Flexible and wearable electronics is one major technology after smartphones. It shows remarkable application potential in displays and informatics, robotics, sports, energy harvesting and storage, and medicine. As an indispensable part and the cornerstone of these devices, soft metal electrodes (SMEs) are of great significance. Compared with conventional physical processes such as vacuum thermal deposition and sputtering, chemical approaches for preparing SMEs show significant advantages in terms of scalability, low-cost, and compatibility with the soft materials and substrates used for the devices. This review article provides a detailed overview on how to chemically fabricate SMEs, including the material preparation, fabrication technologies, methods to characterize their key properties, and representative studies on different wearable applications.

The ever‐growing demand for portable and wearable electronics has driven increased interest in flexible lithium‐ion batteries (LIBs) and supercapacitors (SCs). However, endowing conventional LIBs and SCs with good flexibility and high energy density is challenging, as metal foils and rigid electrodes are easily fractured during flexing. In recent years, textile composite electrodes (TCEs), electrodes coated onto or grown on conductive textile current collectors have shown great promise for application in flexible, high‐capacity/capacitance, and long‐cycle‐life textile‐based electrochemical energy storage devices (TEESDs). This Essay summarizes the advantages of TCEs compared to conventional metal‐foil‐supported electrodes (MFEs) and discusses the integration of TCEs into TEESDs as flexible LIBs and SCs for wearable applications. Finally, the challenges associated with TCEs and TEESDs are discussed alongside an analysis of possible solutions.

Electronic textiles require rechargeable power sources that are highly integrated with textiles and garments, thereby providing outstanding durability and washability. In contrast, present power sources fabricated using conventional ex situ strategies are difficult to integrate with clothing and can degrade during garment washing. Here, a new manufacturing strategy named additive functionalization and embroidery manufacturing (AFEM) is reported, which enables textile‐based supercapacitors (TSCs) to be directly fabricated on woven, knitted, and nonwoven fabrics. The additive principle of AFEM allows developing TSCs with different types of electrode materials, device architectures, pattern designs, and array connections. High‐machine‐speed, programmable‐design industrial embroidering equipment is used to fabricate TSCs with high areal energy storage and power capabilities, which are retained during many cycles of severe mechanical deformation and industrial laundering with waterproof encapsulation.

Because of the large abundance of sodium (Na) as a source material and the easy fabrication of Na‐containing compounds, the sodium (Na) battery is a more environmentally friendly and sustainable technology than the lithium‐ion battery (LIB). Na‐metal batteries (SMBs) are considered promising to realize a high energy density to overtake the cost effectiveness of LIBs, which is critically important in large‐scale applications such as grid energy storage. However, the cycling stability of the Na‐metal anode faces significant challenges particularly under high cycling capacities, due to the complex failure models caused by the formation of Na dendrites. Here, a universal surface strategy, based on a self‐regulating alloy interface of the current collector, to inhibit the formation of Na dendrites is reported. High‐capacity (10 mAh cm−2) Na‐metal anodes can achieve stable cycling for over 1000 h with a low overpotential of 35 mV. When paired with a high‐capacity Na3V2(PO4)2F3 cathode (7 mAh cm−2), the SMB delivers an unprecedented energy density (calculated based on all the cell components) over 200 Wh kg−1 with flooded electrolyte, or over 230 Wh kg−1 with lean electrolyte. The dendrite‐free SMB also shows high cycling stability with a capacity retention per cycle over 99.9% and an ultrahigh energy efficiency of 95.8%.

In article number 2002838, Zijian Zheng and co‐workers provide a critical review of the opportunities and challenges in the field of textile composite electrodes (TCEs) in flexible electrochemi cal energy storage devices. TCEs are compared with traditional metal‐foil‐supported electrodes, focusing particularly on fabrication techniques, electrode structures, and electrochemical and mechanical performance. The layouts of several textile‐based electrochemical energy storage devices are outlined and their integration methods for flexible and wearable electronics discussed.