DESIGN OF A MULTILAYER ELECTROCHEMICAL DEVICE

1
DESIGN OF A MULTILAYER ELECTROCHEMICAL
DEVICE FOR USE AS AN OXYGEN GENERATOR OR SOLID
OXIDE FUEL CELL Manuel A. Alvarez,
PhD. madmanny_at_rci.rutgers.edu
OPTIMISATION OF MEMBRANES USED AS ELECTROLYTES IN
PROTON EXCHANGE FUEL CELLS Francoise Damay,
Ph.D. fdamay_at_ci.rutgers.edu.com
Proton exchange membrane fuel cells (PEMFC)
are mainly designed for small unit power plants
(vehicles, residential, battery recharger). The
aim of this project is to increase the protonic
conductivity of polymer membranes, usually used
in PEMFC, by hybridizing good proton conducting
glasses. The addition can be done by simple
impregnation of the membranes using the sol-gel
process. The membranes must have both good
mechanical and electrochemical properties at an
operating temperature greater than 120 ºC.
The advantage of the hybrids is the presence of
water which can increase the protonic mobility
and the higher temperature capability.
SOFCs are presently under development for
power generation. These devices are capable of
providing 250kW distributed power plants. The
principle can be used for generation of
electrical energy or concentration of oxygen. In
the second case, a current is imposed between the
electrodes and
pure oxygen (99) is collected on the anodic
side. Oxygen generators can be used for medical
purposes, as well as in defense technology. In
this new device, each part (cathode, anode and
electrolyte) is made through the sol-gel process.
- This method leads to interconnected layers all
the surface at the interface is used for the
electrochemical reaction. - The layers are very
thin, which allows miniaturization. - The sol-gel
process permits preparation of the
electrochemical device in different geometries.
The oxide used at the cathode is
La1-xSrxMnO3. The anode is either
La1-xSrxMnO3 (oxygen generator application) or a
cermet nickel-stabilized zirconia (fuel cell
application). The electrolyte material is
usually yttria stabilized zirconia.
Rutgers Sol-Gel Group
NEW MATERIALS USED AS ANODES IN LITHIUM ION
BATTERIES Nathalie Pereira, Ph.D. npereira_at_telcord
ia.com
http//www.rci.rutgers.edu/solgel/solgel.htm
Dr. Lisa Klein, Director licklein_at_rci.rutgers.edu
The goal is to get high energy density
batteries with good cyclability. However, the
growth of dendrites associated with the use of
metallic lithium increases the probability of
internal shorting. This safety problem prevents
metallic lithium use in commercial lithium ion
batteries. As a consequence, a search for
alternative materials to metallic lithium is
needed.

• Inorganic glasses have been studied to a vast
  extent for optical applications(integrated
  optics, optical sensors etc.,). Another class of
  materials called the "organic/inorganic hybrids"
  has been of interest in the last few years, for
  similar applications. This is because these
  materials allow us to draw from the advantages of
  both thesematerials. For instance, it is
  possible to
• form macropore-free films at lower temperatures,
• tailor the refractive index
• achieve good optical clarity (due to the
  inorganic matrix)
•   The focus of this research effort is to
  synthesize low-loss planar waveguides based on
  these hybrids, through the Sol-gel route.
  Sol-gel, being a low temperature processing route
  has several advantages over other techniques,
  particularly for introduction of the organics.
  The project is in its nascent stage still and the
  materials systems we are looking at are SiO2-TiO2
  and SiO2-Y2O3
•   As a second step, introduction of organics into
  these inorganic matrices will be taken up.  More
  information on the actual synthesis of the active
  and passive planar waveguides will be posted as
  the project progresses.

The lives of titanium electrodes used in
industrial applications are limited due to their
daily exposure to harsh conditions. The current
research is focusing on the effects of a diamond
layer, coated between the Ti surface and the
platinum top layer, on the lifetime of the
sample. The platinum top layer is plated to
the same thickness on both a control electrode
and a diamond interlayer electrode using a bath.
This top layer protects the Ti electrode from
exposure to acid. These electrodes are then
simultaneously tested in acid by running a
current through the system. It is believed that
the diamond interlayer will extend the life
expectancy of the electrode when compared to the
plain Pt plated Ti sample.
Carbonaceous materials are currently used in
commercial batteries but the SEI layer formation
at the surface of the grains is responsible for
an irreversible capacity loss and a capacity
fade. Therefore our attention has been focused on
silicon and tin.
)
The large volumetric changes resulting from
the alloying reaction with lithium while cycling
are responsible for poor cyclability. Our study
has then been extended to silicides and
nanoparticles of tin and tin oxides.

Voltage (Li/Li
Sn/Li
Sn
2
5
LiSn/Li
Sn
Li
Sn
/LiSn
"Li
Sn
"
7
3
2
5
22
5
Capacity (mAh/g)
Sn voltage profile