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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.

Advanced electrolytes play a key role in the development of next-generation lithium secondary batteries. However, many strong polar solvents, as a major component of the electrolyte, are incompatible with the commercialized graphite anode in Li-ion batteries. In this work, we propose a new concept of the coordination number (CN) rule to tune electrochemical compatibility of electrolytes by regulating the ion–solvent-coordinated (ISC) structure. Based on this rule, we introduced the low-coordination-number solvents (LCNSs) into the high-coordination-number solvent (HCNS) electrolytes to induce anions into the first solvation shell of Li+, forming the anion-induced ISC (AI-ISC) structure. The HCNS-LCNS electrolytes with the AI-ISC structure show enhanced reduction stability, enabling reversible lithiation/delithiation of the graphite anode. Infrared analysis and theoretical calculations confirm the working mechanism of the electrochemical compatibility in the HCNS-LCNS electrolytes based on the CN rule. Therefore, the CN rule provides guidance for the design of highly stable and multifunctional electrolytes to develop next-generation lithium secondary batteries.

Propylene carbonate (PC) ‐based electrolytes have many desirable advantageous properties compared to the currently used ethylene carbonate (EC) ‐based electrolytes for lithium ion batteries, however, their poor compatibility with the graphite anode hinders its applications. Here, a facile and effective strategy to make electrochemically compatible PC‐based electrolytes by use of a weakly coordinating diethyl carbonate co‐solvent to induce PF6− anions into the solvation shell of Li+ to form an anion‐induced ion–solvent‐coordinated (AI‐ISC) structure is reported. Such an AI‐ISC structure can lead to an increase of the lowest unoccupied molecular orbital energy level of the electrolyte, therefore considerably improving the reduction tolerance of the PC solvent. Furthermore, by using the film‐forming additive (fluoroethylene carbonate, FEC), an electrochemically stable, EC‐free PC‐based electrolyte, which enables reversible Li+ intercalation on the graphite electrode is obtained. The graphite/LiNi0.5Mn0.3Co0.2O2 pouch cells using this PC‐based electrolyte exhibit very similar room‐temperature electrochemical performance to those using conventional EC‐based electrolytes and excellent low‐temperature performance. This work provides a new approach to make EC‐free electrolytes with a similar AI‐ISC structure but without the need for a high concentration of Li salt of highly concentrated electrolytes, which may bring new insights in the development of advanced electrolyte systems for wide battery applications.

Many organic solvents have very desirable solution properties such as wide temperature range, high solubility of Li salts, and nonflammability, should be able but fail in reality to serve as...

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