Biomimetic Exogenous "Tissue Batteries" as Artificial Power Sources for Implantable Bioelectronic Devices Manufacturing

Abstract

Implantable bioelectronic devices (IBDs) have gained attention for their capacity to conformably detect physiological and pathological signals and further provide internal therapy. However, traditional power sources integrated into these IBDs possess intricate limitations such as bulkiness, rigidity, and biotoxicity. Recently, artificial "tissue batteries" (ATBs) have diffusely developed as artificial power sources for IBDs manufacturing, enabling comprehensive biological-activity monitoring, diagnosis, and therapy. ATBs are on-demand and designed to accommodate the soft and confining curved placement space of organisms, minimizing interface discrepancies, and providing ample power for clinical applications. This review presents the near-term advancements in ATBs, with a focus on their miniaturization, flexibility, biodegradability, and power density. Furthermore, it delves into material-screening, structural-design, and energy density across three distinct categories of TBs, distinguished by power supply strategies. These types encompass innovative energy storage devices (chemical batteries and supercapacitors), power conversion devices that harness power from human-body (biofuel cells, thermoelectric nanogenerators, bio-potential devices, piezoelectric harvesters, and triboelectric devices), and energy transfer devices that receive and utilize external energy (radiofrequency-ultrasound energy harvesters, ultrasound-induced energy harvesters, and photovoltaic devices). Ultimately, future challenges and prospects emphasize ATBs with the indispensability of bio-safety, flexibility, and high-volume energy density as crucial components in long-term implantable bioelectronic devices.

Keywords: artificial tissue batteries; implantable bioelectronic devices; implantable power sources.

Figure 1

Timeline of important milestones in the development of ATBs for IBDs. Energy storage devices,^{[ 17} , ¹⁸ , ¹⁹ , ²⁰ , ²¹ , ²² , ²³ , ²⁴ , ^{25 ]} internal power harvesters,^{[ 26} , ²⁷ , ²⁸ , ²⁹ , ³⁰ , ^{31 ]} and external wireless power transfer systems.^{[ 32} , ³³ , ³⁴ , ³⁵ , ³⁶ , ^{37 ]} (TEG: thermoelectric nanogenerator, PENG: piezoelectric nanogenerator, TENG: triboelectric nanogenerator, PENG: piezoelectric nanogenerator, RF: Radio‐frequency, APT: Acoustic power transfer, AWD: Auto watch device, PV: photovoltaic, UEH: Ultrasonic Energy Harvesters).

Figure 2

Schematic of functional units for diagnosis, closed‐loop, therapy of IBDs powered by ATBs. (ADC, Analog to Digital Converter; DAC, Digital to Analog Converter)

Figure 3

Chemical batteries. A) The power supply mechanism of chemical batteries. B) Liquid and solid batteries. Reproduced with permission.^{[ 185 ]} Copyright 2018, Springer Nature. Reproduced with permission.^{[ 186 ]} Copyright 2022, Elsevier. C) Primary and secondary batteries. Reproduced with permission.^{[ 206 ]} Copyright 2021, Wiley‐VCH. D) The structural designs of chemical batteries. Reproduced with permission.^{[ 213 ]} Copyright 2013, Springer Nature. Adapted with permission.^{[ 215 ]} Copyright 2015, Wiley‐VCH. Reproduced with permission.^{[ 216 ]} Copyright 2014, Springer Nature. E) Biocompatibility and biodegradation of chemical batteries. Reproduced with permission.^{[ 225 ]} Copyright 2019, Springer Nature. Reproduced with permission.^{[ 231 ]} Copyright 2015, Wiley‐VCH. Reproduced with permission.^{[ 223 ]} Adapted 2017, American Chemical Society.

Figure 4

Supercapacitors. A) The power supply mechanism and conventional materials of supercapacitors. B) Materials that stretch (MTS) for flexible supercapacitors. Reproduced with permission.^{[ 248 ]} Copyright 2021, Wiley‐VCH. C) structures that stretch for flexible supercapacitors. Reproduced with permission.^{[ 235 ]} Copyright 2017, Elsevier. Adapted with permission.^{[ 251 ]} Copyright 2017, Wiley‐VCH. Adapted with permission.^{[ 252 ]} Copyright 2015, Wiley‐VCH. D) Biocompatibility and biodegradability of supercapacitors. Reproduced with permission.^{[ 234 ]} Copyright 2017, Wiley‐VCH. Adapted with permission.^{[ 253 ]} Copyright 2013, Springer Nature. Adapted with permission.^{[ 257 ]} Copyright 2017, Wiley‐VCH. Reproduced with permission.^{[ 254 ]} Copyright 2023, Advanced Science.

Figure 5

Biofuel cells. A) The power supply mechanism of biofuel cells. B) Enzymes biofuel cells. Adapted with permission.^{[ 285 ]} Copyright 2013, Springer Nature. Reproduced with permission.^{[ 133 ]} Copyright 2021, Elsevier. Reproduced with permission.^{[ 286 ]} Copyright 2021, Wiley‐VCH. Reproduced with permission.^{[ 287 ]} Copyright 2013, Royal Society of Chemistry. C) Abiotic biofuel cells. Reproduced with permission.^{[ 298 ]} Copyright 2015, Royal Society of Chemistry. Reproduced with permission.^{[ 302 ]} Copyright 2015, Royal Society of Chemistry. Adapted with permission.^{[ 303 ]} Copyright 2020, Wiley‐VCH. Reproduced with permission.^{[ 304 ]} Copyright 2013, Springer Nature.

Figure 6

Thermoelectric Energy Harvesters (TEGs). A) The power supply mechanism of TEGs. B) Thermoelectric energy harvesting of human body heat for wearable sensors. Adapted with permission.^{[ 317 ]} Copyright 2022, Wiley‐VCH. C) TEGs based on Bi₂Te₃/Sb₂Te₃ p‐n Junctions. Reproduced with permission.^{[ 321 ]} Adapted 2021, Wiley‐VCH. D) THEs based on nano‐SiC dispersed NaCo₂O₄ composites. Reproduced with permission.^{[ 322 ]} Copyright 2019, World Scientific. E) TEGs based on conducting polymer (poly(3, 4‐ethylenedioxythiophene)). Reproduced with permission.^{[ 328 ]} Adapted 2011, Springer Nature. F) A gill‐mimicking thermoelectric generator based on polyaniline and multiwalled carbon nanotube. Reproduced with permission.^{[ 332 ]} Copyright 2021, Royal Society of Chemistry. G) an implantable thermal generator. Reproduced with permission.^{[ 337 ]} Copyright 2007, IOP Publishing.

Figure 7

Devices Utilize Biopotentials. A) Endocochlear potential. Adapted with permission.^{[ 30 ]} Copyright 2012, Springer Nature. B) An electric‐eel‐inspired soft power source from stacked hydrogels. Reproduced with permission.^{[ 342 ]} Copyright 2017, Springer Nature.

Figure 8

Piezoelectric nanogenerators (PENGs). A) The power supply mechanism of PENGs. B) Inorganic materials for PENGs. Adapted with permission.^{[ 356 ]} Copyright 2014, Wiley‐VCH. C) Organic and non‐biodegradable materials for PENGs. Adapted with permission.^{[ 362 ]} Copyright 2015, Elsevier. D) Organic and biodegradable materials for PENGs. Reproduced with permission.^{[ 385 ]} Copyright 2015, IEEE. E) Composite materials for PENGs. Adapted with permission.^{[ 388 ]} Copyright 2021, Elsevier. F) 3D piezoelectric microsystem of PENGs. Reproduced with permission.^{[ 392 ]} Copyright 2019, Springer Nature.

Figure 9

Triboelectric Energy Harvesters (TENGs). A) The power supply mechanism of TENGs. B) TENGs for treatment. Reproduced with permission.^{[ 404 ]} Copyright 2022, Elsevier. C) TENGs for detection. Adapted with permission.^{[ 407 ]} Copyright 2019, Wiley‐VCH. D) TENGs for never stimulation. Adapted with permission.^{[ 408 ]} Copyright 2018, Springer Nature. E) Biodegradable materials for TENGs. Reproduced with permission.^{[ 416 ]} Copyright 2018, Wiley‐VCH.

Figure 10

A) Electromagnetic spectrum. B) The power supply mechanism of WPT. C) Classification of electromagnetic waves according to their distance from the source. D) The penetration depth and attenuation level of RF waves with different frequencies in different human tissues. Reproduced with permission.^{[ 442 ]} Copyright 2016, Society for reproduction and fertility.

Figure 11

A) An implantable ionic wireless power near‐field transfer system (CC). Reproduced with permission.^{[ 447 ]} Copyright 2020, American Chemical Society. B) A miniaturized, battery‐free photofluid system based on IC with wireless pharmacology and optogenetics potential. Reproduced with permission.^{[ 448 ]} Copyright 2018, Wiley‐VCH. C) Wireless power transfer to deep‐tissue microimplants based on Mid‐field. Reproduced with permission.^{[ 48 ]} Copyright 2014, National Acad Sciences. D) A novel RF‐powered wireless pacemaker and a wearable transmit‐antenna array based on Far‐field WPT. Reproduced with permission.^{[ 453 ]} Copyright 2018, IEEE. E) Bioresorbable electronic stimulators. Reproduced with permission.^{[ 455 ]} Copyright 2020, Springer Nature.

Figure 12

Ultrasound‐induced energy harvesters (UEHs). A) The power supply mechanism of UEHs. B) The relationship between normalized power attenuation of sound waves and tissue depth and ultrasound frequency. Reproduced with permission.^{[ 470 ]} Copyright 2014, Elsevier. C) A miniature rigid neural stimulator with ultrasonically powered bidirectional communication. Reproduced with permission.^{[ 464 ]} Copyright 2020, Springer Nature. D) Ultrasound‐induced flexible wireless energy harvesting for potential retinal electrical stimulation application. Reproduced with permission.^{[ 137 ]} Copyright 2019, Wiley‐VCH. E) Flexible piezoelectric ultrasonic energy harvester array for bio‐implantable wireless generator. Reproduced with permission.^{[ 467 ]} Copyright 2019, Elsevier. F) Transcutaneous ultrasound energy harvesting using capacitive triboelectric technology. Reproduced with permission.^{[ 37 ]} Copyright 2019, Science. G) Transcutaneous ultrasound energy harvesting using TENGs. Reproduced with permission.^{[ 459 ]} Copyright 2022, Cell.

Figure 13

Photovoltaic Devices (PVs). A) The power supply mechanism of PVs. B) Attenuation of visible and near‐infrared light in different human tissues. Reproduced with permission.^{[ 480 ]} Copyright 2016, Springer Nature. C) Rigid and inorganic materials for PVs. Adapted with permission.^{[ 482 ]} Copyright 2021, Wiley‐VCH. D) Flexible and inorganic materials for PVs. Reproduced with permission.^{[ 484 ]} Copyright 2020, National Acad Sciences. E) Organic materials for PVs. Reproduced with permission.^{[ 485 ]} Copyright 2021, Elsevier. F) Biodegradable PVs. Reproduced with permission.^{[ 490 ]} Copyright 2015, Royal Society of Chemistry.