Lithium rechargeable batteries performance characteristics

Since portable computers have unique characteristics as a result of the portability, they have unique accessories as well. First of all, portable computers can use either of two power sources batteries or AC power. There are many different sizes and shapes of batteries, but most of them are either Nickel-Cadmium (NiCad), Lithium Ion, or Nickel Metal Hydride (NiMH). All of these perform equally well as batteries, but NiCad batteries can only be recharged a finite number of times. After a time, they develop a memory and must be recharged on a special deep charging machine. NiMH and Lithium Ion batteries don t normally develop a memory and can be recharged many times, but they re a little more expensive. 

Lithium-ion batteries have been commercially available for over 2 decades and currently represent state-of-the-art power source for all modem consumer electronic devices. Due to its advanced chemistry, Li-ion cells exhibit superior performance characteristics over most other rechargeable battery systems. The lithium-ion technology offers a high energy and power density, long life, and reliability that makes it attractive for electric drive vehicle (EDV), military, and aerospace fields, and large format Li-ion cells and battery packs are currently under development for such applications. 

Studies performed by the author on various types of rechargeable batteries for EVs and HEVs reveal that lithium-based batteries are widely used by various manufacturers. The most widely used rechargeable batteries include Li-ion-manganese-dioxide, Li-ion-iron phosphate, Li-ion-sulfide, and Li-ion-polymer. Performance capabilities and other important characteristics of these batteries are described in great detail in this section, with a particular emphasis on energy density, selfdischarge rate, longevity, and power density. 

The LiMnOj battery is the most popular lithium battery, and it is produced worldwide by more than 14 manufacturers. The battery cells are available in a wide range of sizes, shapes, and capacities. Types of construction features for this battery include coin shape, cylindrical bobbin, cylindrical wound, cylindrical D cell configuration, and prismatic feature. Performance characteristics of commercially available LiMn204 rechargeable batteries are summarized in Table 8.2. 

As with primary lithium batteries, a number of different approaches have been taken in the chemistry and design of rechargeable lithium batteries to obtain the desired performance characteristics. These are summarized in Fig. 34.1a for batteries with lithium metal negative electrodes (the anode during discharge) and in Fig. 34.1fc for batteries with other materials, such as lithium alloys and lithiated carbon. ... 

The different types of ambient-temperature lithium metal rechargeable batteries have been classified into four design categories. These are identified in Table 34.10, which lists representative chemical systems and the key advantages and disadvantages of each class. The components and chemical reactions and the performance characteristics of typical examples... 

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