charge battery to 80% only

Does you notebook have the option to charge to 80% , basically a battery saver , but how much longer will the battery live for.

I asked this question on a forum , that specialist in li-ion battery`s , and got a interesting answer.

If you only charge to 80% , you "might" get up to 2000 cycles

But at 100% charge you only get around 500 cycles.

I think you should look at 750-1000 cycles if you charge to 80% , which is worth the 20% loss in runtime for my needs.

I am not certain how accurate these number are but they are interesting.

A link to the forum were i asked the question is below.

http://www.candlepowerforums.com/vb/showthread.php?t=241995

 

it make sence because your charge cycle is less when you charge to 80% than if you charged to 100%.

What I'm saying is that if your have shorter charge cycles, you will more of them before the battery dies.

But you are actually getting about the same value out of the battery.

 

I don't believe that's right. Lenovo and Sony offer the option of charging to 80% because it does help prolonging battery life.

 

Well, after a bitover 1 year I now have 4,5% wear on my Vaios battry, andexcept less than 10 times it always charges to 80% only.

Now, I think most of that wear was heat - or occured in the summer, in Winter 08 (after about 6 months) I was at 1% wear.

I suspecgt the wear is due to me using Intel's latest graphics drivers for the X3100 which aren't really compatible with the SZ.

Why do I say not compatible:
Well, the GPU runs much hotter, and even crashes on the latest drivers.

The much weaker stock drivers let the same laptop run cool.


So: Overall, wear is very small at an 80% charge.

 

How hot the battery gets , by being close to the cpu/gpu can decrease it`s lifetime considerably.

 

I know, I've read it before.

And Intel's newest drivers are pointless in an SZ - they just try to fry the laptop...
I'm not sure why...

 

I've only seen this 80% charge option on a Sony G11 and I wondered if it was because of the very high capacity battery.

A more effective way to reduce the charge cycles is to have a a threshold below which the charge has to drop before the battery recharges. This avoids the small top-up charges. I've seen this implemented on many notebooks. Fujitsu used to use 90%. Samsung uses 97% (IIRC) and I have just discovered that my Dell E6400 has a threshold of 95% for the 9 cell battery but does top-up charges on the 6 cell! However, the charge rate as the battery approaches 100% is very low.

John

 

Well the 80% and 50% charge limit ia available on the Sony Vaio SZ7 too - that's my laptop

 

My Samsung N310 netbook has an 80% charge setting in the BIOS and you can set it in XP also, do the other Samsung netbooks not have this function?

I think an 90% setting would be better, but maybe they thought it would be too difficult to get 90% 4.1volt per cell every time, and so they went with 4.0volts 80%

4.2V = 100%
4.1V = about 90%
4.0V = about 80%
3.9V = about 60%
3.8V = about 40%
3.7V = about 20%
3.6V = empty
<3.5V = over-discharged

 

Several Sonys have it. Samsung N120 has it too, N110 and NC10 don't.

 

what use is a 50% setting?????

I had an eCafe netbook you could not set the battery charge level, but the charge indicator would turn from orange to green at 90% and turn off at 100%

 

The 50% setting is for home use, when the battery is only needed to carry the laptop from one room into another.

 

50% how far are these room apart

 

I actually charge mine to 50% now, if i do need to use my battery which i don't much anymore on this laptop i will charge my battery to 100% and then set it back to 50%.
Charging to 50%-80% is very good for those who mainly keep their notebook plugged in and don't also run their notebook down once a month.

I actually thought i would have had some battery wear by now but apparently i don't. My battery is still at 100% health after 17 months.

 

Ideal charge for storage of a Li-On batteryis 40-60%

 

To the best of my knowledge charging to 80% is also good of you travel around - at least on an SZ.
Never did me any harm for 1 year at university.
(Now on to year 2)

 

mines lost only about 10% of its capacity after 9 months... but doesn't matter i still got a spare battery which i haven't used...

 

you should charge it to 40% and put it in a sealed plastic bag, and put it in the refrigerator to keep the battery as fresh as possible.

just check it every couple of months, but allow it to come up to room temperature for a couple of hours first.

 

I would nver do that... you should nver put batteries or electrical stuff in cold environments.....

 

Actuall that is the best storage for a battery.

Ideally, charge to between 50-60% is what I've read - I think Tinderbox said 40%, put it in a ealed bag and store in a freezer.

Eectronics actually love a cold environment.

Problems arise if condensation occurs in the unit.

 

Dont just believe me.

http://www.candlepowerforums.com/vb/showthread.php?t=241957

 

Wrong! In fact, your battery deteriorates even if it's just stored away. Fact is, every charge counts! So 500 cycles is all you get--regardless of what percentage it begins or ends at.

 

Actually, charging it fully increases wear.

Charging just to 80% is good, also due to less heat.

 

If you look at it that way then you have a point. I take fore granted that there is an understanding that 500 cycles that was mentioned is not an exact number. There are indeed many other factors (i.e. temperature humidity etc.) that effect battery life as as whole. Similar to automobile mileage estimates, your actual mileage may vary.

 

+1(except I go to 80% when I need to use.)

I am always plugged at home, specifically in my room and charging to 50% will really help prolong the battery use.

 

Your the one who`s wrong!

If stored at 25c and 100% charge the battery will loose 20% of it`s capacity/wear in a year.

But if stored at 0c and at 40% charge the battery will only loose 2% capacity/wear in a year.

it`s all in black and white below.

http://www.batteryuniversity.com/parttwo-34.htm

 

I did say apparently, i actually think that RMClock might possibly not be the most reliable tool to measure battery wear but it was indicating that i had 0% battery wear and most people here seem to use RMClock.

My usage might seem like a lot to me but relatively it is probably still not a lot. I have probably used it about 60-70 times on battery. This would have been enough for 30 times during term one last year and may be 30 times at most during term two. It probably was not as much as that. I have actually ran my battery right down to being fully discharged a handful of times.

So whilst my battery might not actually be at 100% and i could believe that, the wear level should be low.

I started out charging my battery to 80% about four-five months ago and then two months ago started charging to 50%.

 

Whether you use RMClock, BatteryBar or ..., it will read the same health.

The reading is as accurate as the technology reading the information.