yashsingh1/xdaforums huggingface dataset:
[EVO 4G General] v01rider:
agreed. to cause overcharging, you have to get above the voltage. if you do not use your phone when charging, you will not get above that voltage. even so, imho, ive used my phone plenty of times while charging, including calls, and the battery never ever got close to being 100*f.
[EVO 4G General] mlin:
Gotcha, so the problem could be with the voltage sensor?

Also, OP, as an EE do you have access to a multimeter?
[EVO 4G General] bkrodgers:
No, the concern is also about continuously charging a battery above 4.05V. This behavior is exactly what SBC does -- there's no debate about that. I think the debate is about whether that risk is significant, or the outcome could be dangerous.
[EVO 4G General] v01rider:
http://batteryuniversity.com/learn/article/lithium_ion_safety_concerns

http://batteryuniversity.com/learn/article/the_high_power_lithium_ion

http://batteryuniversity.com/learn/article/discharging_at_high_and_low_temperatures

this phone while charging will never reach 482*f unless charged in a car sitting in phoenix, az with the windows rolled up in the sun all afternoon.

a sample of my charging via laptop in a 75*f room. i honestly think to reach an "unstable" state, you have to be a moron to catch it on fire.

2011/01/13|17:10:44|34mA|100%|4213mV|87.2ºF

2011/01/13|17:11:44|34mA|100%|4213mV|87.2ºF

2011/01/13|17:12:44|34mA|100%|4215mV|87.6ºF

2011/01/13|17:13:44|30mA|100%|4213mV|87.6ºF

2011/01/13|17:14:44|22mA|100%|4211mV|87.6ºF

2011/01/13|17:15:44|14mA|100%|4210mV|88.7ºF

2011/01/13|17:16:44|34mA|100%|4214mV|89.7ºF

2011/01/13|17:17:44|28mA|100%|4213mV|89.2ºF

2011/01/13|17:18:44|24mA|100%|4212mV|88.7ºF

2011/01/13|17:19:44|28mA|100%|4212mV|89.7ºF

2011/01/13|17:20:44|28mA|100%|4218mV|89.7ºF

2011/01/13|17:21:44|16mA|100%|4223mV|89.2ºF

2011/01/13|17:22:44|26mA|100%|4215mV|89.2ºF

2011/01/13|17:23:44|24mA|100%|4213mV|89.2ºF

2011/01/13|17:24:44|20mA|100%|4217mV|89.7ºF

2011/01/13|17:25:44|20mA|100%|4213mV|89.2ºF

2011/01/13|17:26:44|18mA|100%|4213mV|89.2ºF

2011/01/13|17:27:44|18mA|100%|4218mV|88.7ºF

2011/01/13|17:28:44|16mA|100%|4213mV|88.7ºF

2011/01/13|17:29:44|16mA|100%|4220mV|88.1ºF

2011/01/13|17:30:44|14mA|100%|4213mV|88.1ºF

2011/01/13|17:31:44|16mA|100%|4215mV|88.1ºF

2011/01/13|17:32:44|16mA|100%|4214mV|88.7ºF

2011/01/13|17:33:44|4mA|100%|4211mV|88.7ºF

2011/01/13|17:34:44|14mA|100%|4214mV|89.7ºF

2011/01/13|17:35:44|16mA|100%|4215mV|90.3ºF

2011/01/13|17:36:44|12mA|100%|4217mV|89.7ºF

2011/01/13|17:37:45|6mA|100%|4218mV|89.7ºF

2011/01/13|17:38:44|-8mA|100%|4213mV|89.7ºF

2011/01/13|17:39:44|12mA|100%|4224mV|90.8ºF

2011/01/13|17:40:44|6mA|100%|4212mV|91.4ºF

2011/01/13|17:41:44|12mA|100%|4210mV|91.4ºF

2011/01/13|17:42:44|10mA|100%|4211mV|90.3ºF

2011/01/13|17:43:44|10mA|100%|4209mV|89.7ºF

2011/01/13|17:44:44|8mA|100%|4210mV|89.7ºF

2011/01/13|17:45:44|10mA|100%|4211mV|90.8ºF

2011/01/13|17:46:44|8mA|100%|4210mV|90.8ºF

2011/01/13|17:47:44|8mA|100%|4210mV|90.3ºF

2011/01/13|17:48:44|6mA|100%|4210mV|89.7ºF

2011/01/13|17:49:44|6mA|100%|4210mV|89.7ºF

2011/01/13|17:50:44|6mA|100%|4213mV|89.2ºF

2011/01/13|17:51:44|4mA|100%|4213mV|89.2ºF

2011/01/13|17:52:44|4mA|100%|4213mV|88.7ºF

2011/01/13|17:53:44|2mA|100%|4214mV|88.7ºF

2011/01/13|17:54:44|2mA|100%|4214mV|88.7ºF

2011/01/13|17:55:44|2mA|100%|4213mV|88.7ºF

2011/01/13|17:56:44|4mA|100%|4213mV|89.7ºF

http://cdn1.knowyourmeme.com/i/23641/original/182250_boobs_n_1.jpg
[EVO 4G General] xlGmanlx:
It couldn't get hotter than Slim shady

hotter then a set of twin babies

In a Mercedes Benz wit the windows up

And the temp goes up to the mid 80's
[EVO 4G General] scooter185:
The issue isn't the battery overheating from the charge, it's from the voltage corroding the battery and causing instability which could lead to venting. In this case temperature would be a symptom of failure, not the cause.
[EVO 4G General] v01rider:
:D hahahaaha right!!!
[EVO 4G General] v01rider:
so lower the volts in the sbc so it dont reach max
[EVO 4G General] wuclan48:
I hope for your sake that this statement doesn't prove to be as ironic as I'm finding it. You understand that it's not failure caused by increased temperatures that people are worried about, right? One of your quoted items even proves the concern others are having, "The time at which the battery stays at 4.20/cell should be as short as possible".
[EVO 4G General] wuclan48:
aka use a stock charging kernel...
[EVO 4G General] v01rider:
what difference does it make if you are overclocking and reaching 4.2v or charging and reaching 4.2v? why has no one ever *****ed so much about overclocking and screwing up batteries?
[EVO 4G General] mlin:
I'm confused. According to battery monitoring programs all of the kernals I use charge above 4.05V. I thought the issue was with going above 4.2V...

Tapa tapa tapa
[EVO 4G General] wuclan48:
Facepalm.jpg

Sent from the void...
[EVO 4G General] xlGmanlx:
interesting article

http://www.androidpolice.com/2011/01/13/makes-sense-htc-evo-4g-batteries-have-overcharge-protection-chip-inside/
[EVO 4G General] v01rider:
thank you. i just saw this myself. and there is even a thread here on xda about it

http://xdaforums.com/showthread.php?t=906144
[EVO 4G General] pardonmyownage:
It's the fact that it's staying at any voltage above 4V and having current actually still being put in constantly. That will cause the corrosion
[EVO 4G General] mlin:
So then SBC isn't anymore "dangerous" than any other kernal that charges above 4.0 V?
[EVO 4G General] gx1400:
....

our batteries aren't manganese.

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

Note: Source [xda-developers] at end of article.

Would you really trust androidpolice.com to be your source on electronics safety and Li-Ion chemistry/physics.

/intelligence
[EVO 4G General] xlGmanlx:
probably not, but apparently we are trusting XDA members with ours "EE thread"? not sure i follow the logic
[EVO 4G General] bkrodgers:
It can go above 4.05, but once it hits 4.2, you're supposed to cut off the charging and let it drop back down below 4.05 before you charge it again. The oft quotes battery university article says:

"A continuous trickle charge above 4.05V/cell would causes plating of metallic lithium that could lead to instabilities and compromise safety."
[EVO 4G General] mlin:
Ok. So then theoretically, if I were able to remove my phone from the charger as soon as it hits 4.2 V, then I should not see the rapid drop to 90%?
[EVO 4G General] gx1400:
Yes and you can see this with the stock kernel

Sent from my HTC Evo
[EVO 4G General] mlin:
I've tried unplugging the phone as soon as the light is green and I still get the quick drop... Maybe the light turning green does not indicate 4.2 V.
[EVO 4G General] v01rider:
a side note gx.....

it appears that you dont like anyone on this forum that wants to contribute, test, or help out others.
[EVO 4G General] mlin:
Either that or he just doesn't have any class...
[EVO 4G General] v01rider:
agreed. its the internet and all, but wow. how immature can one be? put that in the original post about that rom, ok, i might could see. but, put it in your sig for everyone to see in any thread posted in. :rolleyes: reeeealll classy :rolleyes:
[EVO 4G General] Hemidroids:
I work DIRECTLY with MANY EE's and not to knock you but they are no more qualified then the cook at dennys when it comes to practical application. I build the crap that they design. Needless to say I ALWAYS have to fix their ****ups.
[EVO 4G General] pardonmyownage:
Theoretically yea. I'm not saying the HTC charge method is perfect.
[EVO 4G General] evohack99:
Wow my eyes hurt after two hours of reading this stuff, I flashed the new burnt droid worth out sbc, didn't know what it was, needless to say I do now.

Can we still obtain this kernel for our own "experimental use"

I have vast knowledge with li po batteries which are the like of li ion batteries. I understand what it can do, I race r/c monster trucks at 60 plus mph we damage li po batteries. And these EE'S KNOW what they are talking about, go to "youtube" and watch some li po battery explosions. This is somthing that should be delt great risk. But no one should be held responsible but yourself for any damage done.

QUESTION to the ee's: I was usin wireless tether for three laptops, and charging my phone at the same time,my phone got to the point that the metal kick stand could be hot enough to burn me, is this due to using so much battery so quickly and charging at the same time? Could that have damaged my battery?
[EVO 4G General] xHausx:
Do the hundreds of web sites that say the same thing as every one else here not mean anything to you?

I invite you to critique my post in the thread below and am curious as to your opinion about it. People have repeatedly responded to your posts that you think support your argument that they are safe however I have never seen you even acknowledged anything that goes against what you want to believe.

I have the code for both the stock kernel and the sbc modded ones handy if you would like to review it and if you want to post a log of your battery charging with the mod I'll even show you exactly where and how much it is being overcharged.

http://xdaforums.com/showpost.php?p=10588701&postcount=222
[EVO 4G General] mattykinsx:
http://batteryuniversity.com/learn/article/charging_lithium_ion_batteries
[EVO 4G General] gx1400:
I have my own reasons for disliking AndroidBall, if you would like to hear them before attempting to slander me, feel free to PM. Until a moderator requests I change my signature it will remain as long as I like.

Until then, please restrict your comments to the discussion of the forum.
[EVO 4G General] raiderinks:
Of course, although not a very good one. One of my friends has an oscilloscope and 3 rail supply in his place.
[EVO 4G General] gx1400:
Whether you 'trust' the members or not, some of us posting in this thread are degreed Electrical Engineers and we are sharing our concerns and knowledge. We are not experts on computer or embedded programming like some of the devs, but I believe we have a better understanding of the physics regarding these batteries than the kernel developers are. Also some of us (I do) feel an obligation to share a warning to the uninformed masses.

The thing that pisses me off is people saying 'look at my results, obviously its safe because my battery isn't going above 4.2V and its not getting hot'. That's not the entire concern and those observations are short term only, I understand that I could be wrong , but I believe the long term effects could be detrimental to the integrity of the battery.
[EVO 4G General] gx1400:
I understand your concern about inaccurate measurements, but I don't believe that is the issue with the harm to the battery's integrity.
[EVO 4G General] raiderinks:
Thanks, but arguing the merits of the stereotypical designer/prototyper relationship isn't going to accomplish a single thing.
[EVO 4G General] mattykinsx:
Plus, isn't what is being claimed here pretty much backed up by the links and data being presented?

I mean, that's what it seems like to me.

Dismissing data because you don't like what it says...doesn't work.
[EVO 4G General] u921333:
Ok I let my battery charge overnight on SBC v7 with stock HTC battery pulled it off and checked with a multimeter granted only a 30 dollar or so one from Sears LOL and pulled back 4.178 volts the battery widget read 4.207 so im assuming the small drop was from removing from charger. Can some other people post their results so we can at least get the "overcharge" part cleared up.

I am very interested in if we have a few people that gets a high results from the test. I am on HW version 002 just in case there was any changes based on HW versions as well.
[EVO 4G General] raiderinks:
This is a great start. I would recommend we get the following data from everyone doing this test:

HW Version

Kernel Version

ROM

Voltage using "Battery Monitor Widget" last report before removing battery

Immediately remove battery and measure the voltage across the two outside pins. The battery should not be plugged into anything other than your digital multimeter.

For the sake of control, list the manufacturer and model number of your DMM.
[EVO 4G General] gx1400:
Removing the battery from the phone completely changes the load on the battery and will effect it's voltage. You would have to measure it in place to compare readings.

Again let me reiterate. I don't think its the fact that the battery is at 4.2 volts that is the concern it is that the SBC kernel HOLDs the battery at 4.2V. From what I understand about Li+ and is confirmed by articles, holding a battery at that voltage can be harmful.
[EVO 4G General] raiderinks:
Oh, I am in agreement with you, but if people want to contribute some data, having open circuit voltages might be useful.
[EVO 4G General] u921333:
I agree I think that Holding it at 4.2 is one concern but I think about every 10 post the worry of overcharge keeps coming into the discussion. At very least testing this will eliminate that part or if we get say 10 people that some how end up with a reading of say 4.32 volts some how then its a huge red flag and could point to why some had battery failures.

Again just trying to eliminate some of the easiest items from the equation and leaving the more complicated keeping battery at a constant 4.2 volt level and plating to the EE bunch ;).
[EVO 4G General] exploited789:
Hai Guise,

Ill just leave this here.

http://xdaforums.com/showthread.php?t=906144
[EVO 4G General] mattykinsx:
This has been posted in here before.

Although it only addresses ONE issue that has been discussed here, it doesn't address the other.

Also, there is NO evidence that the chip is what it has been suggested.

http://xdaforums.com/showpost.php?p=10540483&postcount=56

http://xdaforums.com/showpost.php?p=10597028&postcount=57
[EVO 4G General] mattykinsx:
http://xdaforums.com/showthread.php?t=913401

This post is about the protection circuit.
[EVO 4G General] v01rider:
thank you for changing your sig.

Originally Posted by v01rider

a side note gx.....

it appears that you dont like anyone on this forum that wants to contribute, test, or help out others.

Originally Posted by mlin

Either that or he just doesn't have any class...

I have my own reasons for disliking AndroidBall, if you would like to hear them before attempting to slander me, feel free to PM. Until a moderator requests I change my signature it will remain as long as I like.

Until then, please restrict your comments to the discussion of the forum.

__________________

Sprint HTC Evo - CM6

Basics of ADB here

All Cellular and Wimax Radios
[EVO 4G General] v01rider:
granted its wiki, but ive read this similar statement on other sites

http://en.wikipedia.org/wiki/Lithium-ion_battery
[EVO 4G General] mlin:
Would leaving an evo charging indefinitely running an SBC kernel (i.e. constantly maintained around 4.2 V) be a reasonable method to find out the real world dangers of this charging method if any?

Also, is it confirmed that maintaining the battery at 4.2V does in fact increase the likelihood that the battery will fail in a catastrophic manner?

Tapa tapa tapa
[EVO 4G General] pardonmyownage:
exactly... battery monitor widget wouldn't be wrong by that much to make a difference. its the fact its holding at the voltage while a constant load is being put into it. pulling the battery and measuring the voltage wont tell us anything that would be helpful.
[EVO 4G General] mattykinsx:
I don't know the answer to the first question but...

http://xdaforums.com/showpost.php?p=10595409&postcount=329
[EVO 4G General] mlin:
Thanks for the link, good read at battery university. However, after reading both that and this http://electronics.howstuffworks.com/lithium-ion-battery1.htm I am quite convinced that this kernel poses no danger. Furthermore, it seems that heat is a concerning factor as well as an indicator of failure. I think I'll go back to SBC and stop using it if I notice a rise in the battery temperature. Can someone tell me a good program that will log voltage and temperature of the battery?

Tapa tapa tapa
[EVO 4G General] m20120:
Battery Monitor Widget (in the Market) by 3c06 will do the job.
[EVO 4G General] gx1400:
this is purely conjecture, but I *BELIEVE* that the SBC won't likely cause catastrophic failure, like venting, but I believe it can potentially just degrade lifespan dramatically. Again purely conjecture, I can't comment on what the quality of battery has been that SBC has been seeing with venting, but its a possibility.
[EVO 4G General] xlGmanlx:
OP check your PM's
[EVO 4G General] evohack99:
I have an idea, DEVS! Make it "hold a charge at 4.1v instead of 4.2v then it won't harm the battery? Yes? No?

Sent from my netarchy_toast, froyo beast of a machine evo!
[EVO 4G General] xlGmanlx:
i think one of the main questions the OP aims to answer is what the damage is or to what extend does that impact the battery. In my opinion we haven't been able to determine what the impact of "full charge" does to the battery at least not that i have seen and this is one of the issues they plan on tackling, so 4.2 might be good, or it might not be, heck for all we know 4.05 could be bad etc....
[EVO 4G General] xHausx:
Anyone have a current widget log showing a sbc kernel charging the battery until the current reaches zero?
[EVO 4G General] xlGmanlx:
i do, has a bunch of 2's and some 0's in it, you want me to post?
[EVO 4G General] xHausx:
4.1V would probably help some but his bump charging idea would be the closest to what HTC uses and most likely the safest. Although it would still introduce more stress on the battery then stock it would be no where near as bad as the current kernels are.
[EVO 4G General] xHausx:
Does it show it charge the battery up from below 70%?
[EVO 4G General] mlin:
Not to be picky, but bad here is completely subjective as there is no proof of any negative consequences besides decreased battery life at this point.
[EVO 4G General] mattykinsx:
Forgive me but we do know that holding a battery at a full charge will eventually have bad consequences. [well, that is, unless on xda we choose to ignore university's and other science related site's take on it, which really wouldn't surprise me]

The idea that because people, whom have only been using the kernel for a month or less because it has only been out about a month, haven't had an issue yet therefore it's safe is nothing more than silly.

If I smoke cigarettes for a month and don't get cancer, it doesn't mean I'll never get cancer.

I'm not going to try to suggest that it is a fact that these kernels will cause issues, or issues that even matter [if it so comes that it will cause the battery to fail after four years of use then the issue is moot at best], but to completely dismiss it is wrong...especially with the understandings that we DO have about batteries.

I'm not targeting you on this, just a general comment.

You are right though, we all need to be careful about our lingo because we just don't know 100% either way.
[EVO 4G General] mlin:
Look, working in basic science research has trained me to be skeptical. So far I have not seen any definitive evidence stating anything concrete and statements like "may lead to instability" or "bad consequences" mean nothing to me. I would like to see peer reviewed journals or somehting that holds similar weight with definitive results before we brand SBC as unsafe and say its the cause of batteries exploding/venting/and catching fire when these such things have been happening for years prior to such kernels. I'm not saying the possibility isn't there, just that the evidence thus far supporting the claim is not very strong.

As far as your smoking analogy goes- it would be relevant if the evidence were there regarding these batteries, charging, and kernels. Then it would be silly to deny it, just as its silly to deny cigarettes contain dozens of carcinogens and lead to cancer and heart disease (but not in everybody).
[EVO 4G General] xlGmanlx:
yeah, is there a way to export it without having to take about 50 screen shots?
[EVO 4G General] bwcorvus:
I'm gonna help you guys out, I just plugged in my backup evo with a stock battery, its currently at 85%, I will leave it plugged up for 24 hours and send you the log. Its set to update every minute.
[EVO 4G General] xHausx:
Peer reviewed articles about a custom android kernel? lol

There are plenty of technical documents out there that say not to do this, you are just looking for excuses to discount them.
[EVO 4G General] ccossin:
Is this what you need, Haus?

This has been a telepathic transmission from the Outer Limits.
[EVO 4G General] xHausx:
can you attach the actual log file for me? Can't do much with a picture :)
[EVO 4G General] mlin:
Not articles about the kernels, but rather Li ion batteries. I'm not looking for reasons to discount anything, I am open to the idea that this may be dangerous, I would just like to see more evidence correlating sustained voltage above 4.05 V and an increased rate of catastrophic failure. Don't be a douche bag and tell me I'm just looking for reasons to blah blah blah. I know what I'm doing, and I'm not looking for excuses, I'm asking for better data. So, if there are so many technical documents that show what I am asking for, please link me to some of them and I will gladly read them and willingly change my stance if they provide "real" information, not the vague language we have encountered thus far.
[EVO 4G General] mattykinsx:
http://xdaforums.com/showpost.php?p=10595409&postcount=329
[EVO 4G General] ccossin:
Tapatalk will only allow me to attach pics. Will the web interface allow txt file attachments?

This has been a telepathic transmission from the Outer Limits.
[EVO 4G General] xHausx:
Sorry man, that was just too easy though. lol

We're going in circles, this has all been covered before. Can you honestly say the people who were referenced in those posts are not trustworthy on this subject and that a hobbyist kernel dev is more reliable then them?

http://xdaforums.com/showpost.php?p=10488764&postcount=194

yup, as long as it has a .txt or .docx extension on it.
[EVO 4G General] mlin:
Sorry man, I'm not trying to be a pest or play devil's advocate. I guess I am just more of a numbers and statistics person and want to see the data behind statements such as this: "A continuous trickle charge above 4.05V/cell would causes plating of metallic lithium that

could

lead to instabilities and compromise safety," which I keep getting links to but its not what I am looking for.

I am now at my computer and perhaps can research this a little better than what I accomplished while mobile.

As of right now I am not convinced these kernels pose any real world danger, though neither am I convinced that they don't. The battery life gain from SBC was so phenomenal, though I have since given SBC up until more concrete information is presented either way.
[EVO 4G General] xHausx:
One thing to realize is that Nothing is certain in physics. You will never hear a physicist say something is 100% for sure unless they are lying. They say it in fact Does cause plating but they don't specify it will fail because that depends on too many variables. Time, condition of the battery, quality of the battery, heat, etc. If it is only above that voltage for a short time each cycle the battery may be worn out before the plating causes it to become instable.
[EVO 4G General] scooter185:
I don't believe anyone has pointed it out yet in this thread, but everyone seems to have demonized all sbc kernels, but v8 charges differently than v7. using bump charging compared to trickle charging.

In the omg my battery started smoking thread, someone brought this up, but I think it got buried in with all the other crap. IMO it's a shame to see it become a casualty of all this despite the fact it charges differently.
[EVO 4G General] mattykinsx:
That is important information and should be reviewed too, if true.

Let's keep in mind that the only reason those kernels have been taken down was ms's own choice.

And the only request has been for a warning to be placed in the OP, along with further testing.

The only reason for the "casualty" was the dev's choice.