Liquid cathode lithium batteries

The lithium thionyl-chloride battery uses liquid thionyl chloride (SOCI2) as its positive active material, and lithium metal as its negative active material [56]. The overall reaction of the battery is expressed as  

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One variant of the liquid cathode reserve battery is the lithium-water cell in which water serves as both the liquid cathode and the electrolyte. A certain amount of corrosion occurs, but sufficient lithium is provided to compensate. These cells are mostly used in the marine environment where water is available or compatible with the cell reaction product. Common applications are lor torpedo propulsiuu and to puwer sonobuoys and submersihles. 

An inspection of Tables 1 and 2 shows that appropriate solvents for lithium batteries mainly belong to classes 6 and 7 and include cyclic (EC, PC) and open-chain (DMC, MEC, DEC, MPC) esters and ethers (DIOX, DME, THF) as well as inorganic sulfur compounds (S02, SOCl2). These sulfur compounds are mainly used as liquid cathode materials, simultaneously serving as solvents (S02C12, SOCl2) or cosolvents (S02) in primary or secondary lithium batteries. Recent developments of solvents include... 

Wang et al. [96] constructed a Na/S battery with a sodium metal anode, liquid electrolyte, and a sulfur (dispersed in polyacrylonitrile) composite cathode and tested its electrochemical characteristics at room temperature. The charge/discharge curves indicated that sodium could reversibly react with the composite cathode at room temperature. Average charge and discharge voltage was 1.8 and 1.4 V, respectively. Similar to lithium batteries, dendrite formation was noted as a critical problem for these cells. 

The lithium sulfur dioxide and the lithium thionyl chloride systems are specialty batteries. Both have liquid cathode reactants where the electrolyte solvent is the cathode-active material. Both use polymer-bonded carbon cathode constructions. The Li-S02 is a military battery, and the Li-SOCl2 system is used to power automatic meter readers and for down-hole oil well logging. The lithium primary battery market is estimated to be about 1.5 billion in 2007. 

Li/S02 Cells Lithium/sulfur dioxide cells (Li/SC>2) are perhaps one of the most advanced lithium battery systems. They belong to the soluble cathode cells category. Liquid SO2 is used as cathode a lithium foil is used as anode, and lithium bromide dissolved in acetonitrile is used as electrolyte. The active cathode material is held on an aluminum mesh with... 

As seen in the previous section there are numerous types of lithium batteries. In this section, we shall look at the generic hazards of primary (with liquid or solid cathode) and rechargeable batteries. There is much controversy over the reactivity of several individual chemistry types. It is the authors opinion that there are inherent hazards associated with any battery type or energy source and in most situations the hazards and size are directly related. In a similar scenario, lithium batteries in general cannot be categorized into being more or less hazardous than any other chemistry without knowing the exact type and size of the systems to be compared. 

Batteries containing lithium are listed as miscellaneous hazardous materials. The storage batteries are composed of lithium, sulfur, selenium, tellurium, and chlorine. These batteries have four-digit UN identification numbers assigned depending on the use and composition of the battery. Lithium batteries contained in some kind of equipment have the four-digit number 3091. Batteries with liquid or solid cathodes, not in any kind of equipment, are given the number 3090. 

Li, C. Gu, L Xsukamoto S. vanAken, PA. Maier J., Low-Xemperature lonic-Liquid-Based Synthesis of Nanostructured Iron-Based Fluoride Cathodes for Lithium Batteries, Adv, Mater, 2010, 22, 3650-3654. 

The active cathodic material is an intercalation compound, namely a compound with an open structure which allows reversible insertion-deinsertion of lithium ions from-to the electrolyte medium. This makes intercalation compounds very suitable electrodes for rechargeable lithium batteries [10] and indeed they are currently used for this purpose in liquid electrolyte sytems [11]. In the case of the LPBs of interest here, the electrochemical discharge process may be described as the dissolution of lithium at the anode, the migration of the Li" ions across the PEO-LiX electrolytic membrane and its insertion within the structure of the hosting intercalation compound IC ... 

Solid Electrolytes. A protected Lithium anode is under development for both primary and secondary batteries that promise much larger capacities. This strategy is illustrated by the Li/seawater primary battery in which a Lithium anode is immersed in a nonaqueous electrolyte, the anolyte, that is separated from seawater contacting a cathode current collector by a Li -ion solid-electrolyte separator. The seawater acts as a liquid cathode. Except for contact with a negative post, the Lithium anode and its anolyte are sealed in a compartment containing a Li -ion solid-electrolyte wall that interfaces the seawater. The anolyte is chemically stable to both the Lithium and the solid electrolyte the solid electrolyte must not be reduced on contact with the Li anode. Moreover, eiflier the seal or the compartment must be compliant to allow for the change in volume of the Lithium on discharge. The seawater is not ccmtained in an open cell, it is contained within a battery in a closed cell. The LF ions from the anode react with water at the cathode current collector ... 

Ionic cathode batteries. Ionic cathodes are being developed mostly for use with liquid electrolytes, in particular for lithium batteries. 

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