Thinkpads Forum

I just found out about this battery that you can snap onto the dock connector to give you 2.5 of extra battery life...

Part #40Y7005

Has anyone used this, and is it worth it?
Also, does it really add 3.4cm thickness to the laptop? Wouldn't that double the laptop's thickness?

Hi, I have a 4-cell, and 8-cell, and one of those extended life batteries. It does add quite a bit of thickness but only at one end of the laptop, i.e. at the rear, and from there it pretty much slopes downwards and ends about half way along the bottom. So basically when you're using it in laptop/landscape mode, the battery acts as a stand, pushing the whole computer up at a slight angle (which some people prefer when typing).

When you use the latop in tablet/portrait mode, it's a bit more awkward, because it adds a lot of weight (and thickness) at one side of the machine. I find I can use the tablet comfortably in tablet mode with the extended battery only when resting the machine on my lap. It is impossible to use on the table because it will lie at an angle. Especially when used with the 8-cell battery, the machine becomes very 'side-heavy' in tablet mode, which might put some people off.

I'm not sure what you are asking when you are asking if it is worth it. Do you mean the extra miles per gallon, so to speak? That should be fairly easy to work out, because you can check the price and the capacity. I use all three batteries all the time, so for me it is worth it. Basically with a tablet my idea is that I take the computer by itself with me to work/play during the day, with NO cables or any extras of any kind (just throw it in my bag), and have it on standby constantly, charging it at night. With these three batteries, I can do that. And I can charge all three at once - two while on the lappy itself, and a third plugged into a Lenovo battery charger.

Hope that answers your questions!

PS. Don't believe the battery life claims. I get max 4 hours from the 8-cell, about 1.5 hours from the 4-cell, and probably another 1.5 hours from the extended. That's using wi-fi/GSM off and on throughout the day, and battery stretch off (i.e.screen brightness at a reasonable level).

That's practically impossible!

Do you have the T7500 at maximum performance w. screen on max, Bluetooth on, Wifi on, and HDD spinning non-stop? That could be the drain of battery. Or maybe it's just vista.

It's not Vista...with Vista Premium I get over 8 hours no problem with the 8-cell.