Lithium, biomedical applications

Recently, our laboratory produced a foldable, bendable, and cutable postage-stamp-sized battery (Fig. 12.2). The device looks like a simple sheet of black paper, but it could spell a revolution in implantable battery technology (Pushparaj et al., 2007). The paper battery, a one-piece-integrated device is made of cellulose with CNT and lithium electrodes. The device is flexible, rechargeable, and has the ability to function over a wide range of temperatures giving it a wide variety of potential biomedical applications. As a biomaterial, this paper battery may be useful as a pacemaker because it could easily be inserted under a patient s skin. 

Applications. Polymers with small alkyl substituents, particularly (13), are ideal candidates for elastomer formulation because of quite low temperature flexibility, hydrolytic and chemical stability, and high temperature stability. The ability to readily incorporate other substituents (in addition to methyl), particularly vinyl groups, should provide for conventional cure sites. In light of the biocompatibility of polysiloxanes and P—O- and P—N-substituted polyphosphazenes, poly(alkyl/arylphosphazenes) are also likely to be biocompatible polymers. Therefore, biomedical applications can also be envisaged for (3). A third potential application is in the area of solid-state batteries. The first steps toward ionic conductivity have been observed with polymers (13) and (15) using lithium and silver salts (78). 

Takeuchi, E.S. and R.A. Leising. 2002. Lithium batteries for biomedical applications. MRS Bulletin. August 624-627. 

The lithium/silver vanadium oxide system has been developed for use in biomedical applications, such as cardiac defibrillators, neurostimulators and drug delivery devices. Electrochemical reduction of silver vanadium oxide (SVO) is a complex process and occurs in multiple steps from 3.2 to 2.0 V. This system is capable of high power, high energy density and high specific energy as is required for cardiac defibrillators, its principle application. 

High-rate designs are employed in cardiac defibrillators, while moderate rate units find applications in implantable neurosimulators and drug infusion devices. Lithium/SVO batteries are employed for biomedical applications and as such must be produced under the Good Manufacturing Practices (GMP) for medical devices of the U.S. Food and Drug Administration. 

Donoso et investigated the lithium dynamics of a series of polymer electrolytes formed by PEO, chitosan (OO), amino propil sUoxane (pAPS) and lithium perchlorate by means of Li NMR. Chitosan has been under extensive research on account of its specific properties, such as biocompatibility, and because of its promising potential for biomedical applications. 

Proc. Symp. on Power Sources for Biomedical Implantable Applications and Ambient Temperature Lithium Batteries (Eds. B. G. Owens, N. Margalit), The Electrochemical Society Proceeding Series, PV 80-4, The Electrochemical Society, Princeton, NJ 1980, p. 321. [561 V. R. Koch, J. Electrochem. Soc, 1979, 126, 181. 

Fig. 4.6 Voltage recovery of a lithium anode at -20°C in 1 mol/dm3 LiClO in PC versus a lithium reference electrode. Current density = 10 mA/cm2. (By permission of the Electrochemical Society N. Margalit and H.J. Canning, Proceedings of the symposia on power sources for biomedical implantable applications and ambient temperature lithium batteries, eds B.B, Owens and N, Margalit, 1980, p. 339.)...

Power Sources for Biomedical Implantable Applications and Ambient Temperature Lithium Batteries, 1980. (Ed. B.B. Owens and N. Margalit.)... 

Owens, B. B. and Margalit, N. (eds.) Proceedings of the Symposia on Power Sources for Biomedical Implantable Applications and Ambient Tmnperature Lithium Batteries, Princeton The Electrochemical Society 1980... 

G. M. Phillips and D. F. Untereker, Phase Diagram for the Poly-2-vinylpyridine and Iodine System, in B. B. Owens and N. Margtilit (eds.), Proc. Symp. on Biomedical Implantable Applications and Ambient Temperature Lithium Batteries, vol. 8(14, Electrochemical Society, Princeton, N.J., 1980. 

Phillips GM, Untereker DF (1980) In Owens BB, Margalit N (eds) Power sources for biomedical implantable applications and ambient temperature lithium batteries. The Electrochem Soc Proc Ser PV 870-4, p 195... 

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