Introducing KI as a functional electrolyte additive to stabilize Li metal anode

A low cost Zn2+/I− redox active electrolyte for a high energy and long cycle-life zinc hybrid battery–capacitor

“…At a lower KI concentration (0.04 M), the smaller number of K + ions limited the possibility to effectively suppress the formation of dendrites at the anode. 53 In contrast, the reduced number of I − ions in 0.04 M KI resulted in reduced redox activity, thus reducing the specific capacity (Fig. S10e and f†).…”

“…Consequently, the synergetic effect in the KI-containing AZHBC enabled its high capacity compared to the ZnI 2 -containing AZHBC. 53 Furthermore, the reason behind the 3-step redox reaction step for KI-included electrolyte compared to just 2-step reactions for ZnI 2 -included electrolyte is not completely clear. One of the possible reasons can be as follows: the lower ionization energy of I − in KI (due to K + being a single-charge carrier) compared to that in ZnI 2 (due to the di-valence of Zn 2+ ).…”

Enabling uniform Li deposition behavior with dynamic electrostatic shield by the single effect of potassium cation additive for dendrite-free lithium metal batteries

“…Among the selected alkaline cations, the K + cation additives are more attractive than Rb + or Cs + cation-containing additives, when considering the production cost and low environmental impact. 29–35…”

“…Among the selected alkaline cations, the K + cation additives are more attractive than Rb + or Cs + cation-containing additives, when considering the production cost and low environmental impact. [29][30][31][32][33][34][35] K + has been introduced as an electrostatic shielding cation in several previous studies, using compounds such as KPF 6 , KNO 3 , KPBS, and KI. Tu et al recently reported that a trace amount of KPF 6 additive (0.01 M) in a LiTFSI/ether-based electrolyte showed long-term cyclability as a synergistic effect.…”

“…K + can help adjust the electrochemical deposition of Li + , whereas I À can rapidly recover inactive lithium due to iodine redox. 34 Although various strategies have been proposed, to the best of our knowledge, the previously reported papers have changed both the types of anions and cations, while little attention has been paid to the cation effect. Based on the described prior work, we used KTFSI as an electrolyte additive in lithium metal batteries for the first time.…”