Battery dead? This is for all you naysayers...

[FoxKat]

OK, so I had a real bad day yesterday due to a pulled muscle in my neck, sending shooting pain into my left ear! Nothing like the feeling of a pencil being shoved down your ear canal to to ruin your afternoon. My doctor prescribed muscle relaxers and I obeyed. I took one shortly before bed and don't actually remember putting my head down. Long story short, I never plugged my phone in to charge.

This morning the phone was dead as a door nail, not responding to the power button, so I plugged in the charger and in about 15 seconds the animated battery appeared, but instead of it saying 0%, it started at 5%. This confirms (at least to me) what I've been saying all along.

Have you ever had batteries in something like in a flashlight and watched them die, for instance? Have you then powered off and on again only to have it come on bright for a brief moment and then go dim quickly? How about sitting it down for a while and coming back to find it's bright again, and for longer than before, but eventually dies again? This is the battery slowly finding increased voltage while at rest, because while being used the current being pulled was so strong it pulled the voltage of the battery down. Once relieved of the loud sucking sound the battery starts regenerating voltages. This is a common phenomenon.

The point...if I had actually drained the battery to 0%, and had done so with a battery meter that wasn't calibrated properly (by charging with power off to 100% and avoiding letting it drop much below 15% before charging again), I might have had a BSOD, boot looping or any of a number of other low-battery related issues. Instead once the phone powered down at 0% (as was read by the phone's battery meter), the battery actually started rejuvinating slightly so that once I plugged it in, the voltages were higher and as a result the meter sees the battery at 5%, not 0% or worse.

Anyone care to debate? :icon_ lala:

 

[Mike.757]

I am pretty good about leaving a new phone alone and letting it charge to capacity on the first charge. But I am guilty of just throwing the phone on a charger at night without powering it down (use it as an alarm). Can I benefit from full charging with the phone off or has that ship sailed?

P.S. Hope your feeling better today!:biggrin:

 

[FoxKat]

I am pretty good about leaving a new phone alone and letting it charge to capacity on the first charge. But I am guilty of just throwing the phone on a charger at night without powering it down (use it as an alarm). Can I benefit from full charging with the phone off or has that ship sailed?

P.S. Hope your feeling better today!:biggrin:

Glad you asked Mike!

You would definitely benefit from doing a full charge with power off, I'm saying about once every 2-3 months, BatteryUniversity.com says once every 3-4 months or every 40 full charging cycles. A full charging cycle is the sum of all charges that add up to 100%, so if you charge to 100% and then use to 50% and charge to 100% again, that's 1/2 of a full charge. If you charge to 85%, then use to 15% (*70% consumed), then charge to 85% and use to 55% (30% consumed) and charge to 85%, that's one full charge cycle (70% + 30%).

Also, try not to let the battery dip too far below 15% (low battery warning), before charging again. Finally, it's acutally better for the battery to NOT charge over long charge cycles, but instead to charge more frequently in shorter bursts (like above examples).

For you, Mike, I would charge to 100% (with power off), then use to 15%, and then charge to 100% again (with power off). You'll be good to go from there for the next 3 months or so, then repeat. :biggrin:


P.S. So disrespectful of me, I forgot...THANK YOU for the well wishes!

 

[bruben7886]

FoxKat... I can't think of anyone who has read any of your posts wanting to debate or argue anything with you
Sure hope you are feelin' better today. Oh, remember: muscle relaxers and heavy machinery are not a good pair.....leave the bulldozer in the garage today

Sent from my DROID RAZR using DroidForums

 

[ultra09hd]

And what's the reason behind this?

 

[FoxKat]

FoxKat... I can't think of anyone who has read any of your posts wanting to debate or argue anything with you
Sure hope you are feelin' better today. Oh, remember: muscle relaxers and heavy machinery are not a good pair.....leave the bulldozer in the garage today

Sent from my DROID RAZR using DroidForums

Hmmm...that could be taken 2 ways!! LOL! Thanks for the complement (I think!!) Also, I won't be powering up the JD anytime soon! Thanks again! :biggrin:

 

[justin82]

another great battery thread from the Great FoxKat:biggrin: boy if we only had a sub-forum for it .. check out the signature

 

[SallyC]

Anyone care to debate? :icon_ lala:

Ha! That I'd like to see. View attachment 48500

Can I sell tickets! View attachment 48501

Maybe it goes without saying, but I join all of us in hoping that you're doing better.

 

[bruben7886]

http://www.droidforums.net/forum/showthread.php?t=202046

Yup......this is what happens when you debate with the boss


Sent from my DROID RAZR using DroidForums

 

[FoxKat]

And what's the reason behind this?

If you mean why did the battery show 5% at inception of charge when it had 0% at the time the phone shut down? If so, it's because when voltage and current are being drawn, or better said when there is a load across the battery, it pulls down the voltage versus an open circuit voltage. So when the phone was on and counting down the time to 0%, it was using power (a load), and as a result it was basing the charge values on voltages that were essentially artificially low at that amount of current - but not technically low at open circuit voltage level.

Once the phone shut down when the battery reached 0% of capacity and the load was lifted, the battery voltages rose slightly, enough that when I plugged in the meter read the voltage and said..."OK, this battery is actually at "X" volts, so it is at 5% of capacity, which was "Y" based on the last full charge flag of 100% while powered off and battery low flag at 15% ."

So to summarize, the reason the phone has a low battery threshold is to leave a cushion for emergencies such as being on the phone or in the middle of using the device for internet, and to give you time to get to a charging source. The reason the phone shuts down at 0% is to leave sufficient voltage to allow the phone to activate the charging circuitry when you plug in the charger. If you don't train the battery meter to what the actual upper and lower voltages are (by the charge/discharge methods mentioned), then it can't properly protect you from yourself.

 

[FoxKat]

Here's an analogy that might help to explain the information above to anyone who is perhaps slightly confused...

Imagine you are walking along and not encumbered by anything but your own weight. You can walk at maybe 4.2 miles per hour (open circuit voltage) if you're good. You could probably walk at that pace for a short while, but eventually (self-discharge) you'll start to slow down naturally to maybe 4 mph (initial 20% from 100% so now 80% of capacity) as your energy (capacity) is used up. You may be able to keep up the slower 4 mph for a good long while (80% - 20% capacity), but you'll slow down gradually over time to maybe 3.9, then 3.8, then 3.7 mph . If you continued to walk, your energy (capacity) may start dropping off quickly, 3.6 mph, 3.4, 3.3, 3.2, 3.1 (final 20%), and eventually you'd have to stop 3.0V (0% capacity) otherwise you'd fall down and expire (deep discharge).

But then while you are walking someone asks you if you can carry (current) 20 pounds of potatoes (load). You reply, sure I can, but I will have to walk slower to be able to carry that 20 pounds (voltage pull-down due to current load). So you walk but start out slower (depressed voltage), and you slow down faster over time (decreasing capacity), until finally you say "I can't carry this load anymore", and you stop (0%). But someone like your drill seargent tells you to get up and walk some more, so slightly refreshed (5% recovery of voltage), you start off again but with the potatoes (load), you slow down much faster and stop again.

If you are pushed to the limit and over too many times, you'll never stand up again (BSOD), or you'll stumble and fall every time you try (power cycling, boot loop, etc.)

Maybe this can help people who are having difficulty comprehending the concept of voltage versus current. :biggrin:

 

[Dave12308]

another great battery thread from the Great FoxKat:biggrin: boy if we only had a sub-forum for it .. check out the signature

Only problem is, in the year 2012 we shouldn't NEED a whole plethora of battery threads. Battery technology hasn't changed much in the past several years. Unless you REALLY try to take bad care of a modern battery, they are not that easy to kill due to the safeguards built into both the battery and the charging circuit.

 

[FoxKat]

Only problem is, in the year 2012 we shouldn't NEED a whole plethora of battery threads. Battery technology hasn't changed much in the past several years. Unless you REALLY try to take bad care of a modern battery, they are not that easy to kill due to the safeguards built into both the battery and the charging circuit.

Well, I hear you Dave, and I agree to a point, however people can cause problems even under "normal" use if they normally push the limits too far and too often. The safeguards are there - yes, but unfortunately the battery and the charging circuit and meter can get "out of sync" with repeated partial charges and partial discharges since it loses track of where in the range of the capacity of the battery it is (100% to 0%), because a battery is a finite container, but it gets smaller over time, and will decrease in size (capacity) normally, and faster if pushed to the limits.

Just look at all the threads about "bad battery" and you'll see the effects of improper charging/discharging cycles. You are right...it's difficult to "kill" a battery but it's not too difficult to push its open circuit voltage too low for a proper startup of the phone or charging circuitry.

 

[huskur]

Glad you asked Mike!

You would definitely benefit from doing a full charge with power off, I'm saying about once every 2-3 months, BatteryUniversity.com says once every 3-4 months or every 40 full charging cycles. A full charging cycle is the sum of all charges that add up to 100%, so if you charge to 100% and then use to 50% and charge to 100% again, that's 1/2 of a full charge. If you charge to 85%, then use to 15% (*70% consumed), then charge to 85% and use to 55% (30% consumed) and charge to 85%, that's one full charge cycle (70% + 30%).

Also, try not to let the battery dip too far below 15% (low battery warning), before charging again. Finally, it's acutally better for the battery to NOT charge over long charge cycles, but instead to charge more frequently in shorter bursts (like above examples).

For you, Mike, I would charge to 100% (with power off), then use to 15%, and then charge to 100% again (with power off). You'll be good to go from there for the next 3 months or so, then repeat. :biggrin:


P.S. So disrespectful of me, I forgot...THANK YOU for the well wishes!

This process has been the norm with Apple products..........

Good information that should be followed. Li-ions are not supposed to have a "memory" but flushing them is good time to time. I do it monthly.

I wish one of our members "skull one" would give us his analogy on it. He is likely the most knowledged here on this forum when it comes to batteries and power usage.

 

[justin82]

Only problem is, in the year 2012 we shouldn't NEED a whole plethora of battery threads. Battery technology hasn't changed much in the past several years. Unless you REALLY try to take bad care of a modern battery, they are not that easy to kill due to the safeguards built into both the battery and the charging circuit.

I agree with you. but we all could gain a little knowledge from this . and search the forums see how many threads pop up for battery .. it does not look like it will happen anyway. no one votes thread been open for 36 hours or so and 7 poeple have voted . not much of a response. just trying to help community .