Energy storage configurations

The decomposition of some materials into smaller, more stable molecules can be initiated by mechanical shock alone, and they are known as shock-sensitive. Many commercially important chemicals are thermally sensitive and decompose with the addition of heat. For storage situations, the critical temperature at which the thermal energy is sufficient to start an uncontrolled reaction in a particular storage configuration for a specified time is known as the self-accelerating decomposition temperature (SADT), as described in NFPA 49. 

Thermal solar collectors are also available in so-called central concentrator or solar concentrator designs. In these configurations, a large number of independently movable flat mirrors (heliostats) are used to reflect the solar radiation onto a central receiver on the top of a tower. Each heliostat moves about two axes. The receiver typically is a vertical bundle of tubes in which the heat-transfer fluid (water or oil or molten salt) is heated by the reflected and concentrated insolation. The molten salt technology also provides thermal energy storage. 

Production lines typically operate at upwards of 500 cells/min or more. The alkaline cell has higher energy storage, longer shelf life, and lower internal resistance than either of the two carbon-zinc cells. The alkaline cells are also produced in coin/button cell configuration as shown in Figure 10.7. 

Conversion of a regenerative PEC to a PECS can incorporate several increasingly sophisticated solar energy conversion and storage configurations, which we shall discuss in this section. 

A BSPM system can incorporate hydrogen production in a number of different configurations. A basic hybrid energy storage system requires several 12 / panels with an approximate 10 amp output. These panels are connected in parallel with a diversion controller. To operate with the higher voltage and to use it efficiently, the system would include a bank of three electrolyzers connected in series (bipolar connection) that will use four volts each. This will be discussed in more detail at the end of the Electrolyzers chapter. 

The main issues of hybrid propulsion systems are discussed in this chapter, drawing attention to basic characteristics of power train components and aspects of energy management within each hybrid configuration. The main characteristics of electric drives are described in Sect. 5.2, different types of electric energy storage systems are analyzed in Sect. 5.3 and Sect. 5.4, while different configurations of hybrid electric vehicles are discussed in Sect. 5.5, with particular reference to fuel cell propulsion systems (Sect. 5.5.4). 

The experimental results discussed in this case study are obtained on a fuel ceU power train installed on a laboratory test bench. It is constituted by a 3.5 kW electric drive connected in hybrid configuration to a 2 kW PEM fuel cell system (FCS) and an electrical energy storage system (lead batteries). The main technical specifications of the FCS are reported in Table 6.1, whereas its scheme is shown in Fig. 6.1 [1, 2]. 

The general theme of electric vehicles is covered in Chap. 5, with particular reference to hybrid vehicles that adopt both fuel cells and batteries/supercapacitors as power sources. The analysis of possible hybrid configurations is presented together with a review of different types of electric energy storage systems. 

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