You can typically find the car battery's date on the battery case itself, often stamped directly into the plastic or printed on a sticker. The most common locations are on the top of the battery, on the side of the case, or on a small, colored sticker on the end. The date code isn't a simple calendar date; it's a manufacturer-specific alphanumeric code that indicates the month and year of production.
Understanding the code is key. Many brands use a simple letter-number system. The letter corresponds to the month (A for January, B for February, etc.), and the number is the last digit of the year. For example, a code like "C3" would mean the battery was made in March 2023. Other manufacturers use a more complex system that may include a plant code and a Julian date, which is the numerical day of the year.
Here is a quick reference table for common battery brand date codes:
| Battery Brand | Code Format Example | How to Read It |
|---|
| DieHard | D8 | Letter (A-L for Jan-Dec) = Month. Number = Last digit of year (8 = 2018/2028). |
| Duralast | 3BCG3 | First character (number) = Last digit of year (3=2023). Second character (letter) = Month (A=Jan). |
| Optima | 2203 | First two digits = Day of the year (220th day). Last two digits = Year (03 = 2003, 23=2023). |
| Interstate | E3 | Sticker with a letter (A-M, skipping I, for Jan-Dec) and a number for the year (3=2013/2023). |
| EverStart (Walmart) | J2A1 | First letter = Month (A=Jan). First number = Last digit of year (2=2022). |
If the battery is original equipment from the car manufacturer, the date might be harder to find and could be on a sticker attached to the battery rather than molded into the case. Always have a flashlight handy to check in dark engine compartments. Knowing the production date helps you gauge the battery's remaining lifespan, as most have a useful life of 3-5 years.
