Many people have misconceptions about hybrid car batteries: "You don't want a hybrid 'cause every couple days you've gotta plug them in somewhere to recharge the batteries."

But interestingly enough, many hybrid car owners actually would like the ability to plug in their vehicles at night. This way, they can use that much less gasoline; the gas engine part of the hybrid would now need to run that much less when they made their morning commutes. Now, nothing's free--including household electricity. However, the idea here is that the additional charges on their monthly electric bill would still be far less than the added $3.00+ per each additional gallon of fuel. The 2008 and beyond hybrid electric vehicles are supposedly going to have the capability to plug them in.

Another popular myth is that the batteries only last a couple years at the most. Then you've gotta buy thousands of dollars worth of new batteries. This is far from true:

The standard warranty on hybrid batteries usually runs between 80,000 and 100,000 miles. Great advances in battery technology since 2000 have raised the life expectancy to a respectable level in 2007. Taxi services using hybrid-only cars are springing up everywhere...now THAT should raise the eyebrows of hybrid naysayers. The warranty for battery life may be at 100,000 miles, however, taxi services are seeing 200,000 to 300,000 miles with absolutely no degradation in battery performance. And we're talking several large taxi fleets in New York City!

If the batteries DO need replacing, they will cost between $1700 - $3000, not $10,000+ like many folks say.

But the key to this long battery life lies in "smart charging" where the electronic charging computer will not let the battery get charged above around 60% of capacity, nor let it drop below 40% of its capacity. This allows the new NIMH (Nickel Metal Hydride) batteries to run practically forever.

That being said, battery technology remains the main area for the greatest advances in hybrid car technology yet to come. Lighter batteries that hold longer charges and put out higher power is the dream of every hybrid engineering company. Battery technology is where hybrids stand to gain the most benefit.

The main hope for improving this situation for hybrid cars lies with lithium batteries. These are the same batteries that are currently used to power laptops and cameras. They provide a much more concentrated and therefore smaller way of storing energy as electricity. While lithium batteries are the best option for batteries in hybrids now, they aren't without problems...

The problem with lithium batteries is making them big enough so that they can store enough energy to power hybrid cars without having to revert to the gas engine when driving in town. Lithium batteries are very efficient when manufactured to a certain capacity and size. But if this is increased they are subject to a condition called thermal run off. This can cause larger batteries to overheat and in some instances they can actually catch fire! (You've noticed how hot laptop computer batteries can get.)

The main problem is the cobalt, a metal used in the manufacture of lithium batteries. Many manufacturers have been working on a solution to this problem. The most promising solution seems to be replacing the cobalt with phosphate. This produces a much safer and more reliable battery. There is some power loss as opposed to using cobalt only, but the batteries should still be a long way ahead of conventional lead-acid and NiMH batteries now used in hybrid cars.