Gold Peak - 23A Alkaline Batteries - 5 Pack by Gold Peak. $3.26. The shape and aspect ratio of the A23 battery are similar to those of a common AA battery. However, an A23 battery is much smaller than even an AAA battery, measuring only 29 mm long and about 10 mm in diameter, with a typical weight of 8 grams. An A23 battery is a dry cell-type battery mainly used in small electronic key fob devices, such as keyless vehicle entry systems, home security systems, and garage door openers.