• Energy Research

Here we report an approach to roll out Li-ion battery components from silicon chips by a continuous and repeatable etch-infiltrate-peel cycle. Vertically aligned silicon nanowires etched from recycled silicon wafers are captured in a polymer matrix that operates as Li + gel-electrolyte and electrode separator and peeled off to make multiple battery devices out of a single wafer. Porous, electrically interconnected copper nanoshells are conformally deposited around the silicon nanowires to stabilize the electrodes over extended cycles and provide efficient current collection. Using the above developed process we demonstrate an operational full cell 3.4 V lithium-polymer silicon nanowire (LIPOSIL) battery which is mechanically flexible and scalable to large dimensions.

Mg-ion diffusion in cathodes and dissociation in electrolyte complexes are sluggish processes that hinder the development of Mg batteries. Now, a new design of both the cathode and the electrolyte drastically improves the kinetics of these processes, leading to a high-power Mg battery.

AbstractControlling redox activity of judiciously appended redox units on a photo‐sensitive molecular core is an effective strategy for visible light energy harvesting and storage. The first example of a photosensitizer ‐ electron donor coordination compound in which the photoinduced electron transfer step is used for light to electrical energy conversion and storage is reported. A photo‐responsive Ru‐diimine module conjugated with redox‐active catechol groups in [Ru(II)(phenanthroline‐5,6‐diolate)3]4− photosensitizer can mediate photoinduced catechol to dione oxidation in the presence of a sacrificial electron acceptor or at the surface of an electrode. Under potentiostatic condition, visible light triggered current density enhancement confirmed the light harvesting ability of this photosensitizer. Upon implementation in galvanostatic charge‐discharge of a Li battery configuration, the storage capacity was found to be increased by 100 %, under 470 nm illumination with output power of 4.0 mW/cm−2. This proof‐of‐concept molecular system marks an important milestone towards a new generation of molecular photo‐rechargeable materials.

Organic electrode materials have garnered a great deal of interest owing to their sustainability, cost-efficiency, and design flexibility metrics.

AbstractEnergy storage devices that provide high specific power without compromising on specific energy are highly desirable for many electric-powered applications. Here, we demonstrate that polymer organic radical gel materials support fast bulk-redox charge storage, commensurate to surface double layer ion exchange at carbon electrodes. When integrated with a carbon-based electrical double layer capacitor, nearly ideal electrode properties such as high electrical and ionic conductivity, fast bulk redox and surface charge storage as well as excellent cycling stability are attained. Such hybrid carbon redox-polymer-gel electrodes support unprecedented discharge rate of 1,000C with 50% of the nominal capacity delivered in less than 2 seconds. Devices made with such electrodes hold the potential for battery-scale energy storage while attaining supercapacitor-like power performances.

Li-ion microbatteries are the frontline candidates to fulfill the requirements of powering miniature autonomous devices. However, it still remains challenging to attain the required energy densities of > 0.3mWh cm−2 μm−1 in a planar configuration. To overcome this limitation, 3D architectures of LIMBs have been proposed. However, most deposition techniques are poorly compatible with 3D architectures because they limit the choice of current collectors and selective deposition of the active materials. Electrodeposition was suggested as an alternative for rapidly and reproducibly depositing active materials under mild conditions, and with controlled properties. However, despite the huge potential, electrodeposition remains underexplored for LIMB cathode materials, partly due to challenges associated with the electrodeposition of Li-ion phases. Herein, we review advances in the electrodeposition of Li-ion cathode materials with the main focus set on the direct, one-step deposition of electrochemically active phases. We highlight the merits of electrodeposition over other methods and discuss the various classes of reported materials, including layered transition metal oxides, vanadates, spinel, and olivines. We offer a perspective on the future advances for the adoption of electrodeposition processes for the fabrication of microbatteries to pave the way for future research on the electrodeposition of cathode materials.

An alkali-rich organic redox system, A6THBPD, enables high-capacity, high-voltage Li-, Na-, and K-ion storage. Delivering up to 4e− per unit and strong full-cell output, A6THBPD advances high-energy organic materials for alkali-ion batteries.