So I decided to build a Lithium active balancer with unnecessary big gate drive transformer. It manage to pump 1A of current with 100mv voltage difference between cells.
So I decided to build a Lithium active balancer with unnecessary big gate drive transformer. It manage to pump 1A of current with 100mv voltage difference between cells.
Big gate drive transformers are easier to wind;)
The quiescent / operating current is around 37mA for the PWM driver chip (SG3525) when connected to the gate drive transformer and around 16mA when it just dangling loose.
The gate drive transformer has a winding ratio Primary:secondary 2:1 with 8 secondary controlling individual mosfet. when I wound the transformer I originally wanted 1:1 ratio but turns out it draw to much current from the chip (around 100mA) and it got really hot! so I decided to just put 2 winding in series for primary side to reduce the current.
The switching frequency is around 35khz and it’s adjustable. I initially use 50khz but the quiescent current is to high to be efficient (around 60mA) so I tried to tune in the frequency and got the sweet spot!
That’s “Li-ion”, not “lithium”. Lithium cells are not rechargeable:
https://old.reddit.com/r/AskElectronics/wiki/batteries#wiki_lithium_vs_li-ion
It’s always refreshing to see some nice chonky electronics.
Got a circuit for this? I’m interested in the active balancing.