Lithium ion capacitors (LICs), which are hybrid electrochemical energy storage devices combining the intercalation/deintercalation mechanism of a lithium‐ion battery (LIB) electrode with the adsorption/desorption mechanism of an electric double‐layer capacitor (EDLC) electrode, have been extensively investigated during the past few years by virtue of their high energy density, rapid power output, and excellent cycleability. In this review, the LICs are defined as the devices with an electrochemical intercalation electrode and a capacitive electrode in organic electrolytes. Both electrodes can serve as anode or cathode. Throughout the history of LICs, tremendous efforts have been devoted to design suitable electrode materials or develop novel type LIC systems. However, one of the key challenges encountered by LICs is how to balance the sluggish kinetics of intercalation electrodes with high specific capacity against the high power characteristics of capacitive electrode with low specific capacitance. Herein, the developments and the latest advances of LIC in material design strategies and key techniques according to the basic scientific problems are summarized. Perspectives for further development of LICs toward practical applications are also proposed.

All solid‐state batteries holds great promise for superiorly safe and high energy electrochemical energy storage. The ionic conductivity of electrolytes and its interfacial compatibility with the electrode are two critical factors in determining the electrochemical performance of all solid‐state batteries. It is a great challenge to simultaneously demonstrate fantastic ionic conductivity and compatible electrolyte/electrode interface to acquire a well‐performed all solid‐state battery. By in situ polymerizing poly(ethylene glycol) methyl ether acrylate within a self‐supported 3D porous Li‐argyrodite (Li6PS5Cl) skeleton, the two bottlenecks are tackled successfully at once. As a result, all solid‐state lithium metal batteries with a 4.5 V LiNi0.8Mn0.1Co0.1O2 cathode designed by this integrated strategy demonstrates a high Coulombic efficiency exceeding 99% at room temperature. Solid‐state nuclear magnetic resonance data suggest that Li+ mainly migrates along the continuous Li6PS5Cl phase to result in a room temperature conductivity of 4.6 × 10−4 S cm−1, which is 128 times higher than that of the corresponding polymer. Meanwhile, the inferior solid–solid electrolyte/electrode interface is integrated via in situ polymerization to lessen the interfacial resistance significantly. This study thereby provides a very promising strategy of solid electrolyte design to simultaneously meet both high ionic conductivity and good interfacial compatibility towards practical high‐energy‐density all solid‐state lithium batteries.

Dual‐ion batteries (DIBs) with high operation voltage offer promising candidates for low‐cost clean energy chemistries. However, there still exist tough issues, including structural collapse of the graphite cathode due to solvent co‐intercalation and electrolyte decomposition on the electrode/electrolyte interface, which results in unsatisfactory cyclability and fast battery failure. Herein, Li4Ti5O12 (LTO) modified mesocarbon microbeads (MCMBs) are proposed as a cathode material. The LTO layer functions as a skeleton and offers electrocatalytic active sites for in situ generation of a favorable and compatible cathode electrolyte interface (CEI) layer. The synergetic LTO‐CEI network can change the thermodynamic behavior of the PF6− intercalation process and maintain the structural integrity of the graphite cathode, as a “Great Wall” to protect the cathode from structural collapse and electrolyte decomposition. Such LTO‐CEI reinforced cathode exhibits a prolonged cyclability with 85.1% capacity retention after 2000 cycles even at cut‐off potential of 5.4 V versus Li+/Li. Moreover, the LTO‐modified MCMB (+)//prelithiated MCMB (−) full cell exhibits a high energy density of ≈200 Wh kg−1, remarkably enhanced cyclability with 93.5% capacity retention after 1000 cycles. Undoubtedly, this work offers in‐depth insight into interface chemistry, which can arouse new originality to boost the development of DIBs.

Conventional carbonate solvents with lowH OMO levels are theoretically compatible with the low-cost, highvoltage chemistry of Zn/graphite batteries.H owever,t he nucleophilic attacko ft he anion on carbonates induces an oxidative breakdown at high potentials.H ere,w er estore the inherent anodic stability of carbonate electrolytes by designing amicro-heterogeneous anion solvation network. Based on the addition of as trongly electron-donating solvent, trimethyl phosphate (TMP), the oxidation-vulnerable anion-carbonate affinities are decoupled because of the preferential sequestration of anions into solvating TMP domains around the metal cations.The hybridized electrolytes elevate the electrochemical window of carbonate electrolytes by 0.45 Va nd enable the operation of Zn/graphite dual-ion cells at 2.80 Vw ith al ong cycle life (92 %c apacity retention after 1000 cycles). By inheriting the non-flammability from TMP and the high iontransport kinetics from the carbonate systems,t his facile strategy provides cells with the additional benefits of fire retardancy and high-power capability.