ASTM_D_7129_-_09.pdf

Designation:D712909StandardTest Method forDetermination of Ammonia Trapping in a Grafted BatterySeparator1This standard is issued under the fixed designation D7129;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This test method covers the measurement of the abilityof a material to capture ammonia.1.2 This test method is intended primarily for testing graftedpolyolefin materials used as a battery separator,although othermaterials could be tested.1.3 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.4 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D123 Terminology Relating to TextilesE438 Specification for Glasses in Laboratory ApparatusE1272 Specification for Laboratory Glass Graduated Cylin-ders3.Terminology3.1 Definitions:3.1.1 For definitions on other textile terms in this testmethod,refer to Terminology D1234.Summary of Test Method4.1 A predetermined amount of separator and ammoniumhydroxide is added together in a KOH solution.The specimensare conditioned under a controlled temperature for 24 h.Afterthe solution is cooled,the solutions are distilled to determinethe amount of ammonia the separator retained.4.2 Results are calculated as mol/g using the appropriateequations.5.Significance and Use5.1 Nickel metal hydride(Ni-MH)cells/batteries can ex-hibit high self-discharge rates.Nitrate impurities in the positiveelectrode can be reduced to ammonia on the negative electrode.This causes rapid self-discharge.Technical publications havereported a link between the separator ammonia trappingcapabilities and the cells charge retention.Grafted polyolefinseparators can absorb or trap these impuritieshence,reduc-ing self-discharge rates.The level of ammonia trapping fromthis method gives an indication of the efficiency of a separatorto trap these contaminates,thus helping a battery self discharge(charge retention).A higher value should allow a cell to havegreater charge retention.6.Apparatus6.1 Flask,Erlenmeyer,wide mouth,250 mL capacity with ascrew cap.6.2 Flask,Erlenmeyer,wide mouth,500 mL capacity.6.3 Cylinder,Graduated,Class A,250 mL capacity.NOTE1The tolerance on the accuracy of the graduations in Specifi-cation E1272 for this apparatus is 61.4 mL.If greater accuracy is requiredfor a test result,the graduated trap(s)should be calibrated.6.4 Pipette,Volumetric,Class A,10 mL capacity.NOTE2The tolerance on the accuracy of the graduations in Specifi-cation E438 for this apparatus is 60.02 mL3.If greater accuracy isrequired for a test result,the graduated trap(s)should be calibrated6.5 Pipette,Volumetric,Class A,3-mL capacity.NOTE3The tolerance on the accuracy of the graduations in Specifi-cation E438 for this apparatus is 60.01 mL.If greater accuracy is requiredfor a test result,the graduated trap(s)should be calibrated.6.6 Distillation Unit,Micro or macro Kjeldhal apparatus.6.7 Oven.7.Reagents7.1 Ammonium Hydroxide,0.3M(NH4OH),ACS grade.7.2 Hydrochloric Acid,0.1M(HCL),ACS grade.1This test method is under the jurisdiction of ASTM Committee D09 onElectrical and Electronic Insulating Materials and is the direct responsibility ofSubcommittee D09.19 on Dielectric Sheet and Roll Products.Current edition approved Oct.1,2009.Published November 2009.Originallyapproved in 2005.Last previous edition approved in 2005 as D7129 05.DOI:10.1520/D7129-09.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesNOTICE:This standard has either been superseded and replaced by a new version or withdrawn.Contact ASTM International(www.astm.org)for the latest information17.3 Methyl Red,ACS grade.7.4 Potassium Hydroxide Solution,8MPrepare a sufficientquantity of KOH solution for the testing program immediatelyat hand as follows.7.4.1 To a 1500-cm3(mL)beaker add 800 to 850 cm3(mL)of distilled water.Slowly add 448 g of potassium hydroxidepellets,certified ACS grade,to the beaker.Allow cooling toroom temperature.7.5 Potassium Hydroxide,0.1M(KOH),ACS grade.(WarningFollow appropriate safe handling procedureswhen using acids or bases.)8.Conditioning8.1 Determine sampling based on grafting process.Then cuttest