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High-voltage cathodes paired with lithium metal anode have aroused extensive interests owing to their application potentials for high-density energy storage. Nevertheless, conventional electrolytes fail to maintain the stability of high-voltage cathodes and Li anode, due to their rigid interfacial chemistry with low adsorption of transition metal and strong bonding with Li+ ions. These inadequate interactions exacerbate issues such as transition metal dissolution and non-uniform Li+ transference, ultimately resulting in low cyclability of high-voltage lithium metal batteries (HVLMBs). By incorporating fluoroethylene carbonate (FEC) into lithium bis(trifluoromethane sulfonyl) imide (LiTFSI)/tetramethylene sulfone (TMS) solution, we design a sulfone-based electrolyte to improve the cyclability of HVLMBs with bi-electrode affinity characteristic—the TMS solvent with outstanding anti-oxidation stability preferentially tends to the aggressive cathodes while the FEC solvent with excellent film-forming ability approaches to the Li anode, attributed to the different adsorption energy between various solvents and electrodes. In addition, the sulfone electrolyte forms ultra-thin fluorine and sulfur-rich interphases, containing LiSO2F with S=O bonds of low electron density, associated with Li+ and e− species attacking the S-C and S-N bonds of LiTFSI and the S-C bonds of TMS. As confirmed by in-situ Raman, Ab initio molecular dynamics, and phase field simulations, the LiSO2F uniformizes in-plane Li+ transfer and mitigates transition metal dissolution, owing to the smallest Li+-LiSO2F bonding value (-1.95 eV) and the largest transition metal absorption value with LiSO2F (-3.86 eV) ever reported in the interfacial components. With Coulombic efficiency of 99.3%, the electrolyte enables an 86.1% retention after 500 cycles for Li/NMC811 (4.40 V) batteries.

Ideal separators of Li-ion batteries should possess key characteristics simultaneously, including high mechanical strength, high thermal stability and high electrolyte wettability. Herein a composite separator is proposed to realize these properties by directly incorporating ethyl cyanoacrylate (ECA) into a polyvinylidene fluoride (PVDF) polymer matrix. With significantly enhanced mechanical strength resulting from abundant hydrogen bonds in ECA and van der Waals forces between ECA and PVDF, the ECA–PVDF separator possesses high thermal tolerance and superior capability for electrolyte uptake. The half cell with a LiFePO4 cathode and ECA–PVDF composite separator delivers a high discharge capacity of 154.1 mA h g−1 with 98.4% capacity retention after 100 cycles at 1C (1C = 0.22 mA cm−2), which is attributed to the inherent structure of ECA that exhibits strong interaction with ethylene carbonate (EC), diethyl carbonate (DEC) and ethyl methyl carbonate (EMC).

Incorporation of ceramic materials into separators has been frequently applied in both research and industry to improve the overall high-temperature performances of lithium ion batteries. However, inorganic ceramic particles tend to form aggregation in separators and even fall off in the separator matrix due to the inferior combination between ceramic particles and polymer matrix, giving rise to a decrease in separator porosity and thus the degradation of battery performances. Herein, a single-layer core-shell architecture is designed to reinforce the polymer matrix through encircling Al

Lithium metal batteries (LMBs) have aroused extensive interest in the field of energy storage owing to the ultrahigh anode capacity. However, strong solvation of Li

The lithium sulfur battery is regarded as a potential next-generation high-energy battery system. However, polysulfides dissolve and shuttle through the electrolytes, causing rapid capacity decay, serious self-discharge, and poor high-temperature performances. Here, we demonstrate that by directly introducing glutamate into commercial electrolytes, these issues can be tackled simultaneously. With abundant negatively charged hydroxyl groups, the glutamate additive electrolyte effectively suppresses the shuttling of negatively charged polysulfide ions through strong repulsive interaction up to 1.54 eV. With glutamate additive electrolyte, the lithium sulfur battery has a capacity retention of 60% after 1000 cycles at 5.95 mA/cm2, a self-discharge rate on the order of one-third that of commercial electrolytes, and stable operation at 60 °C.

Lithium ion batteries have profound impact on every corner of human life. However, strong solvation of Li+ and rough interfacial ion transfer associated with conventional electrolytes limit the long cycle, high-rate battery operation of lithium ion batteries. Herein we design an electrolyte system based on fluoroalkyl ether 2,2,2-trifluoroethyl-1,1,2,3,3,3-hexafluoropropyl ether (THE) and ether electrolytes to effectively upgrade the long-cycle rate performances of electrodes in general. With THE rich in fluoroalkyl groups adjacent to oxygen atoms, the electrolyte owns an ultra-high polarity, enabling solvation-free Li+ transfer with an energy barrier of 0.11 eV, only 1/7 of that for conventional ether electrolytes, and 10-times enhancement in Li+ transference at electrolyte/anode interface. In addition, the uniform adsorption of fluorine-rich THE on anode and subsequent LiF formation suppress dendrite formation and stabilize the solid electrolyte interphase layer. With the electrolyte, LiFePO4 cathodes deliver unprecedented cyclic performances with only 0.0012% capacity loss cycle-1 over 5000 cycles at 10 C, along with upgraded rate performances as observed for other mainstream electrodes including LiCoO2, LiNi0.5Mn0.3Co0.2O2 and Li4Ti5O12.

The decent flexibility and processability of solid-state polymer electrolytes (SPEs) endow them with broad development prospects in the solid-state lithium-based batteries field. Nevertheless, the poor room-temperature ionic conductivity of SPEs severely hinders their practical applications. Herein, we design a functionalized poly (vinylidene fluoride) (PVDF)-based electrolyte, and an ionic conductivity elevation is achieved by directly introducing zeolitic imidazolate framework-90 (ZIF-90) as filler into SPE. The metal ion sites of ZIF-90 can adsorb TFSI− with a large adsorption energy of −1.35 eV to facilitate the dissociation of LiTFSI. The SPE modified with ZIF-90 delivers the prominent ionic conductivity of 0.62 mS cm−1 at 30 °C and the low activation energy of 0.20 eV. Simultaneously, cells fabricated with LiFePO4 cathode exhibit the high specific discharge capacity of 118 mAh g−1 after 300 cycles at 1 C (0.44 mA cm−2) at room temperature. This work provides an efficient and promising strategy of fabricating competitive SPEs for solid-state lithium-based batteries.

As a key component of next-generation high-safety lithium batteries, solid-state electrolytes (SSE) have attracted extensive attention. Polyethylene oxide (PEO)-based solid polymer electrolytes exhibit outstanding flexibility and excellent electrode-electrolyte interfaces in comparison with that of inorganic solid electrolytes. Unfortunately, the practical applications of PEO-based solid polymer electrolytes are severely limited by the low ionic conductivity arising from the sluggish segment movement of PEO crystal phase. Herein, an SSE design is presented, which leverages the good flexibility of PEO and enhances its ionic conductivity by directly introducing hydroxyapatite (HAP) as filler into solid polymer electrolyte. With negative potential vacancies of surface, HAP filler can facilitate lithium salt dissociation with a minor dissociation energy of −0.76 eV by attracting Li +. A remarkable ionic conductivity of 0.064 mS cm−1 and a Li+ transference number of 0.366 at 30 °C are achieved. In addition, LiFePO4 (LFP)-Li cell with HAP-modified polymer SSE also delivers a capacity of 118 mAh g−1 after 500 cycles at 1 C at 30 °C, which confirms the practical operability of novel SSE and the validity of HAP filler for SSE enhancement.