- rebuild old laptop battery pack--- waste of time or worth it? - 2 Updates
- my washing machine, again - 2 Updates
"Benderthe.evilrobot" <Benderthe.evilrobot@virginmedia.com>: Jan 18 07:57PM "David" <devotedobserver@thesky.net> wrote in message news:o5njru$t61$2@dont-email.me... > that's for this type of battery. > If all else fails, I'll just continue using the AC adapter. > Thanks. Apparently - some types have configuration data in volatile memory; if you remove the old cells without providing a sustaining voltage, the onboard controller chip becomes *VERY* dumb. Presumably this can also happen if the battery gets completely dead - but all the books are telling me that writes off the cells anyway. |
mike <ham789@netzero.net>: Jan 18 07:50PM -0800 On 1/18/2017 11:57 AM, Benderthe.evilrobot wrote: > Apparently - some types have configuration data in volatile memory; if > you remove the old cells without providing a sustaining voltage, the > onboard controller chip becomes *VERY* dumb. That's been my experience. Only had one successful rebuild. That pack had a PIC processor and resetting it restored functionality. There are other issues. You can't solder to the cells. If you get tabbed cells and try to solder those together, the cells probably won't fit back into the plastic. I used a tab welder for all my experiments. If you buy a "new" battery, it has probably been sitting in a container in Arizona for a decade or two. If it works at all, it probably won't be much better than what you have. If you have it professionally rebuilt, make sure to verify that they can reset the chip so it will work in your computer. For that vintage laptop battery, there are likely tools that let you reprogram the protection chip after a rebuild. Last I looked into it, the cost of the software was several times the cost of a new battery. If you can tolerate the AC adapter, just keep using it. > Presumably this can also happen if the battery gets completely dead - > but all the books are telling me that writes off the cells anyway. But, back to the question. There are some things you can try. If you have the test equipment, you can take the lid off the pack and rebalance the cells. That's safest for the cells, but very much more dangerous for you if you don't know what you're doing. There are calibration procedures that discharge the cells flat by running the computer until it quits, then recharge to full without interruption one or more times. Problem with that is that if the cells are badly imbalanced, you can cause the pack to shut down completely and refuse to recharge. The primary failure of laptop batteries is increased internal series resistance. The electrons are in the battery, but the protection circuits won't let you have them. The symptom is that the battery gauge says 100%, and seems to be discharging normally, but at some point drops abruptly to zero. If you turn off the battery features that sleep or shutdown the system at some battery level, the laptop may run for very much longer. Problem is that it shuts down abruptly and you lose whatever you're doing and may have to chkdsk the drive to clean it up. Once you become accustomed to how long it will run, you can often manage that process manually. The other problem is the same as the calibration issue. Discharged to flat, the pack may permanently disable itself. There are applications that can read the pack registers and tell you what the battery thinks its condition is. It's very dependent on the battery and the sensors in the laptop and the software. You have to try several to see if any work on your system. I've had some success with PC Wizard. Versions 2008 thru 2012 were most helpful. Newer is not necessarily better for this function. May have to try them all. Are we having fun yet? |
Jon Elson <jmelson@wustl.edu>: Jan 18 03:27PM -0600 Jon Elson wrote: I've replaced the valves, again, and the relay, Waiting a few > days to see if the trouble recurs. Well, it's been over a week, the machine is running great. So, problems solved until next time! (Yes, there always seems to be a next time!) Jon |
bruce2bowser@gmail.com: Jan 18 04:09PM -0800 And if you want, some junk yards and metal recyclers have a we-buy-all-appliances policy. Call today. |
You received this digest because you're subscribed to updates for this group. You can change your settings on the group membership page. To unsubscribe from this group and stop receiving emails from it send an email to sci.electronics.repair+unsubscribe@googlegroups.com. |
No Response to "Digest for sci.electronics.repair@googlegroups.com - 4 updates in 2 topics"
Post a Comment