US 2003/0113636 A1 · Lithium secondary battery

Abstract

A lithium secondary battery comprising positive and negative electrodes both capable of occluding and releasing lithium ions, and a lithium ion conductive material which contains a compound of formula (1) exhibits improved characteristics including charge/discharge efficiency, low-temperature properties and cycle performance when (a) only one substituent group of R1, R2, R3 and R4 in formula (1) is alkyl, (b) the negative electrode-constituting material partially contains a carboxyl or hydroxyl group-bearing compound, and the lithium ion conductive material contains propylene carbonate, or (c) a positive electrode active material is a lithium-containing transition metal compound, a negative electrode active material is a carbonaceous material, and the lithium ion conductive material contains as a non-aqueous electrolysis solution a solvent mixture of propylene carbonate and ethylene carbonate in combination with a chain-like carbonate as a low-viscosity solvent. 1

Claims28

Dependent claims

A lithium secondary battery comprising a positive electrode and a negative electrode both capable of occluding and releasing lithium ions, and a lithium ion conductive material,

the lithium ion conductive material containing propylene carbonate and a compound of the following formula (1):
7
wherein n is an integer of 0 or 1, each of R1, R2, R3 and R4 is hydrogen or an alkyl group of 1 to 5 carbon atoms,
the propylene carbonate accounting for more than 50% by volume of entire solvent components.

1 more element

A lithium secondary battery comprising a positive electrode and a negative electrode both capable of occluding and releasing lithium ions, and a lithium ion conductive material,

the lithium ion conductive material containing a compound of the following formula (1):
8
wherein n is an integer of 0 or 1, R1, R2, R3 and R4 each are hydrogen or an alkyl group of 1 to 5 carbon atoms,
wherein either one of the following requirements (a), (b) and (c) is met,
(a) in formula (1), only one of the substituent groups represented by R1, R2, R3 and R4 is alkyl,
(b) the material of which the negative electrode is made comprises a carboxyl or hydroxyl group-bearing compound as a portion thereof, and said lithium ion conductive material contains propylene carbonate,
(c) a positive electrode active material is a lithium-containing transition metal compound, a negative electrode active material is a carbon material, and said lithium ion conductive material contains as a non-aqueous electrolysis solution a solvent mixture of propylene carbonate and ethylene carbonate in combination with a chain-like carbonate as a low-viscosity solvent.

4 more elements

Dependencies are inferred from the claim text.

Lithium secondary battery

Life of this patent

Lithium secondary battery

Life of this patent

Abstract

Claims28