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[INFO] *UPDATED -17 June 09* Battery life problems? Stop here!

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By bauerpavel, Senior Member on 28th May 2009, 12:38 AM
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This is a "Quick guide" to your battery - APPLIES TO Li-ion BATTERIES ONLY! (simplified version of an older thread http://forum.xda-developers.com/show...73#post3834773 )

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This info doesn't come from me but from 2 (I believe trustful) sources:
Isidor Buchmann,CEO of Cadex Electronics Inc., in Vancouver BC, award winning author of many articles and books on batteries,has studied about rechargeable batteries for 2 decades
Fran Hoffart, Applications Engineer, Linear Technology, Milpitas, California

Original web sites:
http://www.batteryuniversity.com/partone.htm
http://www.buchmann.ca/faq.asp
http://powerelectronics.com/portable...-battery-0425/
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Charging tips
  • partial-discharge cycles can greatly increase cycle life, and charging to less than 100% capacity can increase battery life even further
  • after a full charge, a Li-ion battery will typically lose about 5% capacity in the first 24 hours, then approximately 3% per month because of self-discharge and an additional 3% per month if the battery pack has pack-protection circuitry
  • no need to charge for 5+ hours for the first time (priming), this doesn't work for li-ion chemistry
  • use ONLY ORIGINAL or HTC CERTIFIED chargers and batteries (they have extremely important function of cutting off
    the current when charging is at 100% * )
  • battery cannot be reconditioned by over-charging - avoid higher than 4,2V current (which might boost capacity but shorten cycle life)
  • no need to worry about memory effect with "unscheduled" charging
  • avoid soft reseting your phone while charging
  • allow several full charges after doing hard reset to get accurate reading
  • try to keep battery stress as low as possible when charging (sure shot is to charge the phone when turned off)
  • a deliberate full discharge and recharge every 30 charges corrects "wrong reading" phenomena in most cases, if ignored, the battery gauge will become increasingly less accurate
  • using battery chargers that feature a reduced float voltage (4-4.1V) can increase battery life when used to charge a 4.2V Li-ion battery

Discharging tips
  • full discharge cycles (down to 2.5 V or 3 V, depending on chemistry) should be avoided if possible (except for above mentioned case of recalibrating device)
  • using only 20% or 30% of the battery capacity before recharging will extend cycle life considerably. As a general rule, 5 to 10 shallow discharge cycles are equal to one full discharge cycle
  • avoid frequent full discharges, very deep discharges will quickly, permanently damage a Li-ion battery
  • avoid high-stress discharging, slower discharge=better battery life
  • discharge level doubles with every 10°C (18°F) of increased enviromental temperature


Usage tips
  • avoid extreme load conditions (applications using a lot of energy)
  • avoid keeping a fully charged battery at high temperatures
  • battery stored for a year or more will start "aging" - irreversible
    capacity lowering
  • maintaining a Li-ion battery in a fully charged condition will shorten its lifetime
  • store batteries charged at 40%
  • replace battery if original level drops bellow 80%, battery will lose about 10% of useful capacity each year (whether used or not)

* Selecting a charger that uses minimum charge-current termination (C/10 or C/x) can also extend battery life by not charging to 100% capacity. For example, ending a charge cycle when the current drops to C/5 is similar to reducing the float voltage to 4.1 V (see fig.3 bellow). In both instances, the battery is only charged to approximately 85% of capacity, which is an important factor in battery life. The letter “C” is a battery term used to indicate the battery manufacturers stated battery discharge capacity, measured in milliamp-hours. For example, a 2000-mAhr rated battery can supply a 2000-mA load for one hour before the cell voltage drops to its zero-capacity voltage.

Types of Li-ion batteries:


Charging dependencies:



The Following 8 Users Say Thank You to bauerpavel For This Useful Post: [ View ] Gift bauerpavel Ad-Free
 
 
28th May 2009, 01:21 AM |#2  
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Thank you for a very informative post. Very good info here.
28th May 2009, 08:32 AM |#3  
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How can I full discharge my battery? Simply left my TP on until it dies? I am wondering that if it is wrong reading battery level, maybe it switch itself off when it reads 0% but maybe the real battery level is..10% or 15%, how can I be sure that the battery is full discharge? My TP is 3 month old, so, or my battery is damaged, or my TP is not accurate reading battery level; I was forgotting that sometimes I have done some soft reset while charging (but not in the past two weeks)
28th May 2009, 01:18 PM |#4  
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Quote:

avoid soft reseting your phone while charging

Noticed something interesting the other day, here are the series of events that occurred:
- Battery died - phone turned off (is that considered a full discharge?)
- plugged it in, and it started to charge. The lights on the pad began to pulsate.
- Sometime later I realized that the phone was off so I turned it on. Mind you the lights were still pulsating indicating that it was charging. After the Version # screen came up and just before the Windows Mobile screen comes up. The lights which was in the middle of a pulse, stopped, and began again from the start. Is that considered an interruption in charging?
28th May 2009, 03:18 PM |#5  
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This should be a sticky!

The main problem I've come across is an inaccurate battery meter. Quite a few people using RRE WM6.5 have reported battery issues, but I've noticed its the meter, not the actual battery.

I RARELY did a full discharge (and I've had my phone since it came out in November). So after flashing the ROM, I did a full discharge. It stayed on 20% for a long time, then it stayed at 7% for a long time, then it seemed like it was at 1% forever. The phone finally shut off. I did a full charge while the phone was off. Now the battery meter is MUCH more accurate.
28th May 2009, 06:07 PM |#6  
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I'm using RRE's and noticed the "meter" issue. Think I'll give your suggestion a try and let it die over the weekend and juice it back up.

Quote:
Originally Posted by mindfrost82

This should be a sticky!

The main problem I've come across is an inaccurate battery meter. Quite a few people using RRE WM6.5 have reported battery issues, but I've noticed its the meter, not the actual battery.

I RARELY did a full discharge (and I've had my phone since it came out in November). So after flashing the ROM, I did a full discharge. It stayed on 20% for a long time, then it stayed at 7% for a long time, then it seemed like it was at 1% forever. The phone finally shut off. I did a full charge while the phone was off. Now the battery meter is MUCH more accurate.

28th May 2009, 09:33 PM |#7  
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Quote:
Originally Posted by p51d007

I'm using RRE's and noticed the "meter" issue. Think I'll give your suggestion a try and let it die over the weekend and juice it back up.

My phone has been off the charger for about 8.5 hours now. I sent/received about 10 texts, and I've had about 10 emails pushed through Windows Live and my battery is at 92% now. All on Edge with a good signal. Not too bad for me.
31st May 2009, 03:48 PM |#8  
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I just would like to ecourage people to leave their feedback, if they tried some of the tips from this thred. Just to see if they are relevant in "real" life.

THANK YOU ALL!!!!
1st June 2009, 10:38 PM |#9  
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Battery Life
While the Fuze doesn't get the greatest battery life, one thing I immediately noticed was the extension of life when I switched my email from checking every five minutes to once every hour.

Just saying.
2nd June 2009, 02:18 PM |#10  
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Quote:
Originally Posted by mxgoldman

While the Fuze doesn't get the greatest battery life, one thing I immediately noticed was the extension of life when I switched my email from checking every five minutes to once every hour.

Just saying.

Every 5 minutes would cause a huge drain in battery. You would be better off pushing email to your phone than checking every 5 minutes. Once per hour isn't too bad unless you're getting lots of emails every hour.
2nd June 2009, 09:37 PM |#11  
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This is great information...thanks for the tips...and yes, getting emails every five minutes SERIOUSLY drains the battery...i learned that the hard way
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