The life span of a hybrid car battery is supposed to be as long as the life span of the car itself, but the practice shows that you frequently have to change individual cells. The battery is usually located in the trunk, behind the rear seat.
The battery should be changed by a garage specializing in handling hybrid cars
The cost of changing a hybrid car battery is still very high, although it is gradually decreasing. Make sure you check its condition before you buy a second-hand hybrid car