How to Check the Date on a Car Battery?
2 Answers
Some battery manufacturers laser-engrave the production date on the side of the battery casing. Some production dates are represented in a six-digit format of day-month-year, while others use a combination of numbers and letters, where the number indicates the last digit of the year and the letter represents the month. However, most batteries have a two-digit production date stamp on the negative terminal, with the top two digits indicating the last digit of the year and the bottom two digits representing the week of production. Below is relevant information about car batteries: 1. A car battery, also known as a storage battery, is a type of battery. Typically, what people refer to as a battery is a lead-acid battery, which is mainly made of lead and its oxides, with sulfuric acid solution as the electrolyte. Batteries are most vulnerable to low temperatures, as their capacity is significantly lower in cold environments compared to normal temperatures. 2. The working principle of a battery is that during discharge, metallic lead acts as the negative electrode, undergoing oxidation to form lead sulfate, while lead dioxide acts as the positive electrode, undergoing reduction to also form lead sulfate. When the battery is charged with direct current, lead and lead dioxide are generated at the respective electrodes. After removing the power source, it returns to its pre-discharge state, forming a chemical battery.
I know this like the back of my hand! Last time I helped a friend inspect a used car, I came across this. Most battery dates are printed on the top or side. For example, Yuasa batteries often have codes like '7C21'—focus on the last two digits, '21' stands for 2021. What does the '7' at the beginning mean? That's July! The letters A, B, C correspond to October, November, December. If you see 'B22', that means it was manufactured in November 2022. Remember, a fresh battery lasts longer. If it's over three years old, be cautious. Even if the date seems recent, check if the electrodes are whitish or oxidized.
