Is there a difference between having one big battery vs 2 batteries in parallel?
I am building a "fan controller" and want to power a 12V fan with a lithium ion / polymer battery.
The circuit itself is working as expected but the voltage drop on even a 10.000mAh battery is so high that the battery triggers the undervoltage protection on startup when the battery is at about 3.5V.
I tried to smooth the startup current with capacitors but can't really get it down. (At least not in a size that still fits the enclosure.)
Is there a difference if I use for example two 3.000mAh batteries in parallel instead of one 6.000mAh?
EDIT: Thanks for the comments.
So first of all I am just a hobbyist and I am building this (at the moment) just with parts I had laying around. The fan is a Corsair 140mm fan that was included with the watercooler (H110i V2 I think.) I do not have a datasheet, however I will see if I can find one.
The DC-DC converter is a MT3608. I am controlling the PWM signal with an NPN transistor and the power with an NPN Mosfet (on negative) and an ATtiny85.
I do not know the C rating of the battery, it was just a generic seller in my country and that a while ago (5 months I think), but at least on 10.000mAh shouldn't even 1C be 10A? I can't imagine a fan to need more than that.
I'll try to get all the details and update the post then.
EDIT2: The Corsair fan is 12VDC 0.55A, probalby SP140L, the model number is 31-002574. I could't find a datasheet.
Here is my schematic:
EDIT3: Okay my schematics are actually wrong, I edited it to the right one. I am also using an NPN transistor and mosfet, that was also wrong in my post, sorry!
I tried making a soft start with an NTC but the problem is the NTC holds its resistance for longer, so if I were to turn off the fan and turn it on again in a short time it would still have this behavior. is there any other way to do this really simple but have it soft start every time?
I did it in software by not turning on the mosfet 100% and slowly increasing it to 100%, its working but the fan is making strange noises then.