Nice video. This is a pretty simple concept, but I have not seen it explained so well by any other TH-camr. Very good job. I just ordered 8 206ah cells and 2 200a JBD BMS's directly from China. I mulled over doing a 4s2p with one BMS, or building 2 4s batteries paralleled together. I diagrammed my wiring on paper and was sure it was correct, but I was looking to confirm it. The last part of your video did that perfectly. I also wanted to use my smart bluetooth BMS's to monitor all the individual cells. With 4s2p you can't do that. You explained it so well and confirmed the extra money I spent was well worth it. Thanks and cheers.
WOW....Thanks to this forum and TH-cam I was able to build a 271ah x2 battery. Testing with various loads that will be in the van build. This is really exciting to know that I have saved so much money on drop in batteries.
Great explanation and reason as to the benefits of both layouts. You have convinced me to do your preferred configuration. Will just have to purchase 2 bms. Thanks
Thanks for the video. I do separate series strings as well and then parallel the strings together onto a main setup of buss bars that the inverter, charge controllers...etc... connect to. The added benefit for me is that I can have a separate longmon for each cell for the batrium bms.
You only have 2k subscirbers, but I do believe you can easily have 200k+ if you do those videos more often. Seen enough youtube over last 10 years to know you will be succsefull if you stay consistent :) Thanks to this vid, I will be probably dropping my 250a bms 4/2s config I was planning, and get 2x 150a bms and just do 2x 4/1.
Hey thanks man, I appreciate your comment. I started this channel just for the fun of it, and now that it is actually doing moderately well I've got to decide how much time to devote this hobby of mine. We'll see, but supportive comments definitely help.
Great Video, we've seen tons of video's, however, yours sir are the BEST....Simple and to the point, and believe me, us newbie's really need it simple. If I wanted to add one more battery to your last demo, I would simply connect the other one to the main neg & Pos as you described with your last demo, correct ? thanx Jerry
@TheWilltoBuild When connecting 2 batteries in parallel (your favorite setup), do you short the negatives and connect the BMS's to this, or do you let the BMS's being the "busbar" so there is no direct short on the batteries?
Wow, Your such an angel sir😅 im planning to build a 12v lifep04 (on a smaller batteries but finds the ah rating pretty low. This will doubled my needed ah rating. And yeah 2 BMS for me too. Thank you so much sir🤩😊👍
Thanks for a great video! I like the parallel option and just checking if all BMS' can support this option? I'm planning to use the JK-B1A8S20P on each battery.
In the first scenario, if one cell dies, the BMS should shut off from overcurrent into the other cell. Actually, the more cells you connect in parallel, the least the current per cell and the more reliable each cell operates. This holds true for both scenarios, but the second scenario adds the reliability, variance of MOSFET or voltage detection ICs and increases the cost of BMS's. However, paralleling more BMSes is a MUST once the load current exceeds the BMS spec. I have only one ANT 320A(max) BMS on my 16S40P LiFePo4 batttery and it works great. My 40P is actually 5x 8P of A123 round cells. But prismatic cells are made with multiple pouches in parallel too. This being said, having your system uptime uninterrupted is nice, but you operate only at a fraction of the total load power, which might not be optimal in certain situations. Ill be expanding my bank this Sept with 16x EVE-280Ah prismatic cells which I plan to hook an another BMS in parallel for uptime like you suggested, althought my current BMS is largely sufficient for my loads
Thank you for this video - I would much rather have individual cell monitoring since this thing will be under our bed. Unfortunately, our battery location fits the rectangular 4S2P best but I will be going with two batteries / 4S configuration. I will just use wiring for the interconnect instead of bus bars. Using two Overkill BMSs.
Great video! How important is it, that the two bms are identical? I have a bms I bought a year ago - not certain I can get the exact same version again.
I have 8 (3.2v) lifepo cells and needed to increment both amps and voltages. I went for your guide on 8s2p but I don't know now how to connect the BMS since I have an 8S bms that I was previously using in series. Now since they are both in series and parallel I'm a bit confused on the wiring
@@TheWilltoBuild there are a lot of TH-cam posts about problems with getting good connections with these cells. Any poor connections with a parallel pair will result in the pair becoming unbalanced and the pair/pack capacity will suffer. Having 2 strings of 4 would mean more BMS connections but each cell would be monitored and any imbalance between strings due to poor connections would be much more obvious. There is another youtuber who is putting together a battery, 3P16S I believe, and it will be interesting to see how that goes.
Great video. It’s probably worth mentioning how your amperage requirements play into which configuration is viable as well. If I’m powering a 3,000 watt inverter, a 4S2P with a 12v 120amp OverkillSolar BMS won’t work because the BMS max output would be 1,512 watts. You’d need a 250amp BMS or two 120amp BMS wired in parallel to get you up to 3,000 watts (or whatever your load requirements are).
Another good video! Much appreciated, very well explained. What I have been looking for, being a newbie, - and there is an overwhelming amount of information out there ( too much) is a series of LiFePO4 videos, well linked together.. that answer the question - OK, I got my batteries finally, now what? What is a step by step procedure for Connecting in series vs Parallel ( thank you!) How to charge your batteries ( thank you again for your vid on that) How to balance your batteries ( thanks!) How to measure their capacity How to discharge them How to hook up a larger BMS w details Not sure what else, or in what order... Just my 2 cents
Thanks for the video, especially for making it understandable. I was thinking i wanted two separate banks for the scenario you covered at the end, if something happens with one bms your screwed, with two you can still have power with one bank. My question is, what size bms to get? I see the daly being used with lifepo4 banks and they seem durable, Will prowses milk crate build is about what im thinking of doing. I did see another van lifer video where he added some heating pads and sensors since he was in the cold weather, and being from michigan i may watch that build again to add the heat pads. The cold build used a 80 watt bms and Will used a 250. It seems like a big difference, and neither used two banks in parallel which i will be. I think it was about 15 mins in on your video where you covered it, but didn't mention the bms you would use and how you would run them together. Any chance you could give me your recommendation on the size bms, I'll be running a mini deep freezer and a 5,000 btu ac, with just a few lights in a cargo trailer with 4 200w solar panels on the roof. I was impressed with the max output of the 250 Will used so seeing im going to run an ac, should i go to the larger bms to be better safe than sorry? My apologies if this is rambling lol, but i appreciate any recommendations on sizing and how to configure them together. Thanks!
This is a good question. Always go for a big BMS. Most of the cheaper ones say they are rated for a certain capacity, but in actuality really can only do like 80% of that, so oversize them. I've been using Daly 250 amp smart BMS. It wasn't easy to get it working properly, but it is working now. Otherwise there is overkill BMS as well. But everyone is out of supply right now unfortunately.
I was able to acquire a 96kw Absolyte GX (2 volt) series battery bank. Have you ever worked on something like that? I need to wire 24 cells into 48 volt configuration for a 48 volt off grid system. I'd appreciate any assistance if you had some time to assist. I'm also wondering if it is possible to utilize a BMS on this size to constantly monitor the entire bank. Thank you so much for your videos! I have subscribed - looking forward to watching your old and new videos!!
Hi, the Daly BMS link is for a BMS on Amazon that is for the 18650 batteries. Will that work for the large cells you are using? Sorry for the newbie question and thank you in advance for your response.
BMSs don't care if the batteries are 18650 (cylindrical) or the big ones I am using (prismatic). As long as you can correctly wire them to the battery, they will work fine. BMS care about the chemistry of the cells, not the shape of cells. Good luck!
@@TheWilltoBuild Hi and thank you so much for the response. I noticed the one you had a link to was so much cheaper than other ones I have looked at that I was hoping it would work. I am looking to build a 4s 12v 200ah battery so .. pretty basic and was hoping! Thank you!
Ok I have an RV with one 100w solar panel one charge controller and two agm 51ah 12v batteries and one 12 deep cycle ah unknown lead acid battery what would be the most efficient way to install these so they charge and supply 12v to my system? Please and thank you
My build 4s 2p sir and the battery next to negative main is the one who charge full 1st then next one beside the main positive is the 2nd to charge full and the main negative and main positive remain to 3.37v. My active blancer is 4s 5a and 60a discharge/30a charge current bms. My problem is i can't balance them when charging on solar panel before i assemble them i do top balancing 1st. Hope you can help me or i will just follow your advice which is 2 bms
I plan to do a van conversion build. I have been looking everywhere on youtube for this sort of video. I want to have 2 DIY batteries made up of 280ah cells from aliexpress, and these batteries i plan on connecting in parallel and hope to run 12volt appliances from it and also a 2000watt inverter. I want to have a 250amp rated Daly BMS on both of the separate DIY batteries. I need to do more research on solar charge controllers and DC to DC charging and all that stuff but... Can you see any holes in the rough idea I have? would appreciate your feedback
Honestly it sounds good to me. Doing two 12v batteries, both with a separate BMS, sounds like a good idea. You could also just do a 24v system and use a converter to run 12v appliances, but that may be more trouble than it is worth.
@@TheWilltoBuild thanks, how long have your 12v DIY battery systems lasted ? Are they holding up well ? Also have you had any experience with the 310ah ones... I trying to figure out if it is just fake advertisement from aliexpress
Hi I'm new to the lithium game and I am into car audio and I have just purchased 8 3.2 90ah cells like in the video and just wanted to see if you could make a diagram of how to wire them in 12v 180ah thanks and like your videos
Great Video.. Could u please clarify your note, why not main negative? Is the black and white reversed? I would have thought white was positive. Could you please show a 2 bms setup not work all cells in one long line rather than in a square format. Thanks
This basic BMS does not. No communication at all - which is true for most basic BMSs. More sophisticated BMS do have communication options, most often by bluetooth.
This is possible and will work fine. I have heard of someBMS makers tells people to not do this, but it is really unclear why this should be an issue. If you do two separate 16s batteries, give them each their own BMS, and then put them in parallel, it shouldn't have an issue unless the specific BMS is weird (so maybe check with the maker?). After all, many off the shelf batteries have a BMS (like battleborn) and you can wire those in parallel no problem.
@@TheWilltoBuild so I too have a16s bank x3 each bank is 48v100ah (so that is 48 batteries at 3.5v 100ah) i have a 16s killwat bms. My ? Is if i use the 16s bms can i still wire my batteries in a 12vx4 =48v or do i need to wire all 16s to = 48v and keep the 100ah for each of the three banks. I would like to at least go from 300ah to 600ah. Any help is greatly appreciated thank you.
Hi great posts best I've seen. I'm a newbe Interested in building 4x4sp (3.2v 105ah) to create 48v. I assume l can repeat your 8 cell example with 4 bms
Can u tell / show how can I make a 48 v battery but with like 600 ah or more? I’m gonna buy 16 of these and I need 48 bt I also need higher ah because 280 is not enough
If you run 2x 100amp max discharge bms on the batteries for your preferred way of setting them up are you still capped at 100amps discharge or does it become 200amp discharge
Congrats very well explained. My question is can you use the same process to wire Lead Acid batteries in series and parallels and at the end close the loop before connecting the Negative and Positive wires to the Inverter or leave it open witch one is better? Thanks
You can wire lead-acid batteries the same - in terms of the basic wiring. I don't quite follow what you mean in terms of "close the loop". You do want to ever directly connect the positive and negative wires. That is a short circuit which can very quickly hurt you and the batteries.
Hey, great video and Thank you for putting it out there. New to batteries and electrical systems but i'm learning a bunch. Had a quick question. Can we use the DC power supply as our main charger to charge up lifepo4 cells batteries or are they only use to top or low balance the batteries. I don't want to buy another charger if it's not necessary. thanks for your time!!
You can definitely use your bench power supply as your primary charger, it just might be kind of slow. Also, most cheap bench power supplies only go to 30v, so won't be high enough for 48v systems. But...I have used two bench power supplies in series to charge a 48v battery.
@@TheWilltoBuild Okay, Thanks! I have a 12v system with a 200ah battery. if it's charging at 10ah max, it would take 10 hours to charge up 100ah, correct? That's what the charger is capable off, right. Just wanted so confirmation/clarification. thanks again for your time and response!
@@stevensam8834 Yep - in theory you could charge the whole thing in 20 hours - but the rate of charging will slow dramatically when it gets close to fully charged so it will take longer than 20 hours (more like 30).
Good explanation and a cogent argument made. From an efficiency standpoint, a 24v, 8S configuration, with the proper BMS and 24v inverter, will deliver more power, correct?
Functionally, 8 cells can deliver the same power whether they are 4s2p or 8s. The 24v system has higher voltage, but the 4s2p can push more amps. That said 24v is still better in my opinion. Cells prefer to be in series, and 24v systems will need smaller wires and will be more efficient with an inverter.
@@TheWilltoBuild - I was basically referring to the efficiency ratings for the inverters. 48v is better than 24v, which is better than 12v. If the use-case is off-grid or emergency backup, the 24v, 8S configuration, paired with an appropriate inverter, will deliver more power with less conversion loss.
i watched this video and have a couple of question: 1) can you show or explain once i have connected the two sets of lifepo4 ( mine 3.2V, 200amh) batteries in series then connect these sets in parallel how are the BMS connected together to go to 12v fuse panel and charger. 2) Can you suggest what size BMS(2) i should use, would (2) 4s 12v 100a be ok to use?
Hello! I need some help with wireing my first lion battery pack. Ill have 6 4s lion batterys in parrallel, so i get 24 volts and 90000 mah. Because 3400mah*24 lion batterys is about 90000, or isnt it? I dont know, thats why i need help. Also, how do i wire them up, do i put the 4 cells in parralell in series with the next one?
Hey, I'm having a little trouble following your question. I think your amperage calculation is correct, you have a total of about 90 amps, but it is not the correct way to think about the batteries. What are you trying to do? Create a 24v battery? Do you know what type of cells you have? Are they lion or lifepo4?
@@TheWilltoBuild Aha, ok, i understand. I wrote really crappy english, i was very sleepy. I want to make a 24V lion battery for my diy bluetooth speaker. It needs to be at least 90Ah to last 9 hours. Its a big ass speaker! I need to wire 4 18650 batteries in parralell, and then use 6 of those to get a total of 24 volts. The only thing is that i do not know how to wire them up. How do i wire the 6 cells in series to get 24 volts? Best regards, Linus.
Im new to the idea of lithium for my car audio endeavors. But does anyone know if i could get these for my truck and use them as a battery bank my max amperage pull would be about 800amps and ive got a 280amp alternator and gonna get 2 500amp switches for them. would i also need to get some sort of charge controller cause i remember charging is a big thing to try and make these things last.or should i just forget about it and get a couple deep cycle XS batteries.
I made my 4s battery last night, and when I hooked up to the charger, I got sparks. All of my previous connections seemed good, but then I couldn’t charge the battery. Any idea what I may have done wrong?
Hmm, there prolly should not be sparks. Are you 100% sure the battery is wired up correctly? Also, did you attach the right leads from the charger to the right places on the batter (positive with positive, negative with negative)?
thansk sir for explaining please I have question is it healthy if I connect 4 sales parallel and connect themes on seris and following the rest on seris like I have 50 CELLS ON seris and 4 parallel can I link it on seris to each other the 4 cells parallel withe the 50 cells on seris
Sure. Set Screws, item number 8740: www.boltdepot.com/Metric_set_screws_Allen_Cup_point_Stainless_steel_18-8_(A-2)_6mm_x_1.0mm.aspx?Selected=8740 Serrated Nuts, item number 12009: www.boltdepot.com/Metric_flange_nuts_serrated_Stainless_steel_18-8_(A-2).aspx?Selected=12009
I am wondering if I can connect a 12volt 200ah prismatic cell battery in series with 2 12 volt 100ah lifepo batteries in parallel to get 24v 200ah ? so there are 3 batteries total. 2 identical batteries in parallel for a 12v 200ah, with 1, 12v 200 ah. I understand its a less than ideal to put unlike batteries together but can it be done? I tried to do it but got a huge spark attaching the 2 parallel ones to the 12v prismatic. negative to positive and positive to negative. any suggestions ?.
Really good question. I'm not sure actually. I think they should be good for 50 amps at least, but I expect much more. But I'm not an expert in this will have to do more research. Great question!
When you connect 2 4s batteries together is it best to draw power from the bank by connecting to a negative stud on one battery and a positive stud on the other battery?
You mean together in parallel? Generally speaking both negatives should do to a bus bar and then both positives should go to a separate bus bar - and then you wire your system off of the bus bars.
@@TheWilltoBuild Sorry I wasn't clear. Yes in parallel. So you advise using busbars for even just a 2 battery bank? I see the advantage for a 3 or more batteries in parallel because it will facilitate an equal draw from each battery, but I am not so sure its worth the expense for cables and stud busbars for only 2 batteries. Any comment on that?
@@michaeldoherty2289 You just want to make sure you are drawing from each battery equally. You could potentially just improvise something, perhaps connecting a wire to each positive terminal (for instance) and then connecting that those two together at a third wire that serves as the total battery positive. All you would need for that is some wire, some crimps and a stud with a washer to tie them all together. If you go to your local hardware store of HD or Lowes and go to the electrical section, you'll see alot of stuff that can allow you to pretty cheaply connect three wires together.
@@michaeldoherty2289 You just want to make sure you are drawing from each battery equally. You could potentially just improvise something, perhaps connecting a wire to each positive terminal (for instance) and then connecting that those two together at a third wire that serves as the total battery positive. All you would need for that is some wire, some crimps and a stud with a washer to tie them all together. If you go to your local hardware store of HD or Lowes and go to the electrical section, you'll see alot of stuff that can allow you to pretty cheaply connect three wires together.
@@TheWilltoBuild OK. To follow up on this further I have one more question. Say I have 2 separate 12v battery packs just like the 2 at the end of your video. If I install a 4s BMS on each 12v battery. Then to parallel them I simply connect the 2 main 12v positives together with 2 equal cables going to a single post terminal. This will become the main positive battery terminal. Then connect the equal length P- leads from each of the 2 BMS's on a single post terminal which then become the main battery negative. This all happens inside my battery box (which contains both 12v packs). This way I do not have to connect the 2 12v packs together with solid busbars (the ones you said you didn't have long enough busbars to do that in the video). It totally resolves the question of which terminals become the main terminals when the 2 12v packs are connected with 2 solid busbars. It also assures that each of the now paralleled 12v batteries (or really all 8 cells) will be equally drawn upon during use. Is that clear and is that correct?.
I have a 4 battery lifepo4 24v battery bank with 12v batteries in series parallel connection . Problem is the 2 batteries that is connected to the inverter get 15,2v charge while the 2 other batteries in the series connection that is not directly connected to the inverter is normal 13,3v, total voltage is 28,5 for both battery banks. I have a battery balancer but it only balances the voltage of the 2 banks, not the 2 batteries that get way to high voltage charging. It seems to me after what I have read about electrical engineering that to not get over voltage on the batteries that is directly connected to the inverter you have to have exactly the same resistance, meaning equally long vires to all the battery connections... But I have not see anyone ever doing series parallel connection that way. Everyone connect it like I have done with charging and inverter directly connected to 2 of the batteries in the series parallel battery bank and the 2 last batteries connected with longer wires.
If I accidentally put the bus bars on wrong for a few seconds when I first got the batteries to “short” then. Did I permanently damage them to the point that I rendered them useless?
Hello, Please I have this INVERTER Growatt 5KW 48V 220V Solar Hybrid Inverter SPF SPF 5000TL HVM-WPV-P Max PV Input Voltage 450V MPPT 100A Solar Charger Can Par . Please can you show me what type of battery I will need to run this?
What happens 8f you have terminal 1 with positive and a neggative leads aNd terminal number 2 are the same both coming out of my mobility scooter I was fine till I realized I had two two of the Same terminals
OK I like the way you did it. I have 1 question I have two BMS but one is 4s 12v 100A and the other is 4s 12v 120A both are made by Daly. Can I still use those two even tho they are different in Amps?? Thank you.:)
Good evening LtB... I have an unrelated question that you may wish to answer..? I have two solar generators and would like to power both at the same time using one 180 watt solar panel (instead of a separate for each).. Realizing that the sogens cannot be connected together in any way, my solution would be to provide the necessary branch mc4's for each sogen and isolate each branch with an inline mc4 fuse which already has the diode built in to prevent vdc back charging. Your thoughts..??
I really can't say I've ever encountered anything like this, but my feeling is that feeding two separate solar charge controllers with one panel is a bad idea. I would suggest just adding another panel and having them be completely separate.
@@TheWilltoBuild "feeding two separate solar charge controllers with one panel is a bad idea".... Why...??? If each pos leg has a blocking diode in the inline fuse to prevent back feeding to each other across the mc4 branch (which acts as a voltage divider) and one sogen from charging another...? I already know that I can connect one to the panel and the other to the ac inverter...
One good tip that I haven't seen others do is take a strip of masking tape and paint (spray gloss enamel, etc.) it red and let it dry. Then cut it into little squares and affix a piece to the top of the cell next to each of the positive terminals. It elimates all confusion as you are rearranging or working with the batteries. Never second guess which is the positive terminal. I also mark each cell's number on the red tape, (1,2,3,4,...) For the cells in order. Also I number the balance leads with tape as well. I love your long studs, are they Stainless? Which length did you go with?
Great advice. There really is no harm in being extra careful and it would be very easy to make a mistake. I get the set screws (studs) at the bolt depot, and in this case the are 40mm. In hindsight I probably could have gone a bit shorter.
hi i build my first electric trike using fiat 500e lithium battery packs each pack is 24v i use 8 packs in series for 200v but i have 2 24v packs left over i would like to parallel these two packs and use them as a range extender to the end of my 200v pack is this possible. my pack of 200v all get charged and balanced individually so one pack of 24v to one charger . will this work for range extender.
I have 2 separate 4s cells batteries . With the b- going to the main negative on the first cell. SO do I wire from one c- to the other c- and have the main negative come off of that?
Can I hook the two 4S batteries up in parallel with separate BMS and charge/discharge them with a single source safely & efficiently? Or do I need some sort of third system to monitor the combined batteries in parallel? What happens if I only use one half of the system individually (I take it with me as a portable power source) and the 4S batteries are then at different charges? I need to charge them both to max again before connecting them in parallel, right?
You can definitely put two 4s batteries in parallel with one another, this is very normal and shouldn't be an issue as long as they are at the same voltage. If you put them in parallel when they are different voltages, it could be a big problem. If the difference in voltages is large, LOTS of power could flow from one battery to another. Try and match the voltages between the batteries very closely. They don't have to be identical, but pretty close (I would say .25 volts or less).
Great, thanks@@TheWilltoBuild ! What about using one battery more than the other over a longer duration? If you link them, you would potentially bottle neck the less used one since the more frequently cycled one would hold less wh, right? So I should try to cycle them equally over their lifetime?
@@TheWilltoBuild Hi, like to follow up on this one. Cause, I have 8x 105AH EVE's on the go. 12V system is mandatory and I consider 2 individual batterypacks to be comfy. I'd like to understand what's going to happen exactly, if I stress them separately and connect them to 210AH 12V intermediate ? Let's assume to use generous connectors as well as both have each a 60-80A BMS. Won't the BMS'es amoung themselves manage/restrict to settle "the situation" ? Elsewise any suggestion how to solve this, may with ?relay? Setup should be for a camper van: charge with cars alternator & solar on the roof Battery1 and go fishing with Battery2 to run a boat engine.
@@TheWilltoBuild exactly what i want to do.... following your example above... but doubling it... do i then just continue the main + and main - horizontally .?
I don't have two BMSs to show unfortunately, but you would just wire the positives together, and then also wire the P- from each BMS together. Then, to connect to the inverter, just connect the inverter positive to the positive of both batteries, and the negative from the inverter to the two connected P- from the inverters.
You do really explain well!!! Kudo's!!! I recommend you rather "voice-over" your videos from a script (not ad-lib) to avoid small errata ... (e.g. you mention 580Ah in stead of 560Ah.); alternatively get voice recognition software and read from the translated script. As an engineer, I completely agree with assembling 2 x 12.8V batteries each with their own 4S BMS in stead of 1 x 25.6V battery with 1 x 8S BMS !!!
Yep, he's right. You can't use an 8s for 4s2p. You can either do one 4s2p combined battery with one 4s BMS, or two 4s batteries with separate BMS and wire them in parallel. But if you can run a 24v 8s system that is best and do that!
@@toastiesvanbuild4644 I think it is bad idea to do it for any extended period of time. If they are genuinely in parallel, the larger battery will constantly be charging the smaller battery, so for every charge and discharge cycle, you are going to work the small battery twice. Generally speaking the battery community this is seen as not advisable.
Really need to know why you said you would not recommend Two different brand batteries in the same bank..or why mixing Energizer and Duracell’s is a big No no so to speak?
Just because different brands are likely to have different capacities and different behaviors, in particular internal resistance (IR). If the internal resistance of the cells is different, then some cells will charge and discharge faster than others. That extra work will age the cells faster, and then they will have different capacities - which will also cause them to charge and discharge faster and wear them out even more! This is actually a good video topic.
@@TheWilltoBuild , I don’t believe there is any hard data that supports this preposed you tube theory, I have heard other videos repeat this information over and over in explanation but lacking data to support this. That’s exactly why I used the two different batteries as a example. IR is easily measured and would more than likely be so minuscule that it would not be notable even in 1000s of cycles. However the proof is always in the pudding. It would Be a great experiment…
@@Mellosucc3ss 32 cells 8s 24v 4 parallel x280ah =1120ah 500amp BMS, advantage is that with large loads one 24v battery failing could cause the other exceed their rating. Each block of 4 self balances meaning you're less likely to under/over volt one cell. Its also the way Tesla build their packs but they then series connect those packs 😮
Nice video. This is a pretty simple concept, but I have not seen it explained so well by any other TH-camr. Very good job. I just ordered 8 206ah cells and 2 200a JBD BMS's directly from China. I mulled over doing a 4s2p with one BMS, or building 2 4s batteries paralleled together. I diagrammed my wiring on paper and was sure it was correct, but I was looking to confirm it. The last part of your video did that perfectly. I also wanted to use my smart bluetooth BMS's to monitor all the individual cells. With 4s2p you can't do that. You explained it so well and confirmed the extra money I spent was well worth it. Thanks and cheers.
So glad I could help!
WOW....Thanks to this forum and TH-cam I was able to build a 271ah x2 battery. Testing with various loads that will be in the van build. This is really exciting to know that I have saved so much money on drop in batteries.
Awesome stuff. The savings are immense, same reason I went down this rabbit hole myself.
Great explanation and reason as to the benefits of both layouts. You have convinced me to do your preferred configuration. Will just have to purchase 2 bms. Thanks
Been searching for hours for exactly this info on parallel batteries! Thanks
Thanks for the video. I do separate series strings as well and then parallel the strings together onto a main setup of buss bars that the inverter, charge controllers...etc... connect to. The added benefit for me is that I can have a separate longmon for each cell for the batrium bms.
You only have 2k subscirbers, but I do believe you can easily have 200k+ if you do those videos more often. Seen enough youtube over last 10 years to know you will be succsefull if you stay consistent :)
Thanks to this vid, I will be probably dropping my 250a bms 4/2s config I was planning, and get 2x 150a bms and just do 2x 4/1.
Hey thanks man, I appreciate your comment. I started this channel just for the fun of it, and now that it is actually doing moderately well I've got to decide how much time to devote this hobby of mine. We'll see, but supportive comments definitely help.
You answered questions I’ve been looking for long time! Thanks a lot!
Great, loved your explanation. Greetings from the Netherlands
Great Video, we've seen tons of video's, however, yours sir are the BEST....Simple and to the point, and believe me, us newbie's really need it simple. If I wanted to add one more battery to your last demo, I would simply connect the other one to the main neg & Pos as you described with your last demo, correct ? thanx Jerry
@TheWilltoBuild
When connecting 2 batteries in parallel (your favorite setup), do you short the negatives and connect the BMS's to this, or do you let the BMS's being the "busbar" so there is no direct short on the batteries?
Wow, Your such an angel sir😅 im planning to build a 12v lifep04 (on a smaller batteries but finds the ah rating pretty low. This will doubled my needed ah rating. And yeah 2 BMS for me too. Thank you so much sir🤩😊👍
Great video, I only bought 1 BMS 😢 Definitely want to monitor each individual cell. I will run it with 1 BMS for now, and save up for another one 😂
Thanks for a great video!
I like the parallel option and just checking if all BMS' can support this option? I'm planning to use the JK-B1A8S20P on each battery.
In the first scenario, if one cell dies, the BMS should shut off from overcurrent into the other cell. Actually, the more cells you connect in parallel, the least the current per cell and the more reliable each cell operates. This holds true for both scenarios, but the second scenario adds the reliability, variance of MOSFET or voltage detection ICs and increases the cost of BMS's. However, paralleling more BMSes is a MUST once the load current exceeds the BMS spec. I have only one ANT 320A(max) BMS on my 16S40P LiFePo4 batttery and it works great. My 40P is actually 5x 8P of A123 round cells. But prismatic cells are made with multiple pouches in parallel too. This being said, having your system uptime uninterrupted is nice, but you operate only at a fraction of the total load power, which might not be optimal in certain situations. Ill be expanding my bank this Sept with 16x EVE-280Ah prismatic cells which I plan to hook an another BMS in parallel for uptime like you suggested, althought my current BMS is largely sufficient for my loads
Excellent video ty! Hey can I use these cells with a super cap bank too? It's a 18v maxwell bank I charge at 14.5
Thank you for this video - I would much rather have individual cell monitoring since this thing will be under our bed.
Unfortunately, our battery location fits the rectangular 4S2P best but I will be going with two batteries / 4S configuration. I will just use wiring for the interconnect instead of bus bars.
Using two Overkill BMSs.
Great video!
How important is it, that the two bms are identical?
I have a bms I bought a year ago - not certain I can get the exact same version again.
I have 8 (3.2v) lifepo cells and needed to increment both amps and voltages. I went for your guide on 8s2p but I don't know now how to connect the BMS since I have an 8S bms that I was previously using in series. Now since they are both in series and parallel I'm a bit confused on the wiring
Great clear presentation.
A 4S2P IS the better option, as opposed to a 2P4S, but you’ve overlooked a very important problem with a 2P4S configuration.
Which is?
@@TheWilltoBuild there are a lot of TH-cam posts about problems with getting good connections with these cells. Any poor connections with a parallel pair will result in the pair becoming unbalanced and the pair/pack capacity will suffer. Having 2 strings of 4 would mean more BMS connections but each cell would be monitored and any imbalance between strings due to poor connections would be much more obvious. There is another youtuber who is putting together a battery, 3P16S I believe, and it will be interesting to see how that goes.
Very clear and nice video thanks mate good job 👍🏼
Great video. It’s probably worth mentioning how your amperage requirements play into which configuration is viable as well. If I’m powering a 3,000 watt inverter, a 4S2P with a 12v 120amp OverkillSolar BMS won’t work because the BMS max output would be 1,512 watts. You’d need a 250amp BMS or two 120amp BMS wired in parallel to get you up to 3,000 watts (or whatever your load requirements are).
That is a great point and actually a good topic for a future video.
This guy explains things so well. Thank You Sir, you have a new sub from me.
Another good video! Much appreciated, very well explained. What I have been looking for, being a newbie, - and there is an overwhelming amount of information out there ( too much) is a series of LiFePO4 videos, well linked together.. that answer the question - OK, I got my batteries finally, now what? What is a step by step procedure for
Connecting in series vs Parallel ( thank you!)
How to charge your batteries ( thank you again for your vid on that)
How to balance your batteries ( thanks!)
How to measure their capacity
How to discharge them
How to hook up a larger BMS w details
Not sure what else, or in what order...
Just my 2 cents
Good questions all around. I'll be making more videos that will hopefully address some of your other questions.
Thanks for the video, especially for making it understandable. I was thinking i wanted two separate banks for the scenario you covered at the end, if something happens with one bms your screwed, with two you can still have power with one bank. My question is, what size bms to get? I see the daly being used with lifepo4 banks and they seem durable, Will prowses milk crate build is about what im thinking of doing. I did see another van lifer video where he added some heating pads and sensors since he was in the cold weather, and being from michigan i may watch that build again to add the heat pads. The cold build used a 80 watt bms and Will used a 250. It seems like a big difference, and neither used two banks in parallel which i will be.
I think it was about 15 mins in on your video where you covered it, but didn't mention the bms you would use and how you would run them together. Any chance you could give me your recommendation on the size bms, I'll be running a mini deep freezer and a 5,000 btu ac, with just a few lights in a cargo trailer with 4 200w solar panels on the roof. I was impressed with the max output of the 250 Will used so seeing im going to run an ac, should i go to the larger bms to be better safe than sorry? My apologies if this is rambling lol, but i appreciate any recommendations on sizing and how to configure them together. Thanks!
This is a good question. Always go for a big BMS. Most of the cheaper ones say they are rated for a certain capacity, but in actuality really can only do like 80% of that, so oversize them. I've been using Daly 250 amp smart BMS. It wasn't easy to get it working properly, but it is working now. Otherwise there is overkill BMS as well. But everyone is out of supply right now unfortunately.
I was able to acquire a 96kw Absolyte GX (2 volt) series battery bank. Have you ever worked on something like that? I need to wire 24 cells into 48 volt configuration for a 48 volt off grid system. I'd appreciate any assistance if you had some time to assist. I'm also wondering if it is possible to utilize a BMS on this size to constantly monitor the entire bank. Thank you so much for your videos! I have subscribed - looking forward to watching your old and new videos!!
Hi, the Daly BMS link is for a BMS on Amazon that is for the 18650 batteries. Will that work for the large cells you are using? Sorry for the newbie question and thank you in advance for your response.
BMSs don't care if the batteries are 18650 (cylindrical) or the big ones I am using (prismatic). As long as you can correctly wire them to the battery, they will work fine. BMS care about the chemistry of the cells, not the shape of cells. Good luck!
@@TheWilltoBuild Hi and thank you so much for the response. I noticed the one you had a link to was so much cheaper than other ones I have looked at that I was hoping it would work. I am looking to build a 4s 12v 200ah battery so .. pretty basic and was hoping! Thank you!
Ok I have an RV with one 100w solar panel one charge controller and two agm 51ah 12v batteries and one 12 deep cycle ah unknown lead acid battery what would be the most efficient way to install these so they charge and supply 12v to my system? Please and thank you
My build 4s 2p sir and the battery next to negative main is the one who charge full 1st then next one beside the main positive is the 2nd to charge full and the main negative and main positive remain to 3.37v.
My active blancer is 4s 5a and 60a discharge/30a charge current bms. My problem is i can't balance them when charging on solar panel before i assemble them i do top balancing 1st. Hope you can help me or i will just follow your advice which is 2 bms
Hi! Would You do the same with a 48V battery with 32 LiFePo cells or 16S 2P? Thx.
I plan to do a van conversion build. I have been looking everywhere on youtube for this sort of video. I want to have 2 DIY batteries made up of 280ah cells from aliexpress, and these batteries i plan on connecting in parallel and hope to run 12volt appliances from it and also a 2000watt inverter. I want to have a 250amp rated Daly BMS on both of the separate DIY batteries. I need to do more research on solar charge controllers and DC to DC charging and all that stuff but... Can you see any holes in the rough idea I have? would appreciate your feedback
Honestly it sounds good to me. Doing two 12v batteries, both with a separate BMS, sounds like a good idea. You could also just do a 24v system and use a converter to run 12v appliances, but that may be more trouble than it is worth.
@@TheWilltoBuild thanks, how long have your 12v DIY battery systems lasted ? Are they holding up well ? Also have you had any experience with the 310ah ones... I trying to figure out if it is just fake advertisement from aliexpress
Hi I'm new to the lithium game and I am into car audio and I have just purchased 8 3.2 90ah cells like in the video and just wanted to see if you could make a diagram of how to wire them in 12v 180ah thanks and like your videos
Great Video..
Could u please clarify your note, why not main negative? Is the black and white reversed? I would have thought white was positive.
Could you please show a 2 bms setup not work all cells in one long line rather than in a square format.
Thanks
Hi, does this Bms or batteries can communicate with the inverter by internet com port?
This basic BMS does not. No communication at all - which is true for most basic BMSs. More sophisticated BMS do have communication options, most often by bluetooth.
@@TheWilltoBuild Thanks your videos are very Educational!!
Hello, how can I connect two bms to an inverter if i decide to do 16s2p. Thank you!
This is possible and will work fine. I have heard of someBMS makers tells people to not do this, but it is really unclear why this should be an issue. If you do two separate 16s batteries, give them each their own BMS, and then put them in parallel, it shouldn't have an issue unless the specific BMS is weird (so maybe check with the maker?). After all, many off the shelf batteries have a BMS (like battleborn) and you can wire those in parallel no problem.
@@TheWilltoBuild so I too have a16s bank x3 each bank is 48v100ah (so that is 48 batteries at 3.5v 100ah) i have a 16s killwat bms. My ? Is if i use the 16s bms can i still wire my batteries in a 12vx4 =48v or do i need to wire all 16s to = 48v and keep the 100ah for each of the three banks. I would like to at least go from 300ah to 600ah. Any help is greatly appreciated thank you.
Your videos are great !
Hi great posts best I've seen. I'm a newbe
Interested in building 4x4sp (3.2v 105ah) to create 48v.
I assume l can repeat your 8 cell example with 4 bms
Have a question. If 2-300amp BMS being paralleled, does it add up to 600amp max current draw or still the same at 300amp?
Can u tell / show how can I make a 48 v battery but with like 600 ah or more? I’m gonna buy 16 of these and I need 48 bt I also need higher ah because 280 is not enough
If you run 2x 100amp max discharge bms on the batteries for your preferred way of setting them up are you still capped at 100amps discharge or does it become 200amp discharge
What happened if is 12v 10amp or can you mix the amps eg; 12v 20, 12v 6amp or 12v 70amp !!
Congrats very well explained. My question is can you use the same process to wire Lead Acid batteries in series and parallels and at the end close the loop before connecting the Negative and Positive wires to the Inverter or leave it open witch one is better?
Thanks
You can wire lead-acid batteries the same - in terms of the basic wiring. I don't quite follow what you mean in terms of "close the loop". You do want to ever directly connect the positive and negative wires. That is a short circuit which can very quickly hurt you and the batteries.
@@TheWilltoBuild Thanks very much.👍
Hey, great video and Thank you for putting it out there. New to batteries and electrical systems but i'm learning a bunch. Had a quick question. Can we use the DC power supply as our main charger to charge up lifepo4 cells batteries or are they only use to top or low balance the batteries. I don't want to buy another charger if it's not necessary. thanks for your time!!
You can definitely use your bench power supply as your primary charger, it just might be kind of slow. Also, most cheap bench power supplies only go to 30v, so won't be high enough for 48v systems. But...I have used two bench power supplies in series to charge a 48v battery.
@@TheWilltoBuild Okay, Thanks! I have a 12v system with a 200ah battery. if it's charging at 10ah max, it would take 10 hours to charge up 100ah, correct? That's what the charger is capable off, right. Just wanted so confirmation/clarification. thanks again for your time and response!
@@stevensam8834 Yep - in theory you could charge the whole thing in 20 hours - but the rate of charging will slow dramatically when it gets close to fully charged so it will take longer than 20 hours (more like 30).
Good explanation and a cogent argument made. From an efficiency standpoint, a 24v, 8S configuration, with the proper BMS and 24v inverter, will deliver more power, correct?
Functionally, 8 cells can deliver the same power whether they are 4s2p or 8s. The 24v system has higher voltage, but the 4s2p can push more amps. That said 24v is still better in my opinion. Cells prefer to be in series, and 24v systems will need smaller wires and will be more efficient with an inverter.
@@TheWilltoBuild - I was basically referring to the efficiency ratings for the inverters. 48v is better than 24v, which is better than 12v. If the use-case is off-grid or emergency backup, the 24v, 8S configuration, paired with an appropriate inverter, will deliver more power with less conversion loss.
i watched this video and have a couple of question: 1) can you show or explain once i have connected the two sets of lifepo4 ( mine 3.2V, 200amh) batteries in series then connect these sets in parallel how are the BMS connected together to go to 12v fuse panel and charger. 2) Can you suggest what size BMS(2) i should use, would (2) 4s 12v 100a be ok to use?
Hello! I need some help with wireing my first lion battery pack. Ill have 6 4s lion batterys in parrallel, so i get 24 volts and 90000 mah. Because 3400mah*24 lion batterys is about 90000, or isnt it? I dont know, thats why i need help. Also, how do i wire them up, do i put the 4 cells in parralell in series with the next one?
Hey, I'm having a little trouble following your question. I think your amperage calculation is correct, you have a total of about 90 amps, but it is not the correct way to think about the batteries. What are you trying to do? Create a 24v battery? Do you know what type of cells you have? Are they lion or lifepo4?
@@TheWilltoBuild Aha, ok, i understand. I wrote really crappy english, i was very sleepy. I want to make a 24V lion battery for my diy bluetooth speaker. It needs to be at least 90Ah to last 9 hours. Its a big ass speaker! I need to wire 4 18650 batteries in parralell, and then use 6 of those to get a total of 24 volts. The only thing is that i do not know how to wire them up. How do i wire the 6 cells in series to get 24 volts?
Best regards, Linus.
Im new to the idea of lithium for my car audio endeavors. But does anyone know if i could get these for my truck and use them as a battery bank my max amperage pull would be about 800amps and ive got a 280amp alternator and gonna get 2 500amp switches for them. would i also need to get some sort of charge controller cause i remember charging is a big thing to try and make these things last.or should i just forget about it and get a couple deep cycle XS batteries.
You talk to fast 💨 no more coffee ☕️ 🤣
Good videos man
I made my 4s battery last night, and when I hooked up to the charger, I got sparks. All of my previous connections seemed good, but then I couldn’t charge the battery. Any idea what I may have done wrong?
Hmm, there prolly should not be sparks. Are you 100% sure the battery is wired up correctly? Also, did you attach the right leads from the charger to the right places on the batter (positive with positive, negative with negative)?
IS there any simulator for battery configurations?
thansk sir for explaining
please I have question is it healthy if I connect 4 sales parallel and connect themes on seris and following the rest on seris like I have 50 CELLS ON seris and 4 parallel can I link it on seris to each other the 4 cells parallel withe the 50 cells on seris
I'm sorry I don't think I understand your question.
well explained
I am having so much trouble finding those studs can you help me out on where or who to order from?
Sure.
Set Screws, item number 8740:
www.boltdepot.com/Metric_set_screws_Allen_Cup_point_Stainless_steel_18-8_(A-2)_6mm_x_1.0mm.aspx?Selected=8740
Serrated Nuts, item number 12009:
www.boltdepot.com/Metric_flange_nuts_serrated_Stainless_steel_18-8_(A-2).aspx?Selected=12009
@@TheWilltoBuild thank you so much!
Nicely explained.
I am wondering if I can connect a 12volt 200ah prismatic cell battery in series with 2 12 volt 100ah lifepo batteries in parallel to get 24v 200ah ? so there are 3 batteries total. 2 identical batteries in parallel for a 12v 200ah, with 1, 12v 200 ah. I understand its a less than ideal to put unlike batteries together but can it be done? I tried to do it but got a huge spark attaching the 2 parallel ones to the 12v prismatic. negative to positive and positive to negative. any suggestions ?.
Thanks for the video. What is the maximum current draw you would be comfortable with using those busbars?
Really good question. I'm not sure actually. I think they should be good for 50 amps at least, but I expect much more. But I'm not an expert in this will have to do more research. Great question!
thanks mane
Anyone know a fast resource for busbars for these cells?
That's a great question. I made my own and it was not fun, but I don't know an easy alternative.
When you connect 2 4s batteries together is it best to draw power from the bank by connecting to a negative stud on one battery and a positive stud on the other battery?
You mean together in parallel? Generally speaking both negatives should do to a bus bar and then both positives should go to a separate bus bar - and then you wire your system off of the bus bars.
@@TheWilltoBuild Sorry I wasn't clear. Yes in parallel. So you advise using busbars for even just a 2 battery bank? I see the advantage for a 3 or more batteries in parallel because it will facilitate an equal draw from each battery, but I am not so sure its worth the expense for cables and stud busbars for only 2 batteries. Any comment on that?
@@michaeldoherty2289 You just want to make sure you are drawing from each battery equally. You could potentially just improvise something, perhaps connecting a wire to each positive terminal (for instance) and then connecting that those two together at a third wire that serves as the total battery positive. All you would need for that is some wire, some crimps and a stud with a washer to tie them all together. If you go to your local hardware store of HD or Lowes and go to the electrical section, you'll see alot of stuff that can allow you to pretty cheaply connect three wires together.
@@michaeldoherty2289 You just want to make sure you are drawing from each battery equally. You could potentially just improvise something, perhaps connecting a wire to each positive terminal (for instance) and then connecting that those two together at a third wire that serves as the total battery positive. All you would need for that is some wire, some crimps and a stud with a washer to tie them all together. If you go to your local hardware store of HD or Lowes and go to the electrical section, you'll see alot of stuff that can allow you to pretty cheaply connect three wires together.
@@TheWilltoBuild OK. To follow up on this further I have one more question. Say I have 2 separate 12v battery packs just like the 2 at the end of your video. If I install a 4s BMS on each 12v battery. Then to parallel them I simply connect the 2 main 12v positives together with 2 equal cables going to a single post terminal. This will become the main positive battery terminal. Then connect the equal length P- leads from each of the 2 BMS's on a single post terminal which then become the main battery negative. This all happens inside my battery box (which contains both 12v packs). This way I do not have to connect the 2 12v packs together with solid busbars (the ones you said you didn't have long enough busbars to do that in the video). It totally resolves the question of which terminals become the main terminals when the 2 12v packs are connected with 2 solid busbars. It also assures that each of the now paralleled 12v batteries (or really all 8 cells) will be equally drawn upon during use. Is that clear and is that correct?.
I have a 4 battery lifepo4 24v battery bank with 12v batteries in series parallel connection . Problem is the 2 batteries that is connected to the inverter get 15,2v charge while the 2 other batteries in the series connection that is not directly connected to the inverter is normal 13,3v, total voltage is 28,5 for both battery banks. I have a battery balancer but it only balances the voltage of the 2 banks, not the 2 batteries that get way to high voltage charging.
It seems to me after what I have read about electrical engineering that to not get over voltage on the batteries that is directly connected to the inverter you have to have exactly the same resistance, meaning equally long vires to all the battery connections... But I have not see anyone ever doing series parallel connection that way. Everyone connect it like I have done with charging and inverter directly connected to 2 of the batteries in the series parallel battery bank and the 2 last batteries connected with longer wires.
Gute Lifepo4 top 👍😉
If I accidentally put the bus bars on wrong for a few seconds when I first got the batteries to “short” then. Did I permanently damage them to the point that I rendered them useless?
Almost certainly not. They are probably fine. Check the voltages on them and if the cells seem ok, you are probably fine to proceed.
Hello, Please I have this INVERTER Growatt 5KW 48V 220V Solar Hybrid Inverter SPF SPF 5000TL HVM-WPV-P Max PV Input Voltage 450V MPPT 100A Solar Charger Can Par . Please can you show me what type of battery I will need to run this?
What happens 8f you have terminal 1 with positive and a neggative leads aNd terminal number 2 are the same both coming out of my mobility scooter I was fine till I realized I had two two of the Same terminals
I ordered the same cells you have. 16 cells and I want to connect them into one 24v battery. What do you think it's the best way? I'm soooo confused!
It's definitely confusing at first. For a 24v setup, you can make two separate batteries, each made up of 8 cells, and then put them in parallel.
@@TheWilltoBuild
Ok thanks I definitely can do that. I also have a 16 cell bms, can I get away with 1 BMS or do i need 2 of them?
OK I like the way you did it. I have 1 question I have two BMS but one is 4s 12v 100A and the other is 4s 12v 120A both are made by Daly. Can I still use those two even tho they are different in Amps?? Thank you.:)
Yep, that should be fine.
Good evening LtB... I have an unrelated question that you may wish to answer..? I have two solar generators and would like to power both at the same time using one 180 watt solar panel (instead of a separate for each).. Realizing that the sogens cannot be connected together in any way, my solution would be to provide the necessary branch mc4's for each sogen and isolate each branch with an inline mc4 fuse which already has the diode built in to prevent vdc back charging. Your thoughts..??
I really can't say I've ever encountered anything like this, but my feeling is that feeding two separate solar charge controllers with one panel is a bad idea. I would suggest just adding another panel and having them be completely separate.
@@TheWilltoBuild "feeding two separate solar charge controllers with one panel is a bad idea".... Why...??? If each pos leg has a blocking diode in the inline fuse to prevent back feeding to each other across the mc4 branch (which acts as a voltage divider) and one sogen from charging another...? I already know that I can connect one to the panel and the other to the ac inverter...
Well explained Sir that was really perfect man 👍 keep up the awesome content and I think you people know each other
@Solar power channel with Chris
Glad you like it.
One good tip that I haven't seen others do is take a strip of masking tape and paint (spray gloss enamel, etc.) it red and let it dry. Then cut it into little squares and affix a piece to the top of the cell next to each of the positive terminals. It elimates all confusion as you are rearranging or working with the batteries. Never second guess which is the positive terminal. I also mark each cell's number on the red tape, (1,2,3,4,...) For the cells in order. Also I number the balance leads with tape as well. I love your long studs, are they Stainless? Which length did you go with?
Great advice. There really is no harm in being extra careful and it would be very easy to make a mistake. I get the set screws (studs) at the bolt depot, and in this case the are 40mm. In hindsight I probably could have gone a bit shorter.
hi i build my first electric trike using fiat 500e lithium battery packs each pack is 24v i use 8 packs in series for 200v but i have 2 24v packs left over i would like to parallel these two packs and use them as a range extender to the end of my 200v pack is this possible. my pack of 200v all get charged and balanced individually so one pack of 24v to one charger . will this work for range extender.
It sounds like it would work. But are you using a charger? and what is the input to that charger?
How do you hook up the 2 bms. I'm building a 12 volt with 2 bms and 8 cells in one case. Trying to wire it so only one positive and negative.
I have 2 separate 4s cells batteries . With the b- going to the main negative on the first cell. SO do I wire from one c- to the other c- and have the main negative come off of that?
hey, I've answered this same question for you on the other video.
Can you charge your cells on your alternator? Thanks
No.
If I have 4 50ah 3.2v cells how many ah do I have
Hello. What's your recommended Lifepo4 charge parameter ? Float & bulk voltage. Thanks
Great question - I'll be doing a video on that later this week!
Can I hook the two 4S batteries up in parallel with separate BMS and charge/discharge them with a single source safely & efficiently? Or do I need some sort of third system to monitor the combined batteries in parallel? What happens if I only use one half of the system individually (I take it with me as a portable power source) and the 4S batteries are then at different charges? I need to charge them both to max again before connecting them in parallel, right?
You can definitely put two 4s batteries in parallel with one another, this is very normal and shouldn't be an issue as long as they are at the same voltage. If you put them in parallel when they are different voltages, it could be a big problem. If the difference in voltages is large, LOTS of power could flow from one battery to another. Try and match the voltages between the batteries very closely. They don't have to be identical, but pretty close (I would say .25 volts or less).
Great, thanks@@TheWilltoBuild ! What about using one battery more than the other over a longer duration? If you link them, you would potentially bottle neck the less used one since the more frequently cycled one would hold less wh, right? So I should try to cycle them equally over their lifetime?
@@nikzel Good point. Yes, definitely try to use them an equal amount.
@@TheWilltoBuild Hi, like to follow up on this one. Cause, I have 8x 105AH EVE's on the go. 12V system is mandatory and I consider 2 individual batterypacks to be comfy. I'd like to understand what's going to happen exactly, if I stress them separately and connect them to 210AH 12V intermediate ? Let's assume to use generous connectors as well as both have each a 60-80A BMS. Won't the BMS'es amoung themselves manage/restrict to settle "the situation" ? Elsewise any suggestion how to solve this, may with ?relay? Setup should be for a camper van: charge with cars alternator & solar on the roof Battery1 and go fishing with Battery2 to run a boat engine.
@everyone what is the most effective setup I can build with 12 of these cells?
probably 4s3p? Three 12v batteries then wired in parallel? I would say get four more and do a 48v system if you can.
@@TheWilltoBuild exactly what i want to do.... following your example above... but doubling it... do i then just continue the main + and main - horizontally .?
So you didn’t show how to wire the last one with the 2 bms’s and which terminals to connect to which post to the inverter.
I don't have two BMSs to show unfortunately, but you would just wire the positives together, and then also wire the P- from each BMS together. Then, to connect to the inverter, just connect the inverter positive to the positive of both batteries, and the negative from the inverter to the two connected P- from the inverters.
I love it
You do really explain well!!! Kudo's!!!
I recommend you rather "voice-over" your videos from a script (not ad-lib) to avoid small errata ... (e.g. you mention 580Ah in stead of 560Ah.);
alternatively get voice recognition software and read from the translated script.
As an engineer, I completely agree with assembling 2 x 12.8V batteries each with their own 4S BMS in stead of 1 x 25.6V battery with 1 x 8S BMS !!!
Thanks for the pointers, I appreciate it.
I have 8 cells soon arriving for 12v setup,and an 8s bms(daly).will it still work for me setup as 4s2p(hopefully have that right)
For a 12v setup I believe you need a 4s BMS. 8s would be for a 24v setup.
Yep, he's right. You can't use an 8s for 4s2p. You can either do one 4s2p combined battery with one 4s BMS, or two 4s batteries with separate BMS and wire them in parallel. But if you can run a 24v 8s system that is best and do that!
hi question
in the the 2x 12v baterij setup is it possible to use 2 diffrent amperage
like 1 batery is 12v280AH an the other 1 is 12v100AH
Definitely not. You can not mix batteries with different capacities.
@@toastiesvanbuild4644 I think it is bad idea to do it for any extended period of time. If they are genuinely in parallel, the larger battery will constantly be charging the smaller battery, so for every charge and discharge cycle, you are going to work the small battery twice. Generally speaking the battery community this is seen as not advisable.
Can I go up to 16S -4P?
Can I ask where did you get your watch, I need one like that so I don’t have to wear glasses
Yeah 2 separate battery bank is much better, did mine parallel to (+) & (-) buss bar that connect to my inverter
Hi can i use just one 8 port bms this system ? Many thanks
Sorry, don't quite follow your question. 8 port bms would be for an 8s battery. If you are using lifepo cells, then that is a 24v battery.
@@TheWilltoBuild hi im try to use 12 volt i must use 2 bms rigt ? Many thanks
16s3p? is that a thing
you could definitely do it, although generally speaking I haven't really seen it.
Can you do a 8s2p 16 cells 24v
Yes, you totally can. I would recommend doing two separate 8s batteries and putting them in parallel.
Really need to know why you said you would not recommend
Two different brand batteries in the same bank..or why mixing
Energizer and Duracell’s is a big
No no so to speak?
Just because different brands are likely to have different capacities and different behaviors, in particular internal resistance (IR). If the internal resistance of the cells is different, then some cells will charge and discharge faster than others. That extra work will age the cells faster, and then they will have different capacities - which will also cause them to charge and discharge faster and wear them out even more! This is actually a good video topic.
@@TheWilltoBuild , I don’t believe there is any hard data that supports this preposed you tube theory, I have heard other videos repeat this information over and over in explanation but lacking data to support this. That’s exactly why I used the two different batteries as a example. IR is easily measured and would more than likely be so minuscule that it would not be notable even in 1000s of cycles. However the proof is always in the pudding. It would
Be a great experiment…
@@TheWilltoBuild, Lol Thanks for the videos super appreciate the time and effort..😊
confusing stuff.. So 8s2p is 8 cell's, 2 pair's of 4 cell's ?
No that would be 16 cells. 8 in series with 2 in parallel per series connection.
Got an 8s4p with these cells, 25.6 volt and 1120 Ah :D Might change to 4 batteries if I have a problem.
@thewilltobuild How did you calculate your Ah? and what are the advantages etc? What do you need for the 8s4p?
@@Mellosucc3ss 32 cells 8s 24v 4 parallel x280ah =1120ah 500amp BMS, advantage is that with large loads one 24v battery failing could cause the other exceed their rating. Each block of 4 self balances meaning you're less likely to under/over volt one cell. Its also the way Tesla build their packs but they then series connect those packs 😮
@@TheGalifrey did you say 32 3.2v cells? 🥲 I only have 12. Would that work for a 8s4p?
@@Mellosucc3ss no, sorry
If I had 32 cells I would do 16s2p - but 8s4p works. Generally speaking though putting cells in series is better than putting them in parallel.
If u would of properly mentioned the voltage & amp hours and how they differ in each bus bar configuration would of been a lil more helpful.
Good information but sacrificing clarity for speed remember beginners 🤨. Thanks.?
It's very good. I need an A-level battery to contact you. the price is very good~
lots of oks in there get a life