Extending Battery Life on X220?

I just got the X220t with the slice battery and love it.

However, I notice that when my computer is running on only battery life it drains the slice first and then moves onto the regular battery. In addition it brings the slice down to 0 battery before moving on. It seems to me that it would be healthier for the batteries to both be used at the same time so each one ends up being charged equally in frequency, and for either of the batteries, but specifically the slice to never be completely discharged. Are my thoughts correct? Is there any way to do this?

 

I guess one possibilility is that the slice is not actually drained to 0 but is effectively 0 because it was programmed to avoid an unhealthy state. Maybe someone more knowlegable can enlighten me?

 

I agree with you, but I'm not familiar with the battery slice options. Did you look in the advanced settings -> battery -> battery maintenance of the ThinkVantage power manager?

 

I checked battery maintenence and it seems that there are no options that have to do with the interactions between the batteries. I can only configure each seperately. Even then, I see no way to set a minimum charge for the battery before it is considered "empty".

 

This is how Lenovo has always handled charging/discharging for bay/slice batteries. Post a thread in lenovo's forum, maybe they can do something about it.

 

I'm not so surprised about my first issue, but the fact that I can't set a minimum discharge is surprising. Granted I've never had an extended battery before.

 

I think the logic behind draining the secondary battery first is that once it is empty one can change it for another without needing to power down the computer.

However, the question of threshold for stopping the discharge is a valid one. It is possible that the controller electronics for the secondary batteries take this into account such that 0 isn't fully discharged. Has anyone noticed whether the batteries last as well as the main batteries?

John