Estimated Time to 100% battery

[Strife89]

This isn't quite a feature idea, but here goes.

The Sansa c200s (and perhaps other targets that I'm unaware of) simply show "99%" on the battery percentage level during charging, and the time remaining is shown as 1 second. I know that (at least on the c200s) the voltage level of the battery cannot be monitored during charging, but hear me out.

I don't know what other targets do, but I propose that an estimate system be tried. Based on the battery level at the time the device is plugged in, Rockbox could show the user an estimate of the current battery level as it charges, as well as the estimated time remaining.

Obviously, this would require several benchmarks to be implemented properly, but what do you think? I, for one, am constantly bothered by the not knowing of how much longer until my battery's charged, especially if I am anxious to get moving (i.e., I can't just sit there near the power source).

Opinions, please. Or corrections to my "facts".

[saratoga]

I, for one, am constantly bothered by the not knowing of how much longer until my battery's charged, especially if I am anxious to get moving (i.e., I can't just sit there near the power source).

You may not realize that charging isn't linear.  Your battery quickly charges most of the way, and then charges very little for the last hour or two.  Time remaining isn't going to be very useful in deciding when you can remove the battery if you can tolerate a 90% charge rather then 100% charge.

[Llorean]

I'd be surprised if many peoples' "normal" use habit includes enough use time to run a battery to empty with barely enough time to recharge it to full between uses. And if there's not enough time to charge it between uses, there's simply not enough time to charge it, and you're still restricted to charging it simply "as much as there was time for."

My recommendation - if you're anxious to get moving, get moving. You're not going to be able to delay 'moving' enough to significantly alter your play time anyway if the need to go is causing you to be anxious already.

[dreamlayers]

Target specific powermgmt files have percent_to_volt_charge arrays.  Maybe those can be tweaked to get a better estimate of battery percentage while charging.