BATTERY CELL ENGINEERING AND DESIGN TO REACH HIGH ENERGY

摘要

Improved high energy capacity designs for lithium ion batteries are described that take advantage of the properties of high specific capacity anode active compositions and high specific capacity cathode active compositions. In particular, specific electrode designs provide for achieving very high energy densities. Furthermore, the complex behavior of the active materials is used advantageously in a radical electrode balancing design that significantly reduced wasted electrode capacity in either electrode when cycling under realistic conditions of moderate to high discharge rates and/or over a reduced depth of discharge.

主权项

1. A lithium ion secondary battery comprising a positive electrode, a negative electrode, and a separator between the positive electrode and the negative electrode,
wherein the negative electrode comprises a high capacity negative electrode active material with a specific capacity of at least 700 mAh/g at a discharge rate of C/3, has a density in the range of about 0.4 g/mL to about 1.3 g/mL, and has a loading level of negative electrode active material that is at least 1.5 mg/cm2, and wherein the battery has a discharge energy density at the 50th charge-discharge cycle of at least about 250 Wh/kg at C/3 when discharged from 4.5V to 1.5V.