Nickel-hydrogen system

The nickel-hydrogen system has not been studied in such detail. The isotherm at 25°C is presented in Fig. 3 on the basis of the results obtained by Baranowski and Bochenska (11a). The /3-phase of nickel hydride appears when H/Ni exceeds 0.04 at an equilibrium pressure of 3400 atm. The characteristic H/Ni ratio in the /3-phase then amounts to 0.6. 

Fig. 16. Example of a A s.p. = f(t) relation, manifesting surface potential changes in a nickel-hydrogen system as a function of time and amount of hydrogen introduced onto a surface of a nickel film deposited at liquid nitrogen temperature hydrogen-nickel film interactions were studied by Tompkins-Eberhagen static condenser method at liquid nitrogen temperature. After Dus (60). Each dose of H2 — 2.5 X 10 molecules.

In order to study the effect of absorption in the nickel-hydrogen system in more detail, Beeck et al. (11) have investigated the hydrogen sorption isobars between 20°K. and room temperature. As shown in Fig. 6, the solid curves represent the isobars for increasing and decreasing temperature. With increasing temperature (the part between 20 and 80°K. will be discussed later), sorption increases fast between 80 and... 

Sih er-Hydrogen Cells. With the development of the nickel-hydrogen system limited attention was directed to the development of a silver-hydrogen cell. The main characteristics of interest were the potential... 

In measuring dipole moments of an adsorption bond various methods have been reported in literature (19-22), and wide discrepancies exist in the results. For the nickel-hydrogen system we chose the photoelectric... 

Combining the nickel cadmium and nickel-hydrogen systems technologies has given rise to the nickel-metal hydride rechargeable battery, one of the most advanced rechargeable systems commercially available and an environmentally friendlier alternative to nickel-cadmium batteries. The cell and its reaction may be written ... 

The sinusoidal disturbance is particularly useful when the surface being investigated is expected to be heterogeneous, and particularly, as in the case of the nickel-hydrogen system, when the settling times involved in simultaneously occurring adsorptions range from seconds to the order of a day. 

Fig. 7a. Experimental phase lag—active nickel-hydrogen system.

Fig. 7b. Experimental Amplitude ratio—active nickel-hydrogen system.

We feel that a thorough study of the nickel-hydrogen system, as well as other adsorbing systems, is yet to be made since these experiments were performed primarily for the purpose of determining whether the technique is suitable for separating and observing adsorption phenomena. 

The most expensive of the conventional-type secondary batteries are the silver batteries. Their higher cost and low cycle life have limited their use to special applications, mostly in the military and space applications, which require their high energy density. The nickel-hydrogen system is more expensive due to its pressurized design and a relatively limited production. However, their excellent cycle life under conditions of shallow discharge make them attractive for aerospace applications. The cost of cylindrical lithium ion batteries has been decreasing rapidly as production rates have increased and has recently been stated to be S1.22/Wh. ... 

Various Ni-H2 battery designs have evolved through the years. They are tailored to the specific application and interface with the particular satellite. Mechanical and thermal requirements are the primary drivers for the configuration and interface of each battery. The nickel-hydrogen system is sensitive to temperature and performs best between - 10°C and -H 10°C. Thus, thermal control of the battery is important to minimize size and weight. 

As an indication of possible future developments in nickel—cadmium sealed battery design, there follows a brief discussion of one such design under development by Eagle Picher in the USA. This cell incorporates the superior recombination design provisions of the nickel-hydrogen system. The evolution of this hybrid... 

These batteries are still at or slightly beyond the experimental stage. The basic nickel-hydrogen system consists of a catalytic gas electrode (negative) coupled with a nickel electrode (positive). Electrochemically... 

The advantages of the high-pressure design are demonstrated in the volume parameters. A volumetric energy density of 183Wh/dm and a volumetric capacity of l46Ah/dm are achievable with the nickel-hydrogen system. 

Table 19.4 presents comparative data on energy density for the four designs of nickel-hydrogen system discussed above data are also given for silver-hydrogen systems. 

A low-cost nickel-hydrogen system proposed by Eagle Picher is based on the multiple cell per single battery pressure vessel concept. Additional system cost reduction is proposed through use of standardized components, ease of manufacture and an inherent design versatility able to meet various voltage and capacity requirements with only minor modifications. 

The nickel-hydrogen system has been widely studied due to its important applications in chemical catalysis and in hydrogen storage. The difference... 

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