This charger is an investment in the health of your rechargeable batteries. Lets make real discharge / charge cycles to maintain their autonomy in time. I managed to resurrect a battery that was however not detected by this charger. One tip is: disconnected charger (very important), put a stack detected and undetected in two side by side slots battery. Connect the terminals + 2 together with a paper clip, all for about fifteen seconds. It'll put just enough current in the unrecognized battery for it one. And from there, it may resume its load. Small flat to not put a 5/5. The operation of the buttons is not super intuitive to change charging mode. Remember to read the user manual.
