Cells or batteries are marked to
indicate polarity of the external connections. Markings may be by symbols such
as "+" and "-," by words, such as "Pos" and "Neg," or by color code (red is
positive). They are also marked to indicate battery type, National Stock
Number (NSN) if appropriate, manufacturer, and date of manufacture. SLI
batteries usually have a letter or number date code to indicate date
(month/year) of manufacture. Safety warnings about the potential hazards of
flammability should be included.
Vent caps are usually inserted into
cell openings in this operation. For dry charged batteries, a barrier strip is
sometimes inserted on the vents or on the caps.