Somewhat off topic, but I'm hoping someone can help. I'm building a solar powered weather station and plan to use 1 or 2 18650 cells. There are tons of small solar chargers available for these, however they all charge the cells to ~4.2V. To maximize life from the LiIon batteries I'd like to keep them between 40-80% charged.
So what I'm looking for is either a solar module that I can set to only charge the cells to ~3.9V or a way to make a 4.2V charger work. Since I'm not having any luck finding 3.9V chargers what I've been thinking about is perhaps using a schottky diode to drop the 4.2V to around 3.9V. however that would prevent the charger from seeing voltage from the battery and it might not start charging. So I'm thinking maybe putting a 100 ohm resistor in parrel with the diode, that would allow the charger to see the battery voltage. I still have to figure out how much current the microcontrollers, etc. will draw, but it's going to be at least 10 mA when idle, with bursts up to several hundred ma when transmitting. Does this sound like a reasonable plan? Any better suggestions? Thanks, Pete. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20200602/3cd29a40/attachment.html> _______________________________________________ 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)
