Energy Systems


Energy Systems


Development of membrane electrode assemblies for tubular fuel cells by Amit C. Bhosale


Well, it all starts and ends with the heart be it living things or fuel cells! The membrane electrode assembly that is considered as the heart of the cell needs to be prepared with utmost attention and care! The planer fuel cells have been conventionally used with their MEAs optimized over time. However, the electrodes seem to have been delaminated when such MEAs are wrapped around in case of tubular fuel cells! This increases the ohmic drop in terms of potential multifold.

Proposed design of tubular fuel cell

Moreover, maintaining optimized contact pressure between the tubes and MEA yet restricting gas to leak is a challenge. We, therefore, at IIT Madras, are trying to optimize the MEA as well as new design for air breathing tubular fuel cells. A catalyst coated membrane (CCM) is being tried out with more efforts on optimization of ionomer content so that electrodes do not delaminate.
Another extension is to develop new designs of the cell including the flow patterns for the hydrogen for better distribution and usage.

List of Publications:

A sample of MEA prepared in the laboratory

  • Bhosale et al., Modeling and experimental validation of a unitized regenerative fuel cell in electrolysis mode of operation, Energy, 121, 2017, 256–263.
  • Bhosale et al., Root cause analysis of the degradation in a unitized regenerative fuel cell, Journal of Power Sources, 343, 2017, 275–283.

*Adapted from the work carried out by Dr Amit C B during his PhD, in Prof Prakash Ghosh’s lab in IIT Bombay, India


Modeling, Simulation and Performance Enhancement of All-Vanadium Redox Flow Battery by Deepa Elizabeth Eapen


VRFB is an electrochemical storage system which stores energy in its electrolytes. The design allows easy scalability, modularity and design flexibility. The system can be recharged or refuelled. However, owing to low energy density, the system sizes are very large and are presently implemented for large scale storages. At SENAI, attempts are made to study the physical and electrochemical phenomena involved, through modelling and experimentation. Various methods of augmenting the VRFB performance are investigated. Few of these include operation at high temperature to achieve low grade thermal energy capture, steady state operation for constant potential output, and network design for multiple stacks.

 

List of Publications:

  • Eapen, Deepa Elizabeth, and Raghunathan Rengaswamy. “A systems engineering framework for applicationdependent identification and design of electrochemical energy conversion systems.” Computer Aided Chemical Engineering. Vol. 40. Elsevier, 2017. 2587-2592.
  • Eapen, Deepa Elizabeth, Suman R. Choudhury, and Raghunathan Rengaswamy. “Low grade heat recovery for power generation through electrochemical route-Vanadium Redox Flow Battery, a case study.” Applied Surface Science(2018).
  • Deepa E. Eapen, S.R. Suseendiran, R. Rengaswamy, “Phosphoric acid fuel cells”, Chapter 2, Compendium of hydrogen energy, Volume 3: Hydrogen energy conversion, Woodhead Publishing, 2015.

 


 Prognosis and Management of Lithium Ion Batteries by Sathish Swaminathan


Lithium ion batteries are in high demand as energy storage devices, especially for portable and automotive applications. Their popularity can be attributed to their high energy densities, scalability, long life and reducing costs. However, lithium ion batteries are beset with issues that need to be addressed. They have finite life and are subject to performance and capacity degradation which are irreversible. Unwarranted capacity loss is a major cause of concern for battery and electric vehicle manufacturers which necessitates the need for battery prognostics. Conventional prognostic techniques are time intensive and require sophisticated equipment. In addition, lithium ion batteries are highly sensitive to variations in operating conditions and are susceptible to safety hazards. There is a need to manage and operate batteries under optimal conditions in order to ensure, performance, safety and longevity.

Battery research at SENAI focusses on applying systems engineering principles to identify quicker and effective prognostic techniques that could assist development in battery technology; developing novel diagnostic tools for batteries; conceive designs and control strategies for state of the art battery management systems.

List of publications

  • S. Raman, S. Swaminathan, S. Bhardwaj, H.K. Tanneru, B. Bullecks, R. Rengaswamy, Rapid humidity regulation by mixing of dry and humid gases with feedback control for PEM fuel cells, Int. J. Hydrogen Energy. (2018). doi:10.1016/j.ijhydene.2018.04.187.

Discovering novel electrolytes for flow battery by Sivadurgaprasad Chinta


Flow batteries are energy storage devices, which store electrical energy in the form of chemical energy and converts it back to electrical energy when needed. The major advantage of flow batteries is energy power decoupling. The hurdle for flow battery commercialization is their low energy densities. Energy densities can be improved by increasing the solubility of current electrolytes or by discovering novel electrolytes with high reduction potential values. To increase the solubility values of currently used electrolytes different solvent systems can be explored.  To discover novel electrolyte chemistries both experimental and computational studies can be used. Experimental synthesization of electrolytes are cost and time demanding. Computational studies of discovering novel molecules for any objective involves two phases. First, calculating the values of deciding factors (of chosen objective) for targeted range of molecules. Second, selecting suitable molecules using a backward optimization. In the case of discovering novel electrolytes, reduction potential and aqueous solubility can be selected as deciding factors. To calculate these values for accessible ‘Quinone’ derivatives within reasonable time, identifying the QSPRs (Quantitative structure property relationships) is a potential remedy. To improve solubility, first we try to identify a generalized solubility relationship from the structural information of solute and both solvents of the solubility data available (drug solubility data of 63 binary systems at various temperatures and compositions).

List of publications:

  • Chinta Sivadurgaprasad, Abhishek Sivaram and Raghunathan Rengaswamy, “Prediction error based clustering approach for multiple-model learning using statistical testing”, Submitted revision, Engineering Applications of Artificial Intelligence.

 Development of Cylindrical PEM Fuel Cells by S.R. Suseendiran.


PEM Fuel Cells (PEMFC) are attractive because of advantages such as low-temperature operation, no emission of harmful gases and high efficiency. However, the bipolar plates used in the state of the art planar architecture is costly and increases the dead weight of the cell. In addition, the flow channels in the planar fuel cell increase the difficulty in removing the water produced in the cathode during cell operation. Cylindrical PEM fuel cells, on the other hand, do not require bipolar plates and also there is no need for precisely machined flow channels. Thus, cylindrical PEM fuel cells are cheap, efficient in water management, and possess higher volumetric and gravimetric power density compared to planar PEM fuel cells. The design of cylindrical fuel cell is very simple, but the fabrication of the same is fairly complex. Prevention of hydrogen leak and increasing the MEA compression are few such difficulties faced during the fabrication of cylindrical PEM fuel cells. Our team mainly focusses on the development of cylindrical PEM fuel cell and stack prototypes, prototype diagnostics and design optimization.

List of Publications:

  • S.R. Suseendiran, S. Pearn-Rowe, and R. Rengaswamy, “Strategies for Effective Utilization of Hydrogen in Cylindrical PEM Fuel Cells”, ECS Transactions, vol. 80, no. 8, pp. 485-496, 2017.