Sulfation pulse treatment surprise
There are roughly 60 billion dollar's worth of lead-acid batteries, for starting automobile engines, in use worldwide. Every one of them is destined to work for a certain number of years, then to stop working. The consumer is obliged, by virtue of automobile ownership, to buy replacement batteries. The consumer is a reluctant buyer, is likely to buy on price which, in turn, puts battery manufacturers under commercial pressure. This is most likely why the average lead-acid car battery has a relatively modest life expectancy.
Advertising worth millions of dollars has been insisting that sulfation is the primary cause of battery failure. This has formed the basis of what many people believe to be true. We have researched the entire spectrum of recorded know-how on the subject of making lead-acid batteries last longer. We have read numerous of patents, articles, documents, reports, comments, letters and advertisements and we have run hundreds of tests. This is what we found.
The developed world operates between 500 and 800 motor vehicles per 1000 population - in other words, nearly one lead-acid battery per person. Nearly four hundred million batteries. Auto part retailers, by rights, should be selling huge volumes of pulse desulfators. Some of the makers of pulse desulfation products should have grown big enough to become publicly traded enterprises. Yet nothing has happened. Pulse desulfators are sold now as they were when they first appeared twenty years ago, in ones and twos, predominantly by small scale mail order specialists.
We initially liked the concept of sulfation pulse treatment very much and believed we understood it. We were very surprised on searching patent databases around the globe, to find 61 patents strung out like pearls on a necklace in time - all issued after 1991 - successively describing each and every previous invention as flawed, then each in turn going on to propose a radically different pulsing technique. Electrical, as well as magnetic, mechanical and ultrasonic - from intense pulses lasting mere nanoseconds - pulses lasting milliseconds - square wave on-off - square wave on and triangular off, at a variety of intervals. Some designs use the battery itself, to power the pulsing unit, to send pulses back to itself - rather irrationally risking discharging the battery until it is unable to perform its intended task. Pulsing at various states of charge, pulsing at a wide variety of rates, steady pulsing, patterned pulsing, resonant pulsing. Some claim that pulsing at the crystal resonance frequency of sulfur, at 3.26 MHz, is best. What they saw was the self-resonance of the battery connectors, made an assumption. There is no sulfur in a lead-acid battery, only sulfate of hydrogen, (sulfuric acid), and sulfate of lead, (lead sulfate).
Pulse charging is an old technology. Pulse treatment is relatively new. Wilford B Burkett has been incorrectly credited for inventing battery pulse rejuvenation in the late 1960s, early 1970s. He used pulsing to fast-charge batteries. Battery rejuventation or desulfation by means of pulsing was invented by Carl Edward Gali, (1928-2009), (retired microchip designer, Texas Instruments), US Patent 5,063,341, filed Oct 16, 1990, issued Nov 5, 1991. [Click to view the first patent, 1. USPTO: US Pat 5,063,341 or 2. Google: US Pat 5,063,341 and the re-examined patent, 3. US Re. 35,643, Oct 28, 1997 pdf.]. His patents were evidently not very strong. Lead-acid battery desulfation pulse technology quickly began attracting large numbers of enthusiasts, manufacturers and distributors worldwide.
The diversity among subsequent pulsing patents provides a convenient and surprisingly accurate way of determining the true level of understanding of the technology. The databases show the pulse technology patent subject matter is extraordinarily widely scattered, confirming there is definitely something not right with this technology.
We believe it to be highly significant that pulsing began gaining popularity in the early 1990s, only after all the major battery manufacturers had introduced low-maintenance and maintenance-free automobile batteries. These batteries have lead-calcium alloy grids. Lead-calcium batteries overwhelmingly fail due to something known in the trade as "passivation" or "open circuit". It has been described by battery technologists as the "antimony-free effect".
Lead-calcium alloy develops an ultra-thin, very poorly conducting tetragonal lead oxide, (alpha-PbO), layer on the surfaces of the positive plate grids over time, leaving the positive active material in the positive plates isolated from the supporting positive grid structure. The PbO layer begins as PbSO4 and forms over time as result of reactions that have the effect of raising the pH in the confines of the junction. (See reference at the bottom of the page.) Battery manufacturers use tin to control this oxide layer. This is far from straightforward. Addition of more than 1.5% tin to the alloy reduces the passivation effect - critically, at 0.6%, tin actually provides a worsening a of the effect. Tin is expensive, so as little as possible is used, with unpredictable results. There are more than 90 patents describing tin, as well as other metals, alloyed with, or plated onto positive grids - suggesting this too, is a highly problematic technology. Silver is even more beneficial but is excruciatingly expensive. Before lead-calcium, lead-antimony was the preferred alloy. Lead-antimony has always been absolutely 100% trouble-free in this regard.
Then why change? Very good question. Lead-calcium technology batteries use one-eighth the amount of water of lead-antimony, plus they can be made totally maintenance-free by hydrogen/oxygen recombination technology. Lead-calcium grids cost less than lead-antimony grids. Battery manufacturers are very quick to play follow-the-leader to make sure there is little to chose between batteries. Evidently maintenance-free is perceived as important, reasonable battery life less so. These Pinocchios are quick to describe AGM and Gel as providing "optimum performance" and "superior deep cycling" - but prefer not to disclose the actual cycling life figures. Welcome to the throw-away society!
The problem presents with the battery refusing to crank the engine. Then, when the battery is put on charge, its voltage rises almost immediately, as if it is already fully charged. All the external symptoms, (including low SG in flooded batteries), are identical to sulfation, yet this is definitely not sulfation. The application of strong, high frequency pulses, pulses with fast rise-times, acting substantially in the same direction as the battery charging current, breaks down the ultra-thin oxide insulating layer and in that way has been restoring battery ampere-hour capacity to a serviceable level.
Our researchers ran a series of experiments to find out first hand what effect pulsing has on sulfated batteries. Our testing was performed on battery cells that we built in glass containers, so that we could see precisely, from the beginning to the end, what was happening to the battery plates. Fully charged, fully discharged and sulfated plates all have different colors that are not difficult to distinguish from each other. We had battery plates that had been carefully stored, unused, under battery acid for five years. The plates were 100% sulfated. We incorporated these plates in our test cells.
We used a dual-beam 100 MHz oscilloscope and a coaxial low inductance current shunt in our testing. Sharp nanosecond/ microsecond pulses produced "pings" or damped sinusoidal oscillations. We examined these oscillations closely. The current wave was 90 degrees out of phase with the voltage wave, due to the resonance of the circuit inductance and the circuit capacitance, showing that virtually all of the pulsing energy ends up being wastefully dissipated in the wiring and circuit resistance, instead of going into the battery. (In heavy current electrical engineering this is known as a power factor of zero.) Longer lasting millisecond pulses produce current and voltage waves that are in phase and are therefore far more efficient. The test cells were pulsed in every way it was possible to do so, for weeks on end. They did not, we repeat, they did not become nearly sufficiently enough desulfated.
A lead-acid battery cell is in some respects similar to an electroplating cell. Fortunately, the solubility of lead in sulfuric acid is so low, when a lead-acid cell is connected to a power source, it is charged and the amount of electroplating that occurs is negligible. Charging takes preference over electroplating - except when the cell is pushed significantly over 2.6 volts, for example, when it is pulse charged. A lead-acid cell that is pulse charged becomes a more efficient electroplating cell. If pulsing is overdone, lead metal will be transferred from the positives to the negatives, the postive grids will become corroded and the negative plates will develop mossy dendrites. Electroplating causes metal filaments to penetrate the pores of the separators progressively from the negative to the positive plates, resulting in shorting and premature cell failure. (See Article - Lead-Acid & Internal Electroplating, Movie No 4). Pulsing increases battery temperature. The wattage lost due to the battery internal resistance rises with the square of the current: W=I²R multiplied by the duty cycle. Pulses that are 10%-ON, 90%-OFF increase the heat loss ten times.
We are not suggesting pulsing does not work at all. The average energy in the pulses of an electrically powered pulsing unit can definitely charge a battery. The energy content in inductive and capacitive discharge pulses automatically adjusts to battery volts and amps and that part is a good idea. Pulsing works very well on batteries that have become "tired" and have acquired a relatively mild form of sulfation diffused within their plates, and it works on "open circuit" batteries. It definitely does not work on heavily sulfated batteries. We subjected six golf-cart batteries that had last been used three years previously to desulfation treatment using a large industrial-grade pulse desulfator. All six had been down to less than 2 volts. All six remained sulfated.
Sulfation is a problem but it is a minor problem, affecting mainly automobile-type batteries. It has long been promoted as a universal lead-acid problem by venturers who seek to profit from selling desulfation products. This attracts many newcomers, who scramble to get into what they believe to be a very easy line of business - only to find it is next to impossible to make money.
If Tom wants to sell a desulfation kit and Dick is willing to pay the asking price, that's free enterprise at work and no one has any right to stand in the way of the transaction. If Harry believes that desulfation kits do not work and says so without naming sellers and buyers, that's freedom of expression.
- The battery community's understanding of how lead-acid works comes from long experience, scientific investigation, extensive testing, hard data and facts -
- but what the battery community knows about lead-acid when it is put to work by the user is based on recollections, interpretations, opinions, anecdotes and beliefs.
If, as is claimed, desulfation removes a layer of white sulfate that forms over the battery plates, why haven't the makers of desulfation products provided proper evidence that is easily understood and that can be believed - a one-shot, continuous time lapse movie showing a fully sulfated battery in a transparent case undergoing desulfation and showing restoration of capacity?
The problem with studies run by universities on behalf of corporations is that they can tailor their evaluation protocols to provide information in a way that can support or dispute claims made about commercial products. Beware of customer testimonials. Try looking at the situation from the testimonial writer's perspective. The writer appears to be accepting responsibility for latent defects in a manufacturer's product. Who would take this kind of risk?
Sulfation is a term that came into use during the early days of the lead-acid battery. The meaning of the word has expanded to imply authority to include and justify every conceivable reason for the eventual performance deterioration and failure of lead-acid batteries. However..........
- Lead-acid batteries that receive the best possible care, are brought to full state-of-charge regularly, consistently last the longest --- eventually wear out as result of the effects of positive grid corrosion.
- Lead-acid batteries that, for a large variety of different reasons, are consistently undercharged, are not brought to full state-of-charge regularly --- fail prematurely as result of the effects of sulfation.
Related Article: Sulfation Remedies Demystified
Related Article: Why understanding corrosion is important
If you are planning to set up the kind of business that can be run from home, always remember, your direct competitors will be doing this as well. No matter how good you are, how much better you are, in this day and age with unemployment spurring business start-ups, inevitably, this kind of competition drives down prices, wipes out profits.
In the early 1980s there were 6.5 million doctors in the world - all convinced that stomach ulcers were caused by stress. Two unknown doctors, Barry Marshall and Robin Warren from Perth, Australia discovered that stomach ulcers were caused by a bacterium called Helicobacter pylori. No more major operations and no more lifelong disability. A course of antibiotics would cure the problem. Simple. They were ignored by the medical profession for 10 years. Eventually it was accepted they were right and that 6.5 million doctors had been wrong all along. The two received the Nobel Prize in medicine in 2005 for their discovery.
This was not the first time all the doctors in the world have been wrong and there was one who argued against a common misconception and was right. It took ages and untold unnecessary deaths before doctors would accept that germs cause disease. It sounds crazy today but it is perfectly true. The moral of this story is that if someone tells you that a long-held belief is wrong and explains in great detail why it is wrong - yet you ignore the advice because you want to believe that it is the majority that is always right, you are making the same mistake.
Thank you for reading this page.
Research by a group of eminent scientists, LT Lam, H Ozgun, OV Lin, JA Hamilton, LH Vu, DG Vella and DAJ Rand, (CSIRO), showed that pulse charging of lead-calcium grid alloy lead-acid batteries breaks down the non-conducting lead oxide barrier layer progressively into expanding islands of conduction with application of pulsing. "Pulsed-Current Charging of Lead-Acid Batteries -", Journal of Power Sources 53 (1995), pages 226-227. [If you are seriously interested in pulsing technology, we recommend you Google the name of the title and the name of the first scientist on the list, as one sentence, to obtain a PDF of the report. (The link to this report is www.vershv.narod.ru/sdarticle.pdf)].