09-19-2012 05:43 PM
09-19-2012 05:53 PM
09-19-2012 06:16 PM
09-19-2012 07:26 PM
05-30-2017 08:56 AM
Zygomorphic wrote:
It was necessary with the old "dumb" batteries and the nimh/nicads. Modern lithium batteries do smart charging, which eliminates the need for calibration.
10-16-2023 10:55 AM - edited 10-16-2023 11:01 AM
The reason for "cycling" Ni-Cds at higher current levels was to prevent the formation of dendrites, that could form shorts within the cells. IIRC, much of the myth surrounding Ni-Cds, came out of reports from NASA who were charging and discharging the cells in a very specific manner. I understand that they withdrew the claims of battery "memory" although the idea remains. The capacity of LiPos, has little to do with the charging method, although one can destroy the cells by "mischarging", they can however only stand so many charge cycles. This will be stipulated by the manufacturers. A cycle usually means returned to a full charge, not a top-up. Li-pos will also happily discharge themselves if stored with a high charge. Very annoying!
I should add that the "smart Charging" simply means that currents are maintained as a % of C more often than not, not more than 1C, and cells are maintained within a few millivolts of each other to prevent discharges in compound batteries, which could lead to high current flow and thermal runaway. Look out jumbo jet!
10-16-2023 10:13 AM
@cl-scott Don't take it personally, but this is not the same thing at all. Calibration enables the system to understand what a full charge is! Li-Po batteries lose their ability to take a full charge over time - this has nothing to do with the erroneous Ni-Cd battery memory. By timing how long it takes a battery to discharge, while measuring current, one (the laptop) can establish how much energy a "full charge" contains and so can then give a meaningful indication of the amount of power available. One can do this to some degree, by matching the voltage slope (knowing current) and compare it to an ideal battery.
You will note that some systems have a dedicated battery calibration function.
One agrees that their is a lot of regurgitated nonsense out there!
09-19-2012 10:03 PM
09-20-2012 05:39 PM
c_man wrote:
BatteryBar constantly monitors the status of your battery as you use your laptop. As it monitors your battery, it keeps historical data on your battery and provide you with a very accurate estimate of how much time is remaining on your battery.
I just use this http://osirisdevelopment.com/BatteryBar/
It does a good job on all the laptops so far.