If you can help me decode the following manufacturing code on EXIDE EA640 battery, especially

  • which production plant has made it
  • what was the date of manufacturing

    Code: 3EC28K5

Perhaps 28K means November 28 (of which year?), but I'm not sure. The battery was purchased in 2013.

The best will be if you can provide the entire key how to decode these numbers.


I think it is the first two characters 3 for 2013 E for May

I just purchased a similar battery Exide EA770 (March 16) and it is 5MD16B3 - 5M at the start so mine is made in Dec 2015.

Coding would be:


0= 2010






6=2016 etc













M=DEC (L is not used to avoid confusion with the I)


According to this (rather old) article, Exide uses the following code:

  • Forget the first two letters
  • The next three are the letter month (C=March) and day (28) of the month
  • Omit the letter K
  • The last number is the year it was made (5=2005 ... more than likely, depending on the age of the batter - If it looks older, it could be 1995, but that would be way old)

Hope this helps.

  • 2
    I am very sorry Paulster2, I've done about 3+ hours of research by myself and have found this 1987 article among the first. The most suspicious looks to me mfg year. As I wrote, battery was purchased in 2013 and I have certain doubts that the entire EA model series even existed in 2005. Also instead of "skipping letters" as article suggests, I'm interested in mfg plant information. I'm in Europe and I found list where 1st digit 2, 3, 4 denoted 3 different mfg plants in India, so again, not sure here. Need more authoritative source. – miroxlav Jul 5 '15 at 7:41

Depends on what country you buy it in what type of date code they use.

Date code is engraved or hot stamped into the battery case somewhere

This chart is for Automotive, Marine and Motorcycle batteries, but may apply to other types.

Yes they made a mistake on the chart, "explanation" section for Philippines and Korea are swapped

enter image description here

source: http://www.exidebatteries.com.au/battery-faq/

  • Good. There still remains place for confusion because the true date code I posted in the question does not fit the chart. well: EC in the code does not fit MM symbol (until I ignore meaning of either E or C). – miroxlav May 22 '16 at 10:39
  • They change date code formats all the time, for no good reason, then keep the new information secret for other unknown reasons. – Moab May 25 '16 at 14:36

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