Arild, There has been some evidence that the pulse charging technology was helpful in preventing sulfatation of plates. Can you see using this on a routine basis with batteries which are 80% charged regularly as a helpful technology today? The other factor which is present in most of the vessels, is that although at anchor the batteries are under charged, when the vessel comes to a marina, or is on a passage, she will fully charge the batteries. Bob Austin

> Arild, > There has been some evidence that the pulse charging technology was > helpful in preventing sulfatation of plates. Can you see using this on a > routine basis with batteries which are 80% charged regularly as a helpful > technology today? > Bob Austin REPLY Yes I can! Prevention is always better than a cure. A minor correction in terminology. Sulfation is the natural result of discharging a lead acid battery. Sulfation is a normal consequence and cannot be avoided; However . . . What the pulse technology does is prevent the sulfate from forming hard crystals that cannot be reversed during the next recharge cycle. Lead sulfate begins to harden within a few hours. Heat exercerbates the process. If you have enough battery capacity to run a week in between recharge there is a lot of old lead sulfate that has already hardened from the first day's discharge. Running a genset to only bring the charge back up to 80% will not reverse the oldest sulfate formation. Even if you do get to shore power once a month it will be too late to reverse this old and stubborn deposits. Eventually the plates become covered totally and you have premature cell failure. Just as water ice crystals expand as they freeze, so does lead sulfate crystals even though no temperateur drop is associated with the process. This expansion of lead sulfate crystals tend to break off tiny flakes of the plate surface. This plate shedding is also a cause of battery failure. Modern battery design has a cavity below the plates or porous plastic sleeves around each plate that catches the loose plate material. This prevents plates from shorting out but any material loss from a plate does reduce its capacity to store a charge. So its a double whammy. The lead sulfate serves as a coating to insulate the plate from active electrolyte or else the crystals break off active plate material thus removing it from further service. For battery bank installations that only receive periodic charging, with quiet times in between; my preference is for the Pulsetech modules that are permanently connected to the battery and uses the battery energy to power the oscillator. In theory a battery may contain enough lead for 6 - 10 years of normal intermittent use. For daily cycling on a full time liveaboard boat you are more likely to get 5-7 years use if depth of discharge is 50% - 70%. My preference is for shorter daily charging sessions, instead of longer sessions that only take place once or twice a week. It removes the accumulated lead sulfate befoer it hardens too much. Although I have salvaged supposedly "dead" batteries by treating them with pulse technology I will not claim it was a 100% recovery because they had been sitting for weeks if not months before I got to them. Some permanent damage always resulted. I once recovered a battery that had been abandoned for 18 months and it went back into service for another couple of years in my brother in law's camper trailer. regards Arild