I don't own that model. But my trick to avoid overheating is simple. I set the power profile to battery mode which slows down the system and CPU and produces a lot less heat. I also make sure it's on a surface that doesn't obstruct airflow.
In regards to batteries. The usual battery hours supplies for ALL laptops is about 2 hours. With a range for a low 1 hour to a high of 4 hours for some unit that just sat there with the display in ultradim mode, that's about it.
does anyone owns a aspire 2001wlmi laptop? how does the machine performs? any problem? heat, hang, etc? can the machine be used for bout 12 hours straight with ac power without overheating? how long does it last on batteries? how are acers machine? can i add a pc keyboard to it?