Liquid Ammonia Chemical Lithiation: An Approach for High-Energy and High-Voltage Si–Graphite|Li_1+xNi_0.5Mn_1.5O₄ Li-Ion Batteries

Abstract

Chemical lithiation using lithium metal dissolved in liquid ammonia is introduced for the first time as a viable, potentially scalable method to overlithiate cathode materials, in this case, the 5 V spinel Li1+x Ni0.5Mn1.5O4. In this formula the value of x represents the amount of extra lithium inserted into the spinel. Such overlithiated cathodes can subsequently be used to prelithiate high-energy anodes in a lithium-ion battery configuration during the first charge step. Lithiated 5 V spinel Li1+x Ni0.5Mn1.5O4 cathode materials prepared by this technique show higher first delithiation capacities, confirming the chemically inserted lithium is electrochemically active. Full cells with a Si–graphite anode and the Li1+x Ni0.5Mn1.5O4 (x = 0.62) cathode show a 23% higher reversible capacity in the first cycle than LiNi0.5Mn1.5O4 baseline cells and improved capacity retention. The extra chemically inserted lithium therefore sacrificially compensates for the loss of lithium at the anode, allowing higher utilization of the cathode capacity in following cycles.

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

“…[ 87 ] In addition, the liquid ammonia is introduced to dissolve the lithium metal during the prelithiation process. [ 88 ] This method is viable and even scalable to overlithiate cathode materials. In this case, a lithiated 5 V spinel Li 1+ x Ni 0.5 Mn 1.5 O 4 cathode materials have been successfully prepared, showing relatively high first delithiation capacities.…”

“…Considering the highly reactive nature of Li/Na metal, the detailed experiments must be operated in inert environments with H 2 O <0.1 ppm and O 2 <0.1 ppm. Interestingly, a polymer layer (e.g., poly(methyl methacrylate)) can be selected to protect the lithium against Regeneration of battery [171] Thermal lithiation Sn Compensation of irreversible capacity loss [86] Thermal lithiation Si Preparation of prelithiated surface oxide layer [159] High-energy ball-milling with Li Si Compensation of irreversible capacity loss [87] Chemical lithiation with liquid NH 3 LiNi 0.5 Mn 1.5 O 4 Compensation of irreversible capacity loss [88] Chemical lithiation…”

“…[87] In addition, the liquid ammonia is introduced to dissolve the lithium metal during the prelithiation process. [88] This method is viable and even scalable to overlithiate cathode materials. In this case, a lithi- In conclusion, the concept of operation of Li/Na metal based on various approaches could enable the accomplishment of prelithiation/presodiation.…”

Promises and Challenges of the Practical Implementation of Prelithiation in Lithium‐Ion Batteries

“…All gravimetric capacities were extracted from the related literatures. [8,24,27,[37][38][39]56,[58][59][60][63][64][65][66]69,71,98] www.advancedsciencenews.com of Si-carbon nanotubes electrodes was successfully realized by directly dropping 3% SLMPs/toluene solution onto the electrode followed by thermal evaporation to remove the residual toluene (Figure 3a). [52] However, such operation process is not compatible with slurry fabrication process in current battery industry, since SLMPs possess high reactivity with solvents such as water and NMP for slurry, and the powder state of SLMPs poses serious safety concern during their application.…”

“…All gravimetric capacities were extracted from the related literatures. [ 8,24,27,37–39,56,58–60,63–66,69,71,98 ]…”