Combining the time-tested reliability and power of the internal combustion engine with the low-rev efficiency and emissions-free locomotion of an electric motor, hybrid vehicles have proven extremely popular with the American public.  New hybrids are almost immediately in high demand, and with gas prices continuing to climb upward, the interest seems unlikely to flag anytime soon.

However, there are many downsides to hybrid technology that negatively affect both vehicle performance and the pocketbook of the American consumer.  The weight  of the combined battery and engine makes hybrids heavier than comparable vehicles.  Existing battery chemistry can be very expensive to create, as it can contain a variety of rare metals. Disposal may increase the cost of ownership, too, due to the presence of highly toxic materials.  Plus, popular lithium-ion batteries have a nasty tendency to explode.

But now, PowerGenix, a battery company based in San Diego, has developed an impressive, relatively environmentally friendly solution to the unique problems presented by hybrid-electric vehicles: nickel-zinc batteries.  NiZn, with its 30% increases in capacity and power over existing batteries of  similar size, is ideally suited for high-power, low-drain applications, such as HEVs. The use of a zinc, which is quite cost effective at less than a dollar per pound, offers excellent price savings compared to lithium-ion and metal hydride batteries.  Reduced toxicity increases the ease of disposal, and the more stable battery chemistry eliminates the chances of an unexpected explosion.

NiZn power is not a new technology. Thomas Edison worked with NiZn during his career, and the technology has been used in transportation before, powering a few streetcars in Ireland during the 1930s and '40s. Until recently, however, the Achilles’ heel of NiZn batteries had been their cycle life limitations.

But recent developments in the use of electrolyte additives have created NiZn batteries good through hundreds of cycles, making them a viable alternative to existing technology.  Additionally, PowerGenix’ NiZn cells operate at 1.5v, the same voltage of existing disposable batteries, making them an ideal and longer-lasting replacement for the billions of alkaline batteries in use worldwide.

Realizing the potential of the technology, PowerGenix planned ahead, designing its NiZn batteries to be readily produced using existing infrastructure. “Technology design from the get go was for production on existing nickel metal-hydride and nickel-cadmium lines”, says PowerGenix CEO Dan Squiller. And the move has paid off—through an overseas supplier, PowerGenix will be able to produce some 1.2 million cells each day.

Like any other technology, NiZn batteries are not a magic fix. Existing zinc mining operations do have significant environmental downsides, and nickel, though used in most existing rechargeable batteries, remains a expensive. Still, these issues not withstanding, nickel-zinc batteries represent an exciting new frontier for hybrid vehicle development.