These were salvaged from hundreds of older used church audio receiving
equipment.
This PCB is the power supply that also acts as the charger for the included
7.2v 2000 mAh Lithium Ion battery pack. It works as a standalone charger.
Just connect 12v to the wires, and it will charge the pack.
The PCB also has a 15 pin connector on the bottom to power the unit's
mainboard. We do not know the pinout, but its probably trivial to figure it
out.
The pack we tested still seems to hold a charge. However, many may be
completely bad as they have been sitting around a long time without being
recharged. We cannot stand behind these batteries!
We disassembled a pack, and found 2x Panasonic CGR18650A cells inside, but
manufacturer may vary.
These would make great onboard chargers for a variety of electronics projects!