huge difference.
Another alternative test that would be very interesting. Using fully charged batteries show the difference in time with a specific load(1000watts). Run both ways to reach 50% point. So I would see how much difference exactly this improvement makes.
Another point about busbars that directly connect all the batteries together. With busbars you can't easily or very safely disconnect a single battery if you need to. It can also be more difficult to insulate the busbar between terminals though it can be done with judicious shrink tube efforts however the little plastic cable caps don't work then for the terminals.
Holy Lumberjack! Dude you look 😍 amazing!
Again, a nice video David! One other thing about NOT using a busbar over the terminals is that you are not able to remove one battery.
I think you would better remove the 'stuff' in front of the vertical 19inch strips at both sides and move it 2 inches. Then you are able to remove the battery's without worrying.
Working clean is my preference, sorry😉.
Ps. Are the 2 connection blocks on the wall, left of the 3 switches, AC, so >100V?
The terminal blocks are 120VAC. Yes, I have to get them mounted inside a box. I have a din-rail box waiting on me, just haven't made the time.
nice one
Excellent improvement in design! I hadn't considered the heat/cool expand/shrink component of connecting the batteries with a big long bus bar. Excellent overview!
22:11 I noticed a big thick tan cable running to your positive bus bar at the end. What was that for?
That is my temporary parallel wire to my Gyll battery rack. In a future video I plan to have another busbar on the wall just below the inverters and then I'll move the wires over to that. But the tan wire is 1/0 and has it's own fuse over at the gyll batteries, so it's OK for now, but not clean.
@@DavidPozEnergy Cool, got it. So you ran your Gyll pack in parallel with the Jakiper setup? Any issues? I assume not, it's just batteries! Thanks David!
No problems. But, when you do it the way I did, there is more resistance in the tan wire to get to the Gyll stack. This means the Gyll stack lags behind the Jakiper battery by about a tenth of a Volt. Once I get my new busbars up on the wall and run both stacks in evenly, then they will move up and down perfect.
My favourite caveDave! ;-)
Thanks that was very interesting. Best of luck to you all. M
Perfect way to hookup batteries. This way will extend the life of the batteries. Heat is the enemy.
Thanks for watching.
Definitely makes sense. Instead of the load passing via basically a 4 gauge cable with each battery adding more load to it at each daisy chain point, you now have each battery using it's on dedicated 4 gauge cable to the busbars with the busbar passing the load to the heavy cables tied to your inverters. Not that it should make much of a difference with the short jumpers you have but ideally the cables to the busbars should all be the same length as well, this minimizes the voltage difference and will spread the load as evenly as possible.
I agree. All the 4 gauge wires I have are the same length.
Btw, the US really needs to start using NH fuses, they are so cheap here in germany, a 300A NH2 fuse (rated up to 440Vdc, smaller fuses are rated for 250Vdc) with 25kA DC interrupting capacity, with base will cost me roughle 15€ used or 35€ new.
Good Tests showing the bus bar type installation.
BTW David... how is the last 38 SEER DIY Spilt A/C you installed yourself running?? Thinking of investing the $$ to install the same unit myself.
The mini-split in the garage has been running 24/7 since I installed it. Working great. I should probably check the filter at some point, LOL. I haven't touched it.
Nice video David thanks for all your effort producing this information I will certainly be using a busbar of some creation. I just wonder is it really necessary for the extra fuse on the busbar as all the batteries are individually protected with 125A MCB or are you being ultra cautious?
There are a couple things at play.
1. Over-current protection. The 125A circuit breaker on each battery provides over-current protection for the short (14") wire from the battery to the busbar. But then what? Where is the over-current protection from the busbar to the inverter? You might have a large circuit breaker at the inverter, in which case, you don't need to add the fuse. In my situation, I'm paralleling this rack to another rack, so I needed over-current protection somewhere.
2. Short-circuit protection. Circuit breakers are fairly slow to trip, and relatively low in SC amps. The fuse I used (Class-T) has a very high short-circuit rating, and is very fast.
TLDR: You may not require the extra fuse, but it depends on the situation.
@@DavidPozEnergy Okay fully understood thanks again
I love dryer tests.
Yeah, Dryers are surprisingly hard testers.
@@DavidPozEnergy 2 kW is alway right.
I'm not sure if anyone has commented but u have a thick 400AMP busbar connected to the fuse with 3MM copper plate on a rough observation it is about 20 x 3 MM which calculates to 84AMP rating
Damn I think it’s time I retired my vice. That thing is CLEAN! 😂
You did a great job measuring the temp of the wires. What was the temp Delta of the main feed to the inverter?
Sorry, I didn't bother measuring the 4/0 wire since it wasn't the focus of the video. I remember it was warm, but I could hold my hand on it without feeling "hot". Would you like me to make a "shorts" video just checking the temperature of the 4/0?
Another excellent video, thank you for the experiment! Question: can you tell me the manufacturer/model of those white solar shutoff switches you are using mounted on the wall behind the top battery? I’m looking for that exact configuration. Thanks David.
Those are PV disconnects, made by IMO. Here is the switch inside a water-proof box: signaturesolar.com/dc-disconnect-rooftop-isolator-switch-by-imo/?ref=4_rHcgZ9x-TiF- If you want it without the box: www.industrialcontroldirect.com/modular-dc-disconnects-si32-dbl-4-6028.html
Perfect! Thank you David! For whatever reason I couldn’t locate them. I googled for an hour or two trying to find them. Keep up the good work! You are sharing some very educational and.valuable info.
Great video. Nice touch having your kids helping out. Do you have a good source for copper bus?
I have links in the description for the busbars I used in the video. They are made of solid copper, 1/4"x1"
@@DavidPozEnergy I'm looking for the 4' copper flat bar stock that you showed later in the video. Any idea where I can get some?
Yes....efficiency! >=]
Very interesting, never considered expansion of copper bus bars but it makes sense, how often would you recommend to retorque battery terminal bolts?
When I worked in industry, I think think the electricians had a 1-year rotation on things like this. That's probably a good approach. If it were me, I'd check the torque after the first full cycle, then after 1 week, then after 1 month. If they stay torqued after the first month, then once a year after that.
Hi! Good job David, and firstly i have to say; this beard fit you very nice! 🧔 But why don`t you use a thicker cables between those batteries? They`ll probably not cost too much.. 🤔👍
I think anyway the connection order on both busbars has a matter, that's maybe why you did have a small unbalance in those batteries.
Did you try to connect shunt and fuse at the opposite sides of the busbars?
Thanks for the video!
Nice video David. Please I have a novice question for you. Why are there more amps running in the main positive cable compared to the main negative?
The two are always equal. I'm guessing you are asking because the Victron Shunt was showing about 210A (neutral) and my multi-meter was showing about 220A on the positive. Is this why you are asking? If it is, then the answer is the different tools, and margin of error. If The shunt was on the positive it would have also showed 210A.
heya that is much better great job
since both connections coming off the batteries are from a single busbar you could just use 2x 4awg cables will handle 200Amps easily.
If you arc the bus bars between the batteries you gain the flexibility so you can tighten the nuts without having to slot the holes, and you won't block the screens or ports. You would use more heatshrink.
That would be interesting. Have you seen anyone do that across 3 feet of copper bar?
@@DavidPozEnergy I've seen arcs used in other fields to allow a controlled flex between 2 ridged points. I've seen it done in plumbing when there are wide temperature swings in the fluid or gas. As you can imagine metal pipes also change length with temperature.
There are charts and formulas that will tell you how much copper bars will change length for a given temperature change. If you make a curve in the bar it will curve more when it gets hot and straighten out when it cools down.
Dave If you ever need more 48v 100a server batteries. I buy a lot of Jakiper for over sea in Ukraine.I can sell you customs server rack or wall mounts for $1,400 each or $1,350 for 5 with free server rack. plus shipping straight from wear house.
Love your RUclips channel.
Man you really threw daisy chaining under the bus!
Thanks David, nice video! But wouldn't it be better to have all the wires in equal length ? The shorter wire does charge and discharge faster than the longer wires. Or is it, practically seen, marginal? Just wondering.....
All the 4 gauge wires are exactly the same length. Maybe it looks odd because the one on the bottom makes a little loop?
Really nice video! Thanks for that :)
Btw, the "daisy chain" is how I have them wired, with BMS connectivity to the inverter. Do you know if the BMS connectivity between batteries + between 1 "master" battery & inverter are also valid with this "bus bar wired way" ? I'm not sure how the electricity goes out when the battery is connected to the inverter 🤔Can they be parallelized as you show too?
Thank you.
Yes. The communication won't care if your batteries are paralleled using the daisy chain method or the busbar method.
You can only daisy chain 2 batteries without unbalancing the loads on the batteries too. Main pos and main neg to different batteries. But no matter how you set up your daisy chain with more than 2 batteries the ones with the mains will see more amps pass through and fewer amps as you move away
I work on RVs. And see lots of what are basically small house inverter systems. A lot of the newer ones have lithium ion batteries similar to what you have. And they have charge controllers to balance voltage. They use an extra wire to the negative to vary the ground side potential I believe. But the older big class A’s with big inverter’s with lots of flooded batteries always had better performance from 6 volt batteries for same watt hours of batteries vs 12 volt partially because now I can run 4 batteries from 1 main neg and pos with a balanced load since will be wired as a pair in series and parallel but making 2 12 volt batteries instead of 4 in the same space. Putting more than 2 battery packs in a daisy chain will always make an unbalanced load and more stress on your end batteries.
The charge controller can balance batteries on the charge cycle but not the discharge cycle.
If you need more then 2 batteries you should not daisy chain or use appropriate voltage in series to make a 2 battery pack system. So off the shelf batteries much more practical to have your bus bars and only daisy chain 2 battery systems of relatively equal potential