20150244030 | LITHIUM ION SECONDARY BATTERY AND ELECTROLYTE SOLUTION THEREOF - The present disclosure provides a lithium ion secondary battery and electrolyte solution thereof. The electrolyte solution of the lithium ion secondary battery includes a nonaqueous organic solvent, and a lithium salt dissolved in the nonaqueous organic solvent. The nonaqueous organic solvent includes a dicyano ester compound of a structure shown by Formula I, Formula II, or Formula III. Formula I represents dicyano carbonate ester compounds, Formula II represents dicyano sulfite ester compounds, Formula III represents dicyano sulfate ester compounds, and the value n is an integer between 1 and 4. The lithium ion secondary battery according to the present disclosure includes the aforementioned electrolyte solution. At a working voltage of 4.3 V or higher, the lithium ion secondary battery according to the present disclosure can effectively suppress the oxidation of the electrolyte solution and improve the storage performance of the lithium ion secondary battery at high temperature. | 08-27-2015 |
20140252267 | SURFACE MODIFIED LITHIUM TITANATE AND PREPARATION METHOD THEREOF - A surface modified lithium titanate and preparation method thereof is provided. In the surface modified lithium titanate, the deactivating groups distributed on the surface of the lithium titanate are —O—P—RR′R″, —O—P—(OR)R′R″, —O—P—(OR)(OR′)R″, and —O—P—(OR)(OR′)(OR″), where R, R′ and R″ are identical or different C1˜C8 alkyl or alkenyl groups. The deactivating groups are bonded to the lithium titanate via a bond or a bridge. The exemplary surface modified lithium titanate can effectively lower its catalytic activity, reduce the gassing of lithium ion batteries, and therefore improve the high temperature storage and high temperature cycle performance of lithium titanate batteries. The exemplary preparation method is simple, has great repeatability, a low cost, low pollution to the environment, and is suitable for industrial production. | 09-11-2014 |