Green Batteries

New on the market are the nickel metal hydride, batteries now powering up man a laptop computer. Referred to as "Ni-MH' batteries, the hydrides are truly green power sources. These batteries, now available in AA and C sizes, these hold a greater charge than ni-cads, are about as powerful, and can be recharged in the same chargers - and they do it all without the toxic cadmium. The manufacturer, Harding Energy Systems, says that the five-metal alloy they use to substitute for the cadmium is non-toxic. But there's still the matter of nickel, another toxic heavy metal that can contaminate groundwater while in a landfill.

That's where Rayovac's new "Renewal" batteries - the first rechargeable alkalines - come in. These inexpensive batteries eliminate the problem of both nickel and cadmium in landfills. Alkaline batteries are stronger - they last longer and offer more power for bigger things than ni-cads - and the new Renewals hold their charge three times longer than other rechargeables, according to the manufacturer. "Renewals, as do all alkaline batteries, offer a steadier, more consistent power source than ni-cads," say Rayovac's John Daggatt. "That has allowed us to make C- and D-sized rechargeables that can power portable stereos, flashlights and virtually any consumer product. And with no mercury, when a Renewal finally does burn out it can be safely landfilled," he adds. In fact, the state of Minnesota, which prohibits the landfilling of rechargeable batteries, has granted a special exemption for Renewals. "We feel the amount of mercury in Rayovac's product does not pose any significant threat to groundwater," says Charles Williams, commissioner of Minnesota's Pollution Control Agency. But one drawback, says EDF's Denison, is that "Renewals won't work in situations where bursts of energy are needed - as in the flash of a camera. So for now, they won't be replacing ni-cads altogether."

Other industry innovations are in the works as well. Lithium batteries are smaller than other rechargeables, hold their charge longer and can be recharged about 1,000 times. Ni-cads and nickel metal hydrides can be recharged as often, but the lithium batteries are more powerful.

Battery makers are all charged up over the future of batteries. Duracell, Eveready and Rayovac, titans in the battery field, are revolutionizing how we power up everything from Walkmans to laptop computers. "Better rechargeables and new alkaline [traditional] batteries with virtually no mercury will save landfill space and address environmental concerns,' predicts Duracell's James Donahue. But environmentalists are not quite as electrified over the tiny power sources, considering that, in many areas of the country, there are still no effective disposal programs for either single-use or rechargeable batteries. The numbers can be staggering: Americans go through 2.5 billion batteries per year, most of which wind up in local landfills. That boils down to about two pounds of batteries per household per year. And although batteries make up less than half of one percent of U.S. waste by weight, leaching and decomposing batteries contribute to more than 50 percent of the mercury and cadmium in landfills, according to a survey by the San Francisco Recycling Program. Such toxic heavy metals can contaminate groundwater, posing a risk to the communities served by the water source. Unfortunately, the traditional alkaline batteries, which account for over 90 percent of household batteries used today, cannot, be recharged. And while the amount of mercury they contain has decreased 71 percent since 1981, a year's production still makes use of about 170 tons of the toxic substance. And, despite manufactuters' assurances to the contrary, disposal even of the newer mercury-reduced alkaline batteries is still a big problem. Says Judith Kornberg, of the New York City-based Environmental Action Coalition (EAC), "If their outer casings corrode, they could leak what little mercury they have." Mercury and silver oxide batteries - those tiny button batteries used in watches - are likewise not rechargeable, creating further disposal problems. expensive than more common forms.