A secondary battery includes a positive electrode, a negative electrode, and an electrolytic solution. The positive electrode includes a lithium-nickel composite oxide. A first O1s spectrum, a second O1s spectrum, a b1s spectrum, a S2p spectrum, a F1s spectrum, and a Ni3p spectrum are detectable by a surface analysis of the positive electrode by X-ray photoelectron spectroscopy. The first O1s spectrum has a peak within a range of binding energy that is greater than or equal to 528 eV and less than or equal to 531 eV. The second O1s spectrum has a peak within a range of binding energy that is greater than 531 eV and less than or equal to 535 eV.

The disclosure discloses an electrolyte and an electrochemical device thereof, and an electronic device. The electrolyte includes a compound represented by formula (I):

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wherein R.sub.1, R.sub.3, and R.sub.4 are each independently selected from hydrogen, a cyano group, a substituted or unsubstituted C.sub.1-12 hydrocarbon group, a substituted or unsubstituted C.sub.1-12 carboxy group, a substituted or unsubstituted C.sub.6-26 aryl group, a substituted or unsubstituted C.sub.2-12 amide group, a substituted or unsubstituted C.sub.0-12 phosphate group, a substituted or unsubstituted C.sub.0-12 sulfonyl group, a substituted or unsubstituted C.sub.0-12 siloxy group or a substituted or unsubstituted C.sub.0-12 boronate group, when being substituted, a substituent includes a halogen atom. The electrolyte of the disclosure may improve the high-temperature cycle performance and room-temperature cycle performance while reducing the internal resistance of the electrochemical device.

Disclosed are a composite solid electrolyte separation membrane using inorganic fiber and a secondary battery using the same, the composite solid electrolyte separation membrane including inorganic fiber, a sodium oxide-based ceramic material impregnated into the inorganic fiber, and an electrolyte impregnated into the inorganic fiber into which the sodium oxide-based ceramic material is impregnated.

An electrolytic solution includes a compound represented by Formula I-A and a compound represented by Formula II-A. In Formula I-A, A.sup.11, A.sup.12, and A.sup.13 are each independently selected from Formula (I-A1) and Formula (I-A2). In Formula I-A, n is a positive integer from 1 to 8. When n>1, the plurality of A.sup.11 structures are identical or different. At least two of the A.sup.11, A.sup.12, or A.sup.13 are selected from I-A2. In Formula II-A, Q is independently selected from Formula (II-A1) and Formula (II-A2). In Formula II-A, m is 1 or 2. R.sup.11, R.sup.12, R.sup.13, R.sup.21, R.sup.22, and R.sup.23 are each independently selected from a covalent single bond, a substituted or unsubstituted C.sub.1 to C.sub.10 alkylidene and heterocyclyl, a substituted or unsubstituted C.sub.2 to C.sub.10 alkenyl and alkynyl, a substituted or unsubstituted C.sub.6 to C.sub.10 aryl, a substituted or unsubstituted C.sub.3 to C.sub.10 alicyclic hydrocarbyl, and a substituted or unsubstituted heteroatom-containing functional group, in which a substituent for substitution is halogen.

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A lithium secondary battery comprising a positive electrode including sulfur, a negative electrode including a Li—Mg alloy, and an electrolyte including a furan-based solvent is provided. The lithium secondary battery has improved lifetime characteristics as growth of lithium dendrites and side reaction between polysulfides leached from the positive electrode and lithium at the negative electrode are suppressed due to interaction of the Li—Mg alloy comprised in the negative electrode and the furan-based solvent comprised in the electrolyte.

A purpose of the present invention is to provide a lithium ion secondary battery in which an increase in internal resistance is suppressed and a halogenated cyclic anhydride is used as an electrolyte additive. The lithium ion secondary battery according to the present invention comprises a positive electrode and an electrolyte solution, wherein a porous layer comprising an insulating filler is formed on the positive electrode, and the electrolyte solution comprises 0.005 to 10 weight % of a halogenated cyclic acid anhydride.

An additive, an electrolyte for a rechargeable lithium battery, and a rechargeable lithium battery, the additive being represented by Chemical Formula 1:

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A secondary battery includes a positive electrode, a negative electrode, and an electrolytic solution. The positive electrode includes a positive electrode active material. The electrolytic solution includes a multi-nitrile compound. The positive electrode active material includes a lithium-nickel composite oxide and a boron compound. The lithium-nickel composite oxide has a layered rock-salt crystal structure. The positive electrode active material has a crystallite size of a (104) plane that is greater than or equal to 40.0 nm and less than or equal to 74.5 nm. The crystallite size is calculated by X-ray diffractometry and Scherrer equation. The positive electrode active material has an element concentration ratio that is greater than or equal to 0.15 and less than or equal to 0.90. The element concentration ratio is calculated on the basis of a B1s spectrum, a Ni2p.sub.3/2 spectrum, a Co2p.sub.3/2 spectrum, a Mn2p.sub.1/2 spectrum, and an Al2s spectrum of the positive electrode active material detected by X-ray photoelectron spectroscopy.

The present disclosure relates to an electrolytic solution for a secondary battery and a lithium secondary battery employing the same. The electrolytic solution for a secondary battery of the present disclosure contains a sulfonyl compound, such that a lithium secondary battery employing a high content of nickel for a cathode has significantly improved quick charge characteristics, room temperature lifespan characteristics, and low-temperature characteristics.

A composition includes a first portion including Ni-rich LiNi.sub.xCo.sub.γMn.sub.zO.sub.2, where 0.5<x<1, 0<y<1, 0<z<1; a second portion including Li.sub.αZr.sub.βO.sub.γ, where 0<α<9, 0<β<3, and 1<γ<10 such that the second portion is coated on the first portion, and the first portion is doped with an elemental metal selected from at least one of Zr, Si, Sn, Nb, Ta, Al, and Fe. A method of forming a composition includes mixing a metal precursor with nickel-cobalt-manganese (NCM) precursor to form a first mixture; adding a lithium-based compound to the first mixture to form a second mixture; and calcining the second mixture at a predetermined temperature for a predetermined time to form the composition.