Your battery gauge is lying to you (and it's not such a bad thing)

[theotrman]

Thank you OP for sharing! Great read, that any novice can understand !

 

[Ajju^]

Hey guys as u can see the ss m getting some sudden drops this usually happens after 30% while screen is off i did try to calibrate my battery 3-4 times but it didn't help anything else i can try?

Sent from my Moto G 2014 using Tapatalk

 

[JimmyRay]

Great read, thank you for the clear explanation!

As this article was written over five years ago, I'm wondering if there have been any changes in battery technology, or the way batteries are monitored in Android/CM?

By the way, I was informed of this thread after querying the 10% drop from full-charge in this post. While I certainly appreciate the detailed explanation, I have seen battery usage screenshots from some users showing a steady decline from full charge - is this simply a case of different phones (OSs?) implementing varying battery monitoring techniques?

Thanks again!

 

[martefromocr]

My LG G3 doesn't think this way. When i unplug the phone it stays at 100% for such a long period of time, even if i use it for half an hour. Don't know why.

 

[tet-bundy]

Nice OP!

Gesendet von meinem unknown mit Tapatalk

 

[vivithemage]

Cool, makes sense

 

[nickyip123]

My LG G3 doesn't think this way. When i unplug the phone it stays at 100% for such a long period of time, even if i use it for half an hour. Don't know why.

Mine too, though it's not LG G3...
I guess it's because that 100% battery mark is actually something like 95% battery mark for real?

 

[M Huzaifah]

Very informative. Worth reading.

 

[anwaypasible]

'How could the rate of depletion be increasing over the first 5 hours while the rate of current draw is relatively steady? And why does the projected battery line separate from the reported levels, but then exactly mirror the later rises and falls?'

because the battery uses lithium ions rather than lithium eons - it causes a ratio to exist because the fact that it is an ion categorizes it as something that isn't meant to be out of it's sterile home environment.
every contact is corrosive & because the ratio exists, it isn't linear but instead logarithmic.
such is, it also holds true about the battery being plugged in & those points of corrosion being healed by the charging & that is how the battery can mirror 'the later rises and falls'.
because you see, if there's corrosion inside - it can be reactive enough allowing all of the particles to move around with an adjustment until the corrosion is either shoved to a corner furthest from the inlet , shoved to the corner closest to the inlet & healed .. or whatever corrosion is seen while charging gets repaired as if using a system scan to replace damaged operating system files (but only the programs not in use can be accessed).

the whole updating battery technology will serve as true about all that corrosion making it's way to a corner to be healed & showing a 100% completion for process one , but then needing the charger to switch from rotating the corrosion into place onto repairing the corrosion itself.
people who enjoy spreadsheets will be quick-served about how there's a process of adaptability & adopt-ability .. because if the person needs to use the battery sooner rather than later - the phone might be entirely unusable if there's enough corrosion that needs to be healed. - might as well say the circuit traces leading into the battery are broken & a train that is expected to roll on tracks just doesn't have any tracks to roll along on & there isn't any rolling it along something else (saving that for the future generation of batteries after this one).
and then after that, the power to draw in healing while drawing out to find what needs healed at the same time.
because once that one is known forwards & backwards (basically happening twice), then it can be shut & closed as though a period.
because then from there, the phones can run on the electricity coming from electrical cords in the walls or power lines on the sides of roads or signals from cell towers or other wireless devices (think of the wireless chargers, but with a whole landscape of spreaded use - comparable to a color television screen where rather than all the colors necessary in the air, it can run off of just one needed component such as luma (or the color of white light for example) to get the whole assembled ball rolling.
(then we'd need batteries 'just in case' the outside source of power went out or needed a repair)

alkaline batteries didn't have the ability to plug them in & repair the memory affect .. at least not on the consumer level & the professional level needed extremely strict guidelines or 0.000000(whatever number) off is all it took to go from a normal working battery to one that needs tossed out because it can infect any other battery it comes into contact with while not performing 100% (and the farther from 100% = the worst the virus spreading from one battery to the next).

the real only point of arguing is which level are we at here & today right there with our hands on it .. otherwise the walking dead returns with a new season this month on october 23rd.

(how does the battery & charger rotate the particles you ask? magnetically is all - easy because it was engineered to do it & works the same way as some complicated scene of walls moving such as in harry potter times with labyrinths & scenes of people walking on stairs that are upside down on the ceiling - either the phone, the battery, the charger, or a combination of all three hold what the battery is supposed to be magnetically & will ruthlessly & brutally go for the battery the same way magnetically each time until one of the pieces in the equation changes & then things grow either worse or improved (or you found the same thing in another product))


as far as bump charging goes - it's simple .. if the way lithium ion works is reliant on contact with the charger to keep the corrosion inside low to continually allow the rotation of particles in order for the healing to happen, then tapping the charger back on each time the phone drops to any number lower than 100% is going to accelerate the needing to buy a new battery sooner rather than later.
because there's the 80% margin that is a vital number to lithium ion batteries (as has been said in battery care guides|articles), touching base with that percentage only magnifies the problem of the corrosion.
so turning the charger on at say 90% is well enough away from 80% .. but also not near 99% causing excessive contact of the ions lowering the longevity of the battery (because of corrosion probability that goes beyond the scope|reach|capability of a consumer charger) .. easily makes sense why the battery isn't totally at 100% when you take the phone off the charger & the percentage drops fast at first.
& it needs to be said, because otherwise there's somebody in there keeping the rate of battery usage linear with the graph & potentially getting illicit work done without the knowledge of the phone user.

it really isn't about battery 'charge' more than it is about battery 'condition' - as they are two separate values that are both necessary.
see, you can have a battery that is 98% charged, but it's condition is at a point where that is literally the last charge ever for the battery.
or mix it up some with the battery being not charged any, but the condition of the battery has room for an opportunity to be charged 1,000 times in the future.

those guides tell you to do a full charge only once a month & that means only bump charge it once a month.
(if you are a speed racer - try bump charging after every battery drain that goes to 0% & see if that ion finally kicks in for it's intended lack of memory affect or if all that did is cause the battery to refuse to hold a charge faster - because it is either one or the other ; unless you are using an ion twice & then the battery won't be any good for some off the wall (or shelf) refurbisher to help the battery (or did two circuit boards with an interface cable become one to once again be 'off the wall' & trumped my words? lol)

 

[Thespartann]

I realize that much of this is common knowledge on XDA. Still, every day I see people post about how their phone "loses" 10% as soon as it comes off the charger. I also have friends who can't understand why their battery drains so quickly. Trying to explain this to people without hard numbers is often met with doubt, so I figured that I'd actually plot it out with real data.

So it's not a piece that is optimized for this audience, but I hope that you find it interesting.


--------------------------------------------------

Your Smartphone is Lying to You
(and it's not such a bad thing)

Climbing out of bed, about to start your day, you unplug your new smartphone from its wall charger and quickly check your email. You've left it plugged in overnight, and the battery gauge shows 100%. After a quick shower, you remember that you forgot to send your client a file last night. You pick up your phone again, but the battery gauge now reads 90%. A 10% drop in 10 minutes? The phone must be defective, right?

A common complaint about today's smartphones is their short battery life compared to older cell phones. Years ago, if you accidentally left your charger at home, your phone could still make it through a weeklong vacation with life to spare (I did it more than once). With the newest phones on the market, you might be lucky enough to make it through a weekend.

And why should we expect anything else? Phones used to have a very short list of features: make and receive phone calls. Today we use them for email, web surfing, GPS navigation, photos, video, games, and a host of other tasks. They used to sport tiny displays, while we now have giant touch screens with bright and vibrant colors. All of these features come at a cost: large energy requirements.

Interestingly enough, improvements in battery management technology have compounded the average user's perception of this problem. Older phones were rather inelegant in their charging behavior; usually filling the battery to capacity and then switching to a trickle current to maintain the highest charge possible. This offered the highest usage time in the short-term, but was damaging the battery over the course of ownership. As explained at Battery University, "The time at which the battery stays at [maximum charge] should be as short as possible. Prolonged high voltage promotes corrosion, especially at elevated temperatures."[1]

This is why many new phones will "lose" up to 10% within a few minutes of coming off the charger. The reality is that the battery was only at 100% capacity for a brief moment, after which the battery management system allowed it to slowly dip down to around 90%. Leaving the phone plugged in overnight does not make a difference: the phone only uses the wall current to maintain a partial charge state.

To monitor this, I installed CurrentWidget on my HTC ADR6300 (Droid Incredible), an app that can log how much electric current is being drawn from the battery or received from the charger. Setting it to record log entries every 10 seconds, I have collected a few days worth of data. While many variables are involved (phone hardware, ROM, kernel, etc) and no two devices will perform exactly the same, the trends that I will describe are becoming more common in new phones. This is not just isolated to a single platform or a single manufacturer.

Chart 1 shows system reported battery levels over the course of one night, with the phone plugged in to a charger. Notice that as the battery level approaches 100%, the charging current gradually decreases. After a full charge is reached, wall current is cut completely, with the phone switching back to the battery for all of its power. It isn't until about two hours later that you can see the phone starts receiving wall current again, and even then it is only in brief bursts.



The steep drop in reported battery seen past the 6.5 hour mark shows the phone being unplugged. While the current draw does increase at this point (since the phone is being used), it still cannot account for the reported 6% depletion in 3 minutes. It should also be obvious that maintaining a 100% charge state is impossible given the long spans in which the phone is only operating on battery power.

Using the data from CurrentWidget, however, it is quite easy to project the actual battery state. Starting with the assumption that the first battery percentage reading is accurate, each subsequent point is calculated based on mA draw and time. Chart 2 includes this projection.



Now we can see that the 6% drop after unplugging is simply the battery gauge catching up with reality.

The phone manufacturers essentially have three choices:
1. Use older charging styles which actually maintain a full battery, thereby decreasing its eventual life
2. Use new charging methods and have an accurate battery gauge
3. Use new charging methods and have the inaccurate battery gauge

Option one has clearly fallen out of favor as it prematurely wears devices. Option two, while being honest, would most likely be met with many complaints. After all, how many people want to see their phone draining down to 90% while it is still plugged in? Option three therefore offers an odd compromise. Maybe phone companies think that users will be less likely to worry about a quick drop off the charger than they will worry about a "defective" charger that doesn't keep their phone at 100% while plugged in.

Bump It. Or Should You?

One technique that has gained popularity in the user community is "bump charging." To bump charge a device, turn it off completely, and plug it into a charger. Wait until the indicator light shows a full charge (on the ADR6300, for example, the charging LED changes from amber to green) but do not yet turn the device back on. Instead, disconnect and immediately reconnect the power cord. The device will now accept more charge before saying it is full. This disconnect/reconnect process can be repeated multiple times, each time squeezing just a little bit more into the battery. Does it work?

The following chart plots battery depletion after the device has received a hefty bump charge (6 cycles) and then turned on to use battery power. Note that the system does not show the battery dropping from 100% until well over an hour of unplugged use, at which point it starts to steadily decline. Again, however, it should be obvious that the battery gauge is not syncing up with reality. How could the rate of depletion be increasing over the first 5 hours while the rate of current draw is relatively steady? And why does the projected battery line separate from the reported levels, but then exactly mirror the later rises and falls?



The answer, of course, is that bump charging definitely works. Rather than anchoring our projected values to the first data point of 100%, what happens if we anchor against a later point in the plot?



Aligning the data suggests that a heavy bump charge increases initial capacity by approximately 15%. Note that the only other time that the lines separate in this graph was once again when the phone was put on the charger and topped up to 100%. Just as with the first set of graphs, the phone kept reporting 100% until it was unplugged, dropped rapidly, and again caught up with our projections.

So what does it all mean?

If you absolutely need the highest capacity on a device like this, you will need to bump charge. There are currently people experimenting with "fixes" for this, but I have yet to see one that works. Be warned, however, that repeated bump charging will wear your battery faster and begin to reduce its capacity. If you are a "power user" who will buy a new battery a few months from now anyway, this presumably isn't a concern. If you are an average consumer who uses a device for a few years, I would recommend that you stay away from bump charging. The bottom line is that you don't really "need" to do it unless you are actually depleting your battery to 0% on a regular basis.

If you are someone who can top off your phone on a regular basis, do it. Plug it in when you're at home. Plug it in when you're at your desk. As explained by Battery University, "Several partial discharges with frequent recharges are better for lithium-ion than one deep one. Recharging a partially charged lithium-ion does not cause harm because there is no memory."[2]

Beyond that, the best advice I can offer is to stop paying such close attention to your battery gauge and to just use your phone. Charge it whenever you can, and then stop obsessing over the exact numbers. If you really need more usage time, buy an extended-capacity battery and use it normally.

Thanks for the guide

 

[DoktorPlazarus]

How would I go about figuring why my OnePlusbe6t won't charge past 97% to get a full charge

Sent from my OnePlus6T using XDA Labs