Entity

Time filter

Source Type


Patent
Ningbo Institute of Materials Technology, Engineering and Guangdong Keprime Enerstore Ltd | Date: 2012-08-01

Described herein are solid solution composites that are used as cathode materials for lithium-ion batteries. The solid solution composite of LiMVO Also described herein are methods of preparing such composite.


The invention relates to a graphene-modified lithium iron phosphate positive electrode active material and a method for preparing the same, as well as a lithium-ion secondary cell based on this positive electrode active material. The positive electrode active material is prepared by a method in which graphene or graphene oxide and lithium iron phosphate are dispersed in an aqueous solution, agitated and ultrasonicated to mix homogeneously and for a mixture, dried to obtain a lithium iron phosphate material compounded with graphene or graphene oxide, and annealed at high temperature to obtain finally a graphene-modified lithium iron phosphate positive electrode active material. When compared with conventional modified lithium cells coated with carbon or doped with conductive polymers, the lithium-ion secondary cell based on this positive electrode active material features high cell capacity, good cycling performance of charge and discharge, long life and high cycle stability, and has great utility value.


Patent
Ningbo Institute of Materials Technology and Engineering | Date: 2011-11-29

Disclosed are a polylactic acid block copolymer and a preparation method thereof. The polylactic acid block copolymer comprises block A and block B, and is presented as B-b-A-b-B triblock structure, wherein the block A is a cyclic aromatic polyester oligomer block, and the block B is a polylactic acid block. The polylactic acid block copolymer is obtained by ring-opening copolymerization of a cyclic aromatic polyester oligomer and a lactide. Disclosed are another polylactic acid block copolymer and a preparation method thereof. The polylactic acid block copolymer comprises block A and block B, and is presented as B-b-A-b-B triblock structure, wherein the block A is an aromatic polyester block with two hydroxyl end groups, and the block B is a polylactic acid block. The polylactic acid block copolymer is obtained by ring-opening copolymerization of an aromatic polyester with two hydroxyl end groups and a lactide.


Patent
Ningbo Institute of Materials Technology and Engineering | Date: 2011-04-28

The present invention provides a method for preparing graphene, including reacting graphite in an acid solution in which an oxidant is present so as to obtain a graphene. Compared with the prior art, the advantages of the present invention reside in that, the graphene prepared by the method of the present invention has excellent quality and substantially increased yield and production rate, as compared with mechanical stripping, epitaxial growth, and chemical vapor deposition; and the graphene prepared by the method of the present invention has significantly improved quality, substantially reduced structural defects, and significantly increased conductivity, as compared with oxidation-reduction preparation in the solution-phase; besides, the method is also advantageous for a simple process, mild conditions, low cost, and very easy for scale production. The graphene prepared by the present invention has very broad prospects in the fields of lithium-ion batteries, supercapacitors, functional composite materials, transparent conductive films, and microelectronic devices, etc.


Patent
New Energy And Industrial Technology Development Organization, Ningbo Institute of Materials Technology and Engineering | Date: 2011-05-23

Provided is a positive electrode material for a lithium battery with an atomic ratio expressed by the formula (I) Li

Discover hidden collaborations