Steve,
It is Chernobyl! 0.6A into a 1.3AH NiCd pack.
Debating about doubling it to 2.6AH.
I always had great luck with keeping the charging amps low, like C/10 ~ C/5.
But it is solar, so it will not be like someone throws a switch and sends 600ma into the NiCds.
Current will increase as the sun comes up.
And because of where the Vmp is, in relation to the max battery voltage, the charging current should drop quite fast as the battery voltage increases. Sort of the same idea as those "self regulating" 12V 30-cell solar panels that didn't work for crap on FLAs? LOL
"the schottky between the alkalines and the rail would prematurely load your D cells"...
Not with my math. Thats where 'After everything gets "
Broken In"...' comes in.
I went with 1.2V for the NiCds, or a hair less.
The alkalines won't stay at 1.63V very long. I went with 1.5V and less.
Should keep the NiCds around 1.1V min. I don't like taking them lower than that because it seems to me it takes more power (relatively, like it needs more AH in than it should [never charted it with a computer, just observations over the years]) to get them recharged if they get down to say 1.0 or less.
Norm,
It really won't be switching back and forth between packs.
When the NiCds are low, the alalines will start supplying part of the LED curent.
The 2 packs will share the load.
It would be a GREAT place for a tiny WT.
Not a project I want to get involved in now.
Time, parts cost, welder-less garage, etc.
Something else might be added too.
An idiot light.
Crazy bright red LED with a 10K resistor right above the padlock would be enough to let whoever locks up the shed at night (usually midnight to 2:30AM) to remember to shut the lights off!
"Gosh. It is pitch black out here. Whats that red light 2" above my fingers?"They'd forget to turn them off 3~4 days a week, and since they are not designed to be very bright, in the morning the guy who opens it (admittedly, that is usually me) may not notice they are on.
G-