IEC TS 62282-1:2010

IEC/TS 62282-1 ®
Edition 2.0 2010-04
TECHNICAL
SPECIFICATION
SPÉCIFICATION
TECHNIQUE
Fuel cell technologies –
Part 1: Terminology
Technologies des piles à combustible –
Partie 1: Terminologie
IEC/TS 62282-1:2010
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IEC/TS 62282-1 ®
Edition 2.0 2010-04
TECHNICAL
SPECIFICATION
SPÉCIFICATION
TECHNIQUE
Fuel cell technologies –
Part 1: Terminology
Technologies des piles à combustible –
Partie 1: Terminologie
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
W
CODE PRIX
ICS 27.070 ISBN 978-2-88910-661-5
– 2 – TS 62282-1 © IEC:2010
CONTENTS
FOREWORD.3
1 Scope.5
2 Diagrams of generalized fuel cell systems .5
2.1 Diagrams.5
2.2 Definition of diagram functions .7
3 Terms and definitions .8
Bibliography.31
Index .32

Figure 1 – Stationary fuel cell power systems (3.49.3) .5
Figure 2 – Portable fuel cell power systems (3.49.2) .6
Figure 3 – Micro fuel cell power systems (3.49.1) .6
Figure 4 – Fuel cell vehicles (3.51) .7

TS 62282-1 © IEC:2010 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FUEL CELL TECHNOLOGIES –
Part 1: Terminology
FOREWORD
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The main task of IEC technical committees is to prepare International Standards. In
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• the required support cannot be obtained for the publication of an International Standard,
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• the subject is still under technical development or where, for any other reason, there is the
future but no immediate possibility of an agreement on an International Standard.
Technical specifications are subject to review within three years of publication to decide
whether they can be transformed into International Standards.
IEC 62282-1, which is a technical specification, has been prepared by IEC technical
committee 105: Fuel cell technologies.

– 4 – TS 62282-1 © IEC:2010
This second edition cancels and replaces the first edition, published in 2005. This second
edition constitutes a technical revision.
The first edition of IEC TS 62282-1 was intended as a resource for the working groups of TC
105 and users of the TC 105 standards series; therefore it only included terms and definitions
used in the other IEC 62282 standards to provide consistency among those documents. This
second edition is a general fuel cell glossary, including all terms unique to fuel cell
technologies, and it is a complete re-write of the previous edition.
The text of this technical specification is based on the following documents:
Enquiry draft Report on voting
105/200/DTS 105/250/RVC
Full information on the voting for the approval of this technical specification can be found in
the report on voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be be
• transformed into an International standard,
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
TS 62282-1 © IEC:2010 – 5 –
FUEL CELL TECHNOLOGIES –
Part 1: Terminology
1 Scope
This part of IEC 62282 provides uniform terminology in the forms of diagrams, definitions and
equations related to fuel cell technologies in all applications including but not limited to
stationary power, transportation, portable power and micro power applications.
Not found here are words and phrases, which can be found in standard dictionaries,
engineering references or the IEC 60050 series.
NOTE The first edition of IEC 62282 was intended as a resource for the working groups and users of the IEC TC
105 series of fuel cell standards. This second edition has been expanded into a general fuel cell glossary.
2 Diagrams of generalized fuel cell systems
2.1 Diagrams
Fuel cell power system
System boundary
Power inputs
Electrical
Thermal
thermal Recovered
management
heat
mechanical
system
Waste heat
Fuel
processing
Fuel
system
Power
Fuel
conditioning
cell stack
Useable power
system
or
Electrical
module
Oxidant
processing
Oxidant
system
Water
Internal power
Discharge
treatment
needs
Ventilation system water
Inert gas
Exhaust gases,
Ventilation
Onboard
ventilation
Water Automatic
system
energy
control
storage
system EMI,
noise,
EMD,
vibration, vibration
wind, rain,
temperature,
etc.
IEC  724/10
Figure 1 – Stationary fuel cell power systems (3.49.3)

– 6 – TS 62282-1 © IEC:2010
Fuel cell power system
System boundary
Power inputs
Thermal
Electrical
management
thermal
system
Waste heat
Fuel
processing
Fuel
system
Fuel
cell stack Power
conditioning
Useable power
system
Electrical
Oxidant
processing
Oxidant
system
Water
Internal power
Discharge
treatment
needs
Ventilation system water
Inert gas
Exhaust gases,
Ventilation
Onboard
ventilation
Water Automatic
system
energy
control
storage
system EMI,
noise,
EMD,
vibration
vibration,
wind, rain,
temperature,
etc.
IEC  725/10
Figure 2 – Portable fuel cell power systems (3.49.2)

Thermal
Waste
management
heat
Water
system
cartridge
Internal power needs
(optional)
(optional)
Primary battery
Mechanical interface
(optional)
signal interface
Fuel
Fuel supply
Mechanical interface
Fuel
management
interface
signal interface
cartridge Micro fuel
cell stack
or
Power
conditioning
Internal
Power interface
Useable
system
reservoir
power
(optional)
Fuel cartridge
Air
Air
Rechargeable
management
battery or
capacitor
Waste
(optional)
Water and/or cartridge
Total control
byproduct
(optional)
system
management
Micro fuel cell power unit
Micro fuel cell power system
IEC  726/10
Figure 3 – Micro fuel cell power systems (3.49.1)

TS 62282-1 © IEC:2010 – 7 –
FUEL
FUEL
EXTERNAL CONTROLLER
OnBOARD PROCESSING
CELL
FUEL FUEL AND
SYSTEM
MODULE
TRANSMISSION WHEELS
ELECTRIC
SOURCE STORAGE (INDIRECT
MOTOR
HYDROGEN
FUEL CELL)
Fuel Cell System
OnBOARD
ENERGY
STORAGE
(INTERNAL)
Propulsion system
Fuel cell vehicle
IEC  727/10
Figure 4 – Fuel cell vehicles (3.51)
2.2 Definition of diagram functions
The overall design of the power systems anticipated by this part of IEC 62282 are formed by
an assembly of integrated systems, as necessary, intended to perform designated functions,
as follows:
• Automatic control system – System that is composed of sensors, actuators, valves,
switches and logic components that maintain the fuel cell power system (3.49) parameters
within the manufacturer’s specified limits without manual intervention.
• Fuel cell module – Equipment assembly of one or more fuel cell stacks (3.50) which
electrochemically converts chemical energy to electric energy and thermal energy
intended to be integrated into a vehicle or power generation system.
• Fuel cell stack – Equipment assembly of cells, separators, cooling plates, manifolds (3.70)
and a supporting structure that electrochemically converts, typically, hydrogen rich gas
and air reactants to DC power, heat and other reaction products.
• Fuel processing system – System of chemical and/or physical processing equipment plus
associated heat exchangers and controls required to prepare, and if necessary,
pressurize, the fuel for utilization within a fuel cell power system (3.49).
• Onboard energy storage – System of internal electric energy storage devices intended to
aid or complement the fuel cell module (3.48) in providing power to internal or external
loads.
• Oxidant processing system – System that meters, conditions, processes and may
pressurize the incoming supply of oxidant for use within the fuel cell power system (3.49).
• Power conditioning system – Equipment that is used to adapt the electrical energy
produced by the fuel cell stack(s) (3.50) to application requirements as specified by the
manufacturer.
– 8 – TS 62282-1 © IEC:2010
• Thermal management system – System that provides heating or cooling and heat rejection
to maintain the fuel cell power system (3.49) in the operating temperature range, and may
provide for the recovery of excess heat and assist in heating the power train during
startup.
• Ventilation system – System that provides air through forced or natural means to the fuel
cell power system’s (3.49) enclosure.
• Water treatment system – System that provides all of the necessary treatment of the
recovered or added water for use within the fuel cell power system (3.49).
For micro fuel cell power systems
• Fuel cartridge – Removable article that contains and supplies fuel to the micro fuel cell
power unit (3.74) or internal reservoir, not to be refilled by the user. Possible variations
include:
– attached – having its own enclosure that connects to the device powered by the micro
fuel cell power system (3.49.1);
– exterior – having its own enclosure that forms a portion of the enclosure of the device
powered by the micro fuel cell power system (3.49.1);
– insert – having its own enclosure and is installed within the enclosure of the device
powered by the micro fuel cell power system (3.49.1);
– satellite – intended to be connected to and removed from the micro fuel cell power
unit (3.74) to transfer fuel to the internal reservoir inside micro fuel cell power unit.
• Micro fuel cell power unit – Micro fuel cell power system (3.49.1) excluding its fuel
cartridge
Other terms used in the diagrams, include the following.
• Discharge water – Water discharged from the fuel cell power system (3.49) including
wastewater and condensate.
• EMD (electromagnetic disturbance) – Any electromagnetic phenomenon that may degrade
the performance of a device, equipment or system, or adversely affect living or inert
matter. [IEC 60050-161:1990, 161-01-05]
• EMI (electromagnetic interference) – Degradation of the performance of an equipment,
transmission channel or system caused by an electromagnetic disturbance.
[IEC 60050-161:1990, 161-01-06]
• Recovered heat – Thermal energy that has been recovered for useful purposes.
• Waste heat – Thermal energy released and not recovered.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
air bleed
introduction of small levels of air (around 5 %) into the fuel stream, upstream of the fuel inlet
to the fuel cell (3.43) or fuel cell stack (3.50) or within the anode (3.2) compartment
NOTE The purpose of air bleed is to mitigate poisoning by species such as carbon monoxide by catalytic
oxidation of the poison within the anode (3.2) compartment of the fuel cell (3.43).
3.2
anode
electrode (3.33) at which the oxidation of the fuel takes place
[IEC 60050-482:2004, 482-02-27, modified]

TS 62282-1 © IEC:2010 – 9 –
3.3
active layer
See catalyst layer (3.14).
3.4
area
3.4.1
cell area
geometric area of the bipolar plate (3.9) perpendicular to the direction of current flow
NOTE The cell area is expressed in m .
3.4.2
electrode area
3.4.2.1
active area
geometric area of the electrode (3.33) perpendicular to the direction of the current flow
NOTE 1 The active area is expressed in m .
NOTE 2 The active area, also called effective area is used in the calculation of the cell current density (3.26).
3.4.2.2
effective area
See active area (3.4.2.1).
3.4.2.3
electrochemical surface area
area of the electrochemically accessible electrocatalyst (3.31) surface
NOTE The electrochemical surface area is expressed in m .
3.4.3
membrane electrode assembly (MEA) area
geometric area of the entire MEA (3.73) perpendicular to the direction of net current flow,
including active area (3.4.2.1), and uncatalysed areas of the membrane
NOTE The membrane electrode assembly (MEA) area is expressed in m .
3.4.4
specific surface area
area of an electrocatalyst (3.31) accessible to reactants due to its open porous structure or
electrochemical surface area (3.4.2.3) per unit mass (or volume) of the catalyst (3.11)
2 2 3
NOTE The specific surface area is expressed in m /g, m /m .
3.5
availability factor
ratio of the up duration to the period of time under consideration
[IEC 60050-603:1986, 603-05-09]
3.6
axial load
compressive load applied to the end plates (3.40) of a fuel cell stack (3.50) to assure contact
and/or gas tightness
NOTE The axial load is expressed in Pa.

– 10 – TS 62282-1 © IEC:2010
3.7
balance of plant
BOP
supporting/auxiliary components based on the power source or site-specific requirements and
integrated into a comprehensive power system package
NOTE In general, all components besides the fuel cell stack (3.50) or fuel cell module (3.48) and the fuel
processing system are called balance of plant components.
3.8
base load operation
See full load operation (3.77.4).
3.9
bipolar plate
conductive plate separating individual cells in a stack, acting as current collector (3.25) and
providing mechanical support for the electrodes (3.33) or membrane electrode assembly
(3.73)
NOTE The bipolar plate usually incorporates flow field on either side for the distribution of reactants (fuel and
oxidant) and removal of products, and may also contain conduits for heat transfer. The bipolar plate provides a
physical barrier to avoid mixing of oxidant, fuel and coolant fluids. The bipolar plate is also known as the bipolar
separating plate.
3.10
bus bar
See stack terminal (3.105).
3.11
catalyst
substance that accelerates (increases the rate of) a reaction without being consumed itself
See also electrocatalyst (3.31).
NOTE The catalyst lowers the activation energy of the reaction, allowing for an increase in the reaction rate.
3.12
catalyst coated membrane
CCM
(in a PEFC (3.43.6)) membrane whose surfaces are coated with a catalyst layer (3.14) to form
the reaction zone of the electrode (3.33)
See also membrane electrode assembly (MEA) (3.73).
3.13
catalyst coated substrate
CCS
substrate whose surface is coated with a catalyst layer (3.14)
3.14
catalyst layer
surface adjacent to either side of the membrane containing the electrocatalyst (3.31), typically
with ionic and electronic conductivity
NOTE The catalyst layer comprises the spatial region where the electrochemical reactions may take place.

TS 62282-1 © IEC:2010 – 11 –
3.15
catalyst loading
amount of catalyst (3.11) incorporated in the fuel cell (3.43) per unit active area (3.4.2.1),
specified either per anode (3.2) or cathode (3.18) separately, or combined anode and
cathode loading
NOTE The catalyst loading is expressed in g/m .
3.16
catalyst poisoning
inhibition of the catalyst (3.11) properties by substances (poisons)
NOTE Electrocatalyst (3.31) poisoning causes degradation of the fuel cell (3.43) performance.
3.17
catalyst sintering
binding together of catalyst (3.11) particles due to chemical and/or physical processes
3.18
cathode
electrode (3.33) at which the reduction of the oxidant takes place
[IEC 60050-482:2004, 482-02-28, modified]
3.19
cell(s)
3.19.1
planar cell
fuel cell (3.43) formed in a flat structure
3.19.2
single cell
basic unit of a fuel cell (3.43) consisting of a set of an anode (3.2) and a cathode (3.18)
separated by electrolyte (3.34)
3.19.3
tubular cell
fuel cells (3.43) with a cylindrical structure that allows fuel and oxidant to flow on the inner or
outer surface of the tube
NOTE Different cross section types can be used (e.g. circular, ellipse).
3.20
compression end plate
See end plate (3.40).
3.21
conditioning
(related to cells/stacks) preliminary step that is required to properly operate a fuel cell (3.43)
and that is realized following a protocol specified by the manufacturer
NOTE The conditioning may include reversible and/or irreversible processes depending on the cell technology.
3.22
cross leakage
See crossover (3.23).
– 12 – TS 62282-1 © IEC:2010
3.23
crossover
leakage between the fuel side and the oxidant side, of a fuel cell (3.43), in either direction,
generally through the electrolyte (3.34)
NOTE Crossover is also called cross leakage.
3.24
current
3.24.1
leakage current
electric current in an unwanted conductive path other than a short-circuit
NOTE The leakage current is expressed in A.
[IEC 60050-151:2001, 151-15-49]
3.24.2
rated current
maximum continuous electric current as specified by the manufacturer, at which the fuel cell
power system (3.49) has been designed to operate
NOTE The rated current is expressed in A.
3.25
current collector
conductive material in a fuel cell (3.43) that collects electrons from the anode (3.2) side or
conducts electrons to the cathode (3.18) side
3.26
current density
current per unit active area (3.4.2.1)

2 2
NOTE The current density is expressed in A/m or A/cm .
3.27
degradation rate
rate at which a cell’s performance deteriorates over time
NOTE The degradation rate can be used to measure both recoverable and permanent losses in cell performance.
The typical unit of measure is volts (DC) per unit time or % of initial value (volt DC) per a fixed time.
3.28
desulfurizer
reactor to remove sulfur components contained in raw fuel (3.89)
NOTE Adsorbent desulfurizer, catalytic hydro-desulfurizer, etc.
3.29
differential cell pressure
difference in pressure across the electrolyte (3.34) as measured from one electrode (3.33) to
the other
NOTE The differential cell pressure is expressed in Pa.
3.30
efficiency
ratio of output useful energy flows to input energy flows of a device
NOTE The energy flows can be measured by measuring the relevant in and output values over one single defined
time interval, and can, therefore, be understood as mean value of the respective flows.

TS 62282-1 © IEC:2010 – 13 –
3.30.1
electrical efficiency
ratio of the net electrical power (3.85.3) produced by a fuel cell power system (3.49) to the
total enthalpy flow supplied to the fuel cell power system
NOTE Lower heating value (LHV) is assumed unless otherwise stated.
3.30.2
exergetic efficiency
ratio of the net electrical power (3.85.3) produced by a fuel cell power system (3.49) and the
total exergy flow supplied to the fuel cell system assuming gaseous reaction products
3.30.3
heat recovery efficiency
ratio of recovered heat flow of a fuel cell power system (3.49) and the total enthalpy flow
supplied to the fuel cell power system
NOTE The supplied total (including reaction enthalpy) enthalpy flow of the raw fuel (3.89) should be related to
lower heating value (LHV) for a better comparison with other types of energy conversion systems.
3.30.4
overall energy or total thermal efficiency
ratio of total useable energy flow (net electrical power (3.85.3) and recovered heat flow) to the
total enthalpy flow supplied to the fuel cell power system (3.49)
NOTE The supplied total (including reaction enthalpy) enthalpy flow of the raw fuel (3.89) should be related to
lower heating value (LHV) for a better comparison with other types of energy conversion systems.
3.30.5
overall exergy efficiency
ratio of the sum of net electrical power (3.85.3) and total useable exergy flow of recovered
heat related to the total exergy flow supplied to the fuel cell power system (3.49)
NOTE The supplied total exergy flow of the raw fuel (3.89) (including reaction) should be related to a gaseous
product for a better comparison with other types of energy conversion systems.
3.31
electrocatalyst
substance that accelerates (increases the rate of) an electrochemical reaction
See also catalyst (3.11).
NOTE In a fuel cell (3.43), electrocatalysts are placed in the active (3.3) or catalyst layer (3.14).
3.32
electrocatalyst support
component of an electrode (3.33) that is the support of the electrocatalyst (3.31), and serves
as the conductive medium
3.33
electrode
an electronic conductor (or semi-conductor) through which an electric current enters or leaves
the electrochemical cell as the result of an electrochemical reaction
NOTE An electrode (3.33) may be either an anode (3.2) or cathode (3.18).
3.33.1
gas diffusion electrode
component on the anode (3.2) or cathode (3.18) side comprising all electronic conductive
elements of the electrode (3.33), i.e. gas diffusion layer (3.57) and catalyst layer (3.14)

– 14 – TS 62282-1 © IEC:2010
3.33.2
ribbed electrode
electrode (3.33) provided with grooves on the electrode substrate for gas passage
3.34
electrolyte
liquid or solid substance containing mobile ions that render it ionically conductive
[IEC 60050-111:1996, 111-15-02]
NOTE The electrolyte is the main distinctive feature of the different fuel cell (3.43) technologies (e.g. a liquid,
polymer, molten salt, solid oxide) and determines the useful operating temperature range.
3.35
electrolyte leakage
undesired escape of liquid electrolyte (3.34) from a fuel cell stack (3.50)
3.36
electrolyte loss
any decrease with respect to the initial electrolyte (3.34) inventory of a fuel cell (3.43)
NOTE The electrolyte (3.34) losses may originate by different processes such as evaporation, leakage, migration
and consumption in metallic component corrosion.
3.37
electrolyte matrix
insulating gastight cell component with a properly tailored pore structure that retains the liquid
electrolyte (3.34)
NOTE The pore structure has to be adjusted with respect to those of the adjacent electrodes (3.33) to assure a
complete filling (3.41).
3.38
electrolyte migration
potential driven effect experienced by external manifolded MCFC (3.43.4) stacks
NOTE The electrolyte (3.34) tends to migrate from the positive end of the stack to the negative end. The
migration occurs through the gaskets placed between the external manifolds (3.70) and the stack edges.
3.39
electrolyte reservoir
component of liquid electrolyte fuel cells (3.43) (e.g. MCFC (3.43.4) and PAFC (3.43.5)) that
stores liquid electrolyte (3.34) for the purpose of replenishing electrolyte losses (3.36) over
the cell life (3.69.2)
3.40
end plate
component located on either end of the fuel cell stack (3.50) in the direction of current flow,
serving to transmit the required compression to the stacked cells
NOTE The end plate may comprise ports, ducts, manifolds (3.70), or clamping plates for the supply of fluids
(reactants, coolant) to the fuel cell stack (3.50). May also be known as stack end frame or compression end plate.
3.41
filling (level)
fraction of the total open pore volume of a fuel cell (3.43) porous component (e.g. electrode
(3.33) or electrolyte matrix (3.37)) that is occupied by a liquid electrolyte (3.34)

TS 62282-1 © IEC:2010 – 15 –
3.42
flow configuration of stack or module
3.42.1
co-flow
fluid flow in same parallel directions through adjacent parts of an apparatus, as in a heat
exchanger or in a fuel cell (3.43)
NOTE This flow configuration can be adopted, for example, in internally manifolded fuel cell stack (3.50) for the
oxidant and the fuel gas streams.
3.42.2
counter flow
fluid flow in opposite parallel directions through adjacent parts of an apparatus, as in a heat
exchanger or in a fuel cell (3.43)
NOTE This flow configuration can be adopted, for example, in an internally manifolded fuel cell stack (3.50) for
the oxidant and the fuel gas streams.
3.42.3
cross flow
fluid flow going across another flow at an angle essentially perpendicular to one another
through adjacent parts of an apparatus, as in a heat exchanger or a fuel cell (3.43)
NOTE This is the fluid flow configuration of choice for an externally manifolded fuel cell stack (3.50) for the
oxidant and the fuel gas streams.
3.42.4
dead end flow
cell or stack configuration, characterized by the lacking of a fuel and/or oxidant outlet port
NOTE In dead end operation, almost 100 % of the reactant fed to the cell or stack is consumed. A small fraction
of reactants may be vented out from fuel cell power systems (3.49) that require periodic purging of the electrode
(3.33) compartment(s).
3.43
fuel cell
electrochemical device that converts the chemical energy of a fuel and an oxidant to electrical
energy (DC power), heat and reaction products
[IEC 60050-482:2004, 482-01-05, modified]
NOTE The fuel and oxidant are typically stored outside of the fuel cell and transferred into the fuel cell as they
are consumed.
3.43.1
alkaline fuel cell
fuel cell (3.43) that employs an alkaline electrolyte (3.34)
3.43.2
direct fuel cell
fuel cell (3.43) in which the raw fuel (3.89) supplied to the fuel cell power system (3.49) and
the fuel supplied to the anodes (3.2) is the same
3.43.3
direct methanol fuel cell
DMFC
direct fuel cell (3.43.2) in which the fuel is methanol (CH OH), in gaseous or liquid form
NOTE The methanol is oxidized directly at the anode (3.2) with no reformation to hydrogen. The electrolyte (3.34)
is typically a proton exchange membrane.

– 16 – TS 62282-1 © IEC:2010
3.43.4
molten carbonate fuel cell
MCFC
fuel cell (3.43) that employs molten carbonate as the electrolyte (3.34)
NOTE Usually, either molten lithium/potassium or lithium/sodium carbonate salts are used as the electrolyte
(3.34).
3.43.5
phosphoric acid fuel cell
PAFC
fuel cell (3.43) that employs aqueous solution of phosphoric acid (H PO ) as the electrolyte
3 4
(3.34)
3.43.6
polymer electrolyte fuel cell
PEFC
fuel cell (3.43) that employs a polymer with ionic exchange capability as the electrolyte (3.34)
NOTE The polymer electrolyte fuel cell is also called a proton exchange membrane fuel cell (PEMFC) (3.43.7)
and solid polymer fuel cell (SPFC).
3.43.7
proton exchange membrane fuel cell
PEMFC
See polymer electrolyte fuel cell (PEFC) (3.43.6).
3.43.8
regenerative fuel cell
electrochemical cell able to produce electrical energy from a fuel and an oxidant, and to
produce the fuel and oxidant in an electrolysis process from electrical energy
3.43.9
solid oxide fuel cell
SOFC
fuel cell (3.43) that employs an ion-conducting oxide as the electrolyte (3.34)
3.43.10
solid polymer fuel cell
SPFC
See polymer electrolyte fuel cell (3.43.6).
3.44
fuel cell / battery hybrid system
fuel cell power system (3.49) combined with a battery, for delivering useful electric power
NOTE The fuel cell power system (3.49) can deliver electric power, charge the battery, or both. The system can
deliver and accept electric energy.
3.45
fuel cell / gas turbine system
power system based on the integration of a high temperature fuel cell (3.43), usually MCFC
(3.43.4) or SOFC (3.43.9), and a gas turbine
NOTE The system operates by using the fuel cell’s thermal energy and residual fuel to drive a gas turbine. Also
known as a fuel cell/gas turbine hybrid system.
3.46
fuel cell gas turbine hybrid system
See fuel cell / gas turbine system (3.45).

TS 62282-1 © IEC:2010 – 17 –
3.47
fuel cell cogeneration system
fuel cell power system (3.49) that is intended to supply both electrical power and heat to an
external user
3.48
fuel cell module
assembly incorporating one or more fuel cell stacks (3.50) and other main and, if applicable,
additional components, which is intended to be integrated into a power plant or a vehicle
NOTE A fuel cell module is comprised of the following main components: one or more fuel cell stack(s) (3.50),
piping system for conveying fuels, oxidants and exhausts, electrical connections for the power delivered by the
stack(s) and means for monitoring and/or control. Additionally, a fuel cell module may comprise: means for
conveying additional fluids (e.g. cooling media, inert gas), means for detecting normal and/or abnormal operating
conditions, enclosures or pressure vessels and module ventilation systems.
3.49
fuel cell power system
generator system that uses a fuel cell module(s) (3.48) to generate electric power and heat
NOTE A fuel cell power system is composed of all or some of the systems shown in Clause 2.
3.49.1
micro fuel cell power system
micro fuel cell power unit (3.74) and associated fuel cartridges that is wearable or easily
carried by hand
3.49.2
portable fuel cell power system
fuel cell power system (3.49) that is not intended to be permanently fastened or otherwise
secured in a specific location
3.49.3
stationary fuel cell power system
fuel cell power system (3.49) that is connected and fixed in place
3.50
fuel cell stack
assembly of cells, separators, cooling plates, manifolds (3.70) and a supporting structure that
electrochemically converts, typically, hydrogen rich gas and air reactants to DC power, heat
and other reaction products
3.51
fuel cell vehicle
electric vehicle using a fuel cell power system (3. 49) to feed an electric motor for propulsion
3.52
fuel utilization
ratio of the fuel that is electrochemically converted to generate the cell current to the total
amount of the fuel entering the cell
3.53
fuelling coupler
interface that connects a fuel cell vehicle (3.51) and a fuel supply service station
NOTE The fuelling coupler may also supply cooling water and communication information relating to fuel supply.
The fuel coupler consists of the fuelling nozzle and the fuelling receptacle.

– 18 – TS 62282-1 © IEC:2010
3.54
gas cleanup
removal of contaminants from gaseous feed streams by a physical or chemical process
3.55
gas diffusion anode
See gas diffusion electrode (3.33.1).
3.56
gas diffusion cathode
See gas diffusion electrode (3.33.1).
3.57
gas diffusion layer
GDL
porous substrate placed between the catalyst layer (3.14) and the bipolar plate (3.9) to serve
as electric contact and allow the access of reactants to the catalyst layer and the removal of
reaction products
NOTE The gas diffusion layer is also called a porous transport layer (PTL).
3.58
gas leakage
sum of all gases leaving the fuel cell module (3.48) except the intended exhaust gases
3.59
gas purge
protective operation to remove gases and/or liquids, such as fuel, hydrogen, air or water, from
a fuel cell power system (3.49)
3.60
gas seal
airtight mechanism that prevents the reaction gas from leaking out of a prescribed flow path
NOTE The gas seal may be dry or wet, depending on the fuel cell (3.43) type.
3.61
heat rate
inverse ratio of electrical efficiency (3.30.1)
3.62
humidification
process of introducing water into the fuel cell (3.43) with the fuel and/or oxidant reactant gas
stream(s)
3.63
humidifier
equipment for adding water to the fuel and/or oxidant gas stream(s)
3.64
interconnector
conductive and gastight component connecting single cells (3.19.2) in a fuel cell stack
(3.50)
TS 62282-1 © IEC:2010 – 19 –
3.65
interface point
measurement point at the boundary of a fuel cell power system (3.49) at which material
and/or energy either enters or leaves
NOTE This boundary is intentionally selected to accurately measure the performance of the system. If
necessary, the boundary or the interface points of the fuel cell power system (3.49) to be assessed should be
determined by agreement of the parties.
3.66
internal resistance
ohmic resistance inside a fuel cell (3.43) caused by the electronic and ionic resistances
See ohmic polarization (3.82.2).
NOTE The term ohmic refers to the fact that the correlation between voltage drop and current obeys Ohm’s Law.
3.67
IR loss
ohmic polarization
See ohmic polarization (3.82.2).
3.68
land (related to flow field)
protruding structure in the flow field that is in contact with the gas diffusion layer (3.57) and
thereby providing electronic contact and, consequently, pathways for electron flow
3.69
life
3.69.1
catalyst life (reformer)
duration of the time interval between the instant of initial start-up of a fuel cell power system
(3.49) and the initial instant when the concentration of non-reformed fuel at the reformer
(3.92) outlet exceeds the manufacturers allowable design value, while the fuel cell power
system is operating at its ratings.
3.69.2
cell or stack life
duration of the time interval under operating conditions between the first start up and until the
fuel cell voltage, at a reference current, drops below the specified minimum acceptable
voltage
NOTE The minimum acceptable voltage value should be determined by agreement of the parties taking into
account the specific use.
3.70
manifold
conduit(s) which supplies fluid to or collects it from the fuel cell (3.43) or the fuel cell stack
(3.50)
NOTE 1 External manifold design refers to a stacking (3.106) of cells where the gas mixtures are supplied from a
central source to large fuel and oxidant inlets covering adjacent sides of the stack and sealed with properly
designed gaskets. The exhaust gases are collected on the opposite sides with similar systems.
NOTE 2 Internal manifold design refers to a system of ducts inside the stack and penetrating the bipolar plates
(3.9) that distributes the gas flows among the cells.
3.71
mass activity
See specific activity (3.102).

– 20 – TS 62282-1 © IEC:2010
3.72
mass transport (or concentration) loss
See concentration polarization (3.82.3).
3.73
membrane electrode assembly
MEA
component of a fuel cell (3.43), usually PEFC (3.43.6), DMFC (3.43.3), consisting of an
electrolyte membrane with gas diffusion electrodes (3.33.1) on either side
3.74
micro fuel cell power unit
fuel cell (3.43) based electric generator providing a DC output voltage (3.117.3) that does not
exceed 60 V and a continuous net electrical power (3.85.3) that does not exceed 240 VA
NOTE The micro fuel cell power unit does not include a fuel cartridge.
3.75
no load voltage
See open circuit voltage (3.117.2).
3.76
non-repeat parts
all the components of a fuel cell stack (3.50) that are not part of the repeated cell unit, e.g.
the stack end plates (3.40)
3.77
operation
3.77.1
constant current operation
mode when the fuel cell power system (3.49) is operated at a constant current
3.77.2
constant power operation
mode when the fuel cell power system (3.49) is operated at a constant output power within
the extents of its power generation capacity
3.77.3
constant voltage operation
mode when the fuel cell power system (3.49) i
...