Results 1 to 6 of 6
  1.    #1  
    I think i read on this forum that the more you let the battery drain before recharging, the worse it is for the battery. Before reading that post, I had always heard that you should drain a battery as far as possible before recharging. Which is right, or does it make any difference?
    Treo 800w - Love the Phone Can Tolerate the Battery
  2. leonidm's Avatar
    Posts
    189 Posts
    Global Posts
    191 Global Posts
    #2  
    batteries use different technologies and different technologies require different strategies. I believe NiMH was the one that had "memory problem" and needed to bi discharged completly often. Those are rarely used those days and more and more replaced with LiIon ones that do not have this problem. So also battery itself doesn't really care, from practical perspective it make sense to have phone plugged in to charger any time you can and use it on battery when you can't
  3.    #3  
    Cool. Now all i need is a portable battery pack to wear on my back and I'll be all set
    Treo 800w - Love the Phone Can Tolerate the Battery
  4. #4  
    These battery myths started a long time ago.

    NiCd's:

    -LifeSpan: = 1000-1500 Recharge cycles
    -Hi Current Applications
    -Needs full (not complete) discharge/recharge cycyles to have maximum lifespan (to avoid Memory effect)

    NiMh:

    -LifeSpan: = 500 + Recharge Cycles
    -Handles partial charges and recharges from partially discharged batteries better than NiCd's (Less Memory effect)

    Li-Ion:

    -LifeSpan: = About 2 years Typical.. the lifespan for Li-Ion batteries is not based on the number of cycles... but instead on the chemistry of the battery.
    -Little or no Memory effect
  5. #5  
    Quote Originally Posted by leonidm View Post
    So also battery itself doesn't really care, from practical perspective it make sense to have phone plugged in to charger any time you can and use it on battery when you can't
    but the battery that comes with the 800w does indeed care how much it is drained. each drain reduces maximum charge ability. lilons maximum charge are affected by this, age, and temperature extreme.

    again, usage of the battery permanently reduces its full charge mah by slight increments.

    for example if you buy two laptops with the type of battery we have, and drain and discharge one by 25 to 50% each day, and keep the other plugged in, in two months the one with the battery used and recharged will have a measurably lower maximum charge.

    so with the battery tolerance so low on the 800 w you are going to want to keep it plugged in as much as possible.
  6. #6  
    Quote Originally Posted by ndnguy85 View Post
    -LifeSpan: = About 2 years Typical.. the lifespan for Li-Ion batteries is not based on the number of cycles... but instead on the chemistry of the battery.
    -Little or no Memory effect
    no. in one year a liIon losses about 25% of maximum charge ability whether it is in a device or sitting on a shelf in perfect temperature conditions. Drop in mah max is know to be 2% (cumulative) per month.

    when you say number of cycles doesn't make a difference you are kind of repeating a myth yourself. yes, it isn't the number of cycles inherently, but cycles do kill liIons it is just the amount matters.

    so if you discharge a liIon battery by 10% ten times, it harms the battery, but it does so the same as four 25% discharges.

    reductions in loIon max charge ability:
    1) age (2%/month)
    2) discharge cycles x amount of discharge (net use)
    3) temperature extremes

    again, you get 300 to 400 discharge cycles on a liion before it is a goner. in th ecase of liion cycles refer to net draw to maximum ie charging from 25% ten times a week = .75 x 500 or 375 net cycles. meaning everyone will be buying batteries within 12 to 16 months. comparisons to laptops are meaningless because they tend to sit plugged in and probably only discharge 10% per day for almost all users. most people only keep their cellphones in to charge for a couple of hours.
    Last edited by aero; 07/26/2008 at 02:24 AM.

Posting Permissions