Low side switching is usually preferred for high currents because N-channel mosfets have lower power dissipation than equivalent P-channel mosfets due to N-channel mosfets having a lower Rds_on than their P-channel counterparts.
Good to see you on here upnorth. Always learn something from you when you post. I had the privilege of having you comment a few times on Will's forum in regard to long term storage of my LifeP04 battery in cold weather. Actually, your comments and resources you provided for me convinced me to leave the battery at the cabin during the cold weather months turning off ALL loads and leaving the SOC at around 50%. They did fine. No adverse effects that I can see. Capacity is the same, charges the same etc. Really respect your knowledge. Thanks for sharing it with us.
This. It makes perfect sense to switch the negative with the MOSFETs. However, the circuit breaker, which is externally accessible, not automated and is a disconnect / protection for the output of the overall pack, should be switching the positive.
You are absolutely correct. N channel have all that you stated and they are also more predominate in high current switching applications. I work with switch mode supplies everyday. As well as PWM audio class D. All of which have switched to al N channel mosfets. BMS on the negative and fuses go on the positive.
I don't see the point in repeating after you the flaws you noticed. But I see another one, BASIC: the price of sixteen blue cells with a capacity of 304 Ah, plus BMSs, plus mounting accessories is SURELY lower than those beautiful batteries. And this calls into question the economic sense of buying these beautiful Seoplos. Looking from this perspective, one can at most consider the features of the BMS, but also from a purely academic point of view - the detachable minus puts it outside the circle of interest of those who want to build the battery themselves. The only undeniable advantage of evaluating these batteries, as for me, is that I learned that there are such small internal fire extinguishers. Priceless information. THX!
Yes, I agree with your comment. Well, I really like the Seplos MASON DIY boxes and think this is the way to go if you want to build you own battery but not use a wooden crate or build a shelf yourself and shield it with aluminium sheets. You get a good metal box, the BMS and all accessories to build a good working battery.
@@OffGridGarageAustralia Indeed: Seplos MASON boxes are an almost ideal solution for someone who does not know, as I do, a man who is skilled welder-locksmith, ready to make boxes for individual banks exactly according to my requirements for a very moderate price. I think, better then Seplos, at least for me. :) But theirs BMS is interesting proposal!! Especially the one that DISCONNECTS PLUS! Now the funniest: the concept with the display and accompanying keypads and the on-off button and reset (through a small hole) and protection (preferably Noarc with remote shutdown function!) ON THE FRONT PANEL I invented as a first idea. Being very surprised that ALL manufacturers (even Victron!) construct the battery box so that everything is on one side. But all connections on the SIDE of the battery. Why on the side? Because physically disconnecting one battery box, for example for service purposes, when the connectors are at the back in a multi-storey system would be very cumbersome! Because convenient service access and systematic monitoring at regular intervals with an infrared camera are of paramount importance. In addition, on the side you can easily add a neat metal cover so that the cables do not create the impression of chaos. To be completely clear: my battery room will be built so that combustible materials will be limited only to the insulation of certified cables and certified Noarc electrical apparatus. (Let's make no mistake: there are no non-flammable plastics, only those with a much higher flash point.) My friends say: You are hysterical. I say: the elimination of risks is the main goal of the designer. And minimizing the risk of fire in a room where very thick tens of kilowatt hours of energy are accumulated is the MOST IMPORTANT goal. According to the principle: fate rewards the prepared (and I always add in my mind: and punishes the reckless!). That's why I was so delighted with small internal fire extinguishers, that's why the boxes for individual battery banks will be made of steel, fire-resistant tiles on the walls and fire-resistant doors, with a MANDATORY large fire extinguisher (15 - 20 kg extinguishing agent for electrical devices, of course!) next to this door! Nothing can ignite there and nothing can sustain the fire there. But even if one of the cells wanted to make an ugly surprise, there is a remedy in the form of a fire extinguisher. One whose important element of operation is the intensive cooling of the extinguished object. Have you ever seen an industrial high-current electrical switchboard and/or battery room? This is more or less how it is supposed to look in my performance: almost empty, only batteries boxes and electric busbars. At the entrance, the main power switch and always fire extinguisher. This is the pattern I am aiming for. It is not without reason that they look like this, it is not without reason that there are restrictive regulations, most of which are fire safety issues. More than one house in the world has burned down due to faulty electrical installations. In the case of the battery room, you must not lose sight of the fact that the currents in the battery room are (or can be) 100 times greater. That means 100 times greater risk. Greetings and thanks for the excellent work in the field of sharing information and experiences. Everyone will find something very interesting for themselves.
I really enjoy this channel Andy. I relate to you in a way Prowse and Poz don't quite get to, although I fully trust their opinions. You go Leagues further into the fun stuff for us nerds. Keep it up buddy! My plans to go solar in my own Box Truck/Mini Home begin in ernest this fall, and I'm so excited!!! GL to you and yours, Andy... Patrick
Yeah, I cannot watch a 7min review of a battery. There is far too much to explore and discuss. Even too much for one video, so there will be more testing with this battery. And the BMS of course!. The V3 BMS!
Electrically speaking, it doesn't matter which battery terminal is being switched since the metal chassis must be grounded separately anyway and neither DC terminal should really be directly attached to chassis and system ground but should remain isolated. The negative terminal is also the terminal where the charge originates from since electrons will flow from the negative terminal through the load to the positive terminal. All that generally matters is that you pick positive or negative to mount your switches and fuses and keep it consistent throughout the entire system.
I would be concerned, as noted in the video, if the negative is switched, the whole system might find a path to ground via one of the data cables. Those definitely aren't rated for the kind of currents involved
Another great video. Here they state 100A you need 3 AWG not 4 AWG (USA). Great looking battery. I want one that allows me to use EVE 280AH cells inside. And of course the breaker on the positive, and the back panels to swing out, and the soft touch on/off on the front. And I agree that the connections need to change. If you use a busbar on the back the charge and discharge will be like your DIY battery from the top down. While this is small for discharging the charging will be a bit slower for the bottom battery. How many can you stack? I also thought we were moving away from the 100ah batteries as you simply need too many. To replace your DIY battery you will need at least 10 of these. This adds more complexity. Seplos seems to like 1 step forward 2 steps back. I hope they can continue to move forward. Great box designs, good not perfect BMS. I find they are a leader in these, yet they have not blazed a trail that we all think hey that is perfect. Again thank you for what you do Andy!
Andy this Polos battery system needs more R&D then release it to market. Seplos engineers should of sent you prototypes to work the bugs out first. Love your videos & have learned so much about Lifepo4 batteries/cell design from you. You & Will Prouse are a great influence for the DIY battery builder folks like myself. Thank you so much & keep the videos coming.
I always tell them that: send me the pre-sales model so I can give feedback. There is a lot of cultural difficulties as they think it's already good enough. It may satisfy the Chinese market but exporting it to the world... It's not great most of the time.
I'm not a big fanboy of the pouch cells, I totally agree with the on/off button/switch on the front and the use of bus bar connections for connection between units.
Thanks for a great video Andy, was looking forward to it. A few of my thoughts: 1. Agree with the lack of the on/off button at the front. 2. I think the terminals are intended to be used with busbars, as you stated, but even if you stack the cables, the sides will support them and prevent damage to the terminal. 3. I think it is intended as more polished, home use / on display battery. That's why all the connections, breakers, and reset buttons are in the back, and it also explains the three types (rack,wallmount, stackable). 4. In the event of emergency, the battery will shut itself down and / or trip a breaker. When you get around to it, you will address the issue accordingly. That's why I don't think it's meant for tinkering. Rather set and forget type a battery. Also the crane you got is more commonly refered to as a hoist (folding hoist), cranes are usualy bigger and engine/motor powered, but it is not wrong per se. Btw: any idea what the price is going to be?
Andy, these look great and have some beautiful design in stacking but........ They look like they still are in the Prototype stage. Great Video............YAR!!
You can use the 'MX' part of the breaker to remotely trip the breaker. You can also use the 'OF' part of the breaker to individually alarm via the dry contacts. What you can't do is remotely turn back on so the wall once again comes into play.
from what Ive just seen I 100% agree with all your findings for me, having an easy acessable way to turn off each battery is a must. not only for testing but for safety. also, I have a feeling the balancer is going to be no good and the best way to fix it will be to install an NEEEEEEEEEEEEEEEEY inline as well, seems using the wiring thats there already will be the easiest way also, I'm sure it would of gotten to 5.1kwh if the cells were all fully charged because the balancer was doing its job better
Oh Andy a tip on those cranes, if your needing to raise the boom without anything hooked up just lift it to the hight you need it to be, or slightly above, hold for a few seconds and then it stays there
@OffGridGarageAustralia yeah I don't think they tell you, but it's a cheat I learned years ago. Yeah just by hand lift up, feels weird but give it a few seconds and it's good to go
Hi Andy and thank you again for this video, it's interesting to see the evolution of some manufacturers. Yes the design is nice, but many others are doing almost the same thing now.. concerning the choice of push cells, I think only economical for them, but not sure that they will benefit the end buyer? currently there are so many of them making battery packs, that the competition is really hard!! about the automatic fire extinguisher system, for me it's a gadget, and sincerely I think it doesn't particularly give confidence!! on the contrary because the average buyer, could think? it can catch fire! This is my opinion on this Seplos news battery pack Polo! As usual your videos and these comments are perfect and impartial! and that is important. Thanks Andy!
Thanks for sharing your thoughts. Always appreciate and looking for your feedback. Yeah, the fire extinguisher is more a gadget. Maybe OK for a small cable fire. But would you rely on it? Probably not. The product is missing some important key components and is not ready for market yet.
I have mixed emotions about this battery. It looks sleek and clean for sure. Love the fire extinguisher as well! I do like that the cables can be hidden but at the same time, these batteries shouldn't be set up in sight really. I definately agree about the problems you pointed out. No switch on the front. The breaker should be on the front for emergency access as well. But I do not agree with breakers and fuses on the negative. Always kill the live wire. Ground is just a ground. Definately not the best terminal to work with either but they are more user friendly compared to those special connectors on the other batteries though. And as for the pouch cells, that is a massive NO for me. They seem to be the most unstable and prone to issues. Still love to see companies are trying different things though!! And always enjoy watching the German Aussy man!! 😁👍🍻 Thanks for keeping us all in the loop for the latest and greatest!!!👏👏👏
Switching the positive line is standard, but switching the negative line is actually more efficient and cheaper. Your choices are: (1) Switch the positive with a P-channel MOSFET, (2) Switch the negative with a N-channel MOSFET, or (3) Have a charge pump on the circuit board to generate a voltage higher than the positive, and switch the positive with a N-channel MOSFET. P-channel MOSFETs have a higher drain-to-source resistance (Rds) than N-channel MOSFETs. That's why N-channel MOSFETs are more efficient. N-channel MOSFETs basically just work better... they have significantly better electron mobility. So, for example, high-end switching power supplies will actually use N-channel MOSFETs to switch both the high side and the low side but it takes a special circuit called a "bootstrap circuit" to make the high-side N-channel MOSFET actually work. But you nailed the potential problem. If there is an alternative sneak path to the battery negative, switching the negative doesn't break the circuit. Sneak paths to the battery negative are a lot easier to mistakenly create than the sneak paths to the battery positive. However, fully enclosed batteries with no exposed "real" battery negative can utilize negative-side switching safely.
Yes, thanks for this explanation. Up North and Personal said the same below about the N- and P-Channel FETs. You really need to ensure your coms cables are all isolated so there is no issues if the BMS turns off. It could cause a cable fire otherwise.
I like the case look, but that is about as far as it goes. And, you showed their pouches didn't even meet their 100ah specifications. And, you are right, the units do need On/Off switches immediately available on the front. As for the panel covers on the back, they could be left off but that would eliminate a safety factor. You identified a lot of the things that I also noticed. The Seplos Batteries look good, but I think I'll hold off from buying them for the moment. I can put other types of batteries in a rack with a door and get the same type of safety factor, be able to separate and pull whole battery with less trouble, and replace a bad cell when its needed. I buy my equipment using these characteristics...reliability, availability, maintainability, and dependability, not how good looking someone has painted their Yugo. Thanks for the review.
If their V3 BMKS would have a decent and working balancer which could handle the battery, the cells would have been top balanced and we would have reached the 100A. I'm editing the Seplos V3 BMS video right now. That will be an interesting discussion.
Agree ... safety issue with the breaker access. It would be nice with a smoked plastic cover that you could lift up and have access to breakers and resets
Looks really nice. The wheels are a nice touch as well. Too bad about the poorly reachable components and reset switch, but this also has advantages when someone is cleaning or watering the plant on top. I stopped counting the times switches on my audio setup were accidentally pressed, and even the speakers have some damage. Cleaning live charge wires, circuit breakers and reset switches is not good. So this system also has a high WPF next to it's high WAF.
Yeah, I know what you mean. It is build in a safe way but a bit too safe in some ways. I would not like a battery in my living area (and it is not allowed in AU anyway), so the WPF is not too important.
23:14 Those "Tesla powerwalls" look like they have Seplos branding on them. Switching from switching the positive to switching the negative probably removed the need for a high-side n-FET driver and high-side current sense. On the communication ports, I would think that they would be galvanically isolated - otherwise turning off the circuit breaker in one of the batteries would cause one of the wires of the RS485 cable to become a current carrying conductor, which isn't going to end well. Looking at a post on the Victron forum, the unswitched negative requirement was for old MultiPlus-II inverters etc, where presumably the VE.Bus interface was referenced to the DC negative.
Very cool Andy. Huge design improvement in several areas, but having the main breaker burred behind a panel in the back of the unit rather than on the front is not my thing.
@@OffGridGarageAustralia The other concern I have with many of these systems is that if breakers with small contacts with minimal interrupting force on those contacts are rated to interrupt thousands of potential amps and won't weld closed on a major short circuit? I've seen industrial AC breakers rated at 50,000 amp interrupting capacity have one or more contacts weld closed and cause a panel fire. Most breakers are intended for overload protection rather than short-circuit interruption, my preference is always to have a fuse for short-circuit protection, especially in something intended to be operated in a home or living space rather than a detached garage or out-building. Some may argue that the BMS is a second safety for short-circuit, but they are solid-state switch that can fail closed rather than open under short circuit. Last month, a neighbor asked me to inspect his expensive e-Bike that had it's wiring literally vaporize and its flame-retardant plastic battery box catch fire due to a short in a battery connector. The Bike was charging in his garage under his bedroom. The ebike Battery had built-in Battery Management System board that failed to prevent the massive short circuit, that resulted in a dangerous and catastrophic fire. That bike had a Li-Ion rather than LFP battery, and as such, my neighbor is lucky that the battery pack cells did not catch fire which could have placed his home and family at risk. Yet another example in support of my contention for fuses as a safety design element in high-current battery applications.
Thank you for showing us this beautiful and stylish new battery, however, like your good self, I prefer to be in charge of the accumulator in fact I have just received two Seplos BMSs and expecting 16 304Ah cells for the construction of at least one of them to start with in addition to the 100Ah already in the system. As far as the fire extinguisher I'm not worried because I will construct a large one for the solar shed also feeding directly onto some components based on what I used to build for my competition Porsches. Thanks for sharing, I must admit that it really does look the part.
Hi Andy! 1) It's cheaper and simpler to disconnect the ground. You can use N-MOSFETs instead of P-MOSFETs. N are a little more efficient, but the simpler/cheaper angle is what the makers go for. 2) I bet if you jet forward 5 years most of these rack-battery systems will ALL be pouch based. I don't see much need for swapping out single cells. If the batteries are good quality none are going to need replacement until they're all swirling the drain. Besides those who are happy to over-pay for pre-built scrawny capacity rack mount batteries are not the type users to dig into a battery to do a cell replacement anyway. Here come the pouches! (yuck) Three of my 400Ahr batteries are pouch type...
The New BMS Studio software (battery monitor) looks good but i was not able to connect to a v2 10E BMS. There is also a new Firmware for the v2 10E bms 16.6 but i found no documentation about the changes.
As usual Andy great thoughts and initial review. Great looking battery pack, but as you point out some disappointing practical functionality issues. Strikes me as a glossy marketing package with some serious serviceability issues. Lost me at pouch cells I'm afraid.
They could never explain why they went with pouch cells🤷♂️ And the other flaws I pointed out... not so great. I like the Jaki battery more as it ticks all the boxes.
Seplos BMS Welcome you to gardening with Andy. Not going to happen! My wife has her greenhouse, I have my battery shed and I'm not putting geraniums in there. I appreciate the way you highlight the positive and the negative features equally, whether it's the hardware or the software, it makes for a very informative video. Thank You.
Great fire extinguisher concept, would be nice to see this as a stand alone product for wider battery community...is there a maker name underneath it?? Loved that you talked about access to breaker at bottom if stack, niggles & design issue's!
I left a link in the description where you can get one. Not sure how efficient they are though for such a battery. It's more for a small cable fire, I guess...
You do a great job with your evaluations. I am still looking at setting up a solar system in the next 12 months. Looks great, but unfortunately, the cells are not servicable. What is the expected cost of the battery shipping, etc? Does the software have a reset function in case you screw up the settings? RS485 & CAN require an end of line 120 ohm terminator resistor. How is this set on the battery? Is the BMS available separately? Keep up the good work.
Thanks for your feedback and kind words. Yeah, a lot of open questions. I will address some in one of the next videos about the BMS V3. CAN works for me without termination. I use the 3m CAN cable from Victron and had no problems so far. If the cable length is short, I guess it is OK. The BMS definitely have a termination on-board.
Hey @offgridgarageaustralia great review, thanks for the detail. Just my 2 cents on why pouch, I suspect pouch cells are becoming cheaper than prismatic (likely due to increased pouch cell production in China for EV batteries). Pouch cells can be packaged smaller than prismatic or cylindrical BUT it really depends on the decisions made by the design engineers.
I think i prefer every thing at the front. If you want to install this into a tight location you may not be able to get around to the back. Needing to pull the unit forward just to turn it off? Whilst those with all the connections on the front don't look as neat, they make me feel I would be able to check/fix etc easier than this unit. Also I worry about having to replace the whole pack as one unit. feels wrong. Great video as always
@@davidcassidy2944 You have veered off topic; I mentioned nothing about switches or cabling. Note your words are "Also I worry about having to replace ..."
in all battries and inverter the negative is switched and positive is always connected because under load the negative wire of dc current get higher temp mostly than positive. and flow of electron is from negative to positive, its my observation.
Pouch cells are a lot cheaper 😅 The APP can be used by anyone easily. So they might be afraid, that inexperianced users do mistakes. But I think it should be public nontheless. Always some nice supprieses and new tech at your chanel...that is sooo good!
Thanks, my friend. The app allows me to change the inverter protocol with one click and no confirmation 🤦♂️ Even while swiping up and down, I accidentally switch it to something else without noticing. A few minutes later, the Cerbo started complaining 😄
i like the idea of the rack mount and stackable but yet no one seems to do controller inverter hybrid etc units to rack or stack with them unless you look at the portable units that stack seems a big hole in the market
Even Victron allows in the connection guide "Wiring Unlimited" switching or fusing the negative cable. You just have to do it the right way. Some installation have a main switch and/or a main fuse in the negative line, because there is no danger touching it or make an accidential connection with the chassis or other grounded parts. The shunt is also in the negative cable and there is no special isolation necessary. There may even be a regulation that requires to have a switch in both positive and negative. So Victron gives a recommendation, but it isn't mandatory. This may be because some people have fried the communication ports by switching only one component of a paralleled/split setup and not all of them concurrently. But a better solution would be to use galavanic isolated communication ports. This would avoid such problems alltogether. Regarding the whole system: - I am a bit disappointed that it doesn't have active balancing. - Pouch cells are probably a bit cheaper than prismatic cells. - Failed LiFePO4 cells normally fail with high resistance. So paralleling them without fuses is no problem. - The build doesn't seem to be fully thought through (connectors, power button, cable duct, ...) - Connecting with a copper bar would mean addeing about 35 sqmm for each box. This will get very thick with more than a few boxes. - To avoid unequal charging/discharging + and - connections must be placed at opposite sides. - It has a nice appeareance, but who would but this battery into the living room. Then the Inverter and other components would have to be placed also in the living room. An they have a totally different design and noisy. This will have a very low WAF. All in all this isn't the burner for me.
In the Luna2000 Battery from Huawei there's also an integrated fire extinguisher, they're around since 2021. And i think you missed the fuse in the positive lead in the battery, directly in the corner.
And Andies sickness continues. A new battery, so now we will have to build a new roof so we can install more panels to charge them. A nice looking battery, but it needs some improvement. A switch on the front for sure. As for the cells, it would be interesting to see what exactly is inside a prismatic cell. I would think it is just a hard case stuffed with a pouch cell. So by using pouch cells, it reduces the cost of these batteries.
If it's not top balanced & discharged below 2.5v then the low voltage cell & voltage drop from high current discharge will report less usable capacity. A few more charge cycles to see if the cells become better balanced. Would it help to use ~1.1A after atleast 1 cell has turned the balancing on?
I like the stacking idea, but for me, the battery would have to: 1) be in a rock solid case that can take 20 years of stacking 2) lowest base with the caster wheels needs to be an industrial life type, where you can bring the wheels up when not used, so the whole thing rests on the metal base, never the wheels. Also, a wheel rubber that survives 20 years without falling apart after 7 years due to loss of softeners 3) absolutly safe. No openings, where a coin could drop into and wreck chaos etc 4) upright prismatic cells for easy maintenance and trust into the cells liquid never leaking 5) a 4A balancer without need for hacking in a neey 6) displays on each module an dproper switches 7) perfect insides, with proper cabling, warming pads for winter etc 8) 1C standard discharging with 6000+ cycles 9) small and high capacity variant, so smaller homes can also reach 200A+ 10) maybe even a HV variant, since deye now has the HV hybrid
I guess the password issues is likely down to users Vs installers. I suspect they expect the installer to set up the battery from their laptop and then the customer can just view it in the app. Most of the time you don't want customers being able to change settings. Advanced users like yourself will be happy to change settings via a computer anyway.
As a traditional Seplos = it has potential, BUT... , it's not a finished development for practical use... (I expect it will be similar for the new BMS with the new software.) All the problematic things you listed should be improved and changed by Seplos. It would definitely need a prismatic serviceable battery cells. Basically, just the box itself is interesting from a visual viewpoint, and even that would need to be changed and finished for better everyday use.
I think you may have done seplos customers a disservice - if you have convinced them to make those Victron parameters user set rather than calculated by the BMS. The charge voltage should be calculated and the charge current and discharge limits also should change depending on battery state.
Hello, I watch a lot of your videos and I also use batteries with BMS SEPLOS that I assemble myself. A question: what do you recommend as a method to balance the cells when they are received and used for the first time?
Thank you for your feedback and watching my videos. If I buy all cells from one source, I would just install them in series and connect the BMS. Charge them up and decide later if they need any balancing. Either the BMS can handle that balancing or your can temporarily install an external active balancer.
Are parallel cell pouches a potential problem? I would have thought they would be ok - essentially looking after each other. Maybe a temperature sensor on each cell if you are being paranoid is all that is required. Note most cars have 2 pouch cells - some have 3 - some like porche have 4 pouch cells.
What happens if one is faulty? I'm not a big fan of paralleling batteries or cells without further safety measures. Parallel battery cells in cars have individual fusing, I believe. At least Tesla has.
I have an older LG Chem 10kw battery, can I plug one of these together and achieve 20kw Can you try daisy chaining several brands together, will they communicate with each other?
Yes, you can operate batteries in parallel, if they have the same voltage and similar chemistry. No, they most likely won't communicate together. RS485 is a standard (physical layer) they all use, but the protocol is different.
Im not a fan of the switch at the back, for a clean install it would most likely be close to a back wall, levelled and off the castors, which would make access to the reset and switch had to access. it wouldn't have been hard to design a recessed front switch and reset button at the design stage.
@@MrHoolign Some companies may stop sending me sh!t because of these reviews 😂😂😂😂 I always tell, I'm not sales channel, I do reviews and if your product sucks, you will be in deep sh... I'm not after the perfect battery or BMS or so, but I have provides so much feedback to Seplos and they still come out with such products which lag simple design logic (breaker at the back) and use cheap components (these terminals🤦♂). They technicians all watch my videos so they should know what the community wants. And they should ask before they build.
@@OffGridGarageAustralia 100% with ya! i more meant that you will be upgrading and designing new stuff and projects (car port?? haha) for the foreseeable future. I got a $100 that says there will never come a day where you say "There we go! All projects are done! Let's sell the tools!" lol Love ya Andy, and thanks for the interaction, It means alot!
@@OffGridGarageAustralia and that explanation is why this community loves you man... don't ever stop the head shaking and the "Not Good" lol.... copyright that sh!t haha
After all the LG batt fires and recalls I’m not 100% happy using these yet.. they also have much shorter cycle life and prone to thermal runaway.. I do like that the size to power is much smaller thou so less weight, but as you pointed out if there was a cell that needed replacing it’s not easy and not good as renewable with lots of waste
I guess, you can take the battery apart and re-use the working cells in case one gets faulty. The question is though if they are going to do it or it goes to either landfill or recycling. It is a bit like with welded terminals, great from one perspective but not ideal from a maintenance point. The Jaki batteries are great therefore, ticking a lot of boxes.
The password for wireless connections not made public makes perfect sence. As changes can be made wirelessly on bluetooth where wired requires access to your battery. Think someone changing settings from the road in front of your House or RV. I'm in a boat yard i see many bluetooth connection to systems around me with default passwords.
i really love watching these videos, i will be changing solar inverters soon, i am highly considering the new SMA inverter that just released since i already have a sunny boy, only down side is that they all want high voltage batteries, do you have any information or knowledge about the seplos batteries that you can run in series for high voltage?
SMA is great. They are coming from my hometown in Germany. I actually know the founders and when they started their business back in the 80s out of an garage. I have seen the HV batteries on their website. This is nothing I can test any more because too dangerous and certainly not DIY any more.
@@OffGridGarageAustralia I agree..... I'm torn because I'm not sure of another hybrid inverter to go with, most seems to be Chinese such as EG4, and they might be great but they are all so new...
hi andy i also have 2 packs in // with it's bms3.0 i'm disappointed because i can't exceed 53.3v in load + your rs485 connecting cable why is it in the middle? on your master battery next to the victron cable? thank you for your answer andy
Thanks Patrick. It depends what RS485 adapter you have. Only their newest one (apparently) works in both RS485 ports on the back. My older one (came with the MASON box) works only with the first RS485 port. I'll explain this in the BMS video soon.
Hi andy, from not sunny at all UK. Can you help me with the seplos studio software please. I have usb on com3 and rate of 19500 but what are the other parameters as i can't get it to work.
Hi Andy, a bit off topic but I wonder if you could help me. On the JK-BMS 4S-8S edition there is the RS485 socket. I have googled RS485 to try and buy a plug to connect to this socket but cannot find the plug type for this socket. Do you know the plug type that I am looking for? Thanks.
I have read it somewhere in the DIY forum either here diysolarforum.com/threads/rs485-to-usb-cable.47837/#post-684039 or here diysolarforum.com/threads/hankzor-jk-bms-with-screen-and-power-button.33267/page-5#post-491377 If not, ask Up North and Personal. He knows...
All BMS do that though. The V2 is still on their website, so fingers crossed. So far only the V1 with FW 2.8 is working, not perfect, but still workable.
I think it would be a good thing, if they put the breaker into the positive wire. As this breaker can be triggered remotely (by the bms) there would be then a complete disconnection of both poles. Is it veryfied that the extinguisher contains CO2 ? I hope they don't put halon in it....
@@vlapr0571 Only a bit is connected right now, but once finished, I hope to have 100kWh permanently connected for the off-grid system. I still need more solar though...
The first priority must ALWAYS be 100% practical functionality for every day and only then the design styling, if the opposite is the case, as here, it is not good.
Polo are def not for me.. Like the masons for : Use standard and servicable cells Hate the terminals (small) and connectivity in the ( hard to reach) App is useless Does the bms studio work on the 10e version ? Is v3 compatible with the 10e ? The 2a active balancer board is a seperate purchase.. What makes that different to a 10e and a neey ? Look forward to your tests andy, but so far i only see downgrades from my 280/10e kits
@@Tom111060 I'm not expecting this tiny extinguisher to handle a battery fire at all. It may be useful for a small cable fire inside the box though. If it works.
The reason for a non public p/w for wifi, is that anyone can change your settings, where on your computer.. they would have to enter your home to get to your computer.
@@OffGridGarageAustralia yeah cool, i only ordered mine in may, it might be faster to you than to us, keep it up mega cool channel helped me a lot when setting up my memory with the seplos bms
It seems like its not serviceable. and it looks like the stack will be limited in current based on the size of the last terminal. which kind of limits it maybe... unless you break out leads from each which kind of negates the safety benefit i think. Or maybe im just stuck in the past :)
Please, please, test the fire extinguisher......get local cfs on standby in the interests of science. I had an early version of byd bbox battery that failed. So I took it to my farm and put a .223 round through it. It swelled and burped but never caught on fire even with a bullet in it
Not sure if the CO² does any good if the cells really burn. The exothermic reaction will release oxygen from the P-O bond which can fuel the fire without any external oxygen. This is not as pronounced as in NMC cells where the Co-O bond breaks more easily, but this fire extinguisher might not be more than a gimmick.
The decomposition temperature of LiFePO4 sits around 600C if I remember correctly. You'd need one heck of a reaction to make this sustained in a battery like this - which is why LiFePO4 does not typically suffer from thermal runaway like e.g. with NMC unless an additional heat source is introduced.
@@keyem4504 The one reason I can think of is that a spark could potentially set venting electrolyte on fire. In that case, the CO2 extinguisher would be useful . I've seen some people have cells vent, and these pouch cells likely vent faster than a prismatic in case something goes very wrong.
It is a bit questionable but the CO2 would at least stop any auxiliary fire from circuit board, components, plastic, and wiring, so in that regard it might be reasonable. But it won't stop the batteries themselves. Stil, a LFP cell just doesn't runaway for very long so if nothing else catches fire or is put out by the CO2, it is all good.
I assume that the fire extinguisher won’t work well. If you have a thermal runaway of this type of cells, you don’t have a big problem with oxygen, but a problem with thermal capacity. So you have to use a extinguisher component which is capable to dissipate the generated heat for hours. Just a shot of CO2 will not do much. Just my 2 cents …
LiFePO4 generally does not suffer from thermal runaway: you have to introduce an additional heat source to make it happen. Just puncturing a cell, or whatever, does not cause thermal runaway, even if the venting electrolyte can be set aflame with an additional spark. This is likely why the extinguisher is there. If these were NMC, it definitely would be useless, since that chemistry does experience thermal runaway easily, and no CO2 extinguisher can do anything about that.
I am impressed with the clean look, but I am disappointed with the functionality of the new packaging. 1. They definitely need an On/Off switch on the front. 2. The circuit breaker location is completely useless. Not only is it difficult to get to in the event of an emergency due to the panel covering the back, once the battery is positioned against the wall and the casters are locked down, how the hell do you get at the back in the event you need to get to the CB. Maybe a better location would be on the side. It would not detract from the appearance/presentation. 3. The design allows the use of a busbar to join the batteries, but a M6 screw and such a narrow terminal, it will make it difficult to use a busbar that will carry the combined current of all the batteries, particularly if you are using 3 or more batteries. 4. The specification says the charge temperature is 0 -> 40 degrees C. Considering that charging will occur during the day when it is likely that temperatures could exceed 40 degrees C. If you consider that the temperatures being experienced around the world have exceeded 40 degrees in many locations and it has also been predicted that in Australia we may also experience these high temperatures, how will these batteries deal with these high temperatures?
Thanks for your email and comment Chris. Great points! I didn't see the temp settings for charging the battery. I have reached 40° in my battery shelf last year.
Low side switching is usually preferred for high currents because N-channel mosfets have lower power dissipation than equivalent P-channel mosfets due to N-channel mosfets having a lower Rds_on than their P-channel counterparts.
Good to see you on here upnorth. Always learn something from you when you post. I had the privilege of having you comment a few times on Will's forum in regard to long term storage of my LifeP04 battery in cold weather. Actually, your comments and resources you provided for me convinced me to leave the battery at the cabin during the cold weather months turning off ALL loads and leaving the SOC at around 50%. They did fine. No adverse effects that I can see. Capacity is the same, charges the same etc.
Really respect your knowledge. Thanks for sharing it with us.
@@jws3925 Thanks! Just glad I could be of help. (YT seems to remove some of my comments, so this is the second time I try to reply to you - sigh...)
This. It makes perfect sense to switch the negative with the MOSFETs. However, the circuit breaker, which is externally accessible, not automated and is a disconnect / protection for the output of the overall pack, should be switching the positive.
@@CollinBaillie Absolutely - fuses/breakers go on the positive.
You are absolutely correct. N channel have all that you stated and they are also more predominate in high current switching applications. I work with switch mode supplies everyday. As well as PWM audio class D. All of which have switched to al N channel mosfets. BMS on the negative and fuses go on the positive.
Thank You Andy. for your video..Withou you it's very difficult to finish the configuration of this BMS. You are my savior😇
I don't see the point in repeating after you the flaws you noticed. But I see another one, BASIC: the price of sixteen blue cells with a capacity of 304 Ah, plus BMSs, plus mounting accessories is SURELY lower than those beautiful batteries. And this calls into question the economic sense of buying these beautiful Seoplos.
Looking from this perspective, one can at most consider the features of the BMS, but also from a purely academic point of view - the detachable minus puts it outside the circle of interest of those who want to build the battery themselves.
The only undeniable advantage of evaluating these batteries, as for me, is that I learned that there are such small internal fire extinguishers. Priceless information. THX!
Yes, I agree with your comment.
Well, I really like the Seplos MASON DIY boxes and think this is the way to go if you want to build you own battery but not use a wooden crate or build a shelf yourself and shield it with aluminium sheets.
You get a good metal box, the BMS and all accessories to build a good working battery.
@@OffGridGarageAustralia Indeed: Seplos MASON boxes are an almost ideal solution for someone who does not know, as I do, a man who is skilled welder-locksmith, ready to make boxes for individual banks exactly according to my requirements for a very moderate price. I think, better then Seplos, at least for me. :) But theirs BMS is interesting proposal!! Especially the one that DISCONNECTS PLUS!
Now the funniest: the concept with the display and accompanying keypads and the on-off button and reset (through a small hole) and protection (preferably Noarc with remote shutdown function!) ON THE FRONT PANEL I invented as a first idea. Being very surprised that ALL manufacturers (even Victron!) construct the battery box so that everything is on one side. But all connections on the SIDE of the battery. Why on the side? Because physically disconnecting one battery box, for example for service purposes, when the connectors are at the back in a multi-storey system would be very cumbersome! Because convenient service access and systematic monitoring at regular intervals with an infrared camera are of paramount importance. In addition, on the side you can easily add a neat metal cover so that the cables do not create the impression of chaos.
To be completely clear: my battery room will be built so that combustible materials will be limited only to the insulation of certified cables and certified Noarc electrical apparatus. (Let's make no mistake: there are no non-flammable plastics, only those with a much higher flash point.) My friends say: You are hysterical. I say: the elimination of risks is the main goal of the designer. And minimizing the risk of fire in a room where very thick tens of kilowatt hours of energy are accumulated is the MOST IMPORTANT goal. According to the principle: fate rewards the prepared (and I always add in my mind: and punishes the reckless!).
That's why I was so delighted with small internal fire extinguishers, that's why the boxes for individual battery banks will be made of steel, fire-resistant tiles on the walls and fire-resistant doors, with a MANDATORY large fire extinguisher (15 - 20 kg extinguishing agent for electrical devices, of course!) next to this door! Nothing can ignite there and nothing can sustain the fire there. But even if one of the cells wanted to make an ugly surprise, there is a remedy in the form of a fire extinguisher. One whose important element of operation is the intensive cooling of the extinguished object.
Have you ever seen an industrial high-current electrical switchboard and/or battery room? This is more or less how it is supposed to look in my performance: almost empty, only batteries boxes and electric busbars. At the entrance, the main power switch and always fire extinguisher.
This is the pattern I am aiming for. It is not without reason that they look like this, it is not without reason that there are restrictive regulations, most of which are fire safety issues. More than one house in the world has burned down due to faulty electrical installations. In the case of the battery room, you must not lose sight of the fact that the currents in the battery room are (or can be) 100 times greater. That means 100 times greater risk.
Greetings and thanks for the excellent work in the field of sharing information and experiences. Everyone will find something very interesting for themselves.
I really enjoy this channel Andy. I relate to you in a way Prowse and Poz don't quite get to, although I fully trust their opinions. You go Leagues further into the fun stuff for us nerds. Keep it up buddy! My plans to go solar in my own Box Truck/Mini Home begin in ernest this fall, and I'm so excited!!! GL to you and yours, Andy... Patrick
Yeah, I cannot watch a 7min review of a battery. There is far too much to explore and discuss. Even too much for one video, so there will be more testing with this battery. And the BMS of course!. The V3 BMS!
Electrically speaking, it doesn't matter which battery terminal is being switched since the metal chassis must be grounded separately anyway and neither DC terminal should really be directly attached to chassis and system ground but should remain isolated. The negative terminal is also the terminal where the charge originates from since electrons will flow from the negative terminal through the load to the positive terminal. All that generally matters is that you pick positive or negative to mount your switches and fuses and keep it consistent throughout the entire system.
Yes, from a technical perspective. Although regulations say, switch the positive and leave all negatives connected as common ground.
I would be concerned, as noted in the video, if the negative is switched, the whole system might find a path to ground via one of the data cables. Those definitely aren't rated for the kind of currents involved
Another great video. Here they state 100A you need 3 AWG not 4 AWG (USA). Great looking battery. I want one that allows me to use EVE 280AH cells inside. And of course the breaker on the positive, and the back panels to swing out, and the soft touch on/off on the front. And I agree that the connections need to change. If you use a busbar on the back the charge and discharge will be like your DIY battery from the top down. While this is small for discharging the charging will be a bit slower for the bottom battery. How many can you stack? I also thought we were moving away from the 100ah batteries as you simply need too many. To replace your DIY battery you will need at least 10 of these. This adds more complexity. Seplos seems to like 1 step forward 2 steps back. I hope they can continue to move forward. Great box designs, good not perfect BMS. I find they are a leader in these, yet they have not blazed a trail that we all think hey that is perfect. Again thank you for what you do Andy!
They always safe one the cable size. The Gobel power battery uses 2AWG cable for their built. And, why not!?
I'd recommend cutting a holes in the backing plate. A square hole for the breakers and a small hole so you can reach in for the reset button.
Laser cut a square hole in the back panel for access (with rounded corners of course)
I have a hole punch. Do I punch another hole for the reset button and the network ports? Undecided 😁
Andy this Polos battery system needs more R&D then release it to market. Seplos engineers should of sent you prototypes to work the bugs out first.
Love your videos & have learned so much about Lifepo4 batteries/cell design from you. You & Will Prouse are a great influence for the DIY battery builder folks like myself. Thank you so much & keep the videos coming.
I always tell them that: send me the pre-sales model so I can give feedback.
There is a lot of cultural difficulties as they think it's already good enough. It may satisfy the Chinese market but exporting it to the world... It's not great most of the time.
I'm not a big fanboy of the pouch cells, I totally agree with the on/off button/switch on the front and the use of bus bar connections for connection between units.
All I know these manufacturers take note when Andy does a review and for the good too🇦🇺🤙🇦🇺
And I'm providing a lot of feedback their way as well. Sometimes it works, like with the NEEY.
Thanks for a great video Andy, was looking forward to it.
A few of my thoughts:
1. Agree with the lack of the on/off button at the front.
2. I think the terminals are intended to be used with busbars, as you stated, but even if you stack the cables, the sides will support them and prevent damage to the terminal.
3. I think it is intended as more polished, home use / on display battery. That's why all the connections, breakers, and reset buttons are in the back, and it also explains the three types (rack,wallmount, stackable).
4. In the event of emergency, the battery will shut itself down and / or trip a breaker. When you get around to it, you will address the issue accordingly. That's why I don't think it's meant for tinkering. Rather set and forget type a battery.
Also the crane you got is more commonly refered to as a hoist (folding hoist), cranes are usualy bigger and engine/motor powered, but it is not wrong per se.
Btw: any idea what the price is going to be?
Thanks, these are great points.
BUT. It's a crane! 😉
Looking forward to seeing the Seplos reasoning for saying pouches are better than prismatic cells. Thanks again for doing such a great review.
Andy, these look great and have some beautiful design in stacking but........ They look like they still are in the Prototype stage. Great Video............YAR!!
Yes, I would not have put them on the market like this either...
You can use the 'MX' part of the breaker to remotely trip the breaker.
You can also use the 'OF' part of the breaker to individually alarm via the dry contacts.
What you can't do is remotely turn back on so the wall once again comes into play.
Of with both features are not connected. It's just the main cables in and out.
from what Ive just seen I 100% agree with all your findings
for me, having an easy acessable way to turn off each battery is a must. not only for testing but for safety.
also, I have a feeling the balancer is going to be no good and the best way to fix it will be to install an NEEEEEEEEEEEEEEEEY inline as well, seems using the wiring thats there already will be the easiest way
also, I'm sure it would of gotten to 5.1kwh if the cells were all fully charged because the balancer was doing its job better
The balancers are always the weak points of these BMS. If they would have 200mA, it would be actually useful. But here...you won't believe it 🤦♂️
Oh Andy a tip on those cranes, if your needing to raise the boom without anything hooked up just lift it to the hight you need it to be, or slightly above, hold for a few seconds and then it stays there
By hand? I didn't know that. I read the manual... not all of it though.
Thanks for the tip, John.
@OffGridGarageAustralia yeah I don't think they tell you, but it's a cheat I learned years ago. Yeah just by hand lift up, feels weird but give it a few seconds and it's good to go
@@john0270 You will be my hero!
Hi Andy and thank you again for this video, it's interesting to see the evolution of some manufacturers. Yes the design is nice, but many others are doing almost the same thing now.. concerning the choice of push cells, I think only economical for them, but not sure that they will benefit the end buyer? currently there are so many of them making battery packs, that the competition is really hard!! about the automatic fire extinguisher system, for me it's a gadget, and sincerely I think it doesn't particularly give confidence!! on the contrary because the average buyer, could think? it can catch fire!
This is my opinion on this Seplos news battery pack Polo!
As usual your videos and these comments are perfect and impartial! and that is important. Thanks Andy!
Thanks for sharing your thoughts. Always appreciate and looking for your feedback.
Yeah, the fire extinguisher is more a gadget. Maybe OK for a small cable fire. But would you rely on it? Probably not.
The product is missing some important key components and is not ready for market yet.
I have mixed emotions about this battery. It looks sleek and clean for sure. Love the fire extinguisher as well! I do like that the cables can be hidden but at the same time, these batteries shouldn't be set up in sight really. I definately agree about the problems you pointed out. No switch on the front. The breaker should be on the front for emergency access as well. But I do not agree with breakers and fuses on the negative. Always kill the live wire. Ground is just a ground. Definately not the best terminal to work with either but they are more user friendly compared to those special connectors on the other batteries though. And as for the pouch cells, that is a massive NO for me. They seem to be the most unstable and prone to issues. Still love to see companies are trying different things though!! And always enjoy watching the German Aussy man!! 😁👍🍻 Thanks for keeping us all in the loop for the latest and greatest!!!👏👏👏
Great comment, thanks a lot for sharing your thoughts 👍
Switching the positive line is standard, but switching the negative line is actually more efficient and cheaper. Your choices are: (1) Switch the positive with a P-channel MOSFET, (2) Switch the negative with a N-channel MOSFET, or (3) Have a charge pump on the circuit board to generate a voltage higher than the positive, and switch the positive with a N-channel MOSFET.
P-channel MOSFETs have a higher drain-to-source resistance (Rds) than N-channel MOSFETs. That's why N-channel MOSFETs are more efficient. N-channel MOSFETs basically just work better... they have significantly better electron mobility. So, for example, high-end switching power supplies will actually use N-channel MOSFETs to switch both the high side and the low side but it takes a special circuit called a "bootstrap circuit" to make the high-side N-channel MOSFET actually work.
But you nailed the potential problem. If there is an alternative sneak path to the battery negative, switching the negative doesn't break the circuit. Sneak paths to the battery negative are a lot easier to mistakenly create than the sneak paths to the battery positive. However, fully enclosed batteries with no exposed "real" battery negative can utilize negative-side switching safely.
Yes, thanks for this explanation. Up North and Personal said the same below about the N- and P-Channel FETs.
You really need to ensure your coms cables are all isolated so there is no issues if the BMS turns off. It could cause a cable fire otherwise.
I like the case look, but that is about as far as it goes. And, you showed their pouches didn't even meet their 100ah specifications. And, you are right, the units do need On/Off switches immediately available on the front. As for the panel covers on the back, they could be left off but that would eliminate a safety factor. You identified a lot of the things that I also noticed. The Seplos Batteries look good, but I think I'll hold off from buying them for the moment. I can put other types of batteries in a rack with a door and get the same type of safety factor, be able to separate and pull whole battery with less trouble, and replace a bad cell when its needed. I buy my equipment using these characteristics...reliability, availability, maintainability, and dependability, not how good looking someone has painted their Yugo. Thanks for the review.
If their V3 BMKS would have a decent and working balancer which could handle the battery, the cells would have been top balanced and we would have reached the 100A.
I'm editing the Seplos V3 BMS video right now. That will be an interesting discussion.
Andy, I was extremely bothered by the fact that the "battery" label you put on the crane was crooked.
I feel you 😂
That was on purpose. Like a wooden sign nailed onto a wall 😂
Agree ... safety issue with the breaker access. It would be nice with a smoked plastic cover that you could lift up and have access to breakers and resets
And easy to clean for the missus if the battery is in your living room 😂
Looks really nice. The wheels are a nice touch as well.
Too bad about the poorly reachable components and reset switch, but this also has advantages when someone is cleaning or watering the plant on top.
I stopped counting the times switches on my audio setup were accidentally pressed, and even the speakers have some damage.
Cleaning live charge wires, circuit breakers and reset switches is not good. So this system also has a high WPF next to it's high WAF.
Yeah, I know what you mean. It is build in a safe way but a bit too safe in some ways.
I would not like a battery in my living area (and it is not allowed in AU anyway), so the WPF is not too important.
23:14 Those "Tesla powerwalls" look like they have Seplos branding on them.
Switching from switching the positive to switching the negative probably removed the need for a high-side n-FET driver and high-side current sense.
On the communication ports, I would think that they would be galvanically isolated - otherwise turning off the circuit breaker in one of the batteries would cause one of the wires of the RS485 cable to become a current carrying conductor, which isn't going to end well.
Looking at a post on the Victron forum, the unswitched negative requirement was for old MultiPlus-II inverters etc, where presumably the VE.Bus interface was referenced to the DC negative.
Thanks Andy 👍
Thank you, Wayne.
Very cool Andy. Huge design improvement in several areas, but having the main breaker burred behind a panel in the back of the unit rather than on the front is not my thing.
Yeah, the breaker is a big concern.
@@OffGridGarageAustralia The other concern I have with many of these systems is that if breakers with small contacts with minimal interrupting force on those contacts are rated to interrupt thousands of potential amps and won't weld closed on a major short circuit? I've seen industrial AC breakers rated at 50,000 amp interrupting capacity have one or more contacts weld closed and cause a panel fire.
Most breakers are intended for overload protection rather than short-circuit interruption, my preference is always to have a fuse for short-circuit protection, especially in something intended to be operated in a home or living space rather than a detached garage or out-building.
Some may argue that the BMS is a second safety for short-circuit, but they are solid-state switch that can fail closed rather than open under short circuit.
Last month, a neighbor asked me to inspect his expensive e-Bike that had it's wiring literally vaporize and its flame-retardant plastic battery box catch fire due to a short in a battery connector. The Bike was charging in his garage under his bedroom. The ebike Battery had built-in Battery Management System board that failed to prevent the massive short circuit, that resulted in a dangerous and catastrophic fire. That bike had a Li-Ion rather than LFP battery, and as such, my neighbor is lucky that the battery pack cells did not catch fire which could have placed his home and family at risk. Yet another example in support of my contention for fuses as a safety design element in high-current battery applications.
Thanks Andy - as always, 👍
Thanks, Dave!
At least the boxes look smaller than the giant Seplos 48280L box I've just put in the recycling shed, that thing was HUGE!
Not comparable. The MASON is 280AH, this one is only 100Ah.
@@OffGridGarageAustralia I wasn't saying they were, just joking about the sizes of the boxes all this stuff comes in 🤣
Thank you for showing us this beautiful and stylish new battery, however, like your good self, I prefer to be in charge of the accumulator in fact I have just received two Seplos BMSs and expecting 16 304Ah cells for the construction of at least one of them to start with in addition to the 100Ah already in the system. As far as the fire extinguisher I'm not worried because I will construct a large one for the solar shed also feeding directly onto some components based on what I used to build for my competition Porsches. Thanks for sharing, I must admit that it really does look the part.
Yeah, DIY is still the best option, I believe.
Hi Andy! 1) It's cheaper and simpler to disconnect the ground. You can use N-MOSFETs instead of P-MOSFETs. N are a little more efficient, but the simpler/cheaper angle is what the makers go for.
2) I bet if you jet forward 5 years most of these rack-battery systems will ALL be pouch based. I don't see much need for swapping out single cells. If the batteries are good quality none are going to need replacement until they're all swirling the drain. Besides those who are happy to over-pay for pre-built scrawny capacity rack mount batteries are not the type users to dig into a battery to do a cell replacement anyway. Here come the pouches! (yuck) Three of my 400Ahr batteries are pouch type...
Thanks, Keith. So it's about the price and cost again...
And good point about the pouch cells and pre-assembled batteries.
Now just make a version of this kit for diy with that bms for the standard cells. I would buy a few kits and source my cells.
You may want to hold on until the BMS video 😉
The New BMS Studio software (battery monitor) looks good but i was not able to connect to a v2 10E BMS. There is also a new Firmware for the v2 10E bms 16.6 but i found no documentation about the changes.
Nope, the BMS Studio is only for the V3 BMS, I'm afraid 🤷♂️
16.6 is what I always had with the V2 BMS. Was there another version before that?
@@OffGridGarageAustralia by delivery I had the 16.4
@@andreasreder9560 Maybe I have the 16.4 as well. Now that you write it here, I'm not sure...🤔
I think Seplos should put a vertical hinge on the back. I bet they'll want to keep the front plain.
Even then, the breaker is at the back.
about the backplates: by just replacing the hooks with some magnets would do the trick
As usual Andy great thoughts and initial review. Great looking battery pack, but as you point out some disappointing practical functionality issues. Strikes me as a glossy marketing package with some serious serviceability issues. Lost me at pouch cells I'm afraid.
They could never explain why they went with pouch cells🤷♂️
And the other flaws I pointed out... not so great.
I like the Jaki battery more as it ticks all the boxes.
Seplos BMS Welcome you to gardening with Andy.
Not going to happen! My wife has her greenhouse, I have my battery shed and I'm not putting geraniums in there.
I appreciate the way you highlight the positive and the negative features equally, whether it's the hardware or the software, it makes for a very informative video.
Thank You.
Thanks a lot for your kind feedback.
Could not read data of the small fire extinguisher please could you add info for this device.. or a teardown 😁TIA
It's in the description. This is all the info I have myself.
Great fire extinguisher concept, would be nice to see this as a stand alone product for wider battery community...is there a maker name underneath it?? Loved that you talked about access to breaker at bottom if stack, niggles & design issue's!
I left a link in the description where you can get one. Not sure how efficient they are though for such a battery. It's more for a small cable fire, I guess...
Isn't it about 4 times the size of a normal 100ah battery with built in bms?
No, about the same for a 48V battery.
You do a great job with your evaluations. I am still looking at setting up a solar system in the next 12 months.
Looks great, but unfortunately, the cells are not servicable. What is the expected cost of the battery shipping, etc? Does the software have a reset function in case you screw up the settings?
RS485 & CAN require an end of line 120 ohm terminator resistor. How is this set on the battery?
Is the BMS available separately?
Keep up the good work.
Thanks for your feedback and kind words.
Yeah, a lot of open questions. I will address some in one of the next videos about the BMS V3.
CAN works for me without termination. I use the 3m CAN cable from Victron and had no problems so far. If the cable length is short, I guess it is OK. The BMS definitely have a termination on-board.
Hello Andy,
is v3 BMS compatibile with 10E?
I mean, can we connect them togheter using RS485 ports? Do they communicate?
Spoiler alert, not it is not as far as I tested it. I will do a bit more testing soon but, no coms between V1/V2 and V3.
Hey @offgridgarageaustralia great review, thanks for the detail. Just my 2 cents on why pouch, I suspect pouch cells are becoming cheaper than prismatic (likely due to increased pouch cell production in China for EV batteries). Pouch cells can be packaged smaller than prismatic or cylindrical BUT it really depends on the decisions made by the design engineers.
I think i prefer every thing at the front. If you want to install this into a tight location you may not be able to get around to the back.
Needing to pull the unit forward just to turn it off?
Whilst those with all the connections on the front don't look as neat, they make me feel I would be able to check/fix etc easier than this unit.
Also I worry about having to replace the whole pack as one unit. feels wrong.
Great video as always
@davidcassidy2944 - how many instances have you seen where someone is replacing a unit?
@@bobblack3870 how many times have you needed to turn off a unit?
How many times has someone wanted to check the Comms cable is pushed in fully?
@@davidcassidy2944 You have veered off topic; I mentioned nothing about switches or cabling. Note your words are "Also I worry about having to replace ..."
in all battries and inverter the negative is switched and positive is always connected because under load the negative wire of dc current get higher temp mostly than positive. and flow of electron is from negative to positive, its my observation.
Pouch cells are a lot cheaper 😅
The APP can be used by anyone easily. So they might be afraid, that inexperianced users do mistakes.
But I think it should be public nontheless.
Always some nice supprieses and new tech at your chanel...that is sooo good!
Thanks, my friend. The app allows me to change the inverter protocol with one click and no confirmation 🤦♂️
Even while swiping up and down, I accidentally switch it to something else without noticing. A few minutes later, the Cerbo started complaining 😄
Don't the batteries have there own internal oxidizer? Will the extinguisher help?
i like the idea of the rack mount and stackable but yet no one seems to do controller inverter hybrid etc units to rack or stack with them unless you look at the portable units that stack seems a big hole in the market
Even Victron allows in the connection guide "Wiring Unlimited" switching or fusing the negative cable. You just have to do it the right way.
Some installation have a main switch and/or a main fuse in the negative line, because there is no danger touching it or make an accidential connection with the chassis or other grounded parts. The shunt is also in the negative cable and there is no special isolation necessary. There may even be a regulation that requires to have a switch in both positive and negative.
So Victron gives a recommendation, but it isn't mandatory. This may be because some people have fried the communication ports by switching only one component of a paralleled/split setup and not all of them concurrently.
But a better solution would be to use galavanic isolated communication ports. This would avoid such problems alltogether.
Regarding the whole system:
- I am a bit disappointed that it doesn't have active balancing.
- Pouch cells are probably a bit cheaper than prismatic cells.
- Failed LiFePO4 cells normally fail with high resistance. So paralleling them without fuses is no problem.
- The build doesn't seem to be fully thought through (connectors, power button, cable duct, ...)
- Connecting with a copper bar would mean addeing about 35 sqmm for each box. This will get very thick with more than a few boxes.
- To avoid unequal charging/discharging + and - connections must be placed at opposite sides.
- It has a nice appeareance, but who would but this battery into the living room. Then the Inverter and other components would have to be placed also in the living room. An they have a totally different design and noisy. This will have a very low WAF.
All in all this isn't the burner for me.
Hi Andy
It does say lithium ion on the box, they are usually pouches
Are they definitely lifepo4?
If not wait for the spontaneous combustion
Hello from brawe Ukraine! LoFePO4 its from Li Ion family.
In the Luna2000 Battery from Huawei there's also an integrated fire extinguisher, they're around since 2021. And i think you missed the fuse in the positive lead in the battery, directly in the corner.
10:50 ?
@@Meiestrixok, I missed it 😅
Maybe it got lost in buffering due to bad internet 😂
from this episode is the handworking crane i loved the most!!!!!..... your back too? ?
The crane is great. I could lift these batteries back and forward all the time. 😁
1 step forward but poor execution on obvious connection issues and agree with all Andy’s comments
Andy what do you do with all the batteries. At some point you can't possibly use all the capacity you accumulating.
I am jealous!
Do you want some?
I have some plans though...
And Andies sickness continues. A new battery, so now we will have to build a new roof so we can install more panels to charge them.
A nice looking battery, but it needs some improvement. A switch on the front for sure. As for the cells, it would be interesting to see what exactly is inside a prismatic cell. I would think it is just a hard case stuffed with a pouch cell. So by using pouch cells, it reduces the cost of these batteries.
If it's not top balanced & discharged below 2.5v then the low voltage cell & voltage drop from high current discharge will report less usable capacity. A few more charge cycles to see if the cells become better balanced. Would it help to use ~1.1A after atleast 1 cell has turned the balancing on?
👍 It looks nice, but time will tell if everything is done well.
Yes, wait for the next videos with this battery.
I like the stacking idea, but for me, the battery would have to: 1) be in a rock solid case that can take 20 years of stacking 2) lowest base with the caster wheels needs to be an industrial life type, where you can bring the wheels up when not used, so the whole thing rests on the metal base, never the wheels. Also, a wheel rubber that survives 20 years without falling apart after 7 years due to loss of softeners 3) absolutly safe. No openings, where a coin could drop into and wreck chaos etc 4) upright prismatic cells for easy maintenance and trust into the cells liquid never leaking 5) a 4A balancer without need for hacking in a neey 6) displays on each module an dproper switches 7) perfect insides, with proper cabling, warming pads for winter etc 8) 1C standard discharging with 6000+ cycles 9) small and high capacity variant, so smaller homes can also reach 200A+ 10) maybe even a HV variant, since deye now has the HV hybrid
I guess the password issues is likely down to users Vs installers. I suspect they expect the installer to set up the battery from their laptop and then the customer can just view it in the app.
Most of the time you don't want customers being able to change settings. Advanced users like yourself will be happy to change settings via a computer anyway.
Well, if that is the case, make a password for the user and a different one for the installer with elevated access. My Fronius system works like this.
As a traditional Seplos = it has potential, BUT... ,
it's not a finished development for practical use...
(I expect it will be similar for the new BMS with the new software.)
All the problematic things you listed should be improved and changed by Seplos.
It would definitely need a prismatic serviceable battery cells.
Basically, just the box itself is interesting from a visual viewpoint,
and even that would need to be changed and finished for better everyday use.
Yes, I agree. More work is needed.
The Jaki batteries seem to tick a lot more boxes...
I think you may have done seplos customers a disservice - if you have convinced them to make those Victron parameters user set rather than calculated by the BMS.
The charge voltage should be calculated and the charge current and discharge limits also should change depending on battery state.
They do change once the battery gets full or when one bank fails in a parallel setup. It will be in one of the next videos.
Hello, I watch a lot of your videos and I also use batteries with BMS SEPLOS that I assemble myself. A question: what do you recommend as a method to balance the cells when they are received and used for the first time?
Thank you for your feedback and watching my videos.
If I buy all cells from one source, I would just install them in series and connect the BMS. Charge them up and decide later if they need any balancing. Either the BMS can handle that balancing or your can temporarily install an external active balancer.
Are parallel cell pouches a potential problem? I would have thought they would be ok - essentially looking after each other. Maybe a temperature sensor on each cell if you are being paranoid is all that is required.
Note most cars have 2 pouch cells - some have 3 - some like porche have 4 pouch cells.
What happens if one is faulty?
I'm not a big fan of paralleling batteries or cells without further safety measures.
Parallel battery cells in cars have individual fusing, I believe. At least Tesla has.
I have an older LG Chem 10kw battery, can I plug one of these together and achieve 20kw
Can you try daisy chaining several brands together, will they communicate with each other?
Yes, you can operate batteries in parallel, if they have the same voltage and similar chemistry.
No, they most likely won't communicate together. RS485 is a standard (physical layer) they all use, but the protocol is different.
Im not a fan of the switch at the back, for a clean install it would most likely be close to a back wall, levelled and off the castors, which would make access to the reset and switch had to access. it wouldn't have been hard to design a recessed front switch and reset button at the design stage.
Yep, a small push button and the reset switch at the front already makes a difference.
Damn Andy, ur getting good at this!!!
Thanks a lot. Man, I'm looking forward to the time when all boxes are unpacked....
@@OffGridGarageAustralia That day isn't coming Andy, lol
@@MrHoolign Some companies may stop sending me sh!t because of these reviews 😂😂😂😂 I always tell, I'm not sales channel, I do reviews and if your product sucks, you will be in deep sh...
I'm not after the perfect battery or BMS or so, but I have provides so much feedback to Seplos and they still come out with such products which lag simple design logic (breaker at the back) and use cheap components (these terminals🤦♂). They technicians all watch my videos so they should know what the community wants. And they should ask before they build.
@@OffGridGarageAustralia 100% with ya! i more meant that you will be upgrading and designing new stuff and projects (car port?? haha) for the foreseeable future. I got a $100 that says there will never come a day where you say "There we go! All projects are done! Let's sell the tools!" lol
Love ya Andy, and thanks for the interaction, It means alot!
@@OffGridGarageAustralia and that explanation is why this community loves you man... don't ever stop the head shaking and the "Not Good" lol.... copyright that sh!t haha
After all the LG batt fires and recalls I’m not 100% happy using these yet.. they also have much shorter cycle life and prone to thermal runaway.. I do like that the size to power is much smaller thou so less weight, but as you pointed out if there was a cell that needed replacing it’s not easy and not good as renewable with lots of waste
I guess, you can take the battery apart and re-use the working cells in case one gets faulty. The question is though if they are going to do it or it goes to either landfill or recycling.
It is a bit like with welded terminals, great from one perspective but not ideal from a maintenance point. The Jaki batteries are great therefore, ticking a lot of boxes.
10 Year warranty is pretty meaningless given how much it would cost you to ship it back to China. Plus will Seplos even exist in 10 years?
You ship it back to supplier in your country derpderp simpleton.
And what is this warranty worth? Will they still have a spare battery in 10yrs time if one goes kaputt?
The password for wireless connections not made public makes perfect sence. As changes can be made wirelessly on bluetooth where wired requires access to your battery. Think someone changing settings from the road in front of your House or RV. I'm in a boat yard i see many bluetooth connection to systems around me with default passwords.
i really love watching these videos, i will be changing solar inverters soon, i am highly considering the new SMA inverter that just released since i already have a sunny boy, only down side is that they all want high voltage batteries, do you have any information or knowledge about the seplos batteries that you can run in series for high voltage?
SMA is great. They are coming from my hometown in Germany. I actually know the founders and when they started their business back in the 80s out of an garage.
I have seen the HV batteries on their website. This is nothing I can test any more because too dangerous and certainly not DIY any more.
@@OffGridGarageAustralia I agree..... I'm torn because I'm not sure of another hybrid inverter to go with, most seems to be Chinese such as EG4, and they might be great but they are all so new...
@@seanathanq as long as you get the FW updates and support...
If you're happy with the SMA, stick with them. Great company and products.
hi andy i also have 2 packs in // with it's bms3.0 i'm disappointed because i can't exceed 53.3v in load + your rs485 connecting cable why is it in the middle? on your master battery next to the victron cable? thank you for your answer andy
Thanks Patrick. It depends what RS485 adapter you have. Only their newest one (apparently) works in both RS485 ports on the back. My older one (came with the MASON box) works only with the first RS485 port. I'll explain this in the BMS video soon.
Ok thank Andy for the france 🇫🇷
Hi andy, from not sunny at all UK.
Can you help me with the seplos studio software please.
I have usb on com3 and rate of 19500 but what are the other parameters as i can't get it to work.
Can we use the new software on the older 10E BMS?
By the way, did you see my email about constant voltage charging on the 10E Seplos BMS?
Software not compatible with 10E
they are very nice looking batteries
Hi Andy, a bit off topic but I wonder if you could help me. On the JK-BMS 4S-8S edition there is the RS485 socket. I have googled RS485 to try and buy a plug to connect to this socket but cannot find the plug type for this socket. Do you know the plug type that I am looking for? Thanks.
I have read it somewhere in the DIY forum either here
diysolarforum.com/threads/rs485-to-usb-cable.47837/#post-684039
or here
diysolarforum.com/threads/hankzor-jk-bms-with-screen-and-power-button.33267/page-5#post-491377
If not, ask Up North and Personal. He knows...
@@OffGridGarageAustralia Thankyou.
All we need is a victron BMS!
or a NEEY BMS 😉
@@OffGridGarageAustralia Hmmm. For 1000 Dollar/Euro or more? Maybe they would understand what is necessary.
Hopefully the V2 of the Seplos BMS will stay available. Switching the negative is really a No Go for such systems.
All BMS do that though. The V2 is still on their website, so fingers crossed.
So far only the V1 with FW 2.8 is working, not perfect, but still workable.
I think it would be a good thing, if they put the breaker into the positive wire.
As this breaker can be triggered remotely (by the bms) there would be then a complete disconnection of both poles.
Is it veryfied that the extinguisher contains CO2 ?
I hope they don't put halon in it....
Definitely not CO2. Potassium/Strontium nitrate aerosol, a replacement for halon.
@@Doppelhorn
Thanks !
Very interesting technique.... real rocket sience :-)
Yes, the breaker belongs in the positive line!
Your wife's right! They're rather stylish cases.
Hahaha, yeah, safety concerns aside, the case is great.
Hi Andy, I'm wondering how much battery capacity you have so far in your 48volt system excluding the battery shelf
These are just test batteries which come and go being connected to the SPAT Calibration Centre.
I don't know, it probably over 100kWh.
@@OffGridGarageAustralia that's quite big capacity
@@vlapr0571 Only a bit is connected right now, but once finished, I hope to have 100kWh permanently connected for the off-grid system. I still need more solar though...
@@OffGridGarageAustralia I understand that
If you want a clean and tamper free setup, put the covers on....if you want access to terminals, breakers and reset, simply leave them off.
The first priority must ALWAYS be 100% practical functionality for every day and only then the design styling,
if the opposite is the case, as here, it is not good.
Polo are def not for me..
Like the masons for :
Use standard and servicable cells
Hate the terminals (small) and connectivity in the ( hard to reach)
App is useless
Does the bms studio work on the 10e version ?
Is v3 compatible with the 10e ?
The 2a active balancer board is a seperate purchase..
What makes that different to a 10e and a neey ?
Look forward to your tests andy, but so far i only see downgrades from my 280/10e kits
Well, I guess, I will answer all your questions in the next few videos.
The Seplos MASON is definitely TOP!
❤😂❤😂 What a great videography in the intro ❤😂❤😂
Man, it took me forever 😅
But thank you for your recognition!
I miss the noisy planner in the background!
I've got this on MP3 and will play it again in the next video 😂
@@OffGridGarageAustralia :D
Is the enclosure airtight (with a one-way-valve) to ensure the distiguisher to work properly?
Not airtight by any means. There are gaps and holes everywhere.
@OffGridGarageAustralia ... So the distinguisher is not able to suffocate the lithium flames when oxygen keeps coming in !?
@@Tom111060 I'm not expecting this tiny extinguisher to handle a battery fire at all. It may be useful for a small cable fire inside the box though. If it works.
The reason for a non public p/w for wifi, is that anyone can change your settings, where on your computer.. they would have to enter your home to get to your computer.
Well, I can just change the inverter protocol with the app without any confirmation...
Wieso sind deine schon da? Meine kommen erst nächste Woche. Wieder ein super von dir !!!!!!!
Got the boxes for 2 months sitting here already. They shipped it in March to me, I think...
@@OffGridGarageAustralia yeah cool, i only ordered mine in may, it might be faster to you than to us, keep it up mega cool channel helped me a lot when setting up my memory with the seplos bms
@@HolzMichaelEifel Took like 2.5months from when they shipped it to arrive in Sydney. Then another 3 weeks for custom clearance.
Lol, Battery crane.
Question, do you have a good suplyer for lifepo4 280 - 320 AH cells ? Thank you
I have some linke on my website which are linked under each of my videos.
I love your videos!
But there is no such thing as “negative 10” when talking about temperature.
Celsius at least... but you're right.
It seems like its not serviceable. and it looks like the stack will be limited in current based on the size of the last terminal. which kind of limits it maybe... unless you break out leads from each which kind of negates the safety benefit i think. Or maybe im just stuck in the past :)
I recommend to buy wind turbine to use the wind to charge your batteries . I wish to you the best luck
OK, will do. Thanks.
Please, please, test the fire extinguisher......get local cfs on standby in the interests of science. I had an early version of byd bbox battery that failed. So I took it to my farm and put a .223 round through it. It swelled and burped but never caught on fire even with a bullet in it
Probably not, sorry...
Not intentionally, at least 🙃
negative pole on a battery is where there is a source of excess electrons, the positive is electron deficient
Not sure if the CO² does any good if the cells really burn. The exothermic reaction will release oxygen from the P-O bond which can fuel the fire without any external oxygen. This is not as pronounced as in NMC cells where the Co-O bond breaks more easily, but this fire extinguisher might not be more than a gimmick.
The decomposition temperature of LiFePO4 sits around 600C if I remember correctly. You'd need one heck of a reaction to make this sustained in a battery like this - which is why LiFePO4 does not typically suffer from thermal runaway like e.g. with NMC unless an additional heat source is introduced.
@@upnorthandpersonal True. Which makes the fire extinguisher even more of a gimmick.
@@keyem4504 The one reason I can think of is that a spark could potentially set venting electrolyte on fire. In that case, the CO2 extinguisher would be useful . I've seen some people have cells vent, and these pouch cells likely vent faster than a prismatic in case something goes very wrong.
@upnorthandpersonal
I would bet, the pouch cells are of non vent type and designed to balloon as most pouch cells do.
It is a bit questionable but the CO2 would at least stop any auxiliary fire from circuit board, components, plastic, and wiring, so in that regard it might be reasonable. But it won't stop the batteries themselves. Stil, a LFP cell just doesn't runaway for very long so if nothing else catches fire or is put out by the CO2, it is all good.
I assume that the fire extinguisher won’t work well. If you have a thermal runaway of this type of cells, you don’t have a big problem with oxygen, but a problem with thermal capacity. So you have to use a extinguisher component which is capable to dissipate the generated heat for hours. Just a shot of CO2 will not do much. Just my 2 cents …
LiFePO4 generally does not suffer from thermal runaway: you have to introduce an additional heat source to make it happen. Just puncturing a cell, or whatever, does not cause thermal runaway, even if the venting electrolyte can be set aflame with an additional spark. This is likely why the extinguisher is there. If these were NMC, it definitely would be useless, since that chemistry does experience thermal runaway easily, and no CO2 extinguisher can do anything about that.
It is not CO² based, see my reply above.
I am impressed with the clean look, but I am disappointed with the functionality of the new packaging.
1. They definitely need an On/Off switch on the front.
2. The circuit breaker location is completely useless. Not only is it difficult to get to in the event of an emergency due to the panel covering the back, once the battery is positioned against the wall and the casters are locked down, how the hell do you get at the back in the event you need to get to the CB.
Maybe a better location would be on the side. It would not detract from the appearance/presentation.
3. The design allows the use of a busbar to join the batteries, but a M6 screw and such a narrow terminal, it will make it difficult to use a busbar that will carry the combined current of all the batteries, particularly if you are using 3 or more batteries.
4. The specification says the charge temperature is 0 -> 40 degrees C. Considering that charging will occur during the day when it is likely that temperatures could exceed 40 degrees C. If you consider that the temperatures being experienced around the world have exceeded 40 degrees in many locations and it has also been predicted that in Australia we may also experience these high temperatures, how will these batteries deal with these high temperatures?
Thanks for your email and comment Chris. Great points!
I didn't see the temp settings for charging the battery. I have reached 40° in my battery shelf last year.
i wasn't expecting such intense jacking so soon in the video
Uhhh, this jack... man... I'll keep pumping 💪
i think the back panels would be better if magnets held them in place
Great idea!
They should hire you as advisor so the software would be good from the very moment they publish it.
If they would listen to me, they would have the perfect BMS and would be market leaders. But they don't. I think it's a Chinese thing.