Myth: The worst thing you can do is overcharge a lead acid battery. Fact: The worst thing you can do is under-charge a lead acid battery. Regularly under-charging a battery will result in sulfation with permanent loss of capacity and plate corrosion rates upwards of 25x normal.
A lead acid battery left in storage at moderate temperatures has an estimated self-discharge rate of 5% per month. This rate increases as temperatures rise and as the risk of sulfation goes up. Sulfating: This is a buildup of lead sulfate crystals and it occurs when a lead acid battery is left sitting without a full charge.
By discharging a lead acid battery to below the manufacturer’s stated end of life discharge voltage you are allowing the polarity of some of the weaker cells to become reversed. This causes permanent damage to those cells and prevents the battery from ever being recharged.
Besides age-related losses, sulfation and grid corrosion are the main killers of lead acid batteries. Sulfation is a thin layer that forms on the negative cell plate if the battery is allowed to dwell in a low state-of-charge. If caught in time, an equalizing charge can reverse the condition.
Lithium-ion technology commonly provides 20-50 percent more usable capacity and operational time depending on the discharge current. This allows you to substitute your lead acid battery with a much smaller, lower-capacity lithium-ion battery to achieve similar results and run time.
Sulfating: This is a buildup of lead sulfate crystals and it occurs when a lead acid battery is left sitting without a full charge. Even if you are giving your battery a small charge such as putting it in the car and letting it idle, this is still not enough to combat the self-discharge that can take place.