How old is my battery?

[mordoch]

Hi there!
About 10 month ago i bought a "new" battery for my 600x from ebay. A few weeks ago i noticed, that it's capacity goes down rapidly. Now it 'collapses' at about 50-60% downto 4%(!!!).

Now I'd like to know how old the battery was when i bought it. That might explain everythin.
There's a barcode with this number beneath: 1Z2JF680015
And there is FRU 12P4064 and ASM 12P4065.
Is there a way to find out how old it is? Or do I have to open it to have a look at the cells?

Did I perhaps treat it wrong? I love to keep my 600x in stand-by mode. Or shouldn't I do that?

Grz, mordoch

[sktn77a]

I don't think you can rely on e-bay as a source of unused, recently manufactured batteries (define new). Unfortunately, the 600 series battery had a questionable design and you never know if failure is because it's a bad battery or because it's an old battery