Lithium electrolyte additives

Lithium carbonate addition to HaH-Heroult aluminum ceU electrolyte lowers the melting point of the eutectic electrolyte. The lower operating temperatures decrease the solubiHty of elemental metals in the melt, allowing higher current efficiencies and lower energy consumption (55). The presence of Hthium also decreases the vapor pressure of fluoride salts. 

Secondary lithium-metal batteries which have a lithium-metal anode are attractive because their energy density is theoretically higher than that of lithium-ion batteries. Lithium-molybdenum disulfide batteries were the world s first secondary cylindrical lithium—metal batteries. However, the batteries were recalled in 1989 because of an overheating defect. Lithium-manganese dioxide batteries are the only secondary cylindrical lithium—metal batteries which are manufactured at present. Lithium-vanadium oxide batteries are being researched and developed. Furthermore, electrolytes, electrolyte additives and lithium surface treatments are being studied to improve safety and recharge-ability. 

Films on lithium play an important part in secondary lithium metal batteries. Electrolytes, electrolyte additives, and lithium surface treatments modify the lithium surface and change the morphology of the lithium and its current efficiency [93],... 

There have been many attempts to improve the cycling efficiency of lithium anodes. We describe some of them below, by discussing electrolytes, electrolyte additives, the stack pressure on the electrode, composite anodes, and alternatives to the lithium-metal anode anode. 

There have been many studies with the goal of improving lithium cycling efficiency by the use of electrolyte additives. These additives can be classified into three types ... 

An overview about more than 10 years of R D activities on solid electrolyte interphase (SEI) film forming electrolyte additives and solvents at Graz University of Technology is presented. The different requirements on the electrolyte and on the SEI formation process in the presence of various anode materials (metallic lithium, graphitic carbons, and lithium storage metals/alloys are particularly highlighted. 

Solid electrolyte interphase (SEI), electrolyte additive, lithium ion battery, Li metal, graphite, lithium alloy. 

In fact, crystalline graphites usually cannot be operated in PC electrolytes, unless effective film forming electrolyte additives are used (see above) as propane gas evolution [35], creation of solvated graphite intercalation compounds (sGICs) [36], and graphite exfoliation take place. Recently [37, 38], it was found that propylene evolution is observed at graphite, while absent at lithium active metallic anodes, e.g., Sn and SnSb. 

Wrodnigg G. H., Besenhard J. O., Winter M., Ethylene sulfite as electrolyte additive for lithium-ion cells with graphitic anodes, J. Electrochem. Soc. (1999), 146 (2), 470-472. 

Polymer electrolytes have been shown to stabilize the lithium/electrolyte interface, yielding stable and low interface resistance, especially when ceramic additives such as y-LiA102 are used. Furthermore, the 7-LiA102 ceramic additive has been shown to stabilize the polymer amorphous phase and to slow down the recrystallization process [99-103]. Thus, the unique electrochemical performance of lithium metal can be applied in practical devices by substitution of the liquid electrolyte with a solid one whose conductivity and stability can be enhanced with ceramic additives. 

Uses Buffer mfg. of lithium stearate and other lithium soaps lubricating greases carbon dioxide absorbent (for submarines and space vehicles) esterification catalyst photographic developer stabilizer source of Li-6 isotope (used in prod, of tritium) in alkaline batteries (electrolyte additive) corrosion inhibitor in steam boilers dispersant in water-based alkyd paints leather ceramics buffer in cosmetics hair waving or straightening... 

Pandey, G. P., and S. A. Hashmi. 2013. Solid-state supercapacitors with ionic liquid based gel polymer electrolyte Effect of lithium salt addition. Journal of Power Sources 243 211-218. 

Fig. 5b. It has the typical golden color of LiC. This means that the additive has decomposed dnring the eqnihbration cycles and has deposited at the active sites of graphite, preventing the formation of metallic lithium. We believe that electrolyte additives improve the performance of the graphite electrodes by changing the kinetics of elemental lithium deposition. Because the electrolyte additives make the usage of highly crystalline graphite anodes possible and at the same time suppress the coexistence of elemental Li along with the hthiated graphite, they are considered to be a key material in the LIB industry.

There are many books reviewing the liquid electrolytes for hthium or lithium-ion cells, where the various properties of aprotic solvents, lithium salts, and their mixtures are described. " This author also reviewed them mainly from the aspect of solution chemistry.However, recent researches in the liquid electrolytes are mainly focused on the electrolyte additives, which add extra functions to the liquid electrolytes in addition to a fundamental function as an ionic conductor. This author will attempt to outline the electrolyte additives for the first time by classifying them into several categories, although the fragmented information on the additives began to appear in the recent reviews. In addition to the information pubhshed in the hterature during 1991-2004, some experimental results obtained in our laboratories also are included. 

There is by far less information available on the cathode interface than the anode interface. However, the reports appeared recently, which insisted that there is a film on the cathode, which may be called a SFI as well as the anode." Since the oxidative reactions on the cathode cannot immobilize reaction products like the reductive reactions on the anode, the amount of SFI on the cathode is much smaller than that on the anode, as demonstrated in Fig. 4.11. Due to the analytical difficulties, a very few data in the literature report the effects of electrolyte additives on the cathode. It was reported that the addition of VC reduced the interfacial impedance and improved a bit the rate capability. It was speculated that this effect is caused by the polymer formation by VC on the cathode, which suppresses the deposition of lithium fluoride, since this effect disappeared when VC contained polymerization inhibitors such as BHT. This is reasonable because the oxidation potential of VC is lower than those of other carbonate solvents. ... 

Graphite has competition reactions especially at low temperature one is a lithium intercalation into its structure and the other is the hthium deposition on it, which means the rather low intercalation reaction kinetics. Another important and interesting result reveahng the importance of the electrolyte additives is shown Fig. 5, representing a graphite anode after the completion of six cycles under the... 

W. M. Lamanna, A. Xiao, M. J. Triemert, P. T. Pham, Int. Patent Appl. WO 2012170240 Al, 2012. Lithium ion electrochemical ceUs including fluorocarbon electrolyte additives. 

S. S. Zhang, J. Power Sources 2006, 162, 1379-1394. A review on electrolyte additives for lithium-ion batteries. 

D. Moosbauer, S. Zugmann, M. AmereUer, H. J. Gores, J. Chem. Eng. Data 2010, 55, 1794-1798. Effect of ionic liquids as additives on lithium electrolytes Conductivity, electrochemical stability, and aluminum corrosion. 

Y. Zhu, Y. Li, M. Bettge, D. P. Abraham, J. Electrochem. Soc. 2012, 159, A2109-A2118. Positive electrode passivation by LiDFOB electrolyte additive in high-capacity lithium-ion cells batteries and energy storage. 

Y. Qin, Z. Chen, J. Liu, K. Amine, Electrochem. Solid-State Lett. 2010, 13, A11-A14. Lithium tetrafluoro oxalato phosphate as electrolyte additive for lithium-ion cells. 

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