ASTM D7148-19a

Standard Test Method for Determining the Ionic Resistivity (ER) of Alkaline Battery Separator Using a Carbon Electrode in an Electrolyte Bath Measuring System

SIGNIFICANCE AND USE
5.1 The ER of a battery separator is a standard measurement used by separator and battery manufacturers for quality control purposes and separator selection.  
5.2 Separator ER and the separator's interaction with the electrolyte, that is resistance to wetting or flow, will contribute to the internal resistance of the battery and this has the potential to limit the electrical output of a battery. The ER determination is a tool for battery manufacturers to use in design, material selection, and performance specifications.  
5.3 The change in the bath electrical resistance imparted by a separator is affected by the porosity, thickness, and tortuousity of the pore structure of the separator, the wettability of the separator to the electrolyte, and the temperature and concentration of the electrolyte.  
5.4 Incomplete wetting or saturation of the pore structure limits the lowest ER value obtainable from a separator structure. Separators are pretreated to assure that the specimen being tested has been adequately wetted out. A separator that is not fully wetted out (saturated) will give a higher ER.  
5.5 This test method is intended to give a rapid and repeatable measurement that approximates the change in ER that could happen when the separator is used in a battery.
SCOPE
1.1 This test method covers the pretreatment, test conditions, apparatus, and procedure to determine the ionic resistivity, commonly referred to in the battery industry as electrical resistance (ER) of an alkaline battery separator immersed in an electrolyte of 40 % potassium hydroxide (KOH).  
1.2 The values stated in SI units are to be regarded as the standard.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.  
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 31-Oct-2019
• ICS: 29.220.30 - Alkaline secondary cells and batteries
• Technical Committee: D09 - Electrical and Electronic Insulating Materials
• Drafting Committee: D09.01 - Electrical Insulating Products

Relations

• Refers: ASTM E2935-14 - Standard Practice for Conducting Equivalence Testing in Laboratory Applications
• Effective Date: 01-Oct-2014
• Refers: ASTM D1711-14a - Standard Terminology Relating to Electrical Insulation
• Effective Date: 01-Nov-2014
• Refers: ASTM E2935-15 - Standard Practice for Conducting Equivalence Testing in Laboratory Applications
• Effective Date: 01-Oct-2015
• Refers: ASTM E2935-16 - Standard Practice for Conducting Equivalence Testing in Laboratory Applications
• Effective Date: 15-Nov-2016
• Refers: ASTM D1711-15 - Standard Terminology Relating to Electrical Insulation
• Effective Date: 01-Nov-2015
• Refers: ASTM E2935-17 - Standard Practice for Conducting Equivalence Testing in Laboratory Applications
• Effective Date: 01-Oct-2017

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D7148 − 19a
Standard Test Method for
Determining the Ionic Resistivity (ER) of Alkaline Battery
Separator Using a Carbon Electrode in an Electrolyte Bath
1
Measuring System
This standard is issued under the fixed designation D7148; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
3
1. Scope* System, Section 3.3b
1.1 This test method covers the pretreatment, test
3. Terminology
conditions, apparatus, and procedure to determine the ionic
3.1 Definitions of Terms Specific to This Standard:
resistivity, commonly referred to in the battery industry as
3.1.1 barrier resistance (RB), n—the resistance of the bath
electrical resistance (ER) of an alkaline battery separator
with a solid, nonporous sheet of alkaline resistant, electrical
immersed in an electrolyte of 40 % potassium hydroxide
insulation that separates the electrodes.
(KOH).
3.1.2 bath resistance (RC), n—the resistance of the bath
1.2 The values stated in SI units are to be regarded as the
without the specimen (separator).
standard.
3.1.3 bath resistance (RT), n—the total electrical resistance
1.3 This standard does not purport to address all of the
of the bath and a separator specimen.
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro- 3.1.4 battery separator, n—an ion-permeable, nonconduc-
priate safety, health, and environmental practices and deter- tive material that prevents electrical contact between electrodes
mine the applicability of regulatory limitations prior to use. of opposite polarity.
1.4 This international standard was developed in accor-
3.1.5 electrolyte, n—a 40 % potassium hydroxide solution.
dance with internationally recognized principles on standard-
3.1.6 ionic resisitivity (ER), n—the product of a change in
ization established in the Decision on Principles for the
electrical resistance times an area.
Development of International Standards, Guides and Recom-
3.1.6.1 Discussion—The area is the aperture area divided by
mendations issued by the World Trade Organization Technical
the number of separators between the electrodes. The change in
Barriers to Trade (TBT) Committee.
resistance is the difference, in ohms, of the electrical resistance
with and without the seperator(s). The SI units for ER are
2. Referenced Documents
2
ohms-metre but the customary practice in the battery industry
2
2
2.1 ASTM Standards:
is to report the ER in units of ohms-cm . This terminology is
D1711 Terminology Relating to Electrical Insulation
not in conflict with Terminology D1711.
E691 Practice for Conducting an Interlaboratory Study to
3.2 Symbols:
Determine the Precision of a Test Method
3.2.1 ER—a symbol, peculiar to the battery industry, denot-
E2935 Practice for Evaluating Equivalence of Two Testing
ing that characteristic of a sheet material that is related to the
Processes
rate of transfer of ions through the interstices of a porous sheet
2.2 Battery Council International:
immersed between two carbon electrodes in an aqueous
Standard Test Method for Determining the Electrical Resis-
electroyte.
tance of a Battery Separator Using a Palico Measuring
4. Summary of Test Method
4.1 This test method detects small changes in ohmic resis-
1
This test method is under the jurisdiction of ASTM Committee D09 on
Electrical and Electronic Insulating Materials and is the direct responsibility of tance between carbon electrodes immersed in an alkaline
Subcommittee D09.01 on Electrical Insulating Products.
electrolyte with and without separator material between the
Current edition approved Nov. 1, 2019. Published November 2019. Last previous
carbon electrodes. This change is related to the rate of transfer
edition approved in 2019 as D7148 – 19. DOI: 10.1520/D7148-19A.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
3
Standards volume information, refer to the standard’s Document Summary page on Available from Battery Council International, 330 N. Wabash Ave., Ste. 2000,
the ASTM website. Chicago, IL 60611.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D7148 − 19a
of ions through a separator material. The ER is calculated from 8
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D7148 − 19 D7148 − 19a An American National Standard
Standard Test Method for
Determining the Ionic Resistivity (ER) of Alkaline Battery
Separator Using a Carbon Electrode in an Electrolyte Bath
1
Measuring System
This standard is issued under the fixed designation D7148; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope*
1.1 This test method covers the pretreatment, test conditions, apparatus, and procedure to determine the ionic resistivity,
commonly referred to in the battery industry as electrical resistance (ER) of an alkaline battery separator immersed in an electrolyte
of 40 % potassium hydroxide (KOH).
1.2 The values stated in SI units are to be regarded as the standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory
limitations prior to use.
1.4 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2
2.1 ASTM Standards:
D1711 Terminology Relating to Electrical Insulation
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
E2935 Practice for Conducting Equivalence Testing in Laboratory Applications
2.2 Battery Council International:
Standard Test Method for Determining the Electrical Resistance of a Battery Separator Using a Palico Measuring
3
System, Section 3.3b
3. Terminology
3.1 Definitions of Terms Specific to This Standard:
3.1.1 barrier resistance (RB), n—the resistance of the bath with a solid, nonporous sheet of alkaline resistant, electrical
insulation that separates the electrodes.
3.1.2 bath resistance (RC), n—the resistance of the bath without the specimen (separator).
3.1.3 bath resistance (RT), n—the total electrical resistance of the bath and a separator specimen.
3.1.4 battery separator, n—an ion-permeable, nonconductive material that prevents electrical contact between electrodes of
opposite polarity.
3.1.5 electrolyte, n—a 40 % potassium hydroxide solution.
3.1.6 ionic resisitivity (ER), n—the product of a change in electrical resistance times an area.
1
This test method is under the jurisdiction of ASTM Committee D09 on Electrical and Electronic Insulating Materials and is the direct responsibility of Subcommittee
D09.01 on Electrical Insulating Products.
Current edition approved March 1, 2019Nov. 1, 2019. Published March 2019Nvember 2019. Last previous edition approved in 20132019 as D7148 – 13.D7148 – 19. DOI:
10.1520/D7148-19.10.1520/D7148-19A.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
3
Available from Battery Council International, 330 N. Wabash Ave., Ste. 2000, Chicago, IL 60611.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D7148 − 19a
3.1.6.1 Discussion—
The area is the aperture area divided by the number of separators between the electrodes. The change in resistance is the difference,
2
in ohms, of the electrical resistance with and without the seperator(s). The SI units for ER are ohms-metre but the customary
2
practice in the battery industry is to report the ER in units of ohms-cm . This terminology is not in conflict with Terminology
D1711.
3.2 Symbols:
3.2.1 ER—a symbol, peculiar to the battery industry, denoting that characteristic of a sheet material that is related to the rate
of transfer of ions through the interstices of a porous sheet immersed between two carbon electrodes in an aqueous electroyte.
4. Summary of Test Method
4.1 This test method detects small changes in ohmic resistance between carbon electrodes immersed in an alkali
...