In anode-free designs, a lithium-rich cathode is attached to a metal current collector directly. When the battery is charged, active lithium ions are released from the cathode and deposited onto the metal current collector, which acts as a temporary anode. We are focusing on improving the plating/stripping efficiency. Stay tuned for more updates .

In the traditional battery operation, a considerable amount of Li+ ions are lost during the first charge, which is attributed to the formation of a solid electrolyte interface (SEI) which is unfortunately irreversible. This irreversible Li+ ion can vary from 10-50 % in the case of intercalation (graphite) and alloying (Si/Ge/Sn) based material. The formation of SEI results in low initial coulombic efficiency and lower energy density while constructing the full cell. To overcome these issues, one of the significant attempts is to use the pre-lithiated anode to compensate for the initial Li loss during the initial SEI formation and form a stable SEI for better columbic efficiency and to attain high energy density. To overcome these drawbacks, researchers need to find an alternative synthesis approach to obtain an air-stable pre-lithium additive that can be directly used during the electrode preparation. Thus, the development of the large-scale synthesis of pre-lithiation additives has been critical for the next-generation lithium-ion battery with high energy density.

Related Publications:

Pranav Kulkarni, Hyun Young Jung, Debasis Ghosh, Mohammed Jalalah, Mabkhoot Alsaiari, Farid A.Harraz, R. Geetha Balakrishna, A comprehensive review of pre-lithiation/sodiation additives for Li-ion and Na-ion batteries, Journal of Energy Chemistry, 76,  2023, Pages 479-494.

Zinc-ion chemistry has been extensively explored due to its abundance, high volumetric capacity (5855 mAh/cm3) and gravimetric capacity (820 mAh/g), and low reduction potential (−0.76 V vs. SHE) since the first demonstration of Zn-ion batteries (ZIBs) using Zn/MnO2 in mild electrolytes (ZnSO4). Despite significant efforts in engineering the Mn-based cathodes to improve their electrochemical performance, the current state-of-the-art Zn-ion batteries are far from successful commercialization because they still suffer from rapid degradation during cycling due to limited ion transport and uncontrolled Mn dissolution. Recently, the alternative to Mn-based materials, the open framework structure of vanadium-based compounds, has attracted interest due to many advantages such as thermal stability, fire resistance, high specific capacity, multiple redox reactions, and large interlayer spacing. Although vanadium-based compounds have benefits as potential cathodes, they are still plagued by a critical issue, which involves the dissolution of vanadium in an aqueous system and the formation of Zinc based salts (Zn4SO4(OH)6·xH2O) at the interface that causes a significant effect on the long-term cycling. 

• Pre-intercalation of the cathodes has been considered one of the most efficient strategies to enhance the reversible Zn2+ insertion/de-insertion kinetics by improving the interplanar spacing. 

• Artificial interface to suppress the vanadium dissolution in vanadium cathodes 

• Extending the electrochemical window using water-in-salt, water-in-bisalt, water-in-ionomer, hybrid aqueous/non-aqueous, and hydrate-melt electrolytes

• Surface modification of anodes to achieve dendrite-free deposition 

Related Publications:

Pranav Kulkarni, Sun-Sik Kim and Hyunyoung Jung, Chemical Surface Tuning of Zinc Metal Anode Toward Stable, Dendrite-less Aqueous Zinc-ion Batteries, Submitted, Journal of Energy Chemistry.

Pranav Kulkarni, and Hyunyoung Jung, In situ construction of barium-induced cathode electrolyte interphase to enable thermostable high-performance zinc-ion batteries, Materials Today Energy. 32, 2023, 101254. 

Pranav Kulkarni, Hemanth Kumar Beere, Mohammed Jalalah, Mabkhoot Alsaiari, R. Geetha Balakrishna, Farid A. Harrazb, and Debasis Ghosh Developing a high-performance aqueous zinc battery with Zn2+ pre-intercalated V3O7.H2O cathode coupled with surface engineered metallic zinc anode, Journal of Electroanalytical Chemistry, 924, 2022, 116851.

Pranav Kulkarni, D Ghosh, G Balakrishna, Recent Progress in ‘Water-in-Salt’ and ‘Water-in-Salt’- Hybrid Electrolytes Based High Voltage Rechargeable Batteries, Sustainable Energy Fuels, 2021, Advance Article, 5 (6), 1619-1654.

Puttaswamy, Rangaswamy*; Nagaraj, Radha*; Pranav Kulkarni; Beere, Hemanth; Upadhyay, Shrish; Balakrishna, R. Geetha; Sanna Kotrappanavar, Nataraj; Pakhira, Srimanta; Ghosh, Debasis, "Constructing a High-Performance Aqueous Rechargeable Zinc-ion Battery Cathode with Self-assembled Mat-like Packing of Intertwined Ag(I) Pre-inserted V3O7.H2O Microbelts with Reduced Graphene Oxide Core", ACS Sustainable Chemistry & Engineering, 2021, 9 (11), 3985-3995. 

Graphite has been one of the well-established intercalation anode materials for lithium-ion batteries with a theoretical capacity of 372 mAh g-1. The low working potential of 0.1 V vs. Li/Li+ results in the decomposition of electrolytes and forming of a solid electrolyte interface (SEI) which results in a large irreversible capacity. Another disadvantage of graphite is that at a higher current density, there is a risk of dendrite or lithium plating formation. Thus, researchers have been looking for an alternative material with a higher operating voltage. TiO2 and Li4Ti5O12 have been extensively studied as alternative anode materials with a theoretical capacity of 168 mAh g-1 and 175 mAh g-1, respectively. Past few years, a new class of high niobium-content anode materials has caught the attention of researchers due to their exceptional structural stability. 

Related Publications:

Pranav Kulkarni, Chung-Hsin Lu, S. Balaji, and P.Senthil Kumar, Exploration of electrochemical and lithium transport properties of BaNb3.6O10 as an anode material for lithium-ion batteries, Journal of alloys and compounds, Volume 830, 25 July 2020, 154306. 

In the last few decades, metal oxides have been widely employed for various applications such as gas sensors, oxygen reduction reactions, hydrogen generation, supercapacitors, lithium-ion batteries, solar cells, optoelectronic devices, etc. Nano-structuring of these metal oxides has shown unusual mechanical, electrical, and optical properties, which have gained importance in various applications. Nano-engineering of electrode materials has proven to enhance the electrochemical performances of LIBs. Moving from conventional bulk to nanostructures offers several advantages for LIBs, including (i) an increase in electrode/electrolyte contact area that permits higher lithium-ions across the interface for LIBs and a large number of ion adsorption sites for double-layer formation and charge-transfer reactions for SCs, (ii) shorter path lengths for ionic/electronic transport with faster diffusion rates, (iii) better accommodation of the mechanical strain and structural distortion generated from ion insertion/extraction and other reactions, and (iv) occurrence of new reactions that are not possible with bulk materials. We have explored various binary metal oxides and their carbon composites as potential anode materials for lithium-ion batteries. 

Related Publications:

Pranav Kulkarni, N. Sanna Kotrappanavar, R. Geetha Balakrishna, D. H. Nagaraju, and M. V. Reddy, Nanostructured binary and ternary metal sulfides: synthesis methods and their application in energy conversion and storage devices, J. Mater. Chem. A, 2017, 5, 22040-22094

Pranav Kulkarni, Debasis Ghosh, R.Geetha Balakrishna, RS Rawat, S Adams, MV Reddy, Investigation of MnCo2O4/MWCNT composite as anode material for lithium-ion battery, Ceramics International, 2019. 45 (8), 10619-10625.

Pranav Kulkarni, Debasis Ghosh, R. Geetha Balakrishna, R.S. Rawat, M.V. Reddy and Stefan Adams, Facile high yield synthesis of MgCo2O4 and investigation of its role as anode material for lithium-ion batteries Ceramics International, 2019 45 (12), 14775-14782. 

Pranav Kulkarni, Chepurthy Varnika, Beverly Low Ying Tong, Debasis Ghosh, R. Geetha Balakrishna, R.S.Rawat,  S.Adams, M.V.Reddy, Investigating the role of precipitating agents on the electrochemical performance of MgCo2O4, Journal of electroanalytical Chemistry, 851, 2019, 113403.

Pranav Kulkarni, R. Geetha Balkrishna, Debasis Ghosh, R.S.Rawat, Rohit Medwal, B.V.R. Chowdari, Zaghib Karim, M.V.Reddy, Molten salt synthesis of CoFe2O4 and its energy storage properties, Materials Chemistry, and Physics,  257, 2021, 123747.

P Nithyadharseni, KP Abhilash, Shaikshavali Petnikota, MR Anilkumar, Rajan Jose, KI Ozoemena, R Vijayaraghavan, Pranav Kulkarni, R. Geetha Balakrishna, BVR Chowdari, Stefan Adams, MV Reddy, Synthesis and lithium storage properties of Zn, Co, and Mg-doped SnO2 nanomaterials, Electrochimica Acta,  247, 2017, 358-370.