Lithium tests

Lithium. For most psychiatrists, lithium testing is the area of laboratory testing with which they are most familiar. Lithium has a well-defined, narrow serum concentration range (49). For acute mania, therapeutic lithium levels range between 0.5 mEq/L at the low end and about 1.5 mEq/L at the high end. Individual patients, however, may have idiosyncratic responses outside this range. Samples for blood levels should be drawn about four to five half-lives (i.e., 4 to 6 days) after an adjustment in dose, or more frequently if unexpected reactions occur. Blood samples should be collected 10 to 12 hour after the last dose. 

The most harmful contaminant found in lithium is lithium nitride. Lithium nitride is formed on the surface of lithium exposed to the atmosphere, and therefore such exposure must always be avoided. The harmful effects of minor additions of this material to lithium may be seen in Figure 15. The wall of a Type 316 stainless steel container was completely penetrated (32 mils), by way of the grain boundaries, when lithium nitride was added to the lithium test bath. In a standard test with no addition the attack under similar conditions was 2 to 4 mils. 

On the other hand, it is well known that not all chemical elements possess Mossbauer isotopes. This is an important limitation in the lithium battery field, as common electrode materials in commercial products contain Li, Co, C, O, or P, which have no Mossbauer nuclei. Fortunately, other valuable elements in the electrodes of commercial Li-ion batteries can be studied by this technique. Thus, Fe- and Sn-containing active electrode materials and the less commonly studied Ni have been the basis of thorough investigations. Moreover, many other elements, although not always involved in commercial Li-ion products, have been extensively investigated in lithium test cells and possess Mossbauer isotopes. Among these, Zn, Ge, Ru, Ag, Sb, Te, and iodine can be highlighted. This information is summarized in the form of a periodic table In Fig. 28.2. 

Besides the characterization of the pristine electrode materials, MS can give invaluable information about the electroactive atoms in used electrodes. In this way, it has been demonstrated that iron is also active in the doped LiNi02 electrodes, and participates in a Fe " " Fe" oxidation process during the charge process of lithium test cells [7]. 

Maximum capacity achievable for CoSn electrodes in lithium test cells as a function of particle size. 

Bagnall, C., A Study of Type 304 Stainless Steel Containment Tubing From a Lithium Test Loop, Journal of Nuclear Materials, 1981, Vol. 103,104, pp. 639-644. 

Figure 3.7 Charge-discharge branches of lithium test cells using FeC204 [top] and MnCOs [bottom] as initial active cathode material. Reprinted with permission from Ref 21.

Saturated solutions of sodium chloride do not react at room temperatures. At 90-100 C, high concentrations of sodium chloride (above 20 y in a drop) give a precipitate. If, however, small amounts of lithium are also present, a precipitate is formed in a few seconds even at 45-50 C. Obviously, the precipitation of lithium induces that of sodium and the sensitivity of the lithium test may be increased by this stratagem. 

Upon concept down-select to a gas-Brayton system, work on the lithium test ioop project was cancelled prior to commencement of any loop testing. The test loop circuit was removed from the EFF-TF vacuum test chamber and put into storage. The final MSFC close-out report for the lithium test loop is provided in Reference 13-9. 

All the cations of Group I produce a characteristic colour in a flame (lithium, red sodium, yellow potassium, violet rubidium, dark red caesium, blue). The test may be applied quantitatively by atomising an aqueous solution containing Group I cations into a flame and determining the intensities of emission over the visible spectrum with a spectrophotometer Jlame photometry). 

Miscellaneous. Both whiting and hydrated lime are used as diluents and carriers of pesticides, such as lime—sulfur sprays, Bordeaux, calcium arsenate, etc. The most widely used bleach and sterilizer, high test calcium hypochlorite, is made by interacting lime and chlorine (see Bleaching AGENTS). Calcium and magnesium salts, such as dicalcium phosphate, magnesium chloride, lithium salts, etc, are made directly from calcific and dolomitic lime and limestone. 

Dog repeUents available commercially in the 1990s have been generally unsuccessful in laboratory tests. Por example, lithium chloride treatments were usually rejected immediately with no ingestion, and bone oil treatments that contained up to 0.1% of the active ingredient were stiH consumed (93). Oleoresin capsicum [8023-77-6], the essence of red pepper, did have an extended effect on coyotes, even though the deer repeUents mentioned above were attractive to coyotes (93). Although a capsicum-base aerosol repeUent has been described as potentially harmful (94), pepper spray is commercially available in the United States to repel humans, as is Mace. 

Electronic and Electrical Applications. Sulfolane has been tested quite extensively as the solvent in batteries (qv), particularly for lithium batteries. This is because of its high dielectric constant, low volatUity, exceUent solubilizing characteristics, and aprotic nature. These batteries usuaUy consist of anode, cathode polymeric material, aprotic solvent (sulfolane), and ionizable salt (145—156). Sulfolane has also been patented for use in a wide variety of other electronic and electrical appHcations, eg, as a coil-insulating component, solvent in electronic display devices, as capacitor impregnants, and as a solvent in electroplating baths (157—161). 

Figure 9.20 shows the setup for a symmetric plate impact test. The projectile here has a facing plate of ceramic and is backed with a low-density foam, for support of the ceramic during launch. The facing plate of the target is also made of ceramic. The lithium fluoride slab, which backs the target sample, serves as a window for the laser velocity interferometer (VISAR) that measures the time-resolved particle velocity at the sample/window interface. 

There are many ways to eharaeterize the strueture and properties of carbonaceous materials. Among these methods, powder X-ray diffraetion, small angle X-ray scattering, the BET surfaee area measurement, and the CHN test are most useful and are deseribed briefly here. To study lithium insertion in carbonaeeous materials, the eleetroehemieal lithium/earbon eoin eell is the most eonvenient test vehicle. 

Freshly assembled lithium/carbon coin cells typically have voltages between 2.8 and 3.4 volts. The cells are in their fully charged state which means that no lithium is inserted in the carbon anode. Then the coin cells are tested with computer-controlled constant-current cyclers having currents stable to 1%. The cells are placed in thermostats at a particular set temperature v/hich is stable to 0.1°C during the test. Most of our cells were tested at 30°C. 

Two electrochemical lithium/carbon cells were made for each of the pyrolyzed materials. We used currents of 18.5 mA/g (20-hour rate) for the fust three charge-discharge cycles and 37 mA/g (10-hour rate) for the extended cycling test. 

Observations of current pulses from shock-loaded, x-cut quartz in the vicinity of and above the Hugoniot elastic limit provided rather remarkable confirmation of the nature of the phenomena resulting from mechanical yielding and shock-induced conduction. Lithium niobate provides another opportunity to test the generality of the models. 

As a general procedure, a mixture of the steroidal ketone (50 mg) and lithium aluminum deuteride (20 mg) in dry ether (5 ml, freshly distilled from lithium aluminum hydride) is heated under reflux until the reduction is complete according to thin layer chromatography test. The excess deuteride is then decomposed by the careful addition of a few drops of water and the reaction mixture is worked up by the usual procedure. For hindered ketones or esters the use of other solvents, such as tetrahydrofuran or dioxane, may be preferable to allow higher reaction temperatures. 

Loop Tests Loop test installations vary widely in size and complexity, but they may be divided into two major categories (c) thermal-convection loops and (b) forced-convection loops. In both types, the liquid medium flows through a continuous loop or harp mounted vertically, one leg being heated whilst the other is cooled to maintain a constant temperature across the system. In the former type, flow is induced by thermal convection, and the flow rate is dependent on the relative heights of the heated and cooled sections, on the temperature gradient and on the physical properties of the liquid. The principle of the thermal convective loop is illustrated in Fig. 19.26. This method was used by De Van and Sessions to study mass transfer of niobium-based alloys in flowing lithium, and by De Van and Jansen to determine the transport rates of nitrogen and carbon between vanadium alloys and stainless steels in liquid sodium. 

The Acetate Ion. For the B-coefficients of lithium acetate and potassium acetate, which are of course completely dissociated in aqueous solution, Cox and Wolfenden obtained at 25°C the values +0.397 and +0.238. These large values could be due entirely to the large size of the molecular ion or could be due partly to the fact that the anion produces order in its co-sphere. To test this, Laurence and Wolfenden measured the B-coefficient of acetic acid in aqueous solution at 25°C. 

Reference electrodes are usually a calomel or a silver-silver chloride electrode. It is advisable that these be of the double-junction pattern so that potassium chloride solution from the electrode does not contaminate the test solution. Thus, for example, in titrations involving glacial acetic acid as solvent, the outer vessel of the double junction calomel electrode may be filled with glacial acetic acid containing a little lithium perchlorate to improve the conductance. 

Figure 37. Practical test results of a 2CR5 lithium-manganese dioxide battery in a fully automatic camera at 23 °C.

Lithium cycling on a lithium substrate (Li-on-Li cycling) is another frequently used Li half-cell test [28], in which an excess of lithium (Qex is plated on a metal working electrode, and then constant-capacity cycling (<2ps) Qps is smaller than Qex) is continued until all the excess lithium is consumed. The FOM can be evaluated as shown in Eq.(4). 

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