Battery Calibration?

[craigr577]

Breaking In New Batteries -- new batteries come in a discharged condition and must be fully charged before use. It is recommended that you fully charge and discharge your new battery two to four times to allow it to reach its maximum rated capacity. .....

Is this advice, from Laptop-Batteries.org, accurate for MBP? (they give more details, quoted in post #8)
I'm still wondering about first-time use of the battery, especially things to do that could improve its long-term health.

 

[sfroom]

^ no sorry, i completely disagree with everything you just said. modern lithium notebook batteries actually trickle charge while plugged in and fully charged. this means that the battery is discharged down to ~95% and then back up 100% continually to keep the electrons flowing in the battery. it is fine to keep the battery plugged in if you calibrate every 1-2 months. Apple states that the ideal user will use the notebook while commuting and then charge at work.

DO NOT remove you battery while your notebook is plugged in as the CPU only uses one core and one slip of the Mag Safe and your work is gone.

Please read my post, and the Apple battery care instructions, more carefully. You're not disagreeing with everything I said, you're just asserting different information.

I never suggested that the battery would be damaged by overcharging. You're absolutely right, lithium-polymer batteries are not damaged by overcharging the way that NiMh batteries used to be.

However, there are two conditions of leaving your computer plugged into the A/C with the battery installed for long periods of time which CAN and WILL damage your battery.

It has nothing to do with trickle charging.

However, the absolute and undeniable number one way to damage a li-polymer battery is to expose it to heat, whether low intensity over a long period of time, or high intensity for a short period of time. It's quite possible to prove this point by leaving your cell phone in a hot car for a week. Your battery life will be decimated.

The second condition which leads to a deterioration of battery life is STORING the battery at full charge.

Leaving your laptop plugged in for several months exposes your battery to both of these conditions, long term exposure to heat, and storage at full charge.

You are right to note that removing the battery does expose you to some risk, notably that if the cord gets unplugged, your computer will turn off. However, I've found no corroborating source that indicates the computer only uses one core when the battery is not present. A source would be appreciated, as that would be a fairly compelling argument.

For the time being though, I think my advice stands:

1. Do not expose the battery to prolonged or extreme heat.
2. Do not store the battery at either 100% or 0% charge (40% is recommended).
3. Calibrate the battery every two months (this has no real effect on battery life, however, it can improve your perceived battery life. A poorly calibrated battery will sleep your computer way too early, because it thinks it's low on power).

If you want to get REALLY obsessive about it, any time you wont be using the battery for an extended period of time, disconnect it while it is between 40%-60% charge, ziploc bag it (to keep moisture out), and put it in the fridge (NOT the freezer). But I can't say I'd recommend a course of action as extreme as this.

I'm still wondering about first-time use of the battery, especially things to do that could improve its long-term health.

There's nothing you can do the first time you use it to permanently improve long term health, however, cycling it through a few calibration cycles will give you access to your full battery capacity.

 

[craigr577]

Thanks to all of you for the helpful information!
****Earlier, I asked "Are there any reliable guides with accurate information describing factors that affect battery life (specifically in MBPro) and strategies for improving it? ... Is there anything more thorough and accurate?"
****I have questions about "How to prolong lithium-based batteries" by Battery University, http://www.batteryuniversity.com/parttwo-34.htm

****The first question is basic: BatteryU is writing about lithium-ion, but MBPro has lithium-polymer. Are principles of battery life similar for both?

The questions below are about my plan for running the computer at home (before I sleep) about 45 minutes/day, by charging it with AC and then running it on battery until the charge gets low, and running thru the AC/battery cycle again,... My question is about the range of charging and discharging:
BatteryU says "A lithium-ion battery provides 300-500 discharge/charge cycles. The battery prefers a partial rather than a full discharge. Frequent full discharges should be avoided when possible." Is this accurate? If yes, what is the best partial discharge? down to 20%? or to 10, 5, or 2? (the 20% would produce more cycles but it would be more "partial", with the reverse for 2% -- so what is a good minimum end of the cycle-range?)
I'm not sure what they think about fully charging. Agreeing with what's in this thread, BatteryU says to not STORE it at full charge (or high temperature) but should it be temporarily charged to full charge during the charge/discharge cycles? If not, how much less than full charge is ideal?
They recommend "calibrating" occasionally (every 30 cycles) with full charge/discharge. But between these full-range calibrations, what should the "working" range be? Should the top end be a temporary 100%? (or less? 98, 95, 90, 80?) And the low end? (20,...2?)

Of course, another option would be to remove the battery and store it (as described by sfroom) except when I'm traveling, which typically is only a couple of times a year.

 

[Lurchdubious]

Thanks to all of you for the helpful information!
****Earlier, I asked "Are there any reliable guides with accurate information describing factors that affect battery life (specifically in MBPro) and strategies for improving it? ... Is there anything more thorough and accurate?"

Well, are you looking for some scientist to tell you what to do? I mean, as far as reliability, I have had more success relying on personal experience over "theory." I'm up to 581 CYCLES on my 2 yr old blackbook. STILL 100% HEALTH, by doing what I described above. Although, if you're looking for advice from a scientist, I do have a Bachelor of Science degree in Zoology. So I am a scientist.

BatteryU says "A lithium-ion battery provides 300-500 discharge/charge cycles. The battery prefers a partial rather than a full discharge. Frequent full discharges should be avoided when possible." Is this accurate?

Not by my experience, obviously. I charge all the way up, then run it all the way down almost every time.

Of course, another option would be to remove the battery and store it (as described by sfroom) except when I'm traveling, which typically is only a couple of times a year.

Not a good idea. As others have stated earlier, you risked data loss/harming your computer if power is suddenly lost w/no battery backup. Plus you lose performance.