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Graphene has been wildly used as a host to suppress dendrite growth to stabilize the lithium metal anode. However, the high overpotential of lithium deposition on pure graphene has to be lowered by doping or employing precious metals. Additionally, the soft nature of graphene rendered itself to aggregate, consequently squeezing room for lithium accommodation. Herein, a tough graphene framework composed of 3D periodic hollow spheres was reported as a free-standing host to stabilize lithium metal anodes. The prepared 3D periodic hollow structure not merely reinforces the framework to maintain hollow structure under pressure caused by assembling battery, but also lowers the overpotential without the help of dopant or precious metals. It is worthy to note that high efficiency of ion diffusion, thanks to the channels interconnecting hollow spheres by holes on the walls, benefits both suppression of lithium dendrite and rate capability. The properties of low density and high mechanical strength make graphene frameworks electrode a promising lightweight Li host material, which reveals a new avenue for designing high-energy density electrode materials.

Although the primary lithium/fluorinated graphite battery has a high energy density of 3725 Wh kg−1, its complete irreversibility based on a conversion reaction between Li and fluorinated graphite hampers wide applications in rechargeable systems. Here, a new rechargeable three‐electrode battery configuration involving lithium, fluorinated graphite, and sulfur electrodes is developed, in which the initial middle‐fluorinated graphite cathode can be electrochemically transformed into a hybrid lithium anode, showing a low overpotential (12 mV), long cycle life (2000 h) and good deep stripping/plating features. This rechargeable battery delivers a high gravimetric energy density of 507.7 Wh kg−1 on the basis of the total mass of the three‐electrode materials. Moreover, the excessive consumption of lithium in the system can be in situ replenished, further lengthening the lifespan.

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