北京航空航天大学王华研究组通过集成无阳极和双离子策略，实现- 40°C下能量密度高的钾金属电池。这一研究成果于2025年1月9日发表在国际顶尖学术期刊《美国化学会杂志》上。

通过无阳极和双离子策略，研究人员在- 40°C下实现了超过400 Wh·kg^-1_{阴极+阳极}的K电池，超过了这些最先进的K电池，甚至超过了大多数低温（LTs）锂/钠电池。通过将强缔合盐作为添加剂引入该无阳极K电池，可以在裸集流器上通过高度可逆的零过量K电镀/剥离行为，建立阴离子衍生的固体电解质界面。

同时，合理设计了二元溶剂，降低了阳离子的脱溶能垒，保证双离子结构中即使在LTs下，也具有相对容易的阳离子和不脱溶阴离子动力学。因此，K||Al半电池在- 40°C下可提供99.98%的高库仑效率。通过与高能阴极配对，制造了一种概念验证的无阳极K双离子电池（N/P = 0），在- 40°C下的能量密度达到407 Wh·kg^-1_{阴极+阳极}，稳定循环183次（80%容量保留）。这项工作为极端情况下的能量密集电池铺平了道路。

由于K⁺的小斯托克斯半径和弱刘易斯酸度，钾(K)基电池在低温应用中具有很大的前景。然而，在零下条件下的高能量密度（>200Wh·kg^-1_{阴极+阳极}）K电池很少有报道。

附：英文原文

Title: Realizing an Energy-Dense Potassium Metal Battery at 40 °C via an Integrated Anode-Free and Dual-Ion Strategy

Author: Jiangchun Chen, Hao Lan, Sicong Wang, Xinyu Liu, Qiaonan Zhu, Xudong Zhang, Mengyao Tang, Shuai Dong, Jie Yang, Mirtemir Kurbanov, Lin Guo, Hua Wang

Issue&Volume: January 9, 2025

Abstract: Potassium (K)-based batteries hold great promise for cryogenic applications owing to the small Stokes radius and weak Lewis acidity of K+. Nevertheless, energy-dense (>200 W h kg–1cathode+anode) K batteries under subzero conditions have seldom been reported. Here, an over 400 W h kg–1cathode+anode K battery is realized at 40 °C via an anode-free and dual-ion strategy, surpassing these state-of-the-art K batteries and even most Li/Na batteries at low temperatures (LTs). By introduction of a strongly associating salt as an additive to this anode-free K battery, an anion-derived solid electrolyte interphase can be established for a highly reversible, zero-excess K plating/stripping behavior on a bare current collector. Meanwhile, a binary solvent is rationally designed for lowering the cation desolvation energy barrier, which ensures comparably facile cation and desolvation-free anion kinetics in this dual-ion structure even at LTs. Consequently, the K||Al half-cell delivers a high Coulombic efficiency of 99.98% at 40 °C. By pairing with a high-energy cathode, a proof-of-concept anode-free K dual-ion battery (N/P = 0) is fabricated, delivering a record-high energy density of 407 W h kg–1cathode+anode with stable cycling of 183 cycles (80% capacity retention) at 40 °C. This work paves a way toward energy-dense batteries at extreme scenarios.

DOI: 10.1021/jacs.4c12126

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.4c12126