Developing high-power cathodes is crucial to construct next-generation quick-charge batteries for electric transportation and grid applications. However, this mainly relies on nanoengineering strategies at the expense of low scalability and high battery cost. Another option is provided herein to build high-power cathodes by exploiting inexpensive bulk graphite as the active electrode material, where anion intercalation is involved. With the assistance of a strong alginate binder, the disintegration problem of graphite cathodes due to the large volume variation of >130% is well suppressed, making it possible to investigate the intrinsic electrochemical behavior and to elucidate the charge storage kinetics of graphite cathodes. Ultrahigh power capability up to 42.9 kW kg at the energy density of >300 Wh kg (based on graphite mass) and long cycling life over 10 000 cycles are achieved, much higher than those of conventional cathode materials for Li-ion batteries. A self-activating and capacitive anion intercalation into graphite is discovered for the first time, making graphite a new intrinsic intercalation-pseudocapacitance cathode material. The finding highlights the kinetical difference of anion intercalation (as cathode) from cation intercalation (as anode) into graphitic carbon materials, and new high-power energy storage devices will be inspired.

The intrinsic advantages of metallic Zn, like high theoretical capacity (820 mAh g−1), high abundance, low toxicity, and high safety have driven the recent booming development of rechargeable Zn batteries. However, the lack of high‐voltage electrolyte and cathode materials restricts the cell voltage mostly to below 2 V. Moreover, dendrite formation and the poor rechargeability of the Zn anode hinder the long‐term operation of Zn batteries. Here a high‐voltage and durable Zn–graphite battery, which is enabled by a LiPF6‐containing hybrid electrolyte, is reported. The presence of LiPF6 efficiently suppresses the anodic oxidation of Zn electrolyte and leads to a super‐wide electrochemical stability window of 4 V (vs Zn/Zn2+). Both dendrite‐free Zn plating/stripping and reversible dual‐anion intercalation into the graphite cathode are realized in the hybrid electrolyte. The resultant Zn–graphite battery performs stably at a high voltage of 2.8 V with a record midpoint discharge voltage of 2.2 V. After 2000 cycles at a high charge–discharge rate, high capacity retention of 97.5% is achieved with ≈100% Coulombic efficiency.

The high pseudocapacitance contribution in boron-doped graphite sheets for anion storage is demonstrated, and then utilized to fabricate Na-ion hybrid capacitors.

In-plane asymmetric micro-supercapacitors with ultrahigh energy density are rationally constructed using nano-sandwiched metal hexacyanoferrate/graphene hybrid thin films.

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