T60p-Determining which battery draws down first?

[Patrick B]

Ok, so here's my question, and the rationale behind it.


On my T60p, I have the Ultrabay Slim battery, in addition to two (2) 9 cell main batteries.

I travel extensively, and much of it is overseas. Unfortunately, my company tends to stuff me in cattle-class, which more often than not, means no power outlet in the seats.

What I'm hoping to figure out is a way to force the system to discharge the main, 9 cell battery first, THEN switch to the Ultra-bay slim battery, so that I can swap main batteries.

In theory, such an arrangement could give me 10+ hours of non-stop work (or movie watching off the HDD etc).

I realize I can do this the manual way (use the primary battery and leave the Ultrabay battery out until I need it), but I'm looking for an automatic solution, if possible.

Any ideas?

There doesn't appear to be anything in the BIOS, or in the Thinkpad Power Manager.

The reason it's a concern for me, is that when I check Thinkpad Power Manager with both batteries installed, the Secondary battery is the one discharging, not the primary one.


Thanks,



Patrick

[truk]

I don't think I'm catching something here. Either I've misread, missed something, or I'm wondering what everyone has hasn't bothered to ask, but, what difference does it make? There is a total number of cells, current, and voltage to run down. It doesn't seem to me that the order of them makes a difference. What am I missing?

PS-I'm not trying to be rude or ignorant, it is a serious question

[bill bolton]

There doesn't appear to be anything in the BIOS, or in the Thinkpad Power Manager.

Unless there has been a fundamental change in approach with the T6x range from all previous T models, the Ultrabay battery will discharge first and then the main battery will discharge..... and there will be no way to change that.

Cheers,

Bill B.

[barrywohl]

What am I missing?

He wants to swap 9 cell batteries while running off of the Ultrabay battery, but the ThinkPad uses up the Ultrabay battery first. He could pop in the Ultrabay battery when the first 9 cell gets low, but he wants the software to be smart enough to let him choose which battery he uses up first.

Me too.

[Patrick B]

What am I missing?

He wants to swap 9 cell batteries while running off of the Ultrabay battery, but the ThinkPad uses up the Ultrabay battery first. He could pop in the Ultrabay battery when the first 9 cell gets low, but he wants the software to be smart enough to let him choose which battery he uses up first.

Me too.

Exactly.

Yes, I can do it manually, by inserting the Ultra-bay battery when the alarm reaches critical for my Primary battery, but this seems both inefficient and clumsy to me.

If there was a software / firmware solution to this, then that would be perfect. It would allow me to have a "hitless" 8-10 hours of battery life, and only have to swap the Primary 9 cell once.

Wishful thinking, I guess.


Patrick

[deforest]

What I have done with my t40p, which I haven't yet tested with my t60p is performing the following:

Have both main and ultrabay batteries in laptop.

First the ultrabay discharges, then when that is low, the main battery starts discharging.

When the main battery gets low, I put the machine into suspend/sleep mode.

Then I carefully remove and replace the main battery (the ultrabay has the depleted battery in that). During this replacement of the main battery I find that ultrabay battery has enough juice to power the laptop in sleep mode.

Then after the main battery swap is complete, re-awake the thinkpad, and continue where I left off at.

I have done this numerous times on the t40, where I was without a outlet for a day (5 to 6 hours), several times a year. Lately with the t60p I only 3 to 4 hours away for an outlet and haven't even bought an additional 9 cell battery to swap with yet.

[SHoTTa35]

that's what i'm sure he's doing now. What he (and a lot of othre people) would like is to have the option to choose which one to draw power from first. By default the power always comes from the UB battery when both are installed, it would be nice to have the UB battery keep the system running while he takes out the main 9 cell battery and replace it with the other, this is all without putting the system to sleep or hibernate.

I guess that can already be sorta be done, just have the system send a message when the main reaches 10%, you then slide in your UB battery and then your while that one is being used you slide in the other 9 cell main battery?

[Pascal_TTH]

I don't if it's still common but I got a Compal CL50 with a battery backup. It allow to swap main battery while the laptop is in suspend to ram. This battery allow about 3 minutes in STR, just to swap main battery. Nice feature.

Does ThinkPad also have this feature ?

[zhenya]

As others have said, we are unfortunately out of luck in this respect. IMO, an even worse design defect of the ultrabay battery is that it will discharge completely before switching to the main battery, and this also is not user-adjustable. This means that the ultrabay battery loses capacity very quickly. In 18 months, I'm on my 2nd battery, and it now only holds 50% of the original capacity, and is now out of warranty. This is an EXTREMELY poor design that could be fixed rather easily via a software update.