Building Stable Solid‐State Potassium Metal Batteries

Abstract

Solid‐state potassium metal batteries (SPMBs) are promising candidates for the next generation of energy storage systems for their low cost, safety, and high energy density. However, full SPMBs have not yet been reported due to the K dendrites, interfacial incompatibility, and limited availability of suitable solid‐state electrolytes. Here, we present stable SPMBs using a new iodinated solid polymer electrolyte (ISPE). The functional ions reconstruct ion transport channels, providing efficient potassium ion transport. ISPE shows a combination of high ionic conductivity, superior interfacial compatibility, and electrochemical stability. In‐situ alloying and iodinated interlayer increase K metal compatibility for prolonged cycling with low polarization. Moreover, the ISPE enables SPMBs with Prussian blue cathode stable operation at a high voltage of 4.5 V, a superior rate capability, and long‐term cycling over 3,000 cycles (4.2 V versus K+/K) with an ultra‐high coulombic efficiency of 99.94%. More importantly, a classic solid‐state potassium metal pouch cell achieved 4.2 V stable cycling over 800 cycles with an high retention of 93.6%, presenting a new development strategy for secure and high‐performance rechargeable solid‐state potassium metal batteries.This article is protected by copyright. All rights reserved

Toward Long-Life Lithium Metal Anode by a Li3N-Rich Architecture with Grafted Li Reservoirs

“…However, it should be noted that these metal elements dramatically increase the weight of matrix, which is not friendly for devices in terms of weight energy density. Therefore, developing a 3D matrix with rich N sites for Li in a light mass ratio is quite important. , …”

“…Therefore, developing a 3D matrix with rich N sites for Li in a light mass ratio is quite important. 30,31 Herein, a novel and high N-containing carbon fiber architecture with grafted sphere-like carbon nanotubes (HN-SCNTgCFs) was designed successfully by a two-step route of surface engineering including solid resource assisted chemical…”

Manipulating Interfacial pH by the Base-Catalyzed Hydrolysis Strategy for Highly Reversible Zinc Anodes

“…The pouch cell was fabricated a layer-by-layer structure (anode-separator-cathode) with a length of 5.0 cm and width of 4.0 cm (Figure S19). 47 It is worth mentioning that the fabrication process is likely to affect the performance of the pouch cells. 48 With a high mass loading cathode of ∼8 mg cm −2 , the pouch cells exhibit an initial capacity of 177.5 mA h g −1 at 1 C (Figure 4e) with regular galvanostatic charge/discharge profiles (Figure 4b), and the pouch cells in series can maintain a stable open-circuit voltage and drive a light-emitting diode (LED) sign (Figure 4c).…”

Rational Regulation of High-Voltage Stability in Potassium Layered Oxide Cathodes

“…The high-frequency semicircle corresponds to the electrode–electrolyte interphase process, while the semicircle in the medium-frequency region is mainly attributed to the charge transfer process. The presence of a line is related to the diffusion of the ions within the bulk material. , Notably, significant changes are observed in the charge transfer impedance of pure KMO electrodes during charging and discharging compared to those of the doped sample.…”