A Quasi‐Solid‐State Flexible Fiber‐Shaped Li–CO₂ Battery with Low Overpotential and High Energy Efficiency

Abstract

With the rapidly increasing interests on wearable electronics over the past decades, the limited energy density and nondeformable configuration of conventional 2D lithium-ion batteries (LIBs) have already become the dominant obstacles that are hindering the roads of wearable consumer electronics toward ubiquity. [1][2][3][4][5] Hence, it is urgent to develop an alternative highperformance flexible energy storage device to break through the inherent restrictions of rigid LIBs. [6][7][8] The Li-CO 2 battery, a newly conceptual metal-gas battery, has been considered as a promising candidate for the next-generation high-performance electrochemical energy storage system recently. [9,10] It possesses a high theoretical energy density via the four-electrons transfer reaction (4Li + + 3CO 2 + 4e − → 2Li 2 CO 3 + C, E° = 2.80 V vs Li + /Li) and provides a novel environmentally friendly approach to CO 2 fixing which is of great benefit to alleviate global warming. [11][12][13] Interestingly, the Li-CO 2 battery is also very attractive for aerospace exploration; for example, it may be a possible energy system for providing electricity on Mars where the atmosphere consists of 96% CO 2 gas. [14] In spite of the aforementioned favorable factors, very few reports in the literature related to flexible Li-CO 2 battery devices for wearable electronics have been reported so far. After systematical investigations, it is found that the main challenges of fabricating high-performance flexible Li-CO 2 battery devices lie in the following three aspects: (1) carbon nanophases (e.g., Ketjenblack, [9,10,15] CNTs, [11,16] graphene [17,18] ), which dominate those known Li-CO 2 battery catalysts, induce the formation of Li 2 CO 3 , a wide-bandgap insulator. [19,20] It results in a sluggish kinetics for CO 2 evolution so that a high charge potential of 4.2-4.6 V was commonly required to drive the degradation of Li 2 CO 3 in most previous Li-CO 2 batteries. [10,11,17] Such high potential not only increases the risk of electrolyte decomposition but also accelerates the oxidation of electrodes. [21,22] Meanwhile, originated from the incomplete decomposition, more and more solid carbonate species accumulated in the surface of cathode during cycling, leading to a distinct decrease on catalytic performance and even the rapid extension of impedance up to a "sudden death" of the battery. [20,23,24] Consequently, the majority of those reported Li-CO 2 batteries showed a negligibleThe rapid development of wearable electronics requires a revolution of power accessories regarding flexibility and energy density. The Li-CO 2 battery was recently proposed as a novel and promising candidate for nextgeneration energy-storage systems. However, the current Li-CO 2 batteries usually suffer from the difficulties of poor stability, low energy efficiency, and leakage of liquid electrolyte, and few flexible Li-CO 2 batteries for wearable electronics have been reported so far. Herein, a quasi-solidstate flexible fiber-shaped Li-CO 2 battery with low overpotential and ...

Multidimensional Ordered Bifunctional Air Electrode Enables Flash Reactants Shuttling for High‐Energy Flexible Zn‐Air Batteries

“…The C dl was calculated from double-layer charging curves in a non-faradic potential range of 1.1-1.3 V (versus RHE) and using the following equation in which i c and ʋ are charging current (mA cm −2 ) and scan rate (mV s −1 ), respectively [6][7][8][9][10] : The electrocatalytic performances for ORR and OER reactions were measured in a three-electrode cell at standard temperature and pressure conditions.…”

“…[1][2][3][4][5][6][7] Particularly, Znair batteries (ZABs) with superiorities of high theoretical energy density (1218 Wh kg −1 ), low cost, and high safety possess remarkable potential to meet the increasing practical requirements of flexible and wearable electronics. [1][2][3][4][5][6][7] Particularly, Znair batteries (ZABs) with superiorities of high theoretical energy density (1218 Wh kg −1 ), low cost, and high safety possess remarkable potential to meet the increasing practical requirements of flexible and wearable electronics.…”

Reversible Hybrid Aqueous Li−CO2 Batteries with High Energy Density and Formic Acid Production

“…80 %). [22] Also, its theoretical energy density was far higher than aqueous ZnÀCO 2 batteries and comparable with organic Li(Na)ÀCO 2 batteries (Table S1). Therefore, the reversible hybrid aqueous LiÀCO 2 battery had highenergy conversion and storagep erformance that matcheda nd even exceeded organic LiÀCO 2 batteries and aqueous ZnÀCO 2 batteries in some instances.…”

Metal–CO2 Batteries at the Crossroad to Practical Energy Storage and CO2 Recycle

“…Accordingly, ultrathin Ir nanosheets fully anchored on the surface of N‐doped carbon nanofibers (Ir NSs‐CNFs) lowered the charge voltage of the Li–CO 2 batteries to only 3.8 V at 100 mA g −1 and increased the stable cyclability over 400 cycles with a cutoff capacity of 1000 mAh g −1 at 500 mA g −1 . After the successful application of Mo 2 C/CNT catalytic cathodes to significantly lower charge voltage, first‐principles computations further revealed that Mo 2 C could bind oxalate more stably, avoiding the formation of carbonate and carbon derived from oxalate disproportionation . The oxalate product had a charge voltage below 3.5 V, and the Li–CO 2 batteries achieved a high energy efficiency of up to 80% and stable cyclability over 40 cycles at 80 µA cm −2 with 80 µAh cm −2 …”

“…After the successful application of Mo 2 C/CNT catalytic cathodes to significantly lower charge voltage, first‐principles computations further revealed that Mo 2 C could bind oxalate more stably, avoiding the formation of carbonate and carbon derived from oxalate disproportionation . The oxalate product had a charge voltage below 3.5 V, and the Li–CO 2 batteries achieved a high energy efficiency of up to 80% and stable cyclability over 40 cycles at 80 µA cm −2 with 80 µAh cm −2 …”