Solar powered landscape lights - old scanner batteries
I have some solar powered landscape lights around my yard. They come with some pretty lousy AA nicads installed. When the AA rechargeables I use in my handheld scanners start to get weak I put them in the yardlights. If I have plenty I tape two batteries side by side with the polarities reversed and use a piece of foil to put them in series.
Oops. i could have been more clear. When i said "start to get weak" I meant wouldn't hold a charge long enough for me to listen to the radio for many hours. The batteries were still better than what was in the solar lights and I replaced the POS 300 mah batteries in the light with old 2500 mah batteries that had been in the scanner.