Fossil fuel is the main energy resource currently. The continuous consumption of this nonrenewable resource has caused very serious environment problems, which has motivated tremendous research efforts in this century. Energy storage is critical to alleviate the current energy and environmental problems. Comparing to mechanical energy storage, rechargeable batteries allow energy storage with a smaller footprint. The intersection of rechargeable battery with nanomaterials has been a booming research topic recently and yielded new applications of nanomaterials as well as new solutions to many long-lived problems in battery science and technology. In this Perspective, we highlight the most recent (2015–2017) examples across lithium, sodium and zinc battery chemistries, where nanoscale materials tailoring and design addresses the intrinsic problems and limitations at both the materials level and device level. And a few principles are generalized at the end.

Batteries represent the dominant means for storing electrical energy, but many battery chemistries create waste streams that are difficult to manage, and most possess toxic components that limit their use...

Degradable polymer matrices and porous scaffolds provide powerful mechanisms for passive, sustained release of drugs relevant to the treatment of a broad range of diseases and conditions. Growing interest is in active control of pharmacokinetics tailored to the needs of the patient via programmable engineering platforms that include power sources, delivery mechanisms, communication hardware, and associated electronics, most typically in forms that require surgical extraction after a period of use. Here we report a light-controlled, self-powered technology that bypasses key disadvantages of these systems, in an overall design that is bioresorbable. Programmability relies on the use of an external light source to illuminate an implanted, wavelength-sensitive phototransistor to trigger a short circuit in an electrochemical cell structure that includes a metal gate valve as its anode. Consequent electrochemical corrosion eliminates the gate, thereby opening an underlying reservoir to release a dose of drugs by passive diffusion into surrounding tissue. A wavelength-division multiplexing strategy allows release to be programmed from any one or any arbitrary combination of a collection of reservoirs built into an integrated device. Studies of various bioresorbable electrode materials define the key considerations and guide optimized choices in designs. In vivo demonstrations of programmed release of lidocaine adjacent the sciatic nerves in rat models illustrate the functionality in the context of pain management, an essential aspect of patient care that could benefit from the results presented here.