and fi lms can be assembled on substrates with this versatile method. Film thickness, particle size and inter structure of EPD fi lms are controllable by adjusting the suspension/process parameters. [ 2,3 ] Energy conversion and storage devices have been developed rapidly in the past few decades, and proposed as the foundation of modern society. Novel carbon materials such as graphene and carbon nanotubes (CNTs) are investigated widely for high-effi ciency rechargeable battery and supercapacitor (SC) applications. [ 4,5 ] Traditional methods such as blade coating and slot die are employed to prepare electrodes to realize such applications. [ 6,7 ] In these methods, active materials are dissolved into a solvent to form a viscous solution, and a fi lm is obtained after coating and solvent evaporation. Nevertheless, neither thickness control nor a high fi lm assembly effi ciency can be realized via these methods. In addition, traditional methods exhibit limitation on the fabrication of nanostructured energy materials due to the aggregation of nanoparticles. On the other hand, methods for micro-batteries such as vapor deposition methods, [ 8 ] radio-frequency sputtering, [ 9 ] and pulsed laser deposition [ 10,11 ] are expensive and diffi cult to scale up. Indeed, a versatile EPD technique with cost-effectiveness, short formation time, and high scalability is promising for efficient fabrication of energy conversion and storage materials and devices. A typical EPD process is performed in two steps, including the dispersion of powder particles in a solvent to form a stable suspension and the deposition of particles on a substrate in the presence of an electric fi eld. [ 12,13 ] Preparation of a stable suspension is essential to the deposition process. The stability of suspension, adjustable with surfactants, is correlated with electrostatic repulsive and van der Waals attractive interactions. The stability of suspension/colloid is characterized by zeta potential, the value of which represents the magnitude of repulsive interaction while the sign represents the migration direction of particles. Zeta potential is mainly determined by temperature, pH, and type of surfactant. On the other hand, the migration velocity of particles in deposition depends on the applied voltage/current, particle size, zeta potential, suspension concentration, and solvent viscosity. [ 14 ] The utilization of EPD in the energy storage/conversion devices fi eld enables the direct deposition of active particles on the current collector.Featuring pronounced controllability, versatility, and scalability, electrophoretic deposition (EPD) has been proposed as an effi cient method for fi lm assembly and electrode/solid electrolyte fabrication in various energy storage/conversion devices including rechargeable batteries, supercapacitors, and fuel cells. High-quality electrodes and solid electrolytes have been prepared through EPD and exhibit advantageous performances in comparison with those realized with traditional methods. Recent advances in the appli...

The application of current polymer lithium‐ion batteries is still challenged with the limited electrochemical performance and thermal stability of polymeric electrolyte membranes as battery separators. In this report, an efficient route to polymeric polyvinylidene fluoride‐hexafluoropropylene electrolyte membranes with interparticle chain microstructure is presented. The structure is capable of hosting sufficient electrolyte for efficient migration of electrolyte salts. The electrolyte uptake ratio is up to 188.4% and the highest ionic conductivity reaches 1.08 mS cm−1 at room temperature. In particular, the membrane exhibits higher thermal resistance compared with traditional separators, only giving rise to a subtle shrinkage at 175 °C and allows for efficient battery operation for a record number of charge/discharge cycles at 110 °C. The electrolyte membrane through such a single‐step method shows promising application potentials in electric vehicles and wearable electronics, especially in extreme operation conditions.

High-power lithium ion batteries (LIBs) have extensive applications ranging from electronic devices to electric vehicles. The composition and structure of separators largely impact the rate performances of LIBs. Here, a three-dimensional (3D) nanoporous poly(vinylidenefluoride-hexafluoropropylene) (PVDF-HFP)-polyethylene (PE) composite separator is obtained through solvent liberation. The composite separator owns a high ionic conductivity of 1.01 mS•cm lithium ion batteries (LIBs) have extensive applications ranging from electronic devices to electric vehicles. The composition and structure of separators largely impact the rate performances of LIBs. Here, a three-dimensional (3D) nanoporous poly( −1 at room temperature due to the high porosity up to 95.6% and the uniform 3D pore distribution. LiFePO 4 /Li half-cells with the composite separator deliver record rate capacities of 97 mAh•g −1 at 10 C and 57 mAh•g −1 at 20 C. PE in the composite separator significantly enhances the mechanical strength and thermal stability of the separator. Theoretical calculations show that the difference in the absorption energy between acetone and NMP solvent on PVDF-HFP is the major driving force for the formation of the inter-island structure, which provides massive Li + transport channels during high-rate battery cycling.

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