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To overcome the surface instability of traditional polymeric membranes especially with superwetting behaviour, a robust superhydrophilic surface was fabricated with nano-TiO2 inlaid on a hierarchical polylactide (PLA) ultrafiltration membrane via a spin coating process.

Lithium‐ion batteries are the most commercially successful electrochemical devices, extensively used in intelligent electronics, electric vehicles, grid energy storages, etc. However, there still needs to be further improvement of their performance such as in energy density, cyclability, rate capability, and safety. To do so, it is necessary to understand the detailed structural evolution progress inside the battery. Many advanced imaging techniques have been developed to directly monitor the status and get some key information inside the battery. For advanced imaging techniques, superhigh resolution, fully informative function, nondestruction of the sample, and in situ observation are required. This review introduces and discusses some recent important progress on a variety of advanced imaging techniques for battery research. These imaging techniques have enabled the visualization of sub‐micrometer level chemical valence distribution, evolution of solid‐electrolyte interface, Li dendrite growth, and trace amount of gassing, etc., which greatly promote the development of rechargeable batteries. Of particular note, a new ultrasonic imaging technique has been recently developed to monitor gas generation, the electrolyte wetting process, and the state of charge in the battery. Finally, a perspective is given on some future developments in the imaging techniques for Li‐ion batteries and other rechargeable batteries.

If the preferred growth planes are ( 105), (103), and (002), the crystal grows at an angle of 0-30° from the substrate. If the preferred growth planes are ( 101), ( 102), (112), and (114), the crystal grows at an angle of 30-70° from the substrate. And if the preferred growth planes are ( 100) and ( 110), the crystal grows at an angle of 70-90° from the substrate. [10] By density functional theory (DFT) calculation, Zhu et al. [11] revealed that the binding energies between Zn atom and the (002), (100), and (101) planes of Zn metal are different. The binding energy of (002) plane is the weakest, while that of (101) plane is the strongest, which means that Zn atoms will preferentially deposit on that crystal plane, allowing (101) plane to preferentially grow, and thus resulting in the formation of Zn dendrites. If crystal planes like (105), (103), and (002) can be induced to preferentially grow, it will make deposition layer smoother and inhibit the formation of Zn dendrites. It is worth noting that the preferential growth of ( 105), (103), and (002) planes can form a compact deposition layer to inhibit corrosion and H 2 evolution to a certain extent. [12,13] Therefore, reasonable manipulation of crystal orientation is of great significance for AZIBs.Up to now, the methods of manipulating crystal orientation in AZIBs mainly include optimizing the separator, [14,15] modifying coating layers, [16][17][18][19][20][21][22] using electrolyte additives, [11,[23][24][25][26][27][28] and processing/heating treatment of the Zn anode. [12,13,29] In the above methods, using electrolyte additives is much attractive because of its convenience and cost-effectiveness. [30][31][32] Electrolyte additives such as Mn 2+ +gelatin, SBT, OTf 2− , H 3 PO 4 , In 2 (SO 4 ) 3 , H 3 BO 3 , CTAB, SDS, TU, and PEG-8000 have been employed to induce preferential growth of specific crystal planes. [11,[23][24][25][26][27][28] Nevertheless, most of these researches require pre-preparation of Zn anodes with specific crystal planes such as (002), [11,[25][26][27][28] which makes the process complicated. And most works only focused on the orientation change of Zn crystals after a single electrodeposition. It is worth noting that almost all of these works were unable to maintain a long cycle life under the condition of high current density and large areal capacity, which may be related to the weakened effect of electrolyte additives due to the structural reconstruction of Zn anode over cycling. [11] Therefore, it is crucial to systematically Uncontrolled growth of Zn dendrites is the main reason for the short-circuit failure of aqueous Zn-ion batteries. Using electrolyte additives to manipulate the crystal growth is one of the most convenient strategies to mitigate the dendrite issue. However, most additives would be unstable during cycling due to the structural reconstruction of the deposition layer. Herein, it is proposed to use 1-butyl-3-methylimidazolium cation (BMIm + ion) as an electrolyte additive, which could steadily induce the preferential ...

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It has long been a global imperative to develop high‐energy‐density lithium‐ion batteries (LIBs) to meet the ever‐growing electric vehicle market. One of the most effective strategies for boosting the energy density of LIBs is to increase the output voltage, which largely depends upon the cathode materials. As the most‐promising cathodes for high‐voltage LIBs (>4 V vs Li/Li+), four major categories of cathodes including lithium‐rich layered oxides, nickel‐rich layered oxides, spinel oxides, and high‐voltage polyanionic compounds still encounter severe challenges to realize the improvement of output voltage while maintaining high capacity, fast rate capability, and long service life. This review focuses on the key links in the development of high‐voltage cathode materials from the lab to industrialization. First, the failure mechanisms of the four kinds of materials are clarified, and the optimization strategies, particularly solutions that are easy for large‐scale production, are considered. Then, to bridge the gap between lab and industry, the cost management, safety assessment, practical battery‐performance evaluation, and sustainability of the battery technologies, are discussed. Finally, tough challenges and promising strategies for the commercialization of high‐voltage cathode materials are summarized to promote the large‐scale application of LIBs with high energy densities.

Using a solid‐state electrolyte (SSE) to stabilize the Li metal anode is widely considered a promising route to develop next‐generation high energy density lithium batteries. Here, a new polycrystalline aluminate‐based SSE (named Li–Al–O SSE) with good capability is introduced to protect Li metal. The SSE is formed on the Li metal surface via a chemical reaction between LiOH and triethylaluminum (TEAL) with the existence of LiTFSI‐based electrolyte. It is a continuous film that consists of polycrystalline LiAlO2, Li3AlO3, Al2O3, Li2CO3, LiF, and some organic compounds. Such Li–Al–O SSE possesses a room‐temperature ionic conductivity as high as 1.42 × 10−4 S cm−1. Meanwhile, it effectively protects the Li anode from the corrosion of H2O, O2, and organic solvent, and suppresses the growth of Li dendrite. With the protection of the Li–Al–O SSE, the cycle life of Li|Li symmetric cell and Li|O2 cell is substantially elongated, indicating that the SSE exhibits an excellent protective effect under both inert and oxidizing circumstances.