Fluorographites (CFx) are ultrahigh‐energy‐density cathode materials for alkaline‐metal primary batteries. However, they are generally not rechargeable. To elucidate the reaction mechanism of CFx cathodes, in situ transmission electron microscopy characterizations and ab initio calculations are employed. It is found that it is a two‐phase mechanism upon K/Na/Li ion insertion; crystalline KF (crystalline NaF nanoparticles and amorphous LiF) is generated uniformly within the amorphous carbon matrix, retaining an unchanged volume during the discharge process. The diffusivity for K/Na/Li ion migration within the CFx is ≈2.2–2.5 × 10–12, 3.4–5.3 × 10–12 , and 1.8–2.5 × 10–11 cm2 s–1, respectively, which is comparable to the diffusivity of K/Na/Li ions in liquid‐state cells. Encouraged by the in situ transmission electron microscopy (TEM) results, a new rechargeable all‐solid‐state Li/CFx battery is further designed that shows a part of the reversible specific discharge capacity at the 2nd cycle. These findings demonstrate that a solid‐state electrolyte provides a different reaction process compared with a conventional liquid electrolyte, and enables CFx to be partly rechargeable in solid‐state Li batteries.

Nontrivial topological structures offer a rich playground in condensed matters and promise alternative device configurations for post-Moore electronics. While recently a number of polar topologies have been discovered in confined ferroelectric PbTiO3 within artificially engineered PbTiO3/SrTiO3 superlattices, little attention was paid to possible topological polar structures in SrTiO3. Here we successfully create previously unrealized polar antivortices within the SrTiO3 of PbTiO3/SrTiO3 superlattices, accomplished by carefully engineering their thicknesses guided by phase-field simulation. Field- and thermal-induced Kosterlitz–Thouless-like topological phase transitions have also been demonstrated, and it was discovered that the driving force for antivortex formation is electrostatic instead of elastic. This work completes an important missing link in polar topologies, expands the reaches of topological structures, and offers insight into searching and manipulating polar textures.

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