Updated Battery Life and Usage

[jimmythegent]

Great question and observation. I've tackled this very issue of differences between power tools and phones in the past, but the short of it is they both draw current at very different rates (when's the last time you drilled with your power tool for 25 straight hours, non-stop?), and the two battery types are actually significantly different in chemistry. One is designed to provide high current in short bursts of relatively similar current levels (drill), the other is designed for low current draw over extended periods of time and at comparatively widely varying current levels (phone).

Simply by the way power is consumed in the drill, it's very easy for the tool to know when the battery needs to be charged... As it nears being depleted, the high current draws start depressing the voltage, the drill begins to slow and lose torque, and the voltage drops precipitously. Those significant changes in voltage are very easy to detect and the result is the monitoring circuit says "were near the end, shut down now to protect the battery."

In contrast, a phone's current draws are mostly very low and the battery can easily keep up with the demand for current without suffering voltage drop, even when near the critical low voltages where the power tool would have long since given up completely. Since the voltage doesn't drop in a pattern that is easily discernible, the metering circuitry has a much harder time determining when to call it quits.

Furthermore, you don't likely have a power meter on your power tool that tells you in 10% (or for that matter 1%), increments how long you have until charge is needed. If your power tool dies in the middle of a job, you pull another off the charger, slap it on and continue where you left off. However if your phone battery dies, it could be life threatening or financially devastating, such as not being able to make a call to 911, our losing your connection to the client you were trying to persuade to do business with you. In other words, the phone is far more mission critical, so the battery must be able to stand tough for those marathon sessions and still deliver.

So the phone's meter needs to not only accurately know what the full charge and depleted charge looks like, but also calculate where along the path to depletion it is at any given time, through a very long and gradual voltage depletion phase, and make sure it doesn't get too deeply depleted least it trigger the battery's protection mode...a very tough job. Add to that, the fact that one high current draw due to perhaps streaming a movie in a poor cellular coverage area could depress the voltage low enough even when sufficient current remains, to essentially "fool" the meter into thinking the battery is dead and trigger a shut-down.

Over time as it "sees" these voltage dips and interprets them as a depleted battery, it then uses those artificially depleted voltages as the "new low". There have been many cases where the phone says the battery is depleted but the phone remains running for hours past when it should have shut off if the meter were accurately gauging the remaining power. The inverse is when phones report there's 40% remaining, then only minutes later shut down without warning and become unresponsive to the charger.

There's lots more to it than this but to hopefully keep from boring nearly everyone to sleep I'm trying to condense it.

Sent from my DROID RAZR using Tapatalk 2

Wow. Can you be more specific? Lol

 

[jaydub5]

FOXCAT... What did you have for breakfast?!
So, what is the best way to achieve better battery life? Why would letting the battery run down to 5% instead of 10% be a negative if we are calibrating the battery meter?
Some posters swear letting the phone die or go to a low percentage helped achieve better battery life... Not true?
What about wiping the cache to remedy lag?
Thanks again... must read your post about 50 times!
FOXCAT, what do you do for a living? Techie of some sort I presume?

 

[FoxKat]

Wow. Can you be more specific? Lol

That's obviously a rhetorical question, no? LOL!

FOXCAT... What did you have for breakfast?!
So, what is the best way to achieve better battery life? Why would letting the battery run down to 5% instead of 10% be a negative if we are calibrating the battery meter?
Some posters swear letting the phone die or go to a low percentage helped achieve better battery life... Not true?
What about wiping the cache to remedy lag?
Thanks again... must read your post about 50 times!
FOXCAT, what do you do for a living? Techie of some sort I presume?

Grande Triple-shot Latte (actually I start every day with one - I have a Saeco Royal Professional Superautomatic Espresso and Coffee maker Amazon.com: Saeco 21103 Royal Professional Fully Automatic Espresso Machine, Silver and Blue: Kitchen & Dining)

The best way to achieve better battery life is a loaded question. For most, "better battery life" means lasting the longest time from full charge to when I am forced to charge again. That's not better "life", that's longer run-time (I'll call it endurance). You can only get out of the battery...most of...what is put in (Einstein, “Energy cannot be created or destroyed, it can only be changed from one form to another.”) Now, the problem is that once it's in, getting the most useful energy out becomes a daunting task. The BEST way to get it out is SLOOOOOWWWWLLLLYYYYY. Since the simple movement of electrons generates heat from friction, the more electrons you move and the shorter time you move them in, the greater the friction and the more usable energy is wasted in heat.

There really isn't anything you can do safely regarding charging or discharging the battery that will increase its endurance except charging to 100%. It will give what's asked of it until it has no more to give. The task of reducing consumption rates is one for the manufacturers. You can certainly make sure the meter is accurately representing the SOC during the discharge cycle, so you aren't complaining about a battery that you think has 15% left when in reality it has 30% but the meter is out of kilter. This is done by the process I mentioned earlier...Meter Training.

Now, to get greater "life" out of the battery (here we mean lifespan, i.e. how long before the battery won't take sufficient charge to be useful - that 1.5 - 2 year mark), you CAN positively influence that but is it really all that important and cost effective? Most people replace the phone long before the battery has lived its useful life. Also, how you do it may not be appealing as it means reducing the periods of time you require it to perform. In other words, charging to 100%, and then using to 10% and then recharging to 100% will put your battery through far more stress over time, thereby reducing its lifespan than if you charge to 80%, use to 20% and then charge to 80%. In fact, if you charge to 70%, use to 30% and charge to 70%, you will most likely more than quadruple its expected lifespan (500 cycles of 100% charge). But who is going to do this...nobody.

There is an easier way to accomplish a positive impact on the battery's lifespan. Simply plug in to a power source pretty much whenever its available. If in the middle of the day you are at your work desk, plug into the USB port of the computer. It's far more healthy for a LIPO battery to be charged multiple times over the day but in shorter bursts, and during the middle of the discharge cycle than it is to charge anywhere near 100%, or discharge anywhere near 0%.

Letting the phone discharge to below 10% is obviously going to give you longer run-times, simply because you are using more of the energy you've stored in the vessel. Unfortunately the chemistry of the battery doesn't particularly "like" having to stress itself to dump the last usable power, and so it "ages" the battery's internal components and shortens its lifespan dramatically. Letting it "die" (power off automatically at 0%), you run the risk that the meter is improperly calibrated and the battery could be deep-discharging. The potential result is the "White light of Death" I mentioned before...the battery ceases being responsive to the charger and refuses to recharge. It has happened to far too many people to be a figment of anyone's imagination.

Wiping cache to reduce lag may be an effective way of regaining some control over the phone, due to becoming "junked up" with garbage running in the background or fragments of apps that have long since been deactivated. Still, Android is supposed to handle that for you. I almost never wipe the cache, and only do so when flashing ROMs. A cache is simply a temporary holding tank for a wide range of tiny, small, medium and sometimes large code fragments that are used frequently by the OS. They are written initially by the OS, and for the most part remain static. Some things are overwritten by the OS, but as long as the phone hasn't suffered an electromagnetic event from a nearby thermonuclear bomb explosion, its likely to not have any errors in the cache, and so all you're doing when wiping is removing code which will simply be replaced with the same code again once the phone is restarted.

I am a Mortgage Banker by day, Artists Management Company owner on the side, and Android enthusiast 24/7/365. I also LOVE helping people and so I get my own gratification by making the personal Android experiences of others more rewarding. So you could say, I do it because I'm selfish...sorta... :biggrin:

 

[jaydub5]

A big THANK YOU is in order. FYI, since you are a Get Smart fan, I have met Barbara Feldon
(along with her husband) here in NYC numerous times, and she is still beautiful and very nice as
well.
Good night... down to 13%, replacement phone,, shutting off and recharging for the first time.
One question: Does using the phone while it is
charging damage the battery? My guess, as more heat is produced, would be yes...

 

[FoxKat]

A big THANK YOU is in order. FYI, since you are a Get Smart fan, I have met Barbara Feldon
(along with her husband) here in NYC numerous times, and she is still beautiful and very nice as
well.
Good night... down to 13%, replacement phone,, shutting off and recharging for the first time.
One question: Does using the phone while it is
charging damage the battery? My guess, as more heat is produced, would be yes...

Barbara Feldon = yummy.

Using (or even simply being on) while charging doesn't necessarily damage the battery, but can cause the charger and meter to have difficulty reaching a full charge. The way the meter determines the charge is complete is to watch for a signature drop in current draw coupled with a specific pattern in voltage changes. The phone is pulling current and in varying amounts while in operation. It's these varying current draws that will confuse the meter and can cause it to misinterpret a voltage change as a result of the phone, and instead conclude that the battery has reached the end of the charging cycle. This is why it's said the only way to assure a complete charge is to do it with the power off. This is the reason the manufacturer specifies that the first charge should be with power off.

Sent from my DROID RAZR using Tapatalk 2