The memory effect was first described in the 1960s by NASA. Sintered NiCd batteries in satellites have been charged regardless of the degree of discharge on a regular basis, ie at each orbit around the sun through solar cells. Over time, the batteries fit in the charging rhythm; their capacity reached only until the next charging cycle, although it was significantly larger in size.
The Memory Healer program
The memory effect is most likely due to two processes.

Crystal formation. During charging of NiCd batteries are cadmium microcrystals form [1] If the battery is discharged only to a certain "over the charge cycles consistent" level, this favors the formation of larger crystals of microcrystals in undischarged areas. Because the larger with the same mass have a smaller total surface area in comparison with smaller crystals, they react when unloading bad, why the voltage collapses.
Recrystallization: Senior charging technologies ignore the battery level. Invite you for a specified period of time and only charge a partially discharged battery. This results in recrystallization of the Cd-electrode. Because of the position of the cadmium in the electrochemical series, the recrystallization is connected with a lower output voltage and a resulting lower capacitance.