Disclosed are an electrolyte for lithium secondary batteries including 10 wt % to 90 wt % of an ester based solvent and 10 wt % to 90 wt % of a carbonate based solvent with respect to the total weight of a non-aqueous solvent, and a lithium secondary battery including the same.

The present invention relates to a nonaqueous electrolytic solution for use in a nonaqueous electrolytic solution secondary battery that comprises a negative electrode and a positive electrode capable of storing and releasing metal ions, and a nonaqueous electrolytic solution, wherein the nonaqueous electrolytic solution contains the specific compounds (A) and (B).

Disclosed is a rechargeable lithium battery including a positive electrode including a positive active material; a negative electrode including a negative active material; an electrolyte solution including a lithium salt and a non-aqueous organic solvent; and a separator between the positive and the negative electrodes, the separator including a porous substrate and a coating layer positioned on at least one side of the porous substrate. The negative active material includes a Si-based material; the non-aqueous organic solvent includes cyclic carbonate including ethylene carbonate, propylene carbonate, or combinations thereof, the cyclic carbonate being included in an amount of about 20 volume % to about 60 volume % based on the total amount of the non-aqueous organic solvent; and the coating layer includes a fluorine-based polymer, an inorganic compound, or combinations thereof. The rechargeable lithium battery has improved cycle-life and high temperature storage characteristics.

A secondary battery includes: a cathode, an anode, and an electrolytic solution including a sulfuric acid compound represented by X.sup.n+[M(Rf).sub.a(CN).sub.b(SO.sub.4).sub.c].sup.m−, where X.sup.n+ is an ion such as a metal ion, M is an element such as a transition metal element, Rf is a group such as a fluorine group, a is an integer of 0 to 4, b is an integer of 0 to 5, c is an integer of 1 to 4, m is an integer of 1 to 3, and n is an integer of 1 or 2. The cathode, the anode, and the electrolytic solution are provided inside a film-like outer package member.

Provided is an organic electrolyte solution including a disultone-based compound represented by Formula 1; a first lithium salt that is at least one selected from lithium bis(fluorosulfonyl) imide (Li(FSO.sub.2).sub.2N) and lithium difluorophosphate (LiPO.sub.2F.sub.2); a second lithium salt; and an organic solvent: ##STR00001## wherein, in Formula 1, A.sub.1, A.sub.2, A.sub.3, and A.sub.4 are each independently a C1 to C5 alkylene group unsubstituted or substituted with a substituent; a carbonyl group; or a sulfinyl group, n1 to n4 are each independently 1 to 3, and when the number of A.sub.1, A.sub.2, A.sub.3, and A.sub.4 are each independently two or greater, the plurality of A.sub.1, A.sub.2, A.sub.3, and A.sub.4 are identical to or different from each other.

A DME-free lithium battery includes a positive electrode, a negative electrode, a separator arranged between the positive electrode and the negative electrode, and a liquid electrolyte composed of a solvent and at least one lithium electrolyte salt and with which the electrode and the separator are impregnated, wherein the solvent includes propylene carbonate (PC) as a first solvent component and 1,3-dioxolane (DOL) as a second solvent component, and the positive electrode and/or the negative electrode have a proportion of carbon black having a BET surface area of at least 1 m.sup.2/g.

Described herein are solid-state electrolyte materials having high water content. The electrolyte material may include Li, T, X, A, O, and, optionally, Y, wherein T is at least one element selected from the group consisting of P, As, Si, Ge, Al, and B; X and, when present, Y is a halogen, a pseudohalogen, or a superhalogen; and A is at least one element selected from the group consisting of S, Se, and N. The electrolyte material is made generally by exposing the electrolyte precursors to a predetermined amount of water during manufacturing. Also described herein are methods of making the solid-state electrolyte material, processes for making the solid-state electrolyte material, and electrochemical cells comprising the solid-state electrolyte material.

The invention provides a lithium ion battery comprising: an anode comprising an anode active material layer on an anode current collector, the anode active material layer having a mass load higher than 60 g/m.sup.2; a cathode comprising a cathode active material layer on a cathode current collector, the cathode active material layer having a mass load higher than 80 g/m.sup.2; and an electrolytic solution comprising an imide anion based lithium salt and LiPO.sub.2F.sub.2, wherein at least one of the anode and cathode active material layers comprises a spacer comprising silicone ball.

A secondary battery, includes: a cathode; an anode; and an electrolytic solution including a sulfuric acid compound represented by X.sup.n+[M(Rf).sub.a(CN).sub.b(SO.sub.4).sub.c].sup.m−, where X.sup.n+ is one of ions such as a metal ion, M is one of elements such as transition metal elements, Rf is one of groups such as a fluorine group (—F), a is an integer of 0 to 4, b is an integer of 0 to 5, c is an integer of 1 to 4, m is an integer of 1 to 3, and n is an integer of 1 or 2, where one or more of Rf's are a monovalent fluorinated hydrocarbon group in a case where X=lithium (Li), M=boron (B), a=2, b=0, and c=1 are satisfied.

An electrolyte includes a lithium salt dissolved in a solvent mixture. The solvent mixture may include a first solvent component including an organic solvent having no carbonate groups; a second solvent component configured to improve the electrochemical properties of the first solvent at low temperatures; a third solvent compound configured to promote formation of a passivating SEI layer between the electrolyte and an electrode layer; and a fourth solvent compound configured to stabilize a lithium salt at high temperatures.