Multiferroic-Centric Materials and Systems Engineering for Battery Applications: An Insight Into Mechanisms, Strategies, and Characterizations.

Ferroic order parameters constitute field-addressable internal thermodynamic variables that can be switched and coupled to reshape the electrochemical boundary conditions governing batteries. Conventional approaches to engineer battery materials, such as doping, coating, defect, and entropy engineering, primarily alter chemistry and microstructure, and are often static after fabrication. Whereas multiferroicity regulation can act as a complementary design principle that offers internal biases, spin polarization, and reconfigurable strain that dynamically address critical challenges, such as space-charge formation, sluggish charge-transfer kinetics, interphase evolution, and dendrite-assisted failure, found in battery systems. This review dissects ferroic-driven electrochemical performance enhancements from the cell level down to individual components and buried interfaces, establishing a mechanistic framework that correlates single- and coupled-ferroic responses to measurable electrochemical descriptors. Beyond mechanistic analysis, we assess strategies such as material architecture design and field engineering that enable deterministic control of targeted ferroic orders across diverse battery chemistries. Further, we consolidate ferroic-resolved characterizations, including advanced magnetometry, spectroscopic and microscopic techniques, as well as the emerging operando and in situ setups that are critical to battery systems. Overall, this work bridges ferroic-mediated electrochemistry and multiferroic-centric battery engineering, enabling next-generation battery systems in which ferroic order parameters operate as dynamic, operando-addressable state variables under realistic cycling conditions.