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Lithium-Ionen-Technologie

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Lithium-ion technologie

Today´s lithium-ion batteries represent the state of the art in the development of rechargeable batteries. They are not affected by the memory effect and can therefore be charged up at any time without reducing their capacity.
With 90 to 110 Wh/kg, they have the highest energy density in relation to weight and volume in comparison to conventional rechargeable batteries such as NiCd or NiMH. Lithium-ion cells have a voltage of 3.6 V instead of the 1.2 V in NiCd-or NiMh batteries. This is due to the special materials involved. A lithium compound consisting of cobalt-, manganese- or nickel-oxide or of a mixture thereof is used for the cathode electrode. The anode is made of a graphite compound. The insulation between the two electrodes consists of a micro-permeable plastic membrane. A dissolved lithium ion salt in organic solvent is used as electrolyte. For reasons of safety lithium-ion batteries are equipped with a pressure release valve and a particularly pressure-resistant casing.
The charging process must be performed with utmost precision and is therefore controlled by special electronic components. They prevent an excessive current flow, control the charging and discharging characteristics and protect against overheating. (See also: Rechargeable battery, IXO, Cordless power tools)