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Novel Phosphazene Compounds for Enhancing Stability and Safety of

Lithium-ion Batteries

Kevin L. Gering, PhD Principal Investigator, Applied Battery Research Energy Storage & Transportation Systems Michael T. Benson, PhD, Interfacial Chemistry Mason K. Harrup, PhD, Chemical Synthesis Harry W. Rollins, PhD, Interfacial Chemistry Sergiy V. Sazhin, PhD, Applied Battery Research Fred F. Stewart, PhD, Polymer Chemistry

May 17, 2012 Project ID ES027 2012 DOE Vehicle Technologies Program Annual Merit Review This presentation does not contain any proprietary, confidential, or otherwise restricted information.

Timeline

Project Start: Jan. 2009 Project End: Ongoing Percent Complete: TBD, depends on progression of new milestones.

Barriers

Cell/battery Life Abuse Tolerance, Reliability and Ruggedness Performance (energy density) Cost

Budget

Funding Received: FY 11: $ 400K FY 12: $ 500K

Partners

Argonne National Lab (ANL) Dow Chemical Princess Energy Systems Sandia National Lab (SNL) Lead: INL

Overview

Relevance Safety, life and cost of Li-ion batteries continues to be an issue for future vehicular and other high-demand applications. This is complicated by the drive toward higher energy systems (5V+ Cells).

Our objectives include: ♦ Synthesize novel solvents for Li-ion cells that are safer alternatives to volatile organics. Targets: prolonged operation at 5V+ and 60°C

, 3C rate, 300 mAh/g.

♦ Target alternative electrode materials that would further integrate stable performance and be chemically compatible with novel solvents. ♦ Determine what phosphazene structures are more tolerant to high and low voltage, and to high temperatures. ♦ Gain understanding of molecular-scale interactions between phosphazenes and other electrolyte components. ♦ Determine the effect of phosphazenes on SEI films and cell aging in general, using ABR-relevant electrode couples.

Our vision is to leapfrog lithium-ion technology to achieve a highly tunable inorganic battery chemistry with extremely high safety, stability, and longevity.

Milestones

Milestone Status Date Cell testing using LNMO/LTO and NMC/Carbon* couples: aging studies Completed October 2011

Phase 1 concept validation for alternative anode materials Completed October 2011

Cell testing using HE5050/Carbon couple: characterization of capacity and impedance attributes Completed December 2011

Cell testing using HE5050/Carbon couple: aging studies Completed March 2012

DFT study on complete FM Series (fluorinated cyclics) Completed February 2012

Synthesis of newer FM series Completed August 2011

Phase 2 concept validation for alternative anode materials Completed March 2012

Initial PALS measurements of alternative anode materials Completed March 2012

Synthesis of newer Ionic Liquid Phosphazenes In Progress

Abuse testing of INL Phosphazene electrolyte additives (SNL) In Progress

Collaboration with ANL regarding scale-up of INL electrolyte compounds In Progress

Various supporting characterization and cell testing will be ongoing throughout FY 2012.

Approach

The INL has foremost experts in phosphazene chemistry (Stewart, Harrup, and Klaehn) that are producing new classes of novel compounds for use in Li-ion batteries. They maintain historical knowledge of phosphazene chemistry and related applications.

This work is split under (1) synthesis (solvents, electrodes), (2) characterization, (3) DFT modeling, and (4) lithium-ion cell testing. Upfront issues are

♦ Voltage and thermal stability ♦ Lithium salt solubility ♦ Transport properties ♦ Effective energy density ♦ Overall chemical compatibility in cell and related aging ♦ Molecular interactions (solvent-ion) and SEI

Coin cell testing covers issues of formation, interfacial impedance, polarization testing, and aging. We investigate the performance of our electrolytes against relevant ABR electrode couples as they become available.

Note: Best Candidate electrolytes have been sent to SNL for abuse-tolerance testing.

Alternative Electrolyte Materials Phosphazenes

SM7

Protons removed for clarity.Red = oxygen, Blue = nitrogenOrange = phosphorus, Grey = carbonPurple = lithiumSM7

Protons removed for clarity.Red = oxygen, Blue = nitrogenOrange = phosphorus, Grey = carbonPurple = lithium

FM3FM3

PhIL-2

Benefits: Inherently stable and non-flammable

Very low vapor pressure Choice of R groups (pendant arms) has a profound influence on properties

Good lithium salt dissolution

Challenges:

High viscosity Need to attenuate N-Li+ attraction that occurs due to electron doublet transfer

SMSM: employs ether groups attached to the phosphorus centers

ALAL: employs unsaturated analogues of the SM series

FMFM: employs fluorinated analogues of the SM series

PhIL: ionic liquid variation

SMSM: employs ether groups attached to the phosphorus centers

ALAL: employs unsaturated analogues of the SM series

FMFM: employs fluorinated analogues of the SM series

PhIL: ionic liquid variation

Selected Series of INL Phosphazene Compounds

Approach

All materials covered by patents issued or pending.

Novel Approach to Anode Engineering • Classes of phosphazene compounds are being tested as new intercalative host materials for lithium-ion battery anodes. These compounds and their formulations provide the following benefits:

Synthesis of novel 3D polyphosphazene scaffolds, which can support addition of custom functional groups and dynamic materials (nano-Si).

Addition and formulation of materials to enhance electronic conductivity, energy storage capacity, and other physical properties,

Highly engineerable to achieve particular properties (e.g., competitive energy storage capacity could be achieved).

Inherently low flammability due to presence of phosphorous.

Economical method to apply phosphazene electrode material to metal current collectors.

Successful cell testing to 5V!

PN

PN

P

N

O O

OO

OO

(3)

OH

OH

OHHO

HO

HO

PN

PN

P

N

O O

OO

OO

(4)

OH

OH

OHHO

HO

HO

Examples of base phosphazene structures: tbuHQCP or TBHQ (left) and HQCP (right).

Approach

Technical Accomplishments & Progress • New phosphazene compounds have been synthesized as part of our suite of materials

aimed at voltage and temperature tolerant electrolyte additives (FM, PhIL).

• Cell testing has continued with ABR-relevant electrode couples (recently HE5050/Carbon). Test results are encouraging regarding capacity retention and aging trends, with INL additives exceeding performance of the baseline in some cases.

• Recent voltammetry measurements confirm INL additives provide expanded voltage stability. Our improved voltammetry technique yields more precise determination of SEI parameters.

• Initial abuse testing at SNL shows that INL electrolyte additives enhance thermal stability.

• Density Functional Theory (DFT) simulations have been performed to determine the solvent-to-lithium binding energies for key phosphazene additives (full FM series). Reducing this interaction will promote greater cell efficiency in terms of interfacial processes.

• Alternative anode materials based on phosphazene chemistry have been synthesized and tested to 5V, indicating these are viable hosts for lithium-ion cells. Three classes of materials have been tested, showing an evolution of improved performance.

• Initial Positron Annihilation Spectroscopy (PAS) measurements have been completed for first-generation INL alternative anodes.

Testing Additives with ABR-relevant Electrodes

Cycle Number0 5 10 15 20 25 30 35 40

Cap

acity

, mA

h

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

C/10

C/3 C/1 C/103C

HE5050/Carbon, Discharge Capacities2032-type coin cells

Baseline ElectrolyteSM-4, 3%SM-6, 3%FM-2, 3%PhIL-2, 3%

3-cell groups shown for each test condition.

Performance ranking: SM-6 > FM-2 > PhIL-2 > SM-4

Improvement over baseline performance is seen in SM-6 and FM-2 in some cases.

Tech. Accomplishments

SNL Abuse Testing of INL Additives (3%)

0

50

100

150

200

250

300

350

400

0 100 200 300 400 500

Temperature (C)

Heat

ing

Rate

(C/m

in)

BASELINE (2:8)_44SM6_14FM2_15PhIL-2_17

0

10

20

30

40

50

60

70

80

90

100

225 230 235 240 245 250

Temperature (C)

Heat

ing

Rate

(C/m

in)

BASELINE (2:8)_44SM6_14FM2_15PhIL-2_17

0

200

400

600

800

1000

1200

1400

1600

1800

2000

0 100 200 300 400 500

Temperature (C)

Gas V

olum

e ST

P (m

L)

BASELINE(2:8)_44_volSM6_14_vol

FM2_15_vol

PhIL_2_17_vol

INL additives were tested within 18650 cells having NCA/Carbon. Additive levels were 3% in a baseline of 1.2M LiPF6 in EC-EMC (2:8).

• All additives reduced the peak heating rate by as much as 100 °C/min, compared to BL.

• Some additives delayed the onset temperature a small amount.

• All additives dramatically changed the progression of gas evolution, compared to BL.

Shown Results are for initial testing, with more in progress.

Tech. Accomplishments

DFT Modeling of Li-Solvent Binding Energy # CF3 Groups vs BE

# CF3 Groups

0 1 2 3 4 5 6

BE (k

cal/m

ol)

56

58

60

62

64

66

68

70

72

74

76

R = 0.998

N

PN

P

NP

O

O

O

O

O

O

N

PN

P

NP

O

O

O

O

O

O

CF3

1 2

3b

N

PN

P

NP

O

O

O

O

O

O

CF3

CF3

4b

N

PN

P

NP

O

O

O

O

O

O

CF3

CF3

F3C

5

N

PN

P

NP

O

O

O

O

O

O

CF3F3C

CF3

CF3F3C

F3C

Modeling was done using Gaussian03, B3LYP/6-311++G(d,p). Structures are true minima (no imaginary frequencies).

BE is seen to decrease linearly, likely due to increasing electron withdrawing effect as more CF3 groups are added. This also leads to molecular distortion and slightly weakened coordination to Li+.

Lower BE translates to lesser solvation of Li+ and more efficient charge transfer.

A sampling of structures that were modeled….

Tech. Accomplishments

Voltammetry of Phosphazene-based Electrolytes

Example measurements (FM series)

• Phosphazenes do increase electrochemical window at negative and positive ends.

• All the windows are less than operating voltage of Li-ion cells.

• At potentials beyond the electrochemical window, passivation does occur forming SEIs.

• Properties of passivating layers need to be measured quantitatively.

Electrolytes: baseline (1.2M LiPF6 EC:MEC (2:8)) and the blends of 20% of each phosphazene with 80% baseline.

-160

-140

-120

-100

-80

-60

-40

-20

0

20

40

0 1 2 3 4 5 6

Cur

rent

den

sity

/ µA

cm

-2

Potential vs. Li/Li+ / V

FM4

FM2

Control

Ni

Al

Electrochemical window at 1µA/cm2 Control 0.649V FM2 1.711V FM4 1.983V

EW

Unchanged control wave

Tech. Accomplishments

Cell Testing, Alternative Anodes

Cell Testing was performed to determine cycling performance over voltage.

Stage 1: C/10 cycling to progressively higher voltage (max. 5V) with no taper charging.

Stage 2: C/10 cycling to progressively higher voltage (max. 5V) with 2.5 hr taper charging.

Cell Particulars: Case: coin cell (2032-type) Anode: INL Phosphazene Matrix on Cu Cathode: Li-NiMnCo Oxide (3M) on Al Electrolyte: 1.2M LiPF6 in EC-EMC (2:8) Phase 1 and 2 studies are complete, covering a matrix involving three classes of polymeric materials.

Initial test results confirm that INL anode materials are feasible in lithium-ion batteries, and that they perform better at higher voltages to support higher-power capability. Optimization of cyclomatrix, electrode formulation, charging protocol, and electrolyte will improve capacity, cycling rate, and longevity.

Anode laminate thickness: 70-90 μm in most cases, and are non-calandared.

100 micron 10 micron100 micron 10 micron

Tech. Accomplishments

Phase 1 Study: C/10 discharge cycling with no taper charges.

g p

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

0 2 4 6 8 10 12Cycle Number

Capa

city

(mAh

r)

1803-30-5 (Enriched)

1803-30-5 (Enriched)

1803-30-5 (Enriched)

1803-30-5

1803-30-5

1803-30-5

1803-30-8 (Enriched)

1803-30-8 (Enriched)

1803-30-8 (Enriched)

1803-30-8

1803-30-8

1803-30-8

1803-30-11 (Enriched)

1803-30-11 (Enriched)

1803-30-11 (Enriched)

1803-30-11

1803-30-11

1803-30-11

1803-30-12 (Enriched)

1803-30-12 (Enriched)

1803-30-12 (Enriched)

1803-30-12

1803-30-12

1803-30-12

These tests are the first of their type for these new materials. Cycling up to 5V is confirmed. Performance could improve by optimizing polymerization, formulation, and charge protocol.

Formation Period

Increasing Voltage 0.1V per cycle

5.0V

4.4V

Tech. Accomplishments

Discharge Capacity of Different Electrode Formulations for a Range of Voltage Spans

0

0.2

0.4

0.6

0.8

1

1.2

1.4

0 1 2 3 4 5 6Cycle Number

Capa

city

(mAh

r)

1803-30-5 (Enriched)

1803-30-5 (Enriched)

1803-30-5 (Enriched)

1803-30-5

1803-30-5

1803-30-5

1803-30-8 (Enriched)

1803-30-8 (Enriched)

1803-30-8 (Enriched)

1803-30-8

1803-30-8

1803-30-8

1803-30-11 (Enriched)

1803-30-11 (Enriched)

1803-30-11 (Enriched)

1803-30-11

1803-30-11

1803-30-11

1803-30-12 (Enriched)

1803-30-12 (Enriched)

1803-30-12 (Enriched)

1803-30-12

1803-30-12

1803-30-12

Stage 2 C/10 cycling with taper charges.

30-11 improves over entire voltage range! Optimal Vmax is 4.8-4.9V for most systems; INL Electrolyte additives would increase this.

4.6V 4.9V 5.0V 4.7V

Phase 1 Study Tech. Accomplishments

0

0.2

0.4

0.6

0.8

1

1.2

1.4

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Capa

city

(mAh

r)

1803-30-6 Enriched

1803-30-6 Enriched

1803-30-6 Enriched

1803-30-6

1803-30-6

1803-30-6

1803-30-7 Enriched

1803-30-7 Enriched

1803-30-7

1803-30-7

1803-30-7

1803-30-9 Enriched

1803-30-9 Enriched

1803-30-9 Enriched

1803-30-9

1803-30-10 Enriched

1803-30-10 Enriched

1803-30-10 Enriched

1803-30-10

1803-30-10

1803-30-10

1803-30-13 Enriched

1803-30-13 Enriched

1803-30-13 Enriched

1803-30-13

1803-30-13

1803-30-13

1803-30-13c Enriched

1803-30-13c Enriched

1803-30-13c

1803-30-13c

1803-30-13c

1803-30-14 Enriched

1803-30-14 Enriched

1803-30-14 Enriched

1803-30-14

1803-30-14

1803-30-14

1803-30-16 Enriched

1803-30-16 Enriched

1803-30-16 Enriched

1803-30-16

1803-30-16

1803-30-16Cycle Number

C/25

Higher capacity is attained at lower voltages, compared to Phase 1 materials. Distinct differences in polymeric chemistry result in differences in energy storage. We can utilize such correlations to engineer finely tuned materials.

Formation Period

Increasing Voltage 0.1V per cycle

5.0V

Phase 2 Study: C/10 discharge cycling with no taper charges.

4.4V

Tech. Accomplishments

Selected

dQ/dV to 4.7V

Differential Capacity

-3

-2

-1

0

1

2

3

4

5

2.5 3 3.5 4 4.5 5

Voltage

Q'

10/10/80, enr.

20/0/80, not enr.

10/10/80, not enr.

20/0/80, enr.HQCP-based Polymer

Si Peaks

Charging →

← Discharging

Differential Capacity

-3

-2

-1

0

1

2

3

4

5

2.5 3 3.5 4 4.5 5

Voltage

Q'

10/10/80, enr.

20/0/80, not enr.

10/10/80, not enr.

20/0/80, enr.HQCP-based Polymer

Si Peaks

Charging →

← Discharging

Differential Capacity

-3

-2

-1

0

1

2

3

4

5

6

7

2.5 3 3.5 4 4.5 5

Voltage

Q'

10/10/80, enr.

20/0/80, not enr.

10/10/80, not enr.20/0/80, enr.

TBHQ-based Polymer

Differential Capacity

-3

-2

-1

0

1

2

3

4

5

6

7

2.5 3 3.5 4 4.5 5

Voltage

Q'

10/10/80, enr.

20/0/80, not enr.

10/10/80, not enr.20/0/80, enr.

TBHQ-based Polymer

Tech. Accomplishments

PAS & PALS for Electrode Material Characterization Positron Annihilation Spectroscopy Positron Annihilation Lifetime Spectroscopy

2.5 2.55 2.6 2.65 2.7

1.22

1.24

1.26

0.57880.57890.5790.57910.57920.57930.57940.57950.57960.57970.57980.57990.580.58010.58020.58030.58040.58050.58060.5807

Sample 1: S parameter response 0.5799 +/- 0.0006

2.35 2.4 2.45 2.5 2.55

1.1

1.12

0.5808

0.5809

0.581

0.5811

0.5812

0.5813

0.5814

0.5815

0.5816

0.5817

0.5818

0.5819

0.582

0.5821

0.5822

0.5823

0.5824

Sample 2: S parameter response 0.5814 +/- 0.0005

PAS and PALS are critically important tools for characterizing structural details of solids down to the nano-level. Through these tools we can look at defect attributes (dislocations), micro-porosity, and particle fracturing over aging.

PAS measurements of INL phosphazene-based electrodes show consistent surface homogeneity, while detecting differences in electronic structure of the materials.

Tech. Accomplishments

Collaborations • Princess Energy Systems. Involved in formative discussions of incorporating

phosphazenes into Li-ion cells and corresponding intellectual property and market issues. Contact: Thomas Cripe

• SNL. Provided NMC/Carbon electrode material for INL coin cell studies. SNL is performing abuse tolerance testing on electrolytes having the best candidate INL additives to date. Contact: Chris Orendorff

• ANL. Provides ABR electrode materials for INL coin cell studies. Supports review of historical data from ANL testing of other electrolyte additives. This is ongoing. Contacts: Khalil Amine, Daniel Abraham

• Dow Chemical. Considering involvement in commercial production of INL electrolyte additives for Li-ion systems. Periodic discussions have been held, and a Non-disclosure Agreement (NDA) has been signed between INL and Dow. Contact: Dee Strand

• US SOCOM. Collaboration between USSOCOM, INL, and ANL will focus on producing a safer and more reliable lithium-ion battery chemistry for selected Navy platforms.

Future Work Continued synthesis work guided by DFT to fine tune solvent properties toward cell stability

and lowered association with lithium.

Parallel research at INL is targeting other phosphazene families and alternate salts to enable electrolyte systems having mostly phosphazene solvents that exploit the inherent low flammability of these additives.

7Li NMR: look at mechanism for thermal stability induced by phosphazenes.

Continued testing of INL electrolyte additives with ABR-relevant electrode couples. Half-cell studies on SEI films will be considered.

Continued testing at SNL for abuse tolerance, with an eye on how INL additives mitigate the onset of thermal runaway.

Alternative electrode materials: improvement and extension of performance (Phase 3): optimizing the cyclomatrix constituents (blends, and new scaffolds), enhancing conductivity, matching polymeric properties to other host materials (Si, carbon, etc.), usage of INL phosphazene electrolyte additives, and through understanding rate limitations. Economical synthesis and simple electrode manufacturing are advantages toward full-scale production.

High-voltage testing of INL electrolyte systems with INL alternative electrodes, using aluminum-clad coin cell hardware. Progress toward an “inorganic battery”.

Expanded characterization of electrode materials to include ellipsometry, PAS, PALS, solid-state NMR, and post-mortem analysis of coin cell internals.

Summary • INL phosphazene materials aimed at battery electrolytes has grown to include more fluorinated and

ionic liquid compounds to accomplish customized properties regarding lithium association.

• At additive levels (3%) INL phosphazene additives provide Thermal Stability within both the electrolyte and cell environment (e.g., SNL abuse test data). This behavior is advantageous toward prolonged battery life and to enable greater operation at elevated temperatures.

• Cell testing with HE5050/Carbon: In some cases INL additives perform better than BL electrolyte.

• Per voltammetry, INL phosphazenes improve properties of the SEI on cathode (+) side and increase operating voltage. Our method provides clear metrics by which to quantify SEI properties that are relevant toward issues of irreversible capacity loss, power, self-discharging, and shelf-life.

• Density Functional Theory (DFT) simulations confirmed lowered Binding Energy trends for successively higher fluorination of cyclic compounds.

• An underlying driver for this work is that replacement of carbon anodes would further improve safety of lithium-ion cells, particularly in cases of thermal runaway. We continue to build in the theme of a carbon-reduced “inorganic” battery chemistry to achieve longevity and safety under broader use conditions.

• INL Phosphazene-based intercalative host materials have undergone successful initial characterization and testing as anodes in lithium-ion cells. These materials offer a safer alternative to graphitic-based anodes, and are relatively inexpensive to produce.

• These materials function reversibly as lithium hosts, and allow operation at higher voltages (≥ 5V). They accommodate other host materials (Si, graphite) by acting as an elastic polymeric binder. Electrochemical cycling efficiency increases with voltage. PALS will give insights on microstructure.

Acknowledgements

• DOE Vehicle Technologies Program (VTP)

• Peter Faguy, DOE-EERE, VTP

• David Howell, DOE-EERE, VTP

• Tim Murphy, INL

• Chris Orendorff, SNL

This work would not be possible without the outstanding support from

• David Jamison, INL

• Christopher Michelbacher, INL

This work was performed for the United States Department of Energy under contract DE-AC07-05ID14517.

Technical Back-Up Slides

Decision Tree, Electrolytes Approach

Blend with Baseline Electrolyte to achieve 0, 1, 3, 5, 10% phosphazene by vol.

Repeat viscosity and conductivity for blends at RT

Primary Solvents (> 40% by vol)

Co-Solvents (10 - 40% by vol)

Additives (< 10% by vol)

Starting here with pure phosphazene compounds:

Lithium Salt Solubility

(LiPF6 or other viable salt) > 0.6 M

No Lithium Salt Solubility (LiPF6 or other viable salt)

0.2 - 0.6 M

No Lithium Salt Solubility (LiPF6 or other viable salt)

< 0.2 M Considering only pure phosphazenes

without salt

Yes Pure Solvent Viscosity No

< 5 cP

Yes Pure Solvent Viscosity

5 - 40 cP

Yes No Pure Solvent Viscosity

> 40 cP

Yes Yes Yes

Salted Conductivity No

(salt conc. ≤ 1 M) > 4 mS/cm

Salted Conductivity (salt conc. ≤ 1 M)

0.2 - 4 mS/cm

No Salted Conductivity (salt conc. ≤ 1 M)

< 0.2 mS/cm

Yes

Blend with Baseline Electrolyte to achieve 40, 60, 80, 100% phosphazene by vol.

Yes Blend with Baseline Electrolyte to achieve 0, 10, 20, 30, 40% phosphazene by vol.

Yes

Repeat viscosity and

conductivity for blends at RT Repeat viscosity and

conductivity for blends at RT

Thermal Stability Testing Cell Testing (SEI formation; capacity retention)

FURTHER CHARACTERIZATION & TESTING

Flashpoint Vapor Pressure CV/Voltammetry DSC NMR/MS (as needed) Purity Det.

Coin cell testing with sealed cells (EIS, cycL and/or calL, dQ/dV, redox shuttle? etc.) ARC Testing (SNL)

Post-mortem on electrodes and thermal stability samples.

6931

SM-6

100SM-7

2179

SM-5

1486

SM-4

3763

SM-3

6931

SM-2

3862

SM-1

100SM-0OR%Formulation

6931

SM-6

100SM-7

2179

SM-5

1486

SM-4

3763

SM-3

6931

SM-2

3862

SM-1

100SM-0OR%Formulation

INL SM Series of Phosphazenes

♦ Classes of non-flammable materials:

– Phosphorus-based: phosphates, phospholanes, phosphines, phosphazenes etc. – Borates – Pyrocarbonates, which release CO2 – Halogenated: fluorinated carbonates, fluorinated ethers – Silicon-based: siloxanes, silanes.

♦ For over a decade there have been many reports of studies directed at decreasing the flammability of Li-ion electrolyte. However, there is still no commercially available low-flammability electrolyte that has competitive transport properties and has been successfully applied in a battery.

♦ Most of studied compounds provide some safety benefit, however, seriously undermine the SEI-forming properties of Li-ion electrolytes which is an unacceptable cost to cell performance.

♦ We chose to work with phosphazenes because they appear to be less detrimental to required SEI properties and we hope to eliminate this negative effect by synthetic pathways with great variability of final molecular design.

Rationale for Working with Phosphazenes

3

Electrolyte Production Highlights • Amenable to production via continuous synthesis

– Not interrupted production (like batch, semi-batch processes) – Very high volume, low worker numbers – Most efficient chemical production method known

• Purification is extremely simple – Continuous counter-current aqueous extraction – Waste products low toxicity/very low disposal cost – Excess reagents easily recovered for reuse

• Required ultra-drying is unusually easy as the electrolyte is non-volatile and thermally very robust

Chemical Synthesis Capabilities • Over 3,000 ft2 of wet chemistry labs • Multiple fume hoods (11) and air-free synthetic manifolds • Focused on a variety of synthetic projects

– Electrolytes – Polymers – Membranes – Selective extractants

• The new 140,000 ft2 research laboratory facility (REL) scheduled for occupancy in 2012

We are working closely with ANL to initiate scale-up of INL phosphazene additives at their materials scale-up facility.