Electrodes negative electrode materials

The discharge of alkaline-manganese batteries comes from the electrochemical reactions at the anode and cathode. During discharge, the negative electrode material, zinc, is oxidized, forming zinc oxide at the same time, Mn02 in the positive electrode is reduced (MnOOH) ... 

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-... 

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. 

COMMERCIAL NEGATIVE ELECTRODE MATERIALS 7.6.1 Hard Carbons... 

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. 

Only rare-earth system (AB5-type) and zirconium-titanium-vanadium system (AB2 Laves phase-type) hydrogen storage alloys have been used as negative electrode materials for the commercial production of Ni-MH batteries [3, 7, 8], However, these materials have a low hydrogen storage capacity resulting in a low electrode energy density. 

Lighter negative electrode materials per unit charge (Li in particular, also Mg and Al), therefore higher gravimetric and volumetric energy densities. 

Nonaqueous batteries can be designed to meet an almost unlimited variety of uses. This results from the great flexibility of choice regarding solvents, active materials, i.e., positive and negative electrode materials, and supporting electrolytes. 

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. 

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