4.1　Introduction

Text（课文）

Energy storage systems（ESS）play an important role in EV，HEV and PHEV.The performance of these vehicles is highly dependent on the ESS.There are a few types of energy storage options available for different vehicle applications.Nickel Metal Hydride batteries have been widely used in HEVs in the past ten years.Lithium ion batteries are considered as the only viable solution for EV and PHEV at the present time.Ultracapacitors also have been investigated for use in PHEV due to their very high power density and long cycle life.Flywheel-based HEVs also have been investigated.Integrated hybrid energy storage systems that contain high energy lithium ion batteries and high power ultracapacitors could potentially provide the best solutions for EV and PHEV.Proper management of the ESS in EV，HEV，and PHEV can not only extend the life of the battery ESS，but also help improve overall fuel efficiency of the vehicle.

New words and expressions（单词和短语）

1.New words（单词）

2.Expressions（短语）

Notes to the text（难点解析）

★1.There are a few types of energy storage options available for different vehicle applications.有几种不同类型的储能选择，可以用于不同的车辆应用。

★2.Proper management of the ESS in EV，HEV，and PHEV can not only extend the life of the battery ESS，but also help improve overall fuel efficiency of the vehicle.对电动汽车、混合动力汽车和插电式混合动力汽车储能系统的适当管理不仅能延长电池储能系统的寿命，还可以提高汽车整体的燃料效率。

Exercises（练习）

◆1.Translate the following passages（expressions）into Chinese（英译汉）

（1）Ultracapacitors also have been investigated for use in PHEV due to their very high power density and long cycle life.

（2）play an important role

（3）energy storage systems

★2.Translate the following passages（expressions）into English（汉译英）

（1）锂离子电池

（2）镍金属氢化物电池

（3）储能系统（ESS）在电动汽车、混合动力汽车和插电式混合动力汽车中发挥着重要的作用。

Reading material（阅读材料）

According to DOE PHEV Meeting Summary Report（2006），the battery warranty cost is believed to be one of the show-stoppers for the mass market penetration of PHEV.Tesla Motors provides only 3 years of warranty on their EV battery.Others charge＄300/year for battery warranty beyond 3 years.It is estimated that the replacement cost of the Chevy Volt battery pack is more than＄10，000，The EV and PHEV battery will have a warranty of 10/150（10 years or 150 k miles，whichever happens earlier）in the“green states”in the United States，which is due to CARB regulations allowing a＄3，000 incentive if a PHEV battery has the 10/150 warranty.Equally，if not more important than warranty cost is the customer perception of battery life and the impact on resale value（and residual value）of the car.