Lithium–sulfur (Li–S) batteries with high sulfur loading are urgently required in order to take advantage of their high theoretical energy density. Ether‐based Li–S batteries involve sophisticated multistep solid–liquid–solid–solid electrochemical reaction mechanisms. Recently, studies on Li–S batteries have widely focused on the initial solid (sulfur)–liquid (soluble polysulfide)–solid (Li2S2) conversion reactions, which contribute to the first 50% of the theoretical capacity of the Li–S batteries. Nonetheless, the sluggish kinetics of the solid–solid conversion from solid‐state intermediate product Li2S2 to the final discharge product Li2S (corresponding to the last 50% of the theoretical capacity) leads to the premature end of discharge, resulting in low discharge capacity output and low sulfur utilization. To tackle the aforementioned issue, a catalyst of amorphous cobalt sulfide (CoS3) is proposed to decrease the dissociation energy of Li2S2 and propel the electrochemical transformation of Li2S2 to Li2S. The CoS3 catalyst plays a critical role in improving the sulfur utilization, especially in high‐loading sulfur cathodes (3–10 mg cm−2). Accordingly, the Li2S/Li2S2 ratio in the discharge products increased to 5.60/1 from 1/1.63 with CoS3 catalyst, resulting in a sulfur utilization increase of 20% (335 mAh g−1) compared to the counterpart sulfur electrode without CoS3.

Solid-state batteries have been considered as one of the most promising next-generation energy storage systems because of their high safety and energy density. Solid-state electrolytes are the key component of the solid-state battery, which exhibit high ionic conductivity, good chemical stability, and wide electrochemical windows. LATP [LiAlTi (PO)] solid electrolyte has been widely investigated for its high ionic conductivity. Nevertheless, the chemical instability of LATP against Li metal has hindered its application in solid-state batteries. Here, we propose that atomic layer deposition (ALD) coating on LATP surfaces is able to stabilize the LATP/Li interface by reducing the side reactions. In comparison with bare LATP, the AlO-coated LATP by ALD exhibits a stable cycling behavior with smaller voltage hysteresis for 600 h, as well as small resistance. More importantly, on the basis of advanced characterizations such as high-resolution transmission electron spectroscope-electron energy loss spectroscopy, the lithium penetration into the LATP bulk and Ti reduction are significantly limited. The results suggest that ALD is very effective in improving solid-state electrolyte/electrode interface stability.

Na metal anode attracts increasing attention as a promising candidate for Na metal batteries (NMBs) due to the high specific capacity and low potential. However, similar to issues faced with the use of Li metal anode, crucial problems for metallic Na anode remain, including serious moss-like and dendritic Na growth, unstable solid electrolyte interphase formation, and large infinite volume changes. Here, the rational design of carbon paper (CP) with N-doped carbon nanotubes (NCNTs) as a 3D host to obtain Na@CP-NCNTs composites electrodes for NMBs is demonstrated. In this design, 3D carbon paper plays a role as a skeleton for Na metal anode while vertical N-doped carbon nanotubes can effectively decrease the contact angle between CP and liquid metal Na, which is termed as being "Na-philic." In addition, the cross-conductive network characteristic of CP and NCNTs can decrease the effective local current density, resulting in uniform Na nucleation. Therefore, the as-prepared Na@CP-NCNT exhibits stable electrochemical plating/stripping performance in symmetrical cells even when using a high capacity of 3 mAh cm at high current density. Furthermore, the 3D skeleton structure is observed to be intact following electrochemical cycling with minimum volume change and is dendrite-free in nature.

Nowadays, fast charging ability of energy storage devices is essential for applications in electric vehicles and electrical power grids. The fast charging performance of batteries is enabled by highrate electrode materials. which have been realized through various methods such as nanosizing, porous structures, carboncoatings, and conductive materials-based hierarchical structures. [1] Nanosizing and porous structures can enhance the lithium-ion transport as they reduce the distance lithium ions have to diffuse in the solid electrode, and they also enlarge the contact area between the liquid electrolyte and the electrode material. [2] Carbon-coatings and conductive materials (e.g., graphene or Mxene) based hierarchical structures can enhance the electrical conductivity of the electrodes to enable higher current densities. [3] However, nanosizing and porous structures lead to a reduction of the specific volumetric capacity, while composites with carbon-based conductive materials require the electrode to discharge down to 0.01 V resulting in lithium dendrite formation under high current densities. [4][5][6] The formation of nanostructures can even result in a reduced electrochemical performance at high C rates as compared to their bulk materials due to possible morphology change, nanostructure collapse, and higher first-cycle capacity loss. [7][8][9] Furthermore, the fabrication of these delicate nano-architectures, porous structures, and composites usually require harsh synthesis environments, expensive reactants, and multiple synthesis steps, which results in a complex and expensive synthesis process. Additionally, such synthesis methods often provide either relatively low yields or significant amounts of chemical waste.Recent studies increasingly focus on the development of electrode materials with an intrinsic high-rate performance by combining the advantages of exhibiting 1) a suitable host structure for fast lithium-ion intercalation, 2) a lower bandgap to enhance the electrical conductivity, and 3) a higher working voltage to avoid lithium dendrite formation. Titanium-based oxides, such as Li 4 Ti 5 O 12 and anatase TiO 2 , are well known as interesting electrode materials, while they exhibit working voltages of 1.55 and 1.8 V, [10,11] respectively, preventing lithium plating. However, in order to obtain high rate performance,

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