Lithium Ion (Li-ion) - 3.6 volts per cell
| Lithium Ion (Li-ion) Batteries | ||||||||
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Pioneering work for the lithium battery began in 1912 by G. N. Lewis but it was not until the early 1970's that the first non-rechargeable lithium batteries became commercially available. Now on the market and growing in use for low amperage appliances like mobile phones, laptop computers and video cameras where size is important (each cell has a large capacity, size-wise, and is three times the voltage of the other battery chemistries). This battery is more expensive as each one contains a control circuit to limit the voltage peak during charging. It cannot be charged on a NiCd or NiMH charger. It has a low charge/discharge life of 300 to 500 cycles. The energy density of the Li-ion is at least twice that of the NiCd and its load current rating is reasonably high. In fact, the Li-ion behaves similarly to the NiCd in terms of discharge characteristics. In addition, the Li-ion has a relatively low self-discharge. The Li-ion battery has no "memory" problems and can be charged at any time. The high cost of production is expected to drop with volume manufacturing and with the substitution of the current cobalt element of the chemistry. There are two basic Li-ion types that have emerged: the coke version by Sony and the graphite version that has now been adapted by most other manufacturers. The new graphite electrode provides a flatter discharge voltage curve than the coke electrode and offers a sharp knee bend, followed by a rapid voltage drop before the discharge cut off point. Li-ion batteries have a very high energy density. Exercise precaution when handling and testing. Do not short circuit, overcharge, crush, mutilate, nail penetrate, apply reverse polarity, expose to high temperature or disassemble. High case temperature resulting from abuse of the cell could cause physical injury. Each battery should be treated with care as it is very volatile, highly inflammable and difficult to extinguish when alight - like magnesium. It is not regarded as hazardous to the environment. The technical literature suggests that it has a life of two years from "date of manufacture"! | ||||||||
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