Metal Hydride for Hydrogen Storage

Rex Harris

HydrailJuly 3-4, 2012

A major challenge in the exploitation of hydrogen as a fuel is:

STORAGE

The main options are:

High Pressure GasLiquid Hydrogen

Solid State

Each of these options have advantages and disadvantages.

Let’s consider each in turn.

Hydrogen Storage- Compressed Gas

Under pressure• Advantage

• well established technology, particularly on a relatively small scale

• Disadvantages• low to moderate

compression (15% losses)

• delivers hydrogen at high pressure

• Safety? (Real and/or perceived?)

Motor Show 2002

Neel Sirosh (Quantum), WHEC15, Yokohama, June 2004

Hydrogen Storage- Liquid

Cryogenic storage• Liquid hydrogen

• 21.2 K• ambient pressure

• Advantages• good compression• low pressure

• Disadvantages• 30% energy losses• “boil-off” in days

filling port

inner vessel

liquefiedH2(-253 °C)

suspension

safety valve

outer vessel

shut-off valve

Cooling water heat exchangerelectrical heater

Reversing valvegaseous/liquid

liquid extractiongas extraction

filling lineLevel probe

Super-insulation

gaseous H2(+20 °C bis +80 °C) to engine

Automotive Design:

Liquid HydrogenDevelopment of Storage Technology

Condensation Temp = -252°C

Critical Temp = -241°C

Hydrogen Storage

- Solid-state

A. Zuettel, A. Borgschulte, Int. Symp. on H2 Energy, Richmond, USA, 12-15 Nov 2007

The main advantages: Potential of high hydrogen density at moderate temperatures and pressures.

Main disadvantages: weight and volume of the storage material.

The hunt is now on for a viable, light weight, solid state store for automotive

applications.

Fortunately there are transport applications where the weight of the storage material

can be an asset

These are:

Boats and Trains

In our work we have focussed on boats but I can also report on some recent

involvement in trains

In the School of Metallurgy and Materials we have research interests in NdFeBmagnets and in Intermetallic HydrogenStorage materials.

Consequently we have built a canal boat (The Ross Barlow) as an effective demonstrator of both technologies.

The Protium Project

In this vessel:

46 kwh stored in the lead-acid batteries (weight 1.2 tonne)

52 kwh stored in intermetallic hydrogen store (weight 0.5 tonne including system)

Valve

Filter and manifold

FuelcellGas

distribution

Hydride store designModular design incorporating 6 horizontal stainless steel tubes per module with a water cooling/ heating jacket

Mot

or

Ti0.93Zr0.05(Mn0.73V0.22Fe0.04)2

Hydrogen RechargingHydrogen charging vs. time

Procedure1) Connect exterior hydrogen

supply at 20Bar2) Manually open a number of

valves3) Follow computer controlled

filling procedure

0

1000

2000

3000

4000

5000

6000

0 1 2 3 4 5 6 7

Time (Hours)H

ydro

gen

Flow

ed (L

trs)

Static water With water cooling flow

0

10

20

30

40

50

60

70

0 1 2 3 4 5 6 7Time (Hours)

Wat

er te

mpe

ratu

re (C

elsi

us)

Static water With water cooling flow

Pressure composition isotherms

• where α- & β-phases co-exist, a plateau occurs

• plateau pressure is temperature dependent

InP= ∆H ∆SRT R

As received

After 10 cycles

Ti0.93Zr0.05(Mn0.73V0.22Fe0.04)2

A vital aspect of the storage material is its longevity.

Cycling performance

A very large scale marine application for metal hydride/

PEM/ PM motor.

A large scale marine application also using a PM motor, a PEM fuel cell and metal hydride store

HDW, Shipyard/ Germany

In this case storing around one tonne of

hydrogen in 50 tonnes of metal hydride

In the past week we have used one of the Ross Barlow Storage Units (0.5 Kg of H2) to provide

the H2 for a fuel cell demonstration train in the Rail

Centre.

Together with boats, could this herald a promising application for

metal hydride stores?

Thanks for listening

Acknowledgements:

Thanks are due to my colleagues Alex Bevan, David Book, Andreas Zuttel (EMPA),

Sal Adrwish and Dan Reed