Lead acid batteries, Physics

 

Lead acid batteries:

Lead acid cells have a nominal voltage of 2 Volts, therefore a typical 24V aircraft battery would consist of 12 cells connected in series. The active material in the positive plates is Lead Peroxide (Pb02) the negative plates, Spongy Lead (Pb). The electrolyte is dilute sulphuric acid (2H2SO4).

Construction:

1275_Lead acid cells.png

There are two forms of Lead Acid battery construction, conventional and solid block, often referred to as a Varley type battery.

In the conventional battery the plates consist of lead grids into which the active materials are pressed. The positive and negative plates are then interleaved and connected to a lug that forms both a mechanical support and the terminal.

Cells are generally constructed with an additional negative plate, making both outside plates negative. This ensures that chemical action takes place on both sides of each positive plate. When chemical action only takes place on one side of a positive plate it tends to buckle.  

The plate arrangement is then inserted into a composite material container which is fitted with a lid. The inside of the container is ribbed to provide additional support for the plates, which are raised clear of the bottom of the container to prevent shorting by any sediment that forms.

To provide further support for the plates and to ensure they cannot touch, separators are fitted, these were originally cedar wood but modern batteries use micro-porous plastic materials.

Each cell is fitted with a special non spill valve that allows gasses to escape, but prevents the spillage of electrolyte, this valve can be removed for checking and adjusting the electrolyte level.

The electrolyte used is sulphuric acid diluted with pure distilled water, the specific gravity of the electrolyte used is determined by the manufacturer, however, it is generally lower than 1300.

 

 

 

Posted Date: 9/13/2012 1:59:02 AM | Location : United States







Related Discussions:- Lead acid batteries, Assignment Help, Ask Question on Lead acid batteries, Get Answer, Expert's Help, Lead acid batteries Discussions

Write discussion on Lead acid batteries
Your posts are moderated
Related Questions
A 10 kg block slides down a smooth inclined surface as shown in Figure 1. Determine the terminal velocity of the block if the 0.1 mm gap between the block and the surface contains

What are the steps to the scientific notation? To write in scientific notation, you should first move the decimal point of the number to where the number is among 1 and 9. For

projectile down an inclined plane

Eye Chamber: The ball is separated into two chamber, the aqueous chamber and the vitreous chamber. Working: Parallel rays from an object converged by the eye lens and b


What instrument is used to measure volume? Liquid volume is calculated with beakers, measuring cups, spoons, graduated cylinders, and the like. For regular objects, solid volum

Nuclear Decays Uses a proper Monte Carlo engine to simulate real decays.The decay of 500 atoms of the fictional element Balonium.

A substance has constant heat capacity C P = 3.5R and its equation of state is given by: P (V-cRT) = RT where c = 5 * 10 -7 m 3 /J. This substance is isentropically compre

The species, which accepts the electrons, are known as Electrophiles (or) Electrophilic reagents. When the atom (or) group of atoms there in the organic compound is replaced by

What are mass defect and binding energy? How is mass defect related to binding energy? Describe the term ‘decay constant' for a radioactive substance. Reduce the relation betwee