Sulfur‐doped hard carbon hybrid anodes with dual lithium‐ion/metal storage bifunctionality for high‐energy‐density lithium‐ion batteries

Abstract

Bifunctional hybrid anodes (BHAs), which are both a high-performance active host material for lithium-ion storage as well as a guiding agent for homogeneous lithium metal nucleation and growth, exhibit significant potential as anodes for next-generation high-energy-density lithium-ion batteries (LIBs). In this study, sulfur-doped hard carbon nanosphere assemblies (S-HCNAs) were prepared through a hydrothermal treatment of a liquid organic precursor, followed by high-temperature thermal annealing with elemental sulfur for application as BHAs for LIBs. In a carbonate-based electrolyte containing fluoroethylene carbonate additive, the S-HCNAs showed high lithium-ion storage capacities in sloping as well as plateau voltage sections, good rate capabilities, and stable cyclabilities.In addition, high average Coulombic efficiencies (CEs) of ~96.9% were achieved for dual lithium-ion and lithium metal storage cycles. In the LIB full-cell tests with typical NCM811 cathodes, the S-HCNA-based BHAs containing ~400 mA h g −1 of excess lithium led to high energy and power densities of ~500 W h kg −1 and ~1695 W kg −1 , respectively, and a stable cycling performance with ~100% CEs was achieved.

An effective model for sodium insertion in hard carbons

“…e p = p 1 (r p )p 2 (N p ) + p 3 (x p ) (19) where e p quantifies the probability of insertion of the first Na into the pore. It has the same form as l 1 (d l ) and varies with the pore radius r p as…”

“…Besides experimental studies, 17–20 there are several theoretical investigations of Na-insertion in HCs. At the atomic level, the simplest models use density functional theory (DFT) to calculate the adsorption energy of Na in a graphite layer with some heteroatoms.…”

“…11 Among several anodes for NIBs, such as MXenes, 3 C 6 B 4 , 12 blue -phosphorene, 13 and 1H-BeP 2 , 14 hard carbon (HC) is a promising anode for NIBs because of stable cycling, large specific capacity, 15 and low-cost biomass product precursors. 15,16 Besides experimental studies, [17][18][19][20] there are several theoretical investigations of Na-insertion in HCs. At the atomic level, the simplest models use density functional theory (DFT) to calculate the adsorption energy of Na in a graphite layer with some heteroatoms.…”

Covalent Organic Framework-Based Materials for Advanced Lithium Metal Batteries

“…14−18 However, the challenges related to LMBs remain substantial, with the primary hurdles being the stability and safety of the battery. 19−21 These concerns are directly connected to the predicament of the lithium anode, which encompasses dendrite formation, 22−24 electrolyte consumption, ineffective use of lithium, 25,26 lithium corrosion, 27,28 and huge anode expansions. 29,30 One of the significant challenges encountered in LMBs is the uncontrolled lithium dendrite growth in the form of sharp needles associated with the thermodynamically unstable interface between lithium metal and electrolyte.…”

“…Lithium–sulfur batteries employing sulfur as the positive electrode can achieve an energy density of 650 W h kg –1 , while lithium–air batteries utilizing oxygen as the positive electrode can reach 950 W h kg –1 . As a result, lithium metal batteries (LMBs) have been widely regarded as a leading contender for the next generation of high energy density energy storage systems. − However, the challenges related to LMBs remain substantial, with the primary hurdles being the stability and safety of the battery. − These concerns are directly connected to the predicament of the lithium anode, which encompasses dendrite formation, − electrolyte consumption, ineffective use of lithium, , lithium corrosion, , and huge anode expansions. , …”