I'm trying to understand which voltage I need to charge my NiMH batteries so I can purchase the components to do this.
Actually I have 2x AA Ni-MH 1.2 V 1900 mAh and 4x Solar Panel 2 V 220 mA (0.44 W).
I read Solar Cell - Preventing overcharge of an NiMH battery and Voltage input for charging NiMH Batteries but I'm still confused as I'm not an expert in this field.
I gathered this information:
- Batteries should not drop under 1 V or they will be damage also not go over 1.78 V;
- Constant voltage doesn't work to recharge them (not sure).
I checked out some components to stabilize the current and I found a LM317 in order to stabilize the current to (C/10) 200 mAh and use a MAX471 to check out these values.
But the problem will be the voltage that during the day will drop or go up due to weather so the voltage will never be stable, it is a positive thing?
In the case I need a stable voltage I also found these components (M2578A, TL497A).
I hope to find somebody that can help me. I'm free to other solutions if this one doesn't fit my purpose.