Abstract: A negative active material, a method of preparing the negative active material and a lithium ion battery comprising the negative active material are provided. The negative active material may comprise: a core (1) composed of a carbon material; and a plurality of composite materials (2) attached to a surface of the core (1), each of which may comprise a first material (21) and a second material (22) coated on the first material (21), in which the first material (21) may be at least one selected from the elements that may form an alloy with lithium, and the second material (22) may be at least one selected from the group consisting of transition metal oxides, transition metal nitrides and transition metal sulfides.

Abstract: A negative active material, a method for preparing the negative active material and a lithium ion battery comprising the same are provided. The negative active material may comprise: a core, an intermediate layer consisting of a first material and an outmost layer consisting of a second material, which is coated on a surface of the intermediate layer. The first material may be at least one selected from the group consisting of the elements that form alloys with lithium, and the second material may be at least one selected from the group consisting of transition metal oxides, transition metal nitrides and transition metal sulfides.

Abstract: An end cover assembly for a battery with a core comprises a contact terminal, a conductive element, and a thermistor. The conductive element is in electrical communication with the core of the battery. The thermistor is disposed between the terminal and the conductive element. The thermistor electrically connects the terminal and the conductive element when the temperature of the battery is below a predetermined temperature. The thermistor electrically disconnects the terminal and the conductive element when the temperature of the battery is above the predetermined temperature.