What Are Li-ion Batteries?

Lithium-ion (Li-ion) batteries are made up of lithium compounds that are more stable than the elemental lithium used in its purest form to make lithium batteries. Unlike lithium batteries, the lithium-ion batteries are rechargeable and can be recharged hundreds of times, while the lithium battery should never be recharged. Lithium-ion batteries are sometimes referred to as the rocking chair battery because the lithium ions (Li+) rock back and forth between the negative and positive electrodes while the cell is being discharged and charged, according to the Battery Chronicle website.

 

Lithium-ion batteries have a higher density than most batteries, allowing them to store more energy for their size. The batteries operate at a higher voltage than other rechargeable batteries, which means one cell can be used instead of multiple nickel-cadmium (NiCd) or nickel-metal hydride (NiMH) cells. Additionally, because lithium-ion batteries hold a charge for a longer period of time, even while not installed in an electronic device, they are more practical than the NiCd and NiMH batteries. Specialty lithium-ion batteries can provide sufficient very high current to power tools. These batteries have rapid recharge capabilities, no memory effect and broad temperature ranges for operating.

 

Lithium-ion batteries are more costly than similar NiCd or NiMH batteries because they are manufactured in smaller quantities and are more complex to make. Sophisticated chargers are also required to safely monitor the recharging process, and each size of the Li-ion battery needs its own charger. The batteries are also fragile and need a protection circuit to maintain voltage and assure safe operation, according to the Battery University website.

 

Lithium-ion batteries are not available in standard battery sizes like AA, C or D. This is a safety feature that can avoid a potential fire. Operating at a much higher voltage -- 3.7 volts per cell -- accidentally putting a lithium-ion battery into an NiMH or NiCd charger not designed for a lithium-on battery can cause the battery to ignite, according to Green Batteries.

 

Lithium-ion batteries are able to maintain a charge for many months. The battery should be stored when it is fully or at least partially charged. Storing the lithium-ion battery with a very low charge for many months can allow the voltage to drop below the built-in safety mechanism that allows it to be recharged. For long storage periods it is best to recharge the battery after a few months. According to Green Batteries, for best results the battery should be used every few months and left with a partial or full charge.

 

As a rechargeable battery, lithium-ion batteries are recyclable and should therefor be recycled. Lithium-ion batteries should never be incinerated because they may explode. Businesses that sell the batteries will also take them back for recycling, according to Green Batteries.