Molten Salt Batteries For Grid Storage of Energy
(Integrated PhD / PhD)
Support: YÖK 100/2000
The topic offered  by : Tayfur Öztürk
e-mail: ozturk [at]metu.edu.tr
Where to apply: Metallurgical and Materials Engineering  or  Micro Nanotechnology

 Abstract
NaS and NaNiCl2 (Zebra)   batteries are well known examples of batteries that operate at temperatures around 250-300 ^oC.  Such batteries make use liquid electrodes.  The  electrolyte, however,  is  solid (normally beta alumina). An alternative to such batteries would be all liquid state batteries where anode, cathode and  electrolyte are all  in liquid state, separated from one another merely by their density difference.  In this study the aim is to select anode, cathode and electrolyte materials that would operate at as low a temperature as possible with large discharge  capacity with fast kinetics. We will first start with the classical NaS battery and replace the solid electrolyte with the liquid one.

MnO₂ as Positive Electrode in Rechargeable Alkaline Batteries
(Integrated PhD/ PhD)
Support: YÖK 100/2000
The topic offered  by : Tayfur Öztürk
e-mail: ozturk [at]metu.edu.tr
Where to apply: Metallurgical and Materials Engineering or  Micro Nanotechnology

Abstract
Rechargeable alkaline batteries  are low cost alternative for grid storage of energy. MnO2 ,well known positive electrode in primary alkaline batteries,  can be used in researchable batteries also, provided that  the reaction   MnO2à MnOOH àMn(OH)2 could be fully reversed. These reactions in two steps  would  deliver a discharge capacity of 616mAh/g. This   is twice the discharge capacity of common positive electrode in alkaline batteries. There are however problems with the reversibility of  the second step, i.e. MnOOH  àMn(OH)2 . The study  will concentrate on this reaction and identify structural origin that make this reaction  irreversible.   MnO2 will be modified  by different oxides using the combinatorial approach  and   the conditions of full reversibility will be   determined  together with their electrochemical performance.

Mg@C as negative electrode material  for  rechargeable  batteries
(Integrated PhD/ PhD)
Support: YÖK 100/2000
The topic offered  by : Tayfur Öztürk
e-mail: ozturk [at]metu.edu.tr
Where to apply: Metallurgical and Materials Engineering /Micro Nanotechnology

Abstarct
We have an expertise in producing  nano Mg particles   wrapped  with   graphitic envelope. This  study will establish the potential  of such material as negatif electrode material for  rechargeable batteries. We will first examine  the potential of this material as negative electrode material  in  NiMH batteries. If reversibly hydrided, such electrodes would improve the discharge capacity to 4-6 times of that of AB5 compounds normally used for the purpose.  The work will then continue with Mg-ion batteries where Mg-graphite composite will again be  used as  negative electrode.

Surface coated Mg based negative  electrode materials  for  NiMH Batteries
(PhD)
The topic offered  by : Tayfur Öztürk
e-mail: ozturk [at]metu.edu.tr
Where to apply: Metallurgical and Materials Engineering

Abstract
Mg based alloys could have a discharge  capacity of well over 800 mAh/g, but subject to fast capacity decay in alkaline environment. This is due  to the formation of Mg(OH)2 which is claimed to be impermeable to hydrogen. This study explores the possibility of surface coating of Mg based active material as a method of preventing/controlling the Mg(OH)2 formation. Both polymeric and metallic coatings will be employed and conditions improving the cyclic stability will be identified. How coating influences the kinetics of electrochemical processes will also be studied.

Design and construction of 6 kWh NiMH battery pack  for home  storage of electricity
(M.Sc.)
The topic offered  by : Tayfur Öztürk and EE
e-mail: ozturk [at]metu.edu.tr
Where to apply: Metallurgical and Materials Engineering

abstract
The purpose of this study is to construct a unit that will have a capacity of   6 kWh using components that are available from the market. The study involves selection of basic units and integration of these into a complete unit with proper controls

Alloy design  for capillary membranes for hydrogen separation
(Integrated PhD/PhD)
Support: TÜBİTAK ( expected)
The topic offered  by : Tayfur Öztürk
e-mail: ozturk [at]metu.edu.tr
Where to apply: Metallurgical and Materials Engineering

 Abstract
This project aims to develop low-cost dense metallic membranes for hydrogen purifiers that could be used to produce high purity hydrogen from a gas mixture containing hydrogen. Dense metallic membranes in question are those with face centered cubic structure as these have already been proved to be suitable for commercial practice. The object is to obtain permeability levels similar to those achieved in commercial Pd-Ag membranes but with a substantial reduction in their Pd content. Targets set are  a permeability value of 3×10-8 mol/m.s.Pa0.5 at 350 °C and the Pd content of no more than %55 (commercial membranes have 77 Pd%).

Fabrication  of capillary membranes for hydrogen separation
(M.Sc.)
Where to apply: Metallurgical and Materials Engineering
Support: TÜBİTAK (expected)
The topic offered  by : Tayfur Öztürk
e-mail: ozturk [at]metu.edu.tr

This topic runs in parallel and compliments the topic given above and aims to fabricate capillary membranes for hydrogen separation purposes. First, the well known commercial composition Ag-77%Pd will be considered and the membrane will be fabricated in the form of capillary tube.  This would involve melting and casting of the alloy and rolling them into thin sheet. This is then deep-drawn into a cup and into a capillary tube by drawing.  Having identified conditions best suited for the purpose, a novel alloy developed  in the work depicted above  will be fabricated and  its  permeability will be measured.