Reply to thread

Your solar cell is your sensor. You want to charge

when "lit" and when charge fails, throw current

onto LEDs instead. That could be something

simple like a reed relay with the LED hanging

off the NC terminal (C=batt, coil from cells to gnd).

Low current coil ought to be tolerable loss (10mA

from ~ 1A cell current?). Blocking Schottky from

cells to battery, and a battery that likes repetitive

overcharging and deep discharge both.