Construction of the battery:

The manufacturing process begins with the production of a plastic container and cover. Most automotive battery containers and their covers are made of polypropylene. A 12-volt lead-acid battery is made up of six energy producing unit called cells. The cover is dropped on and sealed when the battery is finished.

(1) A resilient plastic (polypropylene) container. (2) Positive and negative internal plates made of lead. (3) Plate separators made of porous synthetic material. (4) Electrolyte, a dilute solution of sulfuric acid (H2SO4) and water (H2O), better known as battery acid. (5) Lead terminals, the connection point between the battery and whatever it powers.

The process continues with the manufacture of grids from lead or an alloy of lead and other metals. A battery must have positive and negative plates to conduct a charge. Next, a paste mixture of lead oxide (PbO2) -- which is powdered lead and other materials -- sulfuric acid and water is applied to the grids. Expander material made of powdered sulfates is added to the paste to produce negative plates.

Inside the battery, the pasted positive and negative plates must be separated to prevent short circuits. Separators are thin sheets of porous, insulating material used as spacers between the positive and negative plates. Fine pores in the separators allow electrical current to flow between the plates while preventing short circuits. In the next step, positive plates are paired with negative plates and separators. This unit is called an element, and there is one element per battery cell, or compartment in the container. Elements are dropped into the cells in the battery case. The cells are connected with a metal that conducts electricity. The lead terminals, or posts, are then welded on. The battery is then filled with electrolyte - or battery acid -- a mixture of sulfuric acid and water, and the cover is attached. The battery is checked for leaks. The final step is formation. During this step, the battery terminals are connected to a source of electricity and the battery is charged for many hours. When the battery is fully formed, it moves to another line where the case is cleaned, if necessary, and the labels are attached. Each cell of the 12-volt lead-acid battery has 2 sets of electrodes. They are made of 8 overlapping metallic plates for a total 16 per cell. Together the plates form a compact grip. The positive grip cover in lead oxide carries electrons in. The negative grip cover in lead releases electrons. The plates soak in the chemical bath consisting of 65% water and 35% sulfuric acid. The bath of water and sulfuric acid creates electrolyte, the substance that conducts electricity. As the battery discharges or unloads electricity, the acid bath

reacts to the chemicals on the plates. Tipping them in the electrolyte bath releases particles called electrons. When they start racing in the grids, they create electricity. The main active materials required to construct a lead – acid battery are: Lead Peroxide (PbO2) – positive plate This is dark brown, hard and brittle substance. Lead dioxide PbO2, metal (lead) oxide is, basically, a ceramic substance with ceramic-like mechanical properties. It is hard, sensitive to impact (easily breakable) and consists of small microscopic-sized fragments, glued to each other with a special binder at the time of the positive plate manufacture. In case of wrong manipulation with the accumulator, i.e., if exposed to shaking, the positive plate is being damaged. During charging and discharging, the positive plate volume (its chemical composition) is being changed, which unfavourably affects the positive plate integrity (individual PbO2 particles are being gradually unglued from each other). Similar effects are caused by charging at high current, when the positive plate is being locally overheated (at places of the high current flow) and individual material particles are being unglued. Sponge Lead (Pb) – negative plate The negative plate is made of pure lead in soft sponge condition. Lead (Pb), metal is pliable and highly resistant to mechanical stress (it changes its shape under pressure): However, the plate is produced in such a manner that it contains a lot of pores. If batteries are used incorrectly (overheating, high concentration of electrolyte – sulfuric acid), etc., metal pliability is shown and pores cease to exist. The plate surface area is being thereby reduced. Since the battery capacity is directly proportional to the surface area of electrodes, it is right the capacity that is being thereby reduced. Thus, in order to keep the battery capacity, it is necessary to preserve the negative plate porosity Dilute Sulfuric Acid (H2SO4) Dilute Sulfuric Acid used for lead acid battery has ration of water : acid = 3:1. The electrolyte is sulfuric acid with the density of 1.28g/cm3 or, in other words, with the concentration of 38%. Sulfuric acid in this concentration is quite a strong alkali; therefore, it is necessary to observe strict safety regulations when working with batteries. Sulfuric acid for batteries is produced in a special way (other than ordinary industrial sulfuric acid), in order not to contain impurities, especially iron and nitrogen, as both of these elements damage batteries. The lead acid storage battery is formed by dipping lead peroxide plate and sponge lead plate in dilute sulfuric acid. A load is

connected externally between these plates. In diluted sulfuric acid the molecules of the acid split into positive hydrogen ions ( H+) and negative sulfate ions (SO4

− −). The hydrogen ions when reach at PbO2 plate, they receive electrons from it and become hydrogen atom which again attack PbO2 and form PbO and H2O (water). This PbO reacts with H2 SO4 and forms PbSO4 and H2O (water). Plates:

Faure pasted-plate construction is typical of automotive batteries. Each plate consists of a rectangular lead grid alloyed with antimony or calcium to improve the mechanical characteristics. The holes of the grid are filled with a paste of red lead (Pb3O4) or litharge (PbO) or the mixture of two in various proportions and 33% dilute sulfuric acid. (Different manufacturers vary the mixture). The paste is pressed into the holes in the grid which are slightly tapered on both sides to better retain the paste. This porous paste allows the acid to react with the lead inside the plate, increasing the surface area many fold. Once dry and hardened, the plates are stacked with suitable separators and inserted in the battery container. An odd number of plates is usually used, with one more negative plate than positive. Each alternate plate is connected. The positive plates are the chocolate brown color of lead dioxide, and the negative are the slate gray of "spongy" lead at the time of manufacture. In this charged state the plates are called 'formed'.

One of the problems with the plates is that the plates increase in size as the active material absorbs sulfate from the acid during discharge, and decrease as they give up the sulfate during charging. This causes the plates to gradually shed the paste. It is important that there is room underneath the plates to catch this shed material. If it reaches the plates, the cell short-circuits.

Practical cells are usually not made with pure lead but have small amounts of antimony, tin, calcium or selenium alloyed in the plate material to add strength and simplify manufacture. The alloying element has a great effect on the life of the batteries, with calcium-alloyed plates preferred over antimony for longer life and less water consumption on each charge/discharge cycle. About 60% of the weight of an automotive-type lead–acid battery rated around 60 Ah (8.7 kg of a 14.5 kg battery) is lead or internal parts made of lead; the balance is electrolyte, separators, and the case. Separators:

Separators between the positive and negative plates prevent short-circuit through physical contact, mostly through dendrites (‘treeing’), but also through shedding of the active material. Separators obstruct the flow of ions between the plates and increase the internal resistance of the cell. Wood, rubber, glass fiber mat, cellulose, and PVC or polyethylene plastic have been used to make separators. Wood was the original choice, but deteriorated in the acid electrolyte. Rubber separators were stable in the battery acid. An effective separator must possess a number of mechanical properties; such as permeability, porosity, pore size distribution, specific surface area, mechanical design and strength, electrical resistance, ionic conductivity, and chemical compatibility with the electrolyte. In service, the separator must have good resistance to acid and oxidation. The area of the separator must be a little larger than the area of the plates to prevent material shorting between the plates. The separators must remain stable over the battery's operating temperature range. Electrochemistry

Discharge

In the discharged state both the positive and negative plates become lead (II) sulfate (PbSO4) and the electrolyte loses much of its dissolved sulfuric acid and becomes primarily water. The discharge process is driven by the conduction of electrons from the negative plate back into the cell at the positive plate in the external circuit. Negative plate reaction (Anode Reaction):

Charged sulfate ion approaches uncharged Lead atom becomes ionized and froms ionic bond with sulfate ion.

Lead atom on surface of electrode Two electrons are released into lead electrode This reaction releases net energy 0.356eV Positive plate reaction (Cathode Reaction):

Charged sulfate and hydrogen ions approach Lead atom changes ionization and forms ionic bond with sulfate ion. lead-dioxide molecule on surface of electrode Two water molecules are released into solution. This reaction releases net energy 1.685eV The total reaction can be written: Pb(s) + PbO2(s) + 2H2SO4(aq) → 2PbSO4(s) + 2H2O(l) The whole reaction releases net energy 1.685eV + 0.356eV = 2.041eV

SO4 − − ions are moving freely in the solution so some of them will reach to pure Pb plate where they give their extra electrons and become radical SO4. As the radical SO4 cannot exist alone it will attack Pb and will form PbSO4 As H+ ions take electrons from PbO2 plate and SO4 − − ions give electrons to Pb plate, there would be an inequality of electrons between these two plates. Hence there would be a flow of current through the external load between these plates for balancing this inequality of electrons. This process is called discharging of lead acid battery The lead sulfate (PbSO4) is whitish in color. During discharging:

1. Both of the plates are covered with PbSO4, 2. Specific gravity of sulfuric acid solution falls due to formation of water during reaction at PbO2 plate. 3. As a result, the rate of reaction falls which implies the potential difference between the plates decreases during

discharging process.

Charging

Fully Charged: Lead and Lead Oxide plates In the charged state, each cell contains negative plates of elemental lead (Pb) and positive plates of lead(IV) oxide (PbO2) in an electrolyte of approximately 33.5% v/v (4.2 Molar) sulfuric acid (H2SO4). The charging process is driven by the forcible removal of electrons from the positive plate and the forcible introduction of them to the negative plate by the charging source. Negative plate reaction: PbSO4(s) + H+(aq) + 2-e → Pb(s) + HSO−4(aq) Positive plate reaction: PbSO4(s) + 2H2O(l) → PbO2(s) + HSO−4(aq) + 3H+(aq) + 2-e By charging the lead acid storage battery cell:

1. Lead sulfate anode gets converted into lead peroxide 2. Lead sulfate of cathode is converted to pure lead 3. Terminal; potential of the cell increases 4. Specific gravity of sulfuric acid increases

Voltage versus electrolyte concentration

By exceeding the charging voltage 14.7 V water starts decompose into oxygen and hydrogen, the battery begins to "bubble" – called as well as gassing.

Measurement of the state-of-CHARGE The battery's electrolyte temperature cannot be above 43.3° C. To determine the battery's state-of-charge with the battery's electrolyte temperature at 26.7° C, the table below must be used. The table assumes that a 1.265 specific gravity reading is a fully charged, wet, lead-acid battery. For other electrolyte temperatures, the Temperature Compensation table below must be used to adjust the Open Circuit Voltage or Specific Gravity readings.

Digital Voltmeter Open Circuit Voltage

Approximate State-of-Charge

Hydrometer Average Cell Specific Gravity

Electrolyte Freeze Point

12.65 100% 1.265 -59.4° C

12.45 75% 1.225 -48.3° C

12.24 50% 1.190 -36.7° C

12.06 25% 1.155 -26.7° C

11.89 Discharged 1.120 -23.3° C

State of CHARGE

Electrolyte Temperature Celsius

Add or Subtract to Hydrometer's SG Reading

Add or Subtract to Digital Voltmeter's Reading

43.3° +.012 +.072

37.8° +.008 +.048

32.2° +.004 +.024

26.7° 0 0

21.1° -.004 -.024

15.6° -.008 -.048

10° -.012 -.072

4.4° -.016 -.096

-1.1° -.020 -.120

-6.7° -.024 -.144

-12.2° -.028 -.168

-17.8° -.032 -.192

Temperature Compensation Electrolyte temperature compensation, depending on the battery manufacturer's recommendations, will vary. If you are using a non-temperature compensated HYDROMETER, make the adjustments indicated in the table above. For example, at -1.1° C, the specific gravity reading would be 1.245 for a 100% State-of-Charge. At 37.8°C, the specific gravity would be 1.273 for 100% State-of- Charge. This is why using a temperature compensated hydrometer is highly recommended and more accurate. If you are using a DIGITAL VOLTMETER, make the adjustments indicated in the table above. For example, at -1.1° C, the voltage reading would be 12.53 for a 100% State-of-Charge. At 37.8° C, the voltage would be 12.698 for 100% State-of-Charge. For non-sealed batteries, check the specific gravity in each cell with a hydrometer and average cells readings. This is the only way you can determine the State-of-Charge. Some batteries have a built-in hydrometer, which only measures the State-of-Charge in ONE of its six cells. If the built-in indicator is clear, light yellow, or red, then the battery has a low electrolyte level and if non-sealed, should be refilled and recharged before proceeding. If the State-of-Charge is BELOW 75% using either the specific gravity or voltage test or the built-in hydrometer indicates “bad” (usually dark or white), then the battery needs to be recharged BEFORE proceeding. How do I test Battery?

Inspect Visually inspect for obvious problems such as a loose or broken alternator belt, low electrolyte levels, dirty or wet battery top, corroded or swollen cables, corroded terminals or battery posts, loose hold-down clamps, loose cable terminals, or a leaking or damaged battery case. If the electrolyte levels are low, allow the battery to cool and add only distilled water to the level indicated by the battery manufacturer or to between 3 to 7 mm below the bottom of the plastic filler tube (vent wells). The plates need to be covered at all times. Avoid overfilling, especially in hot climates, because heat will cause the electrolyte to expand and overflow.

When is the time to replace the battery

It is generally recommended to replace the battery, if one or more of the following conditions occur:

1. If there is a .050 (sometimes expressed as 50 “points”) or more difference in the specific gravity reading between the highest and lowest cell, you have a weak or dead cell(s). Applying an EQUALIZING charge may correct this condition.

2. If the battery will not recharge to a 75% or more State-of-Charge level or if the built-in hydrometer still does not indicate “good” (usually green or blue, which indicates a 65% State-of-Charge or better).

3. If you know that a battery has spilled or “bubbled over” and the electrolyte has been partially replaced with water, you can replace this old electrolyte with new electrolyte and charge a battery. Battery electrolyte (battery acid) is a mixture of 38% sulfuric acid and distilled water when fully charged. It less expensive to replace the electrolyte than to buy a new battery.

4. If the digital voltmeter indicates 10.45 to 10.65 volts, there probably is a shorted cell. A shorted cell is caused by plates touching, sediment (“mud”) build-up or “treeing” between the plates.

5. If the battery doesn’t pass the Load Test

How to know if the battery is still in good condition If the battery's State-of-Charge is at 75% or higher or has a “good” built-in hydrometer indication, then you can load test the battery by one of the following methods to find out if the battery is still in good condition: With a battery load tester, apply a load equal to three times of the battery capacity or one half of the CCA rating of the battery or for 5 seconds. DURING the load test, the voltage on a good battery will CANNOT drop below the following table's indicated voltage for the electrolyte at the temperatures shown:

Electrolyte Temperature C

Minimum Voltage Under LOAD

37.8° 9.9

32.2° 9.8

26.7° 9.7

21.1° 9.6

15.6° 9.5

10.0° 9.4

4.4° 9.3

-1.1° 9.1

-6.7° 8.9

-12.2° 8.7

-17.8° 8.5

Why do batteries die?

When the active material in the plates can no longer sustain a discharge current, the battery “dies”. Normally a battery “ages” as the active positive plate material sheds (or flakes off) due to the normal expansion and contraction that occurs during the discharge and charge cycles. The positive plate is a ceramic material which is fragile. Particles are glued with a conductive paste during plate mixture sintering. During the conversion of PbO2 into PbSO4, its mass volume changes, which causes small cracks. The bigger the number of charging and discharging cycles is, the higher the number of defects in the material. Unfavourable effects are caused also by a high temperature of the electrode, e.g., as a result of a high current density (high current through unit area), e.g., with a significant sulfation of the electrode. The positive plate looses, due to the high flowing current, its porosity, whereby its surface (to which the battery capacity is directly proportional) is being reduced.This causes a loss of plate capacity and a brown sediment, called sludge or “mud,” that builds up in the bottom of the case and can short the plates of a cell out. In hot climates, additional major causes of failure are positive grid growth, positive grid metal corrosion in the electrolyte, negative grid shrinkage, buckling of plates, or loss of water. Deep discharges, heat, vibration, and over charging accelerate the “aging” process. Major cause of premature battery failure is mostly sulfation. It is caused when a battery's State-of-Charge drops below 100% for long periods or undercharging. Hard lead sulfate fills the pours and coats the plates Sulfation The formation of sulfate is a standard and essential electrochemical phenomenon during the battery discharging, while lead sulfate (sulfate) is formed in the form of a very fine white powder with the sizes which can be Sulfation impedes recharging; sulfate deposits ultimately expand, cracking the plates and destroying the battery. Eventually so much of the battery plate area is unable to supply current that the battery capacity is greatly reduced. In addition, the sulfate portion (of the lead sulfate) is not returned to the electrolyte as sulfuric acid. The large crystals physically block the electrolyte from entering the pores of the plates. Sulfation can be avoided if the battery is fully recharged immediately after a discharge cycle. A white coating on the plates may be visible (in batteries with clear

cases, or after dismantling the battery). Batteries that are sulfated show a high internal resistance and can deliver only a small fraction of normal discharge current. Sulfation also affects the charging cycle, resulting in longer charging times, less efficient and incomplete charging, and higher battery temperatures. An over sulfated cell has high internal resistance and requires extra voltage across the cell, which also causes them to develop higher temperatures on charge and extensive gassing is observable at lower charging voltage! If we notice the "gassing" at a voltage of less than about 14.4 V, it is one of the signals of sulphation of the battery (the lower the voltage, the greater sulfation!).

Recharging a sulfated battery is like trying to wash your hands with gloves on. Using tap water to refill batteries can produce calcium sulfate that can also fill the pores and coat the plates. Can we recover heavily sulphated battery?

YES, by adding PowerBatt! PowerBatt breaks the sulfate crystals by active oxygen released from hydrogen peroxide. Since the

sizes of sulfate particles are significantly reduced, their weight will be sufficiently low in order that individual particles could be entrained by ions in the electrolyte during charging. This phenomenon results in an increase in the concentration of sulfuric acid in the battery in which PowerBatt has been used and which has been subsequently charged. This phenomenon is one of the most direct proofs of the PowerBatt functioning.

Effects of PowerBatt on Lead acid battery

Desulfatization

Hydrogen peroxide eliminates coarse-grained sulphates (that are non-conducting and prevent accumulator charging and discharging). The coarse-grained sulphate elimination takes place by means of elemental oxygen released from hydrogen peroxide, which crushes crystalline sulphate into fine-powdered. This is incorporated during charging into accumulator electrodes, while the sulphuric acid concentration increases. Sulfatization is a natural phenomenon during lead accumulator discharging. There are two types of sulfatization: reversible and irreversible sulfatization. Reversible sulfatization is a part of an electrochemical reaction during accumulator discharging.

PbO2 + Pb + 2H2SO4 = 2PbSO4 + 2H2O,

where PbSO4 is the sulphate itself being formed during discharging. Such sulphate is formed in the form of a very fine powder and forms the electrode surface. Electric current may pass among sulphate grains in the form of ions. The energy of the ions is sufficient for back transformation of such fine-grained sulphate during the accumulator charging, which allows transformation of Pb (on the negative electrode) and PbO2 (on the positive electrode). When we talk about the sulfatization as a negative phenomenon, we thereby mean the irreversible sulfatization. The irreversible sulfatization arises from the fine powder coming from the reversible sulfatization in such a manner that in case of a suitable external environment, the fine powder starts to form bigger clusters and crystals of sulphate. Since the sulphate clusters and crystals are too big compared to the energy of the ions, these remain untouched during charging. These clusters can be partially made smaller by charging the accumulator by small current (1-2% of the accumulator capacity). In this way, however, only fine sulphate grains are released from the surface of the sulphate crystals. The sulphate firmly inbuilt in the crystal remains untouched. Effects of Hydrogen Peroxide: Hydrogen peroxide is a reactive material which, when in contact with most other substances, gradually releases elemental oxygen. Hydrogen peroxide in the liquid state flows into fine pores of the sulphate crystals. By releasing elemental oxygen, having a significantly bigger volume in the gaseous state than that bound in peroxide, de facto breaks sulphate crystals into a fine powder. This powder is, with regard to its fine structure, dispersed in the electrolyte close to its formation, i.e., close to the active mass of the electrodes. During charging, with respect to its size, it is being broken down by the electrolyte ions and gradually incorporated in the active mass of the electrodes. This results in an increased concentration of the electrolyte (sulphuric acid) in the charged state of the accumulator after using PowerBatt and following several charging cycles when compared to the electrolyte concentration in the accumulator charged state before PowerBatt is used. The increased electrolyte concentration results from the reaction of the released SO4 group from crystalline PbSO4, which forms sulphuric acid with released hydrogen during charging.

Sulfated plates are less porous than normal and absorb a charge with difficulty. With this condition, an ordinary charge will not reconvert all the sulfate to sulfuric acid and specific gravity remains below normal. Active material of "over sulfated" negative plates is light in color and either hard and dense or granular and gritty and easily disintegrated.

Grey sponge plates in healthy condition due to regular usage of Powerbatt liquid. No signs of sulfation can be seen on a plate.

Optimization of the Active Mass Morphology The organic dispersing component is able to favourably adjust the morphology of active mass crystals, create a fine film around them and thereby disallow their intergrowth into a coarse-grained structure (which is then one of the consequences of the capacity reduction). In addition, it forms crystallization nuclei, whereby it allows the formation of a favourable fine-grained structure. The proper morphology (spatial organization of the material in the mass) is a very important assumption for the accumulator capacity preservation. It has become evident that the prismatic morphology of the positive electrode favourably affects the active mass quality. The preservation of the active mass morphology requires the creation of suitable conditions (of the energy during the accumulator charging) and an optimum dispersion of the material in the electrolyte in the close proximity of the active mass. The PowerBatt organic component creates optimum dispersion of the material for the preservation of the active mass proper morphology. It at the same time forms a fine film on the active mass surface, which prevents the clustering of the active mass fine-grained material, whereby it preserves its fine-grained structure. The fine-grained structure of the active mass directly affects the size of the electrode surface. Thanks to the dispersion properties of this organic component and its fine structure, there is a formation of a big number of crystallization nuclei. The number of these crystallization nuclei directly determines the number of the newly formed crystals, in which the whole material of the positive mass crystallizes during charging. Since the material quantity is definite, more crystallization nuclei form finer crystallizing structures. The finer structure means a larger effective area and higher capacity of the positive electrode. Acceleration of Diffusion Processes The organic dispersing component is at the same time, with respect to its dispersion properties, able to accelerate diffusion processes in the cell and prevent the formation of acid layers with various densities (the so-called acid stratification). Diffusion processes are the slowest processes in lead accumulators. The speed of such processes is directly responsible for the quantity of the transferred charge in a time unit. The transferred quantity of the charge (number of ions) per unit of time is determined by the serial internal resistance of the accumulator. The PowerBatt organic component accelerates the diffusion processes of the accumulator and thereby increases the quantity of the transferred charge per time unit. This results in a reduction in the serial internal resistance of the accumulator. The accumulator voltage will drop more slowly during discharging thanks to the smaller voltage drop on the internal serial resistance, whereby the quantity of the suppliable energy will increase, which is measurable as an increase in the accumulator capacity. Dispersion properties of the organic component at the same time homogenize the electrolyte and thereby prevent its density stratification in the accumulator. This phenomenon results in a more equal usability of the active mass of the electrodes regardless of whether the given active mass is close to the accumulator bottom or close to the electrolyte level. Increase in Porosity and Strength of Active Mass (Especially Positive) Salts contained in PowerBatt are able to increase the porosity of active masses and at the same time increase their strength. The accumulator capacity directly depends on the size of the electrode active surface. PowerBatt contains salts that increase, during the accumulator charging, its porosity and strength, while preserving its morphology. This effect generally improves mechanical properties of the positive electrode active mass and prevents its early disintegration. Formation of Bridges

The salts in PowerBatt mechanically and electrically join grains of the positive electrode active mass by needle-shaped crystals but at the same time prevent the active mass intergrowth into big crystals, whereby the active area of the electrode would be reduced. The positive electrode is, like ceramic material (PbO2), particularly sensitive to mechanical stresses resulting from local overheating or improper accumulator handling. The salts contained in PowerBatt support the intergrowth of needle-shaped crystals in between grains of the positive active mass, whereby its mechanical strength and electrical conductivity improve. Together with other components, they prevent the active mass intergrowth into big crystals, which would reduce the total area of the active mass grains and thus reduce the energy efficiency of the accumulator too. Formation of Passivation Films The ions contained in PowerBatt favourably affect the charging and discharging voltages and polarizations and at the same time suitably modify conditions on the "active mass/grid" interface (these conditions are often a reason for expiration of the accumulator life) and provide for the formation of passivation films. The grid corrosion resulting from the reaction of lead with lead dioxide takes place quite slowly under normal circumstances, as a non-porous, the so-called passivating layer is formed on the interface of these substances. The corrosion speed depends on temperature and potential size. It is therefore necessary to prevent the charging at high temperatures (above 40 °C) and overcharging in excess of the technically necessary limit. The passivating layer is interfered also with some impurities from the electrolyte, e.g., anions of organic acids, chlorates, nitrates, or anions that oxidize (e.g., chlorides). The corrosion speed also considerably depends on the crystalline structure of the grid metal. This may be regulated by the accumulator manufacturer by suitable additives or by the grid manufacturing technology (e.g., by the casting regime and cast ageing). The chemicals contained in PowerBatt create, on the grid/active mass interface, the so-called passivating films that significantly reduce the corrosion on this interface. By this, conductivity of the grid/active mass interface is being preserved for long, which results in the preservation of the internal serial resistance of the accumulator at a low value. Increasing Discharging Characteristics

The salts contained in PowerBatt provide for increasing the discharging voltage and thereby also the total quantity of the supplied electric power during discharging. Self-discharge:

It is the reality of each battery design. The battery electrodes submerged in internal processes completely discharged in about 6-9 months. Conventional batteries due to self-discharge, reduce its terminal voltage of about 8-10 mV / day. If the self-discharge is higher than stated, it is mainly due to short-circuits between plates. Common mistakes:

High-rate overcharging After a battery is fully charged, continuation of charging current at a high rate damages positive plates. Violent gassing takes place, bubbles form in the interior of the active material, and the resulting pressure forces bubbles through the porous active material. The active material restrains the bubbles sufficiently so that many particles of plate material are broken out. These particles rise with the bubbles and result in a muddy red or brown color of the electrolyte. Some of this fine sediment settles on negative plates where it short circuits. The sediment is converted to gray sponge lead and results in a growth of moss-like sediment deposited on top edges of the negative plates. This deposit indicates that high-rate overcharging previously occurred. The battery will overheat on sustained heavy charge rates. The temperature of the cells should never intentionally be allowed to exceed 40 °C. Undercharging If the battery gets too little charging, unconverted sulfate remains on the plates too long and hardens. The longer plates stay in less-than-full-charge condition, the harder the sulfate becomes and the more difficult it is to reconvert. When new, the sulfate is easily converted back to soft active materials by a normal charge, but a long overcharge is required to remove it after becoming hard. Sulfate accumulates unnoticed, a little on each charge, if charging is not enough to eliminate all the sulfate. This residue build-up continues until a substantial portion of ampere-hour capacity is lost. The remedy is to increase charging to give a slight overcharge. Prolonged undercharging also leads to large flaking on the interpolate collector bar. Sulfate build-up caused by undercharging is the most common cause of buckling plates and cracked grids. Sulfate takes up more room than the original material and strains the plates out of shape. The pressure of expanding active material can break separators and cause short circuits. If charged at too low a rate, the hardened sulfate is thrown out of plates and settles in white ridges on the cell bottom. At higher rates, the gassing distributes the sediment evenly without ridges. Buckled or cracked plates cannot be repaired by removal of sulfate but may be used as long as they retain satisfactory ampere-hour capacity. Over discharge The plates suffer greatly when over discharged. Voltage per cell should not be allowed to drop below 1.75 volts. Specific gravity should not be allowed to decrease below the limit given by the manufacturer, which is different for various types and sizes of cells. As normal discharge proceeds, active materials are converted to normal lead sulfate, which requires only slightly more space than active materials. Over discharge forms more lead sulfate in the pores of the active material than they are able to hold. This process may expand and bend or buckle plates or crack grids. In some instances, sufficient pressure is created to crack or puncture separators.