Lithium Corrosion Research Articles

Effect of sodium cation on lithium corrosion in aprotic media (extended abstract)

Effect of sodium cation on lithium corrosion in aprotic media (extended abstract)

Surface film effect on the electrochemical behaviour of active metals

It has been suggested that a film on the surface of an active metal should be a dielectric with low ionic and electronic conductivity. The film-electrolyte boundary can be regarded either as an interface between two electrolytes or as the surface of an insulating electrode. In this zone a potential difference is set up and redox reactions proceed. These processes, controlled by the concentration and by the transfer of charged particles through the film, determine the anode-cathode behavior of metals under consideration. Corrosion and anodic dissolution of lithium and magnesium have been investigated in dilute solutions of water in propylene carbonate. The potential of the lithium electrode reveals the properties of the equilibrium potential and does not depend on either the content of water in the solution or the lithium corrosion rate. The observed orders of interaction between lithium and water, however, does depend on the water concentration, on the electrolyte concentration, and on the thickness of the initial film. At the beginning of the process the rate of the interaction between lithium and water is described by the equations of topochemical kinetics, but when the maximum is reached, by the Tamman equation. A stationary potential is realized on magnesium; its value depends on the water content in the solution. The potential shifts towards negative values with increased water concentration.

Computer simulation of thermal modeling of primary lithium cells

The objective of this program was to gain a better understanding of the safety problems of primary LiSOCl 2 and LiSO 2 cells by carrying out detailed thermal modeling work. In particular, the transient heat generation rates during moderate and extremely high discharge rate tests of LiSOCl 2 cells were predicted and compared with those from the electrochemical heating. The difference between the two may be attributed to lithium corrosion and other chemical reactions. The present program was also evaluated in charging tests of LiSO 2 cells. In addition, the present methodology should be applicable, with minor modifications, to analyses of other primary cylindrical cells as well as rechargeable batteries.

Application of GDOS (glow discharge optical spectroscopy) and SIMS to the analysis of surface corrosion products on stainless steel after exposure to liquid alkali metals

AbstractCorrosion of steels by liquid alkali metals involves the transfer of non metals, such as C, N or O, from solution in the alkali metal to the surface of the steel. Surface corrosion products may then be formed. With oxygen in sodium these products may be ternary oxides, with nitrogen in lithium the ternary nitride Li9CrN5 is formed and with carbon binary carbides are formed in both alkalies. Along with the surface corrosion products, element depletions and carbon or nitrogen diffusion profiles are created. The analyses of thin corrosion product layers and the determination of the concentration profiles of carbon and nitrogen are important requirements for the understanding of the corrosion process. Lithium penetration into steel is also a major problem in lithium corrosion. Lithium is extremely difficult to determine by conventional analytical methods, due to its low atomic number. In this paper the use of glow discharge optical spectroscopy (GDOS) and SIMS for the study of surface corrosion products, is described, together with a quantitative determination of the carbon‐depth profile in type 316 steel exposed to liquid sodium.

Liquid cathode primary batteries

Lithium/liquid cathode/carbon primary batteries offer from 3 to 6 times the volumetric energy density of zinc/alkaline manganese cells, improved stability during elevated temperature storage, satisfactory operation at temperatures from −40 to +150 °C, and efficient discharge at moderate rates. he lithium/sulfur dioxide cell is the most efficient system at temperatures below 0 °C. Although chemical reactions leading to electrolyte degradation and lithium corrosion are known, the rates of these reactions are slow. While the normal temperature cell reaction produces lithium dithionite, discharge at 60 °C leads to a reduction in capacity due to side reactions involving sulfur dioxide and discharge intermediates. Lithium/thionyl chloride and lithium/sulfuryl chloride cells have the highest practical gravimetric and volumetric energy densities when compared with aqueous and most other nonaqueous systems. For thionyl chloride, discharge proceeds through a series of intermediates to sulfur, sulfur dioxide and lithium chloride. Catalysis, leading to improved rate capability and capacity, has been achieved. The causes of rapid reactions leading to thermal runaway are thought to be chemical in nature. Lithium/sulfuryl chloride cells, which produce sulfur dioxide and lithium chloride on discharge, experience more extensive anode corrosion. An inorganic cosolvent and suitable salt are capable of alleviating this corrosion. Calcium/oxyhalide cells have been studied because of their promise of increased safety without substantial sacrifice of energy density relative to lithium cells. Anode corrosion, particularly during discharge, has delayed practical development.

The corrosion susceptibility of 21/4 Cr-1 Mo steel in a lithium-17.6 wt pct lead liquid

Significant penetration at prior austenitic grain boundaries was observed in the heat-affected zones of 21/4 Cr-1 Mo steel GTA weldments after the metal was exposed to 500 °C for short times to liquid lithium containing 17.6 wt pct lead. To prepare larger, microstructurally homogeneous but corrosion-susceptible specimens for detailed study, coupons of 21/4 Cr-1 Mo steel were heat treated so as to simulate the coarse-grain bainitic microstructures found in the heat-affected zones of GTA weldments. The coupons were exposed to Li-17.6 wt pct Pb at various temperatures. Lithium corrosion was found to increase with increasing austenitizing temperature and to be insensitive to quench rate. The penetration kinetics for the corrosion-susceptible microstructures exhibited a change in mechanism which is hypothesized to be associated with the coversion of e-carbide to cementite. The initial penetration mechanism, with an activation energy of 22 kJ/mol, is thought to be controlled by carbon diffusion in liquid lithium. The secondary penetration rate exhibited an activation energy of 117 kJ/mol, which suggests that reaction of lithium with cementite at the grain boundaries might be the rate controlling step.

The influence of cyclic loading on the lithium corrosion behavior of reactor materials

A review of the frequency dependent fatigue-crack-propagation characteristics of 2 1 4 Cr — 1 Mo steel and types 304 and 304L stainless steel shows that liquid lithium enhances crack growth rates in the temperature range of 473K to 973K. These results are significantly different from data for sodium obtained previously by other investigators. A mechanistic interpretation of the effects of lithium indicates that lithium enhances crack growth by inducing embrittlement at low temperatures and by grain boundary penetration at high temperatures. The engineering implications of this study are discussed.

Characterization GF 304-SS and 316-SS exposed to liquid lithium for 10 000 hours

The paper presents the results on post-exposure analysis of specimens from the Lithium Mini-Test Loop operated at Argonne National Laboratory and from capsule experiments at Seibersdorf. Corrosion behaviour depends on the lithium impurity levels, on metallurgical factors (fabrication, mechanical deformation) and presence of MHD effects. It is concluded that under low flow conditions microstructural changes due to lithium corrosion do not appear to be a life-limiting factor for 304-SS and 316-SS within reasonable time periods. However, compatibility studies should continue to derive more quantitative data on impurity and mass transfer effects.

A study of type 304 stainless steel containment tubing from a lithium test loop

The present investigation was undertaken in an attempt to learn more about the characteristics of lithium corrosion. This paper deals with a metallographic evaluation of the type 304 stainless steel (T304SS) 2.5 cm diameter tubing, used for the main loop containment of an experimental lithium facility, and gives a detailed account of hot leg corrosion. This examination, while necessarily qualitative from a corrosion standpoint, was aimed at revealing the nature and degree of attack, the effects of downstream position in an isothermal zone, and the reaction of the liquid metal at welds and weld heat-affected zones.

Liquid Lithium Corrosion Rate Expressions for Type 304L Stainless Steel

Abstract Corrosion rate expressions for weight loss and grain boundary penetration kinetics for Type 304L stainless steel in liquid lithium have been determined as a function of nitrogen concentration in the temperature range of 600 to 1000 C (873 to 1273 K). A list of observations which must be included in the development of a liquid lithium corrosion model for austenitic stainless steel is presented.

ChemInform Abstract: THE ANODIC BEHAVIOR OF LITHIUM IN AQUEOUS LITHIUM HYDROXIDE SOLUTIONS

AbstractDas anodische Verhalten von Li in 3‐5 M LiOH wird bei Raumtemp. unter definierten hydrodynamischen Bedingungen in einem Strömungskanal untersucht.

The Anodic Behavior of Lithium in Aqueous Lithium Hydroxide Solutions

The anodic behavior of lithium in was investigated at ambient temperatures under well‐defined hydrodynamic conditions using a flow channel. The electrode showed a linear polarization behavior up to a mass‐transfer limited anodic current density. The rate of the parallel chemical corrosion of lithium was determined over a range of current densities, flow rates, and concentrations using a gas coulometer to measure the total rate of hydrogen evolution. The corrosion rate approaches zero linearly as the current density approaches the diffusion‐limited level. On the basis of electrode resistance and efficiency, the plane‐parallel electrode configuration was judged suitable for batteries of the lithium‐water type.

Corrosion of Lithium in Alkaline Solution

The corrosion of Li was studied in at 25°C and in at 4°–60°C. The Arrhenius relationship is obeyed and the apparent activation energy for the Li corrosion reaction is found to be 15.5 kcal mole−1. An empirical relationship is derived from which the corrosion rate can be obtained at any molar . At 25°C . An equation is also given which allows calculation of the Li corrosion rate when the metal is anodically polarized. The kinetics of the evolution reaction (e.r.) on Li were determined, the transfer coefficient α has a value of 0.14. The rate‐controlling process of the Li dissolution reaction is the highly polarized evolution at cathodic sites. Based on the α value obtained, the enthalpy of activation for the e.r. on Li at OCV is calculated to be 22.8 kcal mole−1. It is proposed that the protective film on Li has a duplex structure with a thin oxide/ hydroxide layer adjacent to the metal and an outer porous hydrated layer through which the reaction products and reactants can pass freely.

Analytical Determination of Nitride Nitrogen in Lithium Coolants

The corrosion behavior of stainless steels in liquid lithium is affected by the quantities of lithium nitride in lithium coolants. Monitoring the amounts of the nitride in lithium metal is important in the interpretation of liquid lithium corrosion results. Lithium nitride is determined by a titrimetric procedure that measures the ammoniaa evolved when lithium nitride dissolves in water. The ammonia is dissolved by a boric acid solution, which is then titrated with standard hydrochloric acid. (auth)

Polarization Admittance Study of Lithium Corrosion in Propylene Carbonate Solutions

Abstract Lithium metal is relatively stable in pure propylene carbonate and in pure propylene carbonate solutions containing LiBF4 and LiCl. Solvent degradation was encountered in the presence of aluminum chloride resulting primarily in the formation of carbon dioxide and chlorohydrins. The proposed mechanism involves reaction of lithium with the chlorohydrins resulting in a relatively high corrosion rate accompanied by hydrogen evolution. Use of the polarization admittance technique produced data in qualitative agreement with weight loss values. Corrosion rates based on polarization data were higher than those based on weight losses. The lack of quantitative agreement indicates that the conditions imposed on the technique were not encountered in this complex environment.