1) How do I select the right battery for my application?
Proper battery selection may require the assistance of a knowledgeable battery sales/service technician. Please contact your local Luminous Battery distributor or SMS 'Luminous' to 6161 and our technical experts will contact you.
2) What is the difference between a deep cycle battery and starting battery?
A deep cycle battery has the ability to be deeply discharged and charged many times during its service life. It is designed specifically for powering electrical equipment for long periods of time. An automotive or starting battery is designed for brief bursts of high current and cannot withstand more than a few deep discharges before failure. A tubular positive plate battery is an ultra deep cycle battery. It provides more than double the life of a typical thick flat deep cycle battery.
3) Can I use my Deep Cycle battery as a starting battery?
Deep cycle batteries can be used for engine starting but starting batteries should not be used for deep cycle applications. A deep cycle battery may have less cranking amps per Kg than a starting battery and thus may have to be oversized by about 10% to 20% but in most cases a deep cycle battery is still more than adequate for the purpose of starting an engine.
4) What are the advantages and disadvantages of , AGM, and flooded lead acid deep cycle?
Generally AGM batteries have about 20% less capacity, cost about two times more, and have a shorter cycle life than comparable flooded lead acid batteries. However, AGM batteries do not need watering, are safer (no acid spilling out), can be placed in a variety of positions, have a slower self-discharge characteristic, and are more efficient in charging and discharging than flooded batteries (see table below). Tubular and flat plate deep cycle batteries are more suitable for applications whereas AGM batteries are more for light cycling applications where power cut duration are low.
Flodded
AGM
Charge/Discharge Efficiency
93%
99%
Self discharge rate (per month)
7%
1-3%
Finish Voltage
15.3-16.0V
14.1-14.4V
Float charge
13.2-13.7V
13.4-13.8V
5) What's better? A high or Low D.C voltage system?
Higher-voltage systems tend to be more efficient and put a lower load on the batteries. Factors other than the battery enter into the system's overall efficiency.
6) How does temperature affect the performance of my batteries?
At higher temperatures (above 27oC) battery capacity generally increases, usually at the cost of battery life. Higher temperatures also increase the self-discharge characteristic. Colder temperatures (below 27oC) will lower battery capacity and prolong battery life. Cooler temperatures will slow self-discharge. Therefore, operating batteries at temperatures at or slightly below 27oC will optimize both performance and life.
7) How do I determine my battery capacity when it is colder / hotter?
Battery capacity is basically a linear relationship. A good rule of thumb is that for every 1oC above 27oC, capacity is increased by 0.5% and for every 1oC below 27oC; capacity is reduced by 0.5% rated battery.
8) How do I account for temperature when taking my gravity readings?
Temperature will affect specific gravity readings. As temperature increases, the electrolyte solution expands and as temperature decreases the electrolyte solution contracts. As a result, it is a good practice to temperature correct specific gravity readings. Here is the relationship Luminous recommends using:
For every ten degrees above 27oC add 7 points to the hydrometer reading.
9) How do I account for temperature when taking my voltage readings?
Temperature will affect voltage readings. As temperature increases, voltage decreases. Conversely, as temperature decreases, voltage increases. Here are the relationship Luminous recommends using:
For every 5 degrees C below 27oC, add .028 volt per cell to the charger voltage setting.
10) Is there a maximum temperature for charging my batteries?
When charging lead acid batteries, the temperature should not exceed 52oC intermittently or 45oC. At this point the battery should be taken off charge and allowed to cool before resuming the charge process.
11) When should I water my batteries?
Water is lost during charging. Therefore, the best time to water your batteries is always at the end of the charge cycle. However, if the electrolyte level is extremely low or the plates are exposed to air, add some water to cover the plates before starting the charge cycle. After addition of water, continue change at a low rate for some more time to allow electrolyte mixing.
12) How often should I water my batteries?
How often you discharge and recharge your batteries will determine the frequency of watering. Also using batteries in a hot climate may require more frequent watering. It is best to check your new batteries regularly as this will give you a good feel for how often your application will require battery watering. WARNING: A brand new battery may have a low electrolyte level. Charge the battery first and then add water if needed. Adding water to a battery before charging may result in overflow of the electrolyte.
13) What is the proper electrolyte level?
Liquid levels should be 1/8 inch below the bottom of the vent well (the plastic tube that extends into the battery). The electrolyte level should not drop below the top edge of the plates.
14) Do you ever add acid to a battery?
Under normal operating conditions, you never need to add acid. Only distilled, deionized or approved water should be added to achieve the recommended levels mentioned above. When a battery is shipped in a dry state or accidental spillage occurs, electrolyte should be added to the battery. Once filled, a battery should only need periodic water addition. *Do not over tighten terminals. Doing so can result in post breakage, post meltdown, and fire.
15) Can a battery freeze?
The only way that a battery can freeze is if it is left in a state of partial or complete discharged. As the state of charge in a battery decreases, the electrolyte becomes more like water and the freezing temperature increases. The freezing temperature of the electrolyte in a fully charged battery is -68.88oF. At a 40% state of charge, electrolyte will freeze if the temperature reaches approximately -8.88oF.
16) What is the specific gravity of a fully charged battery?
A hydrometer reading of 1.250 or greater indicates full charge for luminous batteries. This value is based upon a specified temperature of 77 to 80oF. For temperature correction values, see the "Temperature" section of this FAQ.
17) What are common mistakes made by lead acid battery owners?
Undercharging: Generally caused by not allowing the charger to restore the battery to full state of charge after use. Continually operating the battery in a partial state of charge, or storing the battery in discharged state results in the formation of lead sulfate compounds on the plates. This condition is known as sulfation. Both of these conditions reduce the battery's performance and may cause premature battery failure. Undercharging will also cause stratification. Overcharging: Continuous charging causes accelerated corrosion of the positive plates, excessive water consumption, and in some cases, damaging temperatures within a lead acid battery. Deep cycle batteries should be charged after each discharge of more than 50% of the batteries rated capacity, and/or after prolonged storage of 45 days or more. Under watering: In deep cycle, lead acid batteries water is lost during the charging process. If the electrolyte level drops below the tops of the plates, irreparable damage may occur. Water levels should be checked and maintained routinely. Over-watering: Excessive watering of a battery results in additional dilution of the electrolyte, resulting in reduced battery performance. Additionally, watering the battery before charging may result in electrolyte overflow and unnecessary additional maintenance.
18) Can I reduce my maintenance by not gassing my batteries?
You will reduce the frequency of watering, but will cause a condition known as stratification where the specific gravity of the electrolyte is light at the top of the battery and heavy at the bottom. This condition results in poor performance and reduced battery life. The higher concentration of electrolyte at the bottom causes heavy sulfation on the bottom part of the plates. The lower concentration of the electrolyte at the top causes hydration at the top part of the plates.
19) How can I tell if a battery is bad?
To determine if the battery system is experiencing a problem, fully charge the batteries then shut off the charger and remove all electrical loads. Allow each battery in the system to stand on open-circuit for about one hour. Measure the voltage of each battery. If the battery voltage spread exceeds .30 volts for a 12 volt battery, a problem is indicated. Battery voltage alone does not confirm a problem. When the voltage spread indicates a problem, confirmation is accomplished by taking electrolyte specific gravity readings using a hydrometer. If the specific gravity readings show a spread greater than .030 (30 points), give the batteries equalization charge i.e slow constant current charge @ 3% of the battery capacity in amperes.
