Anti-fluorite Li₆CoO₄as an alternative lithium source for lithium ion capacitors: an experimental and first principles study

Abstract

As a promising hybrid energy storage system, lithium ion capacitors (LICs) have been intensively investigated regarding their practical use in various applications, ranging from portable electronics to grid support. The asymmetric LIC offers high-energy and high-power densities compared with conventional energy storage systems such as electrochemical double-layer capacitors (EDLCs) and lithium ion batteries (LIBs). To enable suitable operation of the LIC, the negative electrode should be pre-lithiated prior to cell operation, which is regarded as a key technology for developing self-sustainable LICs. In this work, we have demonstrated the potential use of Li 6 CoO 4 as an alternative lithium source to metallic lithium. A large amount of Li + can be electrochemically extracted from the structure incorporated into the positive electrode via a highly irreversible process. Most of the extracted Li + is available for pre-lithiation of the negative electrode during the first charge. This intriguing electrochemical behaviour of Li 6 CoO 4 is suitable for providing sufficient Li + to the negative electrode. To obtain a fundamental understanding of this system, the electrochemical behaviour and structural stability of Li 6 CoO 4 is thoroughly investigated by means of electrochemical experiments and theoretical validation based on first principles calculations.

DMF stabilized Li3N slurry for manufacturing self-prelithiatable lithium-ion capacitors

“…5c). The highest specific energy and power of 130.1 Wh kg À1 and 5056.9 W kg À1 (based on the total mass of the positive and negative active materials) were achieved for LIC250, which are higher than that of previously reported results [18,20,[40][41][42][43]. The energy characteristic of LIC depends on the non-faradic adsorption/desorption behavior of AC positive electrode.…”

“…Currently, it has been commonly considered as a promising strategy by adding the LSMs in the positive electrode. Many LSMs have been reported, such as Li 2 MoO 3 [16], Li 5 FeO 6 [17], Li 6 CoO 4 [18], Li 2 -RuO 3 [19], Li 5 ReO 6 [20], Li 1Àx Ni 1+x O 2 [21], Li (Ni 1ÀxÀy Mn x Co y )O 2 [22], Co/LiF [23], Li 2 O [24], Co/Li 2 S [25], Li 2 O 2 [26], Co/Li 2 O [27] and Li 3 N [28,29]. Among these materials, Li 3 N has been mostly recognized as a promising alternative, because it owns the highest theoretical specific capacity (2308.5 mAh g À1 ), proper decomposing potential and no residues after decomposition.…”

Prelithiation/Presodiation Techniques for Advanced Electrochemical Energy Storage Systems: Concepts, Applications, and Perspectives

“…A conformal Li 2 O/Co nanoshell (≈20 nm) on LiCoO 2 particles was prepared by in situ chemical formation, which could be selected as a high-capacity built-in prelithiation reagent to compensate this initial lithium loss. [132] Obviously, a capacity of 15 mAh g −1 is increased for the LiCoO 2 with 1.5 wt% In terms of multinary compound, many materials (such as Li 0.65 Ni 1.35 O 2 , [133] Li 2 CuO 2 , [134] Li 2 MoO 3 , [135] Li 5 FeO 4 , [136] Li 6 CoO 4 , [137] NaCrO 2 , [138] and Na 2 NiO 2 [139] ) have been intensively investigated for prelithiation/presodiation in EES systems. Especially, NaCrO 2 material possesses an irreversible phase transition in the high voltage region, delivering an irreversible capacity of up to 230 mAh g −1 .…”

Electrode Materials, Electrolytes, and Challenges in Nonaqueous Lithium‐Ion Capacitors

“…Some prelithiated metal oxides and Li‐rich metal oxides as an alternative lithium source to metallic lithium have been reported. For example, prelithiated Li 3 VO 4 , Li 2 MoO 3 , Li 2 CuO 2 , and anti‐fluorite Li 6 CoO 4 have been studied.…”