Nanocomposite Polymer Electrolyte Doped with Nanosized Li[sub 0.1]Ca[sub 0.9]TiO[sub 3] for Lithium Polymer Batteries

Abstract

A poly͑ethylene oxide͒ ͑PEO͒-based nanocomposite polymer electrolyte ͑NCPE͒ doped with nanosized Li 0.1 Ca 0.9 TiO 3 , a lithium fast ionic conductor, has been developed. The ionic conductivity and lithium ion transference number of PEO 12 -LiClO 4 -Li 0.1 Ca 0.9 TiO 3 NCPE are both enhanced by the addition of nanosized Li 0.1 Ca 0.9 TiO 3 , with a maximum ionic conductivity of 1.02 ϫ 10 −5 S cm −1 at room temperature and a maximum lithium ion transference number of 0.533 at 70°C when the Li 0.1 Ca 0.9 TiO 3 content is 15 wt %. A broad electrochemical stability window suggests that the NCPE is a viable candidate for the electrolyte material in lithium polymer batteries. A solid-state lithium polymer battery has attracted the attention of many researchers because of its features, such as flexibility in the shape of the cell design, leak-proof electrolyte, and high safety. The key component in a solid-state lithium polymer battery is the polymer electrolyte. For a fully dried polymer electrolyte, poly͑ethylene oxide͒ ͑PEO͒ has been considered one of the most favorable lithium conducting matrices. The main drawback of PEO-based polymer electrolytes is the relatively high crystallinity of PEO at room temperature.1 This reduces the ionic conductivity of PEO-based polymer electrolytes to a level that is too low to satisfy the general requirements of batteries or other practical electrochemical devices. To improve the ionic conductivity at ambient temperature, most research efforts have been dedicated to obtaining solid polymer electrolyte films containing a variety of stable amorphous phases; these afford us good flexibility of the polymer chains, which favors ion transport. To date, most of the successful work has been carried out using inorganic materials, such as ceramic and nano-oxides, 2-7 layered clays, [8][9][10] organic-inorganic hybrid materials, 11,12 and microporous molecular sieves [13][14][15] as fillers to enhance the ionic conductivity of the polymer electrolytes. However, none of these inorganic fillers is an ionic conductor that introduces lithium ions into the polymer electrolyte. In an effort to further enhance the ionic conductivity, Wang et al. 16 introduced a lithium fast ionic conductor Li 3−2x ͑Al 1−x Ti x ͒ 2 ͑PO 4 ͒ 3 ͑x = 0.55-1.0͒, produced by a conventional solid-state reaction, into a PEO-based polymer electrolyte. The ionic conductivity of a PEO-LiClO 4 -Li 1.3 Al 0.3 Ti 1.7 ͑PO 4 ͒ 3 film with ethylene oxide ͑EO͒/Li = 8 reached a maximum of 7.985 ϫ 10 −6 S cm −1 at room temperature when the Li 1.3 Al 0.3 Ti 1.7 ͑PO 4 ͒ 3 content was 15 wt %. However, the modal grain size of the Li 1.3 Al 0.3 Ti 1.7 ͑PO 4 ͒ 3 powders is larger than 0.5 m, which may adversely affect the electrochemical properties of the resulting solid composite polymer electrolytes. Nanosized fillers have been chosen as additives in PEO-based composite polymer electrolytes and are effective in enhancing the ionic conductivity, lithium ion transference number, and electrochemical stability. −5 -10 −6 S cm −1 ͒. 16 Thus, t...

Nanosized Flame Retarded HydroxideMagnesium/Poly(ethylene-oxide) Composite Polymer Electrolyte

“…或无机物 [6][7][8][9][10][11][12][13][14][15][16][17] 共混, 以破坏 PEO 分子链排列的 规整性, 获得非晶结构, 提高离子电导率;(2) 通过形 成无规共聚物 [18] 、 嵌段共聚物 [19] 、 梳形共聚物 [20][21][22] 、 超 枝化和星形聚合物 [23][24][25] 以及交联 [26] , 、 TiO 2 [11] 、 MgO [12] 、 Al 2 O 3 [13] 、 铁电材料 BaTiO 3 和 SrTiO 3 [14] 、 LiAlO 2 [15] 、 导 电的碳黑 [16] 和 AlBr 3 [17]…”