Lithium-ion battery packs and cells come in all shapes and sizes, but they're all similar. Check out what the packs and cells look like on the inside.

Lithium-ion Battery Safety Concerns

Remember when laptops were bursting into flame in 2006? It was the lithium-ion battery.

Random explosions from overheating weren't a widespread problem, but nevertheless, lithium-ion battery manufacturer Sony, which came out with the first commercialized Li-ion battery in 1991, had to recall more than 6 million computers because of it [source: Lamb].

Lithium-ion battery packs and cells come in all shapes and sizes, but they're all similar. Check out what the packs and cells look like on the inside.

In the couple of years since then, the Li-ion battery hasn't completely recovered its reputation for safety. Now you can see why putting it inside of a car makes some people a little antsy.

Why is there a chance for explosion? Li-ion batteries work by separating its positive and negative sides by a thin layer, called an electrolyte. The electrolyte is perforated to allow the lithium ions to pass through from one side of the chamber to the other, thus generating a current. Tiny bits of metal that result from the manufacturing process can potentially get stuck in those perforations, preventing the ions from freely flowing. Pressure and heat can then build up, causing an explosion. Also, allowing the ions to move too quickly can lead to overheating as well.

So how does the all-electric Tesla Roadster manage to pack 6,831 Li-ion batteries under its hood without risking a major blow-up? The Tesla's energy storage system that propels the car is equipped with a cooling system, which ensures the batteries don't overheat. It also regulates the speed of the flow of ions to keep them from re-charging or draining too quickly.

Since car companies and scientists realize the broad potential of Li-ion batteries, they have poured time and money into finding ways to reduce any safety hazards. For instance, nanotechnology, the study of atoms and nanostructures, may be able to prevent those dangerous explosions. New nanomaterials, such as nanophosphate, aren't prone to shorting out like graphite, the traditional Li-ion electrolyte [source: Peter].

And speaking of time and money, before Li-ion batteries make their grand entrance into the consumer automotive world, they need to be cheaper and longer-lasting. Learn why and how on the next page.