Battery Management System Or BMS?

[@GrizzySC]

Sorry i know this is a very old video but we use those "lipo alarms" in rc and leave them on while running the truck/car so we can hear the buzzer go off when we hit low voltage. Alot of new speed controllers for rc habe adapted lipo cutoff. Also alot of the rc branded lipo voltage check guages that connect to ballance leads also offer ballancing built in now too. Mine will ballance up to 6s and fits in my pocket. Great videos! Im just getting into ebikes and 4 wheeled electric ride ons. You knowledge is invaluable for a newbie

[@rubenb.molina6968]

Agreed. A BMS is not required on most systems. I think a BMS is more of a simple solution for those who don't want to deal with more complicated cirtcuits. Yet, If you want to squeeze the most out of your cell's life, a custom monitoring system is the best way to go. You can go really creative with an ABMS (Advanced Battery Management System - and yes, I just made that up), which monitors your batteries every so often, controls your chargers, and alerts you when a cell is showing sings of struggle.

[@michaellees-smith1231]

Ruben B. Molina i

[@alanbrown397]

For experimental use a management system isn't necessary - the point being that you more-or-less know the risks For general use you can't expect Joe Average to even know about imbalances, let alone care about them. Bottom line: GIven the fire risk of overdischarging, commercial systems without management are likely to fail the "insurance test" (ie, your liability insurance as a seller and your buildings/auto insurance as a user)

[@woodywoodwood7525]

Totally agree with you. BMS can hide a bad cell in a pack. I use balancing Leeds.

[@kennedy6971]

I am a electric bike person.. Every battery i build for myself has no bms.. I run extra leads to each bank to test voltages etc.. Roughly once a month i manually check each battery bank manually with a volt meter. I can use those leads to charge as well. 2x a year i manually charge each bank.. Ive had no problems.. Only problems ive had were with purchased batteries with bms.. I think as long as u keep a eye on things (and you have discharged and recarged all the cells your using to build your battery. Matching the cells is a MUST!! I cant say that enough. Match your cells and 95% of your headache is gone.

[@BraveRock]

I love technical videos like this one.

[@frankallen422]

most 18650 have a built in fuse right under the top. I have had many battery read 0 volts. take the top off and under the tab it reads 3+ volts.

[@jehugarcia]

True that

[@moodesigner]

+jehugarcia you should def do a video about that

[@robindrake1407]

frankallen422 u

[@DEPanswers]

My god you've saved me some money and some space in my trash can. I just stuck a knife under the cap and now they work.

[@rizgarj8050]

If they have Fuse under the cap. Do we have to add an additional fuse outside?

[@BobOBob]

Except -- YOU ARE the BMS. Most people do not *want to* stay as aware of the internals of their tools. A tech-minded person like you or me is interested, maybe even /driven to/ know, and with decent monitoring would usually catch problems in plenty of time. For my own toys, little meter/monitor/alarm cards cost about $2 on ebay. Oh, wait - you just showed it and called it a buzzer. That one. Works great for me.

[@netsurfer10000]

very well said.

[@darinmbicknell]

+Bob O`Bob But... if safety is the issue then which is safer. Jehu or the BMS? Depends on the application and the person. Ideally we would like to have individual cell management not just pack level or parallel column level diagnostics so you can detect issues and resolve almost in real time or as you say catch it in plenty of time. I appreciate that Jehu is being clear if you are unhappy with that level of "uncertainty" then you get yourself more data possibly with off the shelf items. Bigger issue cost as well as time required to put that sort of data management in place and getting the right BMS and wired it up correctly. Plenty of mistakes can be made wiring up balancing leads just watch any number of DIY e-bike videos KZbin for that.

[@BobOBob]

If safety is the issue ... go find the video where Jehu explained all those little fuse wires, one for *every cell*

[@darinmbicknell]

Yup.

[@baronvonlimbourgh1716]

It is just regular maintenance that comes with owning a car..

[@robertbrowerjr554]

you can just bypass the bms on the dis-charge side only to get max output and still have charging data going through the bms for charging safty!

[@JawadAhmadsahibzada]

i agree, once i asked you sir "how many cells in series for 24v ups battery pack ?", you said 7S , and i made it. then i couldn't find BMS more then 20A in Pakistan, and i need at least 100A continuous , so i started using it without BMS, and it's been more then one year and it's still working great - i added just a fuse for protection, that's all. i didn't find capacity of each cell of the pack, i just fully charged and made sure that voltage drop don't exceed 4.15,. i learned - if you don't charge your battery's each cell more then 4 v then you don't need BMS and this will prolong your battery life too.

[@peterroulund1156]

Very good and informative videoes you make! I'm looking forward to making my own DIY batterypack from used cells thanks to your videos - well done Jehugarcia!

[@jehugarcia]

Thanks

[@Kyle-gq7tk]

Hey. Thank you so much for your videos. I'm learning so much about batteries and plan to take on some projects in the near future. I'd love some tutorials/projects for complete amateurs!

[@nicholaswong4214]

What are the different capacities between your 18650 and Voltronix packs? I do wonder how multiple chemistries would work at different capacities. In theory, the 18650 can definitely act as a booster pack to supply large current spikes.

[@jehugarcia]

+Nicholas Wong 20Kwh on Prismatics Vs 24Kwh on 18650 Tesla Pack

[@nicholaswong4214]

+jehugarcia I'm assuming the voltages are close and packs are wired in parallel. Have you ever run the 18650 pack at lower capacity than the prismatics?

[@lukewalker1051]

Your videos are brilliant. Thank you for the service you perform to the electric community by educating us.

[@edwardallen2425]

I used copper tape to make my connections without soldering each cell. Have you tried that yet?

[@terryterry1655]

Where to buy

[@Sinista123]

My thoughts.. The reason for balancing is to prevent cells from overcharging. If some cells are at 100% already and the rest is at about 95% the charger will still charge the battery pack, because overall the pack is maybe at about 96%. So the full ones will get overcharged.. That's the theory... OK. good quality cells are never ever that far away from each other. And they don't break right away if they get charged a little bit longer. If you want to charge your cells super fast with many amps, a BMS is probably not bad but it will not balance the pack in such a short time. If you have the money and space in your vehicle, or you use many different cells you probably should get a BMS for maximum battery lifetime. A BMS can be really cheap and also really expensive. It depends on the quality and every BMS can break. If you have enough space, you could invest the money in extra cells, instead of a BMS. If space is very limited, it's probably also better to use all the space for cells instead of a BMS and just monitor them every few months.

[@perseverance8]

A BMS is virtually essential in consumer or similar products equipped with potentially volatile batteries types like lithium, however, I personally do not integrate a BMS into my packs, it adds cost & weight, I build my packs for my ecycles, one of them is a Headway 38120 16s pack, for its ability to provide excellent high amp performance, additionally, I run 18650 pack(s) in parallel for their lower cost of capacity, providing for an extended range, they are connected to a custom built regulator before being supplied to the motor controller, this regulator has the ability to connect four packs supplying four outputs, it allows for independent voltage & current programmability with data logging. My charger has integrated balanceing, like used in the RC world. All lithium batteries I've seen used in RC do not have an integrated BMS, they have a balancing plug & main supply, they commonly have integrated fuses.

[@sethlavinder]

Jehu, are you familiar with Bioenno batteries? I think they are LiFePo4 packs. I bought one that looks exactly like a 12v7amp sla pack. It’s rated I believe 13.2 at 8 amp with less than 1/3rd the weight of an equal SLA. I also bought their 13.2 Vdc @ 30 Amps pack, it is not a SLA drop in replacement. It was what I consider expensive. The 30 amp pack cost around $330 with charger. I found a NOS 35mm camera case and it fits perfectly in camera bag. I would love to build a Power wall ! I am amateur radio operator and would enjoy a project that would allow my entire radio room to operate from battery. Kind of a dream right now. I have a small portable radio made by a company called Elecraft that’s in Northern CA , it is an amazing radio but it has very strict max voltage. Anything over 14 volts and you are risking major damage to a $1,800 piece of portable radio gear. The math isn’t working out in my head well, but is there a BMS or DC2DC precision regulator that would permit building a very small 18650 pack that could regulate at 13.8VDC at 5 or 10 Amps? I will keep watching your videos for more information, just discovered your channel a few nights ago! Very interesting and professional content and production credit to you for all your efforts! 73 de Seth - W8FG

[@rocketrose2165]

Jehu you are my hero. I've come up with a way to use 18650's that I harvested from old laptops to power my ebike without using a BMS. I have thousands of cells that are already balanced charged. I just needed a way to use them like flashlight batteries. Use them, take them out and put in fresh batteries, recharge the depleted ones. I tried a variety of ways then found a simple system. No solder, no BMS and relatively easy replacement. I wouldn't suggest this for large arrays but for a 10Ah 36v system it works perfectly. 90 minutes replacement time, start to finish.

[@Ordinary-Hendrik]

What is the name of the battery monitor you are using? Where can I buy it? Thanks and appreciate for everything you share!

[@jehugarcia]

+1000delight link in the description

[@Ordinary-Hendrik]

+jehugarcia Thanks!

[@Espr14]

When the battery is not used, you can switch them to fully parallel and they will balance themselves automatically over time. Then you don't need any management or balanced charging. If you balance them regularly, there won't be big voltage differences so you don't need to worry about high currents during self-balancing. All you need is one big switch which connects the battery for use (charge or discharge) or for self-balancing.

[@kevinroberts781]

Just make sure you have some kind of over volt and under volt control. It doesn't need to be called a "BMS". Know your battery. Monitor your battery. That is all you need.

[@acwrobel1]

As long as you don't have a catastrophic overheating (decent protection built into good 18650's) you won't have a very dangerous situation. A BMS is an added layer of safety. If the individual 18650 can self-manage, then it's not "essential" but is still beneficial. However, an emergency fire suppression system might be a decent idea, and it's not a one-or-the-other sort of thing. :P

[@midway241]

I really like your videos

[@necromecro]

thanks to you you share a the info all you have :) what should we do if a battery is unbalanced?

[@JuanJDumeP]

hey what is that module/app that you use for amp voltage meter that you have in your samba car on the android Samsung tablet that's really cool would like to integrate on to my ebike if it is possible thanks biggg fan of your channel and work

[@jehugarcia]

+Juan J Dume P It used to be called Android Dashboard, but now its called Torque Pro minibms.mybigcommerce.com/products/EV-Display.html

[@JuanJDumeP]

wow this thing is cool thanks Garcia

[@fredbleichert7805]

In your Samba did you use recycled 18650 cells ?

[@ukaszdabrowski7523]

You can film the movie as you were dispelling the build up of VW to the race. After the train, each part of the body will work and how the session will work together

[@1981dasimpson]

it also depends at what current rate you charge at i have also noticed

[@gwizz7804]

Will a cell made from 100 x 18650's arrange in 10 parallel and then connected in series to create 37v balance itself or will I need a monitoring system?

[@FM-fn7eo]

ok. if I don't use a bms , for example to connected 5s 18650 21v with bms and adaptor for bms . how do i charge them tougher and not separated ? thanke you

[@kurddata5228]

Hello. I have 3 beautiful questions: 1. Can I use battery holders instead of connecting the terminals of a battery cells, then join the wires + -? 2. Is it necessary to use BMS while the batteries can be pull out and being charged with Li-ion Battery Charger? 3. Can ESC used in RC projects be an alternative to manage the outgoing voltage and current of the battery? Thanks in advance for response!

[@jehugarcia]

Yes -no -yes

[@kurddata5228]

Many thanks

[@fazuelle]

how do you charge your batteries in the samba or the diy power walls?? do you charge them all together in one single block?

[@jehugarcia]

+AndreyKandauroff yes

[@sveingjrannordb8101]

Very good, i like the thorough linking in the description.

[@Vigilante82O]

so BMS is only need it when charging in series configuration right

[@a.noureddine6821]

Useful video I have an electric scooter with an original 48V polymer battery that works well. But when I put in a lifepo4 48V battery it does not work. What could be the problem, knowing I charged the battery completely and I tested it?

[@kingalbert9357]

Can I use those batteries for a solar panel kit for my house projects

[@anwarigroup]

One of the problem is that all batteries are not chemically identical and as well voltages are not same. Other problem is overcharge and over discharge problem. When batteries are connected they adds up with each other make more difference in voltage than a single battery. Using diodes, resistors and transistors to manage the power, and manage the charging of the batteries are not a bad idea. At least you have a protection system. Mostly when lead acid batteries overcharge they explode. So also the lithium batteries not to be left overcharged or over discharged. After they charged the voltage will be reversed, this might damage the charger and or the batteries or components connected.

[@dnetne5508]

A little funny question: Can I like connect the negative wire to the main negative(even if 230v and 200amps) Like to save on wires for the same negative pole? And like have the positive wires at each batter(like 3.2v at 2amps)?

[@timothy790110]

So, if you are your own BMS, how many times a day do you have to check the cells?

[@jehugarcia]

None

[@timothy790110]

hmm, not sure I understand. Maybe you can help me understand. Im looking to make a 12v, 160ah lifepo4 batterybank, using 4 of these 3.2v cells, its for my camper van. www.ev-power.eu/Winston-40Ah-200Ah/WB-LYP160AHA-LiFeYPO4-3-2V-160Ah-TALL.html?cur=1 that I will be powering with 4x100 w solar cells, via the tracer www.ev-power.eu/en/By-Brand-Manufacturer/GWL-Power/MPPT-Solar-Regulator-12-24-V-Tracer-BN-40A-Input-150V-TR-4215BN.html?listtype=search&searchparam=REG-TR4215BN Now, they recommend getting this 300 dollar BMS system. www.ev-power.eu/Battery-Management/BMS123-Smart/123-Smart-BMS-Complete-Set-4-cells-with-Bluetooth-4-0.html?&listtype=search&searchparam=BMS123SM-SET&cur=0&&listtype=search&searchparam=BMS123SM-SET do i need it? Obviously Im not sure what im doing, but im willing ot learn, especially if i can save 300 bucks! they also have these things www.ev-power.eu/Battery-Management/

[@jtmcfalls2230]

Where is the link for the testers used in the video.? Thanks

[@DamacusSquared]

If you have a multi pack, multi cell battery its just too much extra complication to monitor every single little insignificant cell individually. Monitoring the packs is fine but you don't need to use a dedicated monitor. A simple little tester like you use is fine to test each pack occasionally aft multiple charge and discharge cycles.

[@warialinth]

Yeah thanks to your "little bit" over-extensive cell selection in your packs you have almost all of them in same shape... so they are not that much susceptible to go out of balance.

[@deanbornman77]

You talking about series. Do you need a BMS for parallel?

[@ikentfix]

How do you charge you batteries? (batteries without BMS)

[@Dduerto]

So your batteries have no sort of chip to control the discharge and so on? Do your batteries have a cooling system?

[@agustinmoralesrodriguez1242]

That's exactly what I thought. LiPo4 batteries can be managed through modern controllers with temp sensors. They have to change the parameters in order for the batteries shutting down with the controllers set ups and not through their bms. Simple redundancy. The controllers will stop in case of over or under voltages, shorts and high temps. I think I can get away without a bms on LiPo4.

[@brianmendell1449]

Hey jehugarcia I have a question for you and for the viewers of this channel... now I have a mobility scooter that asks for 35 ah gel batteries.... ok now I just bought brand new batteries on may 14th and as of last week they were nearly totally failing cause I couldn't even get 2 miles out of them... now I've came across 70 18650 lithium cells for 20 bucks which is a great deal from my research lol... now the batteries mainly came in 2 battery packs from those ride on scooters that all citys have one has 30 cells and is 7800 mah at 280 wh at 36 volts and the other is 28 cells and 8800 mah at 317 wh. Now with my deep cells failing what I did was only hook up one deep cell battery and basicly half of one of the lithium battery packs (around 15.5 volts) and now after about 3 or 4 cycles to both deep cells I went and hooked up just my deep cells and I got nearly twice the ride distance out of them (the 12 v deep cell batteries) now what do you think could have happened to those batteries? Cause now they are getting better milage. Please help me understand.... besides that jehu thanks to you I'm in the process of making 7s 10p battery pack for my coupe de ville lol (my mobility scooter) it should be around 25 ah and that should be plenty of power... oh my scooter's 24 volt controller's out put is between 90 and 2000 watts... yea I know that sounds like a lot but that is what it says on the side of my controller.... so what does everyone think? Will my 7s 10p battery pack be enough?

[@zayres29]

how would you recommend building a lithium pack for a 12v car audio system? something that could support 8000 watts

[@jehugarcia]

easy 3S30P (90 cells total) of these j35.us/18650-LG-HE2 , thats good for 10,000W but you'll need this special charger j35.us/PowerLab8 between your car batt and your audio battery.

[@zayres29]

jehugarcia would the lithium be an independent electrical system from the cars battery or could the lithium be charged by the alternator while the car is running

[@jehugarcia]

+zayres29 it can be charged by the car but it has to go thru that charger because your cars voltage is different and it would damage your lithium ion cells

[@zayres29]

jehugarcia sorry to keep bothering you with questions but could a pack be made with multiples of 4 cells to get the right voltage the more voltage supplied to the amplifier the more power it makes obviously so that being said if I had a lithium pack that charged at a higher voltage i.e around 14v-15v I would just have to balance the individual packs that would be "seriesed" together to make the larger pack thanks for all your help

[@jehugarcia]

yeah 4S would work, fully charged would be 16.8V. if your audio equipment can handle that voltage there should be no problem. You could also just not charge your 16.8v battery all the way up maybe just up to 15V but then you will only have 80% of its capacity so you have determine how long you want to run your system and make the battery 20% bigger, that way you get your desired run time

[@adamadamhoney]

Don't know if this has been mentioned here, with those little cell balance monitors or even a small charger can be left connected and just break the negative balance lead with a switch to turn it on and off as needed, really handy and cheap. Ive built projects and hacked a small hobby king balance charger into my enclosure after removing it from it original case and use switching to set to charge mode, cell check and run (use of battery). Cost about $10 bucks, great for small projects / batteries. Maybe not a car though :D

[@RamonAlcaide]

an I use, lets say, a 10S bms for a 6s battery pack, by not using 4 of the balance leads, and powering it with 22,2V?

[@RamonAlcaide]

Can*

[@carlosrodrigues77777]

hi @jehugarcia im a fan of your channel. id like to say that you are an excelent guy, wich can explain the things really simple and really well. i've seen a lot of your videos. i needed your help cause i have an electric unicycle model TG T3 and battery is really bad. my plan is to extend the range of it. i dont mind to carry a battery on my backpack, thoug i prefer get some space to it by drilling some plastic. also do you think is better use lipo batterys like Rc models or use the standart stock 18650 batteries? is better to use bms or use a IMAX b6 and the portable battery logger or use a bms? thanks a lot. hope you can help me out. have a nice day.

[@mohamadtubless]

Hi Does imbalance happen in M18 Milwaukee battery packs ? If yes what should we do to fix it ?

[@nismatarifi3120]

Hi, Hope all is well. All your vids are informative. I have a question about battery ppwer and how to use the max amount of power sending it to the end user. If one had 120000 that each produce 0.5V and 0.1 amp connecting 28000 to achieve 2800 amps and 92000 to achieve 46000 volts how would one go about achieving the max power lets say 120+ mw and how would you go about delivering that power to the end user?

[@AS-cy1jt]

looking for suggestions from the person who got me going doing this,, that's you Jehu, anyway, I'm converting my boat to EV, 36ft islander sailboat,, I want to use shorepower, solara, wind, hydro generation,, I've bought 600 new panasonic 3.4A 3.7V, I made up 20 packs of 30 cells in series, I don't want to let the cells drop below 3vdc or charge over 4.1 vdc, I'm looking for a quality bms to keep these safe and working for a long time.. do you have any ideas,, ok I know you got lots of ideas, what do you think, i've got your utube link on my desktop and notifications bell for new videos,, btw awesome samba,, I used to have a 63 v dub bus,, wish I still had it now,,, :-(

[@jehugarcia]

Batrium.com

[@AS-cy1jt]

oh yeah, I got 4A glass fuses for each cell, sunko 708A spot welder, weller iron,5mm zinc ribbon, 10awg buss wire for + side. cool,, just confused over bms system.

[@AS-cy1jt]

I've been looking at batrium,, saw it on hbpowerwall and joe,, just needed your ok, tx ,, awesome

[@yousefyahia7255]

You are wonderful, I really like your videos. well work.

[@johnwoods6751]

Could you use a multiplexer to use the meter to scan a whole system?

[@MFEeee]

+jehugarcia You ever considered Headway cells?

[@jehugarcia]

+Michael Espinosa No, I remember them being hard to order as i couldn't find a local dealer, maybe its different now

[@1981dasimpson]

i wouldent say dangourse but will hewlp to lengthon the life of the battery pack as it will not allow some cells other other to over discharge

[@rascal1234]

This is the same issue I am grappling with my ev convert (1973 triumph spitfire). I have an orion bms, but it constantly draws 150 watts and can destroy cells if it goes bad. I know someone who had that happen to them. I also have lifepo cells from one manufacturer and from the same production lot. All cells are within a 1/100 of a volt from eachother. Not sure it is compelling to use a bms unless you are racing or charging faster than 1c.

[@jehugarcia]

+rascal1234 Yeah, BMS systems are often more trouble than help, from what I hear. For a daily driver i feel going with biggest battery and staying off the edges of charge and discharge curves is the best and easiest way.

[@michielhoynckvanpapendrech1069]

Wondering if I can use a 2 K Nissan Leaf batterypack to store my solar energy instead of the Tesla power wall ? Thanks, Mike

[@PeterOrrick]

Can I connect the battery directly to the hover board, bypassing the BMS?

[@ericspearsairborne]

I'm kinda new at this but if your running solar and use the 18650's banks wouldn't the charge controller do a large majority of your Batt maintenance( charge, monitor, trickle etc) in talking like the nice expensive Outbacks and the like, not the $19,99 ones from Harbor freight

[@plasmaguy5]

Very good info thanks

[@prasathtex2558]

Hi Sri if you can please do a video how to repair the Prius battery

[@MrBrymstond]

I seen brand new batteries fall out of balance right off the start because the had a different internal resistance.

[@etiennelauzier5698]

Thank you very much for what you do. Great job, keep it up !

[@RodneySolarCircuits]

thanks

[@rtoebak76]

Hey my friend. Would you think pulling out the Battery management system will make it run better? Rc world has esc also for not burning things or blowing up. My ebike bafang bbs02 750w 48v has i believe an esc and the battery a bms. I can check voltage on my display nog going below 39 before it drops put. Balance charging my 13s5p ebike battery like my lipo's would be the same thing. My question is will a bms limit your motor from blowing up. Confused a bit.

[@VroomvroomNY]

Do you recommend any good books to learn more about batteries?

[@bereal1251]

I just sub to your channel love the videos you put very well put and easy to understand ..I'm trying to build a skateboard battery pack using the LG 1860 3000mah how many will I need to make a pack to last at least 10mile range ? Thanks for any information you can give me

[@ShenZhenDigiCasting]

up to 96S LFP and NMC BMS

[@shawnhopping5984]

Can you give me a reference as to who could repair a lithium battery for me?

[@parasar_the_destroyer]

Hi your videos help a lot. Thanx man. But i need a little help from you. I have few batteries and few more will be there within days, now through i max b6 it only gives me the capacity of one battery at a time. And its time consuming. How can i get to know the capacity of few batteries together. 2nd suppose we have 4 batteries with 2ah, 1.2 ah, 1.6ah and 2.2ah now if we connect them together in parallel we are going to get the summation of amp hr like in this case 2+1.2+1.6+2.2=7.1 ah, Now when we put a load on this pack the 1.2 ah battery will go down first now the other batteries will try to charge it, and that should effect the capacity of the battery pack, is that so? Please help me

[@kamikazekunze]

Holy motion sickness Batman....steady cam in the near future?.....great content as usual. 🤓

[@jehugarcia]

+Alex Kunze Soon, once I can spend the proper time to produce these videos, production will go up.

[@lorenswastesson8484]

Hello! just need to ask. If you put Lifepo4 batteries in a regular car with alternator. And just use bottom balance how to control so the batteries not getting over charged? Best Regards Lorens Wastesson

[@johnwoods6751]

A balance system would be nice if it could delete singularly a faulty cell.

[@lollol-tn5op]

I am working on battery pack for electric scooter and bikes and the BMS save some customers because I saw one row gone gone before the others no voltage at all . If you try without BMS they will overcharge the other because they let the power going trough . example 10S become 9S and wthout BMS the charger will push 42V on 9s if is only 1S you don't need bms

[@scavanger1000]

Would it be possible to wire up a bunch of 18650s as a backup powerbank, that supports level 3 fast charge?

[@jonahwhale]

I did a 'bulk charge' on a 7s 24v tesla battery pack for a couple of years, then discovered that one of the cells discharged to 0v (must have had a bad 18650 that drained the cell), and the other 6 cells were charged to 4.6 volts. So I probably damaged all 220 18650s by trying to skip the BMS.

[@CrankyCoder]

if you have 24 batteries in a cell, how do you balance 24 instead of just 3? more connections?

[@JoseGarcia-px9xj]

so basically balancing the cells means draining the one with the highest voltage, but if you have 100 cells parallel working like one(cell) you need a big resistor for draining this high voltage cell, I am right?

[@jehugarcia]

+Jose Garcia not high voltage, high capacity, it’s the same voltage as a single cell

[@isidrorodriguez510]

Hola como estas dónde yo compró las baterías para hacer un banco de baterías para la luz de mi casa y cuanto me cuestan

[@jehugarcia]

Estos son los mejores precios j35.us/MARCH-Deals

[@seans1102]

As far as using a DIY charger with a bms couldn't you charge a single battery at a time and take the balancing function out of the mix and then use the under over function only. Then manually log each batteries mah and sort them into balanced groups? It's more time consuming but your batteries would last longer. Or build a circuit that turns off the unbalanced batteries but have a deserve pack kick in with the amount of cells needed which would give longer life to the batteries and also longer runtime for the vehicle or generic device.

[@jehugarcia]

draw a schematic of what the wiring would need to look like and spec the devices required to do all that switching and you will quickly realize why no one approaches this problem that way.

[@biaggiwins]

Learning so much from you. Thank you. SUBSCRIBED

[@rocketrose2165]

I've come up with a way to get around the whole BMS issue: Charge the batteries individually. All you need is a way to interchange the batteries. I'm dealing with an eBike so the most I'd use is at any one time is about sixty batteries and that's only if I'm going a very long distance. Have a look: kzbin.info/www/bejne/eZi3h56HoK-Yn7s The problem most people get into is reclaiming old 18650 batteries from laptops and then soldering them into a brick. When one goes bad (and one always goes bad) they have to take the brick apart and start over. Forget that. I got the idea from a guy in Sweden who put his into a box with contacts above and below but that didn't seem practical with the jostling of a bike it seemed like just a matter of time until a connection was lost and your back to peddling with an extra fifty pounds. I use 3/4 PVC tubing, some nuts, bolts, brackets and wire. I did have to solder the contact wires but other than that no solder needed. When the cells go down I can take them out, recharge them individually and they're ready to go again. No BMS needed. When one goes sour I sell it for $.50 a pound to the recycling dude. I've put up a couple of videos. Still waiting for the right connectors for my new bike. The bike I chose is the new Sondors Thin. It's a 36V so I use ten 18650 batteries in series. I'll go with three packs per side in the saddlebags. Should extend the range three fold with only a quick stop to change the battery connection on the bike. I've always admired the way you tackle issues and I get a kick out of your videos. Keep up the good work.

[@heavycurrent7462]

What if we just create a switch that disconnects the series connection and close a parallel connection? This would automatically balance the batteries.

[@abdlkrimaldhrey1224]

Great, thanks. .

[@Projects_and_Pistons]

What is the gauge on the wire use use as a fuse? or what fuse is it?

[@jehugarcia]

+Charles Roberts I used the legs of 1/8 watt resistors, they burn at 6 Amps, found here j35.us/1k-Ohm-resistor

[@Leo-mh2mz]

So, then couldn’t we wire 4, 3.7 18650’s for. 12 v system. That would be 14.8v, would that work for a 12v system?

[@jehugarcia]

Fully charged is 16v which is too high for most 12v devices

[@Leo-mh2mz]

Ok, again thanks for your help!

[@johnsmithy9304]

Where can I buy new cells 18650s I am building a camp trailer want to put solar on the roof. Need 7500 kw 110 volt and low voltage. 12 volt. Drawing a massive blank. Also love the VW van if you want oak basic roof racks happy to send a nice set.

[@williamcastine7591]

Question if I have 2 lithium phosphate battery packs 32 cells each headway and I'm using them for car audio. I have balance boards but want to keep a battery up front for the car alarm ect. What else do I need to make it safe and keep the maximum charge and discharge for amplifiers.

[@vikramrosebud]

The reason I believe, why your samba does not require a BMS with multiple chemistry is probably because the brick type and the 18650s are in parallel to each other, where in they sort of self balance. Of course safety is taken care of, but when you mix multiple cell capacities in series and connect it to a charger, then what can you do?. For example, a 1000mah cell in series to a 2500mah cell?, the 1000mah cell is going to charge in less than half the time and the 2500 is going to continue and the 1000mah will get hit with currents constantly. Hence, the need for a BMS

[@scottdilinger5920]

How many miles have you gone in the year with out a BMS

[@jehugarcia]

10k

[@sham1234567891]

Buenos Dias Jehu. I need a 18 volt pack for my Bosch cordless drill. What type of bam do I need. Thanks.

[@ralphbrown2714]

Great

[@isidrorodriguez510]

Gracia cuál tu me recomiendas el inversor es de 24v y cuánto paner solar tengo que poner para cargar la batería Vivo en la República Dominicana y hay muchos sol a qui

[@laubillum8197]

Question from Denmark. I have acquired an old electric cemetery garden car. it runs on new 3 x 12 volt 100ah battery in series. but i would like you have an BMS installed, what should i use in this case? I do not know anything about it, but i want to have en an experienced point of view, for what to use. and not use, mayby a link to a site? Kind Regards Lau

[@mamun2a]

I want to make one 6cell 11.1 volt, 4400mah battery with a laptop batteries. It will be used in motorcycle as replacement of lead acid battery. Do I charge it from bikes charging system? I don't want to use any bms. Please help

[@Abricos4440]

If I have 300S what do I need to use ?

[@matter45]

battery management system ensures the longevity of the cells. the characteristics of the cells will change as they age, and a BMS system is vital to make sure that those developing differences dont build up over time. for the average consumer who wants batteries to last a very long time, IT IS A REQUIREMENT. the average consumer is not going to look after the cells and do top and/or bottom balancing. A battery monitoring system is a must regardless.