Why is lead acid battery rechargeable

The Charge Wizard will automatically provide an Equalizing Charge every 21 hours for a period of 15 minutes, when the battery is fully charged and not in use. One disadvantage of recharging a lead acid battery at a fixed voltage of Increasing the charge voltage to Again, this is a standard feature on our Marine Chargers. Another disadvantage of recharging a lead acid battery at a fixed voltage of To prevent this from occurring the charging voltage must be reduced to At a charging voltage of However, this lower voltage does not provide enough gassing to prevent a battery condition called Battery Stratification.

Battery Stratification is caused by the fact that the electrolyte in the battery is a mixture of water and acid and, like all mixtures, one component, the acid, is heavier than water. Therefore, acid will begin to settle and concentrate at the bottom of the battery see figure 8. This higher concentration of acid at the bottom of the battery causes additional build-up of lead sulfate sulfation , which reduces battery storage capacity and battery life.

In order to prevent Battery Stratification , an Equalization Charge increasing charging voltage to This Equalizing Charge feature is standard on our Marine chargers. As you have learned, in order to properly charge and maintain a lead acid battery you must use an intelligent charging system. Progressive Dynamics, Inteli-Power Series RV converters with a Charge Wizard installed, or one of our Inteli-Power Marine Battery Chargers will provide the intelligent charging system your battery needs for a long life, with low maintenance.

Battery Construction Lead acid batteries used in the RV and Marine Industries usually consist of two 6-volt batteries in series, or a single volt battery. Lead Acid Battery Discharge Cycle.

Answers to Common Questions about Batteries. Use the search above to find an answer!!!! Wizard equipped converters. Equalization when applied in the conventional sense to LA battery chargers, means up to The equalization cycle that we use is mild, This has been proven to be good at reducing sulfation in the Lead Acid Wet batteries. It also has no effect on AGM. Do lead acid batteries discharge when not in use?

All batteries, regardless of their chemistry, will self-discharge. The rate of self-discharge for lead acid batteries depends on the storage or operating temperature. At a temperature of 80 degrees F. A battery with a amp hour rating would self-discharge at a rate of approximately five amps per week. Keeping this in mind if a AH battery is stored for four months 16 weeks winter without being charged, it will loose 80 amps of its amp capacity.

It will also have severe sulfation, which causes additional loss of capacity. Keep your batteries charged while not in use! Lead acid batteries do not develop any type of memory. Discharging it below this point or Equalizing should be performed when a battery is first purchased called a freshening charge and on a regular basis every 10 discharge cycles or at least once a month.

Reduced performance can also be an indicator that an equalizing charge is needed. An equalizing charge for a 12 volt battery requires that it be charged with a voltage of at least An equalizing charge prevents battery stratification and reduces sulfation, the leading cause of battery failure. How often you use and recharge your batteries will determine the frequency of watering.

Also, using batteries in a hot climate will require more frequent watering. It is best to check your battery water level frequently and add distilled water when needed. This eliminates the need for vigorous equalization charging which helps mix the electrolyte with the water in flooded batteries. Both AGM and Gel batteries are good for off-grid applications where several days of autonomy is preferred and charge rates are more likely to remain low.

Water inside the battery is less likely to freeze since it does not separate from the electrolyte which means sealed batteries are prefered in colder temperatures. Also, Gel batteries are a little better equipped for more extreme temperatures, both hot and cold, than AGM.

The following graph shows the sequence of stages. When the battery has recharged to the Absorption voltage set-point, constant-voltage regulation is used to maintain battery voltage at the Absorption set-point.

This prevents heating and excessive battery gassing. The battery is allowed to come to full state of charge at the Absorption voltage set-point. The battery must remain in the Absorption charging stage for a cumulative — minutes, depending on battery type, before transition to the Float stage will occur.

However, Absorption time will be extended by 30 minutes if the battery discharges below 50 Volts the previous night. The Absorption set-point is temperature compensated if there is an internal temperature sensor or an RTS is connected.

When the battery is fully recharged, there can be no more chemical reactions and all the charging current is turned into heat and gassing. The float stage provides a very low rate of maintenance charging while reducing the heating and gassing of a fully charged battery.

The purpose of float is to protect the battery from long-term overcharge. Once in Float stage, loads can continue to draw power from the battery. In the event that the system load s exceed the solar charge current, the controller will no longer be able to maintain the battery at the Float set-point. Should the battery voltage remain below the Float set-point for a cumulative 60 minute period, the controller will exit Float stage and return to Bulk charging.

The Float set-point is temperature compensated if there is an internal temperature sensor or an RTS is connected. Certain battery types benefit from a periodic boost charge to stir the electrolyte, level the cell voltages, and complete the chemical reactions. Equalization charging raises the battery voltage above the standard absorption voltage so that the electrolyte gases.

The duration of the equalize charge is determined by the selected battery type for the controller being used. The Equalization Time is defined as time spent at the equalization set-point. If there is insufficient charge current to reach the equalization voltage, the equalization will terminate after a certain period of time with battery voltages above the Absorption voltage setpoint. This is done to avoid over gassing or heating the battery.

If the battery requires more time in equalization, an equalize can be requested using the TriStar Meter or push-button to continue for one or more additional equalization cycles. The Equalization set-point is temperature compensated if there is an internal temperature sensor or an RTS is connected. Why Equalize? Routine equalization cycles are often vital to the performance and life of a battery — particularly in a solar system.

Use this practical to demonstrate the chemistry behind rechargeable batteries, using a lead—acid accumulator cell. Some electrochemical cells are rechargeable — the electrode reactions are reversible and the process can be repeated many times.

Such cells can be used to store electricity. This experiment can be used as a class practical or demonstration. Students learn how to construct a simple lead—acid cell consisting of strips of lead and an electrolyte of dilute sulfuric acid. The cell should then be charged for different lengths of time, before being discharged through a light bulb. Students measure the time the bulb remains lit, plotting a graph of this time against the charging time to show the relationship between the electrical energy put into the cell and the energy released.

Without going into the detail of the electrode reactions, this experiment can be used as a demonstration or class exercise to investigate a reversible electrochemical cell in the context of alternative energy sources for vehicles, or energy storage.

To date the lead-acid accumulator has proved to be the only widely used source of energy for electrically powered vehicles. Other types of electrochemical cell, especially fuel cells, are now being developed and tested on the road. Some of the criteria for a commercially viable cell can be discussed. At advanced level the electrode processes could be outlined in more detail as examples of redox reactions that can be reversed many times in an electrochemical cell.

Although car battery testing using the density of the electrolyte has become less common, its relationship to the overall cell reactions, on charging and discharging the lead accumulator, could also be pointed out. Students should be able to identify which way electrons are flowing in the cell when it is charging and discharging from the electrode polarities.

At advanced level this could be linked to the electrode reactions below, which assume an initial layer of insoluble lead II sulfate on the electrodes after immersing the lead in the acid. Thus during charging the sulfuric acid concentration rises, and during discharge it falls.

This has caused explosions in the past when the electrolyte level in batteries has been investigated with the aid of a lighted match! The advantages of this cell reaction for use in a commercial battery could be discussed, eg the formation of insoluble lead or lead compounds on the electrodes during charge and discharge, the only changes in the electrolyte being a change in concentration.

Commercial cells need to be robust, cheap to construct and, for certain applications, able to sustain large currents.