GP Series

Sealed lead acid battery life is determined by many factors. These include temperature, depth and rate of discharge, and the number of charges and discharges (called cycles).

Deep-cycle batteries are used when 50% or more of the capacity is used per cycle. The most common use of deep-cycle batteries is in applications that require deep, repetitive drain, like powerful car audio systems, trolling motors, golf carts, electric wheelchairs, or RV house power sources. Public safety and high performance vehicles are other applications that call for the special characteristics of deep-cycle batteries.

The service design life of a battery varies considerably with how it is used, how it is maintained and charged,  temperature, among other factors.

No. Sealed lead acid batteries do not require the use of water.

A float application requires the battery to be on constant charge with an occasional discharge. Cycle applications charge and discharge the battery on a regular basis.

Routine battery examinations divulge irregularities in the charging system as well as in the batteries. Theprinciple method is to examine the electrochemistry of the battery through hydrometric electrolyte inspection.

As previously discussed, this important examination cannot be accomplished with sealed absorption or gel batteries. Voltage readings alone require experience to interpret. Hydrometric readings will uncover early warnings of overcharging or over-discharging before batteries are damaged.

The state-of-charge and reliability of a lead acid battery can best be determined by the specific gravity of the electrolyte measured directly with a common bulb-type hydrometer with a glass float. We do not recommend the ball float type hydrometer. Specific gravity is a unit of measurement for determining the sulfuric acid content of the electrolyte.

The recommended fully charged specific gravity of marine batteries is 1.255 to 1.265 taken at 80??C More  than .025 spread in readings between fully charged cells indicates that the battery may need an equalization charge.

If this condition persists, the cell is failing and the battery should be replaced. Since water has a value of 1.000,  electrolyte with a specific gravity of 1.260 means it is 1.260 times heavier than pure water while pure concentrated sulfuric acid has a specific gravity of 1.835.

OVER-DISCHARGING is a problem which originates from insufficient battery capacity causing the batteries to be overworked. Discharges deeper than 50% (in reality well below 12.0 Volts or 1.200 Specific Gravity)  significantly shorten the Cycle Life of a battery without increasing the usable depth of cycle.

Infrequent or inadequate complete recharging can also cause over-discharging symptoms called SULFATION.

Despite that charging equipment is regulating back properly, over-discharging symptoms are displayed as loss of battery capacity and lower than normal specific gravity. Sulfation occurs when sulfur from the electrolyte combines with the lead on the plates and forms lead-sulfate.

Once this condition becomes chronic, marine battery chargers will not remove the hardened sulfate. Sulfation can usually be removed by a proper desulfation or equalization charge with external manual battery chargers.

To accomplish this task, the flooded plate batteries must be charged at 6 to 10 amps. at 2.4 to 2.5 volts per cell  untill all cells are gassing freely and their specific gravity returns to their full charge concentration.

Sealed AGM batteries should be brought to 2.35 volts per cell and then discharged to 1.75 volts per cell.

This process must be repeated until the capacity returns to the battery. Gel batteries may not recover. In most cases, the battery may be returned to complete its service life.  CHARGING Alternators and float battery  chargers including regulated photo voltaic chargers have automatic controls which taper the charge rate as the batteries come up in charge.

It should be noted that a decrease to a few amperes while charging does not mean that the batteries havebeen fully charged. Battery chargers are of three types. There is the manual type, the trickle type, and the automatic switcher type.