06213 Hydrogen Fuel Cell Test Station Preliminary Design

06213 – Hydrogen Fuel Cell Test Station Preliminary Design Review February 24 th, 2006

Group Members • Team Leader: Chad Byler (ME) • Mechanical Press & Fuel Flow: Dan Upton (ME), Brian Holzberger (ME), & Sean Ashman (ME) • Electrical Sensors & Power Supply: Dennis Farley (EE) & Steve Yang (EE) • Data Acquisition & Software: Shan Hu (CE) • Process and Safety: Corey Reynolds (ISE) Project Mentor: Dr. Bailey(ME)

Project Sponsor • Nanopower Research Laboratory http: //www. rit. edu/~physics/Research/nanopower. shtml – Funding • Dr. Rafaelle – Department of Physics at RIT – Customer Contact • Cory Cress – Ph. D student in Microsystems

Subsystem Topics • • • Layering of Fuel Cell Mechanical Assembly Process Heating of the Fuel Cell Humidification of gas Exhaust/Back Pressure Control Electrical Sensors and Power Supply Heating elements Layout of program logic Data Acquisition Budget But First…

Fuel Cell Operation Porous gas diffusion layer 2 e- Cathode = gas diffusion Anode = gas diffusion layer + catalyst layer Reaction Products (H 2 O only) Air/O 2 Porous gas diffusion layer H+ion + catalyst layer Thin solid hydrated Membrane as an Electrolyte proton H 2 O 2 Cathode Reactions: Anode Reactions: 1/2 O 2 + 2 e- O-2 ion H 2 2 H+ + O-2 ion H 2 O 2 H+ + 2 e- Catalyst Layers Active Material: Platinum or Platinum/Ruthenium PEM = Low temperature (80 o. C) hydrogen fuel cell with polymer electrolyte and precious metal electrodes

Location - Fuel Cell Assembly

Electrode Plate –Raised center portion to ensure maximum pressure of electrode with nano-tube catalyst. –Three different sizes for reaction area.

Fuel Cell Assembly PEM Nano-tube catalyst

Fuel Cell Stack

Location - Fuel Cell Assembly

Mechanical Assembly • Ease of Operation • Backing Plate rotates to allow assembly on horizontal surface. • Pegs hold fuel cell assembly in place until it can be compressed. • Repeatability • Use of power screw in combination with a pressure sensor or a torque wrench will allow for a repeatable mechanical pressure applied to the fuel cell. • The use of the mechanical assembly gives the ability to encapsulate the fuel cell and regulate the temperature.

Mechanical Assembly Animation

Power Screw Calculations Internal Pressure 120 psi Surface Area 2. 64 in^2 Max Force 316. 8 lb tan(l) must be less than the coefficient of friction in order to be postitive locking Screw Type: 1/2" - 10 Lead Root Dia. L= 0. 1 in Dr= 0. 45 in tan(l)=L/(p*Dr) tan(l)= 0. 071 m= 0. 3 Coefficient of friction steel to steel tan(l) < m, therefore the screw is self locking T=F*Dr/2*((L+p*m*Dr)/(p*Dr-m*L) T= 26. 999 T= 2. 25 Lb/in Lb/ft

Location - Fuel Cell Heating

Fuel Cell Heating

Steady-State Temperature Distribution without Insulation (O 2 side) -Shows need for cell Insulation -With insulation all cell components reach 80°C at S. S.

Location - Humidification

Gas Humidification Method • H 2 or O 2 inlet in base • Bubble up through water • Temperature of water controls the humidity of exit gas • Resistive heater used to heat water • Water temperature monitored to ensure safe heating

Expansion Valve Contains: • Pressure Sensor • Humidity Sensor • Temperature Sensor Pros: • Interchangeable • Non-Intrusive to flow

Location – Back Pressure

Exhaust/Pressure Regulation • Constant Upstream Pressure • Bleeds overpressure • Ability to dry PEM • Bubbles prove flow • Water seal provides no upstream airflow

Overview Schematic

Important Sensor Parameters • National Semiconductor LM 34 Temperature Sensor: – – – Maximum Current Draw: 90μA Maximum Output Current: 160μA Maximum Output Voltage: 6 V Accuracy: 0. 555°C Operating range: -45°C to 150°C • Honeywell HIH-3610 Humidity Sensor: – – – Maximum Current Draw: 200μA Maximum Output Current: 100μA Maximum Output Voltage: 3. 9 V Accuracy: 2% Relative Humidity Operating Range: 0 to 100% Relative Humidity in -40°C to 85°C

Important Sensor Parameters Cont. • Honeywell ASDX 100 G 24 R Gas Pressure Sensor : – – – Maximum Current Draw: 10 m. A Maximum Output Current: 2 m. A Maximum Output Voltage: 5 V Accuracy: 2% of Operating range: 0 to 100 PSI in 0°C to 85°C • Honeywell TD 4 A Liquid Temperature Sensor: – – – Maximum Current Draw: 26. 3 m. A Maximum Output Current: 1 m. A Maximum Output Voltage: 2. 5 V Accuracy: 1°C Operating Range: -40°C to 150°C

Worst Case Analysis Maximum Current Draw: • For Heaters: 0. 83 A maximum per heater * 3 = 2. 5 A maximum • For LM 34 Temperature Sensors: 90μA * 3 = 270μA • For HIH-3610 Humidity Sensors: 200μA * 2 = 400μA • For ASDX 100 G 24 R Gas Pressure Sensor: 10 m. A * 2 = 20 m. A • For Underwater Temp Sensor: 26. 3 m. A * 3 = 78. 9 m. A • Total Current Draw = 2. 51056 A

Heater Analysis • 58200 Joules are needed to heat the water in our largest tank, 0. 2317 L, from 20°C to 80°C – Using an Omega CIR-3016 (100 Watt) – Therefore, the longest time needed to heat the water is 9. 7 minutes

Water Heating Source Omega Immersion Cartridge Heater • 150 Watt Heater • Incoloy® Sheath - Efficient heat transfer - Sealed tip - Corrosion resistant. • Special Insulation - High dielectric strength - Faster heat-up time • Small size - 1/2 inch diameter

Water Temperature Sensor TD 4 A - Liquid Temperature Sensor • RTD (resistance temperature detector) sensors • Respond rapidly to temperature changes • Accurate to ± 0. 7 °C at 20 °C • Temp. range: -40 °C to 150 °C (-40 °F to 302 °F) • Supply Voltage/Current: 10 Vdc, 1 m. A typ. • Linear outputs.

Power Controllers Power-IO Solid State Relays • Surge protection • DC control input: 4 -32 VDC • Operating Voltage: 24 -330 V • Max Load Current: 25 A • Affordable price (under $40)

Software Design Flowchart I Start User input desired testing parameters (Temp/Humidity/Pressure/Duration) and the max pressure, max temperature should be allowed Test Temperature sensor Is temp sensor ok? Show error message! Terminate the program! N Y Set up testing environments N Start testing? Y All desired testing parameters are satisfied? Y Timer counts Record testing results N End test? Y End Show violation message! N Y Continue without adjustment? N

Software Design Flowchart II Set up testing environments Display Gas Temp (H 2 and O 2) Heat H 2 and O 2 water tank Heat PEM water tank Adjust pressure of H 2 and O 2 gas Display water temperature Display PEM temperature Display pressure of H 2 and O 2 gas line Exceed max water temp? Exceed max gas pressure? Display gas humidity (H 2 and O 2) N Exceed max Y water temp? N N Desired gas humidity? Y Y Shut Off! N Show warning! Dangerous level? Y Show warning! Dangerous level? N N Desired temp? Y Y Shut Off! End set up testing environments Y Dangerous level? N N Desired gas pressure? Y Y Shut Off! N

USB-1208 LS + Lab. VIEW™ drivers USB-based DAQ module ( $109. 00 x 2 + $ 49. 00) • 8 Single-Ended or 4 Differential Analog Inputs • 12 -bit (Diff. )/11 -bit (SE) Resolution • Two 10 -bit Analog Outputs • One 32 -bit External Event Counter • 16 Digital I/O Lines • External Trigger Input • Sample Rate 1. 2 KS/s

Design Process Original Project Objectives 1. Flow Systems 2. H 2 & O 2 Electrolysis and Delivery Major Project Scope Changes Flow System 3. Temperature Systems 4. Pressure Systems 5. Humidity Systems Electrolysis System H 2 & O 2 Tanks 6. Mechanical Assembly (Optional) Scope Change Impact Time Research Current Project Objectives 1. Mechanical Assembly 2. H 2 & O 2 Creation and Delivery Concept Generation Concept Selection Feasibility Analysis 3. Temperature Systems 4. Pressure Systems 5. Humidity Systems

Project Schedule

Budget

Questions