Though most people don’t think of it as such, the oldest and most often used type of rechargeable battery is found in automobiles. The lead-acid batteries that most cars and trucks employ is recharged by the alternator when the vehicle is running. These batteries were once very often sent to landfills when they were no longer able to take a charge.
However, in recent years, regulations regarding the recycling of automotive batteries require nearly all sellers of such batteries to take the old ones back for rework when a new one is sold. This scheme has resulted is a tremendously high rate of recycling – well over 95% in most areas – and is currently being held up as an example of the sort of job people can do when regulations, markets and consumer desire to do the right thing come into play. As a side benefit, the amount of lead that is distributed into the local soil and watersheds is significantly reduced.
In addition to the lead-acid batteries that are found in automobiles, there is a dizzying array of rechargeable battery types to choose from, even within the same battery configuration and size.
By the late ‘aughts, the Li-ion battery is perhaps the most popular type of non-automotive used in consumer electronics in North America. This is primarily due to its user friendly nature, as it has a high weight to charge ratio, little discharge loss and no pesky memory of past charge levels.
Invented in the 1980s, these batteries are able to deliver considerably more power than their Nickel-cadmium counterparts that have been around for over a century. However, they do discharge much faster and have a much shorter life-span.
These are the oldest type of commonly used small batteries and are very sturdy, taking up to several thousand charges. They do, however, deliver a less stable voltage than their more modern counterparts. Also, cadmium is a highly toxic metal.