The present invention provides an electrolyte solution for a non-aqueous electrolyte solution battery capable of exhibiting excellent high-temperature cycle characteristics and excellent high-temperature storage characteristics at high temperature of 60° C. or above, and a non-aqueous electrolyte solution battery using the same. The electrolyte solution for a non-aqueous electrolyte solution battery of the present invention comprises at least: a non-aqueous solvent; a solute; at least one first compound represented by the following general formula (1); and at least one second compound represented by the following general formula (2).

##STR00001##

A rechargeable lithium battery includes a compound represented by Chemical Formula 1: ##STR00001##
In Chemical Formula 1, each of k, l, and m is independently an integer of 0 to 20, n is an integer of 1 to 7, and k, l and m are selected such that the compound of Chemical Formula 1 has an asymmetrical structure. The compound of Chemical Formula 1 may be included in the positive electrode, the negative electrode, or the electrolyte of the rechargeable lithium battery.

An electrolyte solution applicable to high-voltage electrochemical devices and capable of improving the cycle characteristics of electrochemical devices even at high voltage, and an electrochemical device. The electrolyte solution contains a fluorinated diether and a metal salt having a specific structure. The fluorinated diether is represented by CFR.sup.11R.sup.12—O—CH.sub.2CH.sub.2—O—R.sup.13, wherein R.sup.11 and R.sup.12 are each individually H, CH.sub.3, F, CH.sub.2F, CHF.sub.2, or CF.sub.3; and R.sup.13 is a C1 or C2 non-fluorinated alkyl group or a C1 or C2 fluorinated alkyl group.

Systems and methods are provided for using electrolytic compositions in lithium ion batteries. In one example, an electrolytic composition may include vinylene carbonate, fluoroethylene carbonate, 1,3-propane sultone, ethylene sulfite, and a conducting salt including no less than 80 mol % of lithium bis(fluorosulfonyl)imide. In this way, a capacity retention of the lithium ion battery may be maintained, such as during high-temperature storage at 100% state of charge.

A lithium secondary battery including a cathode; an anode; and an electrolyte disposed between the cathode and the anode, wherein the cathode includes a cathode active material represented by Formula 1, the electrolyte includes a lithium salt; a non-aqueous solvent; and a monofluorosilane compound represented by Formula 2, wherein an amount of the monofluorosilane compound is in a range of about 0.1 percent by weight (wt %) to about 5 wt % based on the total weight of the electrolyte ##STR00001## wherein, in Formula 1, 0.9≤x≤1.2, 0.85<y≤0.95, and 0≤z<0.2; M is aluminum, magnesium, manganese, cobalt, iron, chromium, vanadium, titanium, copper, boron, calcium, zinc, zirconium, niobium, molybdenum, strontium, antimony, tungsten, bismuth, or a combination thereof; A is an element having an oxidation number of −1 or −2, and R.sub.1 is a substituted or unsubstituted linear or branched C.sub.2-C.sub.30 alkyl group or a substituted or unsubstituted C.sub.6-C.sub.60 aryl group.

An electrolyte capable of lip roving the stability of a lithium-metal battery is provided. The electrolyte includes an organic solvent, a cosolvent, which is different from the organic solvent and includes a fluorine-based compound, and an additive having a lower lowest unoccupied molecular orbital (LUMO) value than the organic solvent.

An electrolyte for a lithium battery and a lithium battery including the same are provided. The electrolyte for a lithium battery may include: a lithium salt; a non-aqueous organic solvent; and an additive including a compound represented by Formula 1.

The present application relates to an electrolytic solution and an electrochemical device using same. The electrolytic solution of the present application comprises a compound containing a —CN functional group and a compound containing a P—O bond. By introducing the compound containing a —CN functional group and the compound containing a P—O bond into the electrolytic solution, an active material can be better protected, thereby effectively improving floatation performance and nailing performance of a battery, and cycle impedance of the battery.

A non-aqueous liquid electrolyte secondary battery using negative-electrode active material having Si, Sn and/or Pb, with high charge-capacity, superior characteristics including discharge-capacity retention rate over long is provided. Its non-aqueous liquid electrolyte contains carbonate having unsaturated bond and/or halogen and compounds like LiPF.sub.6 and/or LiBF.sub.4 (first lithium salt) and lithium salt different from said first one, represented by formula below (second lithium salt).

Li.sub.l(α.sub.mX.sup.a.sub.n) (In the formula, l, m and n represent integers of 1 to 10, 1 to 100 and 1 to 200, respectively. α represents boron, carbon, nitrogen, oxygen or phosphorus. X.sup.a represents functional group having atom selected from 14th to 17th groups of periodic table at its binding-position to α. Two or more of X.sup.a may be connected to each other to form a ring structure. However, such a case where α is boron and X.sup.a is compound represented by

(C.sub.iH.sub.2(i-2)O.sub.4)(C.sub.jH.sub.2(j-2)O.sub.4)

is omitted (i and j represent integers of 2 or larger.)

The present application provides a secondary battery, an electrolyte, and an apparatus including the secondary battery. The secondary battery of the present application includes an electrolyte, characterized in that the electrolyte includes an organic solvent, and the organic solvent includes a cyclic carbonate and a chain carbonate; the mass ratio of the cyclic carbonate and the chain carbonate is from 25:75 to 32:68; the chain carbonate includes dimethyl carbonate; the mass percentage of the dimethyl carbonate in the chain carbonate is greater than or equal to 9 wt % and less than 50 wt %; wherein based on the total mass of the organic solvent, the mass percentage of a carboxylic acid ester is less than 5 wt %. The secondary battery of the present application can simultaneously obtain excellent low-temperature power, long service life and cycle performance.