A Black Phosphorus–Graphite Composite Anode for Li-/Na-/K-Ion Batteries

Black phosphorus (BP) is a desirable anode material for alkali metal ion storage owing to its high electronic/ionic conductivity and theoretical capacity. In-depth understanding of the redox reactions between BP and the alkali metal ions is key to reveal the potential and limitations of BP, and thus to guide the design of BP-based composites for high-performance alkali metal ion batteries. Comparative studies of the electrochemical reactions of Li⁺, Na⁺, and K⁺ with BP were performed. Ex situ X-ray absorption near-edge spectroscopy combined with theoretical calculation reveal the lowest utilization of BP for K⁺ storage than for Na⁺ and Li⁺, which is ascribed to the highest formation energy and the lowest ion diffusion coefficient of the final potassiation product K₃P, compared with Li₃P and Na₃P. As a result, restricting the formation of K₃P by limiting the discharge voltage achieves a gravimetric capacity of 1300 mAh g⁻¹ which retains at 600 mAh g⁻¹ after 50 cycles at 0.25 A g⁻¹.     

Alkali‐Metal‐Ion‐Functionalized Graphene Oxide as a Superior Anode Material for Sodium‐Ion Batteries

Although graphene oxide (GO) has large interlayer spacing, it is still inappropriate to use it as an anode for sodium‐ion batteries (SIBs) because of the existence of H‐bonding between the layers and ultralow electrical conductivity which impedes the Na⁺ and e^? transformation. To solve these issues, chemical, thermal, and electrochemical procedures are traditionally employed to reduce GO nanosheets. However, these strategies are still unscalable, consume high amounts of energy, and are expensive for practical application. Here, for the first time, we describe the superior Na storage of unreduced GO by a simple and scalable alkali‐metal‐ion (Li⁺, Na⁺, K⁺)‐functionalized process. The various alkali metals ions, connecting with the oxygen on GO, have played different effects on morphology, porosity, degree of disorder, and electrical conductivity, which are crucial for Na‐storage capabilities. Electrochemical tests demonstrated that sodium‐ion‐functionalized GO (GNa) has shown outstanding Na‐storage performance in terms of excellent rate capability and long‐term cycle life (110 mAh g^?1 after 600 cycles at 1 A g^?1) owing to its high BET area, appropriate mesopore, high degree of disorder, and improved electrical conductivity. Theoretical calculations were performed using the generalized gradient approximation (GGA) to further study the Na‐storage capabilities of functionalized GO. These calculations have indicated that the Na?O bond has the lowest binding energy, which is beneficial to insertion/extraction of the sodium ion, hence the GNa has shown the best Na‐storage properties among all comparatives functionalized by other alkali metal ions.     

Safe,Low‐Cost,Fast‐Kinetics and Low‐Strain Inorganic‐Open‐Framework Anode for Potassium‐Ion Batteries

A key challenge for potassium‐ion batteries is to explore low‐cost electrode materials that allow fast and reversible insertion of large‐ionic‐size K⁺. Here, we report an inorganic‐open‐framework anode (KTiOPO₄), which achieves a reversible capacity of up to 102 mAh g^?1 (307 mAh cm^?3), flat voltage plateaus at a safe average potential of 0.82 V (vs. K/K⁺), a long lifespan of over 200 cycles, and K⁺‐transport kinetics ≈10 times faster than those of Na‐superionic conductors. Combined experimental analysis and first‐principles calculations reveal a charge storage mechanism involving biphasic and solid solution reactions and a cell volume change (9.5 %) even smaller than that for Li⁺‐insertion into graphite (≈10 %). KTiOPO₄ exhibits quasi‐3D lattice expansion on K⁺ intercalation, enabling the disintegration of small lattice strain and thus high structural stability. The inorganic open‐frameworks may open a new avenue for exploring low‐cost, stable and fast‐kinetic battery chemistry.     

Safe,Low‐Cost,Fast‐Kinetics and Low‐Strain Inorganic‐Open‐Framework Anode for Potassium‐Ion Batteries

A key challenge for potassium‐ion batteries is to explore low‐cost electrode materials that allow fast and reversible insertion of large‐ionic‐size K⁺. Here, we report an inorganic‐open‐framework anode (KTiOPO₄), which achieves a reversible capacity of up to 102 mAh g^?1 (307 mAh cm^?3), flat voltage plateaus at a safe average potential of 0.82 V (vs. K/K⁺), a long lifespan of over 200 cycles, and K⁺‐transport kinetics ≈10 times faster than those of Na‐superionic conductors. Combined experimental analysis and first‐principles calculations reveal a charge storage mechanism involving biphasic and solid solution reactions and a cell volume change (9.5 %) even smaller than that for Li⁺‐insertion into graphite (≈10 %). KTiOPO₄ exhibits quasi‐3D lattice expansion on K⁺ intercalation, enabling the disintegration of small lattice strain and thus high structural stability. The inorganic open‐frameworks may open a new avenue for exploring low‐cost, stable and fast‐kinetic battery chemistry.     

MoS2 Nanoflowers with Expanded Interlayers as High‐Performance Anodes for Sodium‐Ion Batteries

MoS₂ nanoflowers with expanded interlayer spacing of the (002) plane were synthesized and used as high‐performance anode in Na‐ion batteries. By controlling the cut‐off voltage to the range of 0.4–3 V, an intercalation mechanism rather than a conversion reaction is taking place. The MoS₂ nanoflower electrode shows high discharge capacities of 350 mAh g^?1 at 0.05 A g^?1, 300 mAh g^?1 at 1 A g^?1, and 195 mAh g^?1 at 10 A g^?1. An initial capacity increase with cycling is caused by peeling off MoS₂ layers, which produces more active sites for Na⁺ storage. The stripping of MoS₂ layers occurring in charge/discharge cycling contributes to the enhanced kinetics and low energy barrier for the intercalation of Na⁺ ions. The electrochemical reaction is mainly controlled by the capacitive process, which facilitates the high‐rate capability. Therefore, MoS₂ nanoflowers with expanded interlayers hold promise for rechargeable Na‐ion batteries.     

Calix[4]pyrrole‐Based Heteroditopic Ion‐Pair Receptor That Displays Anion‐Modulated,Cation‐Binding Behavior

A new ditopic ion‐pair receptor 1 was designed, synthesized, and characterized. Detailed binding studies served to confirm that this receptor binds fluoride and chloride ions (studied as their tetraalkylammonium salts) and forms stable 1:1 complexes in CDCl₃. Treatment of the halide‐ion complexes of 1 with Group I and II metal ions (Li⁺, Na⁺, K⁺, Cs⁺, Mg²⁺, and Ca²⁺; studied as their perchlorate salts in CD₃CN) revealed unique interactions that were found to depend on both the choice of the added cation and the precomplexed anion. In the case of the fluoride complex [ 1? F]^? (preformed as the tetrabutylammonium (TBA⁺) complex), little evidence of interaction with the K⁺ ion was seen. In contrast, when this same complex (i.e., [ 1? F]^? as the TBA⁺ salt) was treated with the Li⁺ or Na⁺ ions, complete decomplexation of the receptor‐bound fluoride ion was observed. In sharp contrast to what was seen with Li⁺, Na⁺, and K⁺, treating complex [ 1? F]^? with the Cs⁺ ion gave rise to a stable, receptor‐bound ion‐pair complex [Cs ?1? F] that contains the Cs⁺ ion complexed within the cup‐like cavity of the calix[4]pyrrole, which in turn was stabilized in its cone conformation. Different complexation behavior was observed in the case of the chloride complex [ 1? Cl]^?. In this case, no appreciable interaction was observed with Na⁺ or K⁺. In addition, treating [ 1? Cl]^? with Li⁺ produces a tightly hydrated dimeric ion‐pair complex [ 1? LiCl(H₂O)]₂ in which two Li⁺ ions are bound to the crown moiety of the two receptors. In analogy to what was seen in the case of [ 1? F]^?, exposure of [ 1? Cl]^? to the Cs⁺ ion gives rise to an ion‐pair complex [Cs ?1? Cl] in which the cation is bound within the cup of the calix[4]pyrrole. Different complexation modes were also observed when the binding of the fluoride ion was studied by using the tetramethylammonium and tetraethylammonium salts.     

Oligoether‐Strapped Calix[4]pyrrole: An Ion‐Pair Receptor Displaying Cation‐Dependent Chloride Anion Transport

A ditopic ion‐pair receptor ( 1 ), which has tunable cation‐ and anion‐binding sites, has been synthesized and characterized. Spectroscopic analyses provide support for the conclusion that receptor 1 binds fluoride and chloride anions strongly and forms stable 1:1 complexes ([ 1? F]^? and [ 1? Cl]^?) with appropriately chosen salts of these anions in acetonitrile. When the anion complexes of 1 were treated with alkali metal ions (Li⁺, Na⁺, K⁺, Cs⁺, as their perchlorate salts), ion‐dependent interactions were observed that were found to depend on both the choice of added cation and the initially complexed anion. In the case of [ 1? F]^?, no appreciable interaction with the K⁺ ion was seen. On the other hand, when this complex was treated with Li⁺ or Na⁺ ions, decomplexation of the bound fluoride anion was observed. In contrast to what was seen with Li⁺, Na⁺, K⁺, treating [ 1?F ]^? with Cs⁺ ions gave rise to a stable, host‐separated ion‐pair complex, [F ?1? Cs], which contains the Cs⁺ ion bound in the cup‐like portion of the calix[4]pyrrole. Different complexation behavior was seen in the case of the chloride complex, [ 1? Cl]^?. Here, no appreciable interaction was observed with Na⁺ or K⁺. In contrast, treating with Li⁺ produces a tight ion‐pair complex, [ 1? Li ? Cl], in which the cation is bound to the crown moiety. In analogy to what was seen for [ 1? F]^?, treatment of [ 1? Cl]^? with Cs⁺ ions gives rise to a host‐separated ion‐pair complex, [Cl ?1? Cs], in which the cation is bound to the cup of the calix[4]pyrrole. As inferred from liposomal model membrane transport studies, system 1 can act as an effective carrier for several chloride anion salts of Group 1 cations, operating through both symport (chloride+cation co‐transport) and antiport (nitrate‐for‐chloride exchange) mechanisms. This transport behavior stands in contrast to what is seen for simple octamethylcalix[4]pyrrole, which acts as an effective carrier for cesium chloride but does not operates through a nitrate‐for‐chloride anion exchange mechanism.     

Transition‐Metal‐Catalyzed Oxidation of Metallic Sn in NiO/SnO2 Nanocomposite

It is well accepted that metallic tin as a discharge (reduction) product of SnO_x cannot be electrochemically oxidized below 3.00 V versus Li⁺/Li⁰ due to the high stability of Li₂O, though a similar oxidation can usually occur for a transition metal formed from the corresponding oxide. In this work, nanosized Ni₂SnO₄ and NiO/SnO₂ nanocomposite were synthesized by coprecipitation reactions and subsequent heat treatment. Owing to the catalytic effect of nanosized metallic nickel, metallic tin can be electrochemically oxidized to SnO₂ below 3.00 V. As a result, the reversible lithium‐storage capacities of the nanocomposite reach 970 mAh g^?1 or above, much higher than the theoretical capacity (ca. 750 mAh g^?1) of SnO₂, NiO, or their composites. These findings extend the well‐known electrochemical conversion reaction to non‐transition‐metal compounds and may have important applications, for example, in constructing high‐capacity electrode materials and efficient catalysts.     

Green Template‐Free Synthesis of Hierarchical Shuttle‐Shaped Mesoporous ZnFe2O4 Microrods with Enhanced Lithium Storage for Advanced Li‐Ion Batteries

In the work, a facile and green two‐step synthetic strategy was purposefully developed to efficiently fabricate hierarchical shuttle‐shaped mesoporous ZnFe₂O₄ microrods (MRs) with a high tap density of ～0.85 g cm³, which were assembled by 1D nanofiber (NF) subunits, and further utilized as a long‐life anode for advanced Li‐ion batteries. The significant role of the mixed solvent of glycerin and water in the formation of such hierarchical mesoporous MRs was systematically investigated. After 488 cycles at a large current rate of 1000 mA g^?1, the resulting ZnFe₂O₄ MRs with high loading of ～1.4 mg per electrode still preserved a reversible capacity as large as ～542 mAh g^?1. Furthermore, an initial charge capacity of ～1150 mAh g^?1 is delivered by the ZnFe₂O₄ anode at 100 mA g^?1, resulting in a high Coulombic efficiency of ～76 % for the first cycle. The superior Li‐storage properties of the as‐obtained ZnFe₂O₄ were rationally associated with its mesoprous micro‐/nanostructures and 1D nanoscaled building blocks, which accelerated the electron transportation, facilitated Li⁺ transfer rate, buffered the large volume variations during repeated discharge/charge processes, and provided rich electrode–electrolyte sur‐/interfaces for efficient lithium storage, particularly at high rates.     

Phosphorus‐Modulation‐Triggered Surface Disorder in Titanium Dioxide Nanocrystals Enables Exceptional Sodium‐Storage Performance

Structural modulation and surface engineering have remarkable advantages for fast and efficient charge storage. Herein, we present a phosphorus modulation strategy which simultaneously realizes surface structural disorder with interior atomic‐level P‐doping to boost the Na⁺ storage kinetics of TiO₂. It is found that the P‐modulated TiO₂ nanocrystals exhibit a favourable electronic structure, and enhanced structural stability, Na⁺ transfer kinetics, as well as surface electrochemical reactivity, resulting in a genuine zero‐strain characteristic with only approximately 0.1 % volume variation during Na⁺ insertion/extraction, and exceptional Na⁺ storage performance including an ultrahigh rate capability of 210 mAh g^?1 at 50 C and a strong long‐term cycling stability without significant capacity decay up to 5000 cycles at 30 C.     

An Ultrastable Anode for Long‐Life Room‐Temperature Sodium‐Ion Batteries

Sodium‐ion batteries are important alternative energy storage devices that have recently come again into focus for the development of large‐scale energy storage devices because sodium is an abundant and low‐cost material. However, the development of electrode materials with long‐term stability has remained a great challenge. A novel negative‐electrode material, a P2‐type layered oxide with the chemical composition Na_2/3Co_1/3Ti_2/3O₂, exhibits outstanding cycle stability (ca. 84.84 % capacity retention for 3000 cycles, very small decrease in the volume (0.046 %) after 500 cycles), good rate capability (ca. 41 % capacity retention at a discharge/charge rate of 10 C), and a usable reversible capacity of about 90 mAh g^?1 with a safe average storage voltage of approximately 0.7 V in the sodium half‐cell. This P2‐type layered oxide is a promising anode material for sodium‐ion batteries with a long cycle life and should greatly promote the development of room‐temperature sodium‐ion batteries.     

Three‐Dimensional Fe2N@C Microspheres Grown on Reduced Graphite Oxide for Lithium‐Ion Batteries and the Li Storage Mechanism

Nanostructured iron compounds as lithium‐ion‐battery anode material have attracted considerable attention with respect to improved electrochemical energy storage and excellent specific capacity, so lots of iron‐based composites have been developed. Herein, a novel composite composed of three‐dimensional Fe₂N@C microspheres grown on reduced graphite oxide (denoted as Fe₂N@C‐RGO) has been synthesized through a simple and effective technique assisted by a hydrothermal and subsequent heating treatment process. As the anode material for lithium‐ion batteries, the synthetic Fe₂N@C‐RGO displayed excellent Li⁺‐ion storage performance with a considerable initial capacity of 847 mAh g^?1, a superior cycle stability (a specific discharge capacity of 760 mAh g^?1 remained after the 100th cycle), and an improved rate‐capability performance compared with those of the pure Fe₂N and Fe₂N‐RGO nanostructures. The good performance should be attributed to the existence of RGO layers that can facilitate to enhance the conductivity and shorten the lithium‐ion diffusion path; in addition, the carbon layer on the surface of Fe₂N can avert the structure decay caused by the volume change during the lithiation/delithiation process. Moreover, in situ X‐ray absorption fine‐structure analysis demonstrated that the excellent performance can be attributed to the lack of any obvious change in the coordination geometry of Fe₂N@C‐RGO during the charge/discharge processes.     

Multiple Active Sites: Lithium Storage Mechanism of Cu‐TCNQ as an Anode Material for Lithium‐Ion Batteries

Recently, carboxylate metal‐organic framework (MOF) materials were reported to perform well as anode materials for lithium‐ion batteries (LIBs); however, the presumed lithium storage mechanism of MOFs is controversial. To gain insight into the mechanism of MOFs as anode materials for LIBs, a self‐supported Cu‐TCNQ (TCNQ: 7,7,8,8‐tetracyanoquinodimethane) film was fabricated via an in situ redox routine, and directly used as electrode for LIBs. The first discharge and charge specific capacities of the self‐supported Cu‐TCNQ electrode are 373.4 and 219.4 mAh g^?1, respectively. After 500 cycles, the reversible specific capacity of Cu‐TCNQ reaches 280.9 mAh g^?1 at a current density of 100 mA g^?1. Mutually validated data reveal that the high capacity is ascribed to the multiple‐electron redox conversion of both metal ions and ligands, as well as the reversible insertion and desertion of Li⁺ ions into the benzene rings of ligands. This work raises the expectation for MOFs as electrode materials of LIBs by utilizing multiple active sites and provides new clues for designing improved electrode materials for LIBs.     

Air‐Stable Lithium Spheres Produced by Electrochemical Plating

Lithium metal is an ideal anode for next‐generation lithium batteries owing to its very high theoretical specific capacity of 3860 mAh g^?1 but very reactive upon exposure to ambient air, rendering it difficult to handle and transport. Air‐stable lithium spheres (ASLSs) were produced by electrochemical plating under CO₂ atmosphere inside an advanced aberration‐corrected environmental transmission electron microscope. The ASLSs exhibit a core–shell structure with a Li core and a Li₂CO₃ shell. In ambient air, the ASLSs do not react with moisture and maintain their core–shell structures. Furthermore, the ASLSs can be used as anodes in lithium‐ion batteries, and they exhibit similar electrochemical behavior to metallic Li, indicating that the surface Li₂CO₃ layer is a good Li⁺ ion conductor. The air stability of the ASLSs is attributed to the surface Li₂CO₃ layer, which is barely soluble in water and does not react with oxygen and nitrogen in air at room temperature, thus passivating the Li core.     

Realizing Complete Solid‐Solution Reaction in High Sodium Content P2‐Type Cathode for High‐Performance Sodium‐Ion Batteries

P2‐type layered oxides suffer from an ordered Na⁺/vacancy arrangement and P2→O2/OP4 phase transitions, leading them to exhibit multiple voltage plateaus upon Na⁺ extraction/insertion. The deficient sodium in the P2‐type cathode easily induces the bad structural stability at deep desodiation states and limited reversible capacity during Na⁺ de/insertion. These drawbacks cause poor rate capability and fast capacity decay in most P2‐type layered oxides. To address these challenges, a novel high sodium content (0.85) and plateau‐free P2‐type cathode‐Na_0.85Li_0.12Ni_0.22Mn_0.66O₂ (P2‐NLNMO) was developed. The complete solid‐solution reaction over a wide voltage range ensures both fast Na⁺ mobility (10^?11 to 10^?10 cm² s^?1) and small volume variation (1.7 %). The high sodium content P2‐NLNMO exhibits a higher reversible capacity of 123.4 mA h g^?1, superior rate capability of 79.3 mA h g^?1 at 20 C, and 85.4 % capacity retention after 500 cycles at 5 C. The sufficient Na and complete solid‐solution reaction are critical to realizing high‐performance P2‐type cathodes for sodium‐ion batteries.     

Lithium‐Rich Layered Oxide Li1.18Ni0.15Co0.15Mn0.52O2 as the Cathode Material for Hybrid Sodium‐Ion Batteries

Li‐rich layered oxide Li_1.18Ni_0.15Co_0.15Mn_0.52O₂ (LNCM) is, for the first time, examined as the positive electrode for hybrid sodium‐ion battery and its Na⁺ storage properties are comprehensively studied in terms of galvanostatic charge–discharge curves, cyclic voltammetry and rate capability. LNCM in the proposed sodium‐ion battery demonstrates good rate capability whose discharge capacity reaches about 90 mA h g^?1 at 10 C rate and excellent cycle stability with specific capacity of about 105 mA h g^?1 for 200 cycles at 5 C rate. Moreover, ex situ ICP‐OES suggests interesting mixed‐ions migration processes: In the initial two cycles, only Li⁺ can intercalate into the LNCM cathode, whereas both Li⁺ and Na⁺ work together as the electrochemical cycles increase. Also the structural evolution of LNCM is examined in terms of ex situ XRD pattern at the end of various charge–discharge scans. The strong insight obtained from this study could be beneficial to the design of new layered cathode materials for future rechargeable sodium‐ion batteries.     

Intermetallic Competition in the Fragmentation of Trimetallic Au–Zn–Alkali Complexes

Cationization is a valuable tool to enable mass spectrometric studies on neutral transition‐metal complexes (e.g., homogenous catalysts). However, knowledge of potential impacts on the molecular structure and catalytic reactivity induced by the cationization is indispensable to extract information about the neutral complex. In this study, we cationize a bimetallic complex [AuZnCl₃] with alkali metal ions (M⁺) and investigate the charged adducts [AuZnCl₃M]⁺ by electrospray ionization mass spectrometry (ESI‐MS). Infrared multiple photon dissociation (IR‐MPD) in combination with density functional theory (DFT) calculations reveal a μ³ binding motif of all alkali ions to the three chlorido ligands. The cationization induces a reorientation of the organic backbone. Collision‐induced dissociation (CID) studies reveal switches of fragmentation channels by the alkali ion and by the CID amplitude. The Li⁺ and Na⁺ adducts prefer the sole loss of ZnCl₂, whereas the K⁺, Rb⁺, and Cs⁺ adducts preferably split off MCl₂ZnCl. Calculated energetics along the fragmentation coordinate profiles allow us to interpret the experimental findings to a level of subtle details. The Zn²⁺ cation wins the competition for the nitrogen coordination sites against K⁺, Rb⁺, and Cs⁺ , but it loses against Li⁺ and Na⁺ in a remarkable deviation from a naive hard and soft acids and bases (HSAB) concept. The computations indicate expulsion of MCl₂ZnCl rather than of MCl and ZnCl₂.     

Micro‐MoS2 with Excellent Reversible Sodium‐Ion Storage

Low storage capacity and poor cycling stability are the main drawbacks of the electrode materials for sodium‐ion (Na‐ion) batteries, due to the large radius of the Na ion. Here we show that micro‐structured molybdenum disulfide (MoS₂) can exhibit high storage capacity and excellent cycling and rate performances as an anode material for Na‐ion batteries by controlling its intercalation depth and optimizing the binder. The former method is to preserve the layered structure of MoS₂, whereas the latter maintains the integrity of the electrode during cycling. A reversible capacity of 90 mAh g^?1 is obtained on a potential plateau feature when less than 0.5 Na per formula unit is intercalated into micro‐MoS₂. The fully discharged electrode with sodium alginate (NaAlg) binder delivers a high reversible capacity of 420 mAh g^?1. Both cells show excellent cycling performance. These findings indicate that metal chalcogenides, for example, MoS₂, can be promising Na‐storage materials if their operation potential range and the binder can be appropriately optimized.     

An O3‐type Oxide with Low Sodium Content as the Phase‐Transition‐Free Anode for Sodium‐Ion Batteries

Layered transition metal oxides Na_xMO₂ (M=transition metal) with P2 or O3 structure have attracted attention in sodium‐ion batteries (NIBs). A universal law is found to distinguish structural competition between P2 and O3 types based on the ratio of interlayer distances of the alkali metal layer d_(O‐Na‐O) and transition‐metal layer d_(O‐M‐O). The ratio of about 1.62 can be used as an indicator. O3‐type Na_0.66Mg_0.34Ti_0.66O₂ oxide is prepared as a stable anode for NIBs, in which the low Na‐content (ca. 0.66) usually undergoes a P2‐type structure with respect to Na_xMO₂. This material delivers an available capacity of about 98 mAh g^?1 within a voltage range of 0.4–2.0 V and exhibits a better cycling stability (ca. 94.2 % of capacity retention after 128 cycles). In situ X‐ray diffraction reveals a single‐phase reaction in the discharge–charge process, which is different from the common phase transitions reported in O3‐type electrodes, ensuring long‐term cycling stability.     

Low‐Temperature Synthesis of Honeycomb CuP2@C in Molten ZnCl2 Salt for High‐Performance Lithium Ion Batteries

Phosphorus‐rich metal phosphides have very high lithium storage capacities, but they are difficult to prepare. A low‐temperature phosphorization method based on Mg reducing PCl₃ in ZnCl₂ molten salt at 300 °C is developed to synthesize phosphorus‐rich CuP₂@C from a Cu‐MOF derived Cu@C composite. Abnormal oxidation of Cu by Zn²⁺ in the molten salt is observed, which leads to the porous honeycomb nanostructure and homogeneously distributed ultrafine CuP₂ nanocrystals. The honeycomb CuP₂@C exhibits excellent lithium storage performance with high reversible capacity (1146 mAh g^?1 at 0.2 A g^?1) and superior cycling stability (720 mAh g^?1 after 600 cycles at 1.0 A g^?1), showing the promising application of P‐rich metal phosphides in lithium ion batteries.