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Dell batteries are programmed to die after a set time, how to hack battery?

  • Hi. My Inspiron 6400 battery could hold about 2 hours of charge a week ago. However, now it can only last 15 minutes. It seemed to have just died overnight! I realize that lithium ion cells do degrade with time, but they DO NOT suddenly undergo such sudden decay in a short period of time. Lithium ion batteries decay exponentially, and clearly this is not exponential behavior. I also find that the battery could charge from 50% to 100% in a very short period of time compared to before. It is also coincidental that my battery would die a few months after my warranty expired. Such facts lead me to believe that my battery is equipped with circuity that is making the cell appear dead, when the cells itself are actually holding more charge than displayed. My theory seems to be confirmed after doing a bit of research. In fact, after taking apart my battery, the lithium cells are actually holding a fairly normal voltage, indicating that there is nothing wrong with them. Read this:

    http://www.west-wind.com/WebLog/posts/365.aspx

    No, I am not trying to start a conspiracy. It appears that I am not the only one to have my battery seem to die overnight like this. Searching other notebook forums, I have found similar incidents by other Dell notebook users as well. So I would like to know what is going on exactly and how to get around it. I know there are ways to take apart the battery and manually interface with the battery circuitry to clear the data on how old the cell is, how many cycles its gone through, etc... I am just wondering if anyone has any experience with this, or maybe if you had other methods to get around this issue, please share.

    I already realize that lithium ion will degrade, but in the case of dell batteries, the circuit is ELECTRONICALLY preventing the cells from being operated at their capacity and thereby forcing users to prematurely have to buy new batteries. I dont want to buy another battery from Dell only to have it mysteriously die again a month after its warranty ends.

    Advice and comments are welcome, thanks.

    Message Edited by nobb on 10-09-2007 11:11 PM
  • I've had Dell batteries last over 3 years and still keep a charge.  I don't think it's time for the tin foil hat.  You've taken the battery apart and I assume measured the voltage across the cells.  There's a difference between voltage and power.  It may be that the fully charged battery is at the correct voltage but it may not be able to deliver the current (power) it originally could.  It could also be one bad cell which is limiting the amount of current the battery can supply.
     
    One interesting point is if you read the Dell Precision Workstation specifications here, they rate the battery life as 300 charge/discharge cycles.  That doesn't sound like much.
     
    The good thing is the battery hasn't exploded yet. :smileyvery-happy:
     
     
     

  • Man, that's a good one.
  • Having had to recall millions of batteries, Dell is no doubt being conservative with the current models. Are you willing to bypass the safety mechanism and risk an explosion or fire, with the possibility of losing your home, health and/or life, for the sake of a $150 battery?

    Lithium ion technology is inherently dangerous. The safeguards are there for a reason.
  • Yes I am aware of the potential threats of lithium ion technology. Perhaps it was misleading that my thread title is suggesting that all Dell batteries are like this. But the fact of the matter is that I am not the only user who has experienced this mysterious loss of battery capacity overnight. I have also read of a few users actually successfully bypassing the circuit which counts the number of charge cycles (and resetting it), so lets try to keep an open mind here on what is actually happening.

    I am NOT suggesting to bypass some of the critical safety features (such as temperature monitoring, etc...). To falsely PREVENT a battery from operating at its potential after a certain number of cycles/time is NOT a safety feature (although it can be argued). iPods and mp3 players dont rely on circuitry to deliberately do this to their batteries and they are still safe, so why should my laptop do so?

    By resetting the chip, I merely want to set the number of cycles back to 0 so that the computer wont think the cells are dead, when it actually is not. The critical safety features will still be in place.
  • And you're sure the problem isn't a safety related issue such as a failed cell that would cause overheating because ...?
  • If it was just a single cell that failed (or multiple), I dont think it would even be able to charge. That is not the case with my battery. After doing some reading, it appears to be a known fact that several manufacturer's deliberately "electronically kill" the battery pack after a set time/cycle. However, I have yet to find any source that suggests that operating a lithium battery after 500+ cycles poses a safety hazard, so I dont understand why manufacturers insist upon this practice, other than to force the consumer to buy more batteries.
  • " I dont understand why manufacturers insist upon this practice, other than to force the consumer to buy more batteries. "
     
    Litigation for negligence when someone is hurt or worse is expensive.
     
    pcgeek11
  • Ok...like I said...lets try to keep an open mind about this issue. I love my Dell notebook just like you guys, but this is a serious issue that I feel needs to be acknowledged and not just ignored because you guys think "the manufacturer knows what is best". Yes lithium ions are dangerous...but the manufacturer simply does NOT need to deliberately make the battery pack appear dead when the cells are actually functioning just fine (just not new). Lithium ion cells are perfectly safe even when they age...they just dont hold as much charge.

    Here is more evidence to backup my claim that the battery is making the cells appear dead when they are actually fine:

    I took apart my battery (it was fully charged) and cut all the wires going to the cells (i thought that would clear the memory). When I reconnected the wires, the battery would not operate (due to the anti-tampering mechanism). However...doing a quick search on the BQ29312 chip...I learned that I could "turn the pack on" simply by applying 5 volts to a specific pin. Yup..that worked and my battery worked...but the "memory" was not cleared and it still showed I only had 20 mins of battery life. So this time, I tried the procedure again...except that I fully discharged the battery down to 0% (according to the BIOS). So after I applied 5 volts to the chip...my battery powered on...but was not recognized by the BIOS. It says that my battery is not installed...but strangely..when I pull the plug...my laptop runs just fine from the battery. Remember how I previously said that the BIOS said my battery was at 0%? Well...after the procedure (didnt add any more charge to the battery)...I WAS ABLE TO GET OVER AN HOUR more of battery life by simply letting my laptop run from the battery which was supposedly at 0%.

    Therefore, it is apparent that the cells are actually capable for 1.5 hours (the amount of time I could get before this incident), when the battery pack is only allowing for 20 mins.
  • I have an Inspiron 1300, and my battery "died" overnight 2 month out of warranty (went from 2hrs to 15 minutes). I popped the battery open and measured each cell. They were all ok. I linked the pack to a light bulb through an amp meter and computed the time it would need to discharge if they were full charged. Guess what, they ran the time I computed they would. So, yes, they are "programmed" to fail out of warranty. just do a search on "inspiron 1300 battery" and you'll be surprised at how many wrote about the fact that the battery die just out of warranty. And it's a complete nonsense to buy a new $180  battery pack for a $500 computer every  year...

    I didn't knew about this reset procedure. Will sure try it.