Design Principles of Sodium/Potassium Protection Layer for High‐Power High‐Energy Sodium/Potassium‐Metal Batteries in Carbonate Electrolytes: a Case Study of Na₂Te/K₂Te

Abstract

The sodium (potassium)‐metal anodes combine low‐cost, high theoretical capacity, and high energy density, demonstrating promising application in sodium (potassium)‐metal batteries. However, the dendrites’ growth on the surface of Na (K) has impeded their practical application. Herein, density functional theory (DFT) results predict Na2Te/K2Te is beneficial for Na+/K+ transport and can effectively suppress the formation of the dendrites because of low Na+/K+ migration energy barrier and ultrahigh Na+/K+ diffusion coefficient of 3.7 × 10−10 cm2 s−1/1.6 × 10−10 cm2 s−1 (300 K), respectively. Then a Na2Te protection layer is prepared by directly painting the nanosized Te powder onto the sodium‐metal surface. The Na@Na2Te anode can last for 700 h in low‐cost carbonate electrolytes (1 mA cm−2, 1 mAh cm−2), and the corresponding Na3V2 (PO4)3//Na@Na2Te full cell exhibits high energy density of 223 Wh kg−1 at an unprecedented power density of 29687 W kg−1 as well as an ultrahigh capacity retention of 93% after 3000 cycles at 20 C. Besides, the K@K2Te‐based potassium‐metal full battery also demonstrates high power density of 20 577 W kg−1 with energy density of 154 Wh kg−1. This work opens up a new and promising avenue to stabilize sodium (potassium)‐metal anodes with simple and low‐cost interfacial layers.

Highly Potassiophilic Graphdiyne Skeletons Decorated with Cu Quantum Dots Enable Dendrite‐Free Potassium‐Metal Anodes

“…In comparison with the cycling performances of reported K-metal symmetric cells, our system shows conspicuous advantages especially at elevated current densities (Figure 5e; Table S4, Supporting Information). [21,23,[25][26][27][29][30][31]33,34,50,54] Application potentials of the K@NC@GDY-Al was examined as the anode to assemble PMB full cells by using S21-S24, Supporting Information). The first three cycled galvanostatic charge-discharge profiles of the K@NC@GDY-Al||KPB full cell exhibit pronounced voltage platforms in the range of 2.8-3.5 V (vs K + /K) (Figure S25, Supporting Information).…”

“…Despite the appealing features of PMBs, their development has been impeded by a multi tude of obstacles at the anode side thus far, including unstable solid electrolyte interphase (SEI), large volume expansion and uncontrollable growth of K dendrites. [15][16][17][18] To address these challenges, strategic solutions have recently been proposed: (i) modifying the electrolyte to enable a durable SEI layer on the surface of K metal, which is expected to initiate with reversible plating/stripping process; [19][20][21] (ii) engineering the interface between K anode and electrolyte via the creation of artificial coating to inhibit the generation of dendrites; [22][23][24][25][26] (iii) strengthening the interaction between current collector and K anode to homogenize the local current and mitigate the dendritic growth. [27][28][29] To date, the current collectors employed for the anode of alkali metal batteries mainly encompass two types: 3D free-standing supports and commercial Al/Cu foils.…”

Room‐Temperature Sodium–Sulfur Batteries: Rules for Catalyst Selection and Electrode Design

“…The excellent electrochemical performance of the Na/ MoN@CNFs exhibit a significant competitiveness compared to that of recently reported Na anodes, as listed in Figure 5c. [46][47][48][49][50][51][52][53][54][55] Adv. Mater.…”

Artificial Heterogeneous Interphase Layer with Boosted Ion Affinity and Diffusion for Na/K‐Metal Batteries

“…[26] Based on these requirements, various artificial protective layers have been constructed to improve the electrochemical performance of NMAs (PMAs), such as a sulfide-rich SEI layer, [27] Na 3 P, [28] Na-Bi, [29] KSb x F y , [30] and K 2 Te. [31] Among them, inorganic protective layers with a high Na + (K + ) conductivity and Young's modulus have improved the cyclic stability of Na-metal and K-metal batteries. However, owing to their limited mechanical strength and sodiophilicity/ potassiophilicity, these interface layers with a single component cannot effectively tolerate Na (K) dendrite growth during the long-term repeated plating/stripping process, particularly in carbonate-based electrolytes (less than 300 h).…”