A transversal low-cost pre-metallation strategy enabling ultrafast and stable metal ion capacitor technologies

• Published in: Energy & environmental science Vol. 13; no. 8; pp. 2441 - 2449
• Main Authors: Arnaiz, María, Shanmukaraj, Devaraj, Carriazo, Daniel, Bhattacharjya, Dhrubajyoti, Villaverde, Aitor, Armand, Michel, Ajuria, Jon
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 01.01.2020
• Subjects: Activated carbon; Batteries; Capacitance; Capacitors; Electrodes; Energy storage; Fabrication; Flux density; Lithium; Lithium ions; Low cost; Metal ions; Storage batteries
• ISSN: 1754-5692; 1754-5706
• DOI: 10.1039/d0ee00351d

Metal ion capacitors (MICs) are foreseen to be a complementary alternative of vital importance to current energy storage issues, coupling high energy density delivered by batteries with high power/long cycle life offered by supercapacitors. The prime issues in realising this technology are pre-metallation and replacement of graphite electrodes that bring about an energy gain at the expense of power. Herein we present an easy-to-scale-up approach, combining activated carbon with a highly efficient and industrially compatible low-cost sacrificial salt (dimetal squarates) that can be used as a metal source for pre-metallation. Paired with a hard carbon electrode tailored to perform at high rates, lithium, sodium and potassium MICs are demonstrated. Furthermore, the successful fabrication of a lithium ion capacitor (LIC) pouch cell prototype with high energy at high power densities showing capacitance retention over 84% after 48 000 cycles validates the strategy. This breakthrough may trigger the easy and low-cost fabrication of LICs and significantly reduce technological barriers to market growth and consolidation. A low-cost pre-metallation strategy based on inorganic sacrificial salts that decompose on the first charge.