Power Tools for Technical Communication: Headings Practice

In this lab, you add headings to a technical document:
  1. Copy the text below this box, and paste it into your preferred word-processing software.
  2. Add the following headings at the appropriate points in the text and at the appropriate levels (use second- and third-level headings):
    Types of batteries
    Lead-acid batteries
    Nickel-base batteries
    Lithium-base batteries
    Just use bold on these headings; no other typographic effects are required.
  3. Put your name, Headings Practice: Print, and the date on this document, and either print it out or show it on screen to your instructor, or send it be e-mail attachment to your instructor.

Batteries are an essential component of the HEVs currently under development. Although a few production HEVs with advanced batteries have been introduced in the market, no current battery technology has demonstrated an economical, acceptable combination of power, energy efficiency, and life cycle for high-volume production vehicles. The Partnership for a New Generation of Vehicles program has established technical targets for the program's hybrid battery development efforts for power-assist and dual-mode HEVs.

Desirable attributes of high-power batteries for HEV applications are high-peak and pulse-specific power, high specific energy at pulse power, a high charge acceptance to maximize regenerative braking utilization, and long calendar and cycle life. Developing methods/designs to balance the packs electrically and thermally, developing accurate techniques to determine a battery's state of charge, developing abuse-tolerant batteries, and recycleability are additional technical challenges.

Lead acid batteries, used currently in many electric vehicles, are potentially usable in hybrid applications. Lead acid batteries can be designed to be high power and are inexpensive, safe, and reliable. A recycling infrastructure is in place for them. But low specific energy, poor cold temperature performance, and short calendar and cycle life are still impediments to their use. Advanced high-power lead acid batteries are being developed for HEV applications.

Although nickel-cadmium batteries, used in many electronic consumer products, have higher specific energy and better life cycle than lead acid batteries, they do not deliver sufficient power and are not considered for HEV applications. Nickel-metal hydride batteries, used routinely in computer and medical equipment, offer reasonable specific energy and specific power capabilities. Their components are recyclable, but a recycling structure is not yet in place. Nickel-metal hydride batteries have a much longer life cycle than lead acid batteries and are safe and abuse-tolerant. These batteries have been used successfully in production EVs and recently in low-volume production HEVs. The main challenges with nickel-metal hydride batteries are their high cost, high self-discharge and heat generation at high temperatures, the need to control losses of hydrogen, and their low cell efficiency.

The lithium ion batteries are rapidly penetrating into laptop and cell-phone markets because of their high specific energy. They also have high specific power, high energy efficiency, good high-temperature performance, and low self-discharge. Components of lithium ion batteries could also be recycled. These characteristics make lithium ion batteries suitable for HEV applications. However, to make them commercially viable for HEVs, further development is needed similar to those for the EV-design versions including improvement in calendar and cycle life, higher degree of cell and battery safety, abuse tolerance, and acceptable cost.

Lithium polymer batteries with high specific energy, initially developed for EV applications, also have the potential to provide high specific power for HEV applications. The other key characteristics of the lithium polymer are safety and good cycle and calendar life. The battery could be commercially viable if the cost is lowered and higher specific power batteries are developed.

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