Li-ion Balancing and Protection Board BMS SIMULATION (How it Works)

Music - Joakim Karud

The Orion Battery Management System (BMS) performs three primary functions:

It protects the battery pack from being over-charged (cell voltages going too high) or over-discharged (cell voltages going too low) thereby extending the life of the battery pack. It does this by constantly monitoring every cell in the battery pack and calculating exactly how much current can safely go in (source, charge) and come out (load, discharge) of the battery pack without damaging it. These calculated current limits are then sent to the source (typically a battery charger) and load (motor controller, power inverter, etc), which are responsible for respecting these limits.
It calculates the State of Charge (the amount of energy remaining in the battery) by tracking how much energy goes in and out of the battery pack and by monitoring cell voltages. This value can be thought of as a fuel gauge indicating how much battery power is left in the pack.
It monitors the health and safety of the battery pack by constantly checking for shorts, loose connections, breakdowns in wire insulation, and weak or defective battery cells that need to be replaced.
There are also secondary functions that the BMS performs:

Balances all the cells in the battery pack by intelligently bleeding off excess energy from cells that are charged more than others. This provides the maximum amount of usable energy (capacity) from the battery pack since the pack is only as strong as the weakest cell.
Monitors the temperature of the battery pack and controls a battery fan to regulate the temperature of the pack. Additionally, it constantly monitors the output of the fan to make sure it is working properly.
Provides real-time information and values to other devices such as motor controllers, chargers, displays and data loggers using several different methods (CANBUS, analog outputs, and digital outputs).
Stores error codes and comprehensive diagnostic information to aide in fixing problems with the battery pack should any issues arise.

[sucim]

Wow this is really great, did not find any explanation on how these work and then suddenly there is such a good video, thanks a thousand times!

[xqhmrcn]

best and simple video that explain how it works

[no_more_free_nicks]

Awesome explanation, I got how balancing works in 2 minutes with all the necessary details. Thanks!

[redvalley]

Wow, I fount it randomly on timeline. but it's very necessary for me
Thank you

[domfree]

so informative to know about balance charging

[it-diagnostyka]

after reaching 4.25v, a system with a 510 resistor switches on, which loads a single cell and discharges it so that it does not exceed 4.3v

[nucleardoomertv]

Hi, what exactly happens when first cell reaches max voltage ? I heard some boards will just stop charging even other cells can have for example 3.7V.
Or will just board limit current from source to value of current that goes through load on fully charged cell to maintain charging of other cells ?
I think some cheap board on Aliexpress are first mentioned type.

[nitinsonwale]

Great Awesome.
Cleared many concepts in just 2 minutes Animation video. Thank you very much !!!
Could you explain how battery voltage sensing done in lithium ion BMS ? Please !!!!

[We-Do-NOT-Consent-]

Hi, I have a left over 48 volts BMS and charger from an E-bike.
And I wanna use the 58 Volt charger to charge a 24 Volt 18650 battery pack.
Can I use half of the BMS to charge the smaller Battery pack???

[KoRtExXx]

Can I connect in parallel another resistors for faster discharge and balancing?

[Alksbbch]

If one cell reach 4, 25V, and other have 3, 4 volts. Then discharge curent of this cell be 0, 08 miliams and charge curent be let say 2 amps, and then this one cell with 4, 25 voltage can go up to let say 5 volts (because charging curent much higher, than discharging)?

[martinjaure]

Hi, I appreciate your video. I had a question that maybe you could answer if you had the time.
If you had one series that’s out of balance and the BMS shuts down charging. Could you plug in the BMS and then only have connected a series that’s out of balance? Would the BMS then charge the connected series to the cutoff voltage?
This way you could rebalance the pack without needing anything right?

[sandroz]

So on these non-intelligent bms the only way to balance the cells is to fully charge the battery and let the ones that exceed 4.25 volts discharge?
if the difference is a lot, the bms cannot balance because if the bms detects a cell that exceeds 4.25 volts it stops charging, is that correct?

[rosekreuze]

how about under-charging to 4.0v each parallel? does the bms still balance all the batteries? lets say i plugged it into 28v?

[portablelithium]

Nice video. answered a lot of questions I had.

[khaled]

Great sir thank u . U solved my problem

[ND-ktng]

Best explanation that i've seen on this subject. I'm gonna try to connect two 7S2P battery pack parallel with individual bms. There may be some cappacity differences between battery packs because one of the pack is already working on my e-scooter. The question is ; how about the possibility of charging the packs each other in case of older battery pack cappacity decrease while using ? Any protection on BMS for this ?

[viswanathanramakrishnan]

What would be the current requirements for the batteries which are in this set-up? Which type of power supply is needed to charge this battery pack and the voltage /current requirements of such a power supply? If all these are enlightened to the DIY ers it will be of a great help to them to try.

[Skiel]

Nice demostration, so I've been workin on Narada Battery LiFePO4 NPFC series, IDK if you have a single line diagram of these batteries because I've tryed to undestanding its BMS. Thank you in advance.

[sayantan]

I wanted to build a 18ah 36v battery pack using lifepo4 6000mah 3.2v (32650/32700) cells.
I wanted to make 6ah 36v pack of 3..
And I wanted to charge faster...
What should I do?
Please help me out