Battery C Rating
In addition to the stated voltage and Ah capacity, SLA batteries have a ‘C’ rating designed to meet specific load applications such as C5, C10 and C20. The vast majority of SLA batteries are rated C20 which means they are designed to provide 1/20th of the stated Ah capacity for 20 hours to 10.5 volts. For example, 7Ah/ C20 = 350mA load for 20 hours. If the ‘C’ rating is not specified consult the battery manufacturer.

Data Code
Manufacturers use different codes to decipher the date of production which is normally stamped on the battery. It is important to decipher this date code for inventory rotation purposes and to ensure you don’t have power supply problems caused by installing old self-discharged stock.

Code Types
Below are three date code examples of premium brand 12 volt/7Ah SLA batteries:
a) Genesis Code 050308G = Mar 8th 2005
b) Power-Sonic Code 02065-L = Jun 2nd 2005
c) Yuasa Code 0603173B = Mar 17th 2006
If you cannot decipher the date code contact the battery manufacturer