Do you NEED a BMS for DIY Li-ion Batteries?

Hi, plz I have a question : can I run a Xiaomi scooter (250 watt) with 36v hoverboard battery?? ( I make path just a 2km distance in day) , plz someone answer me. tnx

balancing the cells can be naturally achieved by connecting the cells in parallel right, instead of using dedicated logic for than in the BMS? The cells will charge other connected cells with lower potential until delta V is zero, right?

Why is that even a question? It's extremely unsafe to use batteries without bms...

Thank you for the information,I have in pass used balance charger,found safe,auto check, cell states accurate,real time information what's going on with battery,I found bms charging is not accurate,with time more use the bms through charging more discrepancy on the batteries,after using both types of battery system,I would recommend balance charger not bms my experience

the fact is there is no need for a bms if it is a serie connection
you have to be sure all cells are complete charged
if one cell is only 50% charged this afects the total cell serie
if a cell is 50 amps the bms is not charging that cell with 25 A
the charging from a 50 amps bms will be A/ cell numbers if 16
50A / 16 =3.1 AX 3.1 V =9.6 W a cell nice to see on a screen
but no bms is doing the same thing most likely your charger
will have a shutdown and a charts stage100 % is 100 % if you do not pull the plug.

i got a 56v 20ah 450 euro good batt pack with a 3A charger, but there is a bms of only 35amp on the battery. can i put a better one on it ? or take it off ? i mean i dont want to burn my brand new batt pack.. and can i still charge it on the charge port then, i got 1 2000w motor, and want to go faster. then 60 kmph. want to use all the power from my 2000w motor or what it can handle. and how do i take the bms off ?

Such a wonderful Video. Thanks a lot! :)

for a 12s4p battery, could you have a single 12s bms wire for each P or is it more important to have a bms for each P?

There should been an 80% charge balancer 😂

Great Video

quality content, thanks!

Hy. Can I connect 15ah BMS for a 25ah battery? Will the battery burn the BMS? Thanks!

You can not overcharge a lion, lipo or lifepo, at least no with lower current.. if you charge a fully charged liion with say 1 or 1.5A, it will just dissipate that as heat. No prob. This is the reason i built lifepo 4s 50Ah for my 1.0TSi, no bms needed

I think you just confused a lot of people on lithium ion batteries .and lipo batteries especially 5years when you made this video a balanced charger is for li pos for a regular 18650 lithium ion cell that doesn't have protective circuit build in then you get a bms and unlike five years ago just about everything that uses a chargable battery has some kind Guage on battery level

Far far too much waffle. You should have answered your question within the first 5 seconds, with "yes"/"no"/"perhaps". Then go on with concise info why. If you pad out info so badly you will loose me, and you will lose many others.

Can you explain the way you constructed the dual BMS system for the car? Also I was considering putting the outputs of a few finished battery packs (PB120B1) in parallel parallel. They use a DLX-HT-3S6A BMS internally. I am wondering the proper way to protect them, and if they would be switching between charge and discharge, since the BMS only has 1 pair of wires that are used for both the load and charging.

Considering that the BMS is what will dictate if you die or not yes you need one always.

I personally use BMSs on all my batteries. However, you can do just fine with balance charging. To prevent over-discharge, I have heard of a gadget called a low-voltage cutoff, which basically watches the overall voltage of the pack and cuts off the discharge current when it gets too low. I don't really like this because cells may be very well balanced when full, but the one with the least capacity will discharge to a critically low voltage long before the others. If the others are still high enough, the overall voltage may appear okay to the low-voltage cutoff, and it will allow the discharge to continue. I like the voltage monitor this guy shows that's wired in the balance leads. It will be watching each cell individually. If a low-voltage cut-off could be found that watched each cell individually and cut off discharge if any cell drops too low, that would be great.

Or you missed is bms bs or is it Bs not to have bms

On my OpenPPG paramotor, I have elected to only use my BMS for charging and then monitoring my voltage to decide when to setup for landing.....usually around 80 volts on my 24S battery. Using the BMS to monitor discharge, the BMS has failed me 4 times resulting in battery cutoff and emergency landings. (BMS units will eventually fail.....to me, that is unacceptable in aviation.) I do use an active balancer though that works 24/7. It is mounted inside of the battery....works great! Like you stated, everyone's situation is different.
Thanks for posting this video.
Bill

People say Lithium batteries don't do well in cold temperatures. I wanted to ask if this also will make it harder for them to charge up in cold weather since they already don't do as well in it?

Thanks.

Here’s a mind bender; what about a combination of lithium titanate and supercaps?lithium titanate (headway) cells for cold charging safety, and supercaps to handle the high discharge burst on steep hills.

I have a question i was an rc car nut when I was a kid I’m now 50 and want to get back into it. But 35 years ago battery were mostly ni cad or my Tamya cars were gas..I want to start slow I see some rc cars i like with small lithium batteries with just one lead and a usb charger.. dose a lithium battery with just one cord need to be balanced????

my 84V euc battery has two smaller wires (black and red) but they have no voltage. does this battery have to balance? I'm trying to charge it separately from the euc mother board connections. can you just connect the charger output to the battery and charge it?

So two identical BMS boards can be connected in parallel to one battery pack and it does not cause any troubles?
Also, is it okay to power each BMS separately from different chargers in theory it should boost charging amps and what is more important what if power each BMS with different power supplies for charging will it cause any damage to bateries or maybe overload the BMS?

Hey man. Can you send me an email and let me send ub a picture of the bms that came with my son's teemo skateboard? I am getting 40.84 volts on the entire pack, and the bms is allowing charging, but won't let you turn on the board unless it's plugged in to the charger. I want to know of an equivalent one I can purchase to get this back going. They want 300 for a new battery

Old video now but seems BMSs have a tendency to fail... In the RC world this is a non issue since electronic speed controlers have a low voltage cut off which prevents the user from over discharging the battery. Charging is also quite easy, just use the same profile you always do (just plug 2 plugs instead of 1). Do larger electric vehicles usually have a low voltage cutoff? Unless things have progressed in the last 4 years it sounds like a BMS is more trouble then it's worth?

Hard to get good bms these days

I connected my battery wrong-i crossed the red and black😢
Smoke from the battery, now nothing.
Is it now a paperweight,
or can it be saved?
Did I wreck the controller?
Help!!

i have an issue with me ebike. i have been able to narrow down to the battery pack. the bike will cut out and shut off if given any amount of throttle other than the smallest amount of speed. the battery pack test normal on the volt meter. im assuming its the bms that is shutting down the bike, as from what i can tell the batteries are fine. is this a logical assumption?

Bms will protect the battery when its fullycharge will automatic off 😊

Never use bms on my diys. Just set a limit charge cutoff on my battery charger and balance them once in a while.

I want to purchase your books pls send me how to buy them

Good explanation of what the BMS does.

It is all BS..... if it's at 36 volt 48-volt... Don't worry about it there a dime a dozen... 60 and up you might need one but don't worry too much ... just enjoy the ride

We would love one of your beautiful amazing books 📚 ❤️

Why lead-asic don't need bms?

But don't the batteries like that blue one next to you have a built-in battery protection circuit internal? Is that Different than a battery management?

MY EBIKE PROF PLS I NEED YOUR BOOKS AND HOW CAN I PURCHASE THEM PLS

hi... if i buy an ebike without battery....and I have to buy one from aliexpress, how do i choose / pick a bms or bms/battery? How come they dont come together? Any tips?

This is a great Video, You explained it so well, I often wondered the two differences ,I was on the same page as you but for me explaining this to a friend it was difficult . So I just sent him your video. Great job

Remove bms, add fusible 10 A fil red = gain 3 A 🤫 My trottinette 45 km/h to 52 km/h, zéro problem 4 years

External BMS and ‘bluetooth’ connection smart phone app

do I need a BMS for a parallel connection? (1S4P or 3P)

i have a question, i have a diy scooter trikke i am using three 48v 350 motor my batery is 48v 13s4p 10amps or close to 10amps with BMS discharge rate 35amps now if i accelerate quicke enough or most of the time while riding it shuts off, i will turn of the switch to off the back to ON and it will work again, do i need to replace the BMS on a higher discharge rate to eliminate the problem? please help thank you.

Great video. Could a power failure while riding be s symptom is a bad BMS board? Thanks!

The only video I have seen with the most important information on it! DIY batteries is not for the faint.... I need your help with the ebike 48v lead acid setup, popping and arching upon connecting, what is the best way to eliminate the risk of failure?

I have a bms on a 12v 3s2p pack and I have a balanced 3S wire hooked up because my imax b6 mini doesn’t allow me to charge without the balance plug. Here’s my issue I bought brand new Samsung 25r batteries so everything was charged properly but my B- B+ tabs read lower voltage that the actual pack reads. The pack reads 12.65v and the output plug reads 11.55v so I’m not sure why that is but I do have a few voltage alarms and one with a lcd screen but I’m not sure if the cells will discharge evenly so I left the bms on but I just don’t get why through the bms it reads lower voltage.

Hi sir. If i want to build pattery pack with bms. Do i need to buy cells that is "protected" or not protected? Thanks