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»  Edan Starts to Deliver Anti-overcharge Lithium-ion Cells

Edan starts to deliver anti-overcharge lithium-ion cells in Q3, 2004. Overcharge has been the key reason of the explosion of lithium-ion battery cells. The anti-overcharge technology can greatly improve the safety of lithium-ion batteries.


Lithium-ion battery cells may explode when they are overcharged to 4.6V or above. The molecular bonds of some materials in the cell start to break near or above 4.6V. The cell starts to produce unexpected gases and increase the air pressure inside the cell. At the same time, lithium atoms also start to accumulate on the surface of negative electrode. Once the high-pressure gases break the metal enclosure of the cell, Oxygen will enter and react with lithium, which usually results in fire or explosion. Although lithium-ion battery packs are usually protected by a protection circuit board to prevent overcharge, there is a chance that the protection module fails. Once it fails to protect the cell, the cell will be overcharged and exploded. So, anti-overcharge formula has long been waited by the battery industry. But for cost and other reasons, it is only seen on cells made by market leaders, such as Sanyo and Sony. And this type of cells are usually sold at much higher price.


Edan’s anti-overcharge technology is realized by a fuse, which permanently breaks the current path when a cell is overcharged. This technology has no side effects on cycle life, capacity, and internal impedance. Edan will use this technology in cells designed for portable DVD, MP3, and bluetooth applications.