Charging 1 2v Nimh Batteries With A 2 Watt Solar Panel

My circuit to power a red led require 1 8v so i have to connect the batteries in series in order to light the led.

Charging 1 2v nimh batteries with a 2 watt solar panel.

The solar panel is rated at 1 w with a max load voltage of 6 4 v and the product page is here. The battery capacity is 2450 mah with a nominal 1 2 v per cell and the datasheet is here. I have 2 nimh aa batteries 1 2v 2050mah 1 solar panel at 2v 0 3w generating 150mah. I am working on a school project involving charging 4 aaa nimh batteries 1 2v each with a small solar panel used for outside lighting.

A 2v solar cell would be more appropriate for charging a single rechargeable battery. It varies from 3 2 v to 3 7 v ni mh is 1 2 v and nicd is also 1 2 v. The solar panel being used is a 12v 40ma solar panel. I actually tested the panel myself and found that in the best case with 90 000 lux full sun the max voltage was 5 2 v corresponding to a max current of 157 ma.

That thing i already understand the problem is that i can t charge the 2 batteries with the solar panel while the batteries are in series as. To charge a battery with a solar panel connect a charge connector to the solar panel. With the standard 0 7v drop of a diode you ll have 1 3v of charge voltage which won t be high enough for a maximum charge but a schottky rectifier diode selected for 0 5v forward voltage drop would get you 1 5v charging. Let s eliminate the lithium ion because its nominal voltage is over twice the voltage of aa or aaa batteries.

Then run wires from the battery to the charge connector making sure to match the positive and negative poles. Because most consumer devices use either internal batteries aa or aaa batteries.