Iodine as a Temperature‐Responsive Redox Shuttle Additive for Swelling Suppression of Lithium‐Ion Batteries at Elevated Temperatures

Abstract

The swelling issue by gas evolution at elevated temperatures (85–90 °C) is one of the major challenges related to current Li‐ion batteries (LIBs). We herein demonstrate that iodine (I2) as a redox shuttle additive, when its dose is properly determined, can suppress the swelling behavior of LiCoO2/graphite Al‐pouch cells during storage at 90 °C without sacrificing other cell performances. This approach is based on two findings: 1) swelling during 90 °C storage is severe only when the cells are fully charged, and 2) the shuttling reaction of I2 can be tuned to be activated only when the temperature is as high as 90 °C by employing an appropriate amount of I2. Therefore, when a fully charged cell is exposed to a temperature of 90 °C, the self‐discharge by I2 lowers the state of charge of the cell, suppressing the swelling. This temperature‐responsive shuttling behavior of I2 is ascribed to the preferential adsorption of I2 on the cathode surface. It is also confirmed that inclusion of the I2 additive does not lead to deterioration in other aspects of cell performance, such as the discharge capacity or long‐term cyclability. Along with the improved cell performance, the low‐cost and environmental compatibility of I2 makes it a promising electrolyte additive for thermally robust LIBs.

Halide‐Based Materials and Chemistry for Rechargeable Batteries

“…[70][71][72] Furthermore,s urface modifications including fluorination treatments, [29,73] halide coatings, [74,75] and halide-reinforced chemical adsorption [76,77] were conducted to stabilize the electrode structure and electrode/electrolyte interfaces of intercalation electrodes and conversion electrodes,s uch as sulfur and metal oxides.E lectrode/electrolyte interface modifications could also be achieved by employing fluorinated solvents or electrolytes containing halogens. [7,[78][79][80][81] In addition, fluoropolymers generally have high chemical and electrochemical stabilities,a nd their porous and mechanical properties can be tuned by synthetic methods.I ndeed, some fluoropolymer-based separators have proven to be beneficial for enhancing battery performance.…”

“…[147] Park et al demonstrated that the use of iodine as ar edox shuttle additive suppressed the swelling of the LiCoO 2 /graphite cell during storage at 90 8 8Cwithout the deterioration of other cell properties. [81] Boulineau et al prepared aseries of highly ionconductive Li 6 PS 5 X( X= Cl, Br,I )L i-argyrodites as solidstate electrolytes of LIBs. [148] Li 6 PS 5 Cl with optimized structures showed aconductivity of 1.33 10 À3 Scm À1 at 298 Kand ah igh electrochemical stability of up to 7V(versus Li + /Li).…”

Halogenid‐basierte Materialien und Chemie für wiederaufladbare Batterien

“…Die Anpassungen an die Elektroden/Elektrolyt-Grenzflächen kçnnen auch durch Einsatz von fluorierten Lçsungsmitteln oder Elektrolyten, die Halogene beinhalten, realisiert werden. [7,[78][79][80][81] Außerdem haben Fluorpolymere generell hohe chemische und elektrochemische Stabilitäten und ihre porçsen und mechanischen Eigenschaften kçnnen mit synthetischen Methoden angepasst werden. Einige auf Fluorpolymeren basierenden Separatoren erwiesen sich als vorteilhaft fürdie Steigerung der Batterieleistung.…”

“…[147] Park et al zeigten, dass die Verwendung von Iod als Redox-Shuttle-Additiv die Anschwellung der LiCoO 2 /Graphit-Zelle während der Speicherung bei 90 8 8Cverhinderte,und dabei ohne Verschlechterung anderer Zelleigenschaften. [81] Boulineau et al präparierten eine Reihe von Li 6 PS 5 X-Li-Argyroditen (X = Cl, Br, I) mit hoher Ionenleitfähigkeit als Elektrolyten im Festzustand von LIBs. [148] Das Li 6 PS 5 Cl wies mit optimierten Strukturen eine Leitfähigkeit von bei 298 Ka uf und eine hohe elektrochemische Stabilitätv on bis zu 7V (vs.L i + /Li).…”

A Lithium–Air Battery Stably Working at High Temperature with High Rate Performance

“…The fiber‐shaped lithium–air batteries demonstrated better thermal stability beyond many other kinds of batteries. For lithium‐ion batteries (LIBs), the highest working temperature has been increased to 90 °C by introducing additives to electrolyte, optimizing electrode material, using polymer electrolyte, or adding ionic liquids; for lithium–sulfur (Li–S) batteries, a general strategy was adopted by changing electrode materials, by which they could withstand a peak temperature of 70 °C. In the case of lithium–oxygen (Li–O 2 ) batteries, polymer electrolyte was employed to obtain a flexible battery and increased the working temperatures to 80 °C.…”