All the tests covered in this standard may not be applicable to all types of Batteries. Provisions in the individual specifications shall be applicable.
The Specification does not cover the requirements of batteries for Applications such as Aircraft, Marine and Minors cap lamp.
There are Basically 3 classes of tests:
1. TYPE TEST:
These tests are carried out to ensure that the batteries offered are in conformity with the requirement in terms of General Quality and Design of a required type of Battery
2. ACCEPTANCE TEST:
These tests are carried out on samples selected from a LOT for verifying the acceptance of the LOT.
[What comprises a LOT? All cells and Batteries of SAME TYPE, DESIGN & RATINGS manufactured in the SAME FACTORY during the SAME PERIOD using SAME PROCESS & MATERIALS.]
3. ROUTINE TESTS:
These are the test carried out on each and every battery.
We have not considered the general and physical requirements like materials, construction, dimensions, marking & packing and have elaborated only Electrical test.
(An instrument to measure battery terminal voltage) – This should be of 0.5% accuracy class or better as per IS 1248. The internal resistance of the voltmeter should be at least 1000 Ohms per volt. This could be analogue or digital type.
(An instrument to measure battery charge/discharge current) – This should be of 1.0% accuracy class or better (analogue or digital)
(An instrument to measure temperature) – Thermometers of appropriate scale with least count of 1 deg C and accuracy of 0.5 deg c are required.
(An instrument used to measure specific gravity of electrolyte) – The graduations on the Hydrometer should be 0.005 units of specific gravity and accuracy of 0.005 units.
5. Constant current discharge unit
This is required to discharge battery at desired current which will be maintained constant at set value within +- 1% or better. Current range will depend on the capacity of the battery to be tested.
This unit is useful in conducting capacity test, loss of capacity test, storage test, as well as high rate discharge at normal as well as low temperatures.
6. Constant current charger and discharger fitted with ampere hour meter or timer
This is necessary for carrying our ampere hour and watt hour efficiency test. This is also useful for conducting charge/discharge cyclic test (endurance and life cycle) as well as resistance to overcharge test.
7. Constant Potential charger fitted with timer
This is required for conducting Charge Acceptance Test & Water Loss Test.
8. Data Acquisition system (Data loggers)
These are essential for capturing and storing test data like battery voltage, charge/discharge current, bath temperature, electrolyte temperature, ampere hours etc at preset time interval.
Battery capacity is expressed in ampere hours (corrected at 27 deg C) This rating would be obtained when the cell/battery is discharged at a specific rate till the battery terminal voltage on load reaches specified voltage at specified specific gravity of electrolyte at the beginning of the discharge. The multiplication of discharge current in amps and total discharge time in hours gives the ampere hour capacity of the battery.
Capacities at various rates of discharge like C1, C3, C5, C10 etc. are different. These are specified in individual specifications.
C 27 = Ct /1+0.01 (T-27)
Requirement: The capacity in ampere hours thus obtained should be within 100-120% of rated ca