Developing High Capacity, Long Life anodes

K. Amine (P.I)A. Abouimrane, D. Dambournet, and I. Belharouak,

Argonne National Laboratory

DOE merit reviewMay 09, 2011

Project ID # ES020This presentation does not contain any proprietary, confidential, or otherwise restricted information.

Overview

• Start - October 1st, 2009.• Finish – September 2014• 50% complete

• Safety of the battery.• Power density of the battery.• Cycle & calendar life span of the

battery.

• Total project funding: 900K

– FY11: 300K

– FY10: 300K

– FY09: 300K

Timeline

Budget

Barriers

• P. Chupas, K. Chapman, Y. Ren Advanced Photon Source, (APS/ANL).

• Z. Fang (University of Utah).• FMC, Northwestern University,

Partners

Develop new advanced high energy anode materials withlong life and improved Safety for PHEV and EV applications.

Objectives

Develop a low cost synthesis methods to prepare high energy anodes

Full structural and electrochemical characterizations of the prepared anode materials.

Demonstrate the applicability of these anodes in half and full cells systems.

Approaches MO-SnxCoyCz (MO=SiO, SiO2, SnO2, MoO2, GeO2) anode materials were

selected for investigation as high energy anode based on the followingcriteria:• SnxCoyCz alloys are known to provide a capacity of 400-500mAh/g for hundreds of

cycles.

• MO anodes are known to provide more than 1000 mAh/g with poor cyleability.

• The formation of SnxCoyCz and MO composite could lead to the increase in thecapacity, reduce the amount of cobalt in the material and improve the cyleablity asSnxCoyCz play the role of buffers against the volume expansion of MO.

• This anode system is more safer than the graphite and possess low potentials in therange of 0.3-0.75V (expect high voltage cells when combined with high cathodes)

• This anode system could offer higher practical capacity and higher 1st cycle chargedischarge efficiency

• This anode system offers high packing density (up to 3 g/cc), much higher than graphite(1.1g/cc) ( except higher volumetric density)

Milestones FY 10 : High capacity and Long Life Anodes

Some of the composite anode were prepared by mechanically alloyingusing metal (Co, Sn) carbon and oxides (MO). (Completed)

Comparative studies between MO-SnxCoyCz (MO=SiO, SiO2, SnO2, MoO2,GeO2) based on their electrochemical properties and their cost.(Completed)

Investigation of their structural rearrangement during the intercalationor de-intercalation of lithium. (On going)

Selection of a candidate for further electrochemical characterization:full cells study and HPPC tests. (On going)

Improvement of the 1st cycle charge discharge efficiency. (On going)

All materialswere prepared using a high energy ball milling.

Preparation of 50 wt% MO – 50 wt% Sn30Co30C40(MO= MoO3, SnO2, GeO2, SiO2, SiO) materials

10 20 30 40 50 60 70 802θ (º)

MoO2

10 20 30 40 50 60 70 802θ (º)

SnO2*

* Sample holder

10 20 30 40 50 60 70 80

* Sample holder

2θ (º)

GeO2

*

10 20 30 40 50 60 70 802

3

2θ (º)

SiO2

XRD shows that the SnO2 structure was conserved, MoO3 was reduced to MoO2 and no trace of GeO2 is present confirming the composite structure.

10 20 30 40 50 60 70 80

2θ (º)

SiO

Densities of 50 wt% MO – 50 wt% Sn30Co30C40(MO= MoO3, SnO2, GeO2, SiO2, SiO)

Material

50 wt% MO – 50 wt% Sn30Co30C40

Tap density

g/cc

True density

g/cc

MO = MoO3 2.74 6.05

MO = SnO2 3.02 7.13

MO = GeO2 2.62 5.06

MO = SiO2 1.43 3.58

MO = SiO 1.89 3.78

Materials based on tin, molybdenum and germanium have the highest tap density. Materials based silicon and tin are the cheapest.

Voltage profile and cycleability 50 wt% MO – 50 wt% Sn30Co30C40 (MO= MoO3)

0 200 400 600 800 1000 12000.0

0.5

1.0

1.5

2.0

2.5

3.0

Volta

ge

Capacity (mAh/g)

MoO3 Cycle 1 MoO3 Cycle 2 MoO3-SnCoC Cycle 1 MoO3-SnCoC Cycle 2

The laminate is prepared by using 80% active material 10% Acetylene black and 10% Polyimide binder.

Battery are cycled between 5mV and 2.5V.

A Voltage ~ 0.6V higher than the graphite was observed. High Voltage means less Li- plating and better safety.

The composite material cycles far much better than the MoO3 oxide alone.

0 20 40 60 80 100

200

400

600

800

1000

1200

1400

MoO3

50wt%MoO3-50wt%Sn30Co30C40

Capa

city

(mAh

/g)

Cycle number

Cycles 1 & 2 at 50mA/g (5mV-2.5V)From cycles 3 at 300mA/g

0 20 40 60 80 100 120 140 160 180 2000

200

400

600

800

1000

1200

Capa

city

(mAh

/g)

Cycle number

Charge Capacity Discharge Capacity

MoO3-Sn30Co30C40 PIVS (300mA/g)

~ 0.625/cm2

0 50 100 150 2000

200

400

600

800

1000

1200

MoO3-Sn30Co30C40 PIVS (300mA/g)

Active material ~ 1.35/cm2

Charge Discharge

Capa

city

(mAh

/g)

Cycle number

580

A capacity near 580 mAh/g is delivered after 200 cycles under 300 mA/g current rate (over C/2 rate).

1st cycle effeciecy~70%.

The capacity changes with the active material loading.

With low active loading, a capacity of 800 mAh/g can be reached.

Cycleability and effect of loading on 50 wt% MO – 50 wt% Sn30Co30C40 (MO= MoO3)

Good cycling with high coulombic efficiency after the first cycle.

50 wt% MoO3 – 50 wt% Sn30Co30C40 anode showed superior rate capability, i.e. 325 mAh/g capacity under a 7~8C rate.

0 5 10 15 20 25 300

200

400

600

800

1000

1200

1400

50

100

200400

8001200

16002000

Capa

city

(mAh

/g)

Number Of Cycles

Charge Discharge

2400

Current

(mA/g)

Capacity

(mAh/g)

100 610

200 565

400 515

800 460

1200 415

1600 375

2000 335

2400 325

Rate capability of 50 wt% MO – 50 wt% Sn30Co30C40(MO= MoO3)

Voltage profile and cycleability of 50 wt% MO – 50 wt% Sn30Co30C40 (MO= SnO2)

0 50 100 150 2000

400

800

1200

1600

2000

SnO2

Charge Discharge Charge Discharge

Capa

city

(mAh

/g)

Cycle number

50wt%SnO2-50wt%Sn30Co30C40

A Voltage ~ 0.75V, higher than the graphite that provide better safety and no lithium plating

The composite shows a capacity of 400 mAh/g for more than 150 cycles with moderate capacity fade under 300mA/g current rate.

1st cycle effeciecy~65%.

The composite material cycles better than the SnO2 oxide alone.

0 500 1000 1500 20000.0

0.5

1.0

1.5

2.0

2.5

Volta

ge

Capacity (mAh/g)

SnO2 Cycle 1 SnO2 Cycle 2 SnO2-SnCoC Cycle 1 SnO2-SnCoC Cycle 2

0 5 10 15 20 25 300

200

400

600

800

1000

1200

1400

50

100200

400600

8001000

Capa

city

(mAh

/g)

Cycle number

Charge Discharge

1200

Current

(mA/g)

Capacity

(mAh/g)

100 510

200 455

400 410

600 371

800 342

1000 332

1200 316

Rate capability of 50 wt% MO – 50 wt% Sn30Co30C40(MO= SnO2)

Good cycling with high coulombic efficiency (1st cycle irreversibility is about 65% due to the formation of Li2O which is not active in the case of SnO2-Sn30Co30C40 composite).

50 wt% SnO2 – 50 wt% Sn30Co30C40 anode showed superior rate capability, i.e. 316 mAh/g capacity under a 4C rate.

0 500 1000 1500 20000.0

0.5

1.0

1.5

2.0

2.5

Volta

ge

Capacity (mAh/g)

GeO Cycle 1 GeO Cycle 2 GeO-SnCoC Cycle 1 GeO-SnCoC Cycle 2

0 20 40 60 80 100 120

0

500

1000

1500

2000

2500

GeO2

Charge Discharge Charge Discharge

Capa

city

(mAh

/g)

Cycle number

50wt%GeO2-50wt%Sn30Co30C40

A Voltage ~ 0.5V higher than the graphite was observed

The composite shows a capacity of 800-1000 mAh/g for 100 cycles with moderate capacity fade under 300 mA/g current rate.

1st cycle charge discharge effeciecy~80%.

The composite material cycles better than the GeO2 oxide alone with much higher 1st

cycle charge-discharge efficiency.

Voltage profile and cycleability of 50 wt% MO – 50 wt% Sn30Co30C40 (MO= GeO2)

0 20 40 60 80 1000

200

400

600

800

1000

SiO2

50wt%SiO2-50wt%Sn30Co30C40

Capa

city

(mAh

/g)

Cycle number

DischargeChargeDischargeCharge

Cycles 1 & 2 at 50mA/g (5mV-2.5V)From cycles 1 (5mV-1.5V)

0 200 400 600 8000.0

0.5

1.0

1.5

2.0

2.5

3.0

Volta

ge

Capacity (mAh/g)

SiO2-SnCoC Cycle 1 SiO2-SnCoC Cycle 2 SiO2 Cycle 1 SiO2 Cycle 2

Voltage profile and cycleability of 50 wt% MO – 50 wt% Sn30Co30C40 (MO= SiO2)

A Voltage ~ 0.5V higher than the graphite with MO=SiO2

SiO2 alone is not electrochemically active.

The composite shows a capacity of 432 mAh/g for 100 cycles with outstanding charge discharge efficiency when it cycled between 5mV and 1.5V under 100 mA/g current using only a PVDF binder.

1st cycle effeciency~64%.

0 500 1000 1500 2000 25000.0

0.5

1.0

1.5

2.0

2.5

3.0

Volta

ge

Capacity (mAh/g)

SiO Cycle 1 SiO Cycle 2 SiO-SnCoC Cycle 1 SiO-SnCoC Cycle 2

0 50 100 150 2000

500

1000

1500

2000

2500

SiO

Charge Discharge Charge Discharge

Capa

city

(mAh

/g)

Cycle number

50wt%SiO-50wt%Sn30Co30C40

Voltage profile and cycleability of 50 wt% MO – 50 wt% Sn30Co30C40 (MO= SiO)

A voltage ~0.5V higher than that of graphite.

A capacity near 580 mAh/g is delivered after 130 cycles under 300 mA/g current rate between 5mv and 1.5V

1st cycle charge-discharge effeciecy~79% is better than SiO alone (only 67%).

Summary

MO-SnxCoyCz (MO = SiO, SiO2, SnO2, MoO2, GeO2) system was prepared bymechanically alloying using a high energy ball milling.

MO-SnxCoyCz system where (MO = SiO, SiO2, SnO2) are the most competitivesystem in term of cost.

50wt% SnO2 - 50wt% Sn30Co30C40 system provides the higher tap density butsuffers from the first cycle irreversibility ( near 65% ).

50wt% SiO - 50wt% Sn30Co30C40 system shows promising properties in termsof cost, tap density, capacity, cycleability and 1st cycle charge discharge efficiency.

Future Works Investigate of MO-SnxCoyCz (MO = SiO, SiO2, SnO2, MoO2, GeO2) system in fullcell configuration.

In-situ structural characterizations of MO-SnxCoyCz (MO = SiO, SiO2, SnO2,MoO2, GeO2) system with APS (Dr. Ren ).

Ex-situ PDF characterizations with APS (Dr. Chupas).

Surface characterization of lithiated anode materials by XPS with UtahUniversity (Dr. Fang).

Investigate the pulse-discharge and charge performance of designed cell basedon MO-SnxCoyCz (MO = SiO, SiO2, SnO2, MoO2, GeO2) system anode throughhybrid pulse power characterization (HPPC test).

Understand the causes of the first cycle charge discharge irreversibility and tryto reduce it.

Collaborations

A. Tressaud & A. Demourgues (ICMCB, Bordeaux, France)

FMC corporation

PJ. Chupas, and Y. Ren Advanced Photon Sources, Argonne

Z. Fang University of Utah.

Provisional application- New Silicon-based anode material, A. Abouimrane, K. Amine, (IN-10-013).

Patents