PEM Fuel Cell Stack Sealing

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PEM Fuel Cell StackSealing

• Steve Koch
• Freudenberg-NOK General Partnership
• March 10, 2005

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The Freudenberg NOK Global PartnershipServing
Customers Worldwide
FREUDENBERG COMPANY
3.5 Billion
FREUDENBERG-NOK
1.0 Billion
NOK CORPORATION
3.0 Billion

• WORLDWIDE
• Global R D technology exchange
• Globally integrated supply of products from
  factories in 27 countries
• One-piece-flow lean manufacturing
• Zero Warranty focus
• Over 30,000 employees serving our customers
• Total automotive sales of approximately 4
  billion

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The Freudenberg NOK Global PartnershipServing
Customers Worldwide
FREUDENBERG COMPANY
3.5 Billion
FREUDENBERG-NOK
1.0 Billion
NOK CORPORATION
3.0 Billion

• Freudenberg NOK Group Companies Provide
• Fuel Cell Component Solutions Worldwide
• Sealing
• Gas Diffusion Materials
• Humidification Units
• Bipolar Plates
• Filtration
• Noise Isolation Mounting Systems

• WORLDWIDE
• Global R D technology exchange
• Globally integrated supply of products from
  factories in 27 countries
• One-piece-flow lean manufacturing
• Zero Warranty focus
• Over 30,000 employees serving our customers
• Total automotive sales of approximately 4
  billion

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Presentation Topics

• Fuel Cell Stack Sealing
• Stack Sealing Issues
• Addressing the Issues

• Low volume sealing solutions work well
• But, the solutions do not meet the cost target
• Design, Manufacturing and Quality Teams must
  work collectively to meet the volume cost
  targets

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Fuel Cell Stack Components
PEM Fuel Cell Stack
Bipolar Plate
The seal interfaces with all of the stack
components
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FC Seal Design Criteria

• Accommodate stack component tolerances
• Must be small (maximize active area)
• Low clamp load (minimize active area load
  fluctuations)
• Withstand chemical environment
• Design for assembly
• Seal placement / location is critical
• Easy to handle (packaging and delivery)
• High volume assembly
• Durability
• Automotive 5,000 hours
• Stationary 40,000 hours

• Seal design impacts the fuel cell function
• It should not be an after thought!

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Some of Todays Sealing Solutions

• Adhesive and/or bonding
• Die cut sheet stock rubber
• Molded rubber or o-ring
• Screen print rubber
• Carrier seal
• Seal integrated with GDL
• Seal integrated with bipolar plate
• Seal integrated with MEA
• Others ?

Multiple different materials

• Many Sealing solutions
• Many manufacturing methods
• Many different materials

Industry optimization required
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Todays US volume
Cells/stack 400 100
Seals/cell 2.5
Seals/stack 1000
250
Stacks 100
200
Seals 100,000 50,000
Seals volumes do not justify large investments
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A Current Stack Manufacturing Process
A complicated, costly, process
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Quality

• Apply six sigma capability
• 3 stacks per hundred will have a defective cell
  seal
• If one cell leaks, the entire stack may require a
  rebuild

• The seal quality requirements are high
• Low volume 100 inspection drives cost up

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Presentation Topics

• Fuel Cell Stack Sealing
• Stack Sealing Issues
• Addressing the Issues

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Issues with current sealing methods

• High Cost
• Designs have not been optimized
• Stack Assembly optimization
• Quality requirements are high
• Investment is needed to reduce costs, but
  todays volumes do not justify the investment
• Test methods being developed

High cost inhibits high volumes
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Presentation Topics

• Fuel Cell Stack Sealing
• Stack Sealing Issues
• Addressing the Issues

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Design Optimization

• Concurrent designing assures component
  compatibility and system optimization
• Optimized designs will lead to material
  optimization
• Robust designs assure that the components work
  under a variety of conditions
• Integrated seals will lead to stack assembly
  improvements

Design Optimization will lead to process
optimization
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Example of Optimized Seal

• Seal integrated with MEA
• Old process map
• New process map

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Example Seal integrated with MEA
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Current Stack Manufacturing Process
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Stack manufacturing process using a seal
integrated with MEA
Purchase
Integrated seal
on MEA
Align
Place Cooling Bi-
Purchase
Assemble First
polar plate with
Integrated seal
Bipolar Plate
Bipolar Plate
to plate
Integral Seal
Purchase
Cooling Plate
with Integral
Seal
Single Fuel Cell
Assembled
A simple, lower cost process
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Can We Create The Volumes?

• Market forces
• Niche markets
• Accepts initial higher costs
• Ensures the business is sustainable
• Niche markets can be slow to develop
• Subject to uncertainties
• Costs and/or volumes may take too long
• Government funding
• Governments must commit to purchasing fuel cells
• Governments must commit to continued RD and
  manufacturing funding

Innovative government funding can create small
volumes High volumes need to come from
investments that lower costs
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Addressing the Issues

• Lower costs
• Integrate components to reduce part counts
• Optimize the material utilization
• High quality requirements
• Robust designs
• Concurrent integrated system design
• Investment risk
• Government funding to help start demand
• Use Lean Systems to manage the investment risks

All the issues can be resolved
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Can History Guide Us?

• An example the introduction of automobiles
• In 1908, an automobile cost 3000
• By 1923, a model T cost 260 and was affordable
  by millions
• The introduction of a new manufacturing
  technology, the assembly line, reduced the costs

Today, fuel cells need a similar manufacturing
technology breakthrough