CQMF - Cours inter- universités “Matériaux Fonctionnels”
Electrolytes solides
13 March 2013
Ana C. Tavares, INRS-EMT
1
Electrolytes Solides
• Quiz
• Fundamentals
– Electrochemical cells
– what is a solid electrolyte
– types of solid electrolytes
– …..
• Applications
– ZEBRA battery
– Solid oxide fuel cells
– Direct methanol fuel cells
– Electrolyser
– Electrodialysis
• Materials
– Na+ ion conductor
– O2- anion conductor
– H+ conductors (high T and
low T) vs. OH- conductors
(low T)
– Ionomers:
• Proton exchange
membranes
• Anion exchange
membranes
2
Solid state electrochemistry
Solid State Electrochemistry may be divided into two broad topics:
•
Solid electrolytes which conduct electricity by the motions of ions, and
exhibit negligible electronic transport
– Crystalline and amorphous inorganic solids
– Ion conducting polymers
•
Electrodes which conduct both ions and electrons
– Crystalline inorganic solids
– Conducting polymers
Li-ion battery
PEM fuel cell
3
ELECTROCHEMISTRY
e-
e-
Cathode
e-
e-
Anode
½ O2 + 2H+ + 2 e- → H2O
H2 → 2H+ + 2 e-
H+
Overall reaction: H2 + ½ O2 → H2O
Electrolyte
∆E°= 1.24 V at 25 ° C
Electrochemistry ⇒ electron transfer between an electrode and chemical species in a solution ⇒
interface
4
INTRODUCTION – Electrochemical device
∆E ° = -nF∆G°
H2O (l) → ½ H2 (g) + O2 (g)
½ H2 (g) + O2 (g) → H2O (l)
Galvanic
(electrochemical) cell
Electrolytic cell
∆G>0 ⇒ ∆E < 0
∆G<0 ⇒ ∆E > 0
Decomposition of chemical compounds by
A spontaneous redox reaction is used
means of electrical energy (electrolysis):
to create an electric current.
• water electrolysis (H2, O2)
• Batteries
• brine electrolysis (Cl2)
• Fuel cells
• electrorefining and electrowining of several
non-ferrous metals (Al (bauxite), Cu, Zn, Pb)
13 Janvier 2011
PaC (INRS-EMT) par A. Tavares
5
EQUILIBRIUM AND THE NERNST EQUATION
σ
c
RT
∆E e = E C − E A = ∆E 0e +
ln σO
nF c R
∆E 0e = E 0C − E 0A
∆E / ∆G
∆E 0e = 0.3402 − (−0.7628)
∆E = 1.103V
0
e
vs. HRE
???
∆E 0e = E 0C − E 0A
∆E 0e = 0.3402 − 1.229
∆E = −0.888V
0
e
vs. HRE
6
ELECTROCHEMICAL CELLS
http://en.wikipedia.org/wiki/Voltaic_pile
7
ELECTROCHEMICAL CELLS
• Production of aluminium, lithium, sodium, potassium, magnesium, calcium, copper
• Production of chlorine and sodium hydroxide
• Anodization is an electrolytic process that makes the surface of metals resistant to
corrosion. Decoration purposes….
• Electroplating
8
PORALIZABLE ELECTRODE vs NON POLARIZABLE ELECTRODE
- +
eeV
A
High
impedance
voltmeter
(current zero)
B
Current (j) ≠ 0:
-Polarizable electrode: the electron transfers through the DL is very difficult; if the number of
electrons is increased, they will accumulate at the interface and the potential will increase
(Hg, metal electrodes….)
- Non polarizable electrode: the electron transfers through the DL is very easy; the
electrons do not accumulate at the interface and the potential will remain constant
(reference electrodes….)
9
ELECTRON TANSFER: DEPARTURE FROM EQUILIBRIUM
- +
e-
∆E = −
eV
∆G
nF
Electrochemical conversion of energy
j≠0
A
B
η = E j − E eq
∆V = ∆E − Ση − ∆VΩ
∆V = ∆E − Ση
Sum
overpotentials
A&B
Ohmic drop=R.I
∆V = ∆E − Ση − ∆VΩ − ∆Vt
stability
10
DEPARTURE FROM EQUILIBRIUM
Electrolyser - ∆G >0:
load
e
_
∆V = (E 0C − E 0A ) + (ηC + ηA ) + RI + ∆V( t )
e
Power Source - ∆G <0:
+
∆V = (E 0C − E 0A ) − (ηC + ηA ) − RI − ∆V( t )
M
M’
Mn+
M’y+
Thermodynamic
reversible
potential (Nernst)
Overpotential
s
Stability term
Total Ohmic
losses
nature of reactions
nature of the electrodes
- ELECTROCATALYSIS -
cell and components
design and
operating conditions
11
DEPARTURE FROM EQUILIBRIUM
V
Electrolysers (+)
• maximum I, lower ∆V
Eeq
• maximum I, higher ∆V
Power sources (-)
I
∆V = ∆E ± Ση ± ∆VΩ ± ∆Vt
Cell design
Depends on the
electrode reactions
energy losses due
to activation energy
and concentration
profile
Materials chemistry and
physiscs
12
DEPARTURE FROM EQUILIBRIUM
Pathway of a general electrochemical reaction
13
ELECTROCHEMICAL CELLS
∆E 0e = E 0C − E 0A
∆E 0e = E 0C − E 0A
∆E 0e = 0.3402 − (−0.7628)
∆E 0e = 0.3402 − 1.229
∆E 0e = 1.103V
∆E / ∆G
∆E 0e = −0.888V
???
14
ELECTRICAL DOUBLE LAYER
Interface:
region where two different phases become in contact
15
ELECTRICAL DOUBLE LAYER
Interface:
region where two different phases
become in contact
16
Crystalline solid electrolytes
• Ionic conductivity occurs by means of ions hopping from site to site trough a
crystal structure
• It is necessary to have partial occupancy of energetically (near) equivalent
sites
Two broad classes of
conducting mechanism
Vacancy migration
Interstitial migration
The ionic conductivity, σ
σi = Ci ⋅ z i ⋅ µ i
ci concentration of mobile species i (interstitial or vacancies)
zi charge of species i
µi mobility of species i
17
Crystalline solid electrolytes
Vacancy migration:
Interstitial sites migration:
Vacancies are generated when a number of
sites that would be occupied in the ideal defect
free structure are empty (Schottky defect,
charged impurity).
An ion adjacent to a vacancy may be able to
hop into it leaving its own site vacant.
Interstitial sites are empty sites in an
ideal structure.
Occasionally in real structures ions may
be displaced from their lattice sites into
interstitial sites.
Schottky Defect in NaCl:
Na+ + Cl- → VNa + VCl
Frenkel Defect in AgCl:
Ag+ → VAg+ Ag+ interstitial
18
Crystalline solid electrolytes
The ionic conductivity, σ
σi = Ci ⋅ z i ⋅ µ i
Conductivity means many mobile ions
• A practical way to increase Ci is by means of doping with aliovalent (or
heterovalent) ions: formation of solid solutions.
There are four fundamental ionic mechanisms for achieving charge balance:
Doping with higher valent cations
Doping with lower valent cations
Cation vacancies
Anion interstitials
Cation interstitials
Anion vacancies
e.g. 3 Li+ = Al3+ in
Li4-3xAlxSiO4
e.g. Ca2+ = Y3+ + F- in
(Ca1-xYx)F2+x
e.g. P5+ = Si4+ + Na+
in
Na1+xZr2(P3-xSix)O12
2Zr4+ + O2- = 2Y3+
in
(Zr1-2xY2x)O2-x
The number of interstitials or vacancies increases with x.
19
Crystalline solid electrolytes
The activation energy ∆Hm is the major factor controlling the ionic mobility µ.
The Arrhenius expression for conductivity is
σ = A exp (-∆Hm/RT)
•
•
•
•
The activation energy ∆Hm represents the
ease of ion hopping.
It is related directly to the crystal structure
and in particular to the openness of the
conduction pathway.
Most ionic solids have densely packed
crystal structure with narrow bottlenecks and
consequentially with large activation energy
for hopping, usually 1 eV (96kJ/mole) or
greater and conductivity values are low.
In solid electrolytes open conduction
pathways exist and activation energy may be
much lower, as low as 0.03 eV as in AgI.
20
Inorganic solid electrolytes
•
Ag+ Ion Conductors (Ion selective electrodes)
– Ag2S - used in some ion selective electrodes
•
Na+ Ion Conductors
– Sodium β-Alumina (i.e. NaAl11O17, Na2Al16O25) - used as a membrane in several
types of molten salt electrochemical cells
– NASICON (Na3Zr2PSi2O12)
•
Li+ Ion Conductors (Li ion batteries)
– LiCoO2, LiNiO2, LiMnO2
•
O2- Ion Conductors (SOFCs, oxygen sensors)
– Cubic stabilized ZrO2 (YxZr1-xO2-x/2, CaxZr1-xO2-x),
– doped CeO2
– δ-Bi2O3
– Defect Perovskites (La1-xCaxMnO3-y, La1-xSrxCo1-yFeyO3-y,)
•
F- Ion Conductors (Ion selective electrodes)
– LaF3
•
H+ Ion conductors (High temperature H2 and direct methanol fuel
cells)
– CsHSO4
21
Solid Electrolyte Materials - β alumina (example 1)
Sodium beta alumina is a non-stoichiometric sodium aluminate
known for its rapid transport of Na+ ions.
The β-Al2O3 structures are layered structures in which densely
packed blocks with spinel-like structure alternate with open
‘conduction planes’ containing the mobile Na+ ions. The β and β”
structures differ in the detailed stacking arrangement of the spinel
blocks and conduction planes.
This material selectively passes Na+ ions while blocking other
species, including liquid sodium and liquid sulfur.
It is a ceramic which can be formed and sintered by commercially
available techniques and its conductivity at operating temperatures
— 250 to 300 C — compares favorably with electrolytes used in
conventional battery systems such as sulfuric acid and potassium
hydroxide.
22
Solid Electrolyte Materials: β and β’ alumina
(example 1)
23
Solid Electrolyte Materials: β and β’ alumina
(example 1)
the conductivity of polycrystalline β/β’’-Al2O3, depends on: (i) composition; (ii) relative
proportion of and phases present; and (iii) microstructure (grain size, porosity,
impurities, etc.).
24
Solid Electrolyte Materials: β and β’ alumina
(example 1)
Single cell tubular design ZEBRA batteries
The ZEBRA battery operates at 300-350 °C and utilizes β-alumina as
electrolyte and molten sodium chloroaluminate (NaAlCl4, melting point of
157 °C), as the secondary electrolyte.
The negative electrode is molten sodium.
The positive electrode is nickel in the discharged state and nickel chloride
in the charged state.
• Specific energy 90 Wh/kg and power (150 W/kg).
• LiFePO4 lithium iron phosphate batteries store 90–110 Wh/kg and the more common
• LiCoO2 lithium ion batteries store 150–200 Wh/kg.
25
Solid Electrolyte Materials: β and β’ alumina
(example 1)
Single cell tubular design ZEBRA batteries
•The primary elements used in the manufacture of ZEBRA
batteries, Na, Cl and Al have much higher worldwide reserves.
• Lifetimes of over 1500 cycles and five years have been
demonstrated with full-sized batteries, and over 3000 cycles and
eight years with 10- and 20-cell modules.
• Vehicles powered by ZEBRA batteries have covered more
than 2 million km.
The sodium nickel chloride battery (or ZEBRA battery, so-called for the Zeolite Battery
Research Africa Project) has been under development for almost 20 years, and is now
26
entering the commercialization phase.
Solid Electrolyte Materials: β and β’ alumina
(example 1)
27
Solid state devices - Solide Oxide Fuel Cells
(example 2)
• High temperature needed in SOFC are due at the low ionic conductivity of the
electrolyte at low temperature.
28
Solid state devices - Solide Oxide Fuel Cells
(example 2)
29
Solide Oxide Fuel Cells main features (example 2)
•
All solid state device
•
High temperature operation
– Multiple fuel possibility if combined with the right amount of water (internal reforming)
– Direct process of the fuel in the fuel cell
– Expensive catalysts are not necessary
•
High efficiency
– Small electronic conductivity and gas crossover
– But low thermodynamic efficiency than PEM
•
Tolerance to impurity
– No CO poisoning
– But some materials design have poor tolerance for sulfur
•
Simple design of MEA
– Absence of liquid phase in the electrodes (flooding, catalyst wetting)
–
•
No need of water management
Suitable for cogeneration
– Residential and small stationary plant generation
30
Crystalline Solid Electrolytes for SOFC (example 2)
General requirements for a SOFC electrolyte are:
• high ionic conductivity
• low electronic conductivity,
• stability in both oxidizing and reducing environments
(gradient in the oxygen partial pressure across the cell from 0.2 atm on the air side to 1x10-15 to 1 x10-20
atm on the fuel side)
• good mechanical properties and long-term stability with respect to dopant
segregation.
State of the art electrolytes:
• YSZ (yttria stabilized zirconia)
• CGO / SDC (gadolinia / samaria doped ceria)
• Sr Mg-doped LaGaO3 gallate (La0.9Sr0.1Ga0.8Mg0.2O2.85)
31
Crystalline Solid Electrolytes for SOFC (example 2)
• YSZ - ZrO2 doped with 8-10 mole % of Y2O3
Zr(Y)
O
(CaF2-Typ)
• Doping ZrO2 (Zr1-xYxO2-x/2, Zr1-xCaxO2-x) fulfills two purposes:
• Introduces anion vacancies (lower valent cation needed)
• Stabilizes the high symmetry cubic structure (larger cations are most effective)
32
Crystalline Solid Electrolytes for SOFC (example 2)
• 1-2 mol% Gd2O3 (Sm2O3) doped CeO2
• right cube - undoped CeO2
• left cube, two of the cerium ions are replaced by trivalent ions from the
lanthanide series (dark spheres), between which an oxygen vacancy
appears (indicated by a small sphere).
33
Crystalline Solid Electrolytes for SOFC (example 2)
• LaGaO3
• La0.9Sr0.1Ga0.8Mg0.2O3-δ
• left - undoped LaGaO3
• right – La3+ and Ga3+ ions are replaced by bivalent Sr2+ and Mg2+ ions
generating oxygen vacancies.
34
Crystalline Solid Electrolytes for SOFC (example 2)
Reduce the operating temperature
down to 400-500 °C:
• Allows to use less expensive
materials (steel) for current collector,
interconnections, gas diffusers and
other critical components
• Reduce the start up time
• Cost reductions
• Increase the lifetime and allow multiple
startup and shutdown (thermal stress)
If we assume a film thickness of 10 μm and a conductivity of 1x10-2 S cm-1 (ASR=0.1 Ωcm2),
then the minimum operating temperatures are:
∼700 C (YSZ), ∼550 C (LSGM), and ∼550 C (CGO) based on the data in the Figure.
35
Other Electrolytes for Fuel Cells
36
CsHSO4 for Direct Methanol Fuel Cells (example 3)
• CsHSO4 is a solid acid, a compound whose
chemistry and properties are intermediate between
those of a normal acid (e.g. H2SO4) and a normal
salt (e.g. Cs2SO4).
• CsHSO4 transforms from a monoclinic to a
tetragonal (disordered) structure at 141 °C.
• This transformation is accompanied by an
increase of conductivity by a two, three order of
magnitude reaching value as high as 10-2 ohm-1
cm-1.
• Both the transition and the ion transport
are commonly referred as “superprotonic”.
37
CsHSO4 for Direct Methanol Fuel Cells (example 3)
S.M. Haile et. al. Science, 303 , 68, (2004)
38
Solid state electrochemistry
•
Solid electrolytes which conduct electricity by the motions of ions, and
exhibit negligible electronic transport
– Crystalline and amorphous inorganic solids
– Ion conducting polymers (ionomers)
• Proton exchange polymers (e.g. Nafion)
• Anion exchange membranes (e.g. Neosepta)
•
Ion conducting polymers – H+ conductors
• Proton is unlikely to conduct in the same way as other ions:
• Small size
• High polarizing power
•
Various mechanisms have been proposed: vehicular and Grotthuss
mechanisms
• The passage of protons along H-bonded networks and a combination of H+
transferring between adjacent water molecules, linked to rotation of H3O+ groups as
a means of proton transfer to the next water molecule.
39
Ion conducting polymers – H+ conductors
Perfluorinated ionomers
•
•
Chemically highly resistant
Mechanically strong ⇒ be made
into very thin films (down to 50
µm)
•
•
Very acidic materials
Can absorb large quantities of
water
If well hydrated, the protons can
move freely within the
membrane – excellent proton
conductors
•
40
Ion conducting polymers – H+ conductors
Perfluorinated ionomers – how does it work?
• strong attraction between SO3- and H+ ions of each branch ⇒ the side chains
tend to cluster within the overall structure of the material
Microphase separated
morphology
• sulphonic acid is highly hydrophilic ⇒ creation of hydrophilic regions within an
hydrophobic material
• hydrophilic regions: H+ ions are relatively weakly attracted to the SO3- groups –
and are able to move (diluted acid)
41
Ion conducting polymers – H+ conductors
Cluster Model
Ionic Cluster –sulfonic acid + water + counter ion
42
Ion conducting polymers – H+ conductors
Hydrated Nafion – Yeager three zones model
three different domains characterized by
water clusters connected through channels
Region A: fluoropolymer backbone (compact
and hydrophobic).
Regione B: interface between A and C, where
some water and sulfonic groups exist.
Region C: formed by the water clusters and
lager concentration of sulfonic acid groups.
Well hydrated Nafion:
20 H2O molecules for each SO3- side chain
given a typical conductivity of 0.1 S/cm.
43
Ion conducting polymers – H+ conductors
Proton conduction mechanism – membrane hydration
44
Ion conducting polymers – H+ conductors
Proton conduction mechanism – membrane hydration
45
Ion conducting polymers – H+ conductors
Proton conduction mechanism – membrane hydration
46
Ion conducting polymers – H+ conductors
Proton conduction mechanism - Grotthuss mechanism
• Also called “hopping” mechanism
• Stationary vehicles (only local motion)
• Proton “hops” from vehicle to vehicle
• Always within H bond environment
• Solvent reorientation –provides H+
pathway
• Continuous motion
• the Grotthuss mechanism explains the
unusually high equivalent proton cond
in diluted solutions.
47
Solid state devices – Electro-membrane processes
BRINE ELECTROLYSIS - Production of Cl2 and NaOH solution by electrolyzing an
aqueous solution of NaCl (brine). The primary products of electrolysis are Cl2, H2, and NaOH
solution.
• Cl2 and NaOH are among the
top ten chemicals produced in
the world and are involved in the
manufacturing of
pharmaceuticals, detergents,
deodorants, disinfectants,
herbicides, pesticides, and
plastics.
48
H+ exchange membranes & Brine electrolysis
(example 4)
Electrochemical and chemical reactions occurring in mercury cells
2Cl- ==> Cl2 + 2e-
(anodic reaction)
2Na+ + 2Hg + 2e- ==> 2Na (in Hg)
(cathodic reaction)
2Cl- + 2Na+ + 2Hg ==> Cl2 + 2Na (in Hg)
(overall cell reaction)
2Na (in Hg) + 2H2O ==> H2 +2NaOH + Hg
(decomposer reaction)
2NaCl + 2H2O ==> Cl2 +2NaOH + H2
(overall process reaction)
49
H+ exchange membranes & Brine electrolysis
(example 4)
• Mercury cell
• Diaphragm cell
• Ion exchange membrane cell
50
H+ exchange membranes & Brine electrolysis
Electrochemical and chemical reactions occurring in diaphragm and membrane cells
(anodic reaction)
2Cl- ==> Cl2 + 2e(cathodic reaction)
2H2O + 2e- ==> 2OH- + H2
(overall ionic reaction)
2Cl- + 2H2O ==> Cl2 + H2 + 2OH(overall reaction)
2NaCl + 2H2O ==> Cl2 +2NaOH + H2
(side reaction)
Cl2 + 2NaOH ==> NaOCl + NaCl + H2O
(side reaction)
3NaOCl ==> NaClO3 + 2NaCl
Perfluorinated bilayer membrane:
• Electrolysis conditions in chlor-alkali process are too severe for hydrocarbon based
ion exchange membranes:
• one surface of the membrane contacts caustic soda of high concentration and the
other chlorine gas (both at more than 80 “C).
• high electrical current is passed through the membrane (20-60 A dm-2).
• Perfluorocarbon sulfonic acid membranes show low current efficiency in caustic soda
production in the electrolysis of sodium chloride solution due to the high water content of the
membrane
• Cation exchange membranes having carboxylic acid groups show high current efficiency in
caustic soda production
• Composite membranes composed of a thick layer having sulfonic acid groups and a
thin layer having carboxylic acid groups are a practical compromise to achieve high
51
performance in electrolysis (bilayer membrane).
Solid state devices – Electro-membrane processes
BRINE ELECTROLYSIS
52
H+ exchange membranes & Brine electrolysis
Chlor/alkali manufacturing
Chlorine cell technology in the U.S.
Operating current density ( kA/m2)
Cell voltage (V)
NaOH strength (wt%)
Energy consumption ( kWh/MT Cl2) at a
current density of (kA/m2)
Steam consumption (kWh/MT Cl2) for
concentration to 50% NaOH
Mercury
Diaphragm
Membrane
8 - 13
0.9 - 2.6
3-5
3.9 - 4.2
2.9 - 3.5
3.0 - 3.6
50
12
33-35
3360 (10)
2720 (1.7)
2650 (5)
0
610
180
53
Anion (OH-) exchange membranes
• AEXM are based cross-linked polystyrene functionalised with quaternary amines
bonded to polyethylene, ETFE or PEF backbones.
• Wide variety of commercial AEXM under different trade names, and sold by Solvay,
Pall, 3M, Asahi Glass….
• Electrodeionization for ultrapure water
• Electrocoating for Cathodic and Anodic paint systems
• Electrodialysis for desalination and demineralization
• Electroplating for metal recovery
• Electrolysis
54
Anion (OH-) exchange membranes
55
Solid state devices – Electro-membrane processes
ELECTRODIALYSIS – transport of salt ions from one solution to another solution
through ion-exchange membranes under the influence of an applied electric
potential difference.
Electrodialysis is usually applied to deionization of aqueous solutions, and some
applications of electrodialysis include:
– Large scale brackish and seawater desalination and salt production.
– Small and medium scale drinking water production (e.g., towns & villages,
construction & military camps, nitrate reduction, hotels & hospitals)
– Water reuse (e.g., industrial laundry wastewater, produced water from oil/gas
production, cooling tower makeup & blowdown, metals industry fluids, wash-rack
water)
– Pre-demineralization (e.g., boiler makeup & pretreatment, ultrapure water
pretreatment, process water desalination, power generation, semiconductor,
chemical manufacturing, food and beverage)
– Food processing
– Agricultural water (e.g., water for greenhouses, hydroponics, irrigation, livestock)
56
Water desalination
Grands Lacs (Canada)
18% de la reserve mondiale de
l’eau (avec le St-Laurent).
Perth, Australia (RO)
57
Water desalination
58
Water desalination
• Freshwater drawn from the groundwater source requires 0.14–0.24 kWh/m3 for a
pumping head of 120–200 ft.
•Treatment of surface waters to potable quality requires 0.36 kWh/m3 to produce
freshwater.
•The cost of freshwater supply through conventional treatment is less than $0.25/m3.
59
Water desalination
•
•
•
The two primary methods of desalination are thermal distillation and membrane
processes
Membranes are the more practical in terms of cost and environmental impact
The two primary membrane methods of water desalination are reverse osmosis
(RO) and electrodialysis (ED)
Reverse Osmosis:
A process by which a solvent such as water
is purified of solutes by being forced through
a semipermeable membrane through which
the solvent, but not the solutes, may pass.
60
Water desalination and electrodialysis
Electrodialysis (ED) is the transport of salt ions from one solution to another through ionexchange membranes and under the influence of an applied electric potential difference.
Anode and Cathode Reactions
H2O → 2 H+ + ½ O2 (g) + 2eor 2 Cl- → Cl2 (g) + 2e2e- + 2 H2O → H2 (g) + 2 OH-
• The cations of the dissociated salt components in water solution move towards the cathode
pass through the cation exchange membranes
• The anions drawn to the anode pass through the anion exchange membrane but stop at the
cation exchange membranes.
• Using the right combination of anion exchange and cation exchange membranes we can
separate the ions in the inlet solution and create a desalted flow called diluate, and
61
concentrated flow called concentrate.
Water desalination and electrodialysis
• Electrodialysis requires a lower level of water pretreatment process, reduced membrane
replacement frequency and energy costs as compared to reverse osmosis,
• However, the membranes involved in ED are highly sensitive and have a greater tendency
to fouling.
62
Bibliography (selection):
•
Xiaochuan Lu, Guanguang Xia, John P. Lemmon, Zhenguo Yang, Advanced
materials for sodium-beta alumina batteries: Status, challenges and perspectives
Journal of Power Sources 195 (2010) 2431–2442
•
J. L. Sudworth, A. R. Tilley, The sodium sulfur battery, Springer, 1985 - 447 pages
•
Lorenzo Malavasi, Craig A. J. Fisherb and M. Saiful Islam, Oxide-ion and proton
conducting electrolyte materials for clean energy applications: structural and
mechanistic features Chem. Soc. Rev., 2010, 39, 4370–4387
•
Michael A. Hickner Ion-containing polymers: new energy & clean water, 13 (2010) 34
•
Bart Van der Bruggen , Carlo Vandecasteele, Distillation vs. membrane filtration:
overview of process evolutions in seawater desalination, Desalination 143 (2002)
207-2 18
•
Veera Gnaneswar Gude a, Nagamany Nirmalakhandan b, Shuguang Deng
Renewable and sustainable approaches for desalination Renewable and Sustainable
Energy Reviews 14 (2010) 2641–2654
63