novel materials for batteries

1. Dr. H. S. GOUR UNIVERSITY SAGAR(M.P.)
Department of physics
A presentation on -
Novel materials for batteries
By-
RAJAN KUMAR SINGH
Guided by-
Dr. RANVEER KUMAR

2. CONTENTS
1. Novel electrodes for solid state batteries
(i) Introduction
(ii) Requirements for electrode material designing
2. The Lithium Carbon Electrode
2.1 Graphite
(i) Occurrence of Graphite
(ii) Properties of Graphite
(iii) Types of Graphite
a: Natural Graphite
b: Synthetic Graphite
c: Highly Oriented Pyrolytic Graphite(HOPG)
2.2 Graphite Intercalation Compounds(GICs)
(i) structure of GICs
(ii) types of GICs
(iii) formation of intercalation stages in GICs

3. CONTENTS…
3. Electrochemical intercalation of Li ion Carbon
4.Carbon – Na electrode
5. Materials for rechargeable Li batteries
(i) Introduction
(ii) Intercalation process
(iii) Rutile type material
(iv) Perovsikite type material
(v) Spinel type material

4. 1. Novel electrodes for solid state batteries
Introduction:
◙ In the recent years, a tremendous research work has developed to polymer
electrolytes operating near the ambient temp. , particularily for application in
solid state electrochemical devices such as:, Electro-chromic displays, sensors, super
capacitors and batteries.
◙ Li polymer electrolyte batteries are used in electric vehicle development so it is
huge market for EVD
◙ Electrode materials are based upon interaction compounds.
◙ Electrode materials has highly capabilities and electrode kinetics.

5. Requirement For Electrode Material Designing
Low working potential high specific capacity good electrolyte
interface

6. LithiumCarbonElectrode
Graphite:
•Most ordered carbon solid in 2-D structure.
•Thermodynamically most stable form of elemental carbon.
•Occurrence: Madagascar, Sri lanka, Brazil. China & India.
Types of Graphite
Natural
graphite
Synthetic
graphite(Edward
Goodrich) 1890
HOP G

7. Graphite forms in
metamorphosed
sedimentary rocks
as an alteration of
organic material.
publicdomain
marble
metamorphosed coal (anthracite)
quartzite
schist
gneiss
by-nc-sa:bcosti
by-nc-sa:RonSchott
by-nc-sa:brewbooks
by-nc-sa:brewbooks

8. ©TheodoreGray
©TheodoreGray
Soft and
greasy-feeling,
graphite is
usually found
in lumps…
Graphite is mined.
by-nc-nd:tridymite
by-nc-nd:tridymite
…but occasionally in crystals.

9. GRAPHITE
Metamorph rock

10. PropertiesofGraphite
Has a layered planar structure.
In each layer, the carbon atoms are arranged in a honeycomb lattice with
separation of 0.142nm & the distance between the plane is 0.335nm.
electrically conductive. (Semi- metal)
Due to weak Vander walls bond, graphite layer can be easily separated.
Two form of graphite: 1. alpha(α) (hexagonal)
2. beta (β) (rhombohedral)

11. Applications of graphite
1. Refractory
2. Batteries
3. Steel making
4. Brake linkage
5. Pencils

12. Graphite Furnace Atomic
Absorption Laboratory
Graphite can withstand high
heat.
Graphite crucibles of different
sizes. These crucibles can
withstand temperatures up to
1500°C.

13. Graphite is in generators, as
the carbon brushes that
conduct electricity.

14. Some paints
contain graphite.

15. Alkaline
batteries
contain
graphite rods.

16. Lightweight sports equipment,
like tennis racquets and golf
clubs, are often made from
graphite.
Graphite Lubricant

17. Graphite Intercalation Compounds
GICs are formed by injecting atomic/ molecular layer of other
chemicals within graphite host material.
Particularly physical interest due to it's high degree of order.
Most important and characterization properties is, staging
phenomenon.
GICs 1st reported by schaffaut in 1841 but systematic study
startrrd later on 1940s

18. Graphite Intercalation Compounds
 Complex material with formula CXm (as m < 1).
 At intercalation reaction of M species intercalating in to a host H is represented
by,
XM + H MxH
Types of GICs
Donor type
GICs
Acceptor
type GICs
Covalent &
semi-
covalent

19. 1.Doner Type GIC:
@Formed with highly reducing reactive i.e. alkali & alkali earth
metal.
@In this GICs, the carbon layer has a negative charges
e.g. Li+C-
6
2.Acceptor type GIC:
@ Formed by intercalation ions or by transition metal halides
or by other electron species such as Lewis acid.
@ It bears opposite sign of Donner type GICs i.e. carbon have
more positively charge.
@ Behave as metals (synthetic metals)
3.covalent & semi-covalentGIC:
Formed with highly oxidizing achives such as fluorine at high
temp. or strong acids & oxanions e.g. CFX & COxHy

20. Structure Of Lithium - GICs
LiC6 exhibit hexagonal unit cell belongs to apace group
P6/mmm with parameter a=4A0 & c =3.706A0
LiC12 have a=4.288A0 & c= 7.065A0.
Recently XRD study revels that presence of other superdence
plane , intermediate between LiC2 & LiC6 having 8.63A0 &
11.1A0 as a and c parameter respectively.

21. Properties of gic
Additional free carriers
High in-plane mobility of graphite
Higher in-plane conductivity
Donor: increased off-plane conductivity
Acceptor: increased off-plane resistivity
Only donor GICs exhibit superconductivity

22. Applications of GIC
Electro – chemical devices
Sensors
Photo – chemical devices
Electro-chromic devices
Superconductors
Catalysts

23. Materials for Rechargeable Li Batteries
Introduction:
The science of intercalation materials deals with electrical energy storage in
chemical or electrochemical form & this is the foundation for synthesizing a well
defined intercalation material that can be used as, an anode and cathode in a
rechargeable battery.
Intercalation materials are gaining prominence in electrochemical devices,
sensors & photochemical devices.
Due to technical application of intercalation materials in solid state ionic devices,
studied by solid state chemists, physicist & more important by material
engineering & process technology.

25. Li-ion batteries are
among the best
battery systems in
terms of energy
density (W-h/kg &
W-h/L). This makes
them very attractive
for hybrid
automobiles &
portable electronics

26. Cathode Materials Considerations
1. The transition metal ion should have a large work function (highly oxidizing) to
maximize cell voltage.
2. The cathode material should allow an insertion/extraction of a large amount of
lithium to maximize the capacity.
High cell capacity + high cell voltage = high energy density
3. The lithium insertion/extraction process should be reversible and should induce
little or no structural changes. This prolongs the lifetime of the electrode.
4. The cathode material should have good electronic and Li+ ionic conductivities.
This enhances the speed with which the battery can be discharged.
5. The cathode should be chemically stable over the entire voltage range and not
react with the electrolyte.
6. The cathode material should be inexpensive, environmentally friendly and
lightweight.

27. SPINEL TYPE MATERIALS
Li1-xMn2O4
Structure type is defect spinel
Mn ions occupy the octahedral sites, while
Li+ resides on the tetrahedral sites.
Rather poor electrical conductivity
Lithium de-intercalation varies from 0  x
 1, comparable to Li1-xCoO2
Presence of Mn3+ gives a Jahn-Teller
distortion that limits cycling. High Li
content stabilizes layer like structure.
Capacity ~ 36 A-h/kg
Voltage ~ 3.8 Volts
Energy density ~ 137 W-h/kg
Mn is cheap and non-toxic.

28. PEROVSKITE STRUCTURE
Ba2In2O5
The brownmillerite structure can be
derived from perovskite, by removing 1/6
of the oxygens and ordering the vacancies
so that 50% of the smaller cations are in
distorted tetrahedral coordination.
In Ba2In2O5 at 800 ºC the oxygen vacancies
disorder throughout the tetrahedral layer,
and the ionic conductivity jumps from 10-3
S/cm to 10-1 S/cm.
BaZrO3-Ba2In2O5 solid solutions absorb
water to fill oxygen vacancies and become
good proton conductors over the
temperature range 300-700 ºC.

29. SOME OTHER PEROVSKITECathode (Air Electrode)
(La1-xCax)MnO3 (Perovskite)
(La1-xSrx)(Co1-xFex)O3 (Perovskite)
(Sm1-xSrx)CoO3 (Perovskite)
(Pr1-xSrx)(Co1-xMnx)O3 (Perovskite)
Anode (H2/CO Electrode)
Ni/Zr1-xYxO2 Composites
Electrolyte (Air Electrode)
Zr1-xYxO2 (Fluorite)
Ce1-xRxO2 , R = Rare Earth Ion (Fluorite)
Bi2-xRxO3 , R = Rare Earth Ion (Defect Fluorite)
Gd1.9Ca0.1Ti2O6.95 (Pyrochlore)
(La,Nd)0.8Sr0.2Ga0.8Mg0.2O2.8 (Perovskite)
Interconnect (between Cathode and Anode)
La1-xSrxCrO3 (Perovskite)