What is the fastest way to drain battery?

[weatherlover1]

Does it make me a geek that I read that whole post by FoxKat and found it quite interesting?

 

[FoxKat]

Does it make me a geek that I read that whole post by FoxKat and found it quite interesting?

LOL! Am I to take that as a complement to me, or an observation of just how geeky we both are?!!

 

[SAVVY_1]

Run the flashlight...


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[FoxKat]

Run the flashlight...


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No, don't do that as it can destroy the flash LED. It wasn't designed to be run at full level current for more than a short period of time. If you want to discharge rapidly and NOT destroy the camera, download and install https://market.android.com/details?id=net.ujacha.deadpixel&feature=search_result, then tap on the screen till the display turns full WHITE. That draws more current and doesn't do harm.

 

[pinoy_92]

why cant i resist reading all these long posts....

as for the OP's question i found that streaming movies through wifi using motocast is the fastest way to drain the battery.

as far as i know, my pc was streaming at more than 1GB/s so yea it takes alot of battery on your phone. i guess streaming from netflix would do the same, but your gonna need 4g connection as well as unlimited data.

so you can use netflix or stream over your router. your call.

 

[SAVVY_1]

Thanks for the tips!

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[FoxKat]

why cant i resist reading all these long posts....

QUOTE]

Looks like myself and weatherlover1 aren't the only geeks.

 

[areuling1]

I don't even own a razr and I just read this whole thread. I learned more about batteries in the past 20 minutes then in the previous 25 years of my life. Just wanted to say thanks for the info

Sent from my Droid2Global using Tapatalk

 

[FoxKat]

At any rate, thank you all for your suggestions on how to drain the battery. Unfortunately (LOL), these methods did not work. So far my total up time since battery charge is 1 day, 6 hours...and I'm still sitting at 40% charge. My screen has been on for 6 hours 44 minutes. I streamed some HD videos over 4G, used my phohe as a 4G hotspot for 2 hours, had my daughter play several games, left the screen on full brightness...all to no avail. This is really funny - I'm having a hard time wearing down the battery! I guess it's a good problem to have.

Anyway, I'm just going to let it slowly run down through the day (and maybe into the next day and the next day). LoL

OK folks, here's another long one...if you can't take it, hit your back button now!

And here goes the reasons for the above...

Another phenomenom of Lithium Ion batteries is that the voltage doesn't drop very much during the bulk of the discharge cycle, but instead uses up the stored current (mA). Only when the mA reaches near empty does the voltage begin to drop rapidly, which is the reverse of the charging process (see the chart in my earlier post). Since mA can't be measured as a volume, but only as a flow (think of measuring water flowing through a hose, but you don't know how much water is in the reservoir to which it's attached), it can't be used to determine remaining capacity. So using the voltage alone as a measurement of the remaining stored charge is a highly inaccurate.

"While lead acid batteries have a gradual voltage drop on discharge, nickel- and lithium-based batteries tend to be flat and SoC (state-of-charge) estimation by voltage is difficult.
The discharge voltage curves of Li-manganese, Li-phosphate and NMC are very flat, and 80 percent of the stored energy remains in this flat voltage profile. This characteristic assists applications requiring a steady voltage but presents a challenge in fuel gauging. The voltage method only indicates full charge and low charge and cannot estimate the large middle section accurately."


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So, even though the phone thinks it has 40% if using the voltage as the only indicator, it may very well have 70% or 20%, but either way, at 3V it will read 0%. In other words, in order to determine capacity, you have to know many variables. Since the phone's charging circuit and battery meter knows one of those variables, the minimum voltage when it has to cut off the charging, and it also knows what the maximum voltage SHOULD be, probably pegged at 4.2V, what else does the charger and meter need to know?

Well it also knows what the "RATED" capacity of the battery is...3,300mA. Then it knows how much current it is pulling, because it is constantly monitoring current draw, so now we have as many as 4 knowns - voltage minium and maximum current capacity. You'd think that with that information and then if you factor in the constantly monitored current draw, that it would be simple to determine at what percentage the battery is after a known number of mA had been pulled. The problem with using those four variables to map out a metering of the current usage is that two of those variables are potentially inaccurate.

In the case of the maximum, if the charging cycle wasn't completed properly then the information plugged into that variable is wrong. Then there is the maximum capacity...that is - maximum "RATED" capacity. It is known that LI batteries lose capacity to hold a charge over time, and their maximum capacity is only there on the day it's manufactured. From that moment on, it is less and less. By the time 3 years have gone by, the battery may not even hold 70% of its original "rated" capacity. And then there's the charging process and if it is flawed, the actual capacity can go down quicker simply due to stressing the battery by charging incorrectly. So, using that for the formula will for all intents and purpose will ALWAYS produce wrong results, except for on the day of manufacture.

So where do we go from here? Well, the manufacturer of the phone knows all this (surprised??? LOL!) Since Motorola knows all this and more, probably including more about your own phone usage habits than even you know, they have likely engineered an algorythm that does what is known as a running or moving average, not too different than my car's MPG gauge. It would likely essentially learn how long it takes to fill up as well by watching the rate of current draw during the charging cycle, and also the point which the uses that information to help it determine what the present maximum "capacity" is rather than using the rated capacity, then works that into its algorythm.

"A more advanced method to measure SoC is coulomb counting. The theory that goes back 250 years when Charles-Augustin de Coulomb first established the “Coulomb Rule.” It works on the principle of measuring in and out flowing currents.

Coulomb counting experiences errors as well. For example, if a battery was charged for one hour at one ampere, the same amount of energy should be available on discharge. This is not the case. Inefficiencies in charge acceptance, especially towards the end of charge, as well as losses during discharge and storage reduce the total energy delivered and skew the readings. The available energy is always less than what had been fed into the battery. For example, the energy cycle (charging and then discharging) of the Li-ion batteries in the Tesla Roadster is about 86% efficient.

As with any numeric integration technique, coulomb counting accumulates error over time, which the modern fuel gauge tries to correct using voltage curves. Since these voltage curves harbor inaccuracies themselves, especially as the battery ages, the accuracy will continue to degrade over time."
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So then it would likely use not just one charging cycle, but several in a running total to watch the trends of charge and discharge (and voltage curves), so the results will be a closer "average" rather than a flawed estimate based on wrong variables. With each new charging cycle, the new data is added and the older data is deleted, so that the average becomes a moving average. My car does this over several tanks of gas. Since it doesn't know if I actually fill the tank every time, and also doesn't know at what point I'll consider it empty and decide to fill the tank again, it tries to come up with an MPG but instead of using one tankfull, it will average the consumption of several tankfuls and will adjust the average with each new refill - whether filled or I add only $20.

Unfortunately the errors over time will need correction. In the case of the phone, the way they will help to resolve those errors is by using the charging process and charge cutoff trends to identify the maximum capacity, and this can overcome some of the error. And then the results are supplemented with flagging of the full charge state by charging while powered off. Still, it's not a perfect science, so there are even newer techniques being developed.

The Adaptive System on Diffusion (ASOD) by Cadex features a unique “Learn” function that adjusts to battery aging and achieves a capacity estimation of +/-2% across 1,000 battery cycles, the typical life span of a battery. The SoC estimation is within +/-5%, independent of age and polarization. ASOD does not require outside parameters; it is self-learning. When replacing the battery, the learned matrix will gradually adapt to the new battery through use and achieve the previous high accuracy again. Researchers are exploring new methods to measure battery SoC, and such an innovative technology is quantum magnetism (Q-Mag™).

Q-Mag by Cadex does not rely on voltage or current flow but it looks at magnetism. The negative plate on a discharging lead acid battery changes from lead to lead sulfate, which has a different magnetic susceptibility than lead. A sensor based on a quantum mechanical process reads the magnetic field through a process called tunneling. Figure 3 compares the magnetic field response of a fully charged battery to one that is 20% charged. A low battery has a three-fold increase in magnetic susceptibility compared to one that is fully charged."

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Why am I going into all this? Because for every shred of evidence that can be produced to show that something is accurate regarding battery charge levels, there's going to be someone else who will work to reach a greater level of accuracy. But at the end of the day, does it REALLY matter for our little phones? Why not simply use it and charge it when we can? It doesn't hurt the battery to charge it in 10% increments 10 times to get to 100%, and it doesn't count as 10 charging cycles, but a collection of 10%s =100%, or one charging cycle. So if you start at 100%, use 60%, charge it 40%, use 50%, charge it 20%, use 30%, charge it 50%, and use it 20%, charge it 50%, use it 60% and charge it 40%, you would used essentially 220%, would have ended up at 80% and it would count as only 2 charging cycles (40+20+50+50+40=200/2=100%).

It is actually more beneficial to use the battery that way than it is to charge fully, use 100%, charge fully, use 100%, and charge fully, and use 20% to get to the same point. In the second example, it will give the same results, but what WILL change is how long the battery will last over its life, and in the latter example it will not last as long.

"Table 2 compares the number of discharge/charge cycles a battery can deliver at various DoD levels before lithium-ion is worn out. We assume end of life when the battery capacity drops to 70 percent. This is an arbitrary threshold that is application based.

Depth of discharge​	Discharge cycles​	Table 2: Cycle life and depth of discharge A partial discharge reduces stress and prolongs battery life. Elevated temperature and high currents also affect cycle life."
100% DoD 50% DoD 25% DoD 10% DoD​	500 1500 2500 4700​

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So in the chart above, it seems that a 50% discharge cycle produced 75,000% life (1,500 cycles of 50%), whereas a 100% discharge cycle only resulted in a 50,000% life (500 of 100%) and a 25% cycle resulted in a 62,500 life (2,500 of 25%). This means that the sweet spot in the above chart seems to be 50%. Unfortunately it doesn't show greater precision so the real sweet spot could be 60% or 70%???

It stands to reason that if 100% cycles result in 33% shorter life than 50% cycles, and even results in 20% shorter life than 25% cycles we'd all benefit from charging more frequently, but not too frequently.

 

[FoxKat]

I don't even own a razr and I just read this whole thread. I learned more about batteries in the past 20 minutes then in the previous 25 years of my life. Just wanted to say thanks for the info

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You make all my efforts worth while! Thanks!

 

[bamorris2]

Thanks for all of the great info on batteries...more than I ever wanted to know!

I was finally able to discharge the battery to the point that the phone powered off. But I noticed that this phone is unlike my previous cell phones. In the past, phones would typically shut off at around 5% capacity. But this phone went all the way down. In fact, it still stayed on for another half hour streaming NFL once it reached 2%!!! Then it went to 1% and stayed on for another half hour or so. Finally, it gave up.

Anyway, just wanted to update everyone. This was probably a useless challenge to go through, but oh well. Now I know that my phone has an awesome battery. It took 2 days of heavy use to get it to die.

 

[SallyC]

Does it make me a geek that I read that whole post by FoxKat and found it quite interesting?

Absolutely! Join the club - I love his posts.

 

[weatherlover1]

Very interesting! I admit I don't get the fascination with perfect battery life. Yes I admit I do want to unplug my phone around 7am use it like I want to use it(which is probably mild compared to a lot of people on here) not having to turn all my notifications and widgets off(I got the phone for all that stuff ) and get it to as close to bed time as I can(11pmish) now if I talk for 4 hrs in a day I would expect its going to need charged good grief. I also plug it into the car charger when I am using GPS. I just don't like using it average(texting some surfing) and having 30% at 5pm. Hence why I loved my droid X and now can't wait to get my Maxx. From the sounds of this thread I will have no issues surfing the web some and making phone calls and making it to bed time on one charge. If your going to watch a crap load of movies etc good but your battery is going to drop yet it sounds like this phone is awesome 3300 is pure sweetness!! Yes like the next person I want to get the best battery life out of my phone as I can but I also know its a electronic device that is a small computer that can make phone calls and that take power and honestly I think they get dang good battery life considering what all they do in a day!

 

[jpcalhoun]

....The second solution will assure the meter is properly calibrated to what is a "FULL" charge for that battery in that point in its life, and when the voltage reaches the threshold for cutoff, the meter will then know what the range is. If you really need to know what the full range is, then a full charge is required, but it MUST be a FULL CHARGE, and that means while the power is OFF. Also a full discharge isn't absolutely necessary, since the charging circuitry already knows what voltage a full discharge is. If after a full charge it says to plug the phone in at 15%, you can be relatively sure it's not at 30%, and also relatively sure its not at 5%. It may be at 20% though not likely, but does it really matter all that much?

Sources for some of the information...Charging Lithium-Ion Batteries and other related articles from the same site.

Sources for other information range from RC sites to Wikipedia, to my own testing *(which I then verify with the above sources)*.

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Holly Smokes FoxKat :yeahbaby01:

 

[jpcalhoun]

Does it make me a geek that I read that whole post by FoxKat and found it quite interesting?

Absolutely...join the crowd:icon_ banana: