A sulfide solid electrolyte, which is able to adjust the morphology unavailable traditionally, or is readily adjusted so as to have a desired morphology, the sulfide solid electrolyte having a volume-based average particle diameter measured by laser diffraction particle size distribution measurement of 3 μm or more and a specific surface area measured by the BET method of 20 m.sup.2/g or more; and a method of treating a sulfide solid electrolyte including the sulfide solid electrolyte being subjected to at least one mechanical treatment selected from disintegration and granulation.

A separator for a lithium secondary battery and a method for manufacturing the same. Particularly, the separator is obtained through immersed phase separation, the content of inorganic particles is controlled to a predetermined level, and a fluorine-based binder polymer is used in combination with a polyvinyl acetate polymer, and thus shows improved heat shrinkage and enhanced adhesion to an electrode.

Battery cells, each including an electrolyte, first and second working electrodes in the electrolyte, and first and second reference electrodes in the electrolyte, are disclosed. The first and second reference electrodes each comprises an active material on a current collector. The active material of the first reference electrode is different from the active material of the second reference electrode.

Disclosed is an electrolyte for a secondary battery, and a secondary battery comprising the same, and in particular, to an electrolyte for a secondary battery including an electrolyte salt, an organic solvent and an additive, wherein the additive includes at least one compound selected from the group consisting of a compound having an N—Si-based bond and a compound having an O—Si-based bond.

A protected anode, an electrochemical device including the same, and a method of preparing the electrochemical device. The protected anode may include: an anode layer; and a protective layer including an oxide represented by Formula 1, on the anode layer:

##STRFormula 1##

In Formula 1, A is at least one of Ge, Sb, Bi, Se, Sn, or Pb; M is at least one of In, Tl, Sb, Bi, S, Se, Te, or Po; A and M are different from each other; and 0<x<100 and 0<y<100.

An anode piece for a lithium battery having both high safety and high capacity, and a preparation method and a use therefor, the anode piece being mixed with a lithium-rich compound, the lithium-rich compound being at least one selected from lithium-rich manganese-based solid solution, a lithium-rich solid electrolyte or a lithium-separated silicon oxide. Li ions can be pulled away from the lithium-rich compound in extreme conditions such as overcharging, internal short circuiting, external short circuiting, thermal abuse, piercing, compressing or overheating, thereby filling in lithium vacancies in the anode material, stabilizing the crystal lattice structure of the anode material, improving safety performance in a battery manufactured by using the material, and allowing the anode piece to maintain excellent cycle performance at higher area capacities.

A unit cell including a thermochromic polymer and a defect detection method using the same are disclosed. Preferably, the unit cell includes a positive electrode, a negative electrode, and a separator disposed between the positive electrode and the negative electrode, wherein the separator includes a thermochromic polymer configured such that the color of the thermochromic polymer changes depending on temperature, whereby the unit cell is easily checked to indicate a short circuit, as well as damage to or defects of the separator.

A method of forming a battery electrode by forming, on a first substrate, a polymer template comprising interconnected polymer fibers, forming, on the polymer template, a carbon coating to form a carbon-coated polymer template, removing the carbon-coated polymer template from the first substrate, subsequent to removing the carbon-coated polymer template from the first substrate, removing the polymer template from the carbon coating, and disposing the carbon coating on a second substrate. A solid electrolyte interphase layer (SEI) comprising the carbon coating produced via the method, a battery electrode comprising such an SEI layer, and a battery comprising such a battery electrode are also provided.

An electrolyte for a lithium secondary battery according to exemplary embodiments may include a lithium salt; a solvent composed of a non-aqueous solvent and including a carbonate solvent; and an additive including a bis(fluorosulfonyl)imide alkali metal salt. Accordingly, it is possible to provide an electrolyte for a lithium secondary battery having excellent high-temperature characteristics, and a lithium secondary battery including the same.

The invention provides a lithium secondary battery including an ionic provider added to the positive electrode and/or a lithium receiver added to the negative electrode. The ionic provider and/or the ionic provider does not involve in the electrochemical reaction of the lithium secondary battery during charging and discharging. The ionic provider can absorb thermal energy caused by the rising temperature of the lithium secondary battery to release the reactive cation. The reactive cation will insert the location with lithium-ion extraction of the positive electrode to make the lattice structure of the positive active material be stable. Therefore, the release of atomic oxygen is avoided. The lithium receiver receives the diffused lithium from the negative electrode to reduce the lithium concentration of the negative electrode. Therefore, it will present a stable state with lower energy to effectively suppress the thermal runaway.