The short answer is: Whichever type fits your laptop.
Laptop batteries vary according to the model and type of laptop computer for which theyve been designed. All laptop batteries do, however, share some common characteristics that differentiate them from regular household batteries:
Laptop batteries are rechargeable
They are composed of multiple internal cells
Within each laptop battery is a small printed circuit board
Shape and location of terminals differ from model to model.
As is the case with all batteries, laptop batteries create an electrochemical reaction, forcing a stream of electrons from one position to another. Also like other batteries, laptop batteries have positive and negative terminals that receive and send electrons.
Rechargeable batteries are more complex, however, than standard batteries. This is because the electrochemical reaction that provides power must be reversible. Care has to be taken when recharging them to ensure they perform at their best.
Frank McLarnon, Lawrence Berkley labs staff scientist explains it this way to Scientific American.com:
“When a battery is discharged, an...