Technical Bulletin
About Battery Performance and Pulse Technology

Our experience shows that 84% of lead acid batteries are scrapped because of sulfation. Sulfation occurs when a battery is discharged. The deeper the battery is discharged, the more serious is the sulfation. The sulfation is an insulating film which covers the plates. The sulfur molecules which form the sulfation are now absent from the electrolyte, causing the electrolyte to become inefficient. A battery relies on clean plates and strong electrolyte to both receive charging current and offer strong discharge current. A sulfated battery can do neither.

An energetic recharging process will remove some, but not all of the sulfate. Eventually, after a certain number of discharge cycles, the battery plates are either coated with enough sulfate that it is impossible to achieve an efficient recharge (as in the case of motive power batteries), or the plates are eroded, and the battery is scrap (automotive batteries).

Battery construction plays a pivotal role in the success rate of battery rejuvenation with pulse technology. This is the reason we recommend the use of pulse technology as a preventive maintenance tool.

Often by the time an automotive battery fails a load test due to sulfation, the battery plates are heavily eroded, the plate materials having fallen to the bottom of the battery. This occurs because the plates are manufactured to be of high porosity (much like a piece of Swiss cheese), to maximize surfacial area and to allow maximum amperage discharge for a short period of time (eg. starting a car engine). This allows construction of a compact battery with short term, high amperage capability. The sulfate enters the pores on the plates, and as it advances towards the crystaline state, it greatly expands. The crystal growth causes plate material to break off much the same way as the formation of ice in a crack of a rock will cause pieces of the rock to break off.

Another cause of plate erosion occurs when the batteries are in an undercharged state. Battery theory states that the cell voltage should read 2.5 volts per cell (ie. 15 volts in the case of a 12 volt battery) from time to time to allow the negative plate to "form". If this does not occur, the negative plate remains mushy and subject to erosion from motion, vibration, etc. On automotive systems, voltage regulator settings normally do not exceed 14.2 volts. Battery theory goes on to state that a 12 volt battery must receive a minimum of 14.1 volts to maintain a charged state. A recent test on a highway tractor fleet indicated that the highest voltage (at the battery) was 13.9 volts (no electrical load from the accessories). With the addition of the electrical load from the cab of the tractor (heater, lights etc.) the voltage dropped to 13.7 volts, and with the addition of the trailer lights, the voltage fell to 12.3 volts. Average battery life in highway tractors is one year. The reason for this poor battery life is that the batteries are maintained continuously in an undercharged state. With the addition of Can-PULSE Charge Partner technology, the system voltage will recover to over 13 volts, and the momentary pulsing will raise cell voltages (during the pulse) to over 15 volts. This momentary continuous pulse voltage in excess of 15 volts removes sulfation, "forms" the negative plate, and allows the battery to be maintained in optimum condition.

In the case of motive power batteries, the plate construction is tubular, not having the porous qualities of automotive batteries. These batteries are designed to discharge large amounts of amperage over a long period of time, and do so because the physical size of the plates is very large. Because the plates are not porous, the sulfate simply insulates the exterior of the plate, not allowing an efficient charge to occur. The sulfation effect determines the life cycle rating of a motive power battery. Use of the Can-PULSE Motive Power Battery Maintenance System will often remove the sulfation in two charge/discharge cycles, restrengthening the electrolyte, and allowing the battery to return to service.

Another phenomenon in motive power applications is the "dead cell". During a very deep discharge cycle, some plates within a cell will reverse polarity. During recharge these cells must first receive energy to return to a "zero" state, and then begin recharging once proper polarity is achieved. The surrounding cells have efficiently recharged as they did not first have to return to a zero state. However the cells with reversed polarity plates depress battery voltage, causing the charger to provide strong current. The effect is severe boiling of the fully charged cells, and potentially mechanical damage to the battery. The CanPULSE Motive Power System will eliminate this problem during recharge.

It is often not just sulfation, but its associated mechanical damage, which causes premature battery failure. In the case of automotive batteries plate erosion, post expansion (very common in ambulances), and cell freezing are some examples of mechanical damage caused by sulfation. In the case of motive power batteries cracks to the top of the case, shorted cells, and significant corrosion are leading examples of mechanical failure.

Specific gravity (S.G.) is a measurement of the strength of the electrolyte. In the case of automotive batteries, specific gravity of 1.275 or greater is considered acceptable. Specific gravity of less than 1.250 would indicate a sulfated battery which would likely fail in cold weather. When pulse technology is applied to a battery with S.G. of 1.275 (considered acceptable) and raised to 1.300 the result is significantly increased cranking power. The specific gravity scale can tend to be misleading, and one must understand that in the case of automotive batteries, satisfactory performance occurs only when the S.G. is 1.275 or greater.

Batteries ultimately must pass a resistive load test before being returned to service. Batteries with high specific gravity which fail a load test have mechanical damage and should be disposed of in an environmentally responsible manner.

What does Can-PULSE technology have to do with all of the above? Well, first let's discuss in simple terms how a lead acid battery works. The working components of a battery are the lead plates and the sulfuric acid electrolyte. Electrical energy is transferred to and from the plates by sulfur molecules in the electrolyte. Clean plates and strong electrolyte (lots of sulfur available to transfer the energy) allow good battery performance. However when the battery is being discharged , some of the sulfur molecules adhere to the plates, forming a sulfate layer. With an energetic recharge (which often does not occur), most of this sulfur is energized and returned to the electrolyte. However, some sulfur molecules bond together and form a stronger bond to the battery plates which normal charging voltage cannot remove. Can-PULSE technology products deliver very energetic pulse energy to the battery plates, which energizes all of the adhered sulfur molecules. As the sulfate disappears, the sulfur returns to the electrolyte. Once again the plates are clean and the electrolyte is strong, ensuring peak battery performance.

It is recommended that Can-PULSE products are used as a preventive maintenance tool, to prevent mechanical battery damage as discussed earlier.

If you have any questions regarding Can-PULSE products, or require more information, please do not hesitate to call Solartech Products Canadus Power Systems at 440–232- 3100, at (204) 885-4652 or Fax fax us at (204) 888-2046440-232-3130, or e-mail to us at info@solartechcanadus.com.

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