Information of Starting Battery in Diesel Generator Set

To understand the start-up battery of diesel generator, the first thing is to understand the principles of the battery. Contents below explain the battery knowledge.

Principle of Battery: battery is the combination of many battery individuals, including many metal sheets and electrolytes. Electrical energy is generated by biochemical reaction in the battery, and the reverse reaction is reversible, which means that the battery can be recharged and discharged.

Electrolyte: These conductive liquids, called electrolytes, are diluted sulphuric acid solutions in an aluminate cell. It causes the metal sheet to react and become a conductive medium.

Proportion: Specific gravity is a unit of measurement used to determine the concentration of sulfuric acid in the electrolyte, which compares the weight of the electrolyte to the weight of water. A charged battery at 25 degrees Celsius should have a specific gravity of 1.270, and the thinner the sulfuric acid solution, the lower the specific gravity. The chemical reaction reduces the specific gravity of sulfurous acid in the electrolyte when the battery discharges. Therefore, this measurement can be seen as a guide to battery charging.

Densimeter: The hydrometer can be used to measure the specific gravity directly. The device is a spherical suction tube which draws the electrolyte from the battery hub and draws the glass buoy in the hydrometer column to scale out the specific gravity. Do not immediately measure the specific gravity of the battery after adding water to it. Charge the battery so that the water is mixed with the precipitated sulfuric acid so that the measured specific gravity is reliable. Also, the specific gravity of the battery is measured after a long period of time at the disposal of the starting machine, and its value is higher than its true value. Water formed by the motor during rapid discharge will have no time to mix with the electrolyte above the motor.

High or low temperature: In tropical climates (often above 32 degrees), a full battery with a specific gravity of 1240 should be used, a medium strength electrolyte that prolongs the battery's life. If the cell is used in a low temperature environment, there will not be enough power to power it up because of lower sulfuric acid concentrations, but not in tropical climates. Batteries used in extremely cold climates need stronger electrolytes, and in some cases when the specific gravity of 1.290-1.300 increases, the ability to start cold will also increase.

Temperature Correction: The scale of the hydrometer is corrected at 25 degrees, the specific gravity of the electrolyte is corrected with the temperature higher than the above reference temperature, the specific gravity is corrected accordingly, the reading of each increase of 5.5 degrees should be increased by 0.004 degrees and the number of degrees shall be reduced by 0.004 degrees when the temperature is reduced by 5.5 degrees compared to the normal temperature.

The storage battery of diesel generator set is the power supply equipment to start the motor. When the diesel engine starts up, it is required that the battery can supply low voltage and high current to the starting motor in a short time (200 ~ 600A). The output voltage of the generator is insufficient or stopped when the diesel engine stops at low speed and the battery supplies the required current to the electrical equipment of the diesel engine. So how do batteries usually need to be maintained? Below are some tips for battery maintenance for diesel generator set. 

1. Battery in use, to install firmly, wiring clip and battery cable contact is good. Coat the connecting column with butter to avoid oxidation.

2. The starting time of diesel engine is not allowed more than 10 seconds, and the interval of the second start should be more than 2 minutes. Avoid the battery continuous discharge time too long because of thermal deformation, resulting in short circuit or material fall off, battery capacity reduced.

3. Check the exhaust hole on the seal cover to keep it open at any time to prevent battery burst caused by blockage.

4. Keep the storage battery surface clean and clean with distilled water or purified water when there is acid.

5. Batteries should be used for a long time with distilled water (do not add electrolyte or sulfuric acid) in order to prevent the plate from oxidation and affect the storage battery capacity.

6. When the diesel engine does not work for a long time, the battery should be charged by starting the diesel engine regularly or charging the battery with a special charger.

7. Regularly check the height of the electrolyte inside the battery. When the stick is inserted into a single cell to contact with the perforated plate, the height of the electrolyte should be 10 ~ 15m higher than that of the electrode plate when the stick is taken out to observe the electrolyte height.

8. Check the density of the electrolyte. When the densitometer rubber tube is inserted into the battery and the electrolyte is inhaled until the densitometer is just floating and the upper end is not held up, the scale of the densitometer aligned with the liquid level is the density of the electrolyte.