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Sequence of performance of the tests
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5.1
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5.1.1 The tests for:
-5h capacity (see 5.2)
-charge retention (see 5.3)
-1h high-rate discharge performance (see 5.4)
May be carried out either on a new complete battery or on a representative part there of in the order listed here.
For acceptance or commissioning a 5h capacity test or as agreed upon between battery supplier and battery user shall be selected.
The charge retention test and the high-rate discharge ability test are optional.
5.1.2 The test for endurance in cycles (see 5.5) is a destructive test and shall be executed on a minimum of three cells of the same type.
Suitable packing should be provided for the test samples in order to maintain the same dimension as when installed in batteries.
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Capacity test
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5.2
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5.2.1 To facilitate the temperature readings, one pilot cell is selected per group of six cells, the average of the pilot cells being considered as representative of the average temperature of the battery.
The temperature of each of pilot cell shall be read immediately prior to the discharge. The individual readings shall be between 15 and 40℃. The average initial cell temperature t0 is calculated as the arithmetic mean of the individual values.
5.2.2 The battery shall be completely charged in accordance with 4.3.
5.2.3 Within 1h to 24h after the end of charging ,the battery shall be subjected to a discharge at the current IN (see 3.1.2)
This current shall be maintained constant within ±1% throughout the whole discharge time.
5.2.4 The voltage across the terminals of the battery (excluding battery output cables),shall be either recorded automatically against time, or noted at suitable time intervals using a voltmeter(see 4.1.1.2)
5.2.5The discharge is discontinued when the average voltage has reached the value of 1.7V per cell. The discharge time shall be noted.
5.2.6The uncorrected capacity C (Ah) at the initial temperature t0 is calculated as the product of the discharge current (in amperes) and the discharge time(in hours).
5.2.7 If the initial temperature t0 (see 5.2.1) is different from the reference temperature (30℃).the capacity C. in accordance with 5.2.6,shal be corrected to the actual capacity Ca by the equation:
Ca= (Ah)
Where
T0 is the initial temperature;
tr is the reference temperature(30℃)
=0.006(℃)-1 for the 5h capacity.
5.2.8 A new battery, submitted to the rated capacity test, when subjected to repeated CN discharge/charge cycles according to 5.2.2 to 5.2.6 shall supply at least
Ca=0.85 CN at the first cycle;
Ca=1.00 CN at or before the tenth cycle.
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Charge retention test
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5.3
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5.3.1 after having undergone a capacity test in accordance with 5.2, and having obtained a capacity Ca ＞CN, the battery is recharged in accordance with 4.3. Its surfaces shall be cleaned and dried in order to remove any traces of conductive material or electrolyte.
5.3.2the battery shall be stored on open circuit(i.e. without a connected electric load) at an average cell temperature of 20℃±2℃ for a period of 28days(672h).
During that time, the maximum cell temperature shall not exceed +25℃ and the minimum temperature shall be not less than +15℃.
5.3.3 at the end of the open circuit storage, in accordance with 5.3.2,the temperature of the cells is adjusted to the range indicated in 5.2.1.then the residual capacity Ct shall be determined by a discharge at the standard current IN(see 3.1.2) and thereafter in accordance with 5.2.4 to 5.2.7
5.3.4 The residual capacity. Cr shall be not less than 0.85Ca.
5.3.5 After the test, the battery shall be fully recharged in accordance with 4.3.
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High-rate discharge performance test
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5.4
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5.4.1 The test to verify the high-rate performance value(It) shall be carried out on a new battery having obtained a capacity Ca.≥ CN in accordance with 5.2.
5.4.2 The initial battery temperature (t0) and the ambient temperature shall be in accordance with 5.2.1.
5.4.3 Within 1h to 24h after the end of charging. The battery shall be subjected to a discharge at the current I1 specified by the manufacturer(see 3.3)
The average discharge current shall correspond to I1±1%. Current deviation shall not exceed ±5% I1of at any time.
5.4.4 the voltage across the terminals of the battery(excluding battery output cables) shall be either recorded automatically ,according to the following equation:
Th=1(h)[1+l2(t0-30(℃))]
Where l2=0.01(℃)-1 for the 1h capacity.
5.4.6 the cells/ monoblocs or batteries shall be discharged for a period of Th hours when the final average voltage per cell shall be not less than 1.60V.
Should however the average voltage of 1.60V per cell be reached prior to discharge Th. the current may be interrupted. In this case, the cells or batteries on discharge have failed this test.
5.4.7 After the test, the battery shall be fully recharged in accordance with 4.3.
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Cyclic endurance test
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5.5
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5.5.1 the test shall be carried out on cell samples as specified in 5.1
5.5.2 After undergoing the actual capacity test of 5.2 and having shown a capacity Ca at least equal to the nominal capacity CN, the cells shall be recharged as specified in 4.3.
5.5.3 The cells/monoblocs shall the be connected to a device where they shall undergo a continuous series of cycles throughout the test, each cycle comprising the following:
5.5.3.1Vented cells
-A discharge for 3h at a current of I(A) = CN (Ah)/4(h).
-A recharge for 9h immediately following the discharge, supplying the battery with a charged capacity as defined in Table 1 below, the current at the end of charge being not greater than I(A) = CN (Ah)/16.66(h).
Table 1- cell recharge factors
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Recharge capacity
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Charge factor
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Cell type
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0.864C
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1.15
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A,B,C,D(IEC60254-2, Table1)
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a,b,c,d(IEC60254-2, Amendment 1, Table 2)
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0.937C
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1.25
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E,F,G(IEC60254-2, Table1)
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e,f,g(IEC60254-2, Amendment 1, Table 2)
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0.787C
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1.05(typical)
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Cells with electrolyte agitation
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NOTE 1 Cells having electrolyte agitation require a lower charge factor as indicated above. Cells having increased electrolyte density may require a higher then normal charge factor. In these cases, and where other special features are incorporated, the manufacturer’s instructions should be followed.
NOTE 2 Where monobloc batteries or cells do not conform to the dimensions defined in IEC 60254-2, Tables 1 or 2, a recharge capacity/charge factor should be applied that is appropriate to the cell height when compared with cells in these tables.
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5.5.3.2 Valve regulated cells
-A discharge for 3.5h at a current of I(A) = 0.2CN (A).
-Unless otherwise recommended by the manufacturer, a recharge for a maximum of 14h immediately following the discharge, at a constant voltage not exceeding 2.4V per cell, with a current limit during the last 2h not greater than I(A) = CN (Ah)/66.66(h).
NOTE During the initial part of the constant voltage charge a current limitation may be accepted or recommended for service life reasons.
During the last 2h of charge, the voltage may be allowed to rise above 2.45V per cell.
5.5.3.3 Throughout the whole of either test 5.5.3.1 or 5.5.3.2, the temperature of the cells shall be maintained between 33℃ and 43 ℃.
5.5.4 After each series of 50 cycles ±5 cycles, the cells/monoblocs shall undergo a capacity test as specified in 5.2.
The test shall be considered as terminated when the corrected capacity Ca resulting from this test is less than 0.8 CN during two successive series of 50 cycles ±5 cycles each.
5.5.5 The endurance in cycles is the number of cycles completed up to the end of the first of the two final series. This number shall be at least equal to the number stated by the manufacture.
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