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Rechargeable Batteries Test

PowerGenix NiZn Rechargeable

PowerGenix NiZn Rechargeable


Charger and 4 AA batteries – $30

4 AA batteries – $15

3.5 Stars

+ High voltage

+ Long battery life

+ Adapter for C and D cells

+ Quick Charge

- Too much voltage for flashlight

- Too big for some uses

Because they’re based on a different chemistry make-up than the other rechargeable cells in this group, PowerGenix NiZn Rechargeable batteries set the pace for long life--but there’s a snag. These cells are slightly thicker and produce so much power that they can burn out a flashlight’s bulb. Clearly, they’re not for all uses.

These batteries use the chemical interaction between nickel and zinc and can store more energy than nickel-metal-hydride, nickel cadmium or lead acid batteries.The batteries come pre-charged and deliver 1.79 volts. That’s 15 percent better than disposable Duracell batteries and 22 percent higher than the three rechargeables reviewed here that use nickel-metal hydride technology.

Rated at 2,500 mili-amp hours of power, the NiZn cells zoomed to the top of the class of long-lasting rechargeable batteries. They ran the CD player for more than 14 hours, three-times longer than the Energizer Rechargeables could. 

On the downside, they burned out bulbs in two flashlights I tried: the Husky light I used for testing, as well as a Mini-MagLite, but worked well in an LED flashlight. The company representative I spoke with said the company plans to add a warning to the packaging.

Plus, the cells measure .01-inch thicker than Duracell disposable batteries, making them a tight fit in some gadgets. The Rayovac cells also suffered from this problem.

During charging the NiZn cells and charger are quick and quiet. The charger holds up to four AA or AAA batteries and it’s impossible to put them in backwards.  You can charge one, two, three or four cells at once, unlike some of the others which require charging in pairs. Unlike the Rayovac charger which doesn’t tell you when it’s done, the NiZn charger’s red light turns green when the cells are ready.

It took 1 hour 24 minutes to juice up a pair of AAs, four times longer than the Energizer’s quick charger. They came out of the charger warm, but much cooler than the Energizer cells. This is much shorter than the 7 hours and 40 minutes that the Rayovac charger required. The NiZn charger uses 4 watts and will cost less than 3 cents a year in electrical costs.

The charger itself weighs 4.3 ounces, and is in between the heavier Energizer and lighter Eneloop device. Like the others, it has a fold open two-prong plug, making it perfect for travel.

Rated at 1,000 charge cycles, the NiZn batteries can outlast most of the other rechargeables, making the $30 investment for a charger and 4 AA cells go down easier. A pack of four extra cells costs $15. They come with a 1 year warranty.

Bonus: if you mail in the product’s packaging and a copy of your receipt, the company will send you a pair of holders to use the rechargeable AA cells in devices that require “C” and “D” cells. Looking for the longest-lasting rechargeable batteries for electronics around? Look no further than PowerGenix’s NiZn cells. Just don’t put them in a flashlight.