Micro lithium ion batteries

Solid lithium-ion batteries are currently mainly manufactured in micro or mini capacity since they are mainly used for microelectronics. Large-capacity solid lithium-ion batteries are not yet in production, and they will not be discussed here. The positive electrode, electrolyte, and negative electrode for microelectronics should be prepared in multilayers. The manufacturing process for micro-lithium-ion batteries includes the preparation of the positive electrode film, the electrolyte film, and the negative electrode film. 

Suitable electrolytes for lithium-ion batteries should generally be good conductors for Li+ ions and act as insulators for electrons. In addition, electrolytes should not react with Li metal in the range of 0-5 V. Electrolytes suitable for micro-lithium-ion batteries are basically inorganic compounds, which are discussed in Chapter 11, such as oxides and sulfides. 

In the case of some microelectromechanical systems (MEMSs), a solder reflow step is used for their assembly processes, which requires all electronics to be heated above 250°C. At the moment, lithium metal cannot be used as the negative electrode film since its melting point is only 180°C. From the discussion in Chapters 7 and 8, it follows that carbon-based and non-carbon-based materials can be used as negative electrodes. Similarly, they can also act as negative electrode materials for the solid micro-lithium-ion battery. For example. 

Micro-solid lithium-ion batteries are constructed by assembly of the films described in Sections 14.3.1-14.3.3. Several assembly processes are known, but the process used at Oak Ridge National Laboratory is shown in Figure 14.12. The interesting concept of a three-dimensional (3D) micro-lithium-ion battery has been proposed. The main bottlenecks are how to improve the electrochemical performance of the positive electrode and the introduction of solid electrolytes. 

Electrochemical performance of a micro lithium-ion battery based on SnN as the negative electrode, LiPON as the electrolyte, and LiCo02 as the positive electrode (a) Discharge curves at different current densities with thicknesses of 50 and 600 nm for its negative and positive electrodes, respectively and (b) cycling behavior with thicknesses of 10 and 200 nm for its... 

Micro batteries can be assembled in any shape or size and can be combined in different ways for different applications. Although the energy density and output power for micro lithium-ion batteries are not very high, their... 

Micro lithium-ion batteries can be used as either the main or the backup power source of MEMSs. They can be manufactured independent of the MEMS and can be connected externally to the MEMS. They can also be embedded as a power source for one component of the MEMS, which can reduce the power consumption of the integrated circuit. Micro medical devices, remote sensors, mini transmitters, smart cards, biochips, and micro operators for the human body can also use them a as main or backup power source. They also can be used for memory cards and computer complementary metal oxide semiconductors (CMOSs). 

In 2010, the University of California at Los Angles initiated the "salt particle program," whose target is to tailor micro lithium-ion batteries the size of a salt particle. If successful, the micro lithium-ion battery could also be used in portable computers, mobile phones, and media players. 

In the present work, a simulation strategy is formulated to study the performance of cathode materials in lithium ion batteries. Here micro scale properties, for example, diffusion of spherical electrode particle within the periodic boundaiy condition, 0electrode particles move in each step to its nearest neighbor distance, employing the condition ir j) > e -dLi lds ), where ir represents the random number, dLil is the nearest neighbor distance for the Li ion in the absence of solvent and ds being the thickness of the sohd phase. The MC codes involve macro scale properties, namely, solvation effects, diffusion coefficients and the concentration gradient... 

Brun N, Prabaharan SRS, Morcrette M, Sanchez C, Pecastaings G, Derre A, Soum A, Deleuze H, Birot M, Backov R (2009) Hard macrocellular silica Si(HIPE) foams templating micro/macroporous carbonaceous monoliths applications as lithium ion battery negative electrodes and electrochemical capacitors. Adv Funct Mater 19 3136... 

Note 2 The nomenclature assigned to pore dimensions is one which has been inherited over past decades. In the literature, the use of the term nanoporosity is appearing to distinguish it from other porosities. This is where some confusion now arises. The porosities of concern to adsorption processes are the micro- and mesoporosities, with dimensions of <2.0 nm and between 2.0 and 50 nm respectively that is, both have dimensions of nanometers. The terms micro and meso, as such, are essentially only a name and have no significance beyond that. In recent times, interest has centered on porosities in carbons with dimensions < 1.0 nm and which are responsible for the phenomena of activated diffusion (Chapter 4) and uptake of lithium as for the lithium-ion battery (the so-called nanoporosity). The literature also refers to ultra-mieroporosity, of suggested dimensions <0.7 nm as well as super-microporosity assigned to microporosity with dimensions nearer to the limit of 2.0 run, where three or four... 

Zhu G-N, Liu H-J, Zhang J-H et al (2011) Carbon-coated nano-sized Li4Ti50i2 nanoporous micro-sphere as anode material for high-rate lithium-ion batteries. Energy Environ Sci 4 4016 22... 

Zhang L, Wu B, li N, Mu D, Zhang C, Wu F (2013) Rod-like hierarchical nano/micro Ii12Nio.2Mno.6O2 as high prafmmance cathode materials for lithium-ion batteries. J Power Sources 240 644—652. doi 10.1016/j.jpowsour.2013.05.019... 

Menzel M, Schlifke A, Falk M et al (2013) Surface and in-depth characterization of lithium-ion battery cathodes at different cycle states using confocal micro-X-ray fluorescence-X-ray absorption near edge stmcture analysis. Spectrochim Acta Part B At Spectrosc 85 62-70. doi 10.1016/j.sab.2013.04.001... 

Boesenberg U, Falk M, Fittschen UFA et al (2015) Correlation between chemical and morphological heterogeneities in LiNio,5Mni,504 spinel composite electrodes for lithium-ion batteries determined by Micro-X-ray Fluorescence Analysis, Chemistry of Materials, doi 10. 1021 /acs. chemmater. 5b00119... 

Wang Q, Sun JH, Yao XL, Chen CH (2006) Micro calorimeter study on the thermal stabihty of lithium-ion battery electrolytes. J Loss Prev Process Ind 19 561-569... 

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