How the Seplos BMS handles balancing. (it actually sucks🤦‍♂️)

[@kooscombrinck3753]

Thanx Andy! I was in discussion with a Seplos agent the last week and they think their stuff is great! Your testing put the proof next to the pudding. I think JK is tops so far out of your your testing, I planning my own Solar DIY project for our home here in Sunny Hot Free State in SA. I have gain a lot of info from your channel and WILL abuse it to my my gain!👽👽👽👽👽

[@USA-GreedyMenOfNoIntegrity]

Try a JK 200 amp for the 16S. You'll love them.

[@OffGridGarageAustralia]

So far, the JK seems to be the best option for our batteries.

[@FutureSystem738]

@@OffGridGarageAustralia I second that Andy, my 16s - (24s) JK BMS is working perfectly- I love the functionality and ability to easily set whatever you like on ALL parameters. And even though my other 4s - (8s) BMS for my caravan 12v battery was faulty, they immediately acknowledged the issue, refunded my return postage and quickly sent a new one once they received my faulty one. I really love the JK BMS, and can’t really fault their service at all. These other BMS’s with very low balance currents just don’t have the capacity to balance slightly imbalanced cells.

[@kooscombrinck3753]

I plan to build a 16s 4p 320ah (65.5 Kah) rack to powering 2 x Growatt 5000ES inverters that should draw at worst 227 A on full 10Kw (44V) if needed, so I took the 250 A Jk bms, this will be recharged by 18 x 455w Mono panels trough the Growatt mppt. I will make videos as I progress ( not the off gritt standard) but I want to follow my own ideas and explore to see how lifep04 reacts to that sequence. I ordered a 4A 16s balancer for top balancing. Andy INSPIRED me and with all the loadshed 💩 we got in za and bbbee sabotage here "maak-ń-plan" is at the order of the day!

[@FutureSystem738]

@@kooscombrinck3753 Excellent. I feel that we will likely be seeing load-shedding in the evening peak even here in Australia this Summer, any time there is extreme hot weather OR almost any kind of equipment failure. Last summer we came extremely close to that when there was a catastrophic turbine explosion at one of our biggest power stations. With a battery, (still “under construction”), now I’m not concerned and there is no need to keep a generator fuelled up and ready to go.

[@JayDee25895]

Best all-around fun show on KZbin! Thank you, Andy & Congratulations.

[@evil17]

Good job, vid, data, thanks Andy, this is very helpful info. Seplos needs to pick up their act, I hope they are listening and responsive, but many previous comments have shown that they are not. The Battery Build is mostly really good and solid, it looks great, but their; Communication, Packaging, BackupSevice, Instructional Dialect, PC necessity, No B/T app, and Passive Balancing SUCK! I have 3 x Seplos 5Kw “Suntorque” batteries, 2 of these steadily decreased from new, and after a few months were down to only charging to 64%, Until I watched your recent series on Seplos gear and done some more research. I completely discharged each battery till the inverter shut down & then recharged them back to 94% & 96% respectively after the first time I did this. I bought these batteries because they were advertised as ‘Plug N Play’, no need for comms etc, but they really are not that simple. SEPLOS, do yourself & everyone a favour, listen to Andy and make the necessary changes, or you will lose the race. I would like to buy one of these kits for some 310A cells I have, but I would have to consider making some mods & adding an active balancer, which I dont believe I should have to do at this price point. Thanks for ur great vids & info

[@batterynerd8779]

Great Video! I have just upgraded my solar system with a 3000 Watt inverter from this Cnswipower brand. The same as you have but the 24 volt version. It‘s amazing! The price is right too! Thanks so much for the information about it!

[@DanBurgaud]

14:24 "... BMSes with 40, 50, 80ma balance current ... " And then installed on 100AH, 200AH, 300AH battery of all that... 100ma balancing would take 10hours just to balance out 1AH of capacity deviation...

[@OffGridGarageAustralia]

Yeah, as we have seen, it does not really balance anything at a constant voltage.

[@DanBurgaud]

@@OffGridGarageAustralia I can already hear diysolarforum gurus shouting: "Active balancers are for poorly designed batteries."

[@OffGridGarageAustralia]

@@DanBurgaud Or for everyone who bought 'genuine A-Grade' batteries like I did 😂😂

[@sebydocky5080]

@@OffGridGarageAustralia I am jaleous :( :(

[@AintBigAintClever]

I've got two HA02 balancers on my current lead-acid setup. Once my LFPs arrive I'll be putting them across pairs of LFPs so at least I'll have a semi-active balance with the Seplos only having to deal with balancing the midpoint between each pair.

[@nunyabusiness9760]

This will sound like throwing good money after bad, but the "NEEEEYYY" Gen4 sounds like a good fit for this BMS, it will address the balance current shortcomings and give BT interface to monitor cells status and allow tweaking of balance parameters. I imagine that once the safety thresholds in the BMS are set (via PC) there would be little need to mess with them. The Neey may/should be able to tame the runaway cells that trip the warnings and protection messages....

[@PhilippeCJR]

i am planning this 15kwh seplos box, and then put eve 280 of 304 cells in it....but, with a neey 4a balancer also inside. would be good solution i guess :)

[@jasonmann5019]

Excellent information. Thank you for sharing. I am also interested in Andy2's take on this in another video.😀. Best wishes Jason from Melbourne Victoria.

[@OffGridGarageAustralia]

Coming soon!

[@jasonmann5019]

@@OffGridGarageAustralia Looking forward to it. 🌞

[@FutureSystem738]

Thanks again as always Andy. 👍 (BTW I’m pleased to say I have received my replacement JK 4s-8s BMS for the caravan - haven’t connected yet but it should be good I’m assuming.) Edit: my replacement 12v BMS is all good, has been mostly tested though not yet permanently fitted in my caravan.

[@czarnuszewiczmatt]

Hey Andy, the purpose of the copper washers are for crush purposes, this will help to ensure a proper contact surface, this is why the torque amount is so high. please look up some videos with help on annealing copper washers (they may of already been heat treated) . I am a AU/Bris. sparky with solar on/off grid design/installer, hope this info helps.

[@team13thirteen]

Daly Balancing 2.0 can't wait for the video :D

[@OffGridGarageAustralia]

Coming up next. Already editing...

[@Woodyjims-shack]

I bpught a Seplos 200amp bms which is ready to deploy on my recently tested 16s 280amp Eve cells. It does seem slow when compared to the JK bms etc. I'm keen to see how they operate together. The settings look daunting in the software. I'm sure all these options may be useful to some but for me it adds to the complexity of what is a relatively simple task🤔

[@OffGridGarageAustralia]

I'm currently working on the communication side of things to make this all work. Total f*** nightmare!

[@ondrav5058]

Andy, 3,4V is start voltage for balancing, next look at point 62 and 63 (open diff and close diff). Look at the value of SMD resistor on BMS, from resistance and voltage is possible calculate balancing current (when you balance on 3,45V current is smaller than on 3,55V). When you dont use can bus for inverter, switch off intermitend power supply function, this function is made for this I Think.

[@OffGridGarageAustralia]

That is correct, hence I charged all the way to 3.65V to see the balancer in action... 🤷‍♂️ Not sure about this power supply function, nothing in the manual.

[@patrickmartin4482]

@@OffGridGarageAustralia there is a dedicated PDF that describes all settings: Intermittent power supply function When the SOC reaches 100%, if the SOC exceeds the setting value (which is 96%), the charging MOSFET will be cut off. And the battery can not be charged.

[@natesdiysolar]

This is exactly what I'm experiencing right now. Very frustrating. FYI there is a BT app.. I had mine on the charger with that intermittent charging for 20hrs and no change .. ..

[@HawK4all]

Hey Andy, thank you very much for your Videos ! You've transfered ALOT of knowledge to me! Remember when i asked if you could try to connect the SEPLOS to the Multiplus? It should be able to do so according to SEPLOS. Why? Well maybe that could spare the smart shunt ;)

[@excillisbank2611]

☺ merci pour ce test et toutes ces explications 👍

[@warrenburchard8661]

Hi Andy hope you doing well it's Warren from pacificblu solar I must say your channel is the best solar channel on KZbin I have learned a lot from you keep it up. What do you think of the EVO 5.7 kwh batteries.

[@colinturner7363]

hi andy just a quick question if i could did you have a video on seplos where you built the mason cells and bms all setup then you used the lifepo charger (blue 3.6v) on each cell between each cells terminals (+ -) so pos neg cell 1 pos neg cell 2 etc and bought them up to a voltage of say 3.6 v all while still connected to your inverter system

[@rogerlittlejohn475]

I have had my Seplos bus for months, and find that it does not balance. I have three batteries that run higher than all the others and two that run lower.

[@FutureSystem738]

And this is EXACTLY what Andy is getting at. Unless you have absolutely perfectly matched cells, balance current of only 100mA is close to useless.

[@martdaymo]

Did I glimpse a new active balancer in the background red in colour?🤔

[@OffGridGarageAustralia]

Yes, I bought all of the Daly active balancers. It will be in the next video. Big comparison...

[@ToThePointGarfield]

Still awaiting the cells i ordered on ali from OYE in CHN. That takes a long time pffffff. Bought few weeks ago a JK BMS as per your guidance. The 8s 200A that was cheaper on banggood. Thought it would do 4s but alas. Lucky you tested a JK BMS on a lower voltage using a DC power up converter. That arrived this morning and works WAAAAW. No matter what input the output stays 24V. Just them damn cells now and i can build my own 12v 400A battery for the mobile home. Anyway you don't have a accent ( ex-German ? ) LMAO Many many many tnx for your info and guidance Andy WAAAAAAAAAW

[@dubusonrenovationszarius]

Hi Andy can I mount a inverter on it side, not enough space to connect vertical. Regards zarius

[@bilalbhatti7549]

It'll balance off after it hits 3.56v and then it balances and trickle down to 98.5% .. and restricted charge starts again with 7-3 amps.. and then it auto charges with 300 waats. And stops at55-5v to 54v brings down to 53.5v while balancing .. charging with, 58.4v.. so that it uses it's resistance with it and gives around ,55.5v at load stage

[@Blueworld950]

Hi Andy,my cells are not balanced,can you suggest a balancer for top balancing I have 8 cells of 3.3v with 200Ah

[@hendersonsobers396]

Hi Andy, really enjoy your videos. I agree with you totally about finding out what happens if one battery has an issue, does the Seplos system shutdown only the battery with the issue or does it shutdown all batteries. I had a few email exchanges with Seplos (they are really great at responding) and they told me that all batteries would shutdown if there's an issue with 1. I'm not sure if that makes sense considering it's multiple BMS boards each with their own FETs, shunts, etc, but definitely looking forward to you testing this out to see what happens. Truth is, after seeing the results of your Seplos reviews I am beginning to place less value on the whole communication thing and wondering if building my system with independent JKs wouldn't be the better option. I do like that with Seplos, once I make a change it replicates to all the BMS boards, but on the other hand, I shouldn't be making many (if any) changes once my system is built and functioning as expected.

[@USA-GreedyMenOfNoIntegrity]

I have 10 batteries. None communicate with each other or with the inverters. I don't want all my batteries shutting down if one fails. My Sol Ark 12 k's would not like it.

[@OffGridGarageAustralia]

If this is the case and all batteries shut down, it would be a terrible design. If you have an off grid system, you would lose power all together. Mine is designed so only one battery shuts down and leaves all the others connected. I didn't know the settings are syncing. That's actually a good feature. But as you said, once set, there is no need for that. Yeah, I'm battling with the communication at the moment. It's f*** nightmare. I'm close to...

[@adibu06]

yup, that it what it does.If one cell charges quicker it will turn off all charging. This is what mine does with same BMS.. Probably I need to balance it manually.

[@OffGridGarageAustralia]

Yeah, do a full top balance and see if all cells stay that way. If they are well matched, the internal balancer of the BMS may be enough to handle the battery.

[@HawK4all]

Well and sorry i forgot is it possible to bottom balance those SEPLOS Systems? i heard that bottom balancing is a good alternative due to the cells balancing themselves to the value of the lowest cap cell.

[@repairman2be250]

150 - 160mA balancer to balance a ~280Ah cell - does not even tickle the cell! Seplos go back to the drawing board and produce a sensible device to do the job.

[@OffGridGarageAustralia]

Yeah, as we saw here even cells at 3.65V don't really get balanced. Even the QUCC with its 200mA did a better job with that.

[@repairman2be250]

@@OffGridGarageAustralia They could even do a separate PCB that plugs into the main PCB. Well, you never can get that non plus ultra device.

[@OffGridGarageAustralia]

@@repairman2be250 like a hat. An active balancer hat for the BMS. Great idea!

[@repairman2be250]

@@OffGridGarageAustralia I mean there is plenty of room in the Seplos housing to have the balancer fitted.

[@todamnbad]

I have almost 200mv difference on mine, alarms everywhere, trying to see how you got into the BMS settings page and of you made any changes to the BMS, thinking I might take all of the cells put amd do a top balance or use my neey to do it, still deciding

[@awesomusmaximus3766]

Great job bro The only way to keep the cells in perfect balance is for the balancer to know usable ah in each cell that unfortunately requires one shunt for each battery

[@Irilia_neko]

Will not be really expensive to add i think

[@CollinBaillie]

Each cell perhaps? Since this is 16 cells which make a single 48 volt battery. Battery literally means a group of cells.

[@geraldhenrickson7472]

I know no one who tries to balance current capacities. Its a voltage balance. Please elaborate on your reasoning.

[@CollinBaillie]

@@geraldhenrickson7472 I think he's referring to the fact that traditionally state of charge has been calculated by the voltage level of the cell. This worked because voltage vs state of charge was reasonably linear. With LiFePo4 cells the voltage level changes very little across most of the capacity, so you can't look at the voltage level of a cell and say that's 20% charged or 80% charged. The only real way is to count amps in/out and use the difference between total aH capacity and current "spent" aH as tracked. So A. Maximus is considering the idea of counting Ah to then decide if a cell is fully charged or not. Not really how cell balancers work, considering that voltage level is a critical consideration, at both ends of the charge curve. I guess State of Charge can be a confusing term sometimes. The true state of charge (as a percentage - ie 72% charged) would (for LiFePo4 cells) indeed be counted aH vs total aH. Cell balancing is based on cell voltage, as you're looking to protect the cell from over-voltage situations which would diminish the capacity quicker or even more catastrophically damage the cell, not balancing a state of charge. Of course this effects the SoC for each cell, but that's a side effect, not the target effect.

[@BackyardAussie]

going to order more lifepo4 cells.. who is best Qishou or Basen ??

[@PabloTBrave]

Have I missed a video how did you get to see the balancer it wouldn't connect before

[@OffGridGarageAustralia]

Ah, nah, this is the first Seplos battery I built. I jumped back to that one to test the balancing. Sorry, that was confusing. The other Seplos 280 DIY battery will be in one of the next videos.

[@lennieadi]

Hi Andy. Can the mason kit dispense with the seplos and install a JK? Is it worth the time and money? I wonder what other viewers think too?

[@garys-half-baked-offgrid-dream]

Andy Congratulations on the 40k well done mate "Kiss, Kiss" 🤣🤣🤣

[@OffGridGarageAustralia]

Hey, no kissing I said! 🤗

[@garys-half-baked-offgrid-dream]

@@OffGridGarageAustralia 🤪🤪🤪 Shine on dear boy!

[@electronpower2758]

Seplos is different for its ability to communicate with inverters. And it also powers on other same batteries in parallel using communication cable. This ability is rare and we will see if this outweights slow balancing and some quality issues Andy is discovering. Of course i want the Seplos to be good product as i have 3 of them, not connected yet. Go Andy go! I need to know if i should get at least 1 pcs of 4A Neeeeeey balancer for setup purposes.

[@USA-GreedyMenOfNoIntegrity]

It's unnecessary.

[@OffGridGarageAustralia]

I want this to be a good product as well. And it is, just not the balancer it seems. The communication part is totally overrated, in my opinion and not a reason to buy a Seplos BMS. We will get to this soon.

[@electronpower2758]

Maybe you are right. I'm interested in the total power loss generated by the MOSFETs. Some BMS has relay some MOSFETs. This would be interesting discussion.

[@OffGridGarageAustralia]

@@electronpower2758 I have both, BMS with FETs and relay. I guess the losses are roughly the same because the relay has a much higher self consumption when activated. FETs have higher resistance, so...

[@patrickmartin4482]

Exactly, there are not many that communicate with SMA which is widely used in Germany. I am adding neey balancer and disable seplos balancing

[@setalio708]

hi, Intermittend stops the Load at 100% SoC, turn the Funktion Off

[@OffGridGarageAustralia]

It already stopped before reaching 100%. The settings are annoying und unnecessary.

[@jcs1492]

Andy on seplos V2 BMS,do you recomend an additional active balancer ?

[@OffGridGarageAustralia]

That totally depends on how you charge your battery, how long they have time to absorb and balance and how much they drift at the top. I would always recommend NOT using an active balancer if not necessary.

[@danmc1313]

Worrying. Not sure what best to do when my Seplos arrives now. Retrofit a JK BMS maybe?

[@Fritsvrolijk]

Good-morning Pro i want 2 get myself a Fronius gen 24 8.0 do you think that a good thing 2 do /Regards from Holland

[@PhilippeCJR]

what beautiful garden and palm trees! can you make a video where you give a tour? :D :D

[@OffGridGarageAustralia]

About the garden???

[@PhilippeCJR]

@@OffGridGarageAustralia yes haha 😎👍 would be nice to see a bit more around the garage

[@milan2931]

Why this Seplos don´t have wifi or bluetooth module? 🙄

[@diysolaradventures7894]

I'm so upset no matter how much I try to charge my cells they keep going all the back down to 3.32v they never settle on any else but 3.32 even after charging way up to 3.4/3.5 ect when I walk back and take a look they all the back to where I started what am I doing wrong ??

[@OffGridGarageAustralia]

That's normal and called the rest voltage. Even charging them to 3.6V they will go down to 3.3-3.5V eventually if no load or charger is connected. They are still 100% full, don't worry.

[@diysolaradventures7894]

@@OffGridGarageAustralia ohh ok thank you soo much it's nice to know I'm doing it right I'm waiting on 8 more cells to get here this week

[@Ericcando81]

Habe ich schon mal in einem andern Video von dir geschrieben. Mach es wie ich. Nutze einfach ein Relais vom Smart Shunt oder deinem Laderegler (geht super bei Victron) und schalte damit einen Aktiven Balancer bei SOC über 90%. Läuft einfach perfekt. Ja, Das BMS ist nicht perfekt, aber ich finde es immer noch besser als unzählige unterschiedliche BMS, wo ich ständig die App wechseln muss. So hat man alles schon in einer Software und die Akkus kommunizieren auch noch miteinander.

[@OffGridGarageAustralia]

Ja, das ist eine feine Loesung. Hier ging es aber darum nochmals zu zeigen, was das verbaute BMS kann. Oder nicht kann.

[@FutureSystem738]

I agree with Andy- Seplos need to build a better balance system with a decent balance current, and the ability for the user to set all parameters just like the JK BMS. 150mA balance current on a 280Ah battery is not anywhere remotely near adequate. That’s about 0.00053% of the rated capacity, (150/280000) and will only work for absolutely perfectly matched AND previously top balanced cells. It’s a sad joke really. 😞

[@pepermintpilot1694]

Connect a meter between the individual ballance leads and the cells and set on current check!

[@inmyimage1081]

Andy can you add all your AC parts to your website. I’m getting ready to install my system soon and can’t find all the parts you are using. Right now you just have the panel box on your website, not the breakers and other parts. Thx

[@nannygrandpaandbertie1357]

Andy, keep up the great videos. What do you think about the Mason 280ah kit having no breaker. How would you link more than one battery? Would you have one battery connected directly to the inverter without a disconnect?

[@bilalbhatti7549]

It stops at 3.55v and shows 100% SOC.. and other lower cell is like 3.3 v.. 200-300 mv diff with my 100amps

[@MichaelAConnolly]

So as of this moment in time do you still think it’s worth considering over DIY like Battery 2.0

[@markwitkop7022]

I am not an expert. However, it seemed that your setting of 3.5v. Seemed to be right on spot.

[@solarandwindinsouthtexasda1473]

Good afternoon I have a little question for you I have four batteries they are 6P 16s what is the best bms you recommend my system is based on a 75kw lifemnpo4 module

[@OffGridGarageAustralia]

So, this is all one big battery with one BMS? I would consider splitting them up in 6 separate batteries with each having its own BMS. The problem with parallel battery cells is that you don't have control over single cells and cannot monitor them. It's a bit more money spend but if you have such a large battery, You already spend a sh!tload of cash, so 5 more BMS will be OK. I would recommend the JK-BMS which I have on my website: off-grid-garage.com/battery-management-systems-bms/

[@solarandwindinsouthtexasda1473]

@@OffGridGarageAustralia i have 4 battery 6p 16s sow if I split them in 6 I will need 24 bms

[@OffGridGarageAustralia]

@@solarandwindinsouthtexasda1473 Oha, now I understand. OK, yeah, not sure if I would do that either...

[@solarandwindinsouthtexasda1473]

@@OffGridGarageAustralia they're total of 380 modules of 60ah each

[@Oli83two]

Ich habe ganz genau die selben Probleme! Über 55.2V gehen die Zellen auseinander und das bms ist nicht in der Lage das auszugleichen! Ich werde mir auch einen aktiven balancer holen. Was hältst du vom daly balancer? Den könnte man programmieren, so dass er immer angeschlossen bleiben kann. Reichen 1A balancer current? Übrigens: die intermittent charger waiting Einstellung lässt sich abschalten! 😉 viele Grüße aus Deutschland

[@OffGridGarageAustralia]

I made a video about the Daly balancers. Not good. kzbin.info/www/bejne/rZiQfXRsgMZmjbs

[@uhjyuff2095]

I wish the JBD BMS had a choice for "charge balance and Static balance" instead it is "Charge balance OR Static Balance." I would say the Sepos BMS has JBD beat on that front but still has other warnings that are a nuisance.

[@OffGridGarageAustralia]

Yeah, so far only the QUCC BMS can do both when balancing is enabled. Except the JK which can do EVERYTHING 😉 I don't know if this is just a software limitation but I would say so as it would not make a difference if the BMS balances only while charging or also at any time when the start voltage is reached.

[@pepermintpilot1694]

As I have said I have built 1 of these and have a second on order. I don't understand if JK can do it on a smaller form factor why can't the Seplos BMS. The Seplos pcb board is huge in comparison to JK!!

[@OffGridGarageAustralia]

Yes, I don't understand this either. Definitely Bluetooth and active balancing missing with this BMS.

[@gopikrishnayogarajah]

@@OffGridGarageAustralia Size I think is because of the inrush current limiting circuit that enables stacking and perhaps mosfets needed due to positive side disconnect ?

[@milan2931]

So final result - Seplos BMS don't take?

[@OffGridGarageAustralia]

The BMS itself is brilliant, the balancing sucks though. It will be in one of the next videos... working on it right now.

[@GapRecordingsNamibia]

Hi Andy, I think the weird naming you are seeing on the BMS software is because of the chinglish to english conversion, The "Total Pressure????????" warning thing is that not warning of hurting the graphite rods? Remember your video the other day telling us how the batteries are damaged? I do not know, just thinking out loud as to what it potentially could mean... What is the status of the Seplos 280AH BMS comms problem? Thanks again for the video's..

[@USA-GreedyMenOfNoIntegrity]

It's no better than Junk Daly BMS at 150 mA. The old "Intermittent Power" bs, where it shuts off for 2 to 8 hours. I will never buy another Seplos. Three JK's just came in. Set them up and test them on a test battery, with a test load, in about 15 minutes ea. LCD 4.3" love it.

[@OffGridGarageAustralia]

Yep, I also think the Seplos BMS is totally overrated. Especially the comms and balance part of things. Not good.

[@edc1569]

Andy you are aware there are hundreds of thousands of energy storage systems shipped and running in peoples homes with passive balancers. If you've got a well matched pack it is not a problem. Just about every rack mount battery uses the same balancer technology.

[@USA-GreedyMenOfNoIntegrity]

I have 10 batteries totaling 134kWh. JK with the 2A balance are the only ones that will keep most of them in line all the way up to 57.6V.

[@OffGridGarageAustralia]

I think this is because all these thousands of people having these energy storage system out there are not doing any testing with them and charge that high. The Seplos BMS by default charges to 97%SOC only and then turns off charging, regardless what the balance status is. That is a terrible feature. We are testing here on the channel and do things differently to find out about such flaws like the Seplos BMS.

[@jmaus2k]

Its because they are designed as ups battery storage that charge from mains for days. None of these bms designers allow for intermittent solar/wind charging.

[@magnuseriksson5721]

Off-Grid Garage hello. i would like to now what did you pay fore the Seplos batteris , or dig you have them for free for testing them

[@OffGridGarageAustralia]

You need to contact them via Alibaba or their website to negotiate a price. The shipping can be expensive depending where you are, so I negotiated a price including shipping for both kits including the two boxes of batteries. I got your email as well with the same question. Thanks.

[@Dutch_off_grid_homesteading]

Heya, well that's diapointing this shut be 1 of the best bms's with a good balance properties what a bommer

[@ipstacks11]

A lot of these balancers were designed for bicycle batteries or similar. What Andy is showing us here is an “under powered” balancer isn’t ever going to get the job done with batteries that are higher voltages and higher capacity (by a large margin). These under powered balancers have multiple problems like only discharging / charging one cell at a time, not discharging / charging with enough capacity to make a meaningful difference and silly settings that with smaller capacity batteries might be okay, but at this scale all of this leads to an unacceptable underperformance that needs attention.

[@jaroslavchytil5732]

Hi Andy, its a shame that you probably got the wrong BMS version (and Seplos should act!), or i dont understand why you are having such problems. I have two battery packs (not seplos kit but just BMS) and dont have these issues, i can charge/discharge around 80A without any warning and all time cell deviation is around 8-15mV. Luckily you have your own battery sets with different bms which works for you like charm.

[@Josh-b3c]

I say play with those settings in there and see what they do switch one on and off at a time and see what changes maybe there's one that takes away that you have to discharge to whatever percent before you can recharge again thing that's especially terrible

[@USA-GreedyMenOfNoIntegrity]

Too many settings. Too little balance current for grade B cells!

[@OffGridGarageAustralia]

Very hard to do and play with these settings as some may have an effect while discharging other only while charging at a certain SOC. It's clear as mud...

[@MichealG]

Please please Andy, could please do it. It would be a great help for those who bought the seplos bms. And we may discover something interesting and beneficial.

[@OffGridGarageAustralia]

@@MichealG okay 👍

[@Black93gthatch84]

Hey Andy!!! Love your channel! Hey did you try to put an amp clamp to check for current on the balance Leads?

[@OffGridGarageAustralia]

The balance cables are too short for my clamp meter, so I couldn't do it.

[@Black93gthatch84]

@@OffGridGarageAustralia I'm sorry andy, a few minutes later I realized that you said that in the video I was too fast to jump to conclusions.

[@todamnbad]

So with what you have seen so far would you recommend anyone purchase a mason 135?

[@USA-GreedyMenOfNoIntegrity]

no

[@OffGridGarageAustralia]

yes

[@evil17]

@@OffGridGarageAustralia I take it that is a Yes, with Caveat’s.

[@todamnbad]

@@OffGridGarageAustralia my mason 135 has two cells that have what looks like a white vapor or frost under the vent cover, do you know if this is a sign of a vented cell? I have looked all over but can't find any example pictures of a cell that vented

[@USA-GreedyMenOfNoIntegrity]

Well it doesn't look like the current balancing light is on. What are your parameter settings?

[@igorybema]

Which light? The cells which are being balanced are visible in the windows app showing the cells flickering

[@OffGridGarageAustralia]

Yeah, which light?

[@rozarijorodin]

Andy... Is your battery 15S (54.75V)...? Because 16S is 58V...is it?

[@FutureSystem738]

No, Andy’s battery is 16s. The LAST thing you want to is charge to absolutely max voltage all the time. That will very quickly kill the cells.

[@nunyabusiness9760]

Because of the Seplos BMS's pathetically low balance current, the only way I could verify that the BMS was balancing my 280AH cells was to lay a finger across the balance resistors and feel which were warm ... The IR camera would have been better but couldn't get a good viewing angle.

[@USA-GreedyMenOfNoIntegrity]

oh, they are working. I measured them pulling 75 mA from two highest cells.

[@OffGridGarageAustralia]

The IR camera is a great idea👍

[@salarhadi2988]

Yes passive BMS it’s very slow, the BMS which have inductor or high frequency transformer type it will balancing very Fast . Thank you for your test.

[@CollinBaillie]

I can't help but think the intermittent charge toggle and the intermittent power warning are related.

[@USA-GreedyMenOfNoIntegrity]

try reading their user manual. You'll be just as confused when you get done reading. Too many options, parameters and many that don't make sense

[@CollinBaillie]

@@USA-GreedyMenOfNoIntegrity if I had a complete battery box, I could experiment with it. 😇

[@OffGridGarageAustralia]

Do they have a manual for the BMS settings? I could not find one online. I'll ask them... Not that you would put something like this on the website in the BMS section, right? 😉

[@GreenHomeEnergyBB]

Thanks for all these informative videos. But why don't you leave the active balancer in the rack? If the passive one is too slow, it can support it or not?

[@pau1phi11ips]

Because the active balancer doesn't turn off at a low voltage and will mess up the pack.

[@Ericcando81]

@@pau1phi11ips That is not right. I control an active balancer via a relay from the Victron Smart Shunt. From SOC 90% it starts.

[@OffGridGarageAustralia]

Yes, you can control the active balancer manually or automatically. This was for testing the internal BMS of the Seplos battery.

[@pau1phi11ips]

@@Ericcando81 how is that not right? You literally just stated it needs external control for it to only turn on at a high state of charge.

[@bildad1234]

@@Ericcando81 Can you explain how to do this. How to automatically start active balancer via relay from smart shunt?

[@DavidBTB]

Have you thought about putting a beefy capacitor on your power supply to filter AC ripple? That "intermittent power supply" alarm is maddening.

[@OffGridGarageAustralia]

I have a 135Ah and 280Ah battery as capacitor. I don't thing an extra capacitor will make any difference in that regards at all. That warning does not come from the DC-ripple but occurs when the battery hits the set warning threshold of SOC. It can be turned of. It is a conservative setting in the BMS so the pack get charged to only 95%. Not really necessary with LiFePO4 but some people prefer to only charge to a certain SOC

[@TheRonskiman]

Actually you're at 40,400 subscribers 🙂

[@theboov3110]

Hello Andy, again great video! Together with your video from 1 year ago (testing 1 cell with 3,4 and 3,5 volt CV charging), I believe that, despite a low balance current, one can conclude that when absorption charging at 3,5 Volt (ie 14Volt voor a 4s configuration) for let us say 2 hours, the complete battery will being top-balanced by the CV of the charger. When for a 4s battery the absorption voltage is set at 14Volt and one cel is going to the max, the voltage of this “nerveus” cel will be limited to about 3,65Volt. While the other cels are still at about 3,45Volt or somewhat higher. Does this make sense? Beste groet, Peter.

[@theboov3110]

Sorry….I did not take into account that when one cel is reaching the top voltage, the current is tampering down and the other cells will accordantly wil lower their voltage. Resulting in a “master cell” that will be on top of the charging period. In other words this cell is prohibiting that the pack will be top balanced. I need an active balancer to add to my installation……….. OK Andy, great work you are doing and it is most inspiring for a lot of your followers, in this case yours truly! BR Peter

[@milan2931]

Thank you

[@USA-GreedyMenOfNoIntegrity]

no. don't do it.

[@OffGridGarageAustralia]

Damit, I'm missing out on these affiliate clicks 😒

[@bilalbhatti7549]

It'll balance off after it hits 3.56v and then it balances and trickle down to 98.5%

[@timos144]

Das sind "Plug in and forget" Batterien. Bei deinem ersten test hast du ja ein paar Zellen getestet, das waren genau die die dir danach probleme gemacht haben. Theoretisch müsstest jetzt noch so einen kaufen und ohne mit den Zellen zu spielen das ding zusammen bauen und testen. Auch ist es unüblich die Zellen von 2,5V bis 3,65V zu benutzen... Stell sie einfach beide in die Ecke, schließ sie an und lass sie mitlaufen. Guck nach einem Monat nach, wie es mit den zellspannungen aussieht und fertig. Ich selbst nutze ja die Pylontech. Anschließen, anschalten und vergessen. Läuft seit Jahren ohne Probleme, auch mit 100mA passiven balancer... so lang sie im "Normalen Bereich" betrieben werden und nicht unteres minimum oder oberes maximum um sogar den balancer zur Schutzabschaltung zu zwingen gibt es keine Probleme.

[@OffGridGarageAustralia]

Danke Dir Timo. Das wird aber nur funktionieren, weil das BMS nur bis 95%SOC laedt und dann das Laden abschaltet. So ist die Standard Config. Dabei wird ein gewisser Top Buffer geschaffen welcher eine sehr hohen Spielraum fuer Zellen laesst. Daher schaltet das BMS nicht ab und geht in irgendwelceh Fehlermeldungen. Aendere mal dein Settings und lade bis 58V. Wuerde mich wundern, wenn das BMS nicht vorher abbricht weil das Delta so gross wurde und einzelne Zellen hoeger als 3.65V gehen. Die getesteten Zellen waren 13, 14, 15 und 16 in meinem Pack. Wir haben ja in einem der letzten Video alles nochmal Top Balanced, so dass das wieder ausgeglichen wurde.

[@philippesteindl3356]

Gawd I hate the negative Findings with this product. FINALLY; someone offers me a really cool case, without all this crappy cablesalad of all these open, dangerously unprotected DIY batteries and now you find bad points. Gaaaah....

[@WCO3]

You're missing your calling Andy. I think it's way past time for you to make You're very own, Peter BMS!

[@bboyda4399]

I am starting to think that balancing more than once a year is a waste of time. If it will give an alarm output for high deviation, maybe use that to turn of charging until it returns to normal.

[@TRS-Tech]

May be a good idea to get some 12v led bulbs or led strip for the bus bar area of the battery rack. Having decent light will help you a lot I think :) P.S. Ensure your LED lighting is at the right angle. Ensure you use a properly calibrated S.P.A.T. to check..... Very important 😁

[@OffGridGarageAustralia]

You don't want to handle a SPAT inside the battery rack! You could spill some of the precious juice 😁

[@USA-GreedyMenOfNoIntegrity]

remember when you see the warnings pop up on the screen, it is taking your charge amps down to 10A or less. Well, I wasted $400 on a bunch of junk. Thank goodness for JiKong and their new LCD screen.

[@igorybema]

If you own a EV you are used to see the charge amps are lowered as high the SoC goes. This is no difference and is for a good reason not to overcharge a single cell

[@USA-GreedyMenOfNoIntegrity]

@@igorybema I have nine other batteries that don't do this current limiting and they never overshoot.

[@OffGridGarageAustralia]

The BMS should not control charging. This is part of the charger and not a BMS task. It can however talk to the charger and make the charger to slow down if the battery temperature gets to high for example. We will get to this soon.

[@USA-GreedyMenOfNoIntegrity]

@@OffGridGarageAustralia Seplos is the only one that does this out of my ten batteries with different bms's.

[@igorybema]

@@OffGridGarageAustralia it does not control it. It only asks the charger for a lower charge if it thinks it is better. It is still up to the charger to honor this request or not. But only the BMS knows the invididual cell voltage and if one is at a higher voltage it is better to lower the charge current so the cell voltage will go down and let the others catch up. If the BMS had a high current balancing this would indeed not be necessary but I think this is exactly the reason why 150mA balancing is enough for the BMS, because it can ask the charger to lower the current at the top of the SoC.

[@awesomedee5421]

no frenching? that sucks.

[@awesomusmaximus3766]

My batts got their first full charge in 112 days

[@OffGridGarageAustralia]

Mine got down to 12% this morning. 45%SOC was the best I could see so far after the winter dip.

[@awesomusmaximus3766]

@@OffGridGarageAustralia Same ha ha

[@jasonbroom7147]

You start out the video showing a very small 20mv of deviation across 16 cells...and then you say you don't think this BMS is balancing? I'm more than a quarter of the way through the video and still trying to find the part where it "sucks". Charge to 3.4v or 3.45v per cell and don't obsess over such small deviations? Is anyone able to cite a peer-reviewed paper, showing what level of cell deviation is acceptable across packs of varying sizes? The only thing I have found is manufacturers stating 2% or less (3.65*.02=.073), so does that mean anything around 75mv of deviation is considered good? It seems to me like you are desperately trying to find something wrong and are disappointed to find that it's all working within perfectly safe and suitable parameters. This is not like your usual work.

[@marklazerson2281]

Please expand on why through your testing you seem fixated on multi amp balancing, there are 24hours / day apparently much better for battery health to take things slow surely?

[@igorybema]

I am with you. This fixation on multi amp balancing is too much. A active balancer is nice for a completly unbalanced pack but as soon as the pack is balanced a passive balancer as the seplos is, is good enough to keep it balanced for a very long time.

[@geraldhenrickson7472]

The EVE cells contain massive amounts of current. Balancing takes too long at a lower current. Mine balances at 4 amps and I wish it were 6 amps or more.

[@igorybema]

@@geraldhenrickson7472 But if you need 6 amps of balancing your initial top balance was wrong. There is no real usage situation where you would need 6 amp of balancing.

[@CollinBaillie]

150mA balancing makes sense when your cell is maybe 3400mAh capacity, and charging current on the cell is maybe 60mA (1000mA across a 16s pack). 150mA can counter that charging current. When your cells are 300,000mAh, and charging current can be 10,000mA (160A across a 16s pack) during bulk charge, perhaps 300mA per cel nearing the top (~5A across the 16s pack), 150mA is insufficient to counter that charge current. Multi-Amp balancing current is a must for these large capacity cells, because charing current is so high. For a balancer to keep a cell safe, it needs to be able to remove energy from the cell faster than the charger is supplying energy to the cell. There's also the consideration that cells should have a minimum charge current. At the end of the charge curve, once charge current drops to 0.1x the set charge rate, the charger is programmed to end the charge cycle. That setting exists, because that is the healthy norm for charging cells. To trickle charge the cells is said to be at least undesirable, and possibly detrimental to the cell. If your charge current is 0.5c, for a 300Ah cel, that's 150A. 0.1x 150A is 15A. You can see how 150mA is orders of magnitude below that 15,000mA charge cut-off current. If we say charge current is 0.2c, that's 60A (60,000 mA.) 0.1x that is 6,000 mA. 150mA is still orders of magnitude below that cut-off. These are very rough numbers, and someone with more experience with an actual system could give better figures. When you're working with cell capacity in the 100,000s of mAh, a 150mA balance current is.... insufficient... worthless... non-performant. It just doesn't work. It can't work, it's just too small. This is considering balancing-while-charging. If it's balancing while resting, it's just slow. The other point to consider is that these small current balancers are built this way, because they are actually burning power away as heat, via resistors. It's not possible to dissipate greater currents, because it would result in component failure, or necessitate the use of components which would make the design ungainly, impractical. They really are conceptually ideal for very small capacity packs, as the duration of balancing, heat generation, energy wasted etc are minimal. On these larger cell packs, they are an inappropriate design choice. Active balancing, using capacitors to shunt energy around make so much more sense. Balancing capacity, balancing duration and balancing losses are all much more suitably ranged for working with large capacity packs.

[@CollinBaillie]

@@igorybema This is a great argument for perfectly matched, near new cells. What if the cells you have aren't quite perfectly matched? What happens as cells change over the lifetime, and become unmatched? What if you buy used cells? Nothing is ever perfect. A balancer is simply a mechanism to counter real life variances, and ensure that your cels are kept within their safe region of operating, throughout the lifetime of the pack, with the most possible energy throughput across the charge cycle. I guess if you are happy to top balance and just rely on shrinking capacity due to slow changes in cell capacity, or perhaps routinely maintain that top-balance across the lifetime of the pack, a balancer is not needed.

[@PVflying]

Why do so many people seem to think fast balancing is essential? What are you all doing to your batteries to get them so out of balance on a daily basis, or are you just so impatient you can’t wait for passive balancing to complete? Seems to be an infectious form of insecurity which spreads among folks who come to believe that high balancing currents are needed. They’re not!

[@pau1phi11ips]

I had a Daly on a 280Ah 24V for a year. I needed to balance it last week as 1 cell was way out. It took an active balancer 12 hours. A decent current is necessary for this, otherwise it'd take days . Small balance currents are fine on small batteries, not these big ones.

[@descent8275]

most people get janky alibaba cells. sometimes you have a slight runner. without a higher balance current the whole bank would be unusable.

[@OffGridGarageAustralia]

Unless you have really high quality and well match, I mean really well matched cells, passive balancing with 100mA is not sufficient for high capacity cells. And this will then only work for the first few years. If they get older they spread apart and more balancing is necessary. As we have seen here in this video, I was very patient and gave the pack 2h time on a higher voltage (steeper area of the curve to make it easier) and the balancer did pretty much nothing. As I said, it was not a problem as none of the cells were peaking and going over the specs. But these passive balancers are not made for these cells. You also want to consider not to leave your cells at a higher voltage (for balance purposes) for too long and bring them down to a lower float voltage. The faster the balancer balances the sooner the battery can get to a lower voltage.

[@john_in_phoenix]

@@OffGridGarageAustralia The "small" balance works quite well on my grade B cells. The only time I use an active balancer is to top balance. Once you get over 3.45v, the cell voltage hits an exponential curve, and one cell will always "run". The truth is, you are chasing approximately a tenth of an amp hour difference, and putting unnecessary stress on your cells for that 0.1% difference. Most people charge on a regular basis, don't need to constantly play with voltage settings for the BMS and charge controller.

[@ronwest7930]

I bought used batteries from a bankrupt solar farm and many people talk about having weak cells. (usually just one) It sounds like a good idea to try and keep batteries balanced as best you can for the long run. or as Andy mentioned before, have a switch and do it once in a while.

[@typxxilps]

2 videos within 1 or 2 hours is a lot - fixing the pool and now troubleshooting SEPLOS again. I hope SEPLOS will listen as carefully as NEEY to get their mediocre BMS fixed and add a lot of improvements like the Balancing capability of the JK BMS or BT access instead of old wire connection. So disappointed that I had bought that SEPLOS BMS and their bad support. Luckily I did not buy their battery when they had made themselve suspicioius cause they always tried to sell me their full kit with their battery cells, those crappy 4 year old ones from 2019 they had shipped to Andy. If they do not act and improve they will be screwed soon. Lot of peoples had bought their battery kits and those are complaining about the mason kit in general - missing bits and pieces, poor quality at different spots or missing pieces and close to no support, too expensive accesories like a 20$ plus VAT plus shipping USB RS485 connector which is a simple USB ftdi adapter you can get for 3$ from aliexpress or 4 $ from amazon incl. vat and shipping.

[@OffGridGarageAustralia]

Yep, doing two videos a day now, soon four per day 😂 They were all scheduled in already so good for you if you watch both. You're getting the full Andy experience 😁 This all will be in my verdict video but I agree, they have to improve on some things and customer service is definitely a part of that. I cannot really complain but I seem to have a bit of VIP status because of the videos I pump out. Wait, why did they send me the old batteries then? 😮

[@mediocre_moto]

Looks to me like Seplos need to engage in someone to decipher and re-write some of the Chinglish so that it makes more sense to us Westerners. I'm sure some of those weirdly named settings may be of use, but I'd be hesitant to start randomly turning things on and off...

[@OffGridGarageAustralia]

And there is no setup procedure or guide who explains all the settings. It makes it really hard to understand what the BMS actually does.

[@evil17]

I agree, the lack of communication & Chinglish without explanation is unprofessional and makes the whole process a bit like a Rubiks Cube to figure out and work on. All data should be available on these BMS for individual tweaking purposes.

[@USA-GreedyMenOfNoIntegrity]

Just take your pick, roll the dice, be brave. Seplos only gave us 100+ different parameters.

[@USA-GreedyMenOfNoIntegrity]

@@OffGridGarageAustralia I downloaded a user manual. Typical jumbled up, hard to unferstand and written for the 18 different models over the last 2-3 years.

[@OffGridGarageAustralia]

@Juha Tuomala A universal front panel would be great so people can install their own BMS for example ;)

[@milan2931]

Off topic - comunication with JKBMS Question: "I have a question about wiring your BMS. It is possible to connect 8 BMS in series. Please see the pictures. Will there be a problem with bluetooth access if 8 BMS are together?" Answer: "Hello, our jkbms can not be used in series and parallel at present. Especially in series. That would lead to disastrous accidents. Please stop this dangerous use. Our BMS cannot withstand such high end pressure. I hope it's all right! Chengdu Jikong Technology Co., Ltd" Not serial - OK, understand. But not parallel? 🤔

[@CollinBaillie]

Inrush/Outrush current is probably a consideration. If each BMS is protected by a fuse or breaker to the bus, it is probably ok.

[@ricardomarcelino8388]

Batteries with different SOC when connecting in paralell, the inrush current for a millisecond can burn your JK. Not likely, but possible... They imperative on series, not paralell...

[@milan2931]

@@ricardomarcelino8388 I think too. In addition, there is only a floating voltage on each BMS, equal to the number of cells

[@milan2931]

@@CollinBaillie Each module have NOARK Ex9BP 150V 40A (module 16pcs cells). 10 modules serial, 512V 😁

[@upnorthandpersonal]

That should be changed by now. My diagram is on their site, which shows how to parallel with a class T fuse. Parallel is no issue with LiFePO4 - they just say that to make sure that people don't just do this with e.g. NMC cells where one pack sits at a much lower state of charge compared to the other, leading to large currents between the packs potentially damaging the BMS. Because of the flat curve of LiFePO4, this is not an issue with this chemistry.

[@launacorp]

This (the passive balancer BS) is the reason why I charge my bicycle battery as slow as possible as often as I can. So the % of balancecurrent to chargingcurrent is at high as possible. I would modify it but this is a leasing object so i can´t per regulation. Perhaps I modify the passive balance resistors to get lower resistance to increase the balance current... But you´re right: Why do they still use passive balance BS? It is so "2010 Style"🙄 PLS God let rain brains

[@USA-GreedyMenOfNoIntegrity]

You have good cells, believe me, its not Seplos!

[@USA-GreedyMenOfNoIntegrity]

Yes it was balancing with 150 mA usually about 75 mA on the two highest cells. you cannot connect a 4 A cell balancer along with the BMS balancer. It causes all kinds of conflicts. Been there done that.

[@OffGridGarageAustralia]

I have setup batteries with 4 balancers connected. No problem having any active balancer in parallel to the BMS balancer. Done this several times and works a treat.

[@batteryaddiction1848]

Your question to why not all together? Battery Cycles! All of the active balancers cause a charge / discharge cycle that ages the battery too soon. RE how slow the balancer functions - I think there are some settings that need to be tweaked to get to your balance to kick on at the levels your at. So in my experience with the BMS its kicks off the charge internally when it needs and performs the balancing. I think your too rushed since the final charging should be at the 150ma per cell for maximum absorption - which should taper off to zero once it is all full.

[@batteryaddiction1848]

In looking at the manual - Charge equalization at charge or float status. EQ V threshold is 3.350V and EQ V D is 30mv. All of these setting are changeable.

[@OffGridGarageAustralia]

Battery cycles are not a concern with LiFePO4 as we know and the active balancer should only be active at the top voltage of the charge cycle as we have tested. So that will be no additional stress on the batteries in terms of cycles.

[@USA-GreedyMenOfNoIntegrity]

"Take the initiative" yeah, that's where when you have junk cells, it lowers your charge current to 10 A which means you need about 10 hours of sunlight to charge your battery While the rest of my batteries are taking in anywhere from 10 to 30 A.

[@OffGridGarageAustralia]

The BMS should not lower the charge current. That is not what the BMS is for.

[@USA-GreedyMenOfNoIntegrity]

@@OffGridGarageAustralia Our Seplos reduces it to 10A. It's in their jumbled up user manual.

[@USA-GreedyMenOfNoIntegrity]

Oh yeah, if you have a cell that goes to 3.65 OVP, it magically goes to 100%, When it's really sitting at 90% like in my warranty returned Trophy 220C-1 battery.

[@pmacgowan]

Covid safe hug

[@OffGridGarageAustralia]

🤗

[@bilalbhatti7549]

You never answered

[@davidpatrick1813]

beer

[@udokag4]

The BMS doesn't work compared to the price

[@OffGridGarageAustralia]

No, it does not. I also thought I can buy a better BMS for that price. But let's see...

[@Irilia_neko]

Take off the BMS, and replace it by a jk-bms 🤣🤣🤣

[@BavarianSuperGuy]

YES do it and the Drama is ending ... 🤣

[@frejaresund3770]

Or the Neeeeeeeeeeeeeeeey mk4.