Development of P3-K_0.69CrO₂ as an ultra-high-performance cathode material for K-ion batteries

Abstract

and exhibited the best cycling performance for a KIB cathode material to date. A combination of electrochemical profiles, ex situ X-ray diffraction, and first-principles calculations was used to understand the overall potassium storage mechanism of P3-K 0.69 CrO 2 . Based on a reversible phase transition, P3-K 0.69 CrO 2 delivers a high discharge capacity of 100 mA h g À1 and exhibits extremely high cycling stability with B65% retention over 1000 cycles at a 1C rate. Moreover, the K-ion hopping into the P3-K 0.69 CrO 2 structure was extremely rapid, resulting in great power capability of up to a 10C rate with a capacity retention of B65% (vs. the capacity at 0.1C).

Sulfonylamide‐Based Ionic Liquids for High‐Voltage Potassium‐Ion Batteries with Honeycomb Layered Cathode Oxides

“…It is evident that few high‐voltage cathodes exist (exhibiting average working voltages of close to or beyond 4 V); Prussian organic moieties and polyanionic compounds such as KVOPO 4 , KVP 2 O 7 , KVPO 4 F, amongst others dominating as high‐voltage cathode candidates. Potassium‐based oxides tend to show low average voltage; however, this prevailing notion was recently obliterated by the design of tellurium‐doped K 2/3 Ni 2/3 Te 1/3 O 2 (or equivalently as K 2 Ni 2 TeO 6 , for simplicity) and K 2/3 Ni 1/3 Co 1/3 Te 1/3 O 2 (K 2 NiCoTeO 6 ) as high‐voltage layered cathode materials (Figure a) . Despite the alluring prospects of using these high‐voltage cathode materials to develop a high‐voltage battery system, instability of organic electrolytes at high‐voltage operation coupled with the high reactivity of potassium metal anode continues to cast doubt on the safety of electrolytes based on organic solvents …”

Structural Insight into Layer Gliding and Lattice Distortion in Layered Manganese Oxide Electrodes for Potassium‐Ion Batteries

“…Current growth rates in lithiumion battery (LIB) manufacturing are not sustainable given our limited lithium resources. [8][9][10][11][12][13][14] Among these, manganese layered oxides are particularly promising due to the high natural abundance and nontoxicity of manganese. [1] Of these, PIBs are more promising due to the closeness of the K + /K redox potential (−2.9 V vs H + /H 2 O) to that of Li + /Li (−3.0 V vs H + /H 2 O), as compared to Na + /Na (−2.7 V vs H + /H 2 O), and the consequential ease of reversible K + intercalation into the most common LIB negative electrode, graphite.…”

Advancements and Challenges in Potassium Ion Batteries: A Comprehensive Review

“…The designing of high‐voltage KIBs are considered to be a challenge due to the limited availability of high‐voltage cathodes and high‐voltage stable electrolytes. In recent years, some cathode materials (K 2/3 Ni 2/3 Te 1/3 O 2 , K 2/3 Ni 1/3 Co 1/3 Te 1/3 O 2 ) have been explored in this aspect . Hence the main challenge is to develop electrolyte which can withstand at high voltages.…”