Utilizing an Oxygen-Rich Interface by Hydroxyapatite to Regulate the Linear Diffusion for the Stable Solid-State Electrolytes

Abstract

Improving dissociation and diffusion of lithium ions is the key to solving the practical application of polymer-based solid-state electrolytes (SSE). Here, a low-cost three-dimensional hydroxyapatite (HAP) nanowire is used in polyethene oxide to obtain an enhanced lithium-ion electrolyte. The oxygen-rich interface of HAP provides an integrated dissociation−diffusion platform for lithium salts. The TFSI − anions tend to coordinate with calcium ions, which makes it easier for lithium ions to escape and stay in a free state. The lateral nucleus in the HAP polyethene electrolyte regulates the diffusion from spherical diffusion into linear planar diffusion, which is confirmed by chronoamperometry curves and in situ observation. The stability of the electrolyte at high voltages is improved by inhibiting the superoxide radicals of polyethene oxide chains, which is demonstrated by nuclear magnetic resonance and electron paramagnetic resonance spectroscopy methods. The initial specific charge capacity of the Li/SPE/LiFePO 4 cell with HAP-modified polyethene oxide at 2 C is 148.8 mA h/g, and its initial Coulombic efficiency is 95.17%. After 100 cycles, the specific discharge capacity is 125.5 mA h/g with 99.91% retention per cycle. This oxygen-rich interface strategy would guide the discovery of novel materials for polymer-based SSE.

Spontaneous Desaturation of the Solvation Sheath for High‐Performance Anti‐Freezing Zinc‐Ion Gel‐Electrolyte

“…In addition, Stage 3 is the combination of diffusion and surface reaction control process until the cell system reaches a steady state. [32,33,42] For 1 m ZnSO 4 (Stage 1: 0 ~ t m , Stage 2: t m ~ 44 s, Stage 3: 44 s ~ ∞), the I m is the maximal and the t m is 1.645 s which is the shortest one. It indicates that the interface Zn 2+ transfer is the fastest, and the surface coverage is larger so that there is much more lamellar deposition.…”

Localized gelation cellulose separators enable dendrite-free anodes for future zinc-ion batteries

“…This suggests that the inuence of the LGS on the diffusion process is minor, while being substantially more signicant on the interfacial reaction and the zinc deposition process. 22 The solvation patterns of ZnSO 4 are affected through the direct interaction of cellulose. The two different solvation shells are shown in Fig.…”

An Insight to the Various Applications of Hydroxyapatite

“…HAp facilitated lithium salt dissociation with minor dissociation energy due to the electrostatic attraction between lithium ions and the negative surface charge of HAp. Xi et al [159] incorporated HAp nanowires into PEO SSE and discovered that HAp nanowires could regulate the dissociation and diffusion of lithium ions, and inhibit superoxide radicals in PEO. HAp has been incorporated into the separators of electrochemical cells to confer compositional and structural stability to the separators at high operating temperatures, and to enhance electrochemical performance and cycle stability.…”