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Hi all!
I was browsing through Samsung Galaxy S's Android Development Section when I saw this:
"11. Do NOT overcharge
--Why, when, where: Almost all new batteries have an overcharging protection. This means that the protection that is built into the battery will not let it charge to 100%. This is a feature, not a bug! This will help prolong your battery life while also keeping it safe from overheating/explosion/etc. Do not try to trick it and unplug and plug again until you see 100%, just get used to the fact that you can't have 100% battery anymore and live with it, or you risk destroying your battery."
posted by user "shantzu"
here:http://forum.xda-developers.com/showthread.php?t=939752
I did "calibrate" my battery many times lately by unplugging it when charging and the replugging it. But I sure know I wont do it anymore! It's your choice whether or not you wanna do it!
I just wanted you to know this! Hope I've been helpful!
Cool story bro
Sent from my Dell Streak using XDA Premium App
pgill34 said:
Cool story bro
Sent from my Dell Streak using XDA Premium App
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+1, blablabla (sorry msg needed to be +10 characters, but it's more now and more and more and more )
eXtink said:
+1, blablabla (sorry msg needed to be +10 characters, but it's more now and more and more and more )
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I didnt say this. I just quoted and I said that I wont charge my phone to 100% with the plug-unplug way. So if you take my advise do so, if you don't want to take it please stop posting ****!
vladstercr said:
I didnt say this. I just quoted and I said that I wont charge my phone to 100% with the plug-unplug way. So if you take my advise do so, if you don't want to take it please stop posting ****!
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I dont think he was posting ****. He just wanted to post "+1" (as in "me too"), but needed to respect the minimum character limit for a post.
Badly worded, but it doesnt look like he was making fun of you or anything.
Sent from my Milestone using Tapatalk
I love this thread already
Isn't calibrating the battery all about fixing an Android bug?
Anyway, this reminds me, the Milestone overstates the full charge mV and underestimates the low battery mV.
So, if Battery Monitor Widget reports that I have 4230mV when it's fully charge and plugged in... it's really only 4170mV.
When it's reporting empty at 3200mV, it's really at 3300mV.
http://www.android-hilfe.de/root-ha...ku-infos-ladekurven-leistungsverbraucher.html
Externally measured or indication of the internal voltage measurement
3.30 volts / 3.20 volts
4.12 volts / 4.18 volts
That is, the stone over-estimated the voltage at the battery is full by ~ 60 mV and underestimated the power of up to 100 mV with an empty battery. The intent is well-battery protection (which is good too). It is pretended that 3.0 and 4.2 volts to discharge until it is loaded. In reality, there are more 3.1 volts and 4.15 volts (which by the way of battery manufacturers also better unanimous opinion!).
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Apparently, we are still protected even if we do calibrate the battery.
I'm pretty sure that Payce at android-hilfe actually took that battery out of his phone so I'll go with that.
Thanks for sharing
Good article
Over charging doesn't effect Lithium Ion batterys;
http://en.wikipedia.org/wiki/Lithium-ion_battery
DannyDroid said:
Over charging doesn't effect Lithium Ion batterys;
http://en.wikipedia.org/wiki/Lithium-ion_battery
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Gee thank you! I just wanted to start correcting this non-sense. The "overcharging" affects Lithium-Polymer batteries, not Lithium-Ion, so calibrating battery is HARMLESS!!!!
If you have a Samsung Galaxy S then you have this possibility.
I think we can close this thread.
Actually you can overcharge (any) battery, charging it to the higher voltages for higher capacity when used daily (as cell phones).
However it lowers total lifetime of the battery, but you can get more battery time.
But this isn't the cell phones' thing. IMHO charging circuit + circuits in battery won't allow you to do this. So you can't really overcharge.
This "calibrating" is even suggested by notebook manufacturers - you have to do full discharge -> full charge to set the voltage "limits" for 0% and 100%, so the battery indicator can estimate the remaining battery % precisely.
Just few quotations from http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries to support my opinions:
"In terms of optimal longevity, a charge voltage limit of 3.92V/cell works best but the capacity would be low."
"Should I disconnect my laptop from the power grid when not in use? Under normal circumstances this should not be necessary because once the lithium-ion battery is full, a correctly functioning charger will discontinue the charge and will only engage when the battery voltage drops to a low level."
"Partial discharge on Li-ion is fine; there is no memory and the battery does not need periodic full discharge cycles other than to calibrate the fuel gauge on a smart battery."
The milestone has a Lithium-ion polymer battery which looks like they do suffer from over charging.
"It is important to note that trickle charging is not acceptable for lithium batteries; Li-ion chemistry cannot accept an overcharge without causing damage to the cell, possibly plating out lithium metal and becoming hazardous.[5] Most manufacturers claim a maximum and minimum voltage of 4.23 and 3.0 volts per cell. Taking any cell outside these limits can reduce the cell's capacity and ability to deliver full rated current.
Most dedicated lithium polymer chargers use a charge timer for safety; this cuts the charge after a predefined time (typically 90 minutes)."
http://en.wikipedia.org/wiki/Lithium-ion_polymer_battery
Someone will have to dig deeper into the OEM charger to see if it has some sort of cut off.
the thing with timer seems pretty weird to me. Try charging your battery with very little current - why should you cut it off after 90 minutes? Makes no sense to me, but I'm not an engineer so there may be a fact I overlook.
At the same time with noting overcharge will damage battery cell you should point out that there is no way to overcharge the battery without charging the battery CELLS itselves (not whole battery pack with its circuitry) with your custom charger without monitoring voltage/current.
However - yes, you're right, battery cells can be damaged.
I assume it would be the charging unit itself (i.e. the plug) which as the 90min cut off.
Charging via a USB takes ages (supplied at 5V) and without the "plug" it prob wouldn't have a cut off so the chances of over charging would be higher but would require leaving it in for longer.
I'm not sure, I'm only a first year electriton and haven't touched on batterys.
DannyDroid said:
Charging via a USB takes ages (supplied at 5V)
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The "plug" is just 230V~ -> 5V- transformer so the only difference is current, supplied voltage is the same. Btw I leave my phone in cradle for extended periods of time (24h+) and nothing bad happened. When it's at 100% it stops charging so I don't expect anything to happen.
Same with notebooks - it charges to 100% and stops. E.g. HP does stop charging until battery level drops to 90% so it won't "trickle charge" or do many 99%->100% cycles. Dunno how does the phone charging work, because it says 100% all the time. This can be possibly a bad thing
My Droid 4 appears to charge to over 4.3V. Yikes!
Reported by Battery Monitor Widget Pro: 4.317V (pretty sure I saw 4.351V one time but I don't know how BMW calculates/reports voltage)
Measured with Fluke 88V across battery terminals: (drat...are there convenient probe contacts? didn't find anything obvious without deconstructing it)
Found this for the Nexus Galaxy
http://forum.xda-developers.com/showthread.php?t=1507528
Anything like this for the Droid 4? an app (root)?
It appears some sort of battery management boots when the phone is plugged in while turned off? Just curious since I always leave my phone on.
My past 3 smart phones I've kept for 3 to 6 years each. With the non-removable battery in the Droid 4 I'd like to find something to extend it's life.
I figure Motorola went with the lightest smallest battery that would power the thing for the better part of a work day and last for the average user's retention time for a phone (1 year? maybe 2?). It appears they are overcharging the battery to squeeze some extra capacity out of it. Greatly reduces the usable battery life but still meets the design criteria. I'd rather go with something like 10% - 90% charge cycles and double or (more likely) triple the life of the battery.
Right now I'm using Battery Monitor with the max voltage alarm but that means you have to be there to hear the alarm and unplug from the charger. Not really practical.
Since I mostly charge at home I'm considering wiring up a usb cable for my ElectriFly RC charger but that's not as convenient or flexible.
For reference, the following are excerpts from Battery University:
http://batteryuniversity.com/learn/article/charging_lithium_ion_batteries
"Most cells charge to 4.20V/cell with a tolerance of +/–50mV/cell. Higher voltages could increase the capacity, but the resulting cell oxidation would reduce service life"
http://batteryuniversity.com/learn/article/the_li_polymer_battery_substance_or_hype
"Charge and discharge characteristics of Li-polymer are identical to other Li-ion systems "
http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries
"Most Li-ions are charged to 4.20V/cell and every reduction of 0.10V/cell is said to double cycle life. For example, a lithium-ion cell charged to 4.20V/cell typically delivers 300–500 cycles. If charged to only 4.10V/cell, the life can be prolonged to 600–1,000 cycles; 4.00V/cell should deliver 1,200–2,000 and 3.90V/cell 2,400–4,000 cycles. Table 4 summarizes these results. The values are estimate and depend on the type of li-ion-ion battery."
Charge Level (v) -- Discharge Cycles -- Capacity at Full Charge
---- [4.30] --------------- [150 - 250] -------------- [110%]
----- 4.20 ----------------- 300 - 500 ---------------- 100%
----- 4.10 ----------------- 500 - 1000 --------------- 90%
----- 4.00 --------------- 1200 - 2000 --------------- 70%
----- 3.92 --------------- 2400 - 4000 --------------- 50%
The Droid 4 uses a different kind of battery chemistry than most other li-ion batteries. You can read about it here on this Anandtech article on the RAZR (which uses the same chemistry, they didn't bother writing an article on the D4).
The interesting bit:
When I reviewed the Bionic, I made note of the device’s higher than normal Li-Ion voltage battery (3.8 V nominal) and later received word that this is actually a new Li-Ion battery chemistry that Motorola is adopting across its device line. We’ve now seen it in the Bionic, the Atrix 2, and thanks to some teardowns know that it’s inside the RAZR as well.
As an aside, people love to talk about how battery tech is going nowhere, but here we have a clear example of a few mass-market devices actually shipping with higher voltage batteries. Now that I know it exists, I want this in everything.
Interestingly enough, the sealed internal battery on the RAZR is 1750 mAh at 3.8 V (6.7 Whr) which is ever so slightly larger than the Bionic’s stock 1735 mAh at 3.8 V (6.6 Whr) battery. Like the Bionic, the battery has a thin profile and extends across almost the entire area of the device. We’ve now seen two different approaches to getting devices ultra thin: dual-sided PCBs that take up about a third of the areal profile (which is what Samsung and Apple do), saving the rest for a thick battery, and the Motorola approach with a single-sided PCB and a thin battery that extends over the entire area.
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Anyway, the point is that that what you're seeing is normal. If your D4 isn't charging to that voltage (which can happen if your battery stats gets screwed up), battery life can be ... disappointing.
Hope this helps!
podspi said:
Anyway, the point is that that what you're seeing is normal. If your D4 isn't charging to that voltage (which can happen if your battery stats gets screwed up), battery life can be ... disappointing.
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I agree that "normal" is "by design" but that's not what I want. I expect the designed duty cycle for the battery is less than 2 years.
I understand that charging to 90% will shorten time between getting on a charger but I can't go a whole day now anyway.
I plan to keep the phone for another 3, 4 or more years.
The battery or failure (worn out) is not covered under any of the warranty plans.
The battery is not removable and getting it replaced is probably not inexpensive (along with some probability of damaging the phone during replacement and probability of issues after).
My understanding is that (at least for now) upgrading or activating promotional equipment will cause me to lose my grandfathered $30 unlimited data.
Right now I usually charge in the morning, afternoon and late at night (phone stays on 24x7).
If I had something to limit charging to 90% unattended I would be leaving it on the charger over night and probably a couple of times during the day.
I am rarely away from a power source for very long. Charger at home, charger in the car, charger at work. Plugging in is not all that inconvenient.
If that triples the life of my battery that's HUGE.
The issue is leaving it on a charger unattended and having it stop charging at 90%.
[-deleted-]
Some more data:
http://forums.macrumors.com/archive/index.php/t-1429825.html
Another note:
These are 3.8V not 3.7V cells (100mV higher listed)
So, if you take your above chart and bump everything up by 100mV, 100% depth of charge is achieved at/around 4.3V (instead of 4.2V). I can believe a phone manufacturer would want to hit 100% charge if the cycles available are 300-500 (that's 1-2 years for 'average' users).
The info on that mac forum seems to indicate something about the 3.8V cells also having more available cycles, but that may be related to when they are used in stock configurations for the 3.7V cell (100mV less, double or better the usable cycle count).
Motorola is pretty good about covering their tracks and keeping things quiet (I worked on the communications equipment side of the pond for awhile) so finding spec's/data/charge curves for custom built batteries is going to be tricky. Easiest would be finding where they're getting them/re-branding and finding out exactly what they are.
Hope you can read Chinese
Brandon314159 said:
Some more data:
http://forums.macrumors.com/archive/index.php/t-1429825.html
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This is the problem... (unless I missed it following all those links in that post) I didn't see any real data other than a battery labeled "3.8V". That post kind of sums it up in closing with:
Given the evidence, I think we'll likely see a new battery chemistry in the next iPhone. However, this needs to be taken with a grain of salt, since we don't know if the 3.8V chemistry is what LG is using. Even if we find out that the new LG battery is 3.8V, that doesn't mean it's the same 3.8V technology we're seeing in the new iPhone. Since Apple loves to talk about their batteries, if it is featured, I think there's a good possibility they may talk about it. If they do, that could confirm they're using LG's tech. Still, if they're using a 3.8V battery, one must ask why Apple made the change if it didn't have some benefits in store for the new iPhone ultimately. It does, without question, at least confirm a new battery chemistry. The nominal voltages of batteries are directly related to the chemistry utilized within, so you wouldn't get 3.7V and 3.8V both using the exact same chemistry.
From the anandtech article: Most of the time, users quote battery capacity in just mAh because you can be assured that the nominal per-cell voltage of consumer grade lithium-ion batteries is going to remain the same, at 3.7 V nominal, and 4.2 V fully charged for a Lithium-manganese oxide (LiMn2O4) battery. That isn’t something that was just decided on; the voltage falls literally out of the electrochemistry of the reaction. Lithium is the ideal anode for an electrochemical cell because it has the lowest redox potential, at –3.05 V, and it’s very light, at 6.94 g/mol. Combine that with a cathode of your choice, and you get a battery. Relatively standard cathode choices are things like Mn2O4 or CoO2 or NiO2, with the first and second being popular choices. In reality, a graphite anode is used alongside a LiMn2O4 cathode to make things safer, and ions migrate between the cathode and anode during charge and discharge. I’ll spare you the hand waving, but the anode reaction gives you –3.0 V, the cathode reaction 1.15 V, combine them, and you get a ΔE of 4.15 V. You can see where the 4.2 V comes from purely from this, with a little bit of fudge factor. Each battery is different, but it’s again just a material choice.
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Still can't find any pointer to any "new chemistry" other than allusions to it... There hasn't been any new battery "chemistry" in years and I think that would be a really big deal. I'm sticking with the info in my first post for the time being. Especially the table at the bottom.
Lets look at it this way:
* charging to 4.3 V *
Right now, starting with a charged battery in the morning I have to put it on the charger about once during the day and it's pretty much done again at the end of the day. That's just sort of my average usage.
* charging to 4.1 V *
If I were to only charge it to 90% I would probably have to put it on the charger about twice during the day (and again at the end of the day) and I would approximately quadruple the usable number of charge cycles.
[i'm really bad at math...]
So I would be putting it on the charger 1.5 number of times to get a ~4x increase in the number of usable cycles?
I can deal with the inconvenience of an extra charge during the day for the added battery life before replacement is required.
I cannot deal with the inconvenience if each charge has to be attended (to unplug it when it reaches 4.1V)
Can someone do an app to cut off my charge at a configurable voltage?
You might have a look at this (not for the faint of heart):
http://www.researchgate.net/publica...e_Material_for_Lithium_Rechargeable_Batteries
Click "view" on the right when that page comes up.
It has more to do with chemistry than much else, but the basic premise is that by using certain cathode materials, stretching available capacity out of a Lithium Cobalt Oxide battery can warrant the higher voltage with less of an available cycle charges hit than you might think. They're talking about up to 4.5V in this article although they're admitting losses of available cycles at high voltages.
I just skimmed through it so if you're really curious, dig deep (I'm at work so limited).
I'm a chemistry major so take it with a grain of salt
Ok... that made my eyes bleed.
something about blah, blah ... increased stability up to 4.5v ... blah, blah, ...dual doping ... blah, blah, ...microwave heating for 25 minutes...
No idea if manufacturing it might cost more than the phone or if that is what might have gone into my Droid 4, or how quantify increased stability up to 4.5v in terms of increased cycles.
but yes, from what I can tell, it does look like someone made some sort of advancement in battery tech
Did anybody find an app to do this?
Hey all,
I've been experimenting with the rear 4-pin connector on the back of the droid 4 (pogo-pins for the inductive charging rear door)
Connected a current limited power supply to Gnd and Vin on the back of my Droid 4 (pin lower right = gnd, pin lower left = Vin) at 5.0V and I had charging occurring at a nice speedy rate. Screen showed charging, amperage was around 1500mA to start scaling down to 1300mA-1100mA as it reached full charge. It seems to pass through the Lithium Ion battery management circuity so appears to be a safe way to dump in lots of power. Obviously these pins are designed to pick up power from the rear inductive charging cover that Motorola produced, but I wanted to try just pure 5.0V power. It appears that it is not bypassing or defeating the battery temp/overcharging safety circuit but of course test at your own will in a safe environment. I personally noted that if the battery was 'warm' the charge rate was reduced to avoid overtemp. Also it would scale down as the on-screen-indicator showed it was reaching full charge.
I’m thinking of grabbing some extra rear covers and making up some drop-in charging stations or alternative inputs (like solar/etc.)
Nice to get away from having to charge on the USB Micro connector which appears to limit charging current and cause wear-and-tear.
This seems like a VERY good thing if someone was building an external battery pack that fit onto the phone (like the one for the iPhone)…you could power it on, charge via this connector, and shut it down whenever you liked. The power draw on the phone drops off massively once it is charged so if you started with a full charge, it could float the battery all the way to empty.
Time to experiment! My first build will likely be a drop-in docking station.
Again, for reference:
Bottom right (when viewing back, camera at the top):
Gnd is Lower Right – Nearest the microUSB connector
Vin is Lower Left – Opposite side from Gnd on the bottom row
Don’t hit it with too much voltage! I limited myself to about 4.8V and 1700mA max. I'd expect over-voltage on these pins could damage the battery management circuity and fry the phone. I was using a good regulated supply with meters.
Cheers,
This is awesome, thanks for this! Might have to play with a cover and done batteries at some point... Please let us all know how your experiments go!
Sent from my DROID BIONIC using xda app-developers app
I like the idea of an expanded battery very useful.
I have a small solar cell + battery to charge my phone by USB already.
That is bad ass. Post some pics of your first prototype
Sent from my DROID4 using xda premium
Great news, thanks for your time, man.
Just wondering but do you know what the other 2 pins are for?
I got one with a broken usb port for parts and am now wondering if I could use this to build a fix.
Most any (not all) Li-ion battery is rated for at least a 1C charge rate. So with a 1785 mAh Li-ion battery you should be able to safely charge at 1785 mA. The trade off is the faster you charge it the more you reduce overall battery life. For example (not real numbers) if the expected life of the battery is 500 charges (a charge is the amount of current to charge the battery from it's nominal voltage to fully charged and has no correlation to how many times you plug it into a charger) then charging it at 0.75C might increase it's life significantly to 750 to 1000 charges.
Note: the stock wall wart is speced at 850 mA at 5.1 V output (very odd that voltage...).
Brandon314159 said:
Nice to get away from having to charge on the USB Micro connector which appears to limit charging current and cause wear-and-tear.
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More likely it's the power supply. Most all PC usb ports put out 500 mA at 5.0 V. Most (USB) wall warts are rated at 1000 mA at 5.0 V.
What has me worried is that the phone appears to overcharge the battery to something like 4.317 V or even 4.351 V... I'm hoping this is just an error in the phone/app voltage reporting, but then again it could just be the way they get that 1785 mAh capacity from the battery. Overcharging the battery in this way could well be safe and would have the effect of increasing it's capacity, but it will significantly reduce it's life as well. You would not expect a Li-ion battery to be charged over 4.2 V and preferably something like 4.17 V
Can you use those pins to directly measure the battery voltage? I was going to measure mine directly to compare with Battery Monitor Widget reporting but decided I didn't want to remove the sticker from the back of the battery and I couldn't get a reading from the push pin contacts.
Quick7135 said:
What has me worried is that the phone appears to overcharge the battery to something like 4.317 V or even 4.351 V... I'm hoping this is just an error in the phone/app voltage reporting, but then again it could just be the way they get that 1785 mAh capacity from the battery. Overcharging the battery in this way could well be safe and would have the effect of increasing it's capacity, but it will significantly reduce it's life as well. You would not expect a Li-ion battery to be charged over 4.2 V and preferably something like 4.17 V
Can you use those pins to directly measure the battery voltage? I was going to measure mine directly to compare with Battery Monitor Widget reporting but decided I didn't want to remove the sticker from the back of the battery and I couldn't get a reading from the push pin contacts.
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- You cannot use those pins to measure battery voltage as they are an input to the charger... IE they do not tie directly to the battery. You would have to watch the battery voltage at the screws for the battery flex-cable mount.
- There are lots of notes about the battery voltage being 'high' by peoples viewpoints. If you search around, someone explains the difference in chemistry that the Droid 4 is using and that it does have a higher Vmax during bulk/absorption charge levels. I believe the summary was that it is a non-issue. They aren't trying to 'cheat' the battery into higher voltage for more cap...it's just simply how that chemistry wants to be charged. You'll have to google around to find it.
I am curious to see what sort of 'external' packs I can come up with and likely would limit my charging rate to 1200mA or so just to keep things 'happy'. I got slapped pretty hard over at droidforums by an admin and my post removed for this same info...glad to see the community here is more accepting of my discoveries. :cyclops:
-Also, the other two pins are data lines...not sure if In/out compatible but one is Batt Temp and the other is Communication (for determining battery type). The phone doesn't like having these pins futzed with (can cause reboots/lockups) so there is clearly something on the other end...but sounds like the protection is weak regarding input into the processor/etc.
Once I have my phone near a camera, I will photo my connection method/mods (no direct soldering in-case I have to warranty the phone for other issues). That gave me 6" pigtails of wire that I have hiding behind my cheap-o case right now waiting for proper connections (I exited through the speaker hole on the stock back cover).
Brandon314159 said:
I am curious to see what sort of 'external' packs I can come up with and likely would limit my charging rate to 1200mA or so just to keep things 'happy'. I got slapped pretty hard over at droidforums by an admin and my post removed for this same info...glad to see the community here is more accepting of my discoveries. :cyclops:
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which mod did this to u? what reason did he give to do that to u? just want to know... cuz that sounds really uncool
myfishbear said:
which mod did this to u? what reason did he give to do that to u? just want to know... cuz that sounds really uncool
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I don't wanna get anyone in trouble or piss peeps off. PM me if ya want more details.
It was pretty uncool, all things considered.
Oh well, happier here already!
you know what u should add is a resistor and a on/off toggle for safety
Brandon314159 said:
- You cannot use those pins to measure battery voltage as they are an input to the charger... IE they do not tie directly to the battery. You would have to watch the battery voltage at the screws for the battery flex-cable mount.
- There are lots of notes about the battery voltage being 'high' by peoples viewpoints. If you search around, someone explains the difference in chemistry that the Droid 4 is using and that it does have a higher Vmax during bulk/absorption charge levels. I believe the summary was that it is a non-issue. They aren't trying to 'cheat' the battery into higher voltage for more cap...it's just simply how that chemistry wants to be charged. You'll have to google around to find it.
I am curious to see what sort of 'external' packs I can come up with and likely would limit my charging rate to 1200mA or so just to keep things 'happy'. I got slapped pretty hard over at droidforums by an admin and my post removed for this same info...glad to see the community here is more accepting of my discoveries. :cyclops:
-Also, the other two pins are data lines...not sure if In/out compatible but one is Batt Temp and the other is Communication (for determining battery type). The phone doesn't like having these pins futzed with (can cause reboots/lockups) so there is clearly something on the other end...but sounds like the protection is weak regarding input into the processor/etc.
Once I have my phone near a camera, I will photo my connection method/mods (no direct soldering in-case I have to warranty the phone for other issues). That gave me 6" pigtails of wire that I have hiding behind my cheap-o case right now waiting for proper connections (I exited through the speaker hole on the stock back cover).
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Very excited to see those photos. I can't imagine your post getting removed for that sort of information, that is a shame... Hardware mods are just as much fun as software mods, imho! Plus, they have the added bonus that there is a slight risk of explosion, something I err, enjoy
Brandon314159 said:
- You would have to watch the battery voltage at the screws for the battery flex-cable mount.
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Drat. I really didn't want to peal off the sticker... heh, maybe I could just punch through it with the needle probes and only leave 2 tiny holes .
There are lots of notes about the battery voltage being 'high' by peoples viewpoints. If you search around, someone explains the difference in chemistry that the Droid 4 is using and that it does have a higher Vmax during bulk/absorption charge levels. I believe the summary was that it is a non-issue. They aren't trying to 'cheat' the battery into higher voltage for more cap...it's just simply how that chemistry wants to be charged. You'll have to google around to find it.
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I have done a lot of googling and failed. I'm skeptical that I can't find any "new Li-ion chemistry". The only thing I did find was a pointer to an Anandtech article where the writer said he "heard" they were using a "new Li-ion chemistry" ... with no references or cites. In any event I agree it is mostly a non-issue for most everyone else. I figure they have it all designed for some target duty cycle -- probably about 1 year? maybe 2? Thing is, I plan to keep my phone for 4 or more years like all my past smart phones. The difference this time is that the battery is non-removeable (yes, I know it can be done with tools and some risk). I was hoping to find an app that would interface with the battery management and allow a configurable threshold for the "fully charged" cutoff. With a charging cutoff at about 90% I should be able to triple the life of my battery.
sigh... sorry for the hijack (but there isn't much on the actually battery operation, even around here).
Quick7135 said:
I was hoping to find an app that would interface with the battery management and allow a configurable threshold for the "fully charged" cutoff. With a charging cutoff at about 90% I should be able to triple the life of my battery.
sigh... sorry for the hijack (but there isn't much on the actually battery operation, even around here).
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drain the phone and charge it up in charging mode with the stock charger. this will calibrate your battery so it will charge to 100%
myfishbear said:
drain the phone and charge it up in charging mode with the stock charger. this will calibrate your battery so it will charge to 100%
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He wants to make it so it ONLY takes charges to 90%, to extend the duty cycle of the battery. Honestly, I would just not worry about it, and replace the battery as necessary.
Sent from my Amazon Kindle Fire using xda app-developers app
I put my reply over on this thread that you created, which seems to be more on-topic:
http://forum.xda-developers.com/showthread.php?t=1856514
Cheers!
podspi said:
He wants to make it so it ONLY takes charges to 90%, to extend the duty cycle of the battery. Honestly, I would just not worry about it, and replace the battery as necessary.
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You're probably right but I'm not clear on the risks of damage to the hardware when prying out the non-replaceable battery.
Brandon314159 said:
I put my reply over on this thread that you created, which seems to be more on-topic:
http://forum.xda-developers.com/showthread.php?t=1856514
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Thanks. and I do apologize (again) for the interruption here. It won't happen again.
Quick7135 said:
You're probably right but I'm not clear on the risks of damage to the hardware when prying out the non-replaceable battery.
Thanks. and I do apologize (again) for the interruption here. It won't happen again.
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I'd think you'd be at higher risk of damage playing with the software/firmware interface that controls battery charging than doing an actual battery swap.
It appears to be pretty easy: http://www.ifixit.com/Teardown/Motorola-Droid-4-Teardown/7759/1
No worries on cross posting...just figured better to keep it all over there where there is already a few replies on-topic.
Cheers,
BTW noticed today that the phone says "Charging - Connected to an inductive charging mat" when you connect up power to the back.
I will try to get a shot of the connection when I get home.
My USB port broke... would you think this would charge a completely dead battery.. thank you kindly for your time...
update this will charge a completely dead battery... took an OEM charger cut it open used the red and black... worked perfectly...
why do they call it common sense when only a few people have it...
I've been following the great battery impression thread, which discusses ways to tweak the Nexus 4 settings, ROMs, and so forth for maximum run time between charging. This thread focuses on a different battery concern.
The Nexus 4 lithium polymer battery is sealed, and as far as I know, there are still several unknowns about replacing it. We've seen a tear-down showing how to remove the battery. However, as of now, few users have attempted it and there's not a consensus about how easy or difficult it is to do. Questions include:
Even with the correct tools, are the tabs that secure the Nexus 4's back prone to breakage, potentially leaving the case borked?
Is the battery difficult to extricate from its compartment?
Will it a high quality replacement battery become available inexpensively on eBay and elsewhere, or is it this battery, which was not designed to be user-replaceable, too much of an oddball for that to happen meaning that a replacement battery will be expensive and hard to find?
That said, the ease (or lack thereof) of replacing the Nexus 4's battery isn't what I've come here to discuss.
Given the unknowns about battery replacement, my concern is to how to maximize the Nexus 4 battery charge cycles and reduce the capacity drop of the battery over time. It could be bad if after just a year, the Nexus 4's capacity is already noticeably dropping. Not possible? I'm not so sure. Based on what I've read, it may depend upon how we handle charging.
This article at "Battery University" discusses the discharge characteristics of Lithium batteries, and it is my understanding that Lithium Polymer batteries, like the one in the Nexus 4 mirror these characteristics.
My takeaway from the article is:
Charging the Nexus 4 battery before it drops to less than 50% capacity will greatly increase the number of charge cycles before there's a noticeable capacity drop. Letting the battery nearly completely discharge will greatly reduce the number of charge cycles, and therefore greatly reduce the time before battery replacement will be necessary. (Table 2)
Inductive (wireless) charging, while convenient, generates extra heat that will over time reduce the recoverable capacity of the battery. (Table 3)
Having read this article, I am curious about the charging characteristics of the Nexus 4 and which, if any, charging variables we can control as users to maximize battery longevity.
When I first get a new smartphone I try to do a handful of full cycle charges before doing any partial charges. Your battery is still "new" and in the "break in" period. Many users that were the first to get theirs have reported their battery life as getting better. Of course a lot to do with battery are things like your data usage and what you have syncing.
RealiZms said:
When I first get a new smartphone I try to do a handful of full cycle charges before doing any partial charges. Your battery is still "new" and in the "break in" period. Many users that were the first to get theirs have reported their battery life as getting better. Of course a lot to do with battery are things like your data usage and what you have syncing.
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Click to collapse
Thanks, but I will again clarify that that I created this thread to discuss maximizing the Nexus 4 battery's long-term life and recoverable capacity, not maximizing run-down time in the short-term. That is already being discussed extensively in the great battery impression thread.
I have had a lot of experience with LiIon batteries over the years and I can tell you that the enemy of them is both inactivity and deep discharge use.
Use your phone as you normally would, but avoid frequent deep discharges. Don't be afraid about the number of charge cycles. Frequent charges are better than deep discharge cycles.
These pups have been designed to be used the way most folks use frequently used rechargeable devices. Pop it on the charger when you can, even if you know it won't be there long enough to be topped off. The more frequent and varied activity the better.
I'll add that I do not currently see an LG BL-T5 Nexus 4 replacement battery sold anywhere.
FYI - The Nexus 4 uses an 800 cycle battery as well so makes it even less of a thing to worry about. My SGS2 still gives me good battery life and it's more than 1yr old already, and i think that is a 300 cycle battery. Remember also that at that 800 cycle mark the battery should still have 80% of it's original capacity. 800 cycles is more than 2yrs of constant use/charge every night and for people that don't so much that could put you in the 3yr-4yr range. If you still have this phone 4yrs from now, i think you wont need to complain if it "only" has 80% of it's original charge.
Hi
borntochill said:
I've been following the great battery impression thread, which discusses ways to tweak the Nexus 4 settings, ROMs, and so forth for maximum run time between charging. This thread focuses on a different battery concern.
The Nexus 4 lithium polymer battery is sealed, and as far as I know, there are still several unknowns about replacing it. We've seen a tear-down showing how to remove the battery. However, as of now, few users have attempted it and there's not a consensus about how easy or difficult it is to do. Questions include:
Even with the correct tools, are the tabs that secure the Nexus 4's back prone to breakage, potentially leaving the case borked?
Is the battery difficult to extricate from its compartment?
Will it a high quality replacement battery become available inexpensively on eBay and elsewhere, or is it this battery, which was not designed to be user-replaceable, too much of an oddball for that to happen meaning that a replacement battery will be expensive and hard to find?
That said, the ease (or lack thereof) of replacing the Nexus 4's battery isn't what I've come here to discuss.
Given the unknowns about battery replacement, my concern is to how to maximize the Nexus 4 battery charge cycles and reduce the capacity drop of the battery over time. It could be bad if after just a year, the Nexus 4's capacity is already noticeably dropping. Not possible? I'm not so sure. Based on what I've read, it may depend upon how we handle charging.
This article at "Battery University" discusses the discharge characteristics of Lithium batteries, and it is my understanding that Lithium Polymer batteries, like the one in the Nexus 4 mirror these characteristics.
My takeaway from the article is:
Charging the Nexus 4 battery before it drops to less than 50% capacity will greatly increase the number of charge cycles before there's a noticeable capacity drop. Letting the battery nearly completely discharge will greatly reduce the number of charge cycles, and therefore greatly reduce the time before battery replacement will be necessary. (Table 2)
Inductive (wireless) charging, while convenient, generates extra heat that will over time reduce the recoverable capacity of the battery. (Table 3)
Having read this article, I am curious about the charging characteristics of the Nexus 4 and which, if any, charging variables we can control as users to maximize battery longevity.
Click to expand...
Click to collapse
There is little point in worrying about charging before it's discharged to 50% and/or not charging to maximum. Yes it increases the number of cycles, but is reducing runtime between those cycles, so you have to charge it twice as often using up the extra cycles gained, so overall it tends to even out.
The longevity argument for only partial discharges really only applies at the time of design and specification where the manufacturer can spec a larger battery and sacrifice some of the capacity (by only charging say from 30 to 70%) to get extra charge cycles. Clearly with a mobile phone this isn't desirable to do, as we crave all the the runtime we can get in the smallest form factor possible.
Regards
Phil
shotta35 said:
FYI - The Nexus 4 uses an 800 cycle battery as well so makes it even less of a thing to worry about. My SGS2 still gives me good battery life and it's more than 1yr old already, and i think that is a 300 cycle battery. Remember also that at that 800 cycle mark the battery should still have 80% of it's original capacity. 800 cycles is more than 2yrs of constant use/charge every night and for people that don't so much that could put you in the 3yr-4yr range. If you still have this phone 4yrs from now, i think you wont need to complain if it "only" has 80% of it's original charge.
Click to expand...
Click to collapse
Is the "800 cycle" rating is based on real world usage, or a set of idealized laboratory conditions that few users will actually meet? Many Nexus 4 forum users are reporting running down their batteries to a discharge depth exceeding 90% on a daily basis before recharging. This will dramatically reduce their battery's number of charge cycles. The "800 cycle" rating is only useful if we know the conditions upon which it was tested.
PhilipL said:
Hi
There is little point in worrying about charging before it's discharged to 50% and/or not charging to maximum. Yes it increases the number of cycles, but is reducing runtime between those cycles, so you have to charge it twice as often using up the extra cycles gained, so overall it tends to even out.
The longevity argument for only partial discharges really only applies at the time of design and specification where the manufacturer can spec a larger battery and sacrifice some of the capacity (by only charging say from 30 to 70%) to get extra charge cycles. Clearly with a mobile phone this isn't desirable to do, as we crave all the the runtime we can get in the smallest form factor possible.
Regards
Phil
Click to expand...
Click to collapse
Point taken, although it looks to me like the relationship between discharge depth and maximum number of charge cycles is not linear. From the way I read it, frequent deep discharging can markedly impact battery longevity which is why I'm skeptical of the 800 cycle figure. Given that many Nexus 4 users are currently reporting an inability to make it through a full day without completely draining their battery, those particular users are bound to have shortened battery longevity unless they charge at least twice/day.
Hi
borntochill said:
Point taken, although it looks to me like the relationship between discharge depth and maximum number of charge cycles is not linear. From the way I read it, frequent deep discharging can markedly impact battery longevity which is why I'm skeptical of the 800 cycle figure. Given that many Nexus 4 users are currently reporting an inability to make it through a full day without completely draining their battery, those particular users are bound to have shortened battery longevity unless they charge at least twice/day.
Click to expand...
Click to collapse
Yes it isn't linear, but the advantages are also outweighed by the negatives, such as having to plug it in more often to charge, and if people are struggling to get through the day now on a full charge/discharge cycle.....
The 800 cycle figure is probably about right for chemistry used in the LG Nexus, and most of us will have replaced our phone in a couple of years anyway long before we start to notice the lowered battery life.
The other thing with a lithium batteries is they are like perishable foods, even if we don't use them much, after a few years the capacity has diminished anyway. So even if we only charged the phone twice in two years, the third charge capacity would probably not be that much different to having charged it every day for two years.
So we shouldn't worry about the battery, the best thing we can do is use it as much as possible as it is going to degrade anyway, and we will see little benefit from treating it with kit gloves.
The above also assumes the battery can never be replaced. It certainly is replaceable by the manufacturer or a repair centre, and more than likely most of us could manage a replacement ourselves.
Regards
Phil
One very important thing to realize is that these 500/800 or whatever hundred cycles it's talking about is not how many times it can be charged, period.
It's not like after the 500th or 800th charge, this battery can never be powered on again.
Read the article closely:
" the number of discharge/charge cycles Li-ion can deliver at various DoD levels before the battery capacity drops to 70 percent."
Also, if you lower the voltage of the charge, it seems battery long term life greatly increases:
"Most Li-ions are charged to 4.20V/cell and every reduction of 0.10V/cell is said to double cycle life. For example, a lithium-ion cell charged to 4.20V/cell typically delivers 300–500 cycles. If charged to only 4.10V/cell, the life can be prolonged to 600–1,000 cycles; 4.00V/cell should deliver 1,200–2,000 and 3.90V/cell 2,400–4,000 cycles. Table 4 summarizes these results. The values are estimate and depend on the type of li-ion-ion battery."
Hi
borntochill said:
Is the "800 cycle" rating is based on real world usage, or a set of idealized laboratory conditions that few users will actually meet? Many Nexus 4 forum users are reporting running down their batteries to a discharge depth exceeding 90% on a daily basis before recharging. This will dramatically reduce their battery's number of charge cycles. The "800 cycle" rating is only useful if we know the conditions upon which it was tested.
Click to expand...
Click to collapse
When a lithium battery is fully discharged, it isn't actually completely discharged. LG like other manufacturers will have programmed a level that shows 0% on the phone before it shuts down, but in reality this might still leave 10% or 20% or 2% capacity in reserve, we don't know the figure, but presumably LG have set both full and empty charge points to ensure we see around 800 cycles.
Regards
Phil
---------- Post added at 09:19 PM ---------- Previous post was at 09:10 PM ----------
Hi
ksc6000 said:
Also, if you lower the voltage of the charge, it seems battery long term life greatly increases:
"Most Li-ions are charged to 4.20V/cell and every reduction of 0.10V/cell is said to double cycle life. For example, a lithium-ion cell charged to 4.20V/cell typically delivers 300–500 cycles. If charged to only 4.10V/cell, the life can be prolonged to 600–1,000 cycles; 4.00V/cell should deliver 1,200–2,000 and 3.90V/cell 2,400–4,000 cycles. Table 4 summarizes these results. The values are estimate and depend on the type of li-ion-ion battery."
Click to expand...
Click to collapse
Yes you get more cycles, but because you have a battery with reduced capacity, you are having to charge it more. Overall the benefit isn't as great as the numbers make it. If LG wanted to give us 1600 cycles they could lower the charge voltages, but then the battery capacity would have to be advertised at around 1050mAh, meaning it lasts half the time it does now, and will need charging around twice as often.
For a mobile phone with a typical 2 year life span, the priority is to maximum the time between charges while ensuring the battery lasts the typical 2 years of most peoples phone contracts. It isn't a co-incidence that 800 charges works out as a bit over 2 years if you charge every day.
We don't need to worry about the battery, just enjoy using the phone. Also the battery doesn't just stop working at 800 cycles either, it just doesn't hold as much charge, but capacity is lost anyway over time regardless if you use it or not as lithium batteries start to age the moment they are made.
Regards
Phil
PhilipL said:
For a mobile phone with a typical 2 year life span, the priority is to maximum the time between charges while ensuring the battery lasts the typical 2 years of most peoples phone contracts. It isn't a co-incidence that 800 charges works out as a bit over 2 years if you charge every day.
We don't need to worry about the battery, just enjoy using the phone.
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Click to collapse
A lot of assumptions there, Phil.
My "priorities" and LG's differ. 2 years from now, some will replace their Nexus 4 with whatever shiny new phone comes along that offers holographic video projection chat and does double duty as a sex robot. However, I will happily trudge on with my Nexus 4 for between 3 to 5 years which is how long I typically own a phone before replacement. I don't need bleeding edge, especially if the bleeding edge is a menstruating sex robot phone. Just sayin'.
We don't know if the Nexus 4 battery replacement will turn out to be either very costly and/or difficult. For those of us who don't plan to toss our Nexus 4 into a landfill two years from now, it pays to know what measures we can take to prolong battery longevity.
'Maximizing Nexus 4 battery'
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'Menstruating sex robot'
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Hmmmm....how did that happen...
I don't know if we will really know how good the battery longevity is in this thing until the device is a year old or more. Lithium polymer technology varies a lot. There have been a lot of advances with this tech in the last few years and some companies claim to have developed manufacturing techniques that allow THOUSANDS of charge before noticeable drops in batty capacity. Other technologies developed include the tech Apple uses and advertised in its MacBook line a few years ago that claimed longer battery life and very fast charging compared to Lithium Ion batteries. It all varies. LG claims to have some special tech baked into this battery that allows it to charge to a higher voltage compared to batteries of similar size, but I don't know how long its life is rated at.
666fff said:
'Maximizing Nexus 4 battery'
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'Menstruating sex robot'
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Hmmmm....how did that happen...
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You apparently haven't seen the leaked mock-up of the Nexus 6.
borntochill said:
You apparently haven't seen the leaked mock-up of the Nexus 6.
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I would consider an early upgrade for a menstruating Daryl Hannah any day
Supposedly... The battery on our Google Nexus 6 has a capacity of 3220 mAh.
Specs
BATTERY Non-removable Li-Po 3220 mAh battery
Stand-by Up to 330 h
Talk time Up to 24 h
I purchased a current, voltage, detection tool http://www.amazon.ca/gp/product/B00NNGK4QS?psc=1&redirect=true&ref_=oh_aui_detailpage_o05_s00
made by SainSonic.
Okay, I know this isn't a fluke meter quality and standard, but how come when I charge my phone from i.e. 20% battery capacity left, to reach a full charge the Sainsonic USB tool reports back with a supplied mAH of approximately 1500mah to reach a 100% charge.
Are we to assume the battery capacity supplied by motorola for the Nexus 6 phone to be rigged or false? Is this another one of those cases, where your mileage will vary b.s.
I know the USB detection tool is not a Mil Spec device, but, how can it report back this off of factual value or reading?
Cheers
LormaD
2nd test
OK, so I let the phone on, til the phone did it's own shut down. I even rebooted the phone into Recovery mode, where it eventually powered off, 2x. I know this is bad and not recommended for a battery, but I wanted to try to deplete the battery completely, and using the turbo charger, charge the phone and get a mAH consumption to refill the battery.
From an empty charge to maximum, I recorded 1825mAH. I am unsure, if by TURBO charging the phone, whether I am not registering a true milliamp draw and count. My last test, will take place doing the same thing, but using a standard NON turbo charger to see whether or not this reports a difference or not.
Cheers
That meter does say that it's for between 3 and 7 volts which is pretty much saying it's made for a standard 5V usb spec current. The turbo charger uses voltages of 12, 9 and 5 volts to accomplish its faster charging speed and the charging voltage only goes down to 5V once the battery is almost full somewhere like 75% iirc.
Though it also wouldn't surprise me if the turbo charger doesn't turbo charge when running through that meter. Might check and see if the phone charges any slower when you switch to the normal charger test.
While Charging, the USB meter does show it's outputting voltage as well. AND, while charging I do have the phone using an app like Ampere so I do see that it is in fact indicating TURBO mode. But logically, the phone does complete it's charger in under 2 hours, hence it is charging very quickly = same as turbo charging.
1) It is in fact Turbo Charging. 2) The outputting voltage, even though is variable (from 5 to 9 volts in the case of Turbo Charging) would only relate to varying the mAH per / Sec if you will, from a quicker or slower "Consumption" (i.o.w. if it is quick charging, the rate of supplied mAH is faster than slow charging, so the total amount or capacity of charge is the same, it is just a matter of how quickly can you refill the empty bucket of water, with water).
I am using the Pure Nexus Project Nexus 6 Rom, flashed with the latest Radio, and I am extremely happy and very stable build (so much so, I even sent beans some props and thank$you donation). What I am disappointed with (even with previous roms and build from 5 all the way to 6) is the battery capacity (I loved the Turbo Charging so much, I did away with carrying a battery bank and purchased a 2nd Turbo Charger for the office). I did not purchase the phone new, but did get it in an almost new state (purchased from the typical, "I got to dump this just came out phone and get the latest released phone" type of tech junkie). FWIW, it is the 64gb model, and about 6 months old (I have the google bill showing the manufacturing date and sell date). I can't say I am impressed with the overall battery capacity of this phone, but it is designed to get me through a day 90% of the time, so I am never really worry free, it simply not a tank like some other monster phones that I have had (I like smartphones with a minimum of 6" of screen, my previous phone was the Samsung Galaxy Mega 6.3).
I will be honest, I have always been a battery junkie from my days as a Radiocomm R&D department tech, so I have a carryover Battery Analyzer (5K $ piece of bench equipment) that I can use for most of my battery related equipment (from battery powered yard tools, commercial grade walky talkies to household products like cordless home phones). But things like cellphones would not work, because I do not have the correct adaptor that has the correct resistance type, delta voltages, and connect-ability. In most cases if I jerry rig something (like I was curious to know what the capacity of an Energizer D size battery was compared to a Duracel D size Alkaline Battery capacity was, I could read the output mAH capacity from either battery and know which does really last longer) I can get the output capacity but cannot perform a 3x count battery analysis (which basically performs a full charge discharge 3 times in a row and spits out the 3 capacities back) which in fact I would NOT do on a Lithium battery for obvious reasons.