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Old 04-02-2008
btrayfors btrayfors is offline
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Cam,

Yes, you're right. We did a study of some of the pulsing devices available for "reviving" batteries and for "preventing" sulfation.

Not sure we're gonna publish, although there's a writeup and a magazine has accepted the idea for publication. Basically, we've not too much to say other than we were unable to discern any useful benefit among the devices we tested and the batteries we used, despite trying for over a year.

This is a very murky area. While there are hordes of affectionados and even cult-like followers, some building and testing their own pulsing "desulfating" devices, and you can find lots of testimonials about their incredible performance, we were unable to find such benefit. And, we know of at least one other scientifically-based trial which also could not discern any serious benefits.

We first became suspicious when we began testing the output of the devices themselves, using a spectrum analyzer and other lab devices. We found that they were all different, i.e., the pulse characteristics differed markedly one from the other in terms of frequency, amplitude, power, pattern, timing, etc. Since the supposed mechanism of action was to inject a pulse which would be resonant with the PBSO4 crystals, thereby causing them to break up, we wondered how the very different pulses could have this effect. We were unable to demonstrate that they did.

I suppose our bottom line to the question, "do these really work, or are they just snake oil", is a decided "maybe". We're not saying that pulsing doesn't work or can't work in some situations. But what we are saying is that it hasn't been proven anywhere to our knowledge and we are recommending that a purposeful longitudinal study be done to find out under which circumstances the technology might work. This would have to be financed by some government entity to remove any manufacturer bias; it should be done by a recognized technical lab (Sandia???); and should be given enough time and funds to settle the issue.

Now, that said, the type of pulsing I was talking about above is different. Car manufacturers investigating battery technologies for hybrid cars have found that the most effective way of recharging is via pulse chargers. These are high-amperage, relatively high voltage devices.

The Iota chargers use PWM technology. They use a pretty high voltage spike during the charging cycle, but pulsed in such way that the batteries cannot be damaged through overheating. Note that there is no battery type setting on the Iotas...they can be used with any type battery. I have two of them, one on the boat which maintains my dedicated anchor windlass battery bank in the forward cabin (2 T-105s in series), and one at home which maintains the T-105 battery bank which powers all my radios. In both cases, the Iotas have kept these batteries healthy for several years -- as measured by a sophisticated internal resistance device -- while even top-of-the-line marine chargers like the Victron Multi-plus on my house batteries (6 T-105s) have not done as well.

Sorry for the long post, Cam.

Bill
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