Lithium negative electrode materials

An Li-Al Alloy was investigated for use as a negative electrode material for lithium secondary batteries. Figure 41 shows the cycle performance of a Li-Al electrode at 6% depth of discharge (DOD). The Li-Al alloy was prepared by an electrochemical method. The life of this electrode was only 250 cycles, and the Li-Al alloy was not adequate as a negative material for a practical lithium battery. 

Both hard and soft carbons are used as negative electrode materials for lithium-ion batteries. Hard carbon is made by heat-treating organic polymer materials such as phenol resin. The heat-treatment tempera-... 

As mentioned above, the typical positive electrode material is LiCo02, and there are typically two types of negative electrode materials, such as coke and graphite. The characteristics of lithium-ion batteries constructed using these electrode materials are discussed below. 

Lithium-titanium-oxide spinels provide a relatively low voltage of 1.5V vs. lithium. They are, therefore, of interest as possible negative electrode materials for lithium-ion cells [161-163] they can be coupled, for example, to Li[Mn2104 (4V vs. Li) to yield a 2.5V lithium-ion cell, or to LixMn02 (3V vs. Li) to yield a 1.5V lithium-ion cell. Although these cells have a voltage lower than that of commercial... 

The recent development of the convertible oxide materials at Fuji Photo Film Co. will surely cause much more attention to be given to alternative lithium alloy negative electrode materials in the near future from both scientific and technological standpoints. This work has shown that it may pay not only to consider different known materials, but also to think about various strategies that might be used to form attractive materials in situ inside the electrochemical cell. 

Joho F., Novak P., and Spahr M.E. Safety Aspects of Graphite Negative Electrode Materials for Lithium-Ion Batteries. J. Electrochem. Soc., 149,1020-1024 (2002). 

Anani A., Crouch-Baker S., Huggins RA. Kinetic and Thermodynamic Properties of Several Binary Lithium Alloy Negative Electrode Materials at Ambient Temperature. J. Electrochem. Soc. 1987 134 3098-101. 

Anani A, Crouch-Baker S, Huggins RA. Kinetic and thermodynamic parameters of several binary lithium alloy negative electrode materials at ambient temperature. J Electrochem Soc 1987 134 3098-3102. 

At the same time, it was found that Li metal is an unsafe negative electrode material [11, 13]. Upon charging a battery, lithium is electrodeposited on the Li metal electrode. During this process, formation of dendrites was observed, and after multiple charge/discharge cycles, those dendrites penetrated the separator and led to an internal short circuit of the cell with intense heat formation and sometimes even combustion of the cell. 

Poizot P, Laruelle S, Grugeon S, Dupont L, Tarascon JM. Nano-sized transition-metal oxides as negative-electrode materials for lithium-ion batteries. Nature. 2000 407(6803) 496-9. 

F yrolysis of gaseous hydrocarbons at 1000-1700 °C is a common route (cf. Nos. 6 and 7 in Table 9, where two examples involving benzene are considered [441, 442]). The substrate was nickel, and dense black layers were obtained to serve as a host lattice for the lithium negative electrode. The pyrolytic carbon from benzene at 1000 °C gave a lithium GIC (CeLi) and could be cycled at 99% current efficiency [407]. Pyrolysis of epoxy Novolac resin and epoxy-functionalized silane gave a material containing silicon with a capacity of 770 mAh/g for the lithiated form [443]. 

Mesoporous tin was deposited from LLC surfactant phases in order to provide a nanostructured negative electrode material for applications in lithium ion batteries. Whitehead et al. [67,68] electrodeposited tin films from lyotropi-cally liquid crystalline solutions of tin sulfate in the hexagonal phase of Brij 76 onto copper foil. The authors further employed n-heptane as an inert swelling agent in order to tailor the dimensions of the resulting electrode materials. 

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