Broad Base. Best Solutions.
Graphite Materials and Systems
Specialty
Graphites for
Energy Storage
22
Specialty Graphite and Process
Solutions – made by SGL Group.
̥̥ Advanced material, equipment,
and process solutions
̥̥ Engineered for customers from
more than 35 industries
̥̥ Tailor-made from the most
comprehensive product portfolio
̥̥ In-depth production and
material knowledge
̥̥ Consistent high quality, performance,
and service
̥̥ Attractive total cost of ownership
Broad Base. Best Solutions.
Business Unit Graphite Materials and Systems
3
Advanced solutions
enable our customers
to get ahead.
SGL Group offers advanced solutions – even for challenging applications.
We understand the specific requirements of our customers and combine
in-depth production, material, and engineering knowledge with the most
comprehensive specialty graphite portfolio. This makes us the partner of
choice to leading companies in many different industries.
Exceptional resistance to heat and corrosion, high
SGL Group covers the entire value chain of
purity and mechanical strength are just a few of
specialty graphite production, including raw
the outstanding properties which our materials
material processing, semi-finished product
offer. Specialty graphite products from SGL Group
manufacture, precision machining, purification,
achieve optimal results where other materials fail.
and coating. When it comes to engineering of
No matter what your specific requirements might
equipment and process solutions our service
be, we will identify the best solution from the most
range makes the difference: We offer mechanical
comprehensive range of specialty graphites.
and process design, production, assembly, commissioning, and service – all from a one-stop shop.
̥̥ Fine grain graphite: isostatic, vibrationmolded, die-molded, extruded
This is how we control and ensure the consistent
̥̥ Expanded natural graphite
high quality, reliability, and performance of our
̥̥ Carbon fiber-reinforced carbon (C/C)
products – and enable our customers to become
̥̥ Soft and rigid graphite felts
more competitive. Challenge us. We are there for
̥̥ Silicon carbide-coated graphite materials
you worldwide.
Additionally we use other materials like PTFE,
Specialty graphite solutions for energy storage
silicon carbide, and specialty metals.
­­­
Energy storage systems are a key component in
With our portfolio and technical know-how
enabling the shift towards renewables making
spanning more than 35 different industries,
the energy revolution a success and ensuring
we engineer tailor-made solutions in close
the mobility of the future. With over 30 years of
partnership with our customers.
experience and an innovative product portfolio
SGL Group is the preferred partner of leading
r Production of expanded graphite foils
companies worldwide.
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Specialty graphites – made by SGL Group.
Energy storage solutions.
SIGRACELL® is the new brand name for our
specialty graphite for energy storage.
Lithium-ion batteries
Flow batteries
Typical applications Lithium-ion batteries (LiB) Vanadium redox flow batteries (VRFB)
Iron-chromium redox flow batteries (FeCrRFB)
SIGRACELL® battery felts
Products
SIGRACELL® specialty graphites
of the SGL GroupSIGRACELL® bipolar plates
Materials made of Graphite anode materials Electrodes
carbon and graphite Carbon composite anode materials Bipolar plates
Bipolar foils
SPECIALTY GRAPHITE solutions FOR ENERGY STORAGE
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Energy storage systems facilitate the efficient use of
Based on our long-term experience and close development
renewable energies and provide a fast and reliable solution
partnerships we provide tailor-made solutions to our
for off-grid energy supply. Thanks to the unique properties
customers.
specialty graphites play a vital role in this new applications.
With their high electrical conductivity, corrosion-resistance
and material purity our specialty graphites meet the
highest standards for quality, efficiency and environmental
compatibility. This leads to an increase of performance and
reliability of energy storage in a wide range of applications.
Advanced batteries
Fuel cells
High-temperature batteries (NaNiCl2/NaS)
Polymer-electrolyte fuel cells (PEM)
Advanced lead-acid batteries (ALAB) Phosporic-acid fuel cells (PAFC)
SIGRACELL® battery felts SIGRACET® carbon papers
SIGRACELL® expanded graphite powders SIGRACELL® bipolar plates
SIGRACELL® graphite foils
Electrodes
Gas diffusion layers (GDL)
Conductive additives Bipolar plates
Active Masses
More information can be found at
www.sigracet.com
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Graphite powder for
lithium-ion batteries
Our cutting-edge battery lab creates tailormade material solutions for our customers
and development partners.
It enables us to develop and characterize
new materials using particle engineering
and working according to industry
standards.
SPECIALTY GRAPHITEs FOR LITHIUM-ION BATTERIES
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Specialty graphites for
lithium-ion batteries
Our graphite anode materials are used in lithiumion batteries for mobile consumer appliances,
electric vehicles and stationary energy storages for
photovoltaic and wind. In order to spur technological progress even further, we invest in new
generations of graphite-based anode materials and
take active part in national and international
networks.
For over 15 years we have been working in close
cooperation with Hitachi Chemical Corporation,
supplying our partner with anode material for
lithium-ion batteries in consumer electronics, as
well as for automotive and industrial applications.
SGL Group is one of the largest manufacturers
of LiB anode materials and plays a major role
c LiB test cell production in a clean room atmosphere
in the advancement of LiB technology like C/Si
compounds.
As a member of the Lithium-Ion Battery
Competence Network (KLiB) we seek to strengthen
Germany's competitiveness in this key technology.
That’s why we are continuously working together
with industrial enterprises and research institutions
to improve battery cell performance, service life and
safety.
Further we invest in new generations of carbon
and graphite-based battery materials for the next
generation coordinated by our Energy lab and
Application Center.
c Electrode production at the Technology & Innovation Center
for subsequent electrochemical characterization
b Anode material
for lithium-ion batteries
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Specialty graphites for flow batteries
Reliable and easily adaptable to meet the specific requirements.
Flow batteries enable energy storage on a scale of
kWh to MWh and provide the perfect solution for
3
2
1
2
3
5
5
4
4
stationary applications. They are well-suited as
temporary storage for grid stabilization, industrial
back-up power, integration of renewables such as
wind and photovoltaic as well as off-grid power
supply for mobile radio transmitters and remote
households. The main advantage of flow batteries is
that they separate output (MW) and energy (MWh).
The two can be adjusted independently of one
another and are easily adaptable to the specific
requirements at hand.
SGL Group ranks among the leading
manufacturers of specialty graphites and
Charge / Discharge
graphite components for redox flow batteries.
We have applied our long-term experience and
c Schematic diagram
close cooperation with customers to develop special
of redox flow battery
1Membrane
2 Permeable electrode
3 Bipolar plate
4 Storage electrode
5Electrolyte
materials and products for energy storage:
SIGRACELL battery felts, bipolar foils and plates.
Continuous improvement of our materials has
significantly enhanced the performance and service
life of our customers flow batteries.
Specialty graphites for flow batteries
Applications
Permeable electrodes
Bipolar plates
SIGRACELL battery felts
SIGRACELL bipolar foils and plates
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SPECIALTY GRAPHITEs FOR FLOW BATTERIES
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Low cell resistivity and high electrolyte permeability are crucial factors for flow battery electrodes.
Accordingly, the contact resistivity of the bipolar
plate and felt electrode, as well as the permeability
of the felt electrode largely depend on surface
pressure and felt compression, and can be
controlled by the compression rate:
• As the compression rate increases, resistivity
decreases, as does permeability.
• Conversely, permeability and resistance increase
as the compression rate decreases.
Inhomogeneity in the battery felt can lead to impermeable areas reducing the overall performance of
the system. Therefore SGL Group is continuously
working on tighter tolerances for area weight and
thickness of our battery felts. This enables our
customers to optimize the compression rates to
ensure the best battery performance possible.
2
Additional technical information please
find in our White Paper: “SIGRACELL Carbon
c Flow battery components
Components for Flow Batteries” on request.
Relative electrical resistivity of graphite felt
Electrolyte permeability of graphite felt electrodes
100
Electrolyte permeability [darcy]
Electrical resistivity [%]
80
60
40
20
0
0
5
Compression rate [%]
10
15
3
1 Ion-exchange membrane
2 SIGRACELL battery felt
3 SIGRACELL bipolar plate
20
25
160
1.6E-10
140
1.4E-10
120
1.2E-10
100
1.0E-10
80
8.0E-11
60
6.0E-11
40
4.0E-11
20
2.0E-11
0.0E-11
0
0
5
10
15
Compression rate [%]
20
25
30
35
Electrolyte permeability [m2]
1
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Partner for environmentally
friendly energy storage
We have used our extensive understanding
of specific customer requirements to refine
our portfolio of carbon and graphite felts.
The result: SIGRACELL battery felts for
energy storage. In Gildemeister Energy
Solutions’ flow battery system, they
contribute to the rapid supply of clean and
emission-free energy. They also increase
safety and storage ability.
This is just one example of an applicationspecific optimized solution from the
SGL Group.
SPECIALTY GRAPHITEs FOR ADVANCED BATTERIES
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Specialty graphites for advanced batteries
High-performance, versatile, efficient.
Battery production has become unthinkable without specialty
SGL Group’s combination of application-oriented research,
graphites. This is because of the unique material properties
extensive knowledge of materials and expertise in process
they offer:
technology make it the partner of choice in carbon components for energy storage.
• Good electrical conductivity
• Exceptional resistance to highly corrosive media
All material development work starts with a well-founded
• Low redox potential
understanding of the physical and chemical principles which
determine the material’s subsequent use. SGL Group has
Specialty graphites play an important part in advanced
its own energy laboratory with experienced specialists at its
batteries of all kinds. These include high-temperature batteries
main technology and innovation research center, and works
such as sodium-sulfur and sodium-nickel-chloride batteries, as
in close cooperation with leading universities and institutes.
well as advanced lead-acid batteries. In this context, specialty
This allows us to incorporate new findings in the field of
graphites are used as permeable electrodes, active masses or
electrochemical energy storage directly into our material
conductive additive.
development.
The key to the top product quality we provide for battery
applications is experience in selecting suitable raw materials.
Our broad material base, long-term partnerships with suppliers
and constant quality control measures ensure high-grade
battery materials in tight tolerances. The continuous
optimization of our processes puts us in a position to steadily
improve quality and performance. Based on this approach
SGL Group has launched the world’s most advanced felt
production line in 2011 at our production site in Meitingen,
Germany.
b Redox flow battery test cell
in our in-house Energy lab
Specialty graphites for advanced batteries
Applications
Permeable electrodes
Conductive additives
Active masses
SIGRACELL battery felts
SIGRACELL expanded graphites
SIGRACELL graphite foils
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SIGRACELL® battery felts
Permeable electrodes made of SIGRACELL
carbon and graphite felts are the first choice for
high-temperature batteries such as nickel-chloride
and flow batteries. Our battery felts are used for
anodes as well as cathodes. They facilitate an
efficient charge exchange between the electrolyte
and bipolar plate during battery charging and
discharging. This is thanks to a unique combination
of electrical conductivity, electrochemical stability,
high porosity and good elasticity.
The sizes we provide are even enough to cover
the needs of large-scale redox flow systems.
We supply battery felts in standard sizes up to
1270 mm (50") in width in 30 m (98") rolls.
Beyond that, we produce carbon and graphite
felts in customer-specific dimensions.
c SIGRACELL carbon and graphite felts
Advantage of our complete inhouse value chain
fiber
raw felt
carbonizing
carbon felt
graphitizing
graphite felt
cut-to-size
Material data for our SIGRACELL® battery felts
Carbon and graphite felts
Units
GFA6 EA
KFD2.5 EA
GFD4.6 EA
GFD3 EA
Rayon
Polymer
Polymer
Polymer
g/cm³
0.08
0.1
0.09
0.09
mm (in)
6 (0.24)
2.5 (0.10)
4.6 (0.18)
3 (0.12)
Fiber type (precursor)
Bulk density
Nominal thickness
Area weight
g/m²
500
250
425
300
Electrical resistivity _|
Ωmm
< 12
< 30
<6
<6
Electrical resistivity ||
Ωmm
<4
< 10
<3
<3
%
< 0.3
< 0.6
< 0.2
< 0.2
Ash value (580 °C)
SPECIALTY GRAPHITEs FOR ENERGY STORAGE
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SIGRACELL® bipolar foils
and end-plates
c SIGRACELL bipolar foils made of expanded graphite
c SIGRACELL bipolar end-plates made of graphite composite material
Available sizes of our SIGRACELL® bipolar foils
and end-plates
The main features that distinguish expanded natural graphite are
exceptional resistance to chemicals and good electrical conductivity.
Together with high-grade fluoropolymers, our thin, high-density
Grade
SIGRACELL bipolar plates can be used for a broad spectrum of
Thickness
mm (in)
Length
mm (in)
Width
mm (in)
applications. Thanks to their great resistance to corrosion, our
TF6
0.6 (0.02)
900 (36)
600 (24)
SIGRACELL products are ideally suited for the demanding cell
PV10
0.6 (0.02)
900 (36)
600 (24)
chemistry in battery systems. Advanced lead-acid batteries are
FR10
0.6 (0.02)
900 (36)
600 (24)
but one example of the many uses for SIGRACELL foils.
F100
2-4 (0.12-0.16)
1180 (47)
870 (34)
We will also be glad to produce other formats upon.
Material data for our SIGRACELL® bipolar foils and end-plates
Expanded graphite
Units
Polymer type
Polymer content
Bulk density
Tensile strength
Electrical resistivity
Thermal conductivity _|
TF6
PV10
FR10
F100
Fluoropolymer
Fluoropolymer
Fluoropolymer
Thermoset resin
%
6
10
10
20
g/cm³
1.75
1.65
1.85
2.05
MPa
20
25
40
28
Ωµm
< 10
< 10
< 10
< 270
Wm⁻¹K⁻¹
6
6
5
> 20
Thermal conductivity ||
Wm⁻¹K⁻¹
300
300
400
> 20
Permeability (helium)
mg/(m2s)
< 1 x 10⁻³
< 1 x 10⁻³
< 5 x 10⁻³
< 1 x 10-3
ppm
< 150
< 150
< 150
< 500
Impurities (metals/ transition metals)
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We will find the best solution –
in partnership with you.
The fascinating potential of carbon as a
material excites us and inspires us to develop
optimum solutions in partnership with
our customers.
With our comprehensive material portfolio
and valuable specialist know-how, we can
manufacture tailored products – even for
the most challenging applications.
Consistently high quality, a global presence,
innovative strength, and the extensive
experience of our employees make us a
reliable partner to our customers.
Whatever challenges you face, together we
will find the best solution.
SGL Group – the Carbon Company
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SGL Group –
The Carbon Company.
A leading global
manufacturer of
carbon-based products.
Q Unique product portfolio
Q Innovative technologies and solutions
Q Production sites close to sales markets
Q Technology & Innovation Center in Germany
with international networks
b Serial production
of SIGRACELL battery felts
We have wide-ranging expertise in raw materials,
We use this broad base to offer our customers the
advanced manufacturing processes, and long-
best solutions possible. That’s how we live up to our
standing application and engineering know-how.
claim: Broad Base. Best Solutions. This claim is also
We have a comprehensive portfolio of carbon,
upheld by our corporate SGL Excellence philosophy
graphite, and carbon fiber products and our
of continuous improvement.
carbon fiber to composites. With a global sales and
­
distribution network and modern production sites
More information can be found by visiting:
in Europe, North America, and Asia, we are close to
www.sglgroup.com
integrated value chain covers everything from
our customers throughout the world.
C sglgroup
sglgroup
Contact
europe/MIDDLE EAST/AFRICA
SGL CARBON GmbH
Drachenburgstrasse 1
53170 Bonn/Germany
gms-europe@sglgroup.com
americaS
SGL TECHNIC Inc.
Polycarbon Division
28176 No. Avenue Stanford
CA 91355 Valencia/USA
gms-americas@sglgroup.com
asia/pacific
SGL CARBON Far East Ltd.
12 Fl, Shanghai Oriental Plaza
31 Wujiang Road
Shanghai 200041/PR China
gms-asia@sglgroup.com
® registered trademarks of SGL CARBON SE
02 2016/0.5 3NÄ Printed in Germany
This information is based on our present state of knowledge and is intended to provide general notes on our
products and their uses. It should therefore not be construed as guaranteeing specific properties of the products described or their suitability for a particular application. Any existing industrial property rights must be
observed. The quality of our products is guaranteed under our “General Conditions of Sale”.
Graphite Materials & Systems
SGL CARBON GmbH
Soehnleinstrasse 8 | 65201 Wiesbaden/Germany
www.sglgroup.com/gms