Magnetism mediated flexible battery bridging soft robotics and  flexible electronics 

Changsheng Wu¹,* 

¹Department of Materials Science and Engineering, National University of Singapore, Singapore E-mail: cwu@nus.edu.sg 

Abstract

Recent breakthroughs in flexible electronics and soft robotics unveil a blueprint for creating  autonomous soft intelligent machines. However, the integration of flexible onboard power  sources becomes imperative to support the untethered functionality and advanced electronic  functionalities, such as sensing, computation, and communication. An optimal battery for soft robots and flexible electronics must withstand substantial  deformations. Flexible zinc batteries, boasting enhanced safety and environmental friendliness in  comparison to commonly used lithium batteries, emerge as an attractive power solution for  wearables and implantables. However, challenges such as dendrite formation on the zinc anode  and the Jahn-Teller effect in the cathode pose significant hurdles, impacting the performance and  cycle life of zinc batteries. Frequent deformations in soft robotics applications exacerbate these  challenges. Hence, the development of deformation-resilient flexible batteries necessitates  strategic approaches to address aforementioned challenges while preserving the deformation  capability of soft robots and flexible electronics. In this talk, I will introduce our recent research on utilizing magnetic field to enhance the  durability and cyclability of flexible batteries. Through soft ferromagnetic encapsulation, we  investigated the effects of an internal magnetic field on both zinc metal anode and MnO2 cathode of a flexible Zn-MnO2 battery. Experimental results and theoretical modeling suggested that the magnetic remanence of ferromagnetic encapsulation helps suppress Zn dendrite growth and  Jahn-Teller distortion, addressing the key challenges of stable long-term operation of flexible  batteries in deformation-prone scenarios. We further demonstrated an intelligent manta ray fish  robot based on the magnetism mediated flexible battery. With onboard flexible battery to power  flexible electronic modules capable of motion sensing and wireless communication, the robotic manipulation through an electromagnetic coil array could adapt to external perturbations and  real-time feedback control of the fish robot was realized.