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How does a battery work?

A battery consists of an assembly of electrodes, separators, electrolyte, container and terminals.

What is an AGM battery?

An AGM battery is a completely maintenance-free lead-acid electric storage battery that is sealed using special pressure valves and should never be opened. Absorbed Glass Mats are used to absorb almost all of electrolyte and provide channels for oxygen gases which will be participated in recombination reaction to prevent the escape of hydrogen and oxygen gases.

What is a Gel battery?

A Gel battery design is typically a modification of the standard lead acid automotive or marine battery. A gelling agent is added to the electrolyte to reduce movement inside the battery case. Many Gel batteries also use one way valves in place of open vents, this helps the normal internal gasses to recombine back into water in the battery, reducing gassing. "Gel Cell" batteries are non-spilling even if they are broken. Gel cells must be charged at a lower voltage (C/20) than flooded or AGM to prevent excess gas from damaging the cells. Fast charging them on a conventional automotive charger may be permanently damage a Gel Battery.

What are the differences between Gel batteries and AGM batteries?

In the Gel battery, the electrolyte dose not flows like a normal liquid. The electrolyte has the consistency and appearance of petroleum jelly. Like gelled electrolyte batteries, absorbed electrolyte batteries are also considered non-spillable – all of liquid electrolyte is trapped in the sponge-like matted glass fiber separator material.

The “acid-starved” condition of Gel and AGM batteries protects the plates during heavy deep-discharges.

The Gel battery is more starved, giving more protection to the plate; therefore, it is better suited for super-deep discharge applications.

Duo to the physical properties of the gelled electrolyte, Gel battery power declines faster than an AGM battery’s as the temperature drops below 32℉. AGM batteries excel for high current, high power applications and in extremely cold environments.

What is the battery rating?

CCA = Cold Cranking Amperes at 0℉ (-17.8℃) Cold cranking amperes equal the number of amperes a new, fully charged battery will deliver at  0℉(-17.8℃) for thirty seconds of discharge and maintain at least 1.2 volts per cell(7.2 volts for a 12-volt battery)

CA = Cranking Amperes at 32℉ (0℃)Same as above, test at 32℉ (0℃)

RC=Reserve Capacity at 80℉ (27℃)The reserve capacity is the time in minutes that a new, fully charged battery can be continuously discharged at 25 amperes and maintains at least 1.75 volts per cell (10.5 volts for a 12-volt battery).

Minutes discharged at 50, 25, 15, 8, and 5 AmperesMinutes discharged is the time in minutes that a new, fully charged battery will deliver at various currents and maintains at least 1.75 volts per cell. These are nominal or average ratings.

Ampere Hour Capacity at 20, 10, 5, 3 and 1 Hour RatesAmpere hour capacity is a unit of measure that is calculated by multiplying the current in amperes by the time in hours of discharge to 1.75 volts per cell. These are nominal or average ratings.

Examples 5 amperes for 20 hours (5×20) = 100 AH @ the 20-hour rate 10 amperes for 3 hours (10×3) = 30 AH @ the 3-hour rate 20 amperes for 1 hours (20×1) = 20 AH @ the 1-hour rate Therefore, if you have am application that requires a draw of 15 amperes for 5 hours, you would need a 75 AH battery (@ the 5-hour rate). Examples 5 amperes for 20 hours (5×20) = 100 AH @ the 20-hour rate 10 amperes for 3 hours (10×3) = 30 AH @ the 3-hour rate 20 amperes for 1 hours (20×1) = 20 AH @ the 1-hour rate Ampere hour capacity is a unit of measure that is calculated by multiplying the current in amperes by the time in hours of discharge to 1.75 volts per cell. These are nominal or average ratings.

Do batteries self-discharge when not in use?

All batteries, regardless of their chemistry, self-discharge. The rate of self-discharge depends both on the type of battery and the storage temperature the batteries are exposed to. However, for a good estimate, IBT batteries self-discharge approximately 3% per month at 25℃(77℉).

Are lead acid batteries recyclable?

Lead acid batteries are 100% recyclable. Lead is the most recycled metal in the world today. The plastic containers and covers of old batteries are neutralized, reground and used in the manufacture of new battery cases. The electrolyte can be processed for recycled waste water uses. In some cases, the electrolyte is cleaned and reprocessed and sold as battery grade electrolyte. In other instances, the sulfate content is removed as Ammonia Sulfate and used in fertilizers. The separators are often used as a fuel source for the recycling process.

What is sulfation of batteries?

Sulfation is the formation or deposit of lead sulfate on the surface and in the pores of the active material of the batteries' lead plates. If the sulfation becomes excessive and forms large crystals on the plates, the battery will not operate efficiently and may not work at all. Common causes of battery sulfation are standing a long time in a discharged condition, operating at excessive temperatures, and prolonged under or over charging.

What is the battery cycle life?

One cycle of a battery is a discharge from full charge to full discharge and a return to full charge again. The total number of cycles a battery can perform before failure is called its Cycle Life. Moat battery manufacturers will not discus the Cycle Life of their product. Many advertised Deep Cycle batteries have not been tested, or, which is the case with cranking batteries, were never designed for long Cycle Life.

How to store and maintenance your battery?

All lead acid batteries experience self-discharge in open circuit. The result is that the voltage of open circuit is decreased, and the capacity also decreased. During storage please note:

The self-discharge rate is related with ambient temperature. The self-discharge degree is smaller when the ambient temperature is lower, otherwise is larger.

The requirement temperature of IBT battery storage environment is from 0℃ to 35℃. The storage place must be clean, ventilated and dry. An important parameter in storage is open circuit voltage, which is related with density of the electrolyte. In order to avoid permanent damage to the plate caused by self-discharge, the batteries should be supplementary charged if they have been stored for three months. The equalization charge method should be adopted.

During storage, if the open circuit voltage is lower than 2.10V/Cell, the batteries should be supplementary charged before use. The equalization charge method should be adopted.

All batteries, which are ready to store, should be fully charged before storage. It is suggested record the storage time in the periodic maintenance record and record the time when another necessary supplementary charge should be made.

The quality certificates of IBT batteries record the latest charge time of the batteries, next charge time can be calculated according to this charge time.

In order to assure service life, the batteries should be correctly inspected and maintained. The maintenance methods of IBT batteries are recommended as follows:Monthly Maintenance Implement the under-mentioned inspection every month:Keep the battery-room clean.Measure and record the ambient temperature of the battery-room.Check cleanness of each battery; Check damage and overheating trace of the terminal, container and lid.Measure and record the total voltage and floating current of the battery system.

Quarterly MaintenanceRepeat monthly inspection.Measure and record floating voltage of every on-line battery. If more than two cells voltage is less than 2.18V after temperature adjustment, the batteries need to be equalization charged. If the problem still exists after adopting above-mentioned measures, the batteries need yearly maintenance or even three years maintenance. If all methods are ineffective, please contact us.

Yearly MaintenanceRepeat quarterly maintenance and inspection.Check whether connectors are loose or not every year.Make a discharge test to check with exact load every year, discharging 30-40% of rated capacity.

Three-year MaintenanceMake a capacity test every three years and every year after six years operation. If the capacity of the battery decreases to lower than 80% of rated capacity, the battery should be replaced.

How do VRLA batteries recharge?

While our VRLA batteries accept a charge extremely well due to their low internal resistance, any battery will be damaged by continual under-or overcharging. Capacity is reduced and life is shortened.

Overcharging is especially harmful to any VRLA battery because of the sealed design. Overcharging dries out the electrolyte by driving the oxygen and hydrogen out of the battery through the pressure relief valves. Performance and life are deduced.

If a battery is continually undercharged, a power-robbing layer of sulfate will build up on the positive plate, which acts as a barrier to recharging. Premature plate shedding can also occur. Performance is reduced and life is shortened.

Therefore, it is critical that a charger be used that limits voltage. The charger must be temperature-compensated to prevent under or over discharging due to ambient temperature changes.

Does overcharging damage batteries?

Overcharging is the most destructive element in battery service. Usually the boater is not aware that this is occurring as he believes his alternator or battery charger is "automatic." Unfortunately, these automatic circuits are sensitive to voltage surges, heat, direct lightening strikes and indirect lightening electromagnetic influences and could fail or shift their calibration. When they fail, overcharging begins to affect the batteries. During overcharging, excessive current causes the oxides on the plates of the battery to "shed" and precipitate to the bottom of the cell and also heat the battery, thus removing water from the electrolyte. Once removed, this material (which represents capacity) is no longer active in the battery. In addition, the loss of water from the electrolyte may expose portions of the plates and cause the exposed areas to oxidize and become inactive, thus reducing additional capacity. Sealed batteries are not immune from the same internal results when overcharged. In fact, sealed recombination absorption and gel batteries are particularly sensitive to overcharging. Once moisture is removed from the battery, it cannot be replaced. Portions of the battery damaged due to overcharging are irretrievable. However, if detected early, corrective adjustments to the charging device will save the undamaged portion of the battery. Initial signs of overcharging are excessive usage of water in the battery, continuously warm batteries, or higher than normal battery voltages while under the influence of the charger. If overcharging is suspected, correct immediately.

Does over-discharging damage batteries?

OVERDISCHARGING 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. @ 2.4 to 2.5 volts per cell until 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 and their 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 have been fully charged. Battery chargers are of three types. There is the manual type, the trickle type, and the automatic switcher type.

What determines the life of a VRLA battery?

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).

Battery Installation

Series connectionA series system increases the voltage, but keeps the battery capacity the same. Therefore, two 12-volt batteries connected in series (POS to NEG, NEG to POS) will deliver 24 volts at the same rating as one battery. During recharge, each battery receives the same amount of current; e.g. if the charger is putting out 10 amps, both batteries are getting 10 amps.


Parallel connectionA parallel system increases the capacity available, but keeps the voltage the same. Therefore, two 12-volts, 400 CCA, 110 R.C. and 65 AH will deliver 12 volts, 800 CCA, 220 R.C. and 130 AH.


During recharge, the current is split between the batteries. The battery that is discharged the most will receive more current than the other until both are brought up to full charge.

Series/Parallel ConnectionA series/parallel system provides a combination of voltage and capacity for special applications.Note: Never mix different types and size of batteries in the same bank.

What is the shelf life of a VRLA battery?

All sealed lead acid batteries self-discharge. If the capacity loss due to self-discharge is not compensated for by recharging, the battery capacity may become unrecoverable. Temperature also plays a role in determining the shelf life of a battery. When batteries are stored in areas where the ambient temperature varies, self-discharge can be greatly increased. Check the batteries every three months or so and charge if necessary.

06/16/2009 -- 06/19/2009
Communic Asia, 2009 Singapore
04/13/2009 -- 04/16/2009
Consumer Electronics Moscow 2009
Superior Customer Service

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