BMS for Lithium ion battery
Selecting BMS is not only dependent on the battery amps or Ah. It also depends on several other parameters like maximum charging current, maximum discharging current of the battery, peak current i.e. by what rate we can charge or discharge our battery like 0.5C or 0.8C or 1C. This capacity C rating is provided by the battery provider.
As specified above 36 Volt, it can be made up of LFP as well as NMC cells.
LFP chemistry offers a longer cycle life. Nominal cell voltage is 3.2V
Nominal cell voltage: 3.2 V
Cycle durability: 2,000-12000 cycles
Specific energy: 90–160 Wh/kg
Specific power: around 200 W/kg
So with LFP 3.2V cell we need 36/3.2 which comes to 11.25. That means 12 cells is must me connected in series so the 12S BMS will be needed.
And if NMC cell 3.7V is used 36/3.7 which comes to 9.7. That means 10 cells will be fine in series so 10S BMS will be needed.
Now other factor is current carrying capability, keeping in mind the above points of charging, discharging, peak current. If you think that you need only 8 ampere of continues discharging current and 8 amps of charging current then 10amp or 15amp or 30amp will work fine.
Finally select 10S30A BMS if you are using NMC cells or 12S30A BMS if your are using LFP cells.
Availability of desired current rating of BMS may vary so try to choose nearby rating of above calculation.
Still have any doubts comment below or direct mail me.