Mobile technology has re-written the rules. Now, work and play can be wherever and whenever you want. And rechargeable batteries make it all possible. They also save you money and they're better for the environment.

Some say you can save money by switching from disposable to rechargeable batteries. We decided to test the claim.

A lot of people like to listen to music while they work out. So we conducted our test at the gym.

A pack of 4 AA batteries costs about $3. A charger and a pack of rechargeable batteries will set you back about $20.

Average gym users told us they go through a set of batteries about once month. Of course that varies according to how long they listen. But at that rate they'd be spending about $36 a year on
batteries.

Rechargeable batteries would pay for themselves in less than seven months. Manufacturers claim rechargeable batteries can be recharged thousands of times.   

At the end of that long lifespan they will eventually die. When they do they need to be properly recycled.

Recycling programs are pretty easy to find. Most major electronics stores have them in place or can steer you in the right direction.
   
Science and technology magazine says rechargeable batteries have 32 times less impact on the environment.

The cost for recharging a battery is pretty low. It's estimated to be about 2 cents a recharge.