Emerging Design Strategies Toward Developing Next‐Generation Implantable Batteries and Supercapacitors

Abstract

In recent years, the development of implantable bioelectronics has garnered significant attention. With the continuous advancement of IoT and information technology, implantable bioelectronics can be utilized more effectively for health monitoring to enhance treatment outcomes, reduce healthcare costs, and improve quality of life. Implantable energy storage devices have been widely studied as critical components for energy supply. Conventional power sources are bulky, inflexible, and potentially contain materials that are dangerous to the body. Meanwhile, human tissues are soft, flexible, dynamic, and closed, which puts new requirements on energy storage devices to improve the safety, stability, and matching of implantable batteries or supercapacitors. Herein, recent advances in state‐of‐the‐art nonconventional power options for implantable electronics, specifically biocompatible, miniaturized, stretchable/deformable, biodegradable/bioresorbable, edible, and injectable energy storage devices, are reviewed in this paper. The material strategy and architectural design of the next‐generation implantable energy storage device are discussed, including the selection principle of electrolytes, the all‐in‐one structure design strategy, and the way to realize self‐charging. Finally, the challenges and prospects of emerging design strategies toward developing next‐generation implantable batteries and supercapacitors for the future are put forward.

Perspectives on recent advancements in energy harvesting, sensing and bio-medical applications of piezoelectric gels

“…The usage of batteries can be challenging due to recycling and replacement issues as well as their short lifespan. 385,386 The concept of self-powered devices has significant advantages for the utilization of renewable energy sources, such as wind, waves, mechanical vibrations, breathing, blood flow, and other human-body movements. 387,388 Among various self-powered technologies, the most attractive portable devices and intelligent systems are based on piezoelectric hydrogels due to their combination of light-weight, high sensitivity, outstanding exceptional flexibility, skin-like mechanical characteristics and outstanding electrical properties.…”

Sustainable stretchable batteries for next-generation wearables

“…19 This is more pertinent for next-generation wearables as miniaturisation is crucial for integration with the user, 20 especially for implantable devices where volumetric space is a limitation. 21–23…”

“…14–18 There are also several focused reviews ranging from structural engineering to enable stretchability, 34,35 battery systems such as aqueous, 26,27,36 metal–air, 37 nanowire, 38 and microbattery, 39 and application centred topics for skin-interfaced and implantable wearables. 21,22,29 Here, we will not delve into details of the various strategies as they have been previously covered in review articles. Instead, we will provide our perspective on the challenges facing the current stretchable battery technology, which are the mechanical and electrochemical performance (challenge I) and its sustainability and biocompatibility (challenge II), as illustrated in Fig.…”

Ultra-expanded interlayer spacing of vanadium oxide nanowires intercalated with poly(3,4-ethylene dioxythiophene) in organic ammonium ion batteries

“…It is well known that the properties of batteries are substantially defined by charge carriers. 1,2 The batteries employing ammonium (NH 4 + ) ions are promising and competitive energy candidates to meet low-cost application requirements owing to the merits of light molar mass (18 g mol −1 ) and abundant synthetic resources. 3,4 Compared with metal ions, NH 4 + ions can be synthesized from hydrogen and nitrogen, which are essentially abundant on earth.…”