Lithium rechargeable batteries negative electrodes

In lithium rechargeable batteries carbon materials are used that function as a lithium reservoir at the negative electrode. Reversible intercalation, or insertion, of lithium into the carbon host lattice avoids the problem of lithium dendrite formation and provides a large improvement in terms of cycleability and safety (111). 

While the development of primary cells with a lithium anode has been crowned by relatively fast success and such cells have filled their secure rank as power sources for portable devices for public and special purposes, the history of development of lithium rechargeable batteries was full of drama. Generally, the chemistry of secondary batteries in aprotic electrolytes is very close to the chemistry of primary ones. The same processes occur under discharge in both types of batteries anodic dissolution of lithium on the negative electrode and cathodic lithium insertion into the crystalline lattice of the positive electrode material. Electrode processes must occur in the reverse direction under charge of the secondary battery with a negative electrode of metallic lithium. Already at the end of the 1970s, positive electrode materials were found, on which cathodic insertion and anodic extraction of lithium occur practically reversibly. Examples of such compounds are titanium and molybdenum disulfides. 

FIGURE 34.1 Lithium rechargeable batteries (a) with metalUc lithium as negative electrode, (b) with lithium alloys or lithiated carbon negative electrode. 

These lithium coin cells generally use a metal oxide intercalation compound for the positive active material and a hthium alloy, such as lithium aluminum, which is less reactive than metallic lithium, for the negative electrode. An organic solution is used for the electrolyte. The energy density and specific energy of the different rechargeable lithium coin-type batteries are summarized in Fig. 34.36. 

Carbon-Lithium Rechargeable Batteries. The carbon-lithium batteries use a lithium alloy for the negative active material, a nonaqueous organic electrolyte, such as propylene carbonate, and activated carbon for the positive electrode. The battery is built in a discharged state. The mode of operation and the reactions during charge and discharge are delineated as follows ... 

The design of lithium ion batteries has been a great achievement toward overcoming this defect. In these rechargeable batteries, a carbon matrix material is used instead of hthium as the negative electrode which, during charging, takes up hthium ions by cathodic intercalation ... 

At the end of the 1990s in Japan, large-scale production of rechargeable lithium ion batteries was initiated. These contained lithium compounds intercalated into oxide materials (positive electrodes) as well as into graphitic materials (negative electrode). The development of these batteries initiated a further increase in investigations of the properties of different intercalation compounds and of the mechanism of intercalation and deintercalation processes. 

Due to its high energy density (3,860 mAh/g) and low voltage, lithium is the most attractive metal of the periodic table for battery application. Unfortunately lithium metal, and most of its alloys cannot be used in rechargeable batteries because of their poor cyclability. Therefore, lithium intercalation compounds and reversible alloys are among today s materials of choice for subject application. The most common active materials for the negative electrodes in lithium-ion battery applications are carbonaceous materials. The ability of graphitized carbonaceous materials to... 

Shin HC, Corno JA, Gole JL, Liu M. Porous silicon negative electrodes for rechargeable lithium batteries. J Power Sources 2005 139 314-320. 

Edison cell — A nickel-iron (Ni-Fe) secondary (rechargeable) cell independently developed by Edison in USA and W. Jiinger in Sweden in 1900. The cell (-> battery) is based on the use of nickel oxyhydroxide (NiOOH) at the positive electrode and metallic iron for the negative electrode, and a potassium hydroxide (KOH) solution containing lithium hydroxide (LiOH) is the electrolyte. The Ni-Fe cell is represented as ( Fe/KOH/NiOOH. The charge-discharge reactions for the Edison (Ni-Fe) cell are as follows ... 

There are two main kinds of rechargeable battery based on lithium chemistry the lithium-metal and the lithium-ion battery. In both the positive electrode is a lithium insertion material the negative in the former is lithium metal and in the latter it is a lithium insertion host. The reason for the application in lithium batteries of insertion electrode materials, which are electronic and ionic conductive solid matrixes (inorganic and carbon-based), is that electrochemical insertion reactions are intrinsically simple and highly reversible. 

The first investigation of Li Co02 was carried out by Mizushima et al. in 1980," where the material was suggested as a possible positive electrode for lithium-ion rechargeable batteries. In 1991 Sony Corporation commercialized the first lithium-ion battery in which lithium cobalt oxide was used as the positive electrode and graphite (carbon) as the negative electrode. Since then, LiCo02 has been the most widely used cathode material in commercial hthium-ion batteries and retains its industrial importance as a cathode material. 

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