Lithium polymer-salt

To improve the lithium transference number, a typical approach has been the preparation of a polymer/salt hybrid,8 17 in which an ionic group is immobilized in... 

As described in previous sections (Sections VI and VII), macromolecular design of polymer/salt hybrids with a highly dissociable lithium borate unit proved to be a valuable approach for single-ion conductive polymers. To further improve the degree of lithium salt dissociation, we have designed a polymer/salt hybrid bearing the boron-stabilized imidoanion (BSI)38 (Fig. 10). 

Lithium oxide(s), 15 134, 141 Lithium perchlorate, 3 417 15 141-142 dessicant, 3 360 in lithium cells, 3 459 Lithium peroxide, 15 142 18 393 Lithium phosphate, 15 142 Lithium-polymer cells, 3 551 in development, 3 43 It Lithium primary cells, 3 459-466 Lithium production, 9 640 Lithium products, sales of, 15 121 Lithium salts, 15 135-136, 142 Lithium secondary cells, 3 549-551 ambient temperature, 3 541-549 economic aspects, 3 551-552 high temperature, 3 549-551 Lithium silicate glass-ceramics, 12 631-632... 

The potential use of polymeric ion-exchange membranes in the next generation single-ion secondary lithium polymer batteries was shown by Sachan et al 84,85 Conductivities exceeding 10 S/cm with transference numbers of unity were achieved for Nafion converted to the Li+ salt form. 

Lithium polymer electrolytes formed by dissolving a lithium salt LiX (where X is preferably a large soft anion) in poly(ethylene oxide) PEO can find useful application as separators in lithium rechargeable polymer batteries.Thin films must be used due to the relatively high ionic resistivity of these polymers. For example, the lithium-ion conductivity of PEO—Li salt complexes at 100 °C is still only about Viooth the conductivity of a typical aqueous solution. 

Lithium polymer batteries are similar in principle to the lithium batteries described above but the electrolyte is a polymer. The advantage of these batteries is the absence of liquid in the cell and so the batteries do not leak. The polymer electrolyte is a polymer-alkali metal salt complex. The best known such electrolytes are complexes of poly (ethylene) oxide (PEO). 

Molecular salts of type 65 have also been prepared recently by the reaction of a secondary amine with the linear isomer of hexafluoropropane sultone as depicted in Scheme 18 <2003MI1961>. These lithium polymers exhibit high electrochemical stability and cationic conductivity and therefore are ideally suited for lithium polymer batteries. 

The composite cathode usually consists of an inert conducting material, the polymer/salt electrolyte, and the solid active insertion particles. The key requirements for a material to be successfully used as a cathode in a rechargeable lithium battery are as follows ... 

Films of lithium triflate salt of [NP(0CH2CH20CH2CH20CH3) (MEEP) can be photochemically cross-linked. This inhibits slow loss of electrolyte from the cell. similar results are obtained from [NP[ (0CH2CH20)7R]2] (R=Me, CH2CH=CH2). °° The polymer electrolyte, MEEP/poly(propylene oxide), combined with several lithium salts has been employed as an electrolyte and conductivities have been... 

Electrodes and cell components must be thin to minimise the internal resistance of the batteries the total cell can be less than 0.2 mm thick. Figure 12.11 shows the construction of a multi-layer film, rechargeable lithium polymer battery, using a solid polymer electrolyte. A thin lithium metal foil acts as an anode. The electrolyte is polyethylene oxide containing a lithium salt, and the cathode is a composite of the electrolyte and a... 

Pitawala et al., (2007) studied the combined effect of both plasticizer and nano-ceramic filler on the thermal behavior and conductivity of (PEO)g-lithium trifiuoromethanesulphonate (LiCFjSOj or LiTf) composite polymer electrolyte. The formula (PE0)gLiCFjS03 denotes the chemical composition of the polymer-salt complex in which 9 is the molar ratio of (ethylene oxide (EOl/LiCF SOj). According to their work, addition of 15 wt% Aip lowered the and T of (PEO)gLiTf from 58 °C and °Cto 51 °C and -50 °C, respectively and the con-... 

Historically, the first types of lithium polymer electrolytes to be considered for battery applications were those formed by blending high molecular weight poly(ethylene oxide) (PEO), with a lithium salt LiX, where X is preferably a large anion [9-12], Various books and extensive review articles have been published on these polymer electrolytes [5, 13-16] and thus only their essential properties will be briefly recalled. 

Lithium-polymer (e.g., Li-V6013) Polymer electrolyte Polyethylene oxide with Uthium salt... 

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