lithium battery life

The latest issue of Shutterbug magazine states that the lifespan of a lithium-ion battery is thirty months, even if you baby them.

I have three lithium BP511-A batteries that I use in three cameras, interchangeably....20D, 30D, and 5D....and I do baby them, but have probably recharged each one at least twenty times.

Should I think about replacing them or not?

Li-Ion batteries aren't affected by the number of charge/recharge cycles as they are from simply aging from the date of manufacture.

You can slow this down by keeping them in the fridge.

Most around here (including me) have had good luck with replacement batteries from Sterlingtek. They're about half the price of the OEM batteries.

After the rated life-time, they'll still charge, but won't hold it very long and won't take as many photos. I've had batteries that I got with my 300D back in 2003 that were usuable in a pinch at this degraded state until about a year ago or so.

That's a crock of ...

I have a stack of li-ion laptop batteries that are ten years old and they still hold a full charge. All five charge leds light up. And I don't baby them.

DK

Well, Don, in these tough times I am hoping you are right. At fifty dollars a pop, I am not anxious to replace my three batteries.....thanks....

Anybody know how a Duracell BP-511A battery compares to the original Canon BP-511A battery? Duracell claims it is better and I can get one for $32 instead of sixty dollars for the Canon OEM.

Charge cycles have only little effect, and li-ion batteries will deteriorate with time even if you don't use them at all. There's also no need for you to discharge the batteries before you charge them again, you can charge the batteries any time (no "memory effect").

They will last the longest if you keep them in the fridge with 40% charge level (not full charge). You should consider this only if you plan on storing them for a long time (weeks/months) without use. And you should NEVER let li-ion cells lose their charge completely, because if the voltage level drops, the cells will be permanently damaged.

You should watch where you buy your batteries, because if the battery has been on the shelf for months, it might be "worn out" even before you use it the first time. After the battery starts to die, it will do so quite fast, within few months.

--
http://mmfoto.posterous.com
http://www.mm-foto.de

The one I got with my old 10D and the spare, purchased almost exactly 5 years ago, started showing their age about 6 months ago. They have been getting constant use with the 10D since purchase (my wife has used it ever since I upgraded to a 20D).

This is consistent with my old laptop, whose Li battery died about 5 years from purchase (and the spare, which was used only once, also proved to be non-functional).

--
Brian Johnson

It does make me smile just a little when I read of price comparisons on camera batteries...

I shoot broadcast video and need 6 batteries at £450 ech and 2 chargers at £500 each. On average I get about 3 years before I have to replace. The units are not re-cellable and I use one of the top manufacturers.

So £60 for a battery seems quite good.

It is true that Li-Ion starts to die the second it is manufactured. Over discharge should actually be quite difficult as the batteries have quite complex electronics to make them safe and an auto cut-off is usually incorporated into the design.

With the new batteries for the 5D2 giving an indication of charge to the camera I wonder if they will need a similar handling as my broadcast batteries. In this respect I occasionally fully discharge the batteries twice and this helps re-set the internal electronics which read the battery capacity. (It makes no difference of course to the actual battery capacity.)

Just an interesting footnote in that the famed "memory effect" of Ni-Cads is something of a myth. N-Cads tend to develop battery imbalance long before any memory effect. One of the best recorded "memory effect" problems was with NASA's early satelites which had strict and repetitive charge and discharge cycles. This gave rise to a true memory effect but only because the discharge cycles wer exactly the same every day. This rarely happens in real world situations and the best way to avoid battery imbalance is to use a charger with intelligent charging techniques such as pulse charging which effectively shock the battery with bursts of charge. (Although I bet our camera battery chargers aren't quite so clever...)

LEE C.

.. in the way that Li-Ion cells will start to deteriorate from the day they are manufactured. and he is right in many other ways.
let me explain my viewpoint:

I heard a good comment directly from a real expert in this field once, he said "it is a corrosive process, there is a definite lifetime for a Li-Ion cell".

he also told what that lifetime was, but I will not repeat this, as it is proprietary information and may vary between manufacturers..

but I disagree with the statement that the number of charge cycles will not affect the lifetime, because it will.

at the start of life, charging and discharging a cell will actually increase its capacity. but then, for each discharge/charge cycle the capacity of the cell will decrease. at some point the capacity becomes so low that one can claim that the cell is wore out. normally, you reach this point after a thousand discharge/charge cycles or more. that would be about three years in daily use.

but a deep discharge will have more effect on lifetime than a shallow discharge. and
high temperature will accelerate decay, as with all chemical processes.

storing the Li Ion battery at a low temperature will certainly slow down the corrosive process, and would be an advantage if the battery is not used every day.

high temperatures, storing the battery so hot that you burn your fingers handling it, will mean the battery dies prematurely. do not leave a Li Ion battery in your car on a hot day.

there is no need to discharge a Li Ion battery before charging it, this would only reduce its lifetime.

sometimes it is necessary to do a so called calibration of a battery, which means to fully discharge and then charge a battery so that the built in electronics - especially the fuel gauge function- can collect data on the actual capacity of the battery.

this information captured during the calibration cycle is used to calibrate the fuel gauge so that it becomes more accurate. the measurement data tells the electronics what the actual capacity of the battery is, at that point in time.

(note that not all battery packs have built in fuel gauge. but my Canon 1D Mark III battery does. and the charger is sophisticated too)

there may be other advantages in the way that during the calibration cycle the cell balancing function is able to restore a battery to balance, that is fully charge each cell so that the full capacity of the total battery pack can be utilized. usually, the cell balancing circuit is able to keep a battery in balance if it is well designed, without requiring a calibration cycle.

Tage

Jari Karppanen said:

Charge cycles have only little effect, and li-ion batteries will
deteriorate with time even if you don't use them at all. There's also
no need for you to discharge the batteries before you charge them
again, you can charge the batteries any time (no "memory effect").

They will last the longest if you keep them in the fridge with 40%
charge level (not full charge). You should consider this only if you
plan on storing them for a long time (weeks/months) without use. And
you should NEVER let li-ion cells lose their charge completely,
because if the voltage level drops, the cells will be permanently
damaged.

You should watch where you buy your batteries, because if the battery
has been on the shelf for months, it might be "worn out" even before
you use it the first time. After the battery starts to die, it will
do so quite fast, within few months.

Click to expand...

--
http://www.thisbeautifulearth.com

I do not disagree with anything said,

my comments:

the best way to quickly destroy a Li-Ion battery is to do a deep discharge that brings the cell voltage below a critical point (depends on the cell, but anything 2V per cell would be a gamble). so do not store a Li-Ion battery that is completely discharged - especially not in the camera, as the discharge may continue below the critical point.

fortunately, many battery packs have built in electronics that will disconnect the cells and stop the discharge when a cell voltage has dropped below a certain level. but this is not always the case. in some cases the electronics is in the camera and not inside the battery.

with other gadgets that use Li-Ion batteries, the battery electronics may be omitted and the battery pack is only a bunch of series connected cells, a recipe for disaster but the reason is to reduce cost and some companies find that it is acceptable to replace some nonfunctional batteries on warranty when consumers complain, instead of designing a battery that will last. in real life, many consumers buy a gadget and it is left in the garage never to be used again.

the slow way to destroy a Li-Ion battery is to store it at a high temperature.

Ni-Cd batteries are hardly used any more due to the toxic materials, so this has only historical interest, but I agree on the viewpoints mentioned.


Tage

leethecam said:

It does make me smile just a little when I read of price comparisons
on camera batteries...

I shoot broadcast video and need 6 batteries at £450 ech and 2
chargers at £500 each. On average I get about 3 years before I have
to replace. The units are not re-cellable and I use one of the top
manufacturers.

So £60 for a battery seems quite good.

It is true that Li-Ion starts to die the second it is manufactured.
Over discharge should actually be quite difficult as the batteries
have quite complex electronics to make them safe and an auto cut-off
is usually incorporated into the design.

With the new batteries for the 5D2 giving an indication of charge to
the camera I wonder if they will need a similar handling as my
broadcast batteries. In this respect I occasionally fully discharge
the batteries twice and this helps re-set the internal electronics
which read the battery capacity. (It makes no difference of course
to the actual battery capacity.)

Just an interesting footnote in that the famed "memory effect" of
Ni-Cads is something of a myth. N-Cads tend to develop battery
imbalance long before any memory effect. One of the best recorded
"memory effect" problems was with NASA's early satelites which had
strict and repetitive charge and discharge cycles. This gave rise to
a true memory effect but only because the discharge cycles wer
exactly the same every day. This rarely happens in real world
situations and the best way to avoid battery imbalance is to use a
charger with intelligent charging techniques such as pulse charging
which effectively shock the battery with bursts of charge. (Although
I bet our camera battery chargers aren't quite so clever...)

LEE C.

Click to expand...

--
http://www.thisbeautifulearth.com

but you should carry a spare battery if the one you are using is more than three years old.

Tage

Dave1234 said:

The latest issue of Shutterbug magazine states that the lifespan of a
lithium-ion battery is thirty months, even if you baby them.

I have three lithium BP511-A batteries that I use in three cameras,
interchangeably....20D, 30D, and 5D....and I do baby them, but have
probably recharged each one at least twenty times.

Should I think about replacing them or not?

Click to expand...

--
http://www.thisbeautifulearth.com

Get yourself a spare battery and take it with you, particularly if it will do for all the cameras. When one runs out, put the pare in and the empty goes to the charger once home.

I've used 2 BP-511a and 3 generics in this way, and you just never get into battery problems that way. One of the generics did eventually die a sudden death (would no longer recharge, so didn't cause a problem in the field), but all others are still performing fine, I haven't noticed any reduction of charge after 3-4 years.

I have a 511 from my 20d which I've never replaced. I've also only charged it maybe 20 times in the 4 years or so since the 20d's release. The camera was never low enough on charge that entire time to stop working either.

On the other hand, in the two years I had my previous macbook pro I was forced to replace the battery twice.

The major killer of batteries is usually regarded as being heat. Whether its high heat due to a very high discharge rate or high heat due to a very high charge rate.

Discharge rate-wise it would have been hard to make my old 20d discharge the battery very fast because it had no live view and no mode where the sensor was continuously on. And of course only charging it 20 times means that I barely ever generated any charging heat.

The other thing that sometimes kills lithiums is deep discharge. This is hard to actually achieve via pure self-discharge though. Plus I think the camera refuses to use the battery at all below a certain point so that it can't directly draw down the battery to deep discharge.

I suspect (sadly) that these days are now over though. My 5d mk2 gets HOT when I run a lot of video or use the live view a lot. Pulling the battery at that point reveals that it is QUITE warm. I could probably reduce the wear by getting a power adapter cord for when I shoot product photography, but I think I'll just live with having to replace the battery eventually.

My 9 Year old Canon D30 and li-on battery is still ticking, it doesn't hold a full charge any more, good enough though.

Most interesting, here is what Canon says about the latest 1D batteries...

http://www.usa.canon.com/dlc/controller?act=GetArticleAct&articleID=886&fromTips=1