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With lithium-ion battery energy density, the output voltage high, long cycle life, environmental pollution, small advantages, such as Xiao Xing digital electronic products has been widely used application, in Diandong automotive, aerospace and other fields are also found widespread application. However, in recent years for mobile phones, digital cameras and notebook computers in the lithium-ion battery explosions have been common assault incidents, the safety of lithium-ion batteries cause for widespread concern. Only in May 2009 took place on several cases and the safety of lithium-ion battery-related incidents, including the original HTC Touch Pro battery burning events, as well as Hewlett-Packard laptop battery recall. HP recall the reasons given by those batteries overheating of the fire and burn hazards of consumers, the battery is said to have occurred at least two accidents, mainly because of battery overheating, rupture cause a fire. Present report safety problems of lithium-ion battery for digital products focused on in a small lithium-ion batteries, and cell phone batteries, notebook batteries, as the capacity higher risk of problems is relatively high; and for transport the large battery or battery power, its security is more prominent, the current security problems have restricted the lithium-ion batteries to large-scale, high-energy direction of the bottleneck. 2 lithium ion batteries because of safety issues 2.1 The safety of the battery system Lithium-ion batteries as a system, its security mainly from thermal runaway under the abuse occurred. Battery system shall be the system of thermal control over the release of the heat generated by the heat accumulation caused by heat, the process temperature increases [1]. Lithium-ion battery thermal runaway occurs, mainly between the electrode and the electrolyte caused by chemical reaction. Electrolyte for the organic solvents commonly used carbonate esters, which have high activity, easy to burn. In the charge state of battery cathode material for the strong oxidizing compounds, while in the charge state of the anode material for the strong reduction of compounds. In abuse cases, such as overcharging, overheating and short circuits, strong oxidizing cathode materials are usually less stable, easy to release oxygen, carbonate reaction with oxygen easily, evolution of considerable heat and gas; heat will further accelerate the decomposition of positive, resulting in more oxygen, to promote more exothermic reaction carried out; the same time reducing negative strong close to the lively nature of lithium, and oxygen burning and ignite immediately contacted the electrolyte, separator, etc. [2, 3]. Lithium-ion battery in the abuse cases, the presence of the internal temperature rise leading to a large number of exothermic reaction occurred too late to release the heat dissipation in the battery and aggravated battery in the accumulation of internal heat release reaction, so a vicious cycle leading to the battery temperature increases out of control process, namely, battery thermal runaway.laptop battery laptop battery Power tools battery Camcorder Battery Digital Camera Battery CANON Camcorder Battery JVC Camcorder Battery PANANSONIC Camcorder Battery SONY Camcorder Battery SHARP Camcorder Battery CANON Digital Camera Battery
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