I'll be using it to recharge 9v batteries.
What I want to know is:
What would the optimum charge current/voltage be?
Should I pulse the charge current?
How do I detect the state of charge?
How can I get ~1.6v from the arduino to charge an AA? Can I use PWM 5v?
And any other useful info you may want to add.
I have a ton of parts/shields/etc for arduino as well as components.
LCD's, IC's, LEDs, diodes, resistors, crystals, etc.
Would also like to do a battery diagnostic utility to test health, resistance, charge, etc.
Can anyone help?
EDIT: So I made a quick circuit and sketch to charge an AA battery to 1.6v, using an LM317 adjustable voltage regulator. As os so far, it is working.
Now I need to figure out how to make a voltage doubler. I'm thinking something like 40-50 mA output at 10v.
I have an LM324N quad op amp chip as well as one of these. How could I make a doubler circuit?