Datasheet

18© KEMET Electronics Corporation • KEMET Tower • One East Broward Boulevard A4001_EDK • 4/22/2019
Fort Lauderdale, FL 33301 USA • 954-766-2800 • www.kemet.com
Surface Mount Aluminum Electrolytic Capacitors – EDK, +85°C
Extended cathode
Anode foil
Cathode foil
Tissues
Foil tabs
Aging
Etching
Forming
Winding
Decking
Impregnation
Assembly
Testing
Sleeving
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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sleevedand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
Asamplefromeachbatchistakenbythequalitydepartmentafter
completionoftheproductionprocess.Thissamplesizeiscontrolled
bytheuseofrecognizedsamplingtablesdenedinBS6001.
Thefollowingtestsareappliedandmaybevariedattherequest
ofthecustomer.Inthiscasethebatch,orspecialprocedure,will
determinethecourseofaction.
Electrical:
• Leakage current
• Capacitance
• ESR
 •Impedance
• Tan Delta
Mechanical/Visual:
• Overall dimensions
• Torque test of mounting stud
• Print detail
• Box labels
• Packaging, including packed
quantity