Molecularly Compensated Pre‐metallation Strategy for Metal‐ion Battery and Capacitor

Sacrificial cathode additive as a pre-metallation method could ensure adequate metal sources for advanced energy storage devices. However, this pre-metallation technique is seriously suffered from the precise regulation of decomposition potential of additive. Herein, a molecularly compensated pre-metallation (Li/Na/K) strategy has been successfully achieved through Kolbe electrolysis, in which the electrochemical oxidation potential of metal carboxylate is manipulated by the bonding energy of oxygen-metal (O-M) moiety. As theoretically predicted, the electron-donating effect of substituent and low charge density of cation can dramatically weaken the O-M bond strength, further bringing out the reduced potential. Thus, sodium acetate exhibits a superior pre-sodiation feature for sodium-ion battery accompanied with a large irreversible specific capacity of 301.8 mAh g -1 , remarkably delivering 70. 6% enhanced capacity retention after 100 cycles. Notably, this elaborate methodology has been profoundly extended to construct high-performance lithium-ion battery and lithium/sodium/potassium-ion capacitor. This breakthrough has paved an innovative pathway for pre-metallation enabled by organic electrochemistry, offering in-depth insights into directional design of sacrificial reagent for electrochemical energy storage systems.