Battery heated gloves are ideal for motorcyclists, skiers, fishermen, and snowmobilers, etc. The gloves are made out of different types of materials and generally come with a soft and warm insulation that also pads the gloves. Some models are waterproof and/or windproof. Most of them are also adjustable and come with a small cobalt ontario-ion battery in each glove that heats them up.
It isn't always possible to be near an outlet to keep a charger running. A laptop is supposed to be portable. But a user may still need to be on their computer lithium facts more than just or hours their batteries allow them. That can turn into a real problem if the person can't keep their computer running because its battery just died.
The lithium-ion battery is light years ahead of the earlier batteries and considerably better than the Nickel-cadmium (Ni-Cd) or the nickel-metal hydride (Ni-MH) batteries which are still being used. These batteries are less expensive but the Li-ion batteries are far superior in three ways.
Avoid using replacement that has been on lithium bettery stock for a while. During storage the battery can lose much of its capacity through internal resistance, which damages it and lowers the maximum capacity.
Briefly relating back to overall size... many lithium 18650's will differ ever so slightly in length (measured in millimeters). This is mainly due to an added protection circuit. The circuit helps to prevent the battery from over-discharging, since Li-ion cells can easily become damaged if their power is drained below a particular voltage. The protection circuit also prevents the cell from being over-CHARGED as well. These cells are very sensitive. They must be handled carefully, gently, and as described above, must never run-down too far, or be charged over and above their threshold. They can actually explode if severely mistreated!
Battery chargers for mobile phones are notable in that they come in a wide variety of connector-styles and voltages, most of which are not compatible with other manufactures' phones or even different models of phones from a single manufacturer.