I am trying to design a circuit and was wondering how to design it that the 12V 800mAH NimH battery I am using will not overcharge. I have researched trickle charging and as far as I understand, a zener diode that regulates the voltage down to about 13.3-13.7V should do. I chose a 14V Zener, taking into account the .6-.7V drop.
I have heard that trickle charging is not the best for the battery, but am not sure how much more work designing a smart charger would take.
I was also thinking of using another diode to prevent flow back to the panels from the battery.
I was wondering if I needed any additional components if I were to use three 5.5V solar cells in parallel outputting 40mA (16.5V total at 40mA, regulated to 13.3V by the zener) in order to prevent overcharging.
A similar question to mine was asked at How do I avoid overcharging a battery? However, this dealt more with a larger lead-acid battery and used a voltage regulator with a schottky diode.
Smart charging circuit for NiMH battery pack This link discusses almost my exact same question, but I was confused to the answer given which said that up to 1.45V per cell could be charged, taking my max charge voltage up to 14.5V.
Considering I am only outputting 40mA to an 800mAH battery, it seems that I may not need any more battery protection, but would love any input.