Real World Considerations Affecting Net Gravimetric and Volumetric Energy Densities in Secondary Lithium Batteries

摘要

Gravimetric and volumetric data are used to compare various secondary cell chemistries and packaging. Unfortunately, the use of either metric will likely over-state the performance of any cell when it is applied in a "real world" application. These metrics apply only to the raw cell, and do not take several necessary components into account, such as protection circuitry (active and passive), internal wiring, protective housings, seals, connectors, internal chargers, output regulators, control circuits, displays, foam padding, adhesive, and additional insulation. These additional components are required for safe operation, interfacing with the host unit, and to provide desired features. While theoretical values of gravimetric density may exceed 200 Wh/kg, and volumetric density can exceed 550 Wh/l, the net values are considerably reduced.