Fast-charging and dendrite-free lithium metal anode enabled by partial lithiation of graphene aerogel

The development of deeply cyclable lithium metal batteries with fast-charging capability offers a promising solution to relieve the “range anxiety” in driving electric vehicles. Conventional lithium metal anodes suffered from low operating current densities and shallow charge/discharge depths, owing to the intrinsic dendrite growth governed by Sand’s law. Herein, we come up with a novel design of heavy-duty lithium metal anode fabricated by partially infusing the three-dimensional (3D) porous graphene aerogel with molten Li. Both electroanalytical measurements and simulations show that the unique electrode architecture brings notable advantages in mediating smooth Li plating/stripping, including reduced local current density, inhibited dendrite growth, buffered volume fluctuation, as well as more efficient Li utilization. Consequently, a remarkable cycling performance in symmetric cells for over 400 cycles (800 h) with an ultrahigh cycling capacity of 15 mAh·cm−2 at 15 mA·cm−2 is achieved, which, to our best knowledge, has been never seen in literature. LiFePO4 full cells demonstrate a superb rate capability up to 10 C and a prolonged cycling of 1,600 cycles at 2 C with the per-cycle capacity decay of only 0.023%. This study paves the way for the ultimate deployment of lithium metal batteries in real-world applications that require fast charging and deep cycling.