Just curious.
If batteries had manufacture dates on them it would be much harder for shady vendors to unload old stock at retail.
Maybe there’s a good reason but it seems it wouldn’t put any extra burden to simply add a date like all food products have.
What say you?
Lithium batteries on a storage charge age really slow
many cells got a QR code, which should include the MFD
You want more rules and regs?
Not at all.
I just want battery manufacturers to wake up tomorrow and say……
“Gee….let’s put dates on all our batteries” 
But I doubt that will happen. If it means putting a burden on them then maybe not. Just wishful thinking because it would help us, the consumer.
Or not
How do we know for sure we’re not getting a 4 or 5 year old battery without it?
It might test ok, but will not last as long.
Unless it’s stamped into the metal can, it’s just as easy to strip the shrinkwrap and put on another, with a new fresher date.
Would be nice if the manufacturer did it voluntarily, or at least coded it, if they didn’t want to print the plain date. Sort of like how some lead acid battery manufacturers use alpha-numeric codes for month of manufacture.
Most batteries I’ve seen that aren’t specifically for industrial use do have a date code of some kind, often month/year.
No I do not want more government regulations.
The name brands like Samsung, LG, Sony, Panasonic Sanyo do have date codes. Anyone’s guess with the re-wrap companies like keeppower, efest, and dozens of others.
For example. this LG HG2. the “P056” stands for February 2016
I like to put my purchase date on batteries when I buy them so down the road I can have an idea of how they did.
Fine tip sharpie usually works for me.
I find the internal resistance a better indicator of battery health.
I like to put the internal resistance on batteries first time I use them so down the road I can have an idea of how they did.
Heaps of my cells have a number stamped on them and inside that number is a date code. I can see what you mean NiMH batteries have a date stamp. I think its because these cells age different.
Because 18650s are no meant for individual sales, this information is not disclosed to the end user, only to the rewrapper or whatever electronic device manufacturer the cell is going to be used in.
Technically we’re not supposed to have bare cells 