Does suddenly cutting power off harm my T400?

I rarely use my laptop outside my house, so I decide to take away the battery and use AC power directly. However, sometimes power cut off occurs in my location. Does this harm my laptop's harware? Thanks in advance!

 

Won’t harm the hardware, but does dramatically increase your chances of data loss/corruption.

 

Data loss and HD corruption is more likely to happen.

 

Always keep the battery in.

 

Thanks

What do you mean by HD corruption?

One of my friend said that doing this will reduce the battery's life span somewhat. Is it true?

 

Probably. You'll have to decide what is more important to you - the battery life or your data/convenience. Batteries are a consumable whether they're in your car, your flashlight or your notebook. Eventually they will die and need to be replaced.

 

If you are worry about the battery life span, just set new charging thresholds in Power Manager so that the battery isn't fully charged. Keeping the battery charged at around 40% is probably the best way to keep maintain battery health.

This is a unique feature of ThinkPads that your friend probably doesn't know about. So leave the battery in, but just don't tell your computer to charge it all the way.

 

One of the best things about a notebook is having battery backup. No data loss/corruption due to power loss, no work interruptions.

 

I agree with the others, leave the battery in and use it. Thats what it is for. You can help to extend the life with charging thresholds but the battery will still deteriorate even if not being used.

 

Following up on this post, the specific way to do this is to launch the ThinkVantage Power Manager. Go to the Battery Information tab, then click the "Battery Maintenance" button. Choose the "Optimize for battery lifespan" option, and also select "Notify me when thresholds change".

This way, you can keep your battery all the time yet not worry that you are causing it to deteriorate by doing so.

 

I've changed my thresholds from 96 - 100 to 80 - 90.

topping the batt. reduces lifespan, but I want to be able to get
6-7 hours min. so 80/90 seemed ok

 

80-90 will work, but if you leave it plugged in all the time and want to maximize lifespan you should pick something closer to 40%. Li-ion batteries degrade quickly even if unused when they are stored at close to full charge. This is particularly true if they get warm (attached to a hot running laptop). I would recommend you set 30-50% thresholds for daily use, and when you think you will need battery power just change it to 30%-100% and top it off before you go. I use my laptop on battery almost every day so I use a higher threshold of 60%-95% because I can't be bothered by needing to charge it for an hour before I can unplug to get the battery life I need.

 

Thanks all! So, with this unique feature ThinkPad is just awesome