OT...Lithium-ion battery inherent defect?
Interesting "fact" found mentioned in passing in an electric car article in "Switching Power Magazine" Vol 6 Issue 1 2005.
Paraphrased, it went as follows:
"lithium-ion batteries ... have an aging problem, however, about which most manufacturers keep understandably quiet. After a year, some degradation is noticeable, regardless of whether or not you use the battery. After 2-3 years, the battery fails."
I have to say that I have not (yet) noticed it in my camera batteries, although in computer batteries, I found that the battery may be expensive (and unreturnable) junk as soon as purchased.
I don't think that my comnputer battery experience is directly what was meant in the article, but it may be the same process. If that battery had been sitting a while, it could be old enough to fail purely from age and not use, as mentioned.
The magazine is a fairly reputable technical journal, and not given to "internet legends", so I have to take the comment somewhat seriously.
Anyone know more about this?
That corresponds with what I have heard about L-ion batteries. It isn't exactly news though. It's known as poor "calendar life". There are improvements happening on that issue.
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I had a li-ion battery apparently last about 10 years in a PLC memory backup situation. I say "aparently" because I was going by the scribbled note on the case that had the last change date. It's always possible it was changed somewhere in between that time frame and the second time the changer didn't write a note about it. It was a small 3.6 volt about the size of a "fat but short" AA as I recall.
Of course for that matter I don't know if Li-Ion batterys even existed 10 years ago !
(on edit) Looks like the first one's were available in 1999, so sure enough it must have been changed without notice, which means I have no idea when it was actually replaced and this whole post is for nothing except your possible entertainment !
Last edited by Milacron of PM; 04-18-2006 at 09:35 PM.
The biggest problem with Li is that the cells are really intolerant of deep discharge, unlike NiCd's. My notebook battery pack lasted just over a year, and died because I just had to keep working when the battery was announcing that it REALLY wanted to be charged. Since the cells are arranged in series parallel banks, one cell reverse polarizing took out an entire bank. At the time a US$200 lesson, well learned.
I'm a new member to this forum but I had to reply to this post because I used to do research on Li ion polymer batteries. In short, they do degrade, not so much by loss of capacity but rather their internal resistance slowly increases as they are cycled over and over. (Insulating crud deposits on the current collectors, most noticeably on the aluminum cathode.) If the load is a low resistance one such as a motor, eventually the stored energy starts to heat the battery at the expense of running the motor. In other words, some of the voltage is consumed inside the battery and the voltage available to the motor is accordingly reduced. If the load is a high resistance one such as lights, high resistance heaters, computer circuits, etc. this problem is negligible.
The above notwithstanding, these are incredibly efficient batteries and are just beginning to make their way into the commercial world.
Presumably this explains why the camera does NOT have a problem, but the computer does.
Obviously the computer, with a higher draw would be impeded more by a resistance increase.
The curious thing is that the computer battery does not suffer from low capacity, but incredible leakage. The battery only lasts 3 days at most, if unused. If not charged every two days, it barely can be turned on. After three, it will not even start up until charged. I haveyet to try taking it OUT to see if it is an internal problem or a motherboard problem (Toshiba Satellite 1605CD, hardly worth fixing)
The camera, however, has been working since turkey day on one charge. I charged it recently simply because I didn't believe it would run much longer.
In deep discharge applications, the lithium ion packs may be gone after a few hundred cycles. In shallow discharge, they may last for 10,000 cycles or more.
I've been getting good results out of one notebook and three cell phones by faithfully putting them back on the charger whether or not they have significant capacity left. Of course, the charger and the Li-ion's internal controller both play a critical role here also. Just plugging it in doesn't always mean it's getting any more charge.
One thing is constant however. $180 batteries suck
my laptop is 3 or 4 years old now, the Li Ion battery is still good.
What you need to do is remove the protection circuit and draw lots of current from them, then put them in your car while they cool off. Then be totally surprised when your new Honda mini van is burned down to the ground. Oh yes, one R/C pilot learned that lesson. Was not me.
Li Ion batterys are worse than nicads IMHO. I much prefer Nimh (nickel metal hydride) in any application that would require nicads nimh can provide the amps, doesnt have "memory" problem like nicad or simply wear out no matter what like Li Ions. NiMh also weighs about 1/4 the equivalent capacity/amperage nicads. Basically, Lion just isnt worth the bother.
What you are suggesting is that the NEW battery was actually a used battery....... It was that way from day 1.
Originally Posted by nheng
Or possibly there is a constant load of far more than designed in the Toshiba, or theat the Toshiba is a POS to begin with, which may in fact be the case.
I dunno. All I know is that it cost $100 less than your number, but that is still far too much for a bad battery.... Sheesh, ebay purchase reliability from a reputable dealer, in this case, Batteries Plus.