Calibrate Battery?

[FoxKat]

why not let it drain all the way instead of 15%?

You can "technically" let the battery drain to 0% (where the phone powers down itself), however if the meter isn't properly calibrated to the battery (not the other way around), then there's a possibility that when the phone eventually shuts down the battery may actually be close to a critical level that will fail to respond next time you try to charge it. There have been many "bootlooping", "white light of death", "black screen of death", "power cycling" threads where they all originated from a phone that was allowed to drain and power down on its own.

For the record, I've left my phone drain to 0 and power down a number of times with no negative consequences, but did so just to see if it would fail as others' have. Of course, my meter is properly calibrated to the battery so I felt confident it would respond as it did. I attribute the failures to the meter inaccurately representing more power at the nearly completely discharged level than the battery actually has, so the phone doesn't shut down soon enough to prevent deep discharging. So a healthy battery meter will result in the auto-power down executing at the right voltages and leaving enough power to allow for connecting to a charger later and being able to boot into charge only mode.

Good question, It may have to do with the software figuring out when to issue a "Charge Now" warning. I'm sure FoxKat knows.

Excellent deduction, Watson... The phone indicates "Low battery" at 15% (10% for Jelly Bean), for three very good reasons.

1. That's when the voltages start to drop faster than it does over the previous 70% or so, and that's the indication that the meter is looking for to determine when it's approaching the cutoff voltage for full automated power down.
2. That's a good level to warn you of impending doom (like the Low Fuel light on your car's dashboard), essentially telling you that you are now running on the "reserve tank". This way you have time to save any work you're actively working on, say goodbye to the person you may be on the phone with, finish that last text or email and send it, make the emergency call to warn the wife/husband/BF/GF that the phone is about to die, and get to the nearest source of power to replenish the phone's battery.
3. It sets the flag for "Low battery" at that level, and then with that flag and the one it sets at 100% charged, can now make fairly accurate estimations of how much power is remaining anywhere along the discharge curve. Without those two flags, it would be guessing (inaccurately), and would begin to stray from the actual numbers farther and farther as time and power/charge cycles are completed.

Boyfriend's having the same problem with the Seido 4000mAh battery. He's let it discharge and then charged up with the phone off several times, and it still stays on 1% for like 20 hours before it finally dies.

This is not so much a meter that's not calibrated as it is a battery that's not falling within the ranges that were spec'd for the phone, or in other words, a battery that's simply not 100% compatible. It may power the phone, but as you and others have found out, it will probably provide terrible level indications.

 

[FoxKat]

The heck with calibration. Tried them all, it still doesn't show correctly. Get the battery monitor widget. When my battery reads 3200 mV, I know the end is a few minutes away. Getting around 16-18 hours out of my vzw extended battery, using savings settings. Shut off data and Wi-Fi when not in use. Love the slimmer size(2760) vs the 4000, which is now sitting in my drawer.

This "workaround" is a viable one, and as long as you are monitoring the voltages and don't miss the threshold you've set for yourself (a safe one is the 3,200 mV or 3.2 V you mention), then the battery will still have sufficient power to remain ready to take a charge and resume powering the phone (+3 V). If the voltages drop much below 3 V, then the phone may fall into one of the bootlooping sequences I've mentioned, and recover can be quite a task. If the voltages actually manage to dip to somewhere between 2.5 V & 2.7 V, you may be looking at a battery that has gone into "protection mode" state and will not come out unless essentially "defibrillated" into normal state again. Some batteries can be recovered from Protection Mode, but not with the charger that comes with the phone. Instead it takes a very carefully monitored and executed series of jolts of substantially higher voltage to wake it from that state, and even those jolts may not be successful depending how deep the voltage has dropped. The only option left at that point is replacement.

 

[FoxKat]

By the way, since this thread deals specifically with Smartphone Battery issues, I am moving it to the newly created Smartphone Battery Discussion forum. There will still be a link on the Bionic forum that will take you to the original thread in its new home.

Moving now.

 

[bobbyp]

I am going to post my question here and hope for a response. I am pretty good about calibrating my OEM extended battery. When I travel though I switch back and forth between it and the standard battery that came with my Bionic. Will my battery meter be agitate when I do this? Not sure if its the. 905 update or not but I was locked in 3g using gps and after having a full charge I was down to 50% in about two hours and it stressed me out because my car charger wasn't working. Was it possibly just an error reading the battery?

Sent from my DROID BIONIC using Droid Forums

 

[FoxKat]

I'm going to bet your suspicion is correct. For the meter to accurately indicate what the charge level is at any particular point in time, it uses the moving averages of the maximum charge level flag and the most recent 15% "low battery" flag, 10% with Jelly Bean. The problem becomes which battery was in when these level flags were set? Then once set for one battery, they are going to be inaccurate for the other.

Sent from my DROID RAZR using Tapatalk 2

 

[APQuijano]

Hello! New to the forum and somewhat a smartphone noob and had a question about calibrating.

I just recently got the Razr MAXX and I was one of those guys who didn't charge the phone to 100% while off out of the box (I was just way too excited). Only had the phone for a couple of days and was wondering if it's still possible to properly calibrate the phone using the "charge to 100% while off" method. If so, does the phone need to be in a particular charge state to do this? For example, can I calibrate the phone when it's at 75% or does it need to be lower?

 

[FoxKat]

Great question and the answer is yes and no...

No, I'm not going to leave you hanging. LOL! Yes it can be calibrated to the battery at any time, and no it doesn't need to be at any particular charge level, since the three step charge, discharge, charge runs the phone past the flag points. Also, there is no lasting "damage" to not having done it immediately. The only reason why I stress you do if you can is because MOST people are going to do just what you did, use it till you drop as soon as you get it. There is a risk of pushing the battery voltages so low that the phone won't respond to the charger (White Light of Death), or may begin looping during boot (bootlooping), or cycling through power ons and offs (powercycling). This could happen if you use the phone till the level reaches 0% and the phone shuts down on its own. Unfortunately if this happens it can be difficult, and even not possible to recover from.

So go forth and conquer. Do the meter training and you'll be fine. :biggrin: You'll want to charge to 100% with power off, then use to 15%, and then power off and charge to 100% with power off again. After that, if you perform that practice about every 3 months or so, you'll be good to go.

 

[APQuijano]

Great question and the answer is yes and no...

No, I'm not going to leave you hanging. LOL! Yes it can be calibrated to the battery at any time, and no it doesn't need to be at any particular charge level, since the three step charge, discharge, charge runs the phone past the flag points. Also, there is no lasting "damage" to not having done it immediately. The only reason why I stress you do if you can is because MOST people are going to do just what you did, use it till you drop as soon as you get it. There is a risk of pushing the battery voltages so low that the phone won't respond to the charger (White Light of Death), or may begin looping during boot (bootlooping), or cycling through power ons and offs (powercycling). This could happen if you use the phone till the level reaches 0% and the phone shuts down on its own. Unfortunately if this happens it can be difficult, and even not possible to recover from.

So go forth and conquer. Do the meter training and you'll be fine. :biggrin: You'll want to charge to 100% with power off, then use to 15%, and then power off and charge to 100% with power off again. After that, if you perform that practice about every 3 months or so, you'll be good to go.

Thank you very much your quick response and time! I definitely will make sure to make this is common knowledge to friends and family now.

 

[Trash Can]

You can "technically" let the battery drain to 0% (where the phone powers down itself), however if the meter isn't properly calibrated to the battery (not the other way around), then there's a possibility that when the phone eventually shuts down the battery may actually be close to a critical level that will fail to respond next time you try to charge it. There have been many "bootlooping", "white light of death", "black screen of death", "power cycling" threads where they all originated from a phone that was allowed to drain and power down on its own.

There is a risk of pushing the battery voltages so low that the phone won't respond to the charger (White Light of Death), or may begin looping during boot (bootlooping), or cycling through power ons and offs (powercycling). This could happen if you use the phone till the level reaches 0% and the phone shuts down on its own. Unfortunately if this happens it can be difficult, and even not possible to recover from.

Hey Professor, a good student always challenges his teacher.

To an outside observer like myself, a lithium polymer battery is a lithium polymer battery. So why would charging recommendations vary from one manufacturer to another? Specifically, any idea why Apple recommends a full charge/discharge cycle once per month? The last paragraph on this Apple battery page says:

Use iPhone Regularly
For proper maintenance of a lithium-based battery, it’s important to keep the electrons in it moving occasionally. Be sure to go through at least one charge cycle per month (charging the battery to 100% and then completely running it down).

I realize we're making an Apple to Razr/Bionic/Rezound comparison (pun intended), but conflicting information can be confusing information. :icon_eek: Any insight that you can provide would be greatly appreciated, as many members here are former or current iPhone/iPad owners.

 

[DamianD]

If during calibration (charging with power off in the cycle 15% to 100%) happend a general power outage for 5-10 minutes, after the power failure charging restarts, this has some effect for calibration/battery?

 

[FoxKat]

Hey Professor, a good student always challenges his teacher.

To an outside observer like myself, a lithium polymer battery is a lithium polymer battery. So why would charging recommendations vary from one manufacturer to another? Specifically, any idea why Apple recommends a full charge/discharge cycle once per month? The last paragraph on this Apple battery page says:



I realize we're making an Apple to Razr/Bionic/Rezound comparison (pun intended), but conflicting information can be confusing information. :icon_eek: Any insight that you can provide would be greatly appreciated, as many members here are former or current iPhone/iPad owners.

Sorry I'm just seeing this now, but let's run with it.

You're thought process is not flawed, there are variables that determine what constitutes a full discharge. For one device manufacturer, a 0% of capacity may be at 3.2V, whereas another may peg it at 3.0. Obviously 3V is much closer to the "protection" Voltage of between 2.2V & 2.9V, so if one manufacturer says run it down, and another one says don't, the difference could be the cutoff voltage.

Second, all Lithium batteries are not created equal. Lithium Ion Polymer Pouch Packs (in the RAZRs), are a different breed than all other LIPO batteries and are both higher in energy density and also come with their own unique characteristics.

Another important issue is that with the LIPO Pouch Cells, the phone itself contains the protection circuits and charging circuits, so each phone manufacturer can tweak the various levels for things such as running voltages, cutoffs for charging and discharging, and the protection level. Apple may actually have their discharge level cutoff at a higher voltage than Motorola, and as a result there is a bigger cushion between 0% and the potential cutoff protection voltages.

Also I checked the page you linked to and saw the quote you referred to, but I did also find this http://www.apple.com/batteries/, and it says in one section:

"You can also recharge a lithium-ion polymer battery whenever convenient, without the full charge or discharge cycle necessary to keep nickel-based batteries at peak performance. (Over time, crystals build up in nickel-based batteries and prevent you from charging them completely, necessitating an inconvenient full discharge.)"
​

This is in direct contrast to the quote you showed. Perhaps the issue here is what they call "completely running it down". In the RAZR, completely running it down is to 15% (10% with Jelly Bean), NOT to 0%. When the phone tells you it's time to plug in (the "Low battery warning at 15% - 10% with Jelly Bean), then you can reasonably conclude it's time to plug in.

The same holds true for the iPhones. What people do is misinterpret that information to mean 0%. If Apple OR Motorola wanted you to discharge to 0%, they'd say it this way; "use your phone until it shows 0% on the display". If they wanted you to use it until it powered itself off with a completely deep-discharged battery, they'd say; "run your phone until the phone shuts off on its own". that's NOT what it says.

If your car manufacturer told you to run the car till it was empty once a month, how many people do you think would actually do it? NONE? You'd have to drive on "E" for many miles, and then you would also have to carry with you a gas can full of gas so you could start the car again and drive it to the nearest station after it stalled at completely empty. I really don't think that either Apple OR Motorola meant "completely discharged" when they say "completely run it down".

In fact, the same thing Apple is saying is what I've been saying too...charge to 100%, use to 15%, charge to 100%, or in layman's terms, "Charge to 100%, then completely run it down, then charge to 100% and use normally". This is a meter calibration cycle. Nothing new here folks, move along.

Sent from my DROID RAZR using Tapatalk 2

 

[FoxKat]

If during calibration (charging with power off in the cycle 15% to 100%) happend a general power outage for 5-10 minutes, after the power failure charging restarts, this has some effect for calibration/battery?

No, none whatsoever. It would simply pick up where left off and continue.

 

[DamianD]

Ok, ...I just thought that it may occur an error in the calibration and a correct and safe way would be to resume the whole process again (discharge to 15%, power off and charge to100%)

 

[FoxKat]

Here's some more interesting information from Apple, which also corroborates my claims;

Standard Charging

Most lithium-ion polymer batteries use a fast charge to charge your device to 80% battery capacity, then switch to trickle charging. That’s about two hours of charge time to power an iPod to 80% capacity, then another two hours to fully charge it, if you are not using the iPod while charging. You can charge all lithium-ion batteries a large but finite number of times, as defined by charge cycle.

Charge Cycle. Using and recharging 100% of battery capacity equals one full charge cycle.

A charge cycle means using all of the battery’s power, but that doesn’t necessarily mean a single charge. For instance, you could listen to your iPod for a few hours one day, using half its power, and then recharge it fully. If you did the same thing the next day, it would count as one charge cycle, not two, so you may take several days to complete a cycle. Each time you complete a charge cycle, it diminishes battery capacity slightly, but you can put notebook, iPod, and iPhone batteries through many charge cycles before they will only hold 80% of original battery capacity. As with other rechargeable batteries, you may eventually need to replace your battery.

​

They're also showing the collective charges of the first 40%, then 20%, then 30%, and finally half of the next 20% constitutes the first 100% cycle (1 cycle), and the second half of the last 20%, along with the 50%, and 40% of the next 60% constitutes the second 100% cycle (2 cycles). So in that graphic, he's already 20% into his third 100% cycle.

Sound familiar? Remember what I said all along, complete 100% cycles (or a collective of multiple partial cycles)?

What they're showing is the following:

Charge to - Use to

100% ----- 60% (first 40% consumption),
100% ----- 80% (next 20% consumed),
100% ----- 70% (next 30% consumed),
100% ----- 80% (next 20% consumed),
100% ----- 50% (next 50% consumed),
100% ----- 40% (last 60% consumed).

The same could be accomplished like this:

Charge to - Use to

80% ------ 40% (first 40% consumption),
60% ------ 40% (next 20% consumed),
70% ------ 40% (next 30% consumed),
60% ------ 40% (next 20% consumed),
90% ------ 40% (next 50% consumed),
100% ----- 40% (last 60% consumed).

or;

Charge to - Use to

60% ------ 20% (first 40% consumption),
40% ------ 20% (next 20% consumed),
50% ------ 20% (next 30% consumed),
40% ------ 20% (next 20% consumed),
70% ------ 20% (next 50% consumed),
80% ------ 20% (last 60% consumed).


In those three examples, the first one would yield the shortest overall battery life because each charge was to 100%. The second would yield longer battery life because only 1 of the charge cycles took the battery to 100%. The third would yield the longest battery life, because the battery remained in the range of 20% to 80%, or the widest sweet spot.

 

[FoxKat]

Ok, ...I just thought that it may occur an error in the calibration and a correct and safe way would be to resume the whole process again (discharge to 15%, power off and charge to100%)

Great thought process. The reason it doesn't throw off the calibration cycle is because the calibration flags are only set when the battery reaches the 100% charge (sets the "Full" flag), and when it reaches the 15% discharge (sets the "Empty" flag).

Still, a great question. :biggrin: