Powergenix 1.6-Volt Nickel-Zinc AA Rechargeable

I long ago stopped reading Popular Science because it was obvious that most articles were written by people who had no understanding of whatever they wrote about. This blurb is an excellent example.

The "juice" put out by a battery is rated in mAh (milliampere-hours), not volts. These cells' mAh capacity is not stated, neither here nor on the PowerGenix site, suggesting that it's nothing to write home about.

As to the voltage... Most (not all) battery-opearted equipment is designed to work "acceptably" at 1V/cell. (This is a leftover from the days of carbon-zinc cells, which declined pretty quickly from their nominal 1.5 volts.) Nicad and NiMH cells have a fairly constant voltage of 1.2 to 1.25 volts, which is fine for almost any equipment. The voltage does not matter as much as the ability to deliver current at a low source impedance, which both Nicad and NiMH cells can do.

As for "water-based" electrolytes... Most electrolytes are water-based. Your car's battery uses a water-based solution of sulphuric acid.

These cells might very well represent a major breakthrough. But you'd never know it reading about them in Popular Science.

You can download spec sheets at the powergeix website (under "Technology").

For the AA cell type, it says:
1500 mAh typical, 1350 mAh minimum

Since most articles have URLs with them where one can get additional info, being short on information is no biggie.
The batteries are shown as having 2,500 mWh, which when calculated at the 1.6V comes out to 1,562.5 mAh. With the higher voltage it actually makes sense to show the wattage rather than the amperage, as the overall power available is of prime importance.

I found the information interesting enough to check out Powergenix's website and found a review that stated that tests allowed them to get 300 to 400 flash pictures per charge, whereas regular AA NiMH batteries gave at most about 200.
Going to Amazon from there, I picked up a combo of 4 AAs and a charger for about $23.00 delivered price.
Even though PopSci sometimes screws up (and I haven't found any magazine that doesn't), I find most of the info they supply good enough to determine whether I want to check things out further on the web.
Importantly, they supply information on upcoming technologies that otherwise might stay below my radar.

While it would have been nice to have that info included in the article, crimue is right, the info is there, and 1350 mAh isn't half bad.

IddiKlu is right about 1.6 V cells having proportionally more power than a 1.2 V cell with the same charge (charge in the sense of Coulombs, measured in mAh). However, many devices will waste the extra voltage as heat because they have internal voltage regulators that cut the voltage down to a specific level or current mirrors to ensure the current draw is correct. For instance, the luminosity of an LED flashlight depends only on the current going through the LED and any excess voltage is wasted in the resistor or transistor regulating the current. Many electronics also use integrated circuits who draw a specific amount of current to operate, with the current often increasing with higher voltage. 1.2 V cells might last longer than 1.6 V cells for this reason.

charvak and IddiKlu both have good points. Note however that it isn't voltage alone that determines how much power you can get out of the cell. The voltage x mAh is a measure of energy, not power. The amount of power you can get out of the cell is limited by the cell's internal resistance and its open circuit voltage. These cells have a high open circuit voltage and claim to have a low internal resistance. Both are good for supplying a lot of power. Although some devices waste any extra voltage, these days, most electronic devices do not. Most modern electronic devices, such as digital cameras and flashes, use switching power supplies that take full advantage of the extra voltage provided by these cells. In fact, any white LED flashlight that runs on fewer than 3 cells must be using a switching power supply because the operating voltage of a white LED if more than 3 volts. On the other hand, if you use these in are regular incandecent flashlights they'll shine brighter and whiter than when using NiMH but you will probably burn out the bulbs a lot faster because these have a voltage that is actually higher than a normal battery and filament life is a very strong function of voltage.

I do wonder just how good these cells are though because their specs aren't very specific. For example, I'd like to see a graph on how quickly they self discharge and, are they really free of any memory effect? Why don't they make them in the AAA size? I bought a set to try them out and they have worked well so far. They are in a few devices that quit after a very short time with NiMH cells because they require more than 1.2V per cell to operate. If these are great, they have done a poor job marketing them.