The basic preferred characteristics of PHEV batteries can be summarized as follows [6]:
(1) High specific energy which results in higher AER and less recharge cycles required.
(2) High specific power which results in high acceleration characteristics of the PHEV due to high rates of currents available from the battery without causing any permanent damage to the battery pack.
(3) High number of charge/discharge cycles available and high safety mechanisms built into the battery because of high power ratings of battery packs.
(4) Environmental friendly aspect of the battery, i. e., being recyclable and including low amounts of toxic materials.
(5) Cost is also an important concern for commercializing EVs and PHEVs in a large scale.
