The purpose of this SAE Information Report is to provide an overview of special requirements and practices in fuel cell vehicle thermal management. This document is primarily directed to fuel cell applications in motor vehicles.

This SAE Technical Information Report (TIR) provides test methods for evaluating hydrogen sensors when the hydrogen system integrator and/or vehicle manufacturer elect to use such devices on board their hydrogen vehicles, including hydrogen fuel cell electric vehicles (FCEV).

The tests described in 5.1 of this document are performance-based and were developed to assess hydrogen sensor metrological parameters. These tests were designed to accommodate a wide range of environmental and operating conditions based on different possible situations and sensor implementations within the vehicle. Section 5.2 covers supplemental electrical safety and physical stress tests. These are based upon standard tests developed for qualifying electrical and other components for use on vehicles and do not explicitly pertain to gas sensor metrological performance assessment. Since the use of on-board hydrogen sensors is not standardized or mandated, their implementation can vary greatly from vehicle to vehicle and among potential applications or functions. For example, an on-board sensor could be located in a relatively dry environment such as in the passenger compartment or in a “highly humidifed” environment, such as within the process exhaust from the fuel cell system. As this is a guidance document and not a standard, no specific application will be identified. Also, as a guidance document, no performance specification or pass/fail criteria will be defined. For this reason, the hydrogen system integrator and/or vehicle manufacturer need to determine which tests and associated test conditions are relevant for their application(s). Thus, it is the prerogative of the hydrogen system integrator and/or vehicle manufacturer to define specific test acceptance criteria necessary to achieve the required performance of their process control and protective systems within the vehicle. The sensor manufacturer or testing laboratory is to present results of each test to the hydrogen system integrator and/or vehicle manufacturer, who will then use the results to ascertain the suitability of a sensor technology for their application.

Electric and alternative fueled vehicles present different hazards for first and second responders than conventional gasoline internal combustion engines. Hydrogen vehicles (H2V) including Fuel Cell Vehicles (FCVs) involved in incidents may present unique hazards associated with the fuel storage and high voltage systems.

The electrical hazards associated with the high voltage systems of hybrid-electric vehicles and FCVs are already addressed in the parent document, SAE J2990. This Recommended Practice therefore addresses electric issues by reference to SAE J2990 and supplements SAE J2990 to address the potential consequences associated with hydrogen vehicle incidents and suggest common procedures to help protect emergency responders, tow and/or recovery, storage, repair, and salvage personnel after an incident has occurred. Industry design standards and tools were studied and where appropriate, suggested for responsible organizations to implement.

This document provides test methods for evaluating the maximum power of electrified vehicle powertrain systems by direct measurement at the drive wheel hubs or axles. Additional tests are included specifically for PHEVs to measure electric-only propulsion power and for HEVs to measure electric power assist and regenerative braking. The testing requires either a chassis or hub dynamometer for all driven wheels. Results are processed to provide fair and consistent comparisons of power capabilities among different designs of electrified powertrains. Tests can also be performed on conventional vehicles if precise comparisons to electrified vehicles are desired.

This standard specifies the communications hardware and software requirements for fueling hydrogen surface vehicles (HSV), such as fuel cell vehicles, but may also be used where appropriate, with heavy-duty vehicles (e.g., busses) and industrial trucks (e.g., forklifts) with compressed hydrogen storage. It contains a description of the communications hardware and communications protocol that may be used to refuel the HSV. The intent of this standard is to enable harmonized development and implementation of the hydrogen fueling interfaces.

This standard is intended to be used in conjunction with the hydrogen fueling protocols in SAE J2601 and nozzles and receptacles conforming with SAE J2600.

SAE J2579 is being developed by the SAE Fuel Cell Vehicle (FCV) Standards Committee to provide recommended practices for Fuel Systems in Fuel Cell and Other Hydrogen Vehicles. As part of this work, definitions for pressurized systems and containers were developed. The purpose of this document is to disseminate these definitions prior to the release of SAE J2579 such that other technical groups are aware of the information.

This document describes a test procedure for rating peak power of the Rechargeable Energy Storage System (RESS) used in a combustion engine Hybrid Electric Vehicle (HEV). Other types of vehicles with non fossil fuel primary engines, such as fuel cells, are not intended to use this test procedure.

This standard provides background information and a hydrogen fuel quality standard for commercial proton exchange membrane (PEM) fuel cell vehicles. This report also provides background information on how this standard was developed by the Hydrogen Quality Task Force (HQTF) of the Interface Working Group (IWG) of the SAE Fuel Cell Standards Committee.

This recommended practice is intended to serve as a design verification procedure and not a product qualification procedure. It may be used to verify design specifications or vendor claims. Test procedures, methods and definitions for the performance of the fuel processor subsystem (FPS) of a fuel cell system (FCS) are provided. Fuel processor subsystems (FPS) include all components required in the conversion of input fuel and oxidizer into a hydrogen-rich product gas stream suitable for use in fuel cells. Performance of the fuel processor subsystem includes evaluating system energy inputs and useful outputs to determine fuel conversion efficiency and where applicable the overall thermal effectiveness. Each of these performance characterizations will be determined to an uncertainty of less than ± 2% of the value.

The method allows for the evaluation of fuel processor subsystems for two general cases.

This document applies to all fuel processor subsystems for transportation applications regardless of fuel processor type, fuel cell type, electrical power output, thermal output, or system application (propulsion or auxiliary power unit (APU)). For example, the fuel processor subsystems associated with proton exchange, molten carbonate and solid oxide fuel cells can differ due to the requirements of the fuel cells themselves.

Performance of the fuel processor subsystem, and preprocessor if applicable, is evaluated. A stand alone fuel processor “system” or even the primary reactor (e.g., autothermal, partial oxidation or steam reforming reactor) of a fuel processor subsystem that would normally be integrated into a fuel cell system can be evaluated. The fuel processor together with the preprocessor (if required) converts the fuel (gasoline or other liquid hydrocarbon) to a reformate gas consisting largely of H₂, CO, CO₂, H₂O and N₂ (if air is used). After the fuel processor subsystem, reformate gas typically contains only trace levels of carbon bearing components higher than C₁. The FPS would be evaluated in a test facility that is designed to evaluate a stand-alone component rather than a portion of the reformer such as a specific catalyst or a particular vessel design.

Any fuel(s) mutually agreed to by the test parties can be used such as 1) straight run gasoline (EPA Fuel-CARB reformulated gasoline Tier II, 30 ppm sulfur), or 2) methanol or 3) hydrocarbon fuel such as iso-octane, naptha, diesel, liquefied natural gas (LNG) or LPG (propane), etc.

The procedures provide a point-in-time evaluation of the performance of the fuel processor subsystem. Steady state and transient (start-up and load-following) performance are included. Methods and procedures for conducting and reporting fuel processor testing, including instrumentation to be used, testing techniques, and methods for calculating and reporting results are provided. The boundary limits for fuel and oxidant input, secondary energy input and net energy output are defined. Procedures for measuring temperature, pressure, input fuel flow and composition, electrical power and thermal output at the boundaries are provided.

Procedures for determination of the FPS performance measures such as fuel processor efficiency and cold gas efficiency at a rated load or any other steady state condition are provided. Methods to correct results from the test conditions to reference conditions are provided.

SI units are used throughout the recommended practice document.

This recommended practice is intended to serve as a procedure to verify the functional performance, design specifications or vendor claims of any PEM (Proton Exchange Membrane) type fuel cell stack sub-system for automotive applications. In this document, definitions, specifications, and methods for the functional performance characterization of the fuel cell stack sub-system are provided. The functional performance characterization includes evaluating electrical outputs and controlling fluid inputs and outputs based on the test boundary defined in this document.

In this document, a fuel cell stack sub-system is defined to include the following:

Not included in the sub-system are the following: