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View Full Version : OT...Lithium-ion battery inherent defect?



J Tiers
04-18-2006, 06:32 PM
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?

Evan
04-18-2006, 06:38 PM
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.

Milacron of PM
04-18-2006, 10:29 PM
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 ! ;)

bob_s
04-18-2006, 10:45 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.

stearman26
04-18-2006, 11:08 PM
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.

J Tiers
04-19-2006, 12:25 AM
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.

nheng
04-19-2006, 12:44 AM
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 ;)

Den

BillH
04-19-2006, 12:46 AM
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.

Mortimerex
04-19-2006, 04:43 AM
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.

J Tiers
04-19-2006, 10:21 AM
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.

Den

What you are suggesting is that the NEW battery was actually a used battery....... It was that way from day 1.

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.

HTRN
04-19-2006, 11:04 AM
The Li Ion battery "shelf life" issue is half the issue of the Ipod uproar.

The other was the difficulty of consumers changing the battery(it involved product disassembly), and Apples attitude of "Screw you, buy another one".

There is another issue with the Li-Ion battery life - it has a life of a couple of years WHETHER IT'S USED OR NOT.

In other words, a battery that sat on the shelf for 4 years is going to be dead as a doornail despite never being used. This has something to do with Battery Chemistry.


HTRN

Evan
04-19-2006, 11:46 AM
That is what is meant by poor "calendar life". They deteriorate whether they are used or not.

J Tiers
04-19-2006, 02:11 PM
Sehr schlect!

I am thinking that the Li-Ion batteries just plain suck, and ought to be pulled off the market until they can get it right.

What the heck were they thinking?

Fasttrack
04-19-2006, 06:19 PM
Don't quote me on this, but i believe the electrolyte they use (an organic based electrolyte although i've heard rumors about research done with new electrolytes that are much less reactive and electrodes made out of lithiated metal oxides) is slightly reactive with aluminum - higher draws and over a long period of time, in my mind anyway, would cause the slightly reactive organic compound to decompose and form non-conductive compounds at the cathode.

darryl
04-19-2006, 10:28 PM
It's a conspiracy!
Well, whatever. Back in the early seventies, I bought a set of alkaline rechargeables. These worked faithfully for over three years, getting used almost every day, so realistically that was probably about 800-1000 full charge/discharge cycles. The 'high drain' device was my mono casette player, which went to every party, and was the 'system' in the vehicle I drove. It was most often cranked to just below the point of distortion, so it was working to capacity for most of it's life. (just like the four-banger in the van :)). Sometimes I would leave the cells on charge too long and they would get quite warm, other times I would top them up until I could feel them heat somewhat. They didn't leak or explode, but they did start to weaken and poop out early after the three years or so. No matter, that co-incided with my purchase of a 'real' car stereo, so at that point the rechargeables went in the trash, and the mono casette player went on the shelf for a few years until I could bring myself to toss it.
In any event, it would seem that the alkaline rechargeable technology has gone downhill since then- why should that be? Same reason all this 'new' battery technology isn't a good, stable, reliable thing- this is no different than the pharmacies not wanting to stop selling cigarettes even though it's a proven health hazard. It's all about the money- keep the public paying, and paying, and paying-

paulgrandy
04-20-2006, 10:17 AM
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It's a conspiracy!
Well, whatever. Back in the early seventies, I bought a set of alkaline rechargeables. These worked faithfully for over three years, getting used almost every day, so realistically that was probably about 800-1000 full charge/discharge cycles. The 'high drain' device was my mono casette player, which went to every party, and was the 'system' in the vehicle I drove. It was most often cranked to just below the point of distortion, so it was working to capacity for most of it's life. (just like the four-banger in the van :)). Sometimes I would leave the cells on charge too long and they would get quite warm, other times I would top them up until I could feel them heat somewhat. They didn't leak or explode, but they did start to weaken and poop out early after the three years or so. No matter, that co-incided with my purchase of a 'real' car stereo, so at that point the rechargeables went in the trash, and the mono casette player went on the shelf for a few years until I could bring myself to toss it.
In any event, it would seem that the alkaline rechargeable technology has gone downhill since then- why should that be? Same reason all this 'new' battery technology isn't a good, stable, reliable thing- this is no different than the pharmacies not wanting to stop selling cigarettes even though it's a proven health hazard. It's all about the money- keep the public paying, and paying, and paying-

The entire Rechargeable Tool business is a conspiracy. It's about selling batteries.

When the batteries crap out this is what you can do. Go to Radio Shack and get a male and female plug. Use the old battery and route a line from the battery pole thru the battery to the female jack(drill a hole in the battery case for it). Wire the male plug to a Car Battery Charger.

I did this with a 9.6 Craftsman and ran it at the 10amp setting. Works fine. Little low on torque though. Someday I may buy a better charger. Vector makes a 2/10/20/40 Amp Smart Battery Charger. 20 amps would probably be OK for my 9.6.

Battery's seem to cost more than the cost of a new tool with a couple of batteries. Last cordless I bought was a Ridgid with a Lifetime Warranty on everything, including the batteries. We'll see if they honor it when the battery craps out.

J Tiers
04-20-2006, 10:21 AM
It's more about the rush to china.... lowest price means you cannot afford decent quality, so you don't get it.

Then, yes, its cheaper to buy more stuff than to fix it...

But, in this particular case, it is not the NiCd, but the Li-Ion type. A new tech part, sort-of, which it seems has a defect which cannot be fixed.

The article was concerning electric cars, which are far more practical than hydrogen, and would benefit from Li-Ion, if they worked, which those batteries do not.