Current Sharing Experiment: 25kWh LiFePO4 w/ Diagonal Wire Configuration
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- Опубліковано 7 лют 2022
- Server Rack Batteries: www.mobile-solarpower.com/ser...
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Every video includes some form of paid promotion or sponsorship. Some links on this youtube channel may be affiliate links. We may get paid if you buy something or take an action after clicking one of these. My videos are for educational purposes only. Information is subject to change/update at any time. Electricity is DANGEROUS and can kill. Be smart and use common sense :)
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Some are saying that this configuration should allow for equal charge and discharge. Not true. One of our forum members did the math! Check it out here. It shows why I got the results I got:
diysolarforum.com/threads/some-modeling-to-go-with-wills-current-sharing-videos.35121/#post-439794
Beginners should check out the free PDF from Victron called Wiring Unlimited. It is a fantastic resource if you do not understand what is going on in this video: diysolarforum.com/resources/wiring-unlimited.2/
Part 1 of this current sharing series: ua-cam.com/video/oXBT8lSC25M/v-deo.html
Server rack batteries: www.mobile-solarpower.com/server-rack-lifepo4.html
All in one systems: www.mobile-solarpower.com/all-in-one-122448v-packages.html
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Does off-grid solar confuse you? Check out my DIY friendly website for solar system packages and product recommendations, and so much more! www.mobile-solarpower.com
Join our DIY solar community! #1 largest solar forum on the internet for beginners and professionals alike: www.diysolarforum.com
Check out my best-selling, beginner-friendly 12V off-grid solar book (affiliate link):
amzn.to/2Aj4dX4
If DIY is not for you, but you love solar and need an offgrid system, check out Tesla Solar. Low prices and great warranty, and they can take your entire house offgrid with their new Powerwalls: ts.la/william57509
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Contact Information:
I am NOT available for personal solar system consult! If you wish to contact me, this is my direct email: williamprowsediysolar@gmail.com
Join the forum at diysolarforum.com/ if you wish to hang out with myself and others and talk about solar
FTC Disclosure Statement and Disclaimers:
Every video includes some form of paid promotion or sponsorship. Some links on this youtube channel may be affiliate links. We may get paid if you buy something or take an action after clicking one of these. My videos are for educational purposes only. Information is subject to change/update at any time. Electricity is DANGEROUS and can kill. Be smart and use common sense :)
DIY Solar Power with Will Prowse is a participant in the Amazon Services LLC Associates Program,
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Could you cut/drill some small copper bars, very short, that fit the width of terminals, then bolt your larger lugs onto on the other end? Sufficient thickness to handle the currents involved? Sort of like an extension.
I have the hard copy of Victron's "Wiring Unlimited", so I recognized your diagrams. But again, the conductors are different lengths in that example. I'm thinking the important lengths are the jumpers connecting battery to battery and not the lengths to the load. Would you agree?
Can you do a video on how to size bus bars?
@@jimsjacob yes, exactly.
@@MYCHANNELWITHMYSTUFF find a table of wire gauges and resistance for pure copper wire, pick the gauge you want, then calculate the cross section of that gauge (pi*R^2). a bus bar thats X wide and Y thick has X*Y cross section. example, 2/0 is 0.365" diameter, so thats R=0.1825, pi*R^2 is 0.10 square inches. so if your bus bar was made from 1/4 inch thick copper it would need to be 0.4 wide (0.10 square inches / 0.25 inch thick == 0.4 inches wide) to have the same cross section and DC resistance as 2/0 wire.
Hi Will I'm 56 single female and at 55 because of watching your videos I felt confident enough to design and build a off grid solar system. It worked perfectly from the very beginning and has worked since... its going on 2 years. Your videos are so informative and you are such a good teacher...Thank you for all of the thrilling opportunities. Tammy Halcomb
Would be interesting to a thermal camera to your tool kit. Would be cool to ‘see’ the cables warming up. It would also be handy to help identify bad crimps or bad connections too.
I absolutely love these battery tests! I spend do much time wondering about the best ways to wire batteries like I going to reinvent the wheel, then will not only does the tests but explains everything in great detail.. thank you @DIY Solar with Will Prowse
Man, this is top notch. Nothings like a visual demonstration like this
Fascinating results, thanks for the additional testing!
Will, I really liked this hands on example of a practical system. This is the best of the internet.
I have read (and heard of) all the different things that were demonstrated in this video, but this is the 1st time I've actually seen it. Outstanding video, Will!
Can't wait to see the busbar version of this experiment. nice video
Awesome video as always Will.
One of the things I really appreciate, is the fact that you stay on real world topic. And Don't drift off into minutiae that nobody really cares about. Not to mention the fact it over complicates. I consider myself a novice at best. Please keep them coming big guy!
In the Army we wired the batteries diagonally. This was something I learned in AIT Electrical Engineering, to balance the charge and the load and get longer battery life. Those were lead acid batteries on trucks though. Glad to know it works even on LiPO batteries for when I convert over from lead acid. Right now, living alone they work for me and are less expensive up front.
sadly, the dual batteries on virtually all diesel pickups like my ford f250 are NOT wired diagonally. each has its own chassis ground wire, and the loads are all connected to one, which has a fat wire over to the other.
Good to see it working well. I have 12x 100A lofepo4 connected the way you showed at the video!
You have alot of effort put into this channel , you are the boss on this topic !
It’s actually quite simple. When the batteries are at the top or bottom of the curve, the large batteries will supply more power (amps) as they’ll stay in the steep curve longer than smaller ones (they’ll be both supplying the power and pulling up/charging the smaller batteries). Once they are in the flat curve all will contribute the same as all will be around the same voltage. Once they reach the bottom curve, the large batteries will supply more power again as they will still be in the flat area - they will “prohibit” the small batteries from dropping - keeping the voltage at the flat area.
Bottom line, if you want to use this type of setup, especially with LiFePo4, just keep the voltages very close to the flat area. Then 99% of the time, all batteries will be contributing the same as they will have limited voltage differences.
Exactly!
@@WillProwse in future can you do some ebike battery testing and budget ebike testing please PLEASE
@@richardhobbs7107 I just received a Ancheer Hummer model ebike and I want to modify . I do love it so far but 22 mph in full electric mode is to slow and replacement battery packs just have me scratching my head I can't tell good ones from ripoff junk
It would be useful to know how much of these SOC differences are due to their curve characteristics and how much is actually due to voltage drop.
Awesome and useful test and proof points. It also shows how well the MPP LV6548's handle large loads!
i bought the book -mobile solar power - made easy thank you for writing this - very easy to understand
Hello Will. I just want to say thanks for all of your videos. You have the coolest job and I really appreciate the information and tutorials. Keep it going! You’ve inspired me to put together a 12V 600Ah system for my RV and I’m in the midst of building it now. This battery test video reassures me that I should be okay to use 4/0 cable and hookup my six 100Ah Lithium batteries in the same diagonal wiring configuration you have demonstrated here. I hope to be finished with it in a few weeks.
It always good seeing you do your thing, great job. Thanks 👍
Great test example Will. Well done 👏
Thank You Will, every one of your videos are a learning experience of eminence value. Amazing you give it away. You are a good man.
Love how detailed your vid's are great job as always. I can't stop looking at the screwdriver sitting on top of the batteries tho lol
Pulling current like that in an experiment is just fun. thankyou for the real world example
Thanks for the tests and knowledge.
Thanks for sharing your results. Much to be considered...
Very informative. Thanks Will, keep them coming!!!
This was a great understandable video Will! Thanks for sharing!!
I use a bussbar with opposite connections and have no issues and highly recommend it, well worth the investment
Awesome Content. These videos are very helpful learning material.
Thanks!
I am so grateful for your content Will. Thank you so much! A++ work sir.
Really nice example!
I love how excited this guy gets by some batteries.
Will it would be nice to do a video using copper buss bars and comparing the results to your other videos and seeing the different numbers.
Great job explaining.
Excellent demonstration. My system uses equal length conductor paths which I prefer although in a larger system that would entail buying a lot of copper. Your diagram called it Post pattern.
I was thinking this last night when watching your video on top balancing lifepo batteries.
Oh my word that load test was just insane!!!
Right!! So fun 😁
Bus-bars are the same as a diagonal configuration but essentially with a larger conductor. At some point a battery bank grows large enough that you would need really thick and long bus bars, so it becomes more economical just to have equal length conductors from each battery to much smaller bars (length wise).
Yes very true!
Watching this again because as I mentioned elsewhere I'm playing with a lithion and lifepo4 parallel packs connected to the same inverter. It really I testing how the two act differently but the major item I'm noticing is how they share current. It is really I trusting. I've got a pile of wire from changing lengths, guage, and I've ven recently changed the connection location. The lifepo4 likes to dump current but the lithion shines on low current constant load situations. Best way to thoroughly learn is with your hands. Personally anyway
Very nice presentation
Heh...in grad school I had a high-current, low voltage experimental rig that used 5000 watts at 12 volts. 0000 cables, brass connections, and they still got hot enough to melt lead solder. Had to use silver solder. Rig was, of course, water cooled, even near the connections...but that was a LOTTA current. Of course, we were heating carbon tubes up to 2500 C.
Another great vid!
Excellent Demo.
Always appreciate the knowledge that you share with us. PS I miss your informal live streams too I’m just saying.
I think that answered my question perfectly. Better, but not best.
Question: Do the positive and negative wire lengths from the battery to the system need to be the same length? I see in the diagram, and also in the video, that they appear to be different lengths. I'm asking since it seems to be important for the cables connecting the batteries together to be the same length. Why not so in connecting batteries to the system?
just great information on this channel
Great info as always, thx
Thank you for the video report .
Hi, love your vids
Hey man, this was a pretty cool experiment. I noticed you didn't measure the voltage drop across each length. That would've really helped explain the variation and show how much the diagonal configuration is normalizing C rate along the chemistry's discharge curve compared to the daisy-chained configuration. Then, when you mention how bigger batteries have lower internal resistance, it will actually provide context towards the experiment you're running. In addition to calling out current and SoC, please call out the pack voltage and if it isn't too much trouble, the voltage drop across the cable segments.
Thanks for the vid.
These last two videos have a dress questions that I have had for a long time. I’m still re-watching them to make sure I understand everything and I just ordered some appropriately sized fuses so that I have my batteries properly protected. I keep learning from you but like someone else said earlier I am especially admirable of your focus on safety. I have a neighbor who is trying to learn about solar and he is putting one into his RV. He’s been watching your videos but I don’t think he’s listening closely as he had four 100watt panels in 2s2p connected to a controller with a 50 foot piece of extension cord with the ends cut off, all feeding into a 3000 W inverter. Think it was 16 gauge. The inverter came with cables which were intended to be paired but he only had single cables on them. His components were correct per your plans but the wiring itself was downright scary. I think I’ve got them straightened out. A bit more focus on correct and appropriate wire size would be helpful for the newbies. Otherwise I’m always really loving your videos.
Will, how about doing a video on specific bus bars?
Interesting results. It looks like it depend on battery itself. I didn't expect it will be like that.. It might be good lesson for ppl who got a lot of parallels cells or systems..
I have to get my electrian to watch this vid before the install of my batteries on my boat. Thanks Will...!
Nice Test !
only thing left to do is show us the bus bar setup with these packs! :D great video Will
Keep it up!! I love it. Thanks Alot!!
Thank you for this video
You need 5 rack units of the exact same brand put in an actual rack. Then do the following tests. Wire it 3 ways: Bus bar, same side, opposite side. Cycle each method and record each battery for % of total amp draw at 100/75/50/25% state of charge. This is a lot of work but would fully prove how each one performs. I agree that it will most likely level out once you pass the first 10-15% of a battery charge.
Yes I plan to do that soon. I don't have that many packs but will soon.
Bus bar is only method I've found to work every time.
consider use one DC current clamp to capture the current as each battery and make consumption calculation be good.because each battery inside meter not the same reading sir.
Thanks
Very informative
Nice video … would have loved to see you measure the voltage drop across the conductors to make your point with numbers.
The difference in currents between the rack batteries in parallel are because of the difference in capacity. The larger the batteri the more amps needed to get same SOC . Discharge same pattern where the larger ones deliver more amps becuase of the larger capacity
cool video, thanks
Try using the diagonal configuration, take the power leads to the inverters out of the batteries 1 battery from each end. This will reduce the current from the jumpers that got hot and may allow the batteries to discharge more equally.
After what I can see and also what he is saying this IS diagonal configuration...
Well done, Will. A very clear picture of the issues of parallel battery design.
Someday, we'll get away from these ridiculous low voltage batteries for home power. I think 120V should be the practical minimum, with 350VDC for larger applications per many server farm power/battery systems (230VAC switching supplies work at that DC voltage). My own custom off grid system is 120 VDC; no need for parallel batteries or big wire. It's been serving me well for over 12 years now.
Dc voltage above 60v is considered dangerous, and then you need protection for the build which makes it harder in other regards, but yes you also could simply not care.
My comment was about the future of higher voltages for battery banks, but really that is already here.
The Tesla powerwall is already 350-450V. So are their car batteries. I assume they care about safety, as do I. So do Server Farms, who use 350V battery/DC distribution systems.
Many people has been seriously injured by accidental shorts of batteries even at low voltages. There is no magic voltage where safety is assured in spite of unsafe practices and ignorance. 120VAC kills people but is in common use. DC has 4x the shock safety of the same AC voltage; this is a well proven fact. I suggest that 120VDC is a good next step for off grid battery voltage because I use it myself, and 110VDC has a long history of relative safety for home power from back in the Edison days, with bare uninsulated wires on ceramic posts and tubes. As I write this, my computer and rear projection display system with stock power supplies are running directly off of my unregulated battery bank DC voltage; 133V at present. My lighting and daytime cooking are also direct 120VDC, zero conversion loss.
The same safety concern should apply is your typical high voltage PV array, even if feeding a 48V system. Someone with less power safety training than an electrician should not work with higher voltages. I was commenting about the obvious technical future for off grid battery bank voltages. 120VDC is a good, relatively safe next step, in my experience of over 12 years with it. I'm a retired EE and designed and built my own power system. I should probably avoid commenting on public forums for the obvious reasons as illustrated here.
Will does a good job of mentioning safety, and perhaps he should do a separate safety training video. I'm very impressed with the quality of his technical content and presentations. Bravo, Will.
@@brucemccreary769 Anything above 60V is considered dangerous in most countries. DC is not less dangerous than AC, actually it is more dangerous because if you get hit by it, the chance that you muscle keep contracted is much higher than with 50Hz AC where you can still let loose the connection you grabbed, as it is not constantly flowing current but alternating. There are for sure ready build powerbanks which have much higher voltages because of efficency but then they are closed products and not like on this channel, DIY solutions. So if you are talking about finished products, yes there will be higher voltages. If you are talking about DIY you will not get much more than now, this is voltage of 48V LiFePO4 which fully charged is nearly 60V is not just an accident. It easy to raise the voltage, put more cells in series, but the danger of serious injury also raises. This does not mean that you cannot simply do it if you feel yourself comfortable with, but i think you should not expect a public youtube channel which has thousends of viewers present possible dangerous solutions.
Alas, your information on the ""can't release"" safety of AC vs DC is absolutely wrong.
You can easily confirm this at any reputable engineering or physics web site. Try AC vs DC safety in google. DC is 3-5 times safer at any given voltage, and the "can't release" voltage is higher with DC, not lower. You might want to actually learn something about electrical safety before further posting.
As long as the conductors are large enough to avoid voltage drop across the batteries it doesn't mater which way you wire it.
Wow that is what I thought would happen, but it is always awesome to see it in action!
I think the best way to connect the batteries is Posts or functionally identical short Bussbars, what I mean is that you have equal lengths wires either stacked directly on top of each other in the Posts configuration (but that would require alot of torque) or alternatively use the exact same wires to connect everything to a copper bussbar that is only spaced apart enough to fit the lugs next to each other. That way you have the advantage of Posts but you have much more surface area touching each lug, because a lug to lug connection is never perfect.
that is why I have a copper pipe 1/2" flattened and drilled hole to equally distanced batteries. There is only one screw in point. And opposite take off +ve and-ve 3x200 ah 12vdc in parallel
@@leopoldpoppenberger8692 copper pipe is a good cheap way to get started. May I ask how you attach your lugs to the pipe? Is it bolts and nuts sandwiching the lug to the pipe or is the pipe threaded and you are tightening down to that?
If you were to ever upgrade your inverter you should definitely increase your system's voltage. Get a 4th battery and wire them all in series to get 48v that would certainly increase your efficiency. If you are also using 12v appliances then just use a 48v to 12v DC-DC converter.
I think using large gauge wire with the correct size lugs for your terminals and figuring out the best order for the packs would work great. If the lugs are too wide trim problem side or sides and hook it up.
@Jason Morgan
Exactly- I’d have just trimmed the terminals on the grinder.
I tried that and it still pulls more from batteries closer to the load. As Will mentioned in the first video on this, it’s when you start pushing towards the output limits of the batteries that this issue arises. In that case the cost/size of the wires needed gets excessive. I’m going with the Victron image (third one) with the “posts” configuration, as I don’t have rack mount batteries. I’m using small free standing bus bars from Amazon to hook the batteries to the inverter, and the same for the charge controller. The bus bars are going where the big dots are where the four leads come together in the diagram. And of course, a much larger cable between the bus bars and the inverter and charge controller.
Treasure trove dude, thanx.
You talked about the wires coming from the inverter needing to be equal links going to your distributing block. What about the wires from the distributor box to each battery bank do they need to be the same length as well.
put the terminals on the two middle packs surrounding the center pack for peak cheap balancing :P
I've done just that before, now I see its actually beneficial somehow, all I cared about was symmetry, turns out its also functional! I'd put the two newer packs between the 3 old ones also
It would be nice to see you do the same test with the bus bars.
A very interesting episode. Maybe next time you will show experiments with connecting batteries in series ...
Awesome experience thanks. Since the hotter cables have greater resistance, could this have played a role in the current leveling(ish) out?
Nice video again bro & those wiring looks so massive & is it really necessary to use the high gauge wires or it depends on the what metal we're using?! Just for clarification.
Years ago when I worked in car audio, a common problem was large stereo systems that would call for 200 to 300 amps of sustained current draw, but working with 2/0 wires wasn't always practical. We would instead use 2 2-gauge wires in parallel. Looking at these server rack batterys' terminals, it would seem that if you can stack terminals, this would do the trick. That being said, by the time you bought, cut, and crimped all those cable, it probably would have been cheaper to buy copper bars and drill/file them to fit.
At the 6 min mark, when feeling the cables. Visual thermal imager would be cool screenshot of the pack and cables.
Yeah that would have been awesome. Should have used my thermal camera.
A nice wee torque wrench is needed for uniform tightening of the terminals, takes out the guess work. Split bus bars are the way to go for high current discharge/charge. Nice copper 3/8" thick from the BMS would sort out any resistance issues. With the energy prices going through the roof in the UK 50% INCREASE in April, I think the return of investment would pay for itself in half the time.
I’ve never had an issue with diagonal as long as all the capacities are the same. I just ran a test on a 2P X 16 620ah battery. Did you know that 175 amps on 2/0 cable for a few hours makes a nice hand warmer?
Please note the the current is additive, so the interconnect wires closest to the output is pulling all the current. That is why they are hotter then the other upstream wires.
If you connect the output wires in the middle of the pack, then no single interconnect will take the full current.
Yep that's right
Appreciate your analytics. Ever consider explaining high output alternator charging of lifepo4? I’m considering installing a Nations secondary alternator for my Battleborn bank. But the internal BMS seems to be an issue allowing a complete charge even with a Wakespeed regulator.
This is not true "diagonally connection", because in the "diagonally" the same cable sizes should go through all the connected batteries, but here in your video diameter changed at the edge terminals of this bank (unbalanced connection from begin).
Anyway, thanks for the opportunity to watching so interesting experiments and listening such thoughts!
Please tell us that you are now doing the same experiment with buss bars for us to see!?!? Great video!
Well, thank God for Will Prowse and his NBS (No BullShit) Channel. Here in Puerto Rico the neoliberals are privatizing the grid with LUMA Energy, and we need to migrate, not out of the islands, but to Solar. This is good, practical info. ¡FUERA LUMA!
Interesting experiment but I think a lot of people would say the difference in internal resistance and the difference in capacity would also throw off your numbers at the rate of discharge.
Unless the batteries were all from the same year make model manufactures date of production line then you could be confirmed of accurate numbers
Yes that is what I said in the video
Eliminate your variables, experiment with same batteries to start. But you still have a busbar with 0 resistance connectors, so "busbar" and "diagonal" to the posts is the same setup, electrically, assuming more consistent conductors than you're using.
You want equal resistance from your load to the individual packs. As I mentioned yesterday, the diagonal setup is just the "reverse" of connecting your load to the middle pack. Same issues.
In your setup specifically your positive load conductor is very different from your negative load conductor as well as between the packs.
Get out your Fluke and have fun getting it properly balanced. It'll be instructive for all
Once a company sends out 6X of one type of battery, I will. And I bet I can pull within 1% of each other once I have that set up. Will do so in the next few months
@@WillProwse It should be fun, and great to watch.
I will make a pack with 6X matched server racks with equal length conductors. Should work great.
@@WillProwse Equal resistance conductors, yes
Brilliant
Thanks for the video Will. I was interested to see what happens when you get to 0% SOC on this setup.
Do all of the server rack batteries shut down at the same time or,
do they shut down individually till only one is left to supply the whole load and it shuts down because of added voltage drop or overcurrent protection.
If you look at the charging curve on a TESLA MODEL 3 with LFP what was called the SR+ especially in colder weather, it starts out building the kW quite slowly then ramps up later but for longer than NCM etc on an LR or Performance.
This is awesome! I'm about to rewire a sailboat and this info is what I was thinking about. Bus bar for sure. I'm just curious, with cells is series, is there a difference in the amperage drawn from each between the end and inner batteries?
so entertaining... mind blown
The way I solved the problem is I ran a second cable from the first battery, to the last. It not only improved charging, but discharging as well.
Another good video will!! I particularly liked the discovery that the imbalance is much less when the batteries are in the flat part of the charge curve.
A few points:
1) If there are only 2 batteries in parallel, they will stay balanced if you hook them up diagonal. Each additional battery above 2 will create more imbalance even with the diagonal hook-up.
2) If you use long bus bars as shown in the picture in the video, they need to be sized fairly large in order to minimize the voltage drop across the bus bar, otherwise you will get the same problem you are trying to avoid.
3) When making the cables for the battery hook-ups, each crimp is important. If one of the crimps is not perfect, it can throw off any attempt to arrange the batteries for balance.
Along these lines, server rack batteries should be designed so that when they are racked up you can bolt busbars directly on the battery terminals to interconnect them. The Jakiper batteries in the video would not handle this well because the bus bar would have to be narrow and one of the busbars would cover the controls. The un-named batteries look like they might handle direct connection to the busbars better but I would prefer to be able to put wider bars on. If you used two thick bars on the un-named batteries it might work well.
4) When doing busbars, it is important that they be covered for fire safety reasons and electrocution safety on 48V systems. I like putting heat-shrink over everything except the connections, but there are other techniques like mounting plastic covers that can be removed when servicing....... Hmmmmm that would be an interesting feature on a server-rack battery: Snap-on Plastic bus-bar covers that are the height of the batteries.
1) Rack up the batteries
2) Bolt on the busbars
3) Snap on the covers
*** Done ***
That's exactly what I did at my last battery install, got 400A flexible insulated busbar, drilled holes, cut the insulation and bolted them in - 5 batteries connected to 3 inverters, no hassle. "CFX1045" from electromechanica
Agreed!! Good points
The signature solar rack has plastic covers over the buss bars. They appear to be the plastic raceway and covers you would see/can install in a server rack.
um, even with 4 or more in parallel diagonally, if the inter-battery wires are the same gauge and length on both plus and ground, each battery sees the same total wire resistance on + and - combined. say each jumper is 10 milliohms, and your plus feed cable goes to B1, with the - ground cable to B4, then B1 sees 0 extra milliohms on + but 3*10 on ground, B2 sees 10mOhm on + and 20 on -, B3 sees 20 on + and 10 on -, and B4 sees 30 on + and 0 on -... so each battery has the same 30 milliohm in series with it.
I definitely agree re crimps, but with proper fine strand pure copper welding cable and a decent hex crimper and using the same pure copper ring fasteners, the crimps should be very consistent.
@@geepeercesYes, diagonal is better than nothing but it is *not* balanced beyond 2. If you have more than 2 batteries in parallel and use diagonal to hook them up to the system, the outer 2 will carry more load than the next ones in and so on. That is what will just demonstrated in his video. The higher the load, the worse it will be. This was worked out years ago with lead-acid and holds true with LiFePo4.
It is interesting that in the flat part of the SOC curve the effect is less pronounced than when the batties are fully charged, but the effect is there nonetheless.
Will...you need a bench grinder, so you can fit your cables in narrower terminals when needed.
I would like to see a test with the bus bars.
Hey good video, I was wondering are speaker cable any good to use in battery bank for solar?
you could always grind or file the sides down slightly on the ring terminals to fit on the battery terminal strips...
thanks for these examples, will you be doing the same test with a bus bar so we can see the results there?
Appreciate the lesson on options. I wonder how the battery balance would turn out if the main cables were connected to the middle (lower volt reading) battery. ... That might be worth a test on that specific battery set. ... just some thoughts
Grat video. I think that the size of the wires in between the packs is important. In here we have thicker cables on each end of the string but thinker cables between the individual banks. If all the wiring was done with the thicker cables we would have more balanced results ( proportional to the capacity) as the resistance on the hotter thin wires would be smaller.
But we cant. Did you see the video? The max you can add on this terminal is 2 gauge. These batteries come with 6 gauge wires. That's a huge reason I made this video.
@@WillProwse yes I've seen it and I understand why you have done it this way. You can do this by filing the connectors so it fits. I didn't see the surface too close so can't calculate exactly how big the connection surface is there and whether enough for 230 amps of current but I think it was worth asking. I know that it is never good to tamper with the connections but you are wire enough to do it safely ;)