Sulfation

Sulfation

Sulfation reduces battery life, battery power & ultimately leads to a premature death

What is Sulfation?

Sulfation is the creation of lead sulfates. It is a natural and necessary part of a battery's life and occurs whenever the battery is in a state of discharge, i.e. whenever the battery is NOT charging. Over time as the battery discharges, the electrolyte solution inside the battery turns into water and the lead plates become covered with lead sulfate crystals.

There is enough reactive material in lead-acid batteries to keep them operating for at least 8-10 years. However, the average life of a battery, depending on usage, is only six to 48 months and only 30% of all batteries actually reach the 48-month point. This short life span is due to a series of problems caused by sulfation buildup on the battery plates.

As a battery ages through use or sits unused for periods of time, these lead sulfate crystals enlarge and eventually build-up to the point where they create a physical barrier across the surface of the battery plates. Before long, this build-up can become so dense that a battery is no longer able to accept or release energy.

Sulfate crystals

The image above shows a battery plate covered in heavy sulfation buildup. This sulfation acts as an insulation barrier around the battery plates restricting the energy exchange.

While the sulfation process will occur sooner or later, it can be accelerated through a variety of events including but not limited to:

  1. Extended shelf storage prior to installation. Sulfation buildup begins almost the moment battery acid is added to a battery, so as new batteries sit in storage or on a store shelf, they will quickly become sulfated. This means a battery could literally fail soon after it is installed in a vehicle, even though it is "new."
  2. Extended period of inactivity of a vehicle.
  3. Corrosion of the battery terminal which increases resistance in the charge cycle, thus developing an undercharge situation.
  4. Maintaining a state of discharge.
  5. Temperature. For example, when the ambient temperature rises, the rate of sulfation can double for every 10° increase in temperature. That means that if the outside temperature goes from 75° to 95°, sulfation can occur 400% faster than normal. Cold conditions can cause the vehicle's fluids to thicken. This means it will take even more power to start the vehicle, so the battery has to discharge even further and the result is a faster buildup of sulfates on the lead plates. Also, keep in mind that the battery's electrolyte can actually freeze if the battery is in an advanced state of discharge, and this could damage the lead plates. At 1.270 specific gravity (100% charged), it will freeze at -83° F; at 1.200 it will freeze at -17° F; and at 1.140 (completely discharged), it will freeze at only 8° F.
    Rate of Sulfation for Temperature chart
  6. An undercharging situation where the battery is maintained at less than maximum voltages, such as on frequently-used vehicles that stop and go constantly. Since the vehicle is moving at slower speeds or idling, the alternator is not charging at an optimum rate. The result is a battery that is not fully charged even though the vehicle is running all day. And since it isn't fully charged, it will begin to sulfate. A vicious cycle is then created because the more the battery sulfates, the less energy it will accept and the battery will be undercharged even more. Ultimately, it too will die.

Sulfates negatively impact battery performance:

  • Reducing the battery's ability to discharge power
  • Reducing the battery's ability to recharge
  • Shortening battery life – 80% of batteries worldwide die prematurely

The most effective cure to the sulfation problem is PulseTech's patented Pulse Technology.