How to Pack a Punch – Why 3D Batteries are Essential

The miniaturization of implantable medical devices, remote microsensors and transmitters, “smart” cards, and Internet of Things (IoT) systems is impeded by the absence of high-performance micro-size power sources. Insufficient areal energy density from thin-film planar microbatteries has inspired a search for three-dimensional microbatteries (3DMB) with the use of low-cost and efficient micro- and nano-scale materials and techniques. In our short review, we present our outlook on the state-of-the-art development of advanced 3D-microbattery designs and methods of the fabrication of electrode materials. Special attention is given to the 3D-printing approach, which holds many opportunities for the mass production of microbatteries and their direct integration with electronic devices.