3D Magnetic Metal‐Organic Frameworks Current Collectors Accelerate the Lithium‐Ion Diffusion Rate for Superlong Cyclic Lithium Metal Anode

Abstract Lithium, is the most ideal anode material for lithium‐based batteries. However, the overgrowth of lithium dendrites and the low lithium‐ion diffusion rate at low temperatures limit the further application of lithium metal anodes. Here, the applied magnetic field is introduced inside the lithium metal anode by using a novel magnetic metal‐organic framework as a current collector. The magnetic field can improve the conductivity of this novel current collector, thus accelerating the diffusion of lithium ions in the battery, an advantage that is particularly prominent at low temperatures. In addition, the current collector can stabilize the solid electrolyte interface and inhibit the growth of lithium dendrites, resulting in excellent electrochemical performance. The symmetrical cell at room temperature can exceed 4600 h with a hysteresis voltage of only 9 mV. After 300 cycles at room temperature, the capacity of full cell is still 142 mA h g −1 , and it remains stable for 380 cycles at 5 °C (capacity above 120 mA h g −1 ). The strategy of constructing novel current collector with magnetic field can promote the further application of lithium batteries in extreme conditions such as low temperatures.