Lithium Ion Battery shelf Life

[kurutta]

I found someone on craigslist selling 6-cell batteries for the T60 that are "new in a sealed Lenovo factory box". This sounded fine, but I understand that suppliers of Lithium-Ion batteries, remove batteries from sale after a certain time period. So I was suspicious that the batteries being offered had been surplussed and were old enough to have significantly less capacity then a new battery.

The seller admitted that the batteries were somewhat dated, but did not come up with the date they were manufactured. He also stated that all the packages he opened contained batteries that were "fully discharged".

I have some questions:

(1) How quickly does a new Lithium-Ion battery loose capacity as it sits "on the shelf"?

(2) How quickly does a new Lithium-Ion battery self discharge?

(3) What does Lenovo consider the shelf life to be?

(4) What does it mean if a new unused battery is found to be fully discharged?

I have limited experience with Lithium-Ion batteries. All that I have are used, so I have never experience one that is new. Any help from experienced folks would be appreciated.

[EOMtp]

Each of your questions can be answered with "It depends!" Read the following for a perspective:
http://batteryuniversity.com/learn/arti ... _batteries

In a batch like the one you describe, one is likely to find batteries which are anywhere from totally dead to fully functional. No way to know without testing each battery. The highest likelihood is that the batteries are fairly close to "new" status ... although that probability can be, e.g., 50% and still be the "highest" likelihood! In other words, the highest likelihood does not necessarily imply a high likelihood.

[slpin]

in my experience buying old batteries that are "new" and havent been charged and sat in box, they usually all get full capacity....

[ajkula66]

For T60 batteries, the single most important factor is the manufacturer.

If they're Panasonic, buy without fear.

If they're Sony or Sanyo, haggle away.

Run the FRU number against the ones listed in HMM and you might get lucky with an answer.

Overall, I had very good experiences with genuine NOS batteries. YMMV.

[kurutta]

Thanks all, for the help with the battery questions.

The main problem I am having is that the seller is not into specifying exactly what he is selling. When I asked for the date of manufacture he did not answer. But he states:

I have no idea why they were sold, but you're probably right, and that they are dated by now. They're original Lenovo though, and I haven't had any complaints from people. They are sealed, and do not have a charge on them (from the few I've opened). I have no idea how far they could have come down from 5200mah, but they are working, otherwise I'm sure I would have had complaints.

From here, I'm not really going to go into much more detail. I'm not going to open them up, find a T60 and run the battery maximizer and sit there with u for 3 hours while it charges, etc... Some people are just crazy. They work, I'm confident of that, they're sealed... if u want one, let me know ur number and we can set a time for u to come get one. U can come to my house, so that also tells u how confident I am that they're not crap.

He is selling them on craigslist. The problem for me is that I live in Seattle and the seller is in the SF bay area. This means I have to get my brother to drive over and buy it for me and I only want to do that if I have a good idea of what is being sold. This fellow may be a very good source of 6-cell batteries. He is asking $45.

I don't think the label on the carton lists the FRU number. Only the part number and the serial number.

[dr_st]

Reiterating what was said:

For T60 batteries, the single most important factor is the manufacturer.

If they're Panasonic, buy without fear.

If they're Sony or Sanyo, haggle away.

The guy can check the FRU printed on the battery (which will tell you the manufacturer) without having to test them.