Achieving Desirable Initial Coulombic Efficiencies and Full Capacity Utilization of Li‐Ion Batteries by Chemical Prelithiation of Graphite Anode

Abstract

Chemical prelithiation is an effective approach to elevate the initial Coulombic efficiency (ICE) and energy utilization of Li‐ion battery electrodes. However, this approach fails to operate for the most commonly used graphite (Gr) anode, because all the prelithiation reagents reported so far have a much higher redox potential than Gr (≈0.2 V). Based on ionic solvation and coordination chemistry, for the first time, a new design strategy is proposed for prelithiation solution by selecting a strong electron‐donating, sterically hindered, and chemically stable solvent to tune the redox potential of prelithiation reagent and also to prevent the solvent co‐intercalation during prelithiation process, thus enabling a successful prelithiation of Gr anodes. By theoretical prediction and experimental evaluation, a chemical prelithiation solution, lithium biphenylide/2‐methyl tetrahydrofuran, is successfully developed, which can prelithiate Gr anodes accurately to a desired state in few minutes without destroying the lattice structure of Gr. When the prelithiated Gr anodes (pGr) are paired with the conventional cathodes, the full cells demonstrate significantly improved ICEs and higher energy densities than their counterparts using pristine Gr anodes, showing a great prospect for wide Li‐ion battery applications.

Sodium‐rich NASICON‐structured cathodes for boosting the energy density and lifespan of sodium‐free‐anode sodium metal batteries

“…When the specific power density was 1320 W kg −1 , the Na5VP||Al/C cell maintained a specific energy density of 330 Wh kg −1 . The above results demonstrate that the electrochemical performance of the present Na5VP||Al/C cell is superior to those of other SFA‐SMBs, 27,31,32 Na‐metal batteries, 57 and Na‐ion batteries, 58–60 and is comparable with state‐of‐the‐art LIBs 63,64 . We further fabricated pouch cells to demonstrate the practical feasibility of Na5VP||Al/C cell (Figure Figure S20A).…”

“…The above results demonstrate that the electrochemical performance of the present Na5VPjjAl/C cell is superior to those of other SFA-SMBs, 27,31,32 Na-metal batteries, 57 and Na-ion batteries, [58][59][60] and is comparable with state-of-the-art LIBs. 63,64 We further fabricated pouch cells to demonstrate the practical feasibility of Na5VPjjAl/C cell (Figure Figure S20A). The pouch cell can steadily power a 1.2-meter-long LED strip even under folding and cutting (Figure S20B,C), proving its outstanding flexibility and safety.…”

Porous nanofibers comprising hollow Co 3 O 4 / Fe 3 O 4 nanospheres and nitrogen‐doped carbon derived by Fe@ ZIF ‐67 as anode materials for lithium‐ion batteries

“…However, the pre-lithiation of the electrode material can help efficiently reduce the degree of irreversibility during the first cycle. 47 The Figure 5C exhibits the cycling stabilities of nanofibers at 0.1 A g À1 . A300NF showed excellent cycling performance with a high reversible discharge capacity of 923 mA h g À1 at the 150th cycle.…”

“…The relatively lower CE of A300NF along with A200F compared to A400NF and A500NF could be assigned to the presence of C in large amount with the high initial loss of irreversible capacity in the structure. However, the pre‐lithiation of the electrode material can help efficiently reduce the degree of irreversibility during the first cycle 47 . The Figure 5C exhibits the cycling stabilities of nanofibers at 0.1 A g −1 .…”

A Facile and Efficient Chemical Prelithiation of Graphite for Full Capacity Utilization of Li‐Ion Batteries

“…However, these lithiation solutions are failed to prelithiate Gr anode because their redox potentials are considerably higher than the extremely low formation potential (0.1 V, vs. Li +/ Li) of Li–graphite intercalation compounds (GICs). Recently, our group found it feasible to adjust the redox potential of a lithiation solution down to the formation potential of LiC 6 by selecting an appropriate Li salt and solvent [8e,10] . As a result, we successfully developed a prelithiation solution of lithium biphenylide/2‐methyl tetrahydrofuran (Li‐Biph/2‐Me‐THF), which can prelithiate Gr anode efficiently and controllably in few minutes without damage of the layered structure of Gr.…”