Organic rechargeable batteries, which use organics as electrodes, are excellent candidates for next-generation energy storage systems because they offer design flexibility due to the rich chemistry of organics while being eco-friendly and potentially cost efficient. However, their widespread usage is limited by intrinsic problems such as poor electronic conductivity, easy dissolution into liquid electrolytes, and low volumetric energy density. New types of organic electrode materials with various redox centers or molecular structures have been developed over the past few decades. Moreover, research aimed at enhancing electrochemical properties via chemical tuning has been at the forefront of organic rechargeable batteries research in recent years, leading to significant progress in their performance. Here, an overview of the current developments of organic rechargeable batteries is presented, with a brief history of research in this field. Various strategies for improving organic electrode materials are discussed with respect to tuning intrinsic properties of organics using molecular modification and optimizing their properties at the electrode level. A comprehensive understanding of the progress in organic electrode materials is provided along with the fundamental science governing their performance in rechargeable batteries thus a guide is presented to the optimal design strategies to improve the electrochemical performance for next-generation battery systems.

The development of safe, reliable, yet economical energy storage has been reemphasized with recent incidents involving the explosion and subsequent recall of lithium‐ion batteries. The organic liquid electrolyte used in the conventional lithium‐ion battery can potentially act as a fuel for combustion in a thermal‐runaway reaction, and hence an alternative with a significantly reduced flammability must be sought. All‐solid‐state batteries have the potential to meet safety and reliability requirements with the possibility of increasing the volumetric energy density of the system, making these a promising candidate for the development of the next generation of energy storage. Moreover, the sodium‐ion battery exhibits a better cost‐efficiency without significantly compromising the energy density, making the combination of the sodium chemistry with the solid electrolyte an attractive choice for safe and economical energy storage. Here, a general background on the recent development of ceramic and glass‐ceramic sodium‐ion‐conducting electrolytes is provided with regard to oxide‐, sulfide‐, and hydride‐based electrolytes. The ionic conductivity, chemical stability, and mechanical properties of the sodium‐based solid electrolyte are discussed, which is followed by a perspective on future developments in the field.

Conservative management without anticoagulation can be applied successfully to the patients with symptomatic SIDSMA. Primary endovascular stenting is indicated if patients have suspected bowel ischemia, compression of the true lumen of the SMA >80%, or SMA aneurysm of >2.0 cm in diameter on initial CT scan. Endovascular stenting can also be provided to the patients in whom initial conservative treatment failed, as a rescue therapy.

Lithium metal batteries using solid electrolytes are considered to be the next-generation lithium batteries due to their enhanced energy density and safety. However, interfacial instabilities between Li-metal and solid electrolytes limit their implementation in practical batteries. Herein, Li-metal batteries using tailored garnet-type Li7-xLa3-aZr2-bO12 (LLZO) solid electrolytes is reported, which shows remarkable stability and energy density, meeting the lifespan requirements of commercial applications. We demonstrate that the compatibility between LLZO and lithium metal is crucial for long-term stability, which is accomplished by bulk dopant regulating and dopant-specific interfacial treatment using protonation/etching. An all-solid-state with 5 mAh cm−2 cathode delivers a cumulative capacity of over 4000 mAh cm−2 at 3 mA cm−2, which to the best of our knowledge, is the highest cycling parameter reported for Li-metal batteries with LLZOs. These findings are expected to promote the development of solid-state Li-metal batteries by highlighting the efficacy of the coupled bulk and interface doping of solid electrolytes.

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Figure 1. Schematic illustration of the main challenges faced in SSLMBs.

The thermodynamic instability of the LiCoO2 layered structure at >0.5Li extraction has been considered an obstacle for the reversible utilization of its near theoretical capacity at high cutoff voltage (>4.6 V vs Li/Li+) in lithium-ion batteries. Many previous studies have focused on resolving this issue by surface modification of LiCoO2, which has proven to be effective in suppressing phase transformation. To determine the extent to which surface protection of LiCoO2 is effective despite its thermodynamic instability and presumably incomplete reversibility involving the O1 phase, here we verify the intrinsic reversibility of bulk LiCoO2 with extended lithium extraction by ruling out the effect of a surface. Specifically, first, we show that, contrary to conventional belief, electrochemical cycling of LiCoO2 at a cutoff voltage of 4.8 V (vs Li/Li+) results in better cycle stability and lower polarizations than those at 4.6 V. We demonstrate, using an exhaustive suite of characterization tools, that the rapid cycle degradation under high-voltage cycling is mostly caused by the formation of a surface resistive layer; however, these damaged surfaces are leached out faster than they are accumulated above a certain potential, which results in superior cyclability compared with that achieved for less oxidative 4.6-V cycling. This beneficial leaching out of the resistive surface layer serves as a “subtractive” surface modification and plays a role in enhancing the cycle stability and is distinguished from conventional “additive” surface modification such as coating. This approach allows us to decouple factors of the bulk and surface degradations that contribute to the capacity fade and leads to the finding that, in the absence of a resistive surface, the capacity retention of a LiCoO2 electrode with 4.8-V cutoff cycling can be intrinsically high, indicating that the instability of the crystalline Li x CoO2 (x < 0.5) has a limited effect on the cycle stability. Our findings also explain why the strategy of coating foreign materials on the surface of LiCoO2 can improve the high-voltage cycling to some extent despite the expected thermodynamic instability of the highly charged phase.

Lithium dendrite growth in solid electrolytes is one of the major obstacles to the commercialization of solid-state batteries based on garnet-type solid electrolytes. Herein, we propose a strategy that can simultaneously resolve both the interface and electronic conductivity issues via a simple one-step procedure that provides multilayer protection at low temperature. We take advantage of the facile chemical conversion reaction, showing the wet-coated SnF 2 particles on the solid electrolyte effectively produces a multifunctional interface composed of LiF and Li−Sn alloy upon contact with lithium. We demonstrate the multifunctional interface enables the remarkably high critical current density up to 2.4 mA cm −2 at 25 °C and the stable galvanostatic cycling for over 1000 h at 0.5 mA cm −2 in the lithium symmetric cell. Moreover, the full cell delivers a robust cycle life of more than 600 cycles at 1.0 mA cm −2 , which is the highest performance at room temperature reported to date.