Lithium cell with integral annular-shaped ring for reverse polarity protection

摘要

A lithium cell (300) has a can comprising a bottom (335) and a substantially cylindrical sidewall (330) connected to the bottom. The bottom has a recess (400) with a negative terminal (320) centered in the recess. The bottom (335) also includes an annular ring (375) surrounding the recess. The ring and the sidewall (330) are formed as an integral piece from the same material. The recess is of sufficient depth and area such that polarity reversal is prevented if the cell (300) is improperly inserted into a device. The disclosed cell and can designs are particularly suitable for size 123A lithium cells (300).