41.  It turns itself on at dusk and off at dawn, and comes with rechargeable batteries and lamps the company says never need replacing.

42.  Laptops also have this kind of battery, which is separate from the rechargeable battery that is the main power source.

43.  Most desktop computers today do not use rechargeable batteries.

44.  Motorola says it still faces the technical challenge of making the fuel cells less expensive than rechargeable batteries.

45.  Now there is the prospect of a promising new type of rechargeable battery that is not only long lasting but also reasonably cheap to make.

46.  One is a new variation on lithium ion batteries, the most sophisticated and expensive of rechargeable batteries.

47.  Photovoltaic cells on the top of the lights convert solar energy to electrical energy, which is then stored in rechargeable batteries in the fixture itself.

48.  Powered by rechargeable batteries, they automatically sense irregular heart rhythm, determine if a shock is warranted and signal the operator to fire a charge.

49.  Prior to the Renewal battery, all rechargeable batteries were made of nickel cadmium, which can harm the environment if not recycled properly.

50.  Rechargeable batteries are like James Dean.