I love when people do these kinds of things
Things to keep in mind.
The drill battery pack is rated for a specific capacity which may only be able to run the laptop for only a short period of time.
The drill battery pack's voltage will slowly decline... so the laptop's internal voltage regulation may be stressed or pushed out-of-spec resulting in system instability.
A power supply is a power supply. As long as you ensure certain specifications are accounted for, you will be fine.
Certain details can be overlooked or flexed, but there is not way to determine for sure without intricately knowing how the device electronically operates. It is always best to match the 'requested' specifications for a power supply.
If you're going to do something, do it right.
I would only ever recommend this for getting a laptop running that is considered garbage already, or if this is an emergency situation.
As an aside... would you pour vegetable oil in your gas tank (if the engine was diesel)
It's considered a 'bio-fuel'
** Nothing against bio-fuels... but this is not something that any regular Joe should do with no prior knowledge or understanding of how it operates.