A High Power, Sealed, Lead-Acid Battery for Electric Vehicles

Abstract

A novel, lead-acid battery has been designed specifically for an electric van application. The design consists of horizontally oriented, dual lugged plates in a sealed configuration. Thin plates are used in the design to obtain improved energy performance. High specific power is achieved with dual lugs and a grid aspect ratio that shortens conductor paths. Axial pressure applied to the face of the cell stack allows the thin plates to be used in a deep cycle application. Fifteen cells representing the design concept were fabricated by a battery manufacturer. Twelve of these cells were cycled. The cells attained approximately 600 cycles (80 percent depth of discharge, DOD, at the 2 hour rate) and had not failed before the tests were stopped. The projected specific energy for these cells operated at 110°F (43°C) is about 35 w-hr/kg (2 hr rate). The specific power was calculated to be approximately 200 w/kg (80 percent DOD) when new and 140 w/kg (80 percent DOD) after 364 cycles. The power performance, while still high, did degrade more rapidly than the energy performance.