Microscale supercapacitors provide an important complement to batteries in a variety of applications, including portable electronics. Although they can be manufactured using a number of printing and lithography techniques, continued improvements in cost, scalability and form factor are required to realize their full potential. Here, we demonstrate the scalable fabrication of a new type of all-carbon, monolithic supercapacitor by laser reduction and patterning of graphite oxide films. We pattern both in-plane and conventional electrodes consisting of reduced graphite oxide with micrometre resolution, between which graphite oxide serves as a solid electrolyte. The substantial amounts of trapped water in the graphite oxide makes it simultaneously a good ionic conductor and an electrical insulator, allowing it to serve as both an electrolyte and an electrode separator with ion transport characteristics similar to that observed for Nafion membranes. The resulting micro-supercapacitor devices show good cyclic stability, and energy storage capacities comparable to existing thin-film supercapacitors.

all need to be used in conjugation with an energy storage system to provide smooth power leveling. Currently, electrochemical energy storage systems are by far the most optimal solutions for powering a broad range of technologies, expanding from compact and light-weighted portable electronic devices to stationary gridscale energy storage applications. [3][4][5][6] These energy storage devices (batteries and supercapacitors) store the available electrical energy in the form of chemical energy and release it whenever needed, by simply reversing the electrochemical reaction. [7][8][9][10][11] Among various available battery chemistries, lithium batteries and supercapacitors are the most promising technologies. [ 7,[9][10][11][12][13][14][15][16][17][18][19][20] Ever since the realization of the fi rst electrochemical energy storage cell by Alessandro Volta (end of 17th century), the working principle and its function has changed very little. [ 21,22 ] Basically, two redox couples (or charge storage electrodes), electrically and physically separated, are bridged by an ion conducting medium to constitute an electrochemical cell. This holds true also for modern Li-ion batteries, although the chemistry involved is much more complex. During operation, the electrons are transferred through an external circuit while ions shuttle through the electrolyte to counterbalance the depleted charge at the electrodes. [ 23 ] So far, much of the effort has been directed towards improvement of the energy and power characteristics by downsizing the active components, re-engineering the current collectors and separators, as well as fi ne-tuning the Batteries have become fundamental building blocks for the mobility of modern society. Continuous development of novel battery chemistries and electrode materials has nourished progress in building better batteries. Simultaneously, novel device form factors and designs with multi-functional components have been proposed, requiring batteries to not only integrate seamlessly to these devices, but to also be a multi-functional component for a multitude of applications. Thus, in the past decade, along with developments in the component materials, the focus has been shifting more and more towards novel fabrication processes, unconventional confi gurations, and additional functionalities. This work attempts to critically review the developments with respect to emerging electrochemical energy storage confi gurations, including, amongst others, paintable, transparent, fl exible, wire or cable shaped, ultra-thin and ultra-thick confi gurations, as well as hybrid energy storage-conversion, or graphene-incorporated batteries and supercapacitors. The performance requirements are elaborated together with the advantages, but also the limitations, with respect to established electrochemical energy storage technologies. Finally, challenges in developing novel materials with tailored properties that would allow such confi gurations, and in designing easier manufacturing techniques that can be widely adopted ar...

High energy and high power electrochemical energy storage devices rely on different fundamental working principles - bulk vs. surface ion diffusion and electron conduction. Meeting both characteristics within a single or a pair of materials has been under intense investigations yet, severely hindered by intrinsic materials limitations. Here, we provide a solution to this issue and present an approach to design high energy and high power battery electrodes by hybridizing a nitroxide-polymer redox supercapacitor (PTMA) with a Li-ion battery material (LiFePO4). The PTMA constituent dominates the hybrid battery charge process and postpones the LiFePO4 voltage rise by virtue of its ultra-fast electrochemical response and higher working potential. We detail on a unique sequential charging mechanism in the hybrid electrode: PTMA undergoes oxidation to form high-potential redox species, which subsequently relax and charge the LiFePO4 by an internal charge transfer process. A rate capability equivalent to full battery recharge in less than 5 minutes is demonstrated. As a result of hybrid's components synergy, enhanced power and energy density as well as superior cycling stability are obtained, otherwise difficult to achieve from separate constituents.

If the components of a battery, including electrodes, separator, electrolyte and the current collectors can be designed as paints and applied sequentially to build a complete battery, on any arbitrary surface, it would have significant impact on the design, implementation and integration of energy storage devices. Here, we establish a paradigm change in battery assembly by fabricating rechargeable Li-ion batteries solely by multi-step spray painting of its components on a variety of materials such as metals, glass, glazed ceramics and flexible polymer substrates. We also demonstrate the possibility of interconnected modular spray painted battery units to be coupled to energy conversion devices such as solar cells, with possibilities of building standalone energy capture-storage hybrid devices in different configurations.