A ceramic solid-state electrolyte of lithium aluminum titanium phosphate with the composition of Li[Formula: see text]Al[Formula: see text]Ti[Formula: see text](PO[Formula: see text] (LATP) was synthesized by a sol–gel method using a pre-dissolved Ti-source. The annealed LATP powders were subsequently processed in a binder-free dry forming method and sintered under air for the pellet preparation. Phase purity, density, microstructure as well as ionic conductivity of the specimen were characterized. The highest density (2.77[Formula: see text][Formula: see text] with an ionic conductivity of [Formula: see text] (at 30[Formula: see text]C) was reached at a sintering temperature of 1100[Formula: see text]C. Conductivity of LATP ceramic electrolyte is believed to be significantly affected by both, the AlPO4 secondary phase content and the ceramic electrolyte microstructure. It has been found that with increasing sintering temperature, the secondary-phase content of AlPO4 increased. For sintering temperatures above 1000[Formula: see text]C, the secondary phase has only a minor impact, and the ionic conductivity is predominantly determined by the microstructure of the pellet, i.e. the correlation between density, porosity and particle size. In that respect, it has been demonstrated, that the conductivity increases with increasing particle size in this temperature range and density.

Nanocrystalline LiTi2(PO4)3/C has been synthesized by employing a solvothermal process in which oxalic acid was used as a solubilizer for the titanium source, a surfactant, and a carbon source. Additionally, Pechini's sol–gel‐based method was also used as the synthesis method for comparison. LiTi2(PO4)3/C prepared by using a solvothermal route showed a homogenous particle size with spindle‐like microstructures formed from self‐assembled nanosized‐platelets, whereas preparation by the sol–gel process resulted in agglomerated powders with irregular morphology and particle size. The different morphologies of LiTi2(PO4)3/C prepared in the two synthesis methods tend to form different electrode layer structures, which results in remarkable differences in their electrochemical properties. In particular, the solvothermally synthesized LiTi2(PO4)3/C composite exhibits superior high‐rate‐discharge capability and cycling stability. A capacity of approximately 97.7 % of the initial capacity was maintained for the solvothermal sample after 500 cycles at 5 C.

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High rate capability and long-term cycling spindle-like LiTi 2 (PO 4 ) 3 /C anode and needle-like Li 3 V 2 (PO 4 ) 3 cathode have been evaluated in half-cell, and combined to fabricate an advanced fast cyclable all phosphate lithium-ion battery. The electrode materials with well-defined morphology were prepared by a solvothermal reaction followed by annealing, delivering capacities of 115.0 and 118.1 mAh · g −1 at 25 • C over 200 cycles at 0.5 C, respectively. For the full cell assembly, no prelithiation process is needed for the selected electrode pair due to their mutually matched capacity and stoichiometric amount of lithium-ions. The fabricated full cell, with an output voltage of more than 1.5 V, inherits a superior rate capability and cycling performance of its electrodes. A discharge capacity of 36 mAh · g −1 at 30 C (about 30% of the initial discharge capacity at 0.1 C) and a capacity retention of ∼35% at 5 C over 1000 cycles has been achieved. Furthermore, one of the most important reasons for the capacity fading in the full cell during long-term cycling is found to be a decomposition and structural degradation of Lithium-ion batteries are widely used in portable electronics and are a promising energy storage system for electric vehicles because of their high energy density and long cycle life.1,2 However, current lithium-ion battery technologies are still far from satisfaction to meet the increasingly diverse range of applications. For instance, the use of lithium-ion cells in large scale applications, such as electric vehicles, demands high charge/discharge cycling performance and an inherent high thermal stability.3,4 Micro-lithium-ion batteries which can be applied to human body require in first instance the considerations of safety issue and cycling performance. 5,6 For the development of a novel type of lithium-ion battery like all-solid-state lithium-ion battery, one of the urgent needs to be addressed is to improve the ionic and electronic conductivity among the whole battery system. 7,8 Additionally, high rate performance and long cycle life are required for lithium-ion battery as stationary application for power management. To advance the battery technologies according the desired applications, it is important to explore the cathode and anode materials, and match them reasonably and to investigate their electrochemical performances. [10][11][12] have attracted much attention because more than two formula units of Li-ions can possibly intercalate/deintercalate into/from their host crystal structure during discharge/charge at a moderate working potential. On the basis of the crystal structure in these cathode materials, the use of phosphate polyanions (PO 4 ) 3− is considered as a potential alternative to oxide-based cathodes. The strong P−O bonds and the framework of (PO 4 ) 3− anions can guarantee both the dynamic and thermal stabilities required to fulfill the safety requisites in high-power applications.18 More than that, phosphate materials are also believed to be superior candidates of an...

Potassium-ion batteries (KIBs) are gradually being considered as an alternative for lithium-ion batteries because of their non-negligible advantages such as abundance and low expenditure of K, as well as higher electrochemical potential than another alternativesodium-ion batteries. Nevertheless, when the electrode materials are inserted and extracted with large-sized K + ions, the tremendous volume change will cause the collapse of the microstructures of electrodes and make the charging/discharging process irreversible, thus disapproving their extended application. In response to this, we put forward a feasible strategy to realize the in situ assembly of layered MoSe 2 nanosheets onto N, P codoped hollow carbon nanospheres (MoSe 2 / NP-HCNSs) through thermal annealing and heteroatom doping strategies, and the resulting nanoengineered material can function well as an anode for KIBs. This cleverly designed nanostructure of MoSe 2 /NP-HCNS can broaden the interlayer spacing of MoSe 2 to boost the efficiency of the insertion/extraction of K ions and also can accommodate large volume change-caused mechanical strain, facilitate electrolyte penetration, and prevent the aggregation of MoSe 2 nanosheets. This synthetic method generates abundant defects to increase the amounts of active sites, as well as conductivity. The hierarchical nanostructure can effectively increase the proportion of pseudo-capacitance and promote interfacial electronic transfer and K + diffusion, thus imparting great electrochemical performance. The MoSe 2 /NP-HCNS anode exhibits a high reversible capacity of 239.9 mA h g −1 at 0.1 A g −1 after 200 cycles and an ultralong cycling life of 161.1 mA h g −1 at 1 A g −1 for a long period of 1000 cycles. This nanoengineering method opens up new insights into the development of promising anode materials for KIBs.