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Installation, commissioning and operating instructions for valve-regulated stationary lead-acid batteries
7140203153 V1.4 (09.2018)
Installation, commissioning and operating instructions for valve-regulated stationary lead-acid batteries
7140203153 V1.4 (09.2018)
6 Battery operation
DIN VDE 0510 Part 1 and IEC 62485-2 apply for the operation of stationary battery systems.
Each battery is subject to a natural electro-chemical aging process, which causes the reduction
of the metallic lead within the battery (corrosion). The progress of the aging process and also the
service life of the battery depend significantly on the operating temperature.
Attention!
The recommended operating temperature for lead-acid batteries is between 10 °C and 30 °C.
Technical data is valid for the nominal temperature of 20 °C. The ideal operating temperature
range is 20 °C ±5 K. Higher temperatures shorten the service life of the battery. Lower temperatu-
res decrease battery capacity. Exceeding the limit temperature of 55 °C is not permissible. Avoid
operating at temperatures in excess of 45 °C for long periods of time.
The natural aging process and thus the service life expectation play an important role especially in
high current applications. A high current application is an application with currents and discharge
rates ≤ C
0,5
. Discharging with high currents results in disproportionately more heat, which may
lead to a thermal overload of the corroded metallic conductor. From a certain level of the aging
progress the reduced cross sections are not able to conduct the designed maximum permitted
current for the defined period. In an extreme case this can result in an unexpected battery failure.
Attention!
The capacity test helps to check the efficiency and safety of the batteries and can thus avoid an
unexpected battery failure. Please note, that during the capacity test the load current must corre-
spond to the maximum permitted current for which the battery is designed. Regular review of the
batteries in compliance with specifications defined in Chap. 9 (Testing the battery system) gene-
rally eliminates the risk of an unexpected battery failure. We recommend performing the capacity
test in accordance with Chap. 9 periodically, but at least once a year. In light of past experience
during the first 3 years of the operating life of the batteries the capacity test can be omitted.
6.1 Discharging
Attention!
Never allow the final discharge voltage of the battery to drop below the voltage corresponding to
the discharge current.
Unless the manufacturer has specified otherwise, no more than the nominal capacity is to be
discharged. Immediately after discharge (including partial discharge), charge the battery comple-
tely.
6.2 Charging - general
Depending on how the batteries are used, charging is to be carried out in the operating modes described in
Chap. 6.2.1
to
Chap. 6.2.4
.
Apply the charging procedure with limit values in accordance with DIN 41773 (lU characteristic
curve).
Attention!
Superimposed alternating currents
Depending on the charger type and charging characteristic curve, alternating currents flow through
the battery during charging and are superimposed onto the charging direct current. These superim-
posed alternating currents and the reaction of the loads lead to additional heating of the battery
or batteries and create a cyclical strain on the electrodes. This might result in premature aging
of the battery.
Attention!
After recharging and continuous charging (float charging) in standby parallel operation or floating
operation, the effective value of the superimposed alternating current is not permitted to exceed
5 A per 100 Ah nominal capacity.
In order to achieve the optimum service life for sealed lead-acid batteries on float charge, a
maximum effective value of the alternating current of 1 A per 100 Ah nominal capacity is recom-
mended.
Attention!
Temperature-related adjustment of the charge voltage
Within the operating temperature range of 15 °C to 25 °C, temperature-related adjustment of the
charge voltage is not necessary.
If the operating temperature is constantly outside this temperature range, the charge voltage
must be adjusted.
The temperature correction factor is approx. -0.003 V/cell per K.
Temperature [°C]
-10
0
10
20
30
40
Charge voltage [V/cell]
2.34
2.31
2.28
2.25
2.22
2.19
Tab. 6–1: Corrected charge voltage in relation to charge temperature for battery types with 2.25 V/cell float charge
at T
nom
Fig. 6–1: Temperature related float charge voltage adjustment
Attention!
Maximum charge currents
Up to 2.4 V/cell the battery is able to absorb the maximum current the battery charger provides.
Using the IU-characteristic according to the DIN 41773 a charging current of 5A to 20A per 100Ah
rated capacity (C
10
) is recommended.
Temperature [°C]
Charge Voltage [V/Cell]
-10 -5 0 5 10 15 20 25 30 35 40
2,35
2,34
2,33
2,32
2,31
2,30
2,29
2,28
2,27
2,26
2,25
2,24
2,23
2,22
2,21
2,20
2,19
2,18
2,17
2,16
2,15
