Crown Battery 75S

- Lead Acid Motive Power Batteries can become unbalanced or sulfated if they are not recharged or equalize charged on a regular basis

Likewise over-discharging or unbalanced discharge can cause low uneven cell voltages. The treatment for restoring the battery to its full potential involves charging and discharging the battery in a very tightly controlled manor

This is a last resort remedy in order to salvage a battery that's been allowed to get into this condition. This may or may not be successful, as sulfate is extremely hard to remove from the cell plates and if let in this condition, may not be reversible

A. Charge the battery as normal to a fully charged condition.

B. Record all individual cell voltages and specific gravities. These readings will be used later to measure how successtul the treatment was.

C. Starting with a cool (less than 80°F) fully charged battery, charge the battery at 2.5 amps per 100 amps of battery capacity. A 24-85FC-21 has a capacity of 850 A.H. Therefore the charge rate would be 21 amps. Charge the battery for at least 24 hours. Stop the charge, if the battery temperature goes to 120°F or higher.

A. Let the battery cool back down to about 80°F

- Test batteries using three testing instruments

- The specific gravity and open circuit voltage readings are normally in direct proportion to each other; consequently, a voltmeter or hydrometer can be used to check the battery

- The use of the voltmeter is a faster method of approximating the individual cell state of charge and can reduce dramatically the time required for routine battery checking. When using the voltmeter method, take specific gravity readings on the two cells having the highest and lowest voltage readings

- This will confirm both cells state of charge and accurately pinpoint the difference in the state of charge between them. The voltmeter is used when on‐charge or on‐discharge voltage readings are needed

- A battery thermometer is read like a normal thermometer. A proper thermometer should have specific gravity correction marked on its scale

- The hydrometer has an extra‐long scale to make readings more accurate. For ease of correcting for temperature, the specific gravity corrections are marked on the scale of the thermometer. The cell tester (voltmeter) has a 1.5 to 3.0 volt scale and an easy‐to‐handle, one‐piece terminal probe;

Warning: This procedure requires trained personnel!

Enter the current battery charge in amperes

If the charger is rated higher than the connector on the battery, proceed with the following modifications:

After modifications, adjust the charger settings as follows:

Enter the new auto equalize settings

Sign off on the battery opportunity charging

Each cell of a battery has slight differences in uniformity of construction and content. These differences cause some cells to take less charge than the other cells in the battery. After a while the state of charge of the cells, which require more charge than the others will drift back in capacity and the battery will not deliver its full capacity

To bring the cells with a lower state of charge up to the same level as the others, the battery is given an "equalizing charge". The cells with a higher state of charge will be somewhat overcharged in order to bring the cells with a below normal state of charge up to full charge

The recommended frequency of equalization is dependent upon how often the batteries are cycled and the depth of the cycles. The frequency of equalization can dramatically affect the operational costs of the vehicle

Unnecessary equalizing charges, in addition to consuming electricity, can result in significant loss of battery life caused by overcharge. The following examples will give you a good idea of a reasonable battery-equalizing schedule for a specific battery operation

1. For batteries that are cycled only once or twice a week to an average depth of 30%-60%, a monthly equalizing charge is sufficient to keep them fully charged

2. Batteries that are discharged regularly- three or more cycles per week and to an average discharge depth of 60%-80% of their rating- can be kept healthy by equalizing them every two months

3. Batteries that are cycled four to eight times a month at any dept require equalizing about every month to keep them in a healthy condition

4. Batteries that are cycled five or more times a week at an average discharge of 60%‐80% may not need equalizing charges unless stored;

Warning: This inspection requires trained personnel with PPE!

Is the battery still in the vehicle?

If the battery is still in the vehicle, turn off the power switch and unplug the battery from the vehicle

Allow the battery to remain on open circuit (do not charge or discharge) for 30 minutes or longer

Fill in the Crown Battery Inspection Report. Include battery type, serial number, etc.

Read and record the specific gravity and open circuit voltage for all cells of the battery

Read and record the pilot cell temperature

Record the temperature-corrected specific gravity readings. Use a temperature correction thermometer. Use the pilot cell temperature for the temperature correction of all the cells.

It is not necessary to read the temperature of every cell unless the temperature difference between center cells and outside cells of the battery is 12°F or more