Brilliant! I came here thinking I could avoid a BMS, but now you made it clear I need one (and entertaining at the same time)! I'm subscribing.

@OffGridGarageAustralia

3 жыл бұрын

Thank you so much!

@roberthill4239

2 ай бұрын

You can avoid a bms

This is a great explaination especially to the begginner showing generally how a BMS works and why a BMS is important. It doesn't tackle the current limitations and temperature cutoff stuff so hopefully you can make a more advanced video tackling sizing a BMS and explain the other functions. Great content, sir.

@OffGridGarageAustralia

3 жыл бұрын

Thanks, I will show more of these BMS bowel once we set one up. But, yeah, there is more to it, than just balancing and voltage protection.

What an excellent explanation and demonstration of the function of a BMS. Thanks Andy.

@OffGridGarageAustralia

3 жыл бұрын

Thanks Ben ☺️

Thank you, Thank you, Thank you!!! This was the best (and funniest) explanation I have heard on the BMS. You have a great way of teaching.

I am still on the fence about a BMS and in the end I bought a 100amp BMS with a Bluetooth module. (24v system, 100AH LIFEPO4). The application displays the individual cell voltage and pretty much all parameters can be changed. In the end I decided for a BMS because of the low voltage cut-off since the inverter is not connected to the solar load controller. It also does cell balancing (only 2amps so it might take a while for a 280ah cell, haha) so that is a bonus. It handles 60amps draw for about 45 mins without a problem but we'll have to see in the long run if it keeps operating. So far I am really impressed with it. And the phone app is kinda nice.

@OffGridGarageAustralia

3 жыл бұрын

Great feedback, Peter. A BMS is a must! There is no way to keep these cells in balance without one. 2A balance current is a lot. Mine has only 250mA, I believe.

One of the better explanations of how/why a bms is needed, I would also imagine some capacity is lost when one cell gets to the maximum voltage and all the rest are somewhere below and in a large bank this could add up to a noticeable amount.

sh*t can happen no matter how careful you are, so just use BMS. Ur battery are expensive

@martintokinaga5261

3 жыл бұрын

This is exactly what he is saying at the end of the clip. Obviously you have not watched to the end.

@user-ix4uy2ld4f

Жыл бұрын

需要我的喇叭吗

Thanks, Andy. This video was very clear about how a BMS works. You just topped up my knowledge. Have a nice day.

@OffGridGarageAustralia

2 жыл бұрын

Thanks, you too!

i really HATE clickbaits....but this one got a thumbs up for being the most instructive one😊

@OffGridGarageAustralia

2 жыл бұрын

Hahaha, thanks Alex. It's not real clickbait, right?

A brilliant way to explain the importance of a BMS. Thank you.

@OffGridGarageAustralia

3 жыл бұрын

You are welcome!

Always learn more when I watch your videos! Thanks, J

You are wonderful. I am learning from your experience. Keep on. Greetings from Saudi Arabia.

@OffGridGarageAustralia

3 жыл бұрын

Thank you for your feedback!

Excellent video, thank you for answering my questions!!!! 💪😉👍

@OffGridGarageAustralia

3 жыл бұрын

Happy to help! Thank you.

What a great lesson. Thanks.

Great explanation! You can also top or bottom balance the cells as well. For using with off grid solar , most are now recommending top balancing. You can take your cells (In parallel) connect a DC Power Supply Variable 30V 10A to the bank and take them all up to 3.65v. Disconnect the cells and put them back in series and your done! Will Prowse has a great video on doing just this. Thanks for sharing!

@OffGridGarageAustralia

3 жыл бұрын

Thank Dan. The pack is balancing for the last 4 days already. It takes a while with the small DC buck converter I'm using...

@CollinBaillie

2 жыл бұрын

I think the purpose of top/bottom balancing is to get the cells prepared to be installed into a pack. It's a starting point only. The idea (of top/bottom balancing, and NOT using a BMS) is to rely on the cells kind of bouncing around between the min and max voltage of the weakest cells, without using a BMS. But this is flawed long term, because cell properties will change over time, and you don't want to have an outage of your system while you top/bottom balance again. Doing a top/bottom balance at the beginning and then building your pack with a BMS, will give the BMS the best chance of doing it's job. If you introduce an additional active balancer into the mix, this will enhance the BMS by keeping cells balanced from each other, not just burning power into heat to lower the high cells. This gives you the maximum power out of the pack, but it will cost the most.

There is a better solution to the unbalanced pack. Use an active balancer equalizer capacitors board which take charge from the highest cell and dump it in the lowest cell. It will keep them within 5mv. The solar charger control the charge and the inverter control the discharge. If you want more energy from the sun in cloudy days use solar panels in series with 150v capable mppt chargers.

@BenMitro

3 жыл бұрын

Are you sure about the active balancer claim - can you point us to specifications that show this feature of active balancers vs non active BMS? Personally, your comment and others making other ludicrous claims for active balancers reek of marketing hype.

@NightsReign

3 жыл бұрын

@@BenMitro While I have no way of knowing whether the OP was acting in good faith, I do distinctly remember Julian Ilett having a few videos on active balancers as opposed to passive/bottom/top balancers, to balance his supercap/ultracap banks. The ones I saw _I believe_ were roughly 6 months-1 year ago. Also vaguely remember a few videos on DIY Arduino projects accomplishing the same task, utilizing Digital-Analog Converters, for battery banks far in excess of typical series counts. I'm not certain whether he was part of those as well, or in misremembering other KZreadrs. You know, I should probably examine this subject personally, if only to be more accurate regarding this topic in the future.

@BenMitro

3 жыл бұрын

@@NightsReign Thanks NightsReign - I did watch Julian's coverage of active balancing, and I really like the idea of active balancing, but from what I've seen, power savings, and super accurate balancing are not founded in practical reality. I mean many BMS balance at 30 or 100mA - and for a short stretch of time to adapt the cell to that of the pack, now a quick and dirty, order of magnitude calculation tells me that to discharge say 100mV at 100mA amounts to 1mW and that may be for, I don't know, an hour? of the total charge time of the cell. With a 100AH cell, at 3.2V having 320Wh, to quibble over saving 1mWh sounds, like I mentioned, marketing hype rather than practical advice. This OP's comment sounded like active balancers are more precise "5mV" - what??? I don't normally react much to gibberish in comments, but this and other comments in this video really got under my skin. Again, thanks for responding, its great to discuss stuff with other commenter like yourself. When I'm wrong, I find out about it pretty quick and I do attempt to right my own wrongs (and there are many things I misunderstand or simply don't understand).

@andycanfixit

3 жыл бұрын

@@BenMitro The other issue with only using an active balancer instead of a bms is that it lacks all the other safety features a proper bms provides, such as over charging, over discharging, over or under temperatures, too much charging current, too much discharging current, etc. If the balancer fails you'll only know if you have some other system monitoring it, if your charger fails and puts out too much voltage you'll only know when your pack fails, generally if your bms fails it simply disconnects the pack so long as its a decent quality one. So while an active balancer might help when used with a bms to handle larger swings in voltage than the BMS can do itself, it's just not a good solution all by itself because it leaves multiple ways for the batteries to be damaged.

@neliosamch3195

3 жыл бұрын

@@BenMitroif I were not sure, I'll not be guiding people in the wrong direction. This one is 2A but for one of my 280ah 48v pack I am using 10A balancer to bring the pack within 5mv. kzread.info/dash/bejne/pIWbscetZ6SuYKw.html. And of course these balancers aren't long lasting as BMS but you can get more power out of the pack. As for charging I use several makeskyblue which I can adjust my top voltage to 54v and the inverters cut off point is adjusted to 48v for the bottom limit.

Bottom balancing will result in a ragged end voltage and a balanced discharged voltage. Usually the ragged charged voltage is not a terrible difference but when you remove the charge it will bleed off the top and usually be quite balanced at fully charge resting voltage. Takes a bit to bleed off the charge voltage to a stable resting voltage. Usually around 3.35 volts.

@onegreenev

3 жыл бұрын

That cell that is filling faster is your low capacity cell in the bunch. If you charge to 3.5 volts and your low cell goes to 3.65 your pack is fine and let the charge bleed off to static voltage and I bet you will see 3.35 or maybe 3.4 volts per cell. So all have the same capacity at this point and will all be equally balanced at the bottom if you don't let it go below 2.5 volts. Monitoring the voltages is fine. If you have a cell that reaches 3.65 volts long before the others and there is still a bit of time before your termination voltage is reached and if that difference puts that one cell above like 3.8 volts then you need to swap in a better battery that has a similar capacity if you want to go BMS free.

Thanks so very much for the details and explaining the BMS.

Very good informative video that easily explains why you need a BMS and how it works. Well done and thank you.

When I finally got to your sick sense of humor, I couldnt help but laugh!

@OffGridGarageAustralia

3 жыл бұрын

😂 got you, ey?

Awesome||| thank you for the simple easy to understand explanation. I like how you used the lights as a load to explain what the bms does internally.

@bobbygunn2393

2 жыл бұрын

By the way I like the phrase “what the frog”

@OffGridGarageAustralia

2 жыл бұрын

Thanks a lot for your feedback, Bobby. Much appreciated.

Thank you every good information

Excellent demonstration and explanation, thank you so much

On your cellmeter, push cell and mode button together and it's supposed to balance them. Not a BMS replacement but usefull anyway. Thank you, sir.

Excellent video sir, many thanks for that information!

@OffGridGarageAustralia

3 жыл бұрын

Glad it was helpful!

Great video. Thankyou so much.

I love this video! Human BMS I love it. It shows you exactly why you should use a BMS unless you want to do all that unnessary manual work but it is an excellent way to teach BMS tech.

Well done, helped me understand easily.

Thank you very much. This is what I needed to know.

@OffGridGarageAustralia

3 жыл бұрын

You are welcome!

Lol, great vid man! That cell checker if you hold down the right button it will go into balancer mode if you want to balance them while charging. Pretty handy cheap device. Another option out there if you want to get it to work a little more efficiently is to get an active balancer they take the voltage on the high cell and transfer it to the low cell instead of wasting the energy using a load resistor. Fairly cheap the only caveat is you need to have your own low voltage shutoff. I prefer a regular BMS with my smaller battery banks but as you go bigger the BMS can't handle the amperage. So options with a larger bank are to use a regular BMS and have it control a relay using the output wires. My setup I went with an active cell balancer and a low-voltage cut-off relay, Lots of options out there got to choose what works best for you.

@OffGridGarageAustralia

3 жыл бұрын

Thanks for the feedback. If I hold down the right button it goes into discharge mode...

@NightsReign

3 жыл бұрын

@@OffGridGarageAustralia I wonder if it's simply a difference of models from the same manufacturer, or they mistook yours as an altogether different device?

@AQUATICSLIVE

3 жыл бұрын

Sorry yes different than mine. They look the similar but mine is a 5-in-1 Cell Meter. Made by Tenergy.

Learned a lot by from this video! Thanks. Keep it up

@OffGridGarageAustralia

2 жыл бұрын

Thank you!

Absolutely need a BMS :) For over-charge, over-discharge, and temp (hi/low) protection to cut-out a load. Balance as a feature of the BMS is good as well but not as important as the basic protections of a BMS.

@OffGridGarageAustralia

3 жыл бұрын

Yes, I absolutely agree.

I am 77 years old and have lots of experience with battery systems. always use series connection. never parallel. if you need more capacity make the cells higher capacity. where I retired we had 2 radio back up banks of 400 ah. 6 cells in series. they still met spec at 22 years old. no BMS at all. If you add a 2nd battery to your vehicle to run your ham stuff etc. add a circuit breaker in series with a N.O. relay that comes on with IGN(NOT ACC) so when the engine is running both batteries charge properly and when parked the 2nd battery can get run down but your vehicle will still start. NEVER use a battery charging splitter. the splitter causes both batteries to be undercharged and lots of trouble with that.

Great video! Love the dry humor!

Another great video thank you for all the work you put into this chanel

@OffGridGarageAustralia

3 жыл бұрын

Thanks a lot, John!

funny start... nice and informative vid (specially the $11 part and the frogs ":o)) ... thank you.

Without you Andy. I would be lost. CHEERS MY UNMET FRIEND!

When you have only a 4 cell battery pack, it is easy to charging the cells individually, at your desired voltage and current to recharge them up again!! I first charge mine, as' a full battery, till almost reaches its limits, then finish off, just charging the individual cells to their full potential, thus keeping the cells balanced and ready for a further discharge. Regards George.

Thanks, you good teacher, for me. Million thanks

@OffGridGarageAustralia

3 жыл бұрын

You are welcome!

Great man, good explain. Thanks.

@OffGridGarageAustralia

3 жыл бұрын

Glad it was helpful!

Got a new job position today as a "Battery Management System Operator"!

@OffGridGarageAustralia

2 жыл бұрын

Hahaha, welcome to the team then 😁

Just found your video. Fantastic explanation thankyou.

We have wall to wall sunshine today perfect for test, but temp will be about 30C

Thanks you, brilliant explanation for a BMS.

Hey thanks you've got me on me guard now

This is the best and the funniest video I've seen today lol thanks a lot for the info.

Just ordered four cells off your link. Hope I get the same capacity tests as you did. Thanks for your vids.

@OffGridGarageAustralia

3 жыл бұрын

Thank you :)

@vtorsi610

3 жыл бұрын

@Dr SpaceMan - Are you Off-Grid ?

@nubbynubs123

3 жыл бұрын

@@vtorsi610 Nah I wish. Intend on using the pack to replace 3x200ah AGM batteries in a camper van.

This is EXACTLY WHY a BMS was created.

the best controller/bms i have found for lifepro4 is electrodacus as it monitors the single cells

hi.... very clear "how to and why" video.. thank you!!!

@OffGridGarageAustralia

3 жыл бұрын

You're welcome!

Great video, the biggest issue I have is that most BMS devices have very limited current capabilities to discharge a cell and when you have high capacity cells like you show here (maybe 240Ah) they can struggle to bleed off the charge.

@OffGridGarageAustralia

3 жыл бұрын

I thought the same but it's all about finding the right settings and over time even a small discharge and balancing will work. My BMS does only 0.2A balancing and it can balance all 16 280Ah cells down to 1-3mV deviation.

Great job explaining BMS technology

I don’t run a bms myself but I only run 20-80%(mainly 60-80)of the battery. I topped balance and haven’t had any drift after 1 year so far(still 10mv). I’m running 18x 8s2p 70ah 24v bmw lithium batts. I would need 18 bms to correctly wire them up...no thanks lol. My Victron inventors and solar charger only charge up to 32v and my batteries need 33.6v for max charge. This means I will never be able to over charge. I check once a week with multimeter and thermal for hot spots once a month. You need to top balance with them all in parallel up to 3.65v then wire in series and charge max to 3.4v like you did. This will extend the life of your batts too.

@NightsReign

3 жыл бұрын

It could be confirmation bias for me, but I've noticed that bottom balancing in parallel before charging to the top balancing voltage, helps optimize things somewhat, so the cells more accurately mirror the characteristics of each other once being reconfigured to series. Depending on your level of OCD and how important the project is, intermittently pausing the charge to allow time to rest, applying a load briefly, possibly repeating a rest interval, then resuming charging can yield dividends. My unmedicated ADHD and autism, among other neurodivergent issues mean I've gotta fully disengage whenever I can't remain hands-on, since allowing myself any opportunity to botch an experiment by overlooking something important will forever be my undoing... I don't have any firsthand experience with LiFePO4 chemistry, _but_ NiCd, NiMH, Li-Ion (cylinder/prismatic/pouch cells), LiPo, and Pb, seemed to have followed this trend for me in the past. From what I can deduce, when the paralleled cells are fully discharged, then allowed adequate recovery time before charging to full, the pesky tenancy of the top performing cells quiescently trickling a handful of nA to the rest of the pack...for seemingly *YEARS* _(or at least until your perfectionism melts your mind in aggravation),_ that issue appears essentially absent. I'm very curious though, what was the impetus for your settling on 32V inverters and such? It struck me as an arbitrarily peculiar voltage which I haven't seen much in the past. Is that maximum output voltage from your PV system?

@OffGridGarageAustralia

3 жыл бұрын

Yes, that is absolutely correct, just 5 steps ahead ;) 3.4V would be my preferred voltage for these cells. I'm not expecting the balancer of the BMS will actually ever kick in with such a 'low' voltage. You could run such a Cellmeter8 for your pack too. Just be aware it sucks its energy from cell #1 and #2.

@vtorsi610

3 жыл бұрын

@@OffGridGarageAustralia No, *NOT* absolutely correct ... If he charges an 8S battery pack to 32 Volts, he certainly can OVER-CHARGE one cell while under charging the other 7 cells. Charging to only 32 Volts does *NOT* prevent over-charging of any one cell. Checking your cells "once per week" does not prevent a problem from occurring while you are asleep or while you are away from your home ...

sorry sir, if there is a weak cell in the row it will be the first which reaches the max. voltage and will also be the first which is at the lowest value decharging the battery. Only cutting off the process will help to rescue the weak cell not balancing.

Waiting patiently for the comments saying "NO YOU'RE WRONG YOU ABSOLUTELY NEED A BMS!!!!"...

@OffGridGarageAustralia

3 жыл бұрын

Hahaha, unless you want this job, right?!

@upnorthandpersonal

3 жыл бұрын

People just reading the title and jumping to conclusions? No way! /s

@upnorthandpersonal

3 жыл бұрын

@DIY Projects I also have had systems in the past without a 'real' BMS, only an active balancer. You can get away with it when you know what you're doing. I still prefer to build systems with a BMS - things can always go wrong no matter how good you think you manage your cells. I'd rather have an additional layer of safety, and since you can get a decent BMS at low cost I don't see a reason why not to.

@fernandodambros4693

3 жыл бұрын

BMS operator 🤣🤣🤣🤣

Love your videos and even more love your off grid garage! Question, how can you test a battery pack managed by a BMS that does not have an app? or how do you know if the cheap BMS actually do anything? The ones with the apps are way too expensive to use on small 12v packs, fine on a large system but small individual systems makes things uneconomical.

Probably the most significant content. This video should be modernized or at least remastered and re released again. Excellent! Now tell us more about paralleling cells und one series bus voltage please. ✌️♥️👍

BATTERY MANAGEMENT SYSTEM OPERATOR nice one sir.

Very clear explanation

You don't need a BMS if you use a separate DC-DC buck converter for each cell only for charging. The advantage of this is you don't need to balance each cell, they will be always charged to the voltage set in converter.

@OffGridGarageAustralia

2 жыл бұрын

Yes, you can charge each cell individually with it's own 'charger'. But you should not connect these converters all to the same power source 🔥

what a cool video! Cheers

@OffGridGarageAustralia

2 жыл бұрын

Thank you, Jonathan!

Wow Great idea thanks

So true, a BMS is necessary. However people should be very wary that not all BMS's do the Balancing feature. Some will just disconnect the cell if it goes outside its parameters. Separate Balancer/Equaliser boards are available to add onto battery packs with a BMS not including this feature.

Brilliant! Thanks Andy. Could you perhaps recommend such a solution for lead acid stationary batteries ? as in connected to a UPS?

Great advice. The bms operators job though, I tried that but I quit lol

@BenMitro

3 жыл бұрын

Keep the economy going...you can probably get jobkeeper payments when the batteries are all balanced.

Greetings from Sweden. Great Chanel 👍👍

@OffGridGarageAustralia

3 жыл бұрын

Thanks and welcome

@zarbonida

3 жыл бұрын

@DIY Projects you have to come in South of Europe. I live in Sicily island and with a 5.4kW PV, yesterday (04 january 2021) it made 16kWh

@JPHER217

3 жыл бұрын

@DIY Projects Yeah only sustainable during winter months would be hydrogen during winter from solar panels on summer, but expensive.

Perfect Explanation 👍

It would be interesting if you could do a comparison with two identical panels out in Open Sky both on sunny and cloudy days one with an mppt charge controller and the other one directly connected to the battery and measure how many kilowatt hours each system produces.

You could always keep the 3.6V bank in parallel and use some kind of inverter to generate the 13.6V to 48V you need for your purpose.

@OffGridGarageAustralia

3 жыл бұрын

Uhm, probably not, the currents would be BIG. I mean really big!!!

@TimHayward

2 жыл бұрын

But the distances could be very short. I think I may go this route.

Thank You Andy for showing us this cell meter 8. Its would be nice to have a independent control monitor beside the BMS, ideal for people like me who suffer from cell phone allergies ; )

@OffGridGarageAustralia

7 ай бұрын

Some BMS now come with a display where you can check on the voltages of all cells...

@topeye4202

7 ай бұрын

@@OffGridGarageAustralia Thank you, yes there are "overwhelming fancy looking" displays for my Jikong BMS, but they cost 6AUD more and they are less convenient to operate. The Cellmeter8 costs less than 10AUD here on Lazada. It fits perfect for my 24V battery and I get some redundancy this way for more security : )

you got me there. position of BMS Operator taken :D

17.7 min waisted that I will never get back! Thanks buddy!

Hahaha conclusion kinda took me by surprise, but made sense 👌 subbed

@OffGridGarageAustralia

Жыл бұрын

Thanks a lot and welcome on board. Just to explain how a balancer works, right?! 😉

thanks for the video, nice and clear. And I like the frog.

@OffGridGarageAustralia

3 жыл бұрын

Thanks for watching!

I’ve been running my 4s Calb 180ah cells without bms for over 3 years. Top balanced once at the start and they are still within .02 v of each other

@OffGridGarageAustralia

2 жыл бұрын

Wow, that's great. And brave. How often do you check them and I guess you use them right in the middle of the curve before they hit any steep sections?

@A2an

2 жыл бұрын

​@@OffGridGarageAustralia Hi It is with a lot of respect to you and not least the time you use on all the videos 👍 Nop... That is wrong, if you will run without BMS you need to bottom balancing all cells. You need to drain all the battery down to 2,75? V (down to the knee wher there is no energy pr. milli volt), get the last digit so close as possible on all cells and at same temperature. Measure one week later, if the difference is to high repeat the process until it is right, then you NEVER have to doo that again I have a battery pack 42 Cells from 2012 (Thunder Sky Cells 160 Ah) and it is running just fine, last checkup 1 week ago and all is just fine. So yes I check the cells now and then 1 - 3 yeas apart. It is used in my car and is charged at least once a week. Cell Voltage 3,65 - 2,95 (Charging current 50A. Regenerate breaking 150 A.) Maximum Discharge current 350 A It is imperative that the cells are bottom balanced, since you don't know the capacity of the cells. If you drain a top balance pack down to say 2,95 you might have a problem since the cell with the lowest capacity might be wrongly polarized and the cell is Dead. My cells variator about 15 Ah. If you or anyone wish to know more about bottom balancing, search for "jack rickard evtv" it is an olde video and unfortunately Jack is Dead. If you want to know more about lithium cels behavior and how much the drift search for "Professor Jeff Dahn (Dalhousie University") runingtim 1.13.30 This video will help almost any one to understand more about LiFePo4 cells. Enjoy the videos they are worthwhile !!!

You have so many trees for poly or mono solar panels. Try thin film solar panels for power in all types of conditions, even partial shading

Great video. BMSO... "Full time job as a Battery Management System Operator..." I laughed at that. Definitely you need a BMS, specially if you are a begginer like me. It just makes your life easier and protects your investment. I already have expensive hobbies with my old vw's. After seeing your videos (and many others before yours) I decided to get a set of 4 __50 ah lifepo4 cells, and received my 60 ah BMS yesterday. Watching everything closely here not to make expensive mistakes. Nevertheless I worry about crimping quality. Not a professional by any means, but want to go solar as soon as I can. Thanks Andy.

@OffGridGarageAustralia

3 жыл бұрын

Thanks for the feedback and great comment. the 4s/50Ah battery you're building is a good start and perfect to measure and learn. Sometimes, I'm a bit scared of the 16S battery as I never have built one before.

@ricardomarcelino8388

3 жыл бұрын

I also have seen the possibility to get 280ah cells, and they are a lot cheaper ah/euro (less than half the price). Nevertheless I really am scared of such a big amount of energy and cost to make a mistake. Apart from that I will be able to do a small portable battery for camping and whatever I feel it serves the purpose, and join my portable solar panel equipment (200W). From there I will upscale my project for my house in the future, making my solar system a bit bigger everytime. So I hope to learn from your mistakes ,😁😁😁...

Ha ha ha a full-time job of "Battery Management System Operator" - excellent punch-line! Nice explanation - 10/10 !!!!

@OffGridGarageAustralia

2 жыл бұрын

Thank you 😁

With your humanity glowing through the lens, gives hope to the world 🌎

Colorado gets more sun than Florida the sunshine state . 300 plus days a year . Building my solar and battery bank always upgrading

...beste Erklärung die ich gehört habe. Danke

I'm using 12V Lifepo4 7Ah batteries that are designed for use in a UPS. They have built-in BMS which keeps the cells balanced and also provide over, under and short circuit protection! I have them wired up in series for 48V which also needed some sort of balancing so what I did was to use an MPPT charge controller for each 12V battery, that way each battery pack will be charged separately as the charge controller is adjustable for the maximum voltage! I have tried the same thing with 18650 lithium ion batteries in series, I have been charging them to 4.2V each at the same time, some stop charging earlier and some later but they never go over and they are automatically balanced! Not sure if you understand what I have done, picture it as a series of car batteries, now take a few 240V car battery chargers and connect one charger to each battery and turn on all the chargers! They might be all in series but because they are being charged individually, they will always be in balance and you never have to check on them. The MPPT charge controller that I'm using is from eBay, it's just a circuit board with no enclosure! I think that they cost $10AU with $5 shipping, they are rated for 100W so for me that means a total of 400W of charging, they can also be paralleled for twice the current output and they have a potentiometer to tune it exactly to the solar panel that you are using for maximum power point tracking! And they track extremely fast! I have had others where I would wonder what they were doing because they were so slow! You see the sunshine come out and it's like it's thinking about what it's doing! No so with this little thing! As soon as there's ambient light first thing in the morning, it's already on and trying to charge... Higher voltage is so much more efficient, with the 48V system, I just had to use 4 12V Led Down lights per room which meant that I didn't have to use thick cables to carry the current to the lights... And because my batteries are small and in their standard UPS style case, they are cheap if I need to get more storage capacity! They cost $70AU each as opposed to $500 each if I chose to go with higher capacity from the beginning! And because I'm using multiple smaller batteries, I can charge and discharge at higher current without causing them to heat up and becoming damaged so basically if I could get away with just four $500 batteries to cover everything that I need, I would prefer to get 8 at half the size, you can charge them twice as fast...

Love it!

@OffGridGarageAustralia

3 жыл бұрын

Thanks!!

Great video! Thanks for taking the time. - What size BMS do you need?

@OffGridGarageAustralia

3 жыл бұрын

Thank you. I'm going with a 200A BMS. It all depends what kind of load you will have...

@peterrock2838

3 жыл бұрын

@@OffGridGarageAustralia One of my inverters is 3000W and without the inrush I would imagine I would need a 250A BMS... You think?

@vtorsi610

3 жыл бұрын

@@peterrock2838 You tell us ... a) 12 volt or 24 volt or 48 volt system? b) Max amps rating of the Inverter, Charge Controller and Battery Bank?

Me personally I would rather use a balance charger than to use a bms l. Then have a cell monitor with a buzzer alarm when a particular cells drops to say 2.7 volts.

@OffGridGarageAustralia

2 жыл бұрын

Most likely I'm not home if the battery is fully charged or discharged. A buzzer will not work in this case. You always want a BMS for your battery to protect it.

i was thinking that the best connnection for batteries is in packs of four , a parallel of two in series . and that forms a block , for a scale up, next you go to four blocks . the reason behind this is to keep a uniform charge and discharge of the batteries ,without a single battery or more ,goes between two other batteries . and i think the measuring points for calculating where an error in the uniformity exists , are less .

Couldn't find "Preferred Lightbulb Setup" anywhere on the website. Any chance to see a future video on this wonderful idea?

@neliosamch3195

3 жыл бұрын

Resistors are better but it burn out energy, use capacitors instead and transfer the energy to other cells.

@OffGridGarageAustralia

3 жыл бұрын

I think I've shown it here: kzread.info/dash/bejne/dIaBsJKJYsqpp7Q.html

Lucky me, I bought the same bms. For 75 euro. Now I can watch your entertaining tutorial and not have to figure out the kinks.

Such an informative video thank you! One question though, with a BMS would you still need to top/bottom balance or does the BMS handle that?

@OffGridGarageAustralia

3 жыл бұрын

You do a top balance once and then the BMS will take care of the balancing in the future.

BMS is very important

Hello from America another great video Andy thank you what BMS are you using and what BMS would you recommend I need Bluetooth fully programmable and at least 300 amps for 4s 310 amp cells thank you for sharing your ideas and time with us keep up the good work and stay safe

I think that no BMS is not a good idea. The batteries are too expensive. Have at least a watchdog running to disconnect in case things get out of hand. There are many cheap ways to do this. Even with an arduino and a couple of mux shields. Check the voltage of one cell every second. Sound a warning if things worsen. Disconnect the battery pack if things get really bad. You don't need to do any balancing usually. Just accept that the lowest cell capacity dictates end of charge/discharge. Return the worst cell to the vendor, if it is out of spec and get a new one. Or add a little 18650 to that cell (fused!), to add to that individual cells capacity.

Thank You for posting very useful information, and this leads to my power question on this subject. When I bring in a solar panel charge controller, how do I assure that the power controller is controlled by the BMS and the BMS dominates the charging process.

nice! thanks!

@OffGridGarageAustralia

2 жыл бұрын

Thanks!

Love this video. 😆

@RichADio

3 жыл бұрын

Redundancies are important.

@OffGridGarageAustralia

3 жыл бұрын

Thank you! 😁

I like the way your garage/shed is set up. Does it get hot inside in summer? Plush, what does BSA stand for, Boy Scouts of America?

@OffGridGarageAustralia

2 жыл бұрын

The heat is much better since I covered the whole garage i solar panels. It can get up to 35° in summer inside the garage for a few hours though but cools down during the night again. BSA?

You can use an active balancer to avoid cell drifts... I do it so an it works perfect.

@vtorsi610

3 жыл бұрын

Post a URL link and price of your Active Balancer ...

Hello, the cell meter you showed in the video is in clause 8. but the balanced discharge part I guess is not active or I could not understand exactly how it works. Is it possible to shoot a video about this product? thanks.

hilarious end , where can I apply for that position ?

Another thing to consider is temperature. The fact that the outside cells will be a couple of degrees warmer or colder will affect individual charging efficiency. Subtle but will over time lead to an imbalance.

@OffGridGarageAustralia

3 жыл бұрын

I've got this battery in use for 6 months now and could never even measure a temperature increase while charging or discharging (max 60A discharge). But yeah, you're right, this could affect imbalance as well.