Li2Se as a Cathode Prelithiation Additive for Lithium-Ion Batteries

Coassembly of Ultrathin Lithium with Dual Lithium-Free Electrodes for Long-Lasting Sulfurized Polyacrylonitrile Batteries

With the rising demand for long-term grid energy storage, there is an increasing need for sustainable alternatives to conventional lithium-ion batteries. Electrode materials composed of earth-abundant elements are appealing, yet their lithiated-state stability hampers direct battery applications. In this paper, we propose for the first time a concept of coassembling ultrathin lithium with both lithium-free cathodes and lithium-free anodes to build high-energy, long-lasting, safe, and low-cost batteries tailored for long-duration energy storage. As a proof-of-concept, we selected sulfurized polyacrylonitrile (SPAN) as the lithium-free cathode and graphite/silicon-carbon (Gra/SiC) as the lithium-free anode, both of which are earth abundant. This newly conceptualized configuration not only successfully prevents overprelithiation but also exhibits superior energy density (293 Wh kg-1 and 363 Wh kg-1, respectively), excellent cycle stability (1,800 cycles), and benefit of low cost and environmental sustainability. This approach fosters new opportunities for the development of lithium-free, earth-abundant electrode batteries, spurring the development of sustainable and recyclable grid energy storage systems.

Prelithiation strategies for enhancing the performance of lithium-ion batteries

During the initial cycling of lithium-ion batteries, the generation of SEI at the electrode-electrolyte interface and the occurrence of irreversible side reactions consume the active lithium, resulting in irreversible loss of volume (ICL), which may also be accompanied by electrode volume changes and structural collapse. Addressing these challenges has become critical, and pre-lithiation with additional lithium has emerged as a key way to improve battery performance. Hence, this review comprehensively analyzes and summarizes the causes of ICL in lithium-ion batteries, and systematically discusses various prelithiation methods and mechanisms of different electrode structures, especially electrodes. Moreover, we discuss the importance of developing effective electrolyte, separator, and binder pre-lithiation technologies to improve ionic conductivity and battery life. The effectiveness of each strategy in improving initial capacity and cycling stability, while addressing compatibility issues and minimizing potential side effects, is evaluated to inform the future development and large-scale application of pre-lithiation technology.

Over-lithiated NCM through Li5FeO4 for high energy silicon-based lithium-ion batteries

Si/C composite material is a promising anode material for next-generation lithium-ion batteries due to its high capacity. However, it also exhibits significant initial capacity loss in a full cell due to the unstable SEI. To compensate for the loss of Li inventory, a pre-lithiation reagent, Li5FeO4 (LFO), is incorporated into the LiNi0.85Co0.12Mn0.03O2 (NCM85E) cathode for electrochemical evaluation. The results show that with the addition of LFO, the initial discharge capacity of SiC950/NCM85E full cells can increase from 151.0 mA h g-1 to 193.4 mA h g-1 by 28.1% with a high cathode loading up to about 20 mg cm-2. After 200 cycles, the specific capacity also increased by 25.1%.

Harmless pre-lithiation via advantageous surface reconstruction in sacrificial cathode additives for lithium-ion batteries

Sacrificial cathode additives have emerged as a tempting strategy to compensate the initial capacity loss (ICL) in Li-ion batteries (LIBs) manufacturing. However, the utilization of sacrificial cathode additives inevitably brings residuals, side reactions, and negative impacts in which relevant researches are still in the early stage. In this study, we conduct a systematic investigation on the effects of employing a nickel-based sacrificial additive, Li2Cu0.1Ni0.9O2 (LCNO), and propose a feasible strategy to achieve advantageous surface reconstruction on LCNO. Specifically, we build a Li5AlO4 (LAO) coating layer on the LCNO through dry ball milling and annealing treatment. This process not only consumes surface residual lithium compounds on LCNO but also demonstrates minimal detrimental effects on its performance. The surface reconstructed LCNO (SR-LCNO) reveals mitigated gas generation and suppressed structure degradation under high working voltage (＞4.1 V), thereby causing negligible negative effects on the cycling capability and rate performance of commercial cathode materials. The full cells containing SR-LCNO deliver significantly improved electrochemical properties, with no observed exacerbation of side reactions. This work awakes the awareness of the prudent utilization of sacrificial cathode additives and provides an effective strategy for harmless pre-lithiation via surface reconstructed sacrificial cathode additives.