Here’s the three major battery manufacturer’s that make the different brands of battery’s.
When it comes to looking for a replacement battery, the first to check is the date code on the battery. This is a letter followed by numbers. So for example a battery made in January of this year would be an A16 code. And a battery made this month would have a D16 code.
If the battery is more than three months old, it can begin to sulfate from sitting on the shelf. And unless you have access to a battery charger with removes sulfation, don’t expect long battery life.
The next thing to check is the Cold Cranking Amp’s the battery is able to provide. This determines how long the battery will attempt to try to operate the starter at zero degrees. And if there’s a wind chill of -30 degrees, this feature could save your life.
The next to check is the reserve capacity of the battery. This indicates in minutes how long the battery will operate the electrical system in a vehicle if the charging system were to fail. This rating depends on if wipers/headlights are on for the driving conditions. But what reserve capacity is also good for is, for modern vehicles with all the modules/computers that have Keep Alive/Program memories, a higher reserve capacity can prevent the battery from going flat if the vehicle sits for long periods of time.
I learned all this from an engineer I worked with who use to work at Gould Battery.
Tester