I purchased the following solar security light kit a few weeks ago:
Mounted system, worked great. FYI, the lamp uses a 6V, 900mAh, NiCd battery pack that is recharged with the included solar panel. I'm presuming that the controller is integral to the lamp assy, but I could be wrong (i.e. said controller may be integrated into the solar panel assy).
Well, we had a hail storm last week that totally destroyed the solar panel.
I have verified that it is NOT possible to purchase the solar panel separately, so I am considering the following scheme:
Purchase another security light kit – same model as the original purchase. I'd now have one solar panel assy and two lamp assy's. Next, I'd attach the two lamp assy's to the solar panel assy using a dc power splitter cord. Now, I'd have both lamp assy's wired in parallel.
My questions: Would this charge both batteries? I'm presuming that a larger recharging current would be routed to the battery with the lowest open circuit voltage. If the controller is mounted in the lamp, I'll have two controllers downstream of the cable split. If the controller is mounted in the solar panel component, I'll have one controller upstream of the cable split. Does it matter where the controller is mounted (see above)?
Best Answer
These things are the dumbest solar charge circuits possible. See a tear down here https://youtu.be/OSR2ofEAJKg
Solar cell to reverse protection diode to 6x series AA NiCD battery pack. No charge controller. It depends on the battery pack getting trickled charged, and being stronger than the solar panel.
Connecting the same panel to two lights will cut the current to both, and likely tripling the charge time (it won't be exactly half). The built in diodes on the input board will prevent one battery from charging the other, just as they prevent the battery from back feeding the solar panel in normal use. No modification or precautions needed.
These lights will already deep discharge the batteries over night as is, which is why NiCD are chosen. Their runtime will be reduced due to less power charging them.
FYI you can buy similar panels from overseas online for a few bucks. Probably from the same place HF gets theirs.