1.What is a Sealed Maintenance Free Battery?

Sealed batteries are known as maintenance free batteries. They are made with vents that (usually) cannot be removed. A standard auto or marine maintenance free battery is sealed, but not fully leak proof. Sealed batteries are not totally sealed since all batteries must allow gas to vent during charging. There are sealed lead acid (SLA) batteries that are non-spillable. Please read the information on our SLA batteries, see AGM and Gel batteries below.

2.What are major types of lead acid batteries?

Batteries are divided in two ways, by application (what they are used for) and construction (how they are built). The major applications are automotive, marine, and deep-cycle. Deep-cycle includes solar electric (PV), backup power, and RV and boat "house" batteries. The major construction types are flooded (wet), gelled, and AGM (Absorbed Glass Mat). AGM batteries are also sometimes called "starved electrolyte" or "dry", because the fiberglass mat is only 95% saturated with Sulfuric acid and there is no excess liquid. Flooded may be standard, with removable caps, or the so-called "maintenance free" (that means they are designed to die one week after the warranty runs out). All gelled are sealed and a few are "valve regulated", which means that a tiny valve keeps a slight positive pressure. Nearly all AGM batteries are sealed valve regulated (commonly referred to as "VRLA" - Valve Regulated Lead-Acid). Most valve regulated are under some pressure - 1 to 4 psi at sea level

3.What are deep cycle batteries?

Deep-cycle batteries typically feature thick plates with a high-density active material. The thick battery plates allow for reserve energy to be stored deep within the battery plate and released during slow discharge such as trolling or electronic instrument use. The high-density active material remains within the batteries' plate/grid structure longer, resisting the normal degradation found in cycling conditions. They are typically used where the battery is discharged to great extent and then recharged such as a battery powered trolling motor on a fishing boat

4.What are the advantages of the AGM battery?

The advantages of AGM batteries are no maintenance, sealed against fumes, hydrogen, leakage, or non-spilling even if they are broken, and can survive most freezes. AGM batteries are "recombinant" – which means the Oxygen and Hydrogen recombine inside the battery. These use gas phase transfer of oxygen to the negative plates to recombine them back into water while charging and prevent the loss of water through electrolysis. The recombining is typically 99+% efficient, so almost no water is lost. Charging voltages for most AGM batteries are the same as for a standard type battery so there is no need for special charging adjustments or problems with incompatible chargers or charge controls. Since the internal resistance is extremely low, there is almost no heating of the battery even under heavy charge and discharge currents. AGM batteries have a very low self-discharge rate (from 1% to 3% per month). So they can sit in storage for much longer periods without charging. The plates in AGM's are tightly packed and rigidly mounted, and will withstand shock and vibration better than any standard battery.

 

5.Battery Storage, Care & Maintenance

The Storage or shelf life of a VRLA battery is usually between 12 and 18 months at 20 degree starting From a charged condition.
Warning :
Never store in a discharged or partially discharged state.
Always store in a dry, clean, cool environment in a fully packaged condition.
If storage of 12 months or longer is required supplementary charging will be require

Battery Care
Each BSB VRLA battery is supplied I a charged condition having passed stringent quality checks.To ensure optimum battery performance and life, it helps to take care of your battery by observing the following:

Sulphation/Undercharge
Warning – Never leave a VRLA Battery in a discharged state.
If a battery has an open-circuit voltage lower than its rated value, then sulphation may well be the cause.
When a battery is left a discharged state or for prolonged periods of storage, lead sulphate crystals begin to form acting as a barrier to recharge and will prevent normal battery operation.
Depending on the degree of sulphation, battery may be recovered from this condition by constant current charging at a higher voltage with the current limited to one tenth of the battery capacity for a maximum of 12 hours.

Note: The applied voltage will exceed the normal recommendation and so the battery must be monitored (not left unattended) and removed from charge if excess heat is dissipated. The voltage required to «force» this maximum current into the battery will reduce as the battery recovers until normal charging can take place.

In extreme circumstances a battery may never fully recover from sulphation and must therefore be replaced.

Overcharge
As mentioned in Section 4 optimum charging relies mainly on voltage, current and temperature factors which are interrelated and all of which can cause overcharge.
Excessive charge voltages will force a high overcharge current into the battery, which will dissipate as heat, and may cause gas emission through the safety valve. Within a short period of time this will corrode the positive plate material and accelerate the battery towards end-of-life.

Under these conditions the heat produced inside the battery can lead to thermal runaway due to the increased electrochemical reaction within the battery. The battery may swell before failing and will be irrecoverable from this state. This situation is potentially dangerous.

Temperature
Warning – Heat Kills Batteries.
The recommended normal operating temperature is 20°C.
HIGH TEMPERATURE will reduce battery service life often quite dramatically. In extreme cases this can cause Thermal Runaway, resulting in high oxygen/hydrogen gas production and battery swelling. Batteries are irrecoverable from this condition and should be replaced.

 

6.How to connect a battery in Parallel?

The positive terminal of the first battery is connected to the positive terminal of the second battery, the positive terminal of the second is connected to the positive of the third, etc. and The negative terminal of the first battery is connected to the negative terminal of the second battery, the negative terminal of the second is connected to the negative of the third, etc. So the batteries are connected: + to + to + and - to - to -. In this configuration, the capacity is the sum of the capacities of the individual batteries and voltage is unchanged. For example, if you take 5 6V 10AH batteries and connect the batteries in series, you would end up with a battery array that is 30 Volts and 10AH. If you connect the batteries in parallel, you would end up with a battery array that is 6 Volts and 50AH. By the way, this is how ordinary auto batteries are made. 6 2volt cells are put in series to give 12v battery and the 6 cells are just enclosed in one case. Many ni-cad batteries are done the same way.

 

7.  What is the difference between SLA, VRLA and AGM batteries?

SLA and VRLA are different acronyms for the same battery, Sealed Lead Acid or Valve Regulated Lead Acid. This battery type has the following characteristics: Maintenance-free, leak-proof, position insensitive. Batteries of this kind have a safety vent to release gas in case of excessive internal pressure build up. AGM, Absorbed Glass Mat refers to a specific type of SLA/VRLA where the electrolyte is absorbed into separators between the plates consisting of sponge like fine glass fiber mats.

 

8.AGM and Gel Cell Batteries Difference?

Both types of batteries are sealed, valve regulated batteries allowing them to be used in any position. The difference lies in the way the electrolyte is immobilized. In case of AGM (absorbed glass mat), the newer of the two technologies, the electrolyte is absorbed by the glass fiber separator who acts like a sponge. In a gel-type battery the liquid electrolyte turns into a gel right after the battery is filled. Gel batteries use a different type of separators which are not absorbent. Because of the design, gel cell batteries don't offer the same power capacity as do the same physical size AGM battery. For example, an AGM battery that is 12V 100AH, whereas, for example, a gel cell battery in the same size case would only be rated at 84AH.However, the Gel Cell excels in slow discharge rates and slightly higher operating temperatures. The internal design is otherwise similar.

 

9.What is the difference between cycle use and standby use?

When a battery is being used as a power source on a regular basis and it is being discharged and subsequently recharged, the battery is said to be in cyclic use. The determining factor in the life of this battery is the number of charge/discharge cycles that can be completed. In cyclical applications up to 1,000 charge/discharge cycles can be expected depending on the average depth of discharge.

Standby batteries are meant to act as an emergency power source where the main power source has failed for some reason. Consequently standby batteries are kept fully charged so that they can “kick in” immediately. The batteries remain connected to a trickle charger that will keep the battery fully charged and ready for use. In standby use the batteries have a design life of up to five years. Please consult our technicians for more details.

10.SLA, VLRA, AGM, Is There a Difference?

SLA (Sealed Lead Acid) and VRLA (Valve Regulated Lead Acid) are different acronyms for the same battery. This battery type has the following characteristics: Maintenance-free, leak-proof, position insensitive. Batteries of this kind have a safety vent to release gas in case of excessive internal pressure build up. AGM (Absorbed Glass Mat) refers to a specific type of SLA/VRLA where the electrolyte is absorbed into separators between the plates consisting of sponge like fine glass fiber mats. SLA batteries are divided up into specific subsets of batteries.

 

11.Is it possible to increase the DC voltage and capacity (Ah) by connecting VRLA batteries 

Voltage can be increased by connecting the positive terminal of one battery to the negative terminal of an adjacent battery. Therefore, connecting four 12V 7Ah batteries together in this manner will effectively raise the voltage across the battery from 12 to 48V. Battery capacity will remain at 7Ah. This is commonly termed ‘series’ connection. Capacity can be increased by connecting the positive terminal of one battery to the positive battery of the next. Negative terminals could be connected together in a similar manner. Therefore, connecting four 12V 7Ah batteries will effectively raise the capacity available across the batteries from 7 to 28Ah. Battery voltage will remain at 12V. This is commonly termed ‘parallel’ connection.

The connection of the batteries in series and parallel will increase both capacity and voltage. Note. It is recommended that consultation with the battery manufacturer be made before connecting “mixed” product types in series or parallel.

 

12.What does the term 20-hour and 10-hour mean?

Battery manufacturers rate capacities (Ah) against specific times (hours) to a specified end of discharge voltage. For example, a THUNDER POWER product is rated at the 20-hour rate. Therefore, the NP7-12 VRLA battery will support a constant load of approximately 350mA (7/20) for 20 hours to an end voltage of 1.75V per cell (VPC). It will not support a constant load of 7A per hour for 20 hours. Discharging the battery over one hour will reduce the efficiency of the battery to approximately 60% of the battery’s rated capacity (4.2Ah in the case of a 7Ah battery) and will therefore support a constant load of 4200mA for this period.

Battery manufacturers often publish data that refers to the ‘C’ or ‘CA’ rates. Discharge curves being a typical example. Both terms refer to current (Amps) in relation to the capacity (C) of the battery. Therefore, for a Yuasa NP7-12 battery ‘2C’ equates to a current of 14A (2 x 7) and ‘1C’ or ‘C’ for the same battery relates to 7 Amps etc.

 

13. How can I do a simple battery sizing?

To carry out the most basic battery sizing for a portable tool for example, you must establish: (a) DC output voltage of the tool i.e. 6, 12, 24V etc. (b) load (amps) of the tool and (c) length of time (autonomy) the tool needs to be supported by the battery i.e. battery back up time. Note. If the tool is rated in watts, simply convert to amps by dividing the watts by the nominal voltage of the equipment. Determine if there are any physical constraints that may affect your selection, such as: application; environmental; temperature or dimensional restraints. Then, using Figure 1, which denotes a series of graphs based on time against current (amps) for a selection of Yuasa NP batteries, a battery selection can be made. NB. Battery sizes are normally calculated in the UK based on an ambient temperature of 20 to 25°C. At higher temperatures, the capacity of a battery increases while life expectancy decreases and, conversely, at lower temperatures, the capacity decreases.

 

14. Can the battery add distilled water?

Valve-regulated sealed maintenance-free lead-acid battery is different with other batteries. In fact, though less evaporation of the electrolyte and no leakage, the battery still needs a little bit maintenance work. Because the charging equipment do not reach the ideal level yet, it is inevitable that there are small amount of evaporation of distilled water. For those who know a little about the battery knowledge, if find the capacity decreased above, they could add some water in moderation to recover the concentration of electrolyte. A little bit lower concentration is also okay. Those activities are good for the plates.

 

15. 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 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. Sulfate occurs when sulfur from the electrolyte combines with the lead on the plates and forms lead-sulfate. Once this condition becomes occurs, marine battery chargers will not remove the hardened sulfate. Sulfate 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 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 then 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 have been fully charged. Battery chargers are of three types. There is the manual type, the trickle type, and the automatic switcher type.