It’s a well-known fact that Li-ion batteries have a shelf-life, and the OEM warranty on batteries is typically only a year. This is because not only do the cells degrade over time, but they also degrade over use. If you’re having trouble with your laptop battery, it’s often worth a minute or two to read the date code on it to see if it’s premature failure or old age. You can read more about Li-ion cell life here if you’re interested.
Every Dell part has a PPID sticker, and the Dell part number is part of that number. Along with the country of origin, the date of manufacture, and some other information. I’ll explain three of these fields. Here is a sample PPID sticker from a Dell battery:
You see three fields marked in the photo:
Country of origin: The first field (blue field) in the photo indicates the part’s 2-letter country of origin. In this case, Korea.
Part number: The second field (green field) in the photo has the Dell part number. In this case, UD265 (the leading zero is omitted if present). Knowing the part number makes it easier to order a replacement battery. :)
Date Code: The fourth field (red field) in the photo shows the parts date code in three digits:
The first [hex] digit indicates the year of manufacture. 1-9 for 2001-2009 respectively, 0 for 2010, A for 2011, B for 2012, C for 2013, D for 2014, E for 2015, F for 2016, etc. (Note: See Chris’ comment below.)
The second [hex] digit indicates the month of manufacture. 1-9 for January through September, respectively, and A-C for October through December.
The third [hex] digit indicates the day of manufacture. 1-9 for day 1 through 9 respectively, and A-V for 10-31.
This battery was made January 5th 2008.