Another very important note; diodes don't drop voltage the same at all current levels. Meaning; they will NOT stop your 4.5V panel from overcharging your battery to 4.5V if you don't have a dedicated charging IC.
If you want to charge your battery to an unusual voltage, I highly recommend using an adjustable CC/CV (constant-current/constant-voltage) buck converter. They're widely available from China on eBay and Aliexpress, and probably available from the US through Amazon. This way you can set a safe current limit (say 400mA), and a voltage limit that is lower than 4.2V (say 3.9 or 4.0V). Then you could even use multiple panels in series and not worry about charging, the input limit for the common LM2596 modules is 35V. Here's some data for a common 1N5819 Schottky diode illustrating the issue of voltage drop as current tapers down at the end of charging: 1.0A - 0.41V 0.5A - 0.35V 0.1A - 0.28V 20mA - 0.23V -- Sent from: http://electric-vehicle-discussion-list.413529.n4.nabble.com/ _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub ARCHIVE: http://www.evdl.org/archive/index.html INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)
