Cheap light/ AA charger...

[Blackwolf]

   I was at the evil place that shall not be mentioned (Wal-De-Mart) the other day and found some single unit landscape lights for four bucks each.  These are rated to power for 8 hrs after a full charge in the sun.  They put off a decent amount of light I would say at least as much as a small candle.
   I have been using them as nightlights and to get around the house at night when I don't need full light.  i opened one up the other day to check into modding it to have an on/off switch instead of the light sensor (which will be easy to do) and found that they use a cheap AA NiCad as the power source. 
   This means they could also be used to charge better grade AA rechargeables such as NiCads making the light better or just using it as a charger for the AAs to be used in other devices such as my Garmin GPS, cell phone backup power pack, two way radios, Mag light etc.  they are small, lightweight and could be further modified to fit other situations such as a backpak top array to charge several AAs by day to have some camp light at night and run your small equipment.
    I know there are other units out there that can be canibalized for these purposes but these are the cheapest I have seen so far and would be great for experimenting before buying a better unit to modify.

Just a heads up for those interested, keep up the great post, I love the ideas here they are right up my alley.
Sincerely, Blackwolf

[ken]

Thanks for your post....I too cannibalize solar yard lights for their panel.  I try to buy the yard lights on sale or the damaged sets that are marked way down.

I like the yard lights with rectangular panels as they seem easier to get at, your experience may be different. 

After removing the yard lights guts, I epoxy individual AA, or AAA cell holders directly to the back of the panel.  Individual battery cell holders are required because you want to charge them in parallel, not series.  Connect all the red (positive) battery holder leads together and solder them to the panels positive terminal, next do the same for the negative (black) leads.  Presto you have a compact back-packable charger for emergency use.  By the way, 4 AA cell holders will fit the back of the panels perfectly (the ones i have), yours may be different.  I usually epoxy on 2 (AA) and 2 (AAA) holders on each panel to cover both battery sizes.

For  example, my last yard light solar panel produced over 200 milli-amp hours at about 2.3 volts.  A typical AA size NiMh battery will be rated at 2500-2600 milli-amp hours, so the charger will take some time to do recharge the batteries, say 3-4 days of good sun to recharge if completely dead.  I make these little cheap chargers to add to my smaller kits just to have another charging means.

For those of you that do not want to do anything,and still have an emergency battery charger, just remember this.  if the "lights go out", just utilize your yard lights as they are, no modification.  Just add batteries in the morning, allow them to charge through the day, and remove them at night, as easy as that, no modification required, and your wife will appreciate that you are not messing with the yard lights. 

happy yard light hunting