Theoretically there shall be no problem to run the laptops off the 12V
batteries.  Depending on the models of the notebooks you might have to check
the real voltage these notebooks are using internally.  Externally they
might run on 19, 15V adapters but I suspect that these voltages are for the
case when they have to run at very low AV voltage (universal adapaters
100-240V).  You might need to check the pin arrangements of the adapters.
If the adapters just have to pins (+ and ground) then it will be easy, but
DELL 3 pin adapters, I do not know what they are.  Having a certified
techinican checking will be better.

Cheers

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