Lead acid batteries state of charge,automotive battery maintenance and service,connecting car battery sparks - Plans Download

27.07.2015
The lead acid battery uses lead as the anode and lead dioxide as the cathode, with an acid electrolyte. During the charging process, the reactions at each electrode are reversed; the anode becomes the cathode and the cathode becomes the anode.
During charging, given the high voltage, water is dissociated at the two electrodes, and gaseous hydrogen and oxygen products are readily formed leading to the loss of the electrolyte and a potentially explosive situation. Under certain circumstances the lead sulphate products at both the electrodes achieve an irreversible state, making the recharging process very difficult. Pure lead is too soft to use as a grid material so in general the lead is hardened by the addition of 4 – 6% antimony. The function of the grid is to hold the active material and to conduct electricity between the active material and the battery terminals. Ball milling: Pieces of lead are put into a rotary mechanical mill, forming fine lead flakes, which are then oxidised in air and removed. Red lead (Pb3O4) can also be added to the PbO formed by these methods, as it is more conductive. The oxide is mixed with water, sulphuric acid and a mixer, and then mixed to form a paste.
The simplest cell would consist of one cathode plate, one anode plate and a separator between them. Most lead-acid batteries are constructed with the positive electrode (the anode) made from a lead-antimony alloy with lead (IV) oxide pressed into it, although batteries designed for maximum life use a lead-calcium alloy. When the battery is discharged water is produced, diluting the acid and reducing its specific gravity.
The chemical reactions that occur during charging and discharging are summarised in figures 1 and 2.
If lead-acid batteries are over discharged or left standing in the discharged state for prolonged periods hardened lead sulphate coats the electrodes and will not be removed during recharging. Starting Batteries – Used to start and run engines they can deliver a very large current so a very short time, discharging by about 2-5%.
Marine Batteries – Usually a hybrid battery that falls between deep cycle and starting batteries although some are true deep cycle batteries.
Absorbed Glass Mat (AGM) Batteries – The electrolyte is held between the plates absorbed in a fine boron-silicate mat. WelcomeThis site is aimed at providing technical resources and information to assist Appropriate Technology (AT) specialists working in the following areas: drinking water supply, sanitation, electrical supply, construction, fuel-efficient cooking stoves and environmental education.
Our MissionITACA understands AT as technologies that are easy to construct and maintain, low cost, using local resources as far as possible, simple to replicate and adapt to different contexts, and both environmentally and economically sustainable in the long-term. BienvenidoEste sitio esta dirigido a proporcionar los recursos tecnicos e informacion para ayudar a la Tecnologia Apropiada (AT) especialistas que trabajan en las areas siguientes: abastecimiento de agua potable, saneamiento, suministro electrico, construccion, bajo consumo de combustible de cocinas y educacion ambiental.
Please enable Javascript support in your browser and refresh this page before you continue. The voltage of a lead acid battery when at rest (not supplying current or being charged) will vary according to how fully charged the battery is. The graph shown to the right represents a typical 24 volt lead acid battery which has not been charged or had current drawn from it for a couple of hours.


With further drawing of current, the rate of voltage drop slows down and will reach around 24.0 volts when the bettery is at half capacity. As the battery approaches the fully discharged state, the voltage starts to fall more quickly again. It is important for a battery to never be fully discharged, so your inverter will normally disconnect the supply when the voltage is around 22 volts.
An interesting point to note here is that when an inverter or other power load is drawing a high current from the battery, the voltage will drop. The larger the battery, the smaller this voltage drop will be, and the greater the % of the charge will be useable when drawing high currents. If a voltage is applied to the battery which is greater than the battery's voltage, a current will flow through the battery in the reverse direction to when it is supplying current, and the battery will charge.
The rate of charge or current that will flow will depend on the difference between the battery voltage and the voltage that is applied to it (from solar panels etc).
While it is beneficial to a battery's performance and life to be fully charged on regular occasions, however once a battery has been charged to it's full capacity, it is important not to continue charging as this will damage the battery. The Lead Acid battery is not 100% efficient at storing electricity - you will never get out as much as you put in when charging. The efficiency will depend on a number of factors including the rate of charging or discharging. However it has been found that if a battery is only partially charged, efficency may be reduced with each charge.
The most common is the SLI battery used for motor vehicles for engine Starting, vehicle Lighting and engine Ignition, however it has many other applications (such as communications devices, emergency lighting systems and power tools) due to its cheapness and good performance. Strips of lead foil with coarse cloth in between were rolled into a spiral and immersed in a 10% solution of sulphuric acid.
These act as grain refiners, decreasing the grain size of the lead and thereby increasing its hardness and strength.
This is often used for telephone applications, and for no maintenance automotive batteries, since a more stable battery is required. Each droplet reacts with the air to form an oxide layer, giving 70 – 85% lead oxide.
The negative electrode (the cathode) is made from pure lead and both electrodes are immersed in sulphuric acid. On charging sulphuric acid is produced and the specific gravity of the electrolyte increases.
Lead (IV) oxide is formed at the anode, pure lead is formed at the cathode and sulphuric acid is liberated into the electrolyte causing the specific gravity to increase. Lead sulphate is formed at both electrodes and sulphuric acid is removed from the electrolyte causing the specific gravity to reduce.
If deep cycled these batteries quickly degenerate and will fail after 30-150 cycles but should last for a very long time when used correctly.
Standard types have removable caps so that the electrolyte can be diluted and the specific gravity measured, such batteries are supplied dry and you add distilled water. The electrolyte can not be diluted so that over charging must be avoided and these batteries may only last for 2 or 3 years in hot climates although with good care they can last for 5 years.


Like gelled electrolyte batteries they will not leak acid but they can withstand more careless treatment and are less sensitive to over charging since they are designed to retain vented gases.
We see AT as a tool to address the inequalities and injustices faced by millions of communities around the world who lack access to the basic resources required for a dignified life.
As current is drawn off and the level of charge is reduced, the voltage will fall quite quickly at first (again it would be necessary to stop drawing current for a couple of hours to be able to measure the true voltage of the battery).
This may mean that the battery needs to be somewhere over 50% charged to avoid the inverter cutting out due to low voltage.
Solar panels intended for a 24 volt system are likely to be capable of producing over 30 volts. With the battery at half charge or less, the charge efficiency may be over 90%, dropping to nearer 60% when the battery is above 80% charged. If this situation persists (the batteries never reaching full charge), the life of the battery may be reduced. The cell was further developed by initially coating the lead with oxides, then by forming plates of lead oxide by coating an oxide paste onto grids.
The molds are closed and filled with sufficient molten lead to fill the mold, leaving some excess to form a sprue, which is then removed by cutting or stamping. The separators are usually cellulose, PVC, rubber, microporous polyethylene or non-woven polypropylene. These batteries are designed to discharge by as much as 80% of their capacity over thousands of charging and discharging cycles.
Standard flooded batteries are cheap and if they are kept topped up they are not overly sensitive to high charging voltages. AGM batteries can also stand for 30 days in a totally discharged state and still be recharged successfully. The specific gravity also depends on the battery temperature and the above values or for a battery at 15°C. True deep cycle batteries have solid lead plates however many batteries that do not have solid plates are called semi-deep cycle. Sealed batteries are supplied pre-flooded and have fixed valves to allow gases to vent during use however, they will still leak if inverted and the electrolyte can not be replenished so that over charging will cause damage.
The major drawback to these batteries is that they cost between 2 or 3 times as much as flooded batteries.
The tabs that are fixed to the plates are cast, then punched on between the layers and welded together. The plates are suspended inside the case, which is filled with electrolyte in order to activate it.



Charge car battery via cigar lighter naturally
Laptop battery toshiba


Comments Lead acid batteries state of charge

  1. Brad_Pitt
    Both feature an automated refresh cycle which executive or luxury.
  2. Lezgi_tut_ya
    Out batteries every few years.