Polymer Lithium ion Battery have replaced nickel-cadmium (NiCd) batteries, which were first used to power laptops and nickel-metal hydride batteries (NiMH), which replaced NiCd laptop battery technology. They dominate the market today, notebook batteries, because they are much lighter than other types of laptop batteries, they retain a charge longer than other technologies because they do not suffer from the memory effect phenomenon. A typical lithium ion battery has twice the energy density of conventional nickel-cadmium batteries. In addition, lithium-ion batteries have a cell voltage of 3.6 volts to 1.2 volts per cell nickel-cadmium batteries.

However, the disadvantages associated with lithium-ion batteries include: the possibility that the battery could catch fire under adverse conditions, they are more sensitive to high temperature environments than other battery technologies in their ability to retain charge , they may fail when they are fully discharged, the battery chemistry and inherit degraded with age, in contrast to the strong correlation between battery failures and cycles of charge / discharge higher chemical batteries. Lithium-ion batteries also require a computer that will be included in the circuit to protect the battery to monitor the battery and to ensure safe levels of voltage and current, and to ensure that the temperature of the battery is in the operating range .

Cylindrical lithium-ion batteries are generally tubular form and manner standard alkaline batteries. Several cells are enclosed in a plastic box and individual cells are connected in such a way as to ensure proper output voltage and maximum storage capacity (rated in milliamp hours). Prismatic lithium-ion batteries are also available, but they are much smaller and are usually used in devices such as mobile phones, where weight and space are the highest priority.

There are several things that affect the life of lithium-ion laptop batteries. NI-CD Rechargeable Battery degradation is accelerated by heat, so that the battery in a cool place to prolong his life. Manufacturers generally recommend a storage temperature of 60 ° F for long-term storage of lithium-ion batteries. These batteries, as I mentioned earlier, we do not keep the memory of the partial discharge cycles, so it requires a full cycle discharge for the implementation of the budget. In fact, a partial cycle will help to extend battery life. Lithium-ion batteries have a limited life as the old battery technology, but it is relatively independent of their charge cycle, especially related to their age. A typical battery will last 2 to 3 years. This is true even if the battery is not used, it is important not to buy a replacement laptop battery until it is ready to be put into operation.