Datasheet

13© KEMET Electronics Corporation • P.O. Box 5928 • Greenville, SC 29606 • 864-963-6300 • www.kemet.com A4069_A758 • 8/29/2017
Single-Ended Conductive Polymer Aluminum Solid Electrolytic Capacitors
A758 105°C
Anode foil
Cathode foil
T i ssu e s
Foil tabs
Slitting
Winding
Welding
Forming
Marking
Assembling
Aging
Inspection
Packing
Construction Data
The manufacturing process begins with the anode foil being
electrochemically etched to increase the surface area and
then ‘formed’ to produce the aluminum oxide layer. Both the
anode and cathode foils are then interleaved with absorbent
paper and wound into a cylinder. During the winding process,
aluminum tabs are attached to each foil to provide the
electrical contact.
The deck, complete with terminals, is attached to the tabs
and then folded down to rest on top of the winding. The
complete winding is impregnated with a conductive polymer
electrolyte before being housed in a suitable container, usually
an aluminum can, and sealed. Throughout the process, all
materials inside the housing must be maintained at the
highest purity and be compatible with the electrolyte.
Each capacitor is aged and tested before being packed.
The purpose of aging is to repair any damage in the oxide
layer and thus reduce the leakage current to a very low level.
Aging is normally carried out at the rated temperature of the
capacitor and is accomplished by applying voltage to the
device while carefully controlling the supply current. The
process may take several hours to complete. Damage to the
oxide layer can occur due to variety of reasons:
• Slitting of the anode foil after forming
• Attaching the tabs to the anode foil
• Minor mechanical damage caused during winding