One of the major concerns with traditional NiMh rechargeables is just how weak they are, and just how quickly their longevity declines. With few exceptions, most of these cells can't actually power a dedicated hotshoe flash for more than a few minutes (if at all), and any application that demands a serious amount of power generally asks too much from these pricey tubes. Furthermore, these batteries also have a tendency to go from fully charged to empty faster and faster as time goes on, and while we understand that said phenomenon is simply a harsh reality when dealing with devices such as this, we always felt that the performance decline was unacceptable given the price premium attached to 'em.
Enter PowerGenix, a little known company with a lot of hustle and a pocket full of promises. The company is selling 1.6v AA Nickel Zinc rechargeables at a variety of outlets now, with the MRSP for a 4-pack sitting at $14.99; the special charger (needed for charging NiZn batteries) can be purchased along with four cells for $34.99 (again, that's MSRP). Needless to say, both are available for less if you poke around a bit. We began using these with exceptionally low expectations, and six wedding shoots later, we're now grinning from ear to ear. Our Nikon Speedlight SB-600 chews through standard batteries like a voracious beast, only squeezing out around 200 to 300 shots on a warm, lucky day. The PowerGenix cells, however, allowed us to fire the flash anywhere between 300 and 400 times in all conditions, and even after running them bone dry and juicing them back up for months on end, we've yet to see 'em take a performance hit.
Naturally, these will also keep your wireless keyboard, mouse or remote ticking for a long, long time, but it's their ability to shine even in high-drain applications that really impressed us. The economics of it just make these tough to ignore: a 4-pack of Energizer's 'Ultimate Lithium' AA cells can be had for around $7 to $10, while the 4-pack of PowerGenix batteries cost just a few bucks more (charger notwithstanding). If you're a power user that eats through 8, 12 or more AA cells at every stop, it's a no brainer to make the switch to NiZn. If you find yourself buying batteries around once per year, you're probably better off sticking with your current habits. But hey -- at least there's finally a great solution for those of us who've been procuring more batteries than toilet paper over the past few years.
