Mo2C catalyzed low-voltage prelithiation using nano-Li2C2O4 for high-energy lithium-ion batteries

Abstract

Irreversible lithium loss in the initial cycles appreciably reduces the energy density of lithium-ion batteries. Prelithiation is an effective way to compensate for such lithium loss, but current methods suffer from either the instability or low capacity of prelithiation reagents. Lithium oxalate (Li 2 C 2 O 4 ) has shown great potential as a lithiumcompensation material because of its high theoretical capacity (equivalent to lithium metal), low cost, and air stability. However, the practical applications of Li 2 C 2 O 4 are limited by its low electrochemical activity and high critical decomposition voltage. In this study, we performed the prelithiation of a low-voltage cathode by using Mo 2 C catalysis and nano-Li 2 C 2 O 4 . Results show that the Mo 2 C catalyst changes the electron cloud distribution around Li 2 C 2 O 4 and greatly reduces the activation energy, thereby significantly accelerating the lithium release from Li 2 C 2 O 4 . The nano-Li 2 C 2 O 4 prepared by freeze-drying shows accelerated ionic and electronic conduction as well as close contact with Mo 2 C. Benefiting from the synergistic effect, the decomposition potential of Li 2 C 2 O 4 is decreased by 0.5 V with an efficiency close to 100%. The LiCoO 2 ||SiO full cell empowered with the nano-Li 2 C 2 O 4 /Mo 2 C prelithiation composite demonstrates 46.9% higher capacity than the control and thus has great potential for practical applications.

Prelithiation: A Critical Strategy Towards Practical Application of High‐Energy‐Density Batteries

“…Recently, more and more researchers combined Li 2 C 2 O 4 with conductive carbon materials and catalysts to expand the application range of Li 2 C 2 O 4 , such as Li 2 C 2 O 4 /CMK-3 (4.3 V), [40] Li 2 C 2 O 4 /NiO (nanosheet morphology) and Ketjen black (KB) (4.29 V), [178] nano-Li 2 C 2 O 4 /Mo 2 C (4.22 V). [179] It is worth noting that Fan et al [40] The standard of ideal cathode prelithiation. [52,90,[148][149][150] d) The specific capacities of different cathode prelithium additives.…”

“…Recently, more and more researchers combined Li 2 C 2 O 4 with conductive carbon materials and catalysts to expand the application range of Li 2 C 2 O 4 , such as Li 2 C 2 O 4 /CMK‐3 (4.3 V), [ 40 ] Li 2 C 2 O 4 /NiO (nanosheet morphology) and Ketjen black (KB) (4.29 V), [ 178 ] nano‐ Li 2 C 2 O 4 /Mo 2 C (4.22 V). [ 179 ] It is worth noting that Fan et al. [ 40 ] coated the Li 2 C 2 O 4 /CMK‐3 on the commercial separator to fabricate a novel functionalized prelithiation separator (FPS), which was then used in a LFP//graphite full cell.…”

Advancements in Prelithiation Technology: Transforming Batteries from Li‐Shortage to Li‐Rich Systems

“…Reproduced with permission. [ 123 ] Copyright 2022, Springer Nature. e) Schematic illustration of Li 2 C 4 O 4 prelithiation.…”

Li2CO3 Nanocomposites as Cathode Lithium Replenishment Material for High-Energy-Density Li-Ion Batteries

“…In addition, lithium salts of metal oxides like Li 6 CoO 4 , , Li 5 FeO 4 , and Li 2 NiO 2 are not stable in the air and can provide limited active lithium ions, hindering the actual application. Recently, organic lithium salts, such as Li 2 C 2 O 4 , have also been found to be useful as lithium replenishment material. − Despite being stable in air and not repelling the battery system, they have a relatively low irreversible capacity and require more volume to refill the lithium, which has an impact on the energy density of lithium-ion batteries. Compared to the above-mentioned compounds, Li 2 CO 3 is regarded as an attractive cathode lithium replenishment agent because of its high theoretical capacity (up to 724 mAh·g –1 ) and vast abundance .…”