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A lithium-ion battery (sometimes Li-ion battery or LIB) is a member of a family of rechargeable battery types in which lithium ions move from the negative electrode to the positive electrode during discharge and back when charging. Li-ion batteries use an intercalated lithium compound as one electrode material, compared to the metallic lithium used in a non-rechargeable lithium battery. The electrolyte, which allows for ionic movement, and the two electrodes are the constituent components of a lithium-ion battery cell. Lithium-ion batteries are common in consumer electronics. They are one of the most popular types of rechargeable batteries for portable electronics, with a high energy density, small memory effect,〔(【引用サイトリンク】title=Memory effect now also found in lithium-ion batteries )〕 and only a slow loss of charge when not in use. Beyond consumer electronics, LIBs are also growing in popularity for military, battery electric vehicle and aerospace applications. For example, lithium-ion batteries are becoming a common replacement for the lead acid batteries that have been used historically for golf carts and utility vehicles. Instead of heavy lead plates and acid electrolyte, the trend is to use lightweight lithium-ion battery packs that can provide the same voltage as lead-acid batteries, so no modification to the vehicle's drive system is required. Chemistry, performance, cost and safety characteristics vary across LIB types. Handheld electronics mostly use LIBs based on lithium cobalt oxide (), which offers high energy density, but presents safety risks, especially when damaged. Lithium iron phosphate (LiFePO4), lithium manganese oxide (LMO) and lithium nickel manganese cobalt oxide (NMC) offer lower energy density, but longer lives and inherent safety. Such batteries are widely used for electric tools, medical equipment and other roles. NMC in particular is a leading contender for automotive applications. Lithium nickel cobalt aluminum oxide (NCA) and lithium titanate (LTO) are specialty designs aimed at particular niche roles. The new lithium sulphur batteries promise the highest performance to weight ratio. Lithium-ion batteries can be dangerous under some conditions and can pose a safety hazard since they contain, unlike other rechargeable batteries, a flammable electrolyte and are also kept pressurized. Because of this the testing standards for these batteries are more stringent than those for acid-electrolyte batteries, requiring both a broader range of test conditions and additional battery-specific tests.〔Millsaps, C. (10 July 2012). (Second Edition of IEC 62133: The Standard for Secondary Cells and Batteries Containing Alkaline or Other Non-Acid Electrolytes is in its Final Review Cycle ). Retrieved from Battery Power Online (10 January 2014)〕 This is in response to reported accidents and failures, and there have been battery-related recalls by some companies. ==Terminology== Although the word "battery" is a common term to describe an electrochemical storage system, international industry standards differentiate between a "cell" and a "battery".〔 A "cell" is a basic electrochemical unit that contains the basic components, such as electrodes, separator, and electrolyte. In the case of lithium-ion cells, this is the single cylindrical, prismatic or pouch unit, that provides an average potential difference at its terminals of 3.7 V for and 3.3 V for . A "battery" or "battery pack" is a collection of cells or cell assemblies which are ready for use, as it contains an appropriate housing, electrical interconnections, and possibly electronics to control and protect the cells from failure.〔 In this regard, the simplest "battery" is a single cell with perhaps a small electronic circuit for protection. In many cases, distinguishing between "cell" and "battery" is not important. However, this should be done when dealing with specific applications, for example, battery electric vehicles, where "battery" may indicate a high voltage system of 400 V, and not a single cell. The term "module" is often used as an intermediate topology, with the understanding that a battery pack is made of modules, and modules are composed of individual cells.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Lithium-ion battery」の詳細全文を読む スポンサード リンク
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