Recent Advances in Rechargeable Li–CO₂ Batteries

Abstract

Li−CO 2 batteries have attracted increasing attention recently due to their high discharging voltage (∼2.8 V) and large theoretical specific energy (1876 Wh kg −1 ). The conversion of CO 2 relieves its detrimental impact effect on the environment. Despite the aforementioned superiorities, practical Li−CO 2 batteries are still restricted by some issues, such as intricate multiphase interfacial reactions and intrinsic insulating characteristics of carbonate products. Here, reaction mechanisms based on CO 2 conversion reaction are summarized. Updated research achievements about catalytic cathodes and electrolyte systems are reviewed and discussed. Critical scientific issues and innovative perspectives are presented for Li−CO 2 electrochemistry. This review provides an overall recognition for the latest Li− CO 2 system and indicates the potential evolutions for the next-generation energy storage system.

Challenges and prospects of lithium–CO2batteries

“…To fulfill the requirements in different scenarios, various electrolyte candidates have been developed and tested in Li-CO2 batteries, including liquid electrolytes (aqueous or organic-based), solid-state electrolytes (glass, ceramics, and polymers), hybrid electrolytes (liquid + solid), and ionic liquid electrolytes (e.g., 1-ethyl-3-methylimidazolium chloride) [10]. Although a great quantity of studies on Li-CO2 batteries are concentrated on organic-based liquid electrolytes, they still suffer from some intrinsic drawbacks in practical battery systems, such as the possible leakage, evaporation, and flammability for the semiopen cell structure [68]. Among the alternatives, solid-state or quasi-solid-state electrolytes can overcome the aforementioned obstacles and thus enhance the security; however, the large impedance of solid-solid interfaces between electrode and electrolyte leads to a relatively low ion conductivity and should be resolved before practical application.…”

“…The traditional lithium salts generally contain LiBF4, LiClO4, LiTFSI, lithium bis(fluorosulfonyl)imide (LiFSI), LiPF6, LiCF3SO3, etc. [68]. The state-of-the-art LiPF6 salt in Li ion batteries has been excluded in Li-CO2 batteries, however, because it is unstable with the attack of oxygen intermediates generated during redox reactions [73].…”

“…The state-of-the-art LiPF6 salt in Li ion batteries has been excluded in Li-CO2 batteries, however, because it is unstable with the attack of oxygen intermediates generated during redox reactions [73]. Inspired by the successful electrolytes applied in Li-air batteries, the vast majority of electrolytes in Li-CO2 batteries employ relatively limited choices, such as LiTFSI and LiCF3SO3 [68]. Unfortunately, the problem of the poor stability of Li metal in LiTFSI-based electrolyte under CO2 atmosphere remains unsettled, which causes that the conducting lithium salt still represents as one of the bottlenecks in stabilizing the operation of Li-CO2 batteries [74].…”

Carbon Tube-Based Cathode for Li-CO2 Batteries: A Review

“…A typical type of Li-CO 2 battery consists of a porous cathode, electrolyte (liquid, solid), and lithium metal anode [17]. The basic structure is shown in Figure 2, in the form of coin cells from different points of view.…”

Virtual Special Issue of Recent Research Advances in China: Batteries and Energy Storage

“…As an emerging research topic, Li–CO 2 batteries have attracted more attention in recent studies. Sun et al . provide an overall view about the progress of the latest Li–CO 2 system, including the reaction mechanisms, catalytic cathodes, and electrolytes, along with innovative perspectives on future research.…”