May 2011

Ni-Cd block batteryTechnical manual

1. Introduction 3

2. Benefitsoftheblockbattery 4 2.1Completereliability 4 2.2Longcyclelife 4 2.3Exceptionallylonglifetime 4 2.4Lowmaintenance 4 2.5Wideoperatingtemperaturerange 4 2.6Fastrecharge 4 2.7Resistancetomechanicalabuse 4 2.8Highresistancetoelectricalabuse 4 2.9Simpleinstallation 4 2.10Extendedstorage 4 2.11Well-provenpocketplateconstruction 4 2.12Environmentallysafe 4 2.13Lowlife-cyclecost 4

3. Electrochemistryofnickel-cadmiumbatteries5

4. Constructionfeaturesoftheblockbattery6 4.1Plateassembly 7 4.2Separation 8 4.3Electrolyte 8 4.4Terminalpillars 9 4.5Ventingsystem 9 4.6Cellcontainer 9

5. Batterytypesandapplications 10 5.1TypeL 11 5.2TypeM 11 5.3TypeH 11 5.4Choiceoftype 11

6. Operatingfeatures 12 6.1Capacity 12 6.2Cellvoltage 12 6.3Internalresistance 12 6.4Effectoftemperatureonperformance 13 6.5Short-circuitvalues 14 6.6Opencircuitloss 14 6.7Cycling 14 6.8Effectoftemperatureonlifetime 15 6.9Waterconsumptionandgasevolution 16

7. Batterysizingprinciples instationarystandbyapplications 17 7.1Thevoltagewindow 17 7.2Dischargeprofile 17 7.3Temperature 17 7.4Stateofchargeorrechargetime 18 7.5Ageing 18 7.6Floatingeffect 18

8. Batterycharging 19 8.1Charginggeneralities 19 8.2Constantvoltagechargingmethods 19 8.3Chargeacceptance 20 8.4Chargeefficiency 22 8.5Temperatureeffects 22 8.6Commissioning 22

9. Specialoperatingfactors 23 9.1Electricalabuse 23 9.2Mechanicalabuse 23

10.Installationandoperatinginstructions 24 10.1Receivingtheshipment 24 10.2Storage 24 10.3Electrolyte/celloil 25 10.4Installation 25 10.5Commissioning 25 10.6Charginginservice 26 10.7Periodicmaintenance 27 10.8Changingelectrolyte 27

11.Maintenanceofblockbatteriesinservice28 11.1Cleanliness/mechanical 28 11.2Topping-up 28 11.3Capacitycheck 29 11.4Recommendedmaintenanceprocedure29

12.Disposalandrecycling 30

Contents

1.Introduction

Thenickel-cadmiumbatteryisthemostreliablebatterysystemavailableinthemarkettoday.Itsuniquefeaturesenableittobeusedinapplicationsandenvironmentsuntenableforotherwidelyavailablebatterysystems.

Itisnotsurprising,therefore,thatthenickel-cadmiumbatteryhasbecomeanobviousfirstchoiceforuserslookingforareliable,longlife,lowmaintenancesystem.

This manual details the design and operating characteristics of the Saft Nife pocket plate block battery to enable a successful battery system to be achieved. A battery which, while retaining all the advantages arising from nearly 100 years of development of the pocket plate technology, can be so worry free that its only major maintenance requirement is topping-up with water.

3

2.1 Complete reliabilityTheblockbatterydoesnotsufferfromthesuddendeathfailureassociatedwiththeleadacidbattery(seesection4.1Plateassembly).

2.2 Long cycle lifeTheblockbatteryhasalongcyclelifeevenwhenthecharge/dischargecycleinvolves100%depthofdischarge(seesection6.7Cycling).

2.3 Exceptionally long lifetimeAlifetimeinexcessoftwentyyearsisachievedbytheSaftNifeblockbatteryinmanyapplications,andatelevatedtemperaturesithasalifetimeunthinkableforotherwidelyavailablebatterytechnologies(seesection6.8Effectoftemperatureonlifetime).

2.4 Low maintenanceWithitsgenerouselectrolytereserve,theblockbatteryreducestheneedfortopping-upwithwater,andcanbeleftinremotesitesforlongperiodswithoutanymaintenance(seesection6.9Waterconsumptionandgasevolution).

2.5 Wide operating temperature rangeTheblockbatteryhasanelectrolytewhichallowsittohaveanormaloperatingtemperatureoffrom–20°Cto+50°C(–4°Fto

+122°F),andacceptextremetemperatures,rangingfromaslowas–50°C(–58°F)toupto+70°C(+158°F)(seesection4.3Electrolyte).

2.6 Fast rechargeTheblockbatterycanberechargedatcurrentswhichallowveryfastrechargetimestobeachieved(seesection8.3Chargeacceptance).

2.7 Resistance to mechanical abuseTheblockbatteryisdesignedtohavethemechanicalstrengthrequiredtowithstandalltheharshtreatmentassociatedwithtransportationoverdifficultterrain(seesection9.2Mechanicalabuse).

2.8 High resistance to electrical abuseTheblockbatterywillsurviveabusewhichwoulddestroyaleadacidbattery,forexampleovercharging,deepdischarging,andhighripplecurrents(seesection9.1Electricalabuse).

2.9 Simple installationTheblockbatterycanbeusedwithawiderangeofstationaryandmobileapplicationsasitproducesnocorrosivevapors,usescorrosion-freepolypropylenecontainersandhasasimpleboltedconnectorassemblysystem(seesection10Installationandoperatinginstructions).

2.10 Extended storageWhenstoredintheemptyanddischargedstateundertherecommendedconditions,theblockbatterycanbestoredformanyyears(seesection10.2Installationandoperatinginstructions).

2.11 Well-proven pocket plate constructionSafthasnearly100yearsofmanufacturingandapplicationexperiencewithrespecttothenickel-cadmiumpocketplateproduct,andthisexpertisehasbeenbuiltintothetwenty-plusyears’designlifeoftheblockbatteryproduct(seesection4Constructionfeaturesoftheblockbattery).

2.12 Environmentally safeSaftoperatesadedicatedrecyclingcentertorecoverthenickel,cadmium,steelandplasticusedinthebattery(seesection12Disposalandrecycling).

2.13 Low life-cycle costWhenallthefactorsoflifetime,lowmaintenancerequirements,simpleinstallationandstorageandresistancetoabusearetakenintoaccount,theSaftNifeblockbatterybecomesthemostcosteffectivesolutionformanyprofessionalapplications.

2.Benefitsofthe blockbattery

4

Thenickel-cadmiumbatteryusesnickelhydroxideastheactivematerialforthepositiveplate,andcadmiumhydroxideforthenegativeplate.

Theelectrolyteisanaqueoussolutionofpotassiumhydroxidecontainingsmallquantitiesoflithiumhydroxidetoimprovecyclelifeandhightemperatureoperation.

Theelectrolyteisonlyusedforiontransfer;itisnotchemicallychangedordegradedduringthecharge/dischargecycle.Inthecaseoftheleadacidbattery,thepositiveandnegativeactivematerialschemicallyreactwiththesulphuricacidelectrolyteresultinginanageingprocess.

Thesupportstructureofbothplatesissteel.Thisisunaffectedbytheelectrolyte,andretainsitsstrengththroughoutthelifeofthecell.Inthecaseoftheleadacidbattery,thebasicstructureofbothplatesisleadandleadoxidewhichplayapartintheelectrochemistryoftheprocessandarenaturallycorrodedduringthelifeofthebattery.

Thecharge/dischargereactionofanickel-cadmiumbatteryisasfollows:

Duringdischargethetrivalentnickelhydroxideisreducedtodivalentnickelhydroxide,andthecadmiumatthenegativeplateformscadmiumhydroxide.

Oncharge,thereversereactiontakesplaceuntilthecellpotentialrisestoalevelwherehydrogenisevolvedatthenegativeplateandoxygenatthepositiveplatewhichresultsinwaterloss.

Unliketheleadacidbattery,thereislittlechangeintheelectrolytedensityduringchargeanddischarge.Thisallowslargereservesofelectrolytetobeusedwithoutinconveniencetotheelectrochemistryofthecouple.

Thus,throughitselectrochemistry,thenickel-cadmiumbatteryhasamorestablebehaviorthantheleadacidbattery,givingitalongerlife,superiorcharacteristicsandagreaterresistanceagainstabusiveconditions.

Nickel-cadmiumcellshaveanominalvoltageof1.2V.

discharge2NiOOH+2H2O+Cd2Ni(OH)2+Cd(OH)2

charge

3.Electrochemistryof nickel-cadmiumbatteries

5

4. Constructionfeatures oftheblockbattery

6

CellcontainerMaterial: translucentpolypropylene.

PlategroupbusConnects the plate tabs with the terminal post. Plate tabs and terminal post are projection-welded to the plate group bus.

Thecellsareweldedtogethertoformruggedblocksof1-6cellsdependingonthecellsizeandtype.

PlatetabSpot-welded both to the plate side-frames and to the upper edge of the pocket plate.

SeparatinggridsSeparate the plates and insulate the plate frames from each other. The grids allow free circulation of electrolyte between the plates.

PlateHorizontal pocketsof double-perforatedsteel strips.

SaftcellsfulfillallrequirementsspecifiedbyIEC60623.

Flame-arrestingventsMaterial: polypropylene.

PlateframeSeals the plate pocketsand serves as a current collector.

Protectivecover•to prevent external

short-circuits• in line with

EN 50272-2 (safety) with IP2 level

4.1 Plate assemblyThenickel-cadmiumcellconsistsoftwogroupsofplates,thepositivecontainingnickelhydroxideandthenegativecontainingcadmiumhydroxide.

TheactivematerialsoftheSaftNifepocketplateblockbatteryareretainedinpocketsformedfromsteelstripsdouble-perforatedbyapatentedprocess.

Thesepocketsaremechanicallylinkedtogether,cuttothesizecorrespondingtotheplatewidthandcompressedtothefinalplatedimension.Thisprocessleadstoaplatewhichisnotonlymechanicallyverystrongbutalsoretainsitsactivematerialwithinasteelcontainmentwhichpromotesconductivityandminimizeselectrodeswelling.Theseplatesarethenweldedtoacurrentcarryingbusbarassemblywhichfurtherensuresthemechanicalandelectricalstabilityoftheproduct.

Nickel-cadmiumbatterieshaveanexceptionallygoodlifetimeandcyclelifebecausetheirplatesarenotgraduallyweakenedbycorrosion,asthestructuralcomponentoftheplateissteel.Theactivematerialoftheplateisnotstructural,onlyelectrical.Thealkalineelectrolytedoesnotreactwithsteel,whichmeansthatthesupportingstructureoftheblockbatterystaysintactandunchangedforthelifeofthebattery.Thereisnocorrosionandnoriskof“suddendeath.”

Incontrast,theleadplateofaleadacidbatteryisboththestructureandtheactivematerialandthisleadstosheddingofthepositiveplatematerialandeventualstructuralcollapse.

7

4.2 SeparationSeparationbetweenplatesisprovidedbyinjectionmoldedplasticseparatorgrids,integratingbothplateedgeinsulationandplateseparation.

Byprovidingalargespacingbetweenthepositiveandnegativeplatesandagenerousquantityofelectrolytebetweenplates,goodelectrolytecirculationandgasdissipationareprovided,andthereisnostratificationoftheelectrolyteasfoundwithleadacidbatteries.

4.3 ElectrolyteTheelectrolyteusedintheblockbattery,whichisasolutionofpotassiumhydroxideandlithiumhydroxide,isoptimizedtogivethebestcombinationofperformance,life,energyefficiencyandawidetemperaturerange.

Theconcentrationofthestandardelectrolyteissuchastoallowthecelltobeoperatedtotemperatureextremesaslowas–20°C(–4°F)andashighas+50°C(+122°F).Thisallowstheveryhightemperaturefluctuationfoundincertainregionstobeaccommodated.

Forverylowtemperaturesaspecialhighdensityelectrolytecanbeused.

Theelectrodematerialislessreactivewiththealkalineelectrolyte(nickel-cadmiumsecondarybatteries)thanwithacidelectrolytes(leadacidsecondarybatteries).Furthermore,duringcharginganddischarginginalkalinebatteriestheelectrolyteworksmainlyasacarrierofoxygenorhydroxylionsfromoneelectrodetotheother;hencethecompositionortheconcentrationoftheelectrolytedoesnotchangenoticeably.Inthecharge/dischargereactionof

thenickel-cadmiumbattery,thepotassiumhydroxideisnotmentionedinthereactionformula.Asmallamountofwaterisproducedduringthechargingprocedure(andconsumedduringthedischarge).Theamountisnotenoughtomakeitpossibletodetectifthebatteryischargedordischargedbymeasuringthedensityoftheelectrolyte.

Oncethebatteryhasbeenfilledwiththecorrectelectrolyteeitheratthebatteryfactoryorduringthebatterycommissioningthereisnoneedtochecktheelectrolytedensityperiodically.Thedensityoftheelectrolyteinthebatteryeitherincreasesordecreasesastheelectrolyteleveldropsbecauseofwaterelectrolysisorevaporationorrisesattopping-up.Interpretationofdensitymeasurementsisdifficultandcouldbemisleading.

8

Inmostapplicationstheelectrolytewillretainitseffectivenessforthelifeofthebatteryandwillneverneedreplacing.However,undercertainconditions,suchasextendeduseinhightemperaturesituations,theelectrolytecanbecomecarbonated.Ifthisoccursthebatteryperformancecanbeimprovedbyreplacingtheelectrolyte.

ThestandardelectrolyteusedforthefirstfillincellsisE22andforreplacementinserviceisE13.

4.4 Terminal pillarsShortterminalpillarsareweldedtotheplatebusbarsusingawell-establishedandprovenmethod.Thesepostsaremanufacturedfromsteelbar,internallythreadedforboltingonconnectors,andnickel-plated.

Thesealingbetweenthecoverandtheterminalisprovidedbyacompressedvisco-elasticsealingsurfaceheldinplacebycompressionlockwashers.Thisassemblyisdesignedtoprovidesatisfactorysealingthroughoutthelifeoftheproduct.

4.5 Venting systemTheblockbatteryisfittedwithaspecialflame-arrestingflip-topventtogiveaneffectiveandsafeventingsystem.

4.6 Cell containerThebatteryisbuiltupusingwell-provenblockbatteryconstruction.Thetoughpolypropylenecontainersareweldedtogetherbyheatsealing.

Theblockbatteryuses4platesizesorplatemodules.Thesearedesignatedmoduletype1,2,3and4.Theycanberecognizedfromtheblockdimensionsasfollows:

9

Table1-Correlationbetweenblockdimensionsandplatemodulenumber

Blockwidth(mm) Blockheight(mm) Platemodule

123 194 1

123 264 2

195 349 3

195 405 4

5.Batterytypesandapplications

10

Inordertoprovideanoptimumsolutionforthewiderangeofbatteryapplicationswhichexist,the

blockbatteryisconstructedinthreeperformanceranges.

SaftNife batterytypes L M H

Autonomymini 3h 30min 1s maxi 100h 3h 30min Power Power Starting, backup backup PowerUseofbattery

Bulkenergy backup storage Applications Enginestarting-Switchgear-UPS-Processcontrol- Dataandinformationsystems-Emergencylighting- Securityandfirealarmsystems- Switchingandtransmissionsystems-Signaling Railways intercity& l l l urbantransport Stationary Utilities electricity,gas, waterproduction l l l

&distribution Oilandgas offshore&onshore, petrochemical l l l

refineries Industry chemical,mining, l l l steelmetalworks Buildings public,private l l l

Medical hospitals, l l l X-rayequipment Telecom radio, satellite,cable, l l repeaterstations, cellularbasestations Railroad substations l l l &signaling Airports l l l Military allapplications l l l

11

5.1 Type LTheLtypeisdesignedforapplicationswherethebatteryisrequiredtoprovideareliablesourceofenergyoverrelativelylongdischargeperiods.Normally,thecurrentisrelativelylowincomparisonwiththetotalstoredenergy,andthedischargesaregenerallyinfrequent.Typicalusesarepowerbackupandbulkenergystorage.

5.2 Type MTheMtypeisdesignedforapplicationswherethebatteriesareusuallyrequiredtosustainelectricalloadsforbetween30minutesto3hoursorfor“mixed”loadswhichinvolveamixtureofhighandlowdischargerates.Theapplicationscanhavefrequentorinfrequentdischarges.Therangeistypicallyusedinpowerbackupapplications.

5.3 Type HTheHtypeisdesignedforapplicationswherethereisademandforarelativelyhighcurrentovershortperiods,usuallylessthan30minutesinduration.Theapplicationscanhavefrequentorinfrequentdischarges.Therangeistypicallyusedinstartingandpowerbackupapplications.

5.4 Choice of typeInperformancetermstherangescoverthefulltimespectrumfromrapidhighcurrentdischargesofasecondtoverylonglowcurrentdischargesofmanyhours.Table2showsingeneraltermsthesplitbetweentherangesforthedifferentdischargetypes.Thechoiceisrelatedtothedischargetimeandtheendofdischargevoltage.Thereare,ofcourse,manyapplicationswheretherearemultipledischarges,andsotheoptimumrangetypeshouldbecalculated.Thisisexplainedinthesection7“Batterysizing”.

Table2-Generalselectionofcellrange

6.1 CapacityTheblockbatterycapacityisratedinampere-hours(Ah)andisthequantityofelectricityat+20°C(+68°F)whichitcansupplyfora5hourdischargeto1.0Vafterbeingfullychargedfor7.5hoursat0.2C5A.ThisfigureconformstotheIEC60623standard.

AccordingtotheIEC60623(Edition4),0.2C5Aisalsoexpressedas0.2I tA.Thereferencetestcurrent(I t)isexpressedas: CnAh 1hwhere:Cn istheratedcapacity declaredbythe manufacturerinampere- hours(Ah), and

n isthetimebaseinhours(h) forwhichtheratedcapacity isdeclared.

6.2 Cell voltageThecellvoltageofnickel-cadmiumcellsresultsfromtheelectrochemicalpotentialsofthenickelandthecadmiumactivematerialsinthepresenceofthepotassiumhydroxideelectrolyte.Thenominalvoltageforthiselectrochemicalcoupleis1.2V.

6.3 Internal resistanceTheinternalresistanceofacellvarieswiththetemperatureandthestateofchargeandis,therefore,difficulttodefineandmeasureaccurately.

Themostpracticalvaluefornormalapplicationsisthedischargevoltageresponsetoachangeindischargecurrent.

TheinternalresistanceofablockbatterycelldependsontheperformancetypeandatnormaltemperaturehasthevaluesgiveninTable3inmΩper1/C5.

Toobtaintheinternalresistanceofacellitisnecessarytodividethevaluefromthetablebytheratedcapacity.

Forexample,theinternalresistanceofaSBH118(moduletype3)isgivenby: 39

=0.33mΩ 118ThefiguresofTable3areforfullychargedcells.

Forlowerstatesofchargethevaluesincrease.Forcells50%dischargedtheinternalresistanceisabout20%higher,andwhen90%discharged,itisabout80%higher.Theinternalresistanceofafullydischargedcellhasverylittlemeaning.

Reducingthetemperaturealsoincreasestheinternalresistance,andat0°C(+32°F),theinternalresistanceisabout40%higher.

Table3-InternalresistanceinmΩper1/C5

*TheinternalresistancesfortheSBLErangeareincludedinthecommercialdatabrochure.

Celltype Moduleplatesize(seetable1)

1 2 3 4

SBL* 84 105 123 142

SBM 55 62 78 86

SBH N/A 30 39 43

6.Operatingfeatures

I tA=

12

6.4 Effect of temperature on performanceVariationsinambienttemperatureaffecttheperformanceofthecellandthisneedstobetakenintoaccountwhensizingthebattery.

Lowtemperatureoperationhastheeffectofreducingtheperformance,butthehighertemperaturecharacteristicsaresimilartothoseatnormaltemperatures.Theeffectoflowtemperatureismoremarkedathigherratesofdischarge.

ThefactorswhicharerequiredinsizingabatterytocompensatefortemperaturevariationsaregiveninagraphicalforminFigure1(a),Ltype,Figure1(b),MtypeandFigure1(c),Htypeforoperatingtemperaturesfrom–20°Cto+50°C(–4°Fto+122°F).

Figure1(a)-Temperaturede-ratingfactorsforLtypecell

13

Figure1(c)-Temperaturede-ratingfactorsforHtypecell

Figure1(b)-Temperaturede-ratingfactorsforMtypecell

6.5 Short-circuit valuesThetypicalshort-circuitvalueinamperesforablockbatterycellisapproximately9timestheampere-hourcapacityforanLtypeblock,16timestheampere-hourcapacityforanMtypeblockand28timestheampere-hourcapacityforanHtypeblock.

Theblockbatterywithconventionalboltedassemblyconnectionswillwithstandashort-circuitcurrentofthismagnitudeformanyminuteswithoutdamage.

6.6 Open circuit lossThestateofchargeoftheblockcellonopencircuitslowlydecreaseswithtimeduetoself-discharge.Inpracticethisdecreaseisrelativelyrapidduringthefirsttwoweeks,butthenstabilizestoabout2%permonthat+20°C(+68°F).

Theself-dischargecharacteristicsofanickel-cadmiumcellareaffectedbythetemperature.Atlowtemperatures,thechargeretentionisbetterthanatnormaltemperature,andsotheopencircuitlossisreduced.However,theself-dischargeissignificantlyincreasedathighertemperatures.

ThetypicalopencircuitlossfortheblockbatteryforarangeoftemperatureswhichmaybeexperiencedinastationaryapplicationisshowninFigure2.

6.7 CyclingTheblockbatteryisdesignedtowithstandthewiderangeofcyclingbehaviorencounteredinstationaryapplications.Thiscanvaryfromlowdepthofdischargestodischargesofupto100%andthenumberofcyclesthattheproductwillbeabletoprovidewilldependonthedepthofdischarge.

Thelessdeeplyabatteryiscycled,thegreaterthenumberofcyclesitiscapableofperformingbeforeitis

unabletoachievetheminimumdesignlimit.Ashallowcyclewillgivemanythousandsofoperations,whereasadeepcyclewillgiveonlyhundredsofoperations.

Figure3givestypicalvaluesfortheeffectofdepthofdischargeontheavailablecyclelife,anditisclearthatwhensizingthebatteryforacyclingapplication,thenumberanddepthofcycleshaveanimportantconsequenceonthepredictedlifeofthesystem.

Figure2-Capacitylossonopencircuitstand

Figure3-Typicalcyclelifeversusdepthofdischarge

14

6.8 Effect of temperature on lifetimeTheblockbatteryisdesignedasatwentyyearlifeproduct,butaswitheverybatterysystem,increasingtemperaturereducestheexpectedlife.However,thereductioninlifetimewithincreasingtemperatureisverymuchlowerforthenickel-cadmiumbatterythantheleadacidbattery.

Thereductioninlifetimeforthenickel-cadmiumbattery,andforcomparison,ahighqualityleadacidbatteryisshowngraphicallyinFigure4.ThevaluesfortheleadacidbatteryareassuppliedbytheindustryandfoundinEurobatandIEEEdocumentation.

Ingeneralterms,forevery9ºC(16.2ºF)increaseintemperatureoverthenormaloperatingtemperatureof+25°C(+77°F),thereductioninservicelifeforanickel-cadmiumbatterywillbe20%,andforaleadacidbatterywillbe50%.

Inhightemperaturesituations,therefore,specialconsiderationmustbegiventodimensioningthenickel-cadmiumbattery.Underthesameconditions,theleadacidbatteryisnotapracticalproposition,duetoitsveryshortlifetime.TheVRLAbattery,forexample,whichhasalifetimeofabout7yearsundergoodconditions,hasthisreducedtolessthan1year,ifusedat+50°C(+122°F).

Figure4-Effectoftemperatureonlifetime

15

6.9 Water consumption and gas evolutionDuringcharging,moreampere-hoursaresuppliedtothebatterythanthecapacityavailablefordischarge.Theseadditionalampere-hoursmustbeprovidedtoreturnthebatterytothefullychargedstateand,sincetheyarenotallretainedbythecellanddonotallcontributedirectlytothechemicalchangestotheactivematerialsintheplates,theymustbedissipatedinsomeway.Thissurpluscharge,orovercharge,breaksdownthewatercontentoftheelectrolyteintooxygenandhydrogen,andpuredistilledordeionizedwaterhastobeaddedtoreplacethisloss.

Waterlossisassociatedwiththecurrentusedforovercharging.Abatterywhichisconstantlycycled,i.e.ischargedanddischargedonaregularbasis,willconsumemorewaterthanabatteryonstandbyoperation.

Intheory,thequantityofwaterusedcanbefoundbytheFaradicequationthateachampere-hourofoverchargebreaksdown0.366cm3ofwater.However,inpractice,thewaterusagewillbelessthanthis,astheoverchargecurrentisalsoneededtocounteractself-dischargeoftheelectrodes.

Theoverchargecurrentisafunctionofbothvoltageandtemperature,sobothhaveaninfluenceontheconsumptionofwater.Figure5givestypicalwaterconsumptionvaluesoverarangeofvoltagesfordifferentcelltypes.

Example:AnSBM161isfloatingat1.43V/cell.Theelectrolytereserveforthiscellis500cm3.FromFigure5,anMtypecellat1.43V/cellwilluse0.27cm3/monthforoneAhofcapacity.ThusanSBM161willuse0.27x161=43.5cm3permonthandtheelectrolytereservewillbeusedin

500=11.5months.

Thegasevolutionisafunctionoftheamountofwaterelectrolyzedintohydrogenandoxygenandarepredominantlygivenoffattheendofthechargingperiod.Thebatterygivesoffnogasduringanormaldischarge.

Theelectrolysisof1cm3ofwaterproduces1865cm3ofgasmixtureandthisgasmixtureisintheproportionof2/3hydrogenand1/3oxygen.Thustheelectrolysisof1cm3ofwaterproduces1243cm3ofhydrogen.

Figure5-Waterconsumptionvaluesfordifferentvoltagesandcelltypes

43.5

16

Thereareanumberofmethodswhichareusedtosizenickel-cadmiumbatteriesforstandbyfloatingapplications.ThemethodemployedbySaftistheIEEE1115recommendationwhichisacceptedinternationally.Thismethodtakesintoaccountmultipledischarges,temperaturede-rating,performanceafterfloatingandthevoltagewindowavailableforthebattery.

Asignificantadvantageofthenickel-cadmiumbatterycomparedtoaleadacidbattery,isthatitcanbefullydischargedwithoutanyinconvenienceintermsoflifeorrecharge.Thus,toobtainthesmallestandleastcostlybattery,itisanadvantagetodischargethebatterytothelowestpracticalvalueinordertoobtainthemaximumenergyfromthebattery.

Theprinciplesizingparameterswhichareofinterestare:

7.1 The voltage windowThisisthemaximumvoltageandtheminimumvoltageatthebatteryterminalsacceptableforthesystem.Inbatteryterms,themaximumvoltagegivesthevoltagewhichisavailabletochargethebattery,andtheminimumvoltagegivesthelowestvoltageacceptabletothesystemtowhichthebatterycanbedischarged.Indischargingthenickel-cadmiumbattery,thecellvoltageshouldbetakenaslowaspossibleinordertofindthemosteconomicandefficientbattery.

7.2 Discharge profileThisistheelectricalperformancerequiredfromthebatteryfortheapplication.Itmaybeexpressedintermsofamperesforacertainduration,oritmaybeexpressedintermsofpower,inwattsorkW,foracertainduration.Therequirementmaybesimplyonedischargeormanydischargesofacomplexnature.

7.3 TemperatureThemaximumandminimumtemperaturesandthenormalambienttemperaturewillhaveaninfluenceonthesizingofthebattery.Theperformanceofabatterydecreaseswithdecreasingtemperatureandsizingatalowtemperatureincreasesthebatterysize.Temperaturede-ratingcurvesareproducedforallcelltypestoallowtheperformancetoberecalculated.

7. Batterysizingprinciplesinstationarystandbyapplications

17

7.4 State of charge or recharge timeSomeapplicationsmayrequirethatthebatteryshallgiveafulldutycycleafteracertaintimeafterthepreviousdischarge.Thefactorsusedforthiswilldependonthedepthofdischarge,therateofdischarge,andthechargevoltageandcurrent.Arequirementforahighstateofchargedoesnotjustifyahighchargevoltageiftheresultisahighendofdischargevoltage.

7.5 AgeingSomecustomersrequireavaluetobeaddedtoallowfortheageingofthebatteryoveritslifetime.Thismaybeavaluerequiredbythecustomer,forexample10%,oritmaybearequirementfromthecustomerthatavalueisusedwhichwillensuretheserviceofthebatteryduringitslifetime.Thevaluetobeusedwilldependonthedischargerateofthebatteryandtheconditionsunderwhichthedischargeiscarriedout.

7.6 Floating effectWhenanickel-cadmiumcellismaintainedatafixedfloatingvoltageoveraperiodoftime,thereisadecreaseinthevoltagelevelofthedischargecurve.Thiseffectbeginsafteroneweekandreachesitsmaximuminabout3months.Itcanonlybeeliminatedbyafulldischarge/chargecycle,anditcannotbeeliminatedbyaboostcharge.Itisthereforenecessarytotakethisintoaccountinanycalculationsconcerningbatteriesinfloatapplications.

Astheeffectofreducingthevoltagelevelistoreducetheautonomyofthebattery,theeffectcanbeconsideredasreducingtheperformanceofthebatteryandsoperformancedown-ratingfactorsareused.

18

8.1 Charging generalitiesTheblockbatterycanbechargedbyallnormalmethods.Generally,batteriesinparalleloperationwithchargerandloadarechargedwithconstantvoltage.Inoperationswherethebatteryischargedseparatelyfromtheload,chargingwithconstantcurrentordecliningcurrentispossible.High-ratechargingoroverchargingwillnotdamagethebattery,butexcessivechargingwillincreasewaterconsumptiontosomedegree.

8.2 Constant voltage charging methodsBatteriesinstationaryapplicationsarenormallychargedbyaconstantvoltagefloatsystemandthiscanbeoftwotypes:thetwo-ratetype,wherethereisaninitialconstantvoltagechargefollowedbyalowervoltagefloatingvoltage;orasingle-ratefloatingvoltage.

Thesinglevoltagechargerisnecessarilyacompromisebetweenavoltagehighenoughtogiveanacceptablechargetimeandlowenoughtogivealowwaterusage.Howeveritdoesgiveasimplercharging

systemandacceptsasmallervoltagewindowthanthetwo-ratecharger.

Thetwo-ratechargerhasaninitialhighvoltagestagetochargethebatteryfollowedbyalowervoltagemaintenancecharge.Thisallowsthebatterytobechargedquickly,andyet,havealowwaterconsumptionduetothelowmaintenancechargeorfloatvoltagelevel.

Thevaluesusedfortheblockbatteryrangesforsingleandtwo-ratechargesystemsareasshowninTable4below.

Tominimizethewaterusage,itisimportanttousealowchargevoltagepercell,andsotheminimumvoltageforthesinglelevelandthetwolevelchargevoltageisthenormallyrecommendedvalue.Thisalsohelpswithinavoltagewindowtoobtainthelowest,andmosteffective,endofdischargevoltagepercell(seesection7Batterysizing).

Thevaluesgivenasmaximumarethosewhichareacceptabletothebattery,butwouldnotnormallybeusedinpractice,particularlyforthesinglelevel,becauseofhighwaterusage.

8.Batterycharging

Cell Singlelevel(V/cell) Twolevel(V/cell) type

min max min max floating

L 1.43 1.50 1.47 1.70 1.42±0.01

M 1.43 1.50 1.45 1.70 1.40±0.01

H 1.43 1.50 1.45 1.70 1.40±0.01

Table4-Chargeandfloatvoltagesfortheblockbatteryranges

19

8.3 Charge acceptanceAdischargedcellwilltakeacertaintimetoachieveafullstateofcharge.Figures6(a),(b)and(c)givethecapacityavailablefortypicalchargingvoltagesrecommendedfortheblockbatteryrangeduringthefirst30hoursofchargefromafullydischargedstate.

Figure6(b)-TypicalrechargetimesfromafullydischargedstatefortheMblock

20

Figure6(a)-TypicalrechargetimesfromafullydischargedstatefortheLblock

Thesegraphsgivetherechargetimeforacurrentlimitof0.2C5A.Clearly,ifalowervalueforthecurrentisused,e.g.0.1C5A,thenthebatterywilltakelongertocharge.Ifahighercurrentisusedthenitwillchargemorerapidly.Thisisnotingeneralaproratarelationshipduetothelimitedchargingvoltage.

ThechargetimeforanMtypeplateatdifferentchargeregimesforafixedvoltageisgiveninFigure6(d).

Iftheapplicationhasaparticularrechargetimerequirementthenthismustbetakenintoaccountwhencalculatingthebattery.

Figure6(d)-TypicalrechargetimesfordifferentchargeratesfortheMblock

21

Figure6(c)-TypicalrechargetimesfromafullydischargedstatefortheHblock

8.4 Charge efficiencyThechargeefficiencyofthebatteryisdependentonthestateofchargeofthebatteryandthetemperature.Formuchofitschargeprofile,itisrechargedatahighlevelofefficiency.

Ingeneral,atstatesofchargelessthan80%thechargeefficiencyremainshigh,butasthebatteryapproachesafullychargedcondition,thechargingefficiencyfallsoff.

8.5 Temperature effectsAsthetemperatureincreases,theelectrochemicalbehaviorbecomesmoreactive,andso,forthesamefloatingvoltage,thecurrentincreases.Asthetemperatureisreducedthenthereverseoccurs.Increasingthecurrentincreasesthewaterloss,andreducingthecurrentcreatestheriskthatthecellwillnotbesufficientlycharged.

Forstandbyapplication,itisnormallynotrequiredtocompensatethechargingvoltagewiththetemperature.Howeverifwaterconsumptionisofmainconcern,temperaturecompensationshouldbeusedifthebatteryisoperatingathightemperaturesuchas+35°C(+95°F).Atlowtemperature(<0°C/+32°F),thereisariskofpoorcharginganditisrecommendedeithertoadjustthechargingvoltageortocompensatethechargingvoltagewiththetemperature.

Valueofthetemperaturecompensation:–3mV/°C(–1.7mV/°F),startingfromanambienttemperatureof+20°Cto+25°C(+68°Fto+77°F).

8.6 Commissioning*Itisrecommendedthatagoodfirstchargeshouldbegiventothebattery.Thisisaonceonlyoperation,andisessentialtopreparethebatteryforitslongservicelife.Itisalsoimportantfordischargedandemptycellswhichhavebeenfilled,astheywillbeinatotallydischargedstate.

Aconstantcurrentfirstchargeispreferableandthisshouldbesuchastosupply200%oftheratedcapacityofthecell.Thus,a250Ahcellwillrequire500ampere-hours’input,e.g.50Afor10hours.

* Please refer to the installation and operating instructions (see section 10).

22

9.1 Electrical abuseRippleeffectsThenickel-cadmiumbatteryistoleranttohighrippleandwillacceptripplecurrentsofupto0.2C5AI eff.Infact,theonlyeffectofahighripplecurrentisthatofincreasedwaterusage.Thus,ingeneral,anycommerciallyavailablechargerorgeneratorcanbeusedforcommissioningormaintenancechargingoftheblockbattery.Thiscontrastswiththevalve-regulatedleadacidbattery(VRLA)whererelativelysmallripplecurrentscancausebatteryoverheating,andwillreducelifeandperformance.

Over-dischargeIfmorethanthedesignedcapacityistakenoutofabatterythenitbecomesdeep-dischargedandreversed.Thisisconsideredtobeanabusesituationforabatteryandshouldbeavoided.

Inthecaseofleadacidbatteriesthiswillleadtofailureofthebatteryandisunacceptable.

Theblockbatterywillnotbedamagedbyover-dischargebutmustberechargedtocompensatefortheover-discharge.

OverchargeInthecaseoftheblockbattery,withitsgenerouselectrolytereserve,asmalldegreeofoverchargeoverashortperiodwillnotsignificantlyalterthemaintenanceperiod.Inthecaseofexcessiveovercharge,waterreplenishmentisrequired,buttherewillbenosignificanteffectonthelifeofthebattery.

9.2 Mechanical abuseShockloadsTheblockbatteryconcepthasbeentestedtoIEC68-2-29(bumptestsat5g,10gand25g)andIEC77(shocktest3g),whereg=acceleration.

VibrationresistanceTheblockbatteryconcepthasbeentestedtoIEC77for2hoursat1g,whereg=acceleration.

ExternalcorrosionTheblockbatteryismanufacturedindurablepolypropylene.Allexternalmetalcomponentsarenickel-platedorstainlesssteel,protectedbyananti-corrosionoil,andthenprotectedbyarigidplasticcover.

9.Specialoperatingfactors23

Important recommendationsn Never allow an exposed flame

or spark near the batteries, particularly while charging.

n Never smoke while performing any operation on the battery.

n For protection, wear rubber gloves, long sleeves, and appropriate splash goggles or face shield.

n The electrolyte is harmful to skin and eyes. In the event of contact with skin or eyes, wash immediately with plenty of water. If eyes are affected, flush with water, and obtain immediate medical attention.

n Remove all rings, watches and other items with metal parts before working on the battery.

n Use insulated tools.n Avoid static electricity and

take measures for protection against electric shocks.

n Discharge any possible static electricity from clothing and/or tools by touching an earth-connected part “ground” before working on the battery.

10.1 Receiving the shipmentUnpackthecellsimmediatelyuponarrival.Donotoverturnthepackage.Transportsealsarelocatedunderthecoveroftheventplug.

nIf the cells are shipped filled and charged,thecellsarereadyforassembly.Removetheplastictransportsealsonlybeforeuse.

nIf the cells are shipped empty and discharged,donotremovetheplastictransportsealsuntilreadytofillthecells.

The cells must never be charged with the transport seals in place as this can cause permanent damage.

10.2 StorageStorethebatteryindoorsinadry,clean,coollocation(0°Cto+30°C/+32°Fto+86°F)andwellventilatedspaceonopenshelves.

Donotstoreindirectsunlightorexposetoexcessiveheat.

n Cells filled and charged

•Ifcellsarestoredfilled,theymustbefullychargedpriortostorage.•Cellsmaybestoredfilledandchargedforaperiodnotexceeding12monthsfromdateofdispatchfromfactory.

Storageofafilledbatteryattemperaturesabove+30°C(+86°F)canresultinlossofcapacity.Thiscanbeasmuch

as5%per10°C(18°F)above+30°C(+86°F)peryear.

n Cells empty and discharged

•Saftrecommendstostorecellsemptyanddischarged.ThisensurescompliancewithIEC60623section4.9(storage).•Cellscanbestoredlikethisformanyyears.

n Whendeliveriesaremadeincardboardboxes,storewithoutopeningtheboxes.

n When deliveries are made in plywood boxes, open the boxes before the storage. The lid and the packing material on top of the cells must be removed.

10.Installationand operatinginstructions

24

10.3 Electrolyte / cell oiln Cells delivered filled and

charged:Checkthelevelofelectrolyte.Itshouldnotbemorethan20mmbelowthemaximumlevelmark(upper).Ifthisisnotthecase,adjustthelevelwithdistilledordeionizedwater.Cellsdeliveredfilledhavealreadycelloilinplace.

Incaseofspillageofelectrolyteduringthetransport,thecellshavetobetopped-upwithE22electrolyte.Fillthecellsabout20mmabovetheminimumlevelmark(lower)withelectrolyte.Wait4hoursandadjustifnecessarybeforecommissioning.

n Cells delivered empty and discharged:

Iftheelectrolyteissupplieddry,prepareitaccordingtoitsseparateinstructionssheet.TheelectrolytetobeusedisE22.Removethetransportsealsjustbeforefilling.

Fillthecellsabout20mmabovetheminimumlevelmark(lower)withelectrolyte.

Wait4to24hoursandadjustifnecessarybeforecommissioning.

Itisrecommendedtoaddthecelloilafterthecommissioningcharge,withthesyringe,

accordingtothequantityindicatedintheInstallationandOperatingInstructionssheet.

10.4 Installation10.4.1 LocationInstallthebatteryinadryandcleanroom.Avoiddirectsunlightandheat.Thebatterywillgivethebestperformanceandmaximumservicelifewhentheambienttemperatureisbetween+10°Cto+30°C(+50°Fto+86°F).

10.4.2 VentilationDuringthelastpartofcharging,thebatteryisemittinggases(oxygenandhydrogenmixture).Atnormalfloat-chargethegasevolutionisverysmallbutsomeventilationisnecessary.

Note that special regulations for ventilation may be valid in your area depending on the application.

10.4.3 MountingVerifythatcellsarecorrectlyinterconnectedwiththeappropriatepolarity.Thebatteryconnectiontoloadshouldbewithnickelplatedcablelugs.Recommendedtorquesforterminalboltsare:•M6=11±1.1N.m(97.4±9.8lbf.in)•M8=20±2N.m(177.0±17.7lbf.in)•M10=30±3N.m(265.0±26.6lbf.in)

Theconnectorsandterminalsshouldbecorrosion-protectedbycoatingwithathinlayerofanti-corrosionoil.

Remove the transport seals and close the vent plugs.

10.5 CommissioningVerify that the transport seals are removed, the vents are closed and the ventilation is adequate during this operation.

Agoodcommissioningisimportant.Chargeatconstantcurrentispreferable.

IfthecurrentlimitislowerthanindicatedintheInstallationandOperatingInstructionssheet,chargeforaproportionallylongertime.

n For cells filled and charged by the factory and stored less than 6 months:

• Constant current charge:Chargefor10hat0.2C5Arecommended(seetheInstallationandOperatingInstructionssheet).

Note:Attheendofthecharge,thecellvoltagemayreachthelevelof1.85Vpercell,thusthechargershallbeabletosupplysuchvoltage.Whenthechargermaximumvoltagesettingistoolowtosupplyconstantcurrentcharging,dividethebattery

25

intotwopartstobechargedindividually.• Constant voltage charge:Chargefor24hat1.65V/cell,currentlimitedto0.2C5Aorchargefor48hat1.55V/cell,currentlimitedto0.2C5A(seetheInstallationandOperatingInstructionssheet).

n For cells filled on location or for filled cells which have been stored more than 6 months:

• Constant current charge:a) Chargefor10hat0.2C5Arecommended(seetheInstallationandOperatingInstructionssheet).

b) Dischargeat0.2C5Ato1.0V/cell

c)Chargefor10hat0.2C5Arecommended(seetheInstallationandOperatingInstructionssheet).

Note: Attheendofthecharge,thecellvoltagemayreachthelevelof1.85Vpercell,thusthechargershallbeabletosupplysuchvoltage.

Whenthechargermaximumvoltagesettingistoolowtosupplyconstantcurrentcharging,dividethebatteryintotwopartstobechargedindividually.

• Constant voltage charge:a) Chargefor30hat1.65V/cellwithcurrentlimitedto0.2C5A(seetheInstallationandOperatingInstructionssheet).

b) Dischargeat0.2C5Ato1.0V/cell

c)Chargefor30 hat1.65V/cellwithcurrentlimitedto0.2C5Aorchargefor48hat1.55V/cellcurrentlimitedto0.2C5A(seetheInstallationandOperatingInstructionssheet).

nCell oil & electrolyte after commissioning:waitfor4hoursaftercommissioning.

• For cells delivered filled by the factory:- Celloilisalreadyinplace.- Checktheelectrolytelevelandadjustittothemaximumlevelmark(upper)byaddingdistilledordeionizedwater.

• For cells filled on location:- Addthecelloilwiththesyringe,accordingtothequantityindicatedintheInstallationandOperatingInstructionssheet.- Checktheelectrolytelevelandadjustittothemaximumlevelmark(upper)byadding:electrolyte.

Thebatteryisreadyforuse.

For capacity test purposes, the battery has to be charged in accordance with IEC 60623 section 4.

10.6 Charging in servicen Continuous parallel

operation,withoccasionalbatterydischarge.Recommendedchargingvoltage(+20°Cto+25°C/+68°Fto+77°F):

For two level charge:•floatlevel=1.42±0.01V/cellforLcells=1.40±0.01V/cellforMandHcells

•highlevel=1.47-1.70V/cellforLcells=1.45-1.70V/cellforMandHcells.

Ahighvoltagewillincreasethespeedandefficiencyoftherecharging.

For single level charge:•floatlevel:1.43-1.50V/cell.

nBuffer operation,wheretheloadexceedsthechargerrating.

Recommendedchargingvoltage(+20°Cto+25°C/+68°Fto+77°F):1.50-1.60V/cell.

26

27

10.7 Periodic maintenancen Keepthebatterycleanusingonlywater.Donotuseawirebrushorsolventsofanykind.Ventplugscanberinsedincleanwaterifnecessary.

n Checktheelectrolytelevel.Neverletthelevelfallbelowtheminimumlevelmark(lower).Useonlydistilledordeionizedwatertotop-up.Experiencewilltellthetimeintervalbetweentopping-up.

Note: Oncethebatteryhasbeenfilledwiththecorrectelectrolyteeitheratthebatteryfactoryorduringthebatterycommissioning,thereisnoneedtochecktheelectrolytedensityperiodically.Interpretationofdensitymeasurementsisdifficultandcouldbemisleading.

n Checkthechargingvoltage.Ifabatteryisparallelconnected,itisimportantthattherecommendedchargingvoltageremainsunchanged.Thechargingvoltageshouldbecheckedandrecordedatleastonceyearly.Ifacellfloatvoltageisfoundbelow1.35V,high-ratechargeisrecommendedtoapplytothecellconcerned.

n Checkeverytwoyearsthatallconnectorsaretight.Theconnectorsandterminalboltsshouldbecorrosion-protectedbycoatingwithathinlayerofanti-corrosionoil.

n Highwaterconsumptionisusuallycausedbyhighimpropervoltagesettingofthecharger.

10.8 Changing electrolyteInmoststationarybatteryapplications,theelectrolytewillretainitseffectivenessforthelifeofthebattery.However,underspecialbatteryoperatingconditions,iftheelectrolyteisfoundtobecarbonated,thebatteryperformancecanberestoredbyreplacingtheelectrolyte.

Theelectrolytetypetobeusedforreplacementinthesecellsis:E13.

Referto“ElectrolyteInstructions”.

28

Inacorrectlydesignedstandbyapplication,theblockbatteryrequirestheminimumofattention.However,itisgoodpracticewithanysystemtocarryoutaninspectionofthesystematleastonceperyear,orattherecommendedtopping-upintervalperiodtoensurethatthecharger,thebatteryandtheauxiliaryelectronicsareallfunctioningcorrectly.

Whenthisinspectioniscarriedout,itisrecommendedthatcertainproceduresshouldbecarriedouttoensurethatthebatteryismaintainedinagoodstate.

11.1 Cleanliness/mechanicalCellsmustbekeptcleananddryatalltimes,asdustanddampcausecurrentleakage.Terminalsandconnectorsshouldbekeptclean,andanyspillageduringmaintenanceshouldbewipedoffwithacleancloth.Thebatterycanbecleaned,usingwater.Donotuseawirebrushorasolventofanykind.Ventcapscanberinsedincleanwater,ifnecessary.

Checkthattheflame-arrestingventsaretightlyfittedandthattherearenodepositsontheventcaps.

Terminalsshouldbecheckedfortightness,andtheterminalsandconnectorsshouldbecorrosion-protectedbycoatingwithathinlayerofneutralgreaseoranti-corrosionoil.

11.2 Topping-upChecktheelectrolytelevel.NeverletthelevelfallbelowthelowerMINmark.Useonlyapproveddistilledordeionizedwatertotop-up.Donotoverfillthecells.

Excessiveconsumptionofwaterindicatesoperationattoohighavoltageortoohighatemperature.Negligibleconsumptionofwater,withbatteriesoncontinuouslowcurrentorfloatcharge,couldindicateunder-charging.Areasonableconsumptionofwateristhebestindicationthatabatteryisbeingoperatedunderthecorrectconditions.Anymarkedchangeintherateofwaterconsumptionshouldbeinvestigatedimmediately.

Thetopping-upintervalcanbecalculatedasdescribedinsection6.9.However,itisrecommendedthat,initially,electrolytelevelsshouldbemonitoredmonthlytodeterminethefrequencyoftopping-uprequiredforaparticularinstallation.

Safthasafullrangeoftopping-upequipmentavailabletoaidthisoperation.

11.Maintenanceofblockbatteriesinservice

11.3 Capacity checkElectricalbatterytestingisnotpartofnormalroutinemaintenance,asthebatteryisrequiredtogivethebackupfunctionandcannotbeeasilytakenoutofservice.

However,ifacapacitytestofthebatteryisneeded,thefollowingprocedureshouldbefollowed:

a)Dischargethebatteryattherateof0.1C5to0.2C5A(10to20Afora100Ahbattery)toafinalaveragevoltageof1.0V/cell(i.e.92voltsfora92cellbattery)

b)Charge200%(i.e.200Ahfora100Ahbatteryatthesamerateusedina)

c)Dischargeatthesamerateusedina),measuringandrecordingcurrent,voltageandtimeeveryhour,andmorefrequentlytowardstheendofthedischarge.Thisshouldbecontinueduntilafinalaveragevoltageof1.0V/cellisreached.Theoverallstateofthebatterycanthenbeseen,andifindividualcellmeasurementsaretaken,thestateofeachcellcanbeobserved.

11.4 Recommended maintenance procedureInordertoobtainthebestfromyourbattery,thefollowingmaintenanceprocedureisrecommended.

Itisalsorecommendedthatamaintenancerecordbekeptwhichshouldincludearecordofthetemperatureofthebatteryroom.

Yearly

checkchargevoltagesettings

checkcellvoltages

(50mVdeviationfromaverage

isacceptable)

checkfloatcurrentofthebattery

checkelectrolytelevel

highvoltagechargeifagreed

forapplication

Every2years

cleancelllidsandbatteryarea

checktorquevalues,grease

terminalsandconnectors

Every5yearsorasrequired

capacitycheck

Asrequired

top-upwithwateraccordingto

definedperiod(dependonfloat

voltage,cyclesandtemperature)

29

30

Inaworldwhereautonomoussourcesofelectricpowerareevermoreindemand,Saftbatteriesprovideanenvironmentallyresponsibleanswertotheseneeds.EnvironmentalmanagementliesatthecoreofSaft’sbusinessandwetakecaretocontroleverystageofabattery’slife-cycleintermsofpotentialimpact.Environmentalprotectionisourtoppriority,fromdesignandproductionthroughend-of-lifecollection,disposalandrecycling.

Ourrespectfortheenvironmentiscomplementedbyanequalrespectforourcustomers.Weaimtogenerateconfidenceinourproducts,notonlyfromafunctionalstandpoint,butalsointermsoftheenvironmentalsafeguardsthatarebuiltintotheirlife-cycle.Thesimpleanduniquenatureofthebatterycomponentsmakethemreadilyrecyclableandthisprocesssafeguardsvaluablenaturalresourcesforfuturegenerations.

Inpartnershipwithcollectionagenciesworldwide,Saftorganizesretrievalfrompre-collectionpointsandtherecyclingofspentSaftbatteries.InformationaboutSaft’scollectionnetworkcanbefoundonourwebsite:

Ni-Cdbatteriesmustnotbediscardedasharmlesswasteandshouldbetreatedcarefullyinaccordancewithlocalandnationalregulations.YourSaftrepresentativecanassistwithfurtherinformationontheseregulationsandwiththeoverallrecyclingprocedure.

12.Disposalandrecycling

www.saftbatteries.com

Saftiscommittedtothehigheststandardsofenvironmentalstewardship.Aspartofitsenvironmentalcommitment,Saftgivesprioritytorecycledrawmaterialsovervirginrawmaterials,reducesitsplants’ releases toairandwater yearafter year,minimizeswaterusage, reduces fossil energyconsumptionandassociatedCO2emissions,andensuresthatitscustomershaverecyclingsolutionsavailablefortheirspentbatteries.

RegardingindustrialNi-Cdbatteries,SafthashadpartnershipsformanyyearswithcollectioncompaniesinmostEUcountries,inNorthAmericaandinothercountries.Thiscollectionnetworkreceivesanddispatchesourcustomers’batteriesattheendoftheirlivestofullyapprovedrecyclingfacilities,incompliancewiththelawsgoverningtrans-boundarywasteshipments.ThiscollectionnetworkisundergoingminoradaptationstomeettherequirementsoftheEUbatteriesdirective.Alistofourcollectionpointsisavailableonourwebsite.Inothercountries,Saftassistsusersofitsbatteriesinfindingenvironmentallysoundrecyclingsolutions.Pleasecontactyoursalesrepresentativeforfurtherinformation.

SaftIndustrialBatteryGroup12,rueSadiCarnot93170Bagnolet–FranceTel:+33(0)149931918Fax:+33(0)149931964

www.saftbatteries.com

DocN˚21081-2-0511Edition:May2011Datainthisdocumentissubjecttochangewithoutnoticeandbecomescontractualonlyafterwrittenconfirmation.

Photocredit:©Royalty-Free/Corbis,PhotoDisc,Saft.

SociétéparActionsSimplifiéeaucapitalde31944000€RCSBobignyB383703873

ProducedintheUKbyArthurAssociatesLimited.

AfricaSaftexportsalesdpt,FranceTel.:+33149931918Fax:+33149931956

ArgentinaEnergiaAlcalina,BuenosAiresTel.:+541143349034/35Fax:+541143425024

AustraliaSaftAustraliaPtyLtd,SevenHillsTel.:+61296740700Fax:+61296209990

AustriaStatronGmbH,WienTel.:+4316174060Fax:+4316174060/40

BelgiumAEGBelgiumSA,BrusselsTel.:+3225296543Fax:+3225296449

BrazilAdelcoSistemasdeEnergiaLtda.,SãoPauloTel.:+551141997500Fax:+551141615307

CanadaPleasecontactUSAoffice

ChinaSaft(ZhuhaiFreeTradeZone)BatteriesCoLtd,ShanghaiTel.:+862158666405Fax:+862158666403

CzechRepublicSaftFeraka.s.,PragueTel.:+420257013260Fax:+420257013261

DenmarkScansupplyA/S,BirkeroedTel.:+4545825090Fax:+4545825440

FinlandHansaBatteryOy,EspooTel.:+358207631883Fax:+358207631889

FranceSaftFrance,BagnoletTel.:+33149931918Fax:+33149931964

GermanySaftBatterienGmbH,NürnbergTel.:+4991194174-0Fax:+49911426144

HongKong(Stationary,railway,telecomandrenewableapplications)SaftHongKongLtd.,KowloonTel.:+85235687066Fax:+85227980619

IndiasubcontinentAMCO-SaftIndiaLtd,Bangalore,IndiaTel.:+918023637790Fax:+918023637716

ItalySaftBatterieItaliaS.r.l.,Segrate(Milano)Tel.:+390289280747Fax:+390289280762

JapanSumitomoCorp.,TokyoTel.:+81351449082Fax:+81351449267

KoreaEnersysKoreaCo.Ltd,SeoulTel.:+8225010033Fax:+8225010034

MexicoTroopyCompania,SAdeCV,MexicoTel.:+525550821030Fax:+525550821039

MiddleEastSaftNifeMELtd,Limassol,CyprusTel.:+35725820040Fax:+35725748492

NetherlandsSaftBatterijenB.V.,EindhovenTel.:+31402721900Fax:+31402721904

NorwaySaftAS,OsteraasTel.:+4767164160Fax:+4767164170

RussiaZAOAncor,MoscowTel.:+74957885204Fax:+78989581323

SingaporeSaftBatteriesPteLtd,SingaporeTel.:+6565121500Fax:+6567497282

SpainSaftBateriasS.L.SanSebastiandelosReyesTel.:+34916593480Fax:+34916593490

SwedenSaftAB,OskarshamnTel.:+4649168000Fax:+4649168180

SwitzerlandStatronAG,MägenwilTel.:+41628874887Fax:+41628874888

UnitedKingdomSaftLtd,HarlowTel.:+441279772550Fax:+441279420909

USASaftAmericaInc.,(Stationaryandrenewableapplications)NorthHaven(CT)Tel.:+12032394718Fax:+12032347598(Telecomapplications)Valdosta(GA)Tel.:+12292452854Fax:+12292478486(Rail/TransitSales)Cockeysville(MD)Tel.:+14107713200Fax:+14107711144

VenezuelaCorporaciónINTELECC.A.,CaracasTel.:+582129631122Fax:+582129614908

WesternAsiaExportsalesdpt,SwedenTel.:+4649168000Fax:+4649168180