pulse tech for batteries

[defever]

anyone have experience w/ puls chargers (or whatever they call them) for keeping the batteries sulphate free??

[knottybuoyz]

I looked into them awhile back to try to rehab some ailing batteries. Plenty of them for sale on e-Bay. Kinda sounds like snakeoil to me. (IMHO not based on any first hand experience).

[Beausoleil]

It would be nice to see the output of a pulser on an oscilloscope, and compare that to a pulse-width-modulated battery charger like an Iota DLS.

Chargers like the Iota, according to Rick M, use PWM to "supposedly" help keep the internal temp of the batteries lower than they would otherwise rise to if charged with a relatively constant current. I guess that's to avoid having to implement costly/complicated temperature sensing (another thing to break on a boat, right?) And they periodically go into an equalization mode (15+ V at about 3A or so) to equalize cell voltage and for the resultant gassing to basically "mix" up the electrolyte so that the sulfuric acid levels are uniform throughout each cell. It's also supposed to help free any lead sulfate crystals (PbSO4) which accumulate on the cell's plates.

I'd guess that the formation of hydrogen gas bubbles occurs not only in the free electrolyte solution, but also between the sulfate crystals and the lead plates, gradually "flaking" them off.

The pulsers, on the other hand, basically generate a high frequency signal which is supposed to break the chemical bonds of the lead sulfate crystals, essentially separating the lead ions (Pb) from the sulfate/sulphuric acid (H2SO4). Like knotty says, sounds like voodoo... I suspect what it does is actually break the larger crystals into smaller ones, so that the regular charging process has a better chance to convert the all the lead sulfate and water back to lead oxide, lead and sulphuric acid:

2PbSO4 + H2O → PbO2 + Pb + 2H2SO4

(The above chemical process from Bill Darden's excellent battery faq.)

Disclaimer: It's been about 27 years or so since I took Chemistry 101/102... So guys - try to rip the above to shreds. Please! That's how the scientific process works! No ID vs. FSM here - just stuff to make boats work!

[Roy M]

I have been installing Pulse tech products in my customer's boats for many years. In my own boat, the last set of batteries lasted 15 years. My neighbors and customers swear by them. I learned of them from a fellow yacht club member, a retired electronics teacher, who became a distributor for them. I disbelieved (forgive me), but learned the error of my ways.

I went to the website and learned about the government research. I have had a fair bit of chemistry and physics, as well as electronics training. I learned that this all evolved from NASA research for the Moon project. Remember Velcro and similar products? Same source of erroneous mumbo-jumbo. Then, the military discovered the product. Made getting them difficult because much of the product was sent off overseas. They are required equipment on combat armored vehicles. Also, the Air Force uses them on emergency runway equipment. Oh yeah, and Scripps Institute of Oceanography, fire departments, police departments, taxi and crosscountry trucking companies, etc., etc. Obviously misguided folks who love to spend money in irresponsible ways.

The chemistry/physics is equally absurd. They claim that a sulfuric acid/lead battery works by the sulfate ions, in solution in the battery electrolyte, offer up an electron whenever one is needed by your electric light bulb. The sulfate ion, now lacking a negative charge, crashes into the lead plates and bonds itself, followed by others, as the battery gives up its supply of available electrons. The poor electrolyte solution becomes depleted of sulfates, making the specific gravity (the density) of the liquid drop as the battery depletes in available charge.

They then claim that the charging system (pick any card: alternator, solar, wind, gingerbread crumbs) reverses the process, but with a catch. Since the charging systems are regulated, a statistically small amount of sufates remain on the battery because they require a weensy bit more energy to sling the recalcitrant electron into that outer valence ring (deep physics here, sorry) than the regulated stream provides. Modern chargers have overcome that problem, though with a twist. You push a secret button and the charger pumps 16 volts into the battery, enough to scare the bejesezus out of the sulfate ion and hurry it home into the electrolyte solution. Problem is, it also heats up the battery plates something fierce. Put your hand on the side of a battery undergoing the "equalization" cycle and you will know what I mean - it gets really hot! That leads to plates shedding lead to the bottom of the battery case, to eventually stack up and short out the plate - hence, dead battery. It also warps the plates, also causing similar termination.

Pulse-Techs (and now, other brands) achieve the desired relocation of sulfates in a more gentle, user-friendly way. Taking electrical power from the battery, itself, they generate a pulse of energy, at one-quarter the frequency of the sulfate-lead bond. The electron makes it over the quantum hump, the sulfate ion is released from its bond and floats back into the solution of the electrolyte. It is fulfilled and happy to have been of service to mankind. Well, maybe I'm going over the top and anthropomorphising. Blame it on the prosylatizing I probably absorbed over the years. At any rate, the specific gravity magically increases.

When I first started testing these systems, I took old, discarded batteries at the dumpster of my yacht club. There is a never-ending supply of them. I used a battery capacity tester, known to those of us in the mysterious trade as a twelve volt toaster oven. The batteries that dropped to zero volts were discarded as shorted out. The ones that wouldn't hold a charge, but still showed a few volts after a load was placed on them, were listed as viable test candidates. After the capacity test, I did a specific gravity test to confirm the lack of sulfates, since they are the only missing compounds that disappear. Then, I placed Pulse-techs (provided by my friend) on the subject batteries and left them alone (with water added, of course) for a month or more. Then I gave the batteries an overnight slow charge. The next morning I tested with the battery hydrometer to find specific gravities of 1270 and GREATER. What a mystery! It must have been the gingerbread crumbs that I sprinkled in concentric cirles, counter clockwise, three times! The battery capacity tester was equally mysterious, the test needle dropped slightly after ten seconds of load. Clearly something weird was going on here. The maintenance workers at the yacht club quickly removed the dangerous batteries to Tijuana, an hour south of us, to get rid of the evidence. They keep clamoring for more.

Beware of these products. The marine stores may be offering them, in small amounts, but it's only because they want you to be happy with their responsiveness to popular demand. It surely isn't because batteries comprise a high level of their inventory and sales. You have been warned, I am not to be trusted in this matter, as I am seriously warped by my association with these products.

[btrayfors]

In a controlled test of several of these "pulsers" over a period of nearly two years, in association with two well-known and respected colleagues (and gurus in the boating industry), we were unable to prove any positive effect of these devices. We were using sophisticated instruments.

Further, at the beginning of the testing we examined the outputs from a number of these devices using a spectrum analyzer. They were all DIFFERENT, i.e., the pulsing differed in amplitude, frequency, duration, waveform, etc. Sort of raises the question, "how can they work if they're all different...very different?".

We know of some testing of these devices by a well-known and serious national testing laboratory. They, as we, were unable to prove any beneficial effects.

Note that these pulsers are NOT the same as the PWM used in some battery chargers (e.g., Iota/IQ4 series). We have reason to believe that pulsing in serious battery chargers not only is effective but is the preferred method of charging lead-acid batteries (including flooded, AGM, and gel).

Snake oil? Maybe. But an entire cult has grown up around the little pulsing devices, and you're gonna find legions of people with great stories who claim miraculous results. Pretty much like the divining rods used for finding water in the desert :-)

BTW, in our tests ONE cycle of battery equalization was more effective in restoring some battery capacity than was six to nine months treatment with the little pulsers!

Bill

[Roy M]

That sounds like it beat the bejeezus out of the guv'ment studies. Good grief! All that money down the drain. And can you imagine the embarassment of those fools who actually imagined the extended battery life? What fools we mortals be.

[S/V Illusion]

I've read argumetns on both sides of this techology, all written but so-called experts, if only in their own mind, including practical testing also done by supposedly knowledgeable people and come to the inescapable conclusion that some types may work and some don't, some batteries are able to be rejuvinated to some extent and others not, and that upon request for data to support their conclusions, I am alsways met with silence.

The internet is probably not the best place to obtain reliable opinions as many are given it seems for no other reason than to sound authoritative or disguise an otherwise obvious attempt to sell you something.

I would suggest anyone who is actually interested to send me a PM as I don't feel comfortable broadcasting the name.email.phone number of someone at Woods Hole with whom you can speak and actually see the results of their testing which might surprise the experts!

[Roy M]

Okay, I know how difficult new tech can be. Lead acid batteries have been around since great grandpa's day, and only last a couple years before they sulfate out. But look at one website reference Pulsetech - ReNew-IT Pulse Technology

Look at the section on "Who's using Pulse technology". Then make a more informed decision.

[knottybuoyz]

Originally Posted by S/V Illusion

I would suggest anyone who is actually interested to send me a PM as I don't feel comfortable broadcasting the name.email.phone number of someone at Woods Hole with whom you can speak and actually see the results of their testing which might surprise the experts!

I think we've all been bitten by the promise of the next wonder technology that's going to make our lives so much better. I've got a basement full of gizmo's and gadgets that failed to live up to their marketing buzz.

Cruisers Forum has created a Vendor forum for the purpose of makers/sellers to showcase their products and answer all the questions posed by boaters. Would it be possible for you to refer this person to our Vendor forum and ask them to join up and provide us with some technical info on their product? We would certainly appreciate it.

[S/V Illusion]

Originally Posted by knottybuoyz

I think we've all been bitten by the promise of the next wonder technology that's going to make our lives so much better. I've got a basement full of gizmo's and gadgets that failed to live up to their marketing buzz.

Cruisers Forum has created a Vendor forum for the purpose of makers/sellers to showcase their products and answer all the questions posed by boaters. Would it be possible for you to refer this person to our Vendor forum and ask them to join up and provide us with some technical info on their product? We would certainly appreciate it.

He isn't a vendor so not sure this would be appropriate. It is interesting that no one (else) has indicated interest - maybe their minds are already made up??
Regardless, I too am always skeptical of something which I don't fully understand but have learned not to be as dismissive as some.

[knottybuoyz]

Originally Posted by S/V Illusion

Regardless, I too am always skeptical of something which I don't fully understand but have learned not to be as dismissive as some.

Me too! Hence the invite.

[Roy M]

Sorry guys, I'm not a vendor. I'm a customer, a satisfied customer. Probably over the top for some, hence the prosalytizing. Anyone has the right to offer observations. Only the reader can make their own judgement. I have noticed, over the years, that there are early adopters to new, unfamiliar technology, and there are those who resist foreign ideas. The test of time weeds things out. In the meantime, I and my ilk are spending our disposable income on synthetic rigging, prop coatings that resist marine growth, and forward scanning sonar. Others prefer to stand by their familiar galvinized wire, home brew antifouling, and leadlines. Different folks, different strokes. This forum has introduced me to a number of new and exciting products which I can explore and consider. I simply offered the same in return. No need to get threatened, is there?

[hellosailor]

Roy?
"Made getting them difficult because much of the product was sent off overseas. They are required equipment on combat armored vehicles."

There's no difficulty in buying pulse chargers, no shortage of them on the market, and they've been on the market for a LONG TIME without anyone generating conclusive proof in any independent testing labs.

Combat vehicles spend very little time plugged into wall sockets, they're usually out blowing things up in the field. And they usually need depot service way before the batteries would give out.

If you could provide any reference to any military spec that REQUIRED the use of pulse chargers, it would really go a long way toward convincing some of us skeptics. But the only time I've seen "milspec" references to devices like this, was the famous milspec for a magnetic fuel filter. Turned out to be a spec that said "When bolted to a bulkhead, the device must remain in place and not come apart during combat maneuvers". And, since the USCG and USN are require to test any item submitted to them for the milspec testing--the devices were indeed "used on" military vessels. Pretty much as paperweights, but on military vessels.

So you may understand, claims are nice, but if you could site any sources, I'd really love to believe someone had found a better way to charge batteries. Just haven't seen it yet.

If 1/3 of all the customers for these things were satisfied with them--that would still be a placebo rate, not proof they worked.

[btrayfors]

Careful with usage....we're not talking about pulse chargers here, but about little devices which produce a pulse and are designed to remove PbSO4 crystals from the plates of lead-acid batteries.

While some models are combined with (low amperage) chargers, most are NOT designed to charge your batteries.

There is good evidence that pulse chargers work very well; by contrast there is, IMHO, no scientific evidence to support the notion that these little pulsing devices ("desulfators") really do anything useful.

In the one scientific test I know of (but, unfortunately, cannot cite due to a NDA), the testing laboratory was unable to prove any beneficial result. This is also what we found, in a limited "semi-scientific" test over a 1.5+ year period.

Based on our experience with more than 10 of these devices from different manufacturers, I'm not prepared to say that there's nothing to the notion that hitting a lead-acid battery with the right kind of pulse can't do anything good. In fact, I think that there's some reason that a government agency (the military?) should sponsor a well-funded, highly scientific longitudinal test to see if there's anything to the idea. It may well be that with some batteries in certain circumstances a pulsing regime of a certain technical characteristic might have some benefit in restoring capacity and prolonging battery life.

However, no such testing has been done so far, to my knowledge. And there's nothing I've found to suggest that the available devices we've tested really do anything.

I have 12 of them sitting in my basement at the moment. I haven't bothered to install them on my boat (with a total of 8 T-105 deep-cycle batteries) or in my ham shack (with 2-T-105s), or even leave them on some of our test batteries which I still have (four golf-cart gels), because I have no confidence that they'll do anything useful.

However, I do have confidence that a PWM based smart battery charger (like the Iota models, of which I have two) work very well in maintaining battery capacity over time. They do a better job than even very high-end smart chargers like the Victron MultiPlus on my boat.

BTW, I agree with HelloSailor re: milspec....it really means very little if anything. And, the fact that the military may or may not be using these devices says little about their efficacy or their worth in the real world.

Bill

[Roy M]

Okay guys, I give. By the way, how long do your boat batteries last? Just asking, of course, not making any implications.