Doping-Induced Pre-Transformation to Extend Solid-Solution Regimes in Li-Ion Batteries
Doping-Induced Pre-Transformation to Extend Solid-Solution Regimes in Li-Ion Batteries.
Schofield P, Luo Y, Zhang D, Zaheer W, Santos D, Agbeworvi G, Ponis JD, Handy JV, Andrews JL, Braham EJ, Renuka Balakrishna A, Banerjee S.
ACS Energy Letters 7, 3286-92. (2022)
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Synopsis

We dope a phase-transforming V2O5 electrode to reduce structural distortions during charge/discharge processes.

Crystallographic design of intercalation materials
Crystallographic design of intercalation materials.
Renuka Balakrishna A.
Journal of Electrochemical Energy Conversion and Storage 19(4), 040802. (2022)
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Synopsis

We review how the structural transformation of lattices, phase transformation microstructures, and crystallographic defects affect the chemo-mechanical properties of intercalation materials.

Compatible microstructures in magnetic materials
Compatible microstructures in magnetic materials.
Renuka Balakrishna A.
Physical Review Materials 6, 074402. (2022)
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Synopsis

We propose a mathematical relationship between magnetic material constants for which highly reversible microstructures form during phase transformations.

Designing shape-memory-like microstructures in intercalation materials
Designing shape-memory-like microstructures in intercalation materials.
Zhang D, Renuka Balakrishna A.
arXiv preprint arxiv: 2206.14948. (2022)
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Synopsis

We develop a theoretical framework to predict structural transformations in intercalation compounds and establish crystallographic design rules necessary for forming shape-memory-like microstructures in intercalation materials.

Design of soft magnetic materials
Design of soft magnetic materials.
Renuka Balakrishna A, James RD.
NPJ Computational Materials 8(4), 1-10. (2022)
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Synopsis

We quantitatively demonstrate that the delicate balance between magnetocrystalline anisotropy, magnetostriction constants, and the spike-domain microstructure (localized disturbance) is necessary to lower magnetic coercivity.

Film strains enhance the reversible cycling of intercalation electrodes
Film strains enhance the reversible cycling of intercalation electrodes.
Zhang D, Sheth J, Sheldon, BW, Renuka Balakrishna A.
Journal of the Mechanics and Physics of Solids 155, 104551. (2021)
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Synopsis

We demonstrate how film straining of intercalation electrodes can circumvent its structural degradation upon repeated cycling.

A solution to the permalloy problem—A micromagnetic analysis with magnetostriction
A solution to the permalloy problem—A micromagnetic analysis with magnetostriction.
Renuka Balakrishna A, James RD.
Applied Physics Letters 118(21), 212404. (2021)
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Synopsis

We propose a solution to the longstanding “Permalloy problem”, i.e., why the particular composition of Fe21.5Ni78.5 achieves a dramatic drop in magnetic hysteresis.

A tool to predict coercivity in magnetic materials
A tool to predict coercivity in magnetic materials.
Renuka Balakrishna A, James RD.
Acta Materialia 116697. (2021)
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Synopsis

We develop a novel coericity tool that for the fist time combines micromagnetics with magnetostriction and non-linear stability analysis.

Phase-field model for diffusion-induced grain boundary migration: An application to battery electrodes
Phase-field model for diffusion-induced grain boundary migration: An application to battery electrodes.
Renuka Balakrishna A, Chiang YM, Carter WC.
Physical Review Materials 3(6), 065404. (2019)
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Synopsis

We use our previously developed multiscale phase-field framework to model electrode microstructures not only as a function of Li composition, but also predict the crystallographic features of the underlying electrode during battery operation.

Order-disorder transition in nano-rutile TiO2 anodes: A high capacity low-volume change Li-ion battery material
Order-disorder transition in nano-rutile TiO2 anodes: A high capacity low-volume change Li-ion battery material.
Christensen CK, Mamakhel A, Renuka Balakrishna A, Iversen BB, Chiang YM, Ravnsbæk D.
Nanoscale 11, 12347-12357. (2019)
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Synopsis

Using ex situ and operando scattering techniques we elucidate the phase transformation in LixTiO2 during repeated charge-discharge processes.

Mechanical instability of electrode-electrolyte interfaces in solid-state batteries
Mechanical instability of electrode-electrolyte interfaces in solid-state batteries.
Bucci G, Talamini B, Renuka Balakrishna A, Chiang YM, Carter WC.
Physical Review Materials 2(10), 105407. (2018)
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Synopsis

We use the cohesive-energy approach to analyze the delamination criterion and derive a stability condition
for fracture propagation at electrode-electrolyte interfaces in solid-state batteries.

Periodic boundary conditions for the simulation of 3D domain patterns in tetragonal ferroelectric material
Periodic boundary conditions for the simulation of 3D domain patterns in tetragonal ferroelectric material.
Muench I, Renuka Balakrishna A, Huber JE.
Archive of Applied Mechanics 89(6), 955-972. (2018)
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Synopsis

We identify the boundary conditions necessary to stabilize 3D domain patterns with long, ribbon-like domains threaded through them and with vortex-like features.

Combining phase-field crystal methods with a Cahn-Hilliard model for binary alloys
Combining phase-field crystal methods with a Cahn-Hilliard model for binary alloys.
Renuka Balakrishna A, Carter WC.
Physical Review E 97(4), 043304. (2018)
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Synopsis

We introduce, for the first time, a theoretical framework that combines a Cahn-Hilliard and a phase-field crystal model to describe a phase transition process.

Nanoscale domain patterns and a concept for an energy harvester
Nanoscale domain patterns and a concept for an energy harvester.
Renuka Balakrishna A, Huber JE.
Smart Materials and Structures 25(10), 104001. (2016)
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Synopsis

We find that simple domain patterns with stripe-like features are stable across a wide range of externally imposed strains, and explore its application in a thin film energy harvester.

Nanoscale periodic domain patterns in tetragonal ferroelectrics: A phase-field study
Nanoscale periodic domain patterns in tetragonal ferroelectrics: A phase-field study.
Renuka Balakrishna A, Huber JE, Muench I.
Physical Review B 93(17), 174120. (2016)
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Synopsis

We investigate the stability and evolution of periodic domain patterns in the form of multirank laminates in ferroelectrics. In contrast to previous findings using a linear, constrained theory, we find that these laminates are unstable at the nanoscale because of significant domain-wall energy.

Study of Periodic Domain Patterns in Tetragonal Ferroelectrics Using Phase-Field Methods
Study of Periodic Domain Patterns in Tetragonal Ferroelectrics Using Phase-Field Methods.
Renuka Balakrishna A, Muench I, Huber JE.
ASME 2015 Conference on Smart Materials, Adaptive Structures and Intelligent Systems SMASIS2015-8823, V001T02A001. (2016)
DOI

Scale effects and the formation of polarization vortices in tetragonal ferroelectrics
Scale effects and the formation of polarization vortices in tetragonal ferroelectrics.
Renuka Balakrishna A, Huber JE.
Applied Physics Letters 106(9), 092906. (2015)
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Synopsis

We provide a fundamental insight into the absence of experimental observation of classic polarization vortices of the form described by Kittel. Using phase-field calculations, we show that scale and surface conditions greatly affects the stability of polarization vortices making them energetically unfavorable at the fine scale.

Nano-actuator concepts based on ferroelectric switching
Nano-actuator concepts based on ferroelectric switching.
Renuka Balakrishna A, Huber JE, Landis CM.
Smart Materials and Structures 23(8), 085016. (2014)
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Synopsis

We present a novel actuation mechanism based on the collective and coordinated switching of ferroelectric domains. The strains resulting from this actuation are several times larger than piezoelectric strains alone, and we exploit this concept to design two nanoscale actuators.

Design optimization of a ferroelectric nano-actuator using phase-field modeling
Design optimization of a ferroelectric nano-actuator using phase-field modeling.
Renuka Balakrishna A, Huber JE.
MRS Online Proceedings Library Archive 1674. (2014)
DOI