Well, not quite. However, by building a little black box you can use a 12 V mains adapter to charge a car battery
To charge a lead-acid battery with a laptop power adapter you will need a DC-DC converter with the proper programming to do a 3 stage (constant current-constant voltage-constant float voltage) charge.
R1 = (Vout/2.77 – 1) * R2
R3 = 0.45 / I
Note: Vin ≥ Vout + 2
The circuit above is taken from the L200C datasheet: