A Dual‐Ion Battery Constructed with Aluminum Foil Anode and Mesocarbon Microbead Cathode via an Alloying/Intercalation Process in an Ionic Liquid Electrolyte

Abstract

imperative to develop new-generation batteries with high energy densities as well as long cycle lives and good safety. [4][5][6][7][8] These demands trigger intense research leading to various intelligent designs of novel device structures in LIB technology. [9][10][11][12][13][14][15] Dual-ion battery (DIB), typically dualgraphite battery, has been proposed as a novel energy storage device with unconventional architecture which has the merits of high safety and environmental friendliness over conventional LIBs. [16,17] The main difference of working mechanism between DIB and LIB is that both cations (typically Li + ) and anion (such as PF 6 − ) are involved in such DIB for charge transportation and storage, while conventional LIB involves only Li + ion. In 1994, Carlin et al. pioneered the concept of a novel DIB which works via intercalation/ deintercalation of PF 6 − and EMI + at a graphite cathode and a graphite anode, respectively. [18] Consequently, several related works have been reported on DIBs based on different anions, including PF 6 − , BF 4 − , and ClO 4 − , [19][20][21] with high cut-off voltages (4.5-5.2 V vs Li + /Li) and specific capacity up to ≈90 mA h g −1 . [22] For instance, Read et al. reported a dual-graphite battery based on an organic electrolyte containing LiPF 6 , which exhibits a specific capacity of 60 mA h g −1 and a ≈62% capacity retention at C/7 rate after 50 cycles. [22] As these anions intercalate into the graphite cathode typically at potentials up to ≈5 V versus Li + /Li, energy densities of these DIBs are usually higher than those of the conventional LIBs. Generally, most of reported DIBs used carbon materials as cathode, and carbon, [16][17][18][19][20]22] Li, [21] Si, [23] or metal oxide [24][25][26][27] as anode. Recently, we reported a novel DIB using an aluminum foil as anode which also enables the elimination of additional metal current collector and leads to further energy density enhancement and cost saving. [28] However, similar to most of DIBs, its cycling stability is still limited by decomposition of the organic electrolyte due to the high working voltages of DIBs. Additionally, organic solvents in the electrolyte can also cointercalate into the graphite cathode forming Cn + (solv) y X − , [29] resulting in graphite exfoliation upon cycling. Thus, developing appropriate electrolytes with good stability at high voltage is a key challenge for enhancing the cycling stability of DIBs.Ionic liquids (ILs), composed of liquid-state molten salts at room temperature, show good potential in electrochemistry as A novel dual-ion battery constructed with aluminum foil anode and mesocarbon microbead (MCMB) cathode based on a lithium-salt containing ionic liquid electrolyte is prepared. The working mechanism of this Al-MCMB dualion battery is demonstrated to be intercalation/deintercalation of anions into/ from the MCMB cathode and AlLi alloying/dealloying at the Al anode. Owing to the good stability of ionic liquid at high working voltage and the protection of fluoroethylene carb...

A Dual‐Carbon Battery Based on Potassium‐Ion Electrolyte

“…Consequently, novel battery systems such as sodium-ion batteries (SIBs), [3] aluminum-ion batteries (AIBs), [4] and dual-ion batteries (DIBs) [5][6][7][8][9][10][11] characterized by higher abundance and lower cost have attracted extensive attentions. [2] However, the shortage of Li resources, its uneven geographical distribution as well as the growing cost have also become great issues to be solved, which have triggered scientists to investigate renewable alternatives for energy storage.…”

“…[14] However, as the research on KIBs is still at the infancy stage, the mechanisms at an atomic scale and interfaces are unclear. Therefore, developing suitable electrode materials with good performance as well as comprehensively investigating the mechanism are of great importance.On the other hand, another new type of battery called dual-ion battery (DIB) [5][6][7][8][9][10][11] also arouses scientists' concern, which generally consists of dual graphitic carbon electrodes. Therefore, developing suitable electrode materials with good performance as well as comprehensively investigating the mechanism are of great importance.…”

“…are intercalated/deintercalated into graphite anode and graphite cathode, respectively, during the charging/discharging process in the dual-graphite DIB. Consequently, novel battery systems such as sodium-ion batteries (SIBs), [3] aluminum-ion batteries (AIBs), [4] and dual-ion batteries (DIBs) [5][6][7][8][9][10][11] characterized by higher abundance and lower cost have attracted extensive attentions. In addition, the high working voltage (mainly above 4.5 V) [5] of the DIB caused by high anion intercalation potential is also beneficial for high energy density.…”

“…On the other hand, another new type of battery called dual-ion battery (DIB) [5][6][7][8][9][10][11] also arouses scientists' concern, which generally consists of dual graphitic carbon electrodes. Owing to the intrinsic redox amphotericity of graphitic carbon materials, both cations (Li + ) and anions (PF 6 − , BF 4 − , TFSI − , etc.)…”

Low‐Cost Metallic Anode Materials for High Performance Rechargeable Batteries

“…[105] As the ionic liquid electrolyte possesses various merits of negligible vapor pressure, nonflammability, excellent electrochemical stability over a wide voltage window, the Al-graphite DIB based on ionic liquid electrolyte (1.5 m LiTFSI/Pyr 14 TFSI with 10% FEC) showed an improved cycling stability with a reversible capacity of ≈98 mA h g −1 after 300 cycles at 0.5 C with negligible decay. In our recently published work, we prepared a 3D porous Al foil coated with a uniform carbon layer (pAl/C) as the anode in the DIB to significantly improve the cycling life.…”