- 06-30-2010, 03:09 PM #51
What charger unit are you using
I am reposting this from another battery thread to test a theory about potential problems with the HTC Evo charger. please read on and contribute your experience with battery life and charger unit used. Let see if there is a pattern here that may narrow down the culprit and gets us closer to a solution for all.
I have read multiple threads about Evo battery problems on this and other boards and I found one talking about problems with the HTC charger failing to fully charge the battery; many indicating the charger stopping the charge before reaching 100% battery. This prompted me to look up a bit further into charging circuit design flaws and made me wonder if the external HTC charging unit may be also to blame on this issue.
This is why I post this question.
First, I have never used the OEM HTC Evo charger that came with the phone. The reason, I have four Palm OEM chargers from other phones that fit the Evo and provide excellent charge output. Other than my battery dropping to the mid to low 90's minutes after unplugging in the morning, I have never experienced any problems with battery life. Even if I fail to connect my Evo a second time to "top-off" my battery in the morning, I always make it through the day with plenty of battery power to spare. In fact, as unbelievable as it may sound to some, I don't recall ever getting home after work with less than 50-60% left on my battery.
Second, after reading through many similar threads here and elsewhere, it seemed that most people complaining of either poor battery life and/or grossly imcomplete battery charging, reported using the HTC Evo OEM wall charger unit. Most others that didn't have problems, reported using third party chargers such as myself.
So a pattern seemed to emerge from all those posts in my mind. Could it be that in addition to the way the internal Evo charge circuitry seems to works, some or all of the HTC OEM charger units may be suffering from poor engineering/manufacturing flaws, therefore adding to the deficient charge and as consequence, poor battery life? If this theory has some validity, then a substantial improvement in battery life for those affected may be achieved by using a good quality third party wall charger.
To test this, I post the following questions to you all:
1. How do you rate your battery life?
2. What wall charger do you use?
a. HTC Evo OEM
b. another brand OEM
c. generic third party
I'll go first:
2. Palm Pre OEM
- 06-30-2010, 03:44 PM #52
- 06-30-2010, 04:17 PM #53
I'm at 49% after after 7hrs of light txting, 1 phone call, and 30 minutes of watching futurama. Most days involve heavy pandora/streaming radio usage and yesterday I got only 6 hrs streaming slacker radio for an hour and iheart radio for 3 hrs.
2. HTC Evo OEM
- 06-30-2010, 04:32 PM #54
Im interested to see where this goes on the charger thing.
I think the charger takes a little long sometimes too.
I seem to notice the times I get a better life out of it is when i do the green while turned on, then turn off to go green, then turn back on to green.
Goes green in all states after the charge fairly quickly, but i noticed the times i do this, i get +20hrs
- 06-30-2010, 04:50 PM #55
- 07-01-2010, 04:06 AM #56
The thing with Lithium Ion Batteries... You Can't fast charge em
The thing about "Smartphones" is that they really are pretty dumb still in how they display battery charge levels.
The fast ramp up to 4.2 volts from the stock 1 amp charger really is misleading when the phone says fully charged. Lithium Ion Batteries (& Every other Rechargeable Battery I've built charging circuits for) need a duration of "Bulk" charge at the specified fully Charged Voltage. Lead Acid Batteries will be undercharged if you fast charge em to 14.4 volts with a lot of current & disconnect the charger. The same is true for Lithium Ion & even more so due to the higher internal resistance of Lithium Ion. When you try to fast charge a Lithium Ion, a lot of the Extra power you are pushing to the battery is wasted as heat from the internal resistance, Lead acid batteries (Especially AGM) have a lower internal resistance which allows more of the power you are forcing into the battery to be used for actual recharging which is why you can fast charge them to around 95% without a bulk charge at full charging voltage & high amperage. When you fast charge to 4.2 volts required by 3.6V lithium Ion batt packs, you are only charging to around 70% of maximum capacity & they need an even LONGER bulk charge at 4.2 volts to reach 100% charge. This makes the FULL 100% charging times between high amperage chargers & low Amperage chargers on Lithium Ion about the same because the low amp charger will take longer to reach 4.2 volts but needs a shorter bulk charge, while a high amp charger will reach 4.2 volts quickly, but need a longer bulk charge to reach 100%. If I remember right for Lithium Ion ONLY, reaching 4.2 volts on a slow low amp charger will yield about 85% full capacity while a fast high amp charge will reach 4.2 volts at around 70% of max charge (Google it & let me know if I'm wrong)
I've never used the included wall charger, but it seams to me that the Evo Does in fact trickle charge the Bulk charge when left on a USB connection overnight. It will say 100% charged fairly quick, but it still continues to trickle charge the battery at 4.2 volts even after it says full charge WHICH IT SHOULD DO. My first two days of using the EVO had me really worried about battery life, but everynight I connect it to my constant on USB connection on my computer & after a moderate day of work usage (10 to 12 hours of constant push corporate email @ 3 per hour, Gmail @ 5 per hour, Facebook 1 per hour, Web Browsing 2 per hour, Weather checking 3 per shift, phonecalls 4 per shift, video 2 per shift, & pics @ 20 to 30 per shift) I still sit at around 75 to 80% charge at the end of the day going home most times.
The biggest thing to give me more battery life I've noticed is disabling Google Talk auto signin, Stopping the HTC weather, news, & stock autoupdates. When I wanna check these, I update manually.
Seams data usage on the phone is the biggest sucker of power. My Cell Standby is always around 43% due to being in a shielded pole barn with tons of EMI & RFI emitting devices (Laboratory) inside of a warehouse on the outskirts of the city.
Also I do notice a longer battery life throughout the day when i keep the phone attached to the USB connection overnight. If it is fully charged & I unhook it that night, I wake up to around 85 to 90% charge after 8 or 9 hours of sleep.
Maybe if I have time I'll hook up some real equipment & data log the current consumption for the Evo while charging over a few hours and see what it is really doing. I know HTC would have to design the charging circuit around 500mA of current from a USB connection, But I'm wondering if it is smart where it boosts the current capability when it senses that a wall charger is connected & not a USB. Also what happens when it is charging & there is a full heacvy load on the phone? Does it disconnect the charger if the current draw reaches a certain draw in order to stay within UL specs?
- 07-01-2010, 04:58 PM #57
- 28 Posts
In reference to the recommendation to use ATK - I use ATK and kill everything except gmail, clock, facebook, and weather.
- 07-01-2010, 05:23 PM #58
- 07-02-2010, 10:49 PM #59
2. HTC OEM
This is my first 'day' with the phone, rev3 and with the OTA update currently at 9hr 52min and 27% battery. I have everything set to 'once a day' for syncing except GMAIL and only have WIFI enabled.
I made one 45min call, listened to 30min of music, been using Meebo heavily, texting, about 33% of my time using Dolphin HD browser and/or manually updating Friendstream with only 3hrs of that time 'idle'.
So far way better than the reported 4-5hrs before recharging claims but nowhere near the 16-20hrs as some users report. I'd love to know what I'm doing wrong!
- 07-02-2010, 11:12 PM #60
Re: New EVO Battery Life Sticky: Please Contribute
- 07-03-2010, 01:56 AM #61
- 07-03-2010, 11:35 AM #62
I am confused about something.
I turned the sync off on the power widget and I am still getting emails. I thought I read on here that if you turn that off you would not get data but phone calls and gets only. I really don't need the apps to sync all the time and the weather, Facebook and other apps I can just start them myself and update. I wonder if this will get me more battery life.
Anyone else done it and got some results?
- 07-03-2010, 12:30 PM #63
- 602 Posts
OK so to any and everyone still getting bad battery life try this. When you are not using the data network(WiFi, Weather, Internet) basically when the phone is in your pocket/purse. - Hold the power button as if you were going to turn the phone off and toggle Mobile Network off. Turn it back on if you need the net and then right back off... and yes with this off you can still place calls and send receive sms texts (not mms)
Doing this I, after 12 hours off the charger and a bad signal for the most part; am at 80%
so to recap - (Hold) Power Button>Mobile Network off
- 07-03-2010, 02:39 PM #64
I've been fighting the battery thing for a week or so now. For the first 2 weeks I had it the battery was very good. My usage was a lot less during that time so I thought that would explain the issue I have had the last 2 weeks. I was getting about 5 to 7 hours at a time with pretty steady usage. I loaded Juice Plotter to watch and see how much actual time I had. After a full charge it told me 5-6 hours of time left. Even after I removed all widgets and turned off all unnecessary syncing. I tried all of the scenarios to get a full charge and every time I still only got a 5 -6 hour battery life and it really only lasted that long.
Fed up I did a factory reset and will see how that changes my power use. I have changed the settings for syncing and have no widgets. I am by no means a phone novice and I love the EVO and will do what it takes to fix it.
Now today, the first day after the reset Juice Plotter says I have 10 plus hours remaining and its actually been going up. Hmmm.
Well, I guess we will see. The only thing i did was this from another board.
Also need to calibrate the battery...
With the phone in the on position.
Fully charge the battery with the phone on... (until the led turns green.)
Once the led turns green, unplug the charger until the led goes off.
After the led goes off, plug the charger back in. When the led turns green , power off the phone.
now.... with the phone fully powered off...
1. Unplug the charger.
2. Wait until led goes off.
3. Plug charger back in until the led turns green. When it turns green, unplug the charger again and go to step 1.
4. repeat steps 1 and 3, 10 times. This may take anywhere from 30 seconds to 30 mins per cycle. Typically only about 1 minute. though.
- 07-03-2010, 06:31 PM #65
- 68 Posts
But here's my question... Should such a calibration only be done once, or should it be done as often as possible? If so (or if not), why? What is the rationale/science behind the answer? I have the time and energy to calibrate often, if it will really help. It has definitely helped after just one calibration. I'm just wondering if it will actually help to keep doing the "plug/unplug" stuff.
Anybody know? Thanks...
- 07-03-2010, 08:13 PM #66
- 07-03-2010, 11:20 PM #67
- 21 Posts
I'm currently at 40 minutes in Standby with 100% battery.
Before, within a few minutes, the battery level drops to 90-95%.
The weird thing was the led took a minute before it turned green, when the phone was off. It should have taken a few seconds, if it was truly charged at 100%.
My question is do we need to repeat these steps again? Or is it a one time thing?
- 07-04-2010, 12:53 PM #68
- 62 Posts
Right now I get about 12-16 hours depending on video/music but always with moderate to heavy web use. I dont try to get beyond that because I have to set the alarm clock and sleep.
Heavy use like gps with nav/roaming and it drops to like 6-8 hours. The battery life seems to have improved over time or I've managed to take my hands off of it more.
I think part of the reason the battery is lasting so long is because I completely drain it a couple times each week. I charge it while I sleep so I cant tell you how long that takes.
Also, the first few times I charged then completely drained it to the point of shutting down. That was with the supplied power adapter and cable. The battery got HOT while charging with that but almost too hot to handle with a USB auto adapter. I got less use time from that auto adapter too btw.
My dog chewed the original cable so I used the cable/adapter from the free bb bluetooth headset and it was a very slow charge that time but a cool charge and it lasted a long time iirc. Now I have a belkin cable and charge it from my pc, never gets hot at all that way.
I dont use a task killer anymore. If I have opened a ton of apps I may restart when I am done using it for a long time.
I ditched all the pretty widgets and use launcher pro with my apps as buttons instead. Only gmail is set to sync and wifi & bluetooth are off most of the time. It may search a bit more than normal for signal when I am at work because of the thick concrete walls.
I have a LIVE (gasp) wallpaper too (anipet aquarium).
- 07-04-2010, 01:29 PM #69
Is the phone really that bad if you don't mess with the settings? Every review states how horrible the battery life is and they only get 4hrs max on a full charge but even before I tweaked it I was getting 6-7hrs.
- 07-04-2010, 10:00 PM #70
- 07-05-2010, 12:33 AM #71
- 6 Posts
Preformed a test this weekend as I was not leaving the house. So I fully charged my EVO and then only spot checked it over the weekend for email and misc stuff. My EVO is rooted with EVOBEASTV02 and RMBLOATV02 for Sprint bloat ware. As well running Advanced Task killer in auto, Excluding: Titanium Backup, Several mail accounts, Facebook. As well have live wall paper running.
Normal day use I get about 20 Hours without an issue but at this point Im at 43 hours and still have 68% battery life.
Did not preform the new update either. My first week of battery life was terrible but after Rooting and adding these things its been fantastic. Also during the normal day I will run the hack MIFI and my EVO still makes it the full day without an issue.
- 07-05-2010, 03:37 AM #72
- 2 Posts
Personally I think the problem comes from many of the free apps in the store. without a task killer I believe that many of them leave services on that collect usage data. Always try to look at what services a app will require and think why it needs them before you install it.
Like FLST2000us I can get 25 hours plus on moderate use. But when I installed certain free games (I won't say which since I have no real proof) I noticed I was down to about 12 hours of use. For the record I have a half root w/ RvU ROM
- 07-05-2010, 04:37 AM #73
- 07-05-2010, 03:18 PM #74
- 36 Posts
When I read the new update addresses battery power, I was hemming and hawing about installing it. I had the phone rooted via unrevoked and had the free wi-fi tether installed. I was loathe to give it up those capabilities, but I was willing to try anything for more battery power. So I took the update yesterday, and my battery draining issues continued. So now I had an unrooted phone w/crappy battery power, so I was pretty much back to where I started.
So, like I said, I was *extremely* skeptical on reading the post about calibrating the battery, but at this point, I was pretty much willing to try anything. So at 12pm CST, I completed the process. 2.25 hrs later, under normal usage, and my battery is @ 94%.
Now I'm a believer, and thanks for posting that information.
- 07-06-2010, 02:02 AM #75