Industry-Wide Light Duty Hydrogen Vehicle Fueling

Protocol up to 70MPa:

Created by Math Modeling and Confirmed by System Testing

Jesse Schneider, Ian Sutherland-GM, Mike Veenstra- Ford, Mark McDougall- Powertech Lab,

Andrea Lubawy- Toyota, Steve Mathison –Honda,Steffen Maus- Daimler, Frederic Barth- Air Liquide,

Bob Boyd- Linde, Julie Cairns-CSA

Outline

• Overview & Importance for common protocol

• SAE TIR J2601• SAE TIR J2601• Theory and Modeling• Testing• Implementation

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Importance of a Hydrogen Fueling Vehicle Protocol

Do you know how your vehicle is being filled with h ydrogen?

• Hydrogen fueling is critical to the success of a hydrogen economy.

• Customers expect a safe, short, and complete hydrogen fill

• Characteristics of hydrogen and limits of storage systems emphasize need for managing the safety of the fill.

• Need to maximize the capacity (state of charge) percentage of the fill.

• Hydrogen fueling is not yet standardized.

• Historically, protocols established through individual agreements between OEMs and station providers, isolated partnerships.

• As the industry progresses from hydrogen vehicle demonstrations to commercialization, an industry fueling protocol is needed for universal usage

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Importance of a Hydrogen Fueling Vehicle Protocol

The Challenge of Compressed Hydrogen Fueling

• Hydrogen fueling protocol must manage the heat of compression.

Storage tanks have a maximum temperature rating of 85 C

Pressurized gas entering the tank increases and temperature.

Hydrogen tank construction (i.e. wall thickness and material) reduces heat transfer which can influence the temperature increase in the tank.

• Hydrogen fueling protocol must manage unknowns.• Hydrogen fueling protocol must manage unknowns.

Non-communication fill:

Station must estimate the temperature change that occurs during fueling. Many tank unknowns: starting temperature, capacity, type, number of tanks, etc.

In some cases, the station estimates can be conservative resulting in a reduced state of charge fill.

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Known Unknown

pressure storage tank temperature

ambient temperature

Technical Goals for Compressed Hydrogen Fueling • Maintain the safety limits of storage system.

Maximum Gas Temperature: 85 C

Maximum Pressure: 87.5 MPa (70 MPa NWP) and 43.8 MPa (35 MPa NWP)

• Achieve target desired customer attributes.

Fueling Time: 3 minutes Ramp Rate (Type A Station)

Typical State of Charge Range : 90% to 100% (density based on NWP at 15 C)

Hydrogen Fueling Protocol Approach

Options for Compressed Hydrogen Fueling Protocol

• Vehicle to station interface strategies

Communication: vehicle provides tank parameters through an electrical interface

Non-communication: vehicle provides tank pressure only

• Station key control factors

Pre-cooling of hydrogen: station conditions H2 temperature prior to dispensing

Hydrogen delivery rate: station provides fill rate per mass or pressure vs. time

Fill termination: station determines end pressure and/or density that meets goals5

SAE J2601TIR Status and Future TIR Status and Future Standardization Goals

SAE TIR J2601• V.1 Technical Information

Report (TIR): Light Duty Vehicle H2 Fueling

• Provides guidance for hydrogen fueling within reasonable time without exceeding temperature and exceeding temperature and pressure limits

• Provides pressure targets to achieve a reasonable state of charge (SOC) under diverse ambient temperature(s)

• Fueling protocol created from fueling actual OEM tanks under extreme conditions

• V.2: Residential & Bus Fueling (July Start Date)

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SAE J2601 & CSA 4.3

SAE J2601Vehicle Limits & Targets

- Non-Communication Tables- Communications

CSA 4.3Dispenser Confirmation

- Testing Device- Test Procedure

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J2601 Overview

• Definition of Fueling Station Types• Common Procedures for Hydrogen Fueling

– Non-Communication Fueling Tables– Communication Fueling Guidance

• CSA 4.3 Performance Tests to Verify Dispenser Performance with J2601 Fueling Protocols

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Fueling Station Types

J2601 defines fueling station type by capability to dispense hydrogen fuel at a specific nozzle “pre-cooled temperature”:

• Type “A”- Station has -40 ̊ C pre-cooling• Type “A”- Station has -40 ̊ C pre-cooling

• Type “B”- Station has -20 ̊ C pre-cooling

• Type “C”- Station has 0 ̊ C pre-cooling

• Type “D”- Station has no pre-cooling

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J2601 Fueling Procedure Summary

CommunicationSignal?

Start

No YesFueling Station Type

Ambient Temperature

Vehicle MeasurementsHSS Initial Pressure P0

HSS Capacity

Vehicle MeasurementsHSS Initial Pressure P0

HSS Capacity

Fueling Station Type

Vehicle Data

Vehicle Data

Validity Check

Lookup Tables - A, B, C, or DAverage Pressure Ramp Rate (APRR)Fueling Target Pressure Ptarget

Fuel WhilePstation< Ptarget - ∆Pstation

End

While Vehicle Data Received

Fuel While Passes Validity Check and:Vehicle command ≠ Abort

Pvehicle < 125% NWP

Tvehicle < 85°C

Pstation < 125% NWP - ∆Pstation

Pstation < 110% Ptarget - ∆Pstation

SOCstation < 100% - ∆SOCstation

End

if data lost

or not plausible

Gray box – station only Blue box - vehicle interaction 11

Lookup Tables - A, B, C, or D (guideline)Average Pressure Ramp Rate (APRR)

Pas

s

HSS P0

HSS CapacityFail

Gaseous Hydrogen Fueling:Theory and ModelingTheory and Modeling

Fueling Fundamentals

An optimal fueling protocol will …

• fuel all hydrogen storage systems quickly to a high state of charge (SOC)

• never violate the storage system operating limits of 85°C internal tank temperature (don’t overheat) or 100% SOC (don’t overfill)

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Parameter Example – Hot Soak / Cold Soak

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• Vehicle storage system characteristics

• Vehicle tank internal temperature

• Vehicle storage system volume

• Vehicle tank / storage system pressure

• Station ambient temperature

Non-communication Communication

station does not know

station does not know vehicle tells station

station measures vehicle tells station

station measures vehicle tells station

station measures

station does not know

station measures

Fueling Parameter

Protocol Development – Key Parameters

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• Station fuel delivery temperature

• Fueling rate

• Fueling final pressure

station characteristic

station control

station control

station characteristic

station control

station control

• Two fueling cases: 1) non-communication and 2) comm unication

• Protocol is based on known parameter values and pos sible ranges of unknown parameter values

• Protocol specifies fueling rate and final fill pres sure as a function of known parameter values

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Non-Communication Case Protocol Development

Step 1 – Fueling Rate• Fast fueling is desired, but 85°C tank internal te mperature limit must not

be violated under any fueling conditions– Assign boundary values to all unknown parameters such that “hot case fueling” occurs.

(e.g. hot ambient soak, start from empty, large single tank, composite liner, etc.)

– Run math model to find the fastest fueling rate that will not overheat tank

Step 2 – Target Pressure• A full fill is desired, but 100% SOC must not be violated in any fueling

conditions• A full fill is desired, but 100% SOC must not be violated in any fueling

conditions– Assign boundary values to all unknown parameters such that “cold case fueling” occurs.

(e.g. cold ambient soak, defueling effect, small tank(s), metal liner, etc.) “Cold case” results in highest possible SOC for a given final fueling pressure

– Apply fueling rate from Step 1

– Run math model to find highest target pressure that will not overfill storage system

Step 3 – SOC Assessment• Range of SOCs expected in real-world application of fueling protocol is

xx-100%

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tem

p

Start fueling

Endfueling

Hot case vehicle defines average pressure ramp rate

Hot soak = 20°C

Look-up Table Development - Example

Hot case vehicleType IV large tank - park and hot soak, then fuel from empty

?? MPa/min

P = 2MPa

fuel temp-35C

Step �

Ptarget (??% SOC)

Worst-case SOC

Step �

Ambient temp (station) = 0°C

time

Cold case vehicle defines target pressure

Cold case vehicleType III small tank – cold soak followed

by rapid defuel, then fuel from Pinitial

Ptarget (100% SOC)

P = 2MPa

fuel temp-40C

+20

°C

Cold soak = -10°C-10°

C

P = 2MPa

Step �

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Modeling Results

Non-communication Case• A series of “look-up tables” that specify fueling rate and target pressure

as a function of ambient temperature, initial tank pressure and storage system volume

• Look-up table values describe the capabilities and limitations of the fueling process. For example– Fueling times of 3-5 minutes or less under most conditions when fuel pre-cooled to -40°C

– Fueling times of an hour or longer under some conditions when station does not have pre-cooling capability

– Expected SOCs in the 90-100% range

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Modeling ResultsCommunication Case

• A series of “look-up tables” that provide a recommended initial fueling rate as a function of initial tank temperature, initial tank pressure, and storage system volume

• In general, faster fueling is possible in communication case where tank internal temperature is known to station

– Fueling time of 3 minutes or less under most conditions when fuel pre-cooled to -40°C

– Fueling times of 3-20 minutes under most conditions when fuel pre-cooled to -20°C

– Under Moderate ambient temperatures, pre-cooling not always needed with – Under Moderate ambient temperatures, pre-cooling not always needed with communications.

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Fueling Data Driven Standard

Hydrogen Fueling Data Sets:• Exploration of “Range of Fueling”

– 70MPa Multi-Client Fast Fill Study– Used to generate models– Used to generate models

• Confirmation of “Look up Tables”– SAE J2601 Confirmation SOW– Use to confirm model outputs

Range of Fueling Conditions

70MPa Multi-Client Study Purpose:

• determine 70 MPa fueling targets meant to be utilized by Codes and Standards development organizations for the purpose of future guidelines and standards

• Determine the 70 MPa fueling parameters for each OEM fuel

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• Determine the 70 MPa fueling parameters for each OEM fuel system for modeling and station algorithm development

Funding Participants Include:Air Liquide, BP, Nippon Oil, Sandia, US DOE, Shell, Iwatani

Vehicle OEM Participants Include:Daimler, Chrysler, Ford, GM, Nissan, Toyota

Status: Completed

70MPa Multi-Client Study

Range of Fueling Conditions

Observations:

• Level of required pre-cooling is dependent on tank type

• Required pre-cooling is a linear function with initial tank temperature

Confirmation of Look-Up TablesSAE J2601 Confirmation SOW

Purpose:• experimentally confirm the 35 and 70 MPa fueling targets

included in the SAE J2601 look-up tables• experimentally confirm the tests to be included in CSA HGV4.3 –

Fueling Station Safety Parameter Evaluation

Scope of Work examines three distinct areas of interest:

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Scope of Work examines three distinct areas of interest:1. Over-density fueling

• Testing with cold-soak and cooling from driving on Type 3 tanks2. Over-temperature fueling

• Testing with hot-soak conditions on Type 4 tanks3. Target SoC fueling

• Testing with “normal” conditions on all tanks to confirm non-communication SoC

Status: Scope of Work submitted to DOE and NREL

Look-up table confirmation. Preliminary tests to be performed by Powertech Lab to obtain base-level data.

Test 1 – Over-Density:• 70MPa, Type3, 1.4kg tank, ambient of 40C, initial pressure 20MPa, -

40PC, <6kg case• Resulting SoC was 99.8% ()

Test 2 – Over-Density:• 35MPa, Type3, 1.0kg tank, ambient of 40C, initial pressure 10MPa, -

Confirmation of Look-Up TablesSAE J2601 Confirmation SOW

• 35MPa, Type3, 1.0kg tank, ambient of 40C, initial pressure 10MPa, -20PC

• Resulting SoC was 95.3% (*)Test 3 – Target SoC:

• 70MPa, Type3, 1.4kg tank, ambient of 30C, initial pressure 15 MPa, -40PC, <6kg

• Resulting SoC was 91.7% (Minimum - 89%)Test 4 – Target SoC:

• 70MPa, Type3, 1.4kg tank, ambient of 40C, initial pressure 15MPa, -40PC, >6kg case

• Resulting SoC was 92.0% (Minimum 91%)

Implementation of J2601

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ImplementationDemonstration

• Light Duty Vehicles Implementation in stations (by mid-2010)

Required by CA Air Resources Board latest co-funding solicitation

Utilized by OEMs, CaFCP, etc.

• Field OEMs data from 2601 stations to be brought to SAE Team (until mid-2011)

Additional validation of performance, adjustments if necessary

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Standardization• J2601 planned to be standardized by end 2011

J2601

Communication Non-Communication

Use Specified Look-Up Table

Demonstrate Equivalent Performance or Better

Use Specified Look-Up TableOR

AND

ImplementationTesting of Hydrogen Stations : CSA 4.3 (by end 2009)

• Test procedures to confirm dispenser performance within limits and targets specified in J2601

• Hydrogen Dispenser Test Apparatus (HDTA) will be a mobile device with equipped with instrumented representative tanks to evaluate performance of dispenser

35 MPa

Tank Type Tank Size

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70 MPa

Tank Type Tank Size

Type III 1 kg

Type IV 3 kg

Tank Type Tank Size

Type III 1.4 kg

Type IV 4.7 kg

Type IV 9.8 kg

Document Status• SAE TIR J2601 V.1

– currently undergoing final testing– document target release July, 2009

– Goal:• Utilize TIR in the field as the dispenser specification for stations

to support ZEV fleets in US, ASIA, Europe, etc. similar to J2719to support ZEV fleets in US, ASIA, Europe, etc. similar to J2719

• SAE J2601 V.2 – include Residential & Bus Fueling– initiation July 14, 2009 at SAE Headquarters in Troy,MI

• CSA 4.3– document target release December, 2009

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Questions ?

J2601 Contact: Schneider.Jesse@web.de

Backup Slides

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2601 Overview

Process Flow For Non-Communications Fueling

Ambient temperature as measured by station(outside in the shade)

Station cooling capability rating(-40C, -20C, …)

Target fuel delivery

Pressure ramp rate (fill time) f(ambient temp, tank press, tank capacity )

Fueling protocol

Station pre-conditioning

Vehicle fueling

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Target fuel delivery temperature and tolerance

Vehicle tank pressure and capacity as measured by station

Target end pressure f( ambient temp, tank press, tank capacity )

Fueling protocol lookup tables

SAE J2601 Confirmation TestsTarget SoC Test

SAE J2601 Confirmation TestsTarget SoC Test

SAE J2601 Confirmation TestsOver-Density Test

SAE J2601 Confirmation TestsOver-Density Test

70 MPa Fueling Specification for Hydrogen Stations prior to release of

SAE J2601 (now superseded)

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