With modern Lithium ion batteries its because as their capacity decreases over time the BMS can’t always keep up and recover the 100% point unless you’re occasionally draining it all the way. This can result in someone charging their battery to say 97% and leaving it for hours to reach a 100% it will never reach. This is potentially unsafe as it heats up the battery.
You’re probably already familiar with this resource, but Battery University has some interesting and useful information about batteries and it’s accessible enough for the layperson.
That was the original reason. Ni-cad batteries develop a “memory” if they aren’t fully discharged loose capacity.
With modern Lithium ion batteries its because as their capacity decreases over time the BMS can’t always keep up and recover the 100% point unless you’re occasionally draining it all the way. This can result in someone charging their battery to say 97% and leaving it for hours to reach a 100% it will never reach. This is potentially unsafe as it heats up the battery.
Edit: Autocorrupt beansed up my comment
You’re probably already familiar with this resource, but Battery University has some interesting and useful information about batteries and it’s accessible enough for the layperson.