Research Interests

Introduction

My core area of studies has been related to the Metallurgical and Materials Engineering. As part of the Undergraduate programme at IIT Kharagpur, I was exposed to subjects such as Mechanical Metallurgy, Transport Phenomena, Thermodynamics of Materials etc. Simultaneously, I was pursuing a Masters Degree on Engineering Entrepreneurship at Rajendra Mishra School of Engineering Entrepreneurship, IIT Kharagpur. As a part of this programme, I expanded my knowledge to fields such as Product Development, Marketing and Market Research, Engineering Process Design, Management of Growth Ventures etc. I decided to pursue my Doctoral studies immediately without any academic gap at IIT Kharagpur, where I am working on developing new material chemistry for lithium and sodium-ion batteries.

Current Projects and Research Objectives

As a part of Doctoral studies, I am currently working on investigating new material chemistry as cathode materials for Lithium and Sodium-Ion batteries. I chose not to investigate the traditional materials such as LiFePO₄, LiCoO₂, NMC, NCA etc. directly, and instead focused on experimentally exploring some non-traditional structures which may exhibit some interesting properties in LIB and SIB. The whole problem statement is open and diverse, with high risk of failures. The designed materials may or may not be accepted by the scientific community. Yet, such a problem statement has been chosen since it allows for a wide range of techniques and ideas to be implemented on relatively unknown battery materials. Some of the concepts which have been designed for such materials can also be implemented to conventional battery systems to improve their performance.

• Phase 1: Investigation of amorphous forms of naturally occurring minerals (Alkali metal-ion deficient) as potential cathode materials in LIB and SIB

• Phase 2: Investigation of naturally occurring minerals (Alkali metal-ion deficient) as potential cathode materials in LIB, which can provide high specific capacity due to presence of multi-electron redox couples.

• Phase 3: Implementation of the developed strategies in Phase 1 and 2 to improve the electrochemical performance of the conventional battery systems

Phase 1: Development of amorphous sodium iron carbonophosphate as cathode materials for Lithium and Sodium-ion batteries

Based on the idea of a naturally occuring class of minerals known as Sidorenkite (Na_xYPO_4­CO₃), where Y = Mn, Fe, Co etc., Gerbrand Ceder and co. demonstrated computationally and experimentally the viable use of such class of materials as cathodes for sodium-ion batteries. Drawing inspiration from this work, it was envisioned in our group that amorphization of these materials can done by changing the oxidation state of the transition metal ion during the synthesis. Amorphous sodium iron carbonophosphate was synthesized by using a cost-efficient and green microwave assisted hydrothermal synthesis process by tweaking the recipe for artificially synthesizing the sidorenkite class of materials. The most astonishing feature which is observed in this material is that the charge-discharge profile resembles very closely to the EDLC type supercapacitor materials. A new mechanism of percolation based non-reductive insertion of lithium ions is proposed based on the studies on this material.

Performance wise, the material can charge to ~85% of its capacity in about 7 min. On comparing the performance of the material with reported supercapacior materials, it is found that the performance is superior when projected as a Li-ion capacitor cathode material.

Ref: Mitra, Arijit, Sambedan Jena, Subhasish B. Majumder, and Siddhartha Das. "Supercapacitor like behavior in nano-sized, amorphous mixed poly-anion cathode materials for high power density lithium and other alkali-metal ion batteries." Electrochimica Acta 338 (2020): 135899.

Phase 2: Investigation of naturally occurring minerals (Alkali metal-ion deficient) as potential cathode materials in LIB, which can provide high specific capacity due to presence of multi-electron redox couples.

Naturally occuring minerals provide a great template to develop new battery materials, as demonstrated in Phase 1 of the work and also by other research groups. In this phase, a vanadium based naturally occuring mineral is envisioned with the target of improving the energy density through increase in specific capacity. For this study, a naturally occuring mineral by the name of Kazakhstanite (Fe₅V₁₅O₃₉(OH)₉.9H₂O) is studied for its use as LIB cathode material. This phase can be synthesized by simple wet chemical process without the use of any complicated machinery or equipment. Due to the presence of multi-electron vanadium redox couple, this phase delivers a high specific capacity of ~300-350mAhg^-1 between 1.5-3.8V, making its energy density higher than LMO, NMC and comparable to NCA and OLO's. However, we observed that this phase has very poor cycleability whose cause is identified to be active material dissolution through systematic studies. A strategy to improve its cycleability has been further developed and studied, which drastically improves the performance of this phase, and vanadium containing cathode materials as a further extension

Ref:

1. Mitra, Arijit, Advait Gilankar, Sambedan Jena, Debasish Das, Subhasish B. Majumder, and Siddhartha Das. "Investigations on the improved cycling stability of Kazakhstanite phase Fe-VO layered oxide by using superconcentrated electrolytes: Generalized solubility limit approach (Part I)." arXiv preprint arXiv:2111.14198 (2021).

2. Mitra, Arijit, Saptarshi Das, Debasish Das, Subhasish B. Majumder, and Siddhartha Das. "Effect of salt concentration on the solubility, ion-dynamics, and transport properties of dissolved vanadium ions in lithium-ion battery electrolytes: Generalized solubility limit approach (Part II)." arXiv preprint arXiv:2111.14591 (2021).