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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)
Sum of factors:
Parameter
Lead-acid batteries
sealed cells
f
g
: Gas emissions factor
0.2
f
s
: Safety factor for gas emissions
(includes 10% faulty cells and aging)
5
U
float
: Float charge voltage, V/cell
2.27
I
float
: Typical float charge current, mA per Ah
1
I
gas
: Current (float charge), mA per AH
(used only for calculating the air volume flow for float charge)
1
U
boost
: Boos charge voltage, V/cell
2.40
I
boost
: Typical boost charge current, mA per Ah
8
I
gas
: Current (boost charge), mA per Ah (used only for calculating the
air volume flow for boost charge)
8
Tab. 5–2: Recommended current values (Extract from the IEC 62485-2)
If designing the ventilation in battery rooms, depending on the structural conditions, either „natural ventilation“
or „technical ventilation“ can be used.
Observe the following points:
Natural ventilation:
– intake and exhaust openings required
– minimum cross-section (free opening in wall) (A in cm
2
, Q in m
3
/h) (given that: v
air
= 0.1 m/s)
– increased ventilation through chimney effect (air routing)
– exhaust released outside (not into air-conditioning systems or surrounding rooms).
Technical ventilation:
– increased ventilation using fan (generally extractor fans)
– air flow rate according to air volume flow Q
– air drawn in must be clean
– if large amounts of gas are released during charging, continued ventilation is required for 1 h after charging
is complete
– for multiple batteries in one room: required air flow = ∑Q
– avoid a ventilation short circuit by ensuring that there is sufficient distance between the intake and exhaust
opening.
In case of a technical (forced) ventilation the charger shall be interlocked with the ventilation system or an alarm
shall be actuated to secure the required air flow for the selected charging mode.
with
5.2 Filling the cells
Sealed lead-acid batteries are always filled before delivery. Sealed stationary lead-acid battery
cells must not be refilled with water during the entire battery service life. Overpressure valves are
used as sealing plugs. These plugs cannot be opened without damaging.
5.2.1 Check
Make sure that the installation and ventilation requirements according to IEC 62485-2 are met.
Should commission charging be carried out using higher amperage than you established for the type of ventilation
equipment, then you must increase the ventilation in the battery room (e.g. using additional portable fans) accor-
ding to the amperage applied.
Increased ventilation has to be applied during commissioning and for one hour afterwards. The same applies for
occasional special battery charging processes.
5.2.1.1 Ventilation - preventing explosion
It is impossible to stop gases from being generated while charging batteries; therefore, the hydrogen concen-
tration in the air must be reduced with sufficient ventilation. Do not use sparking equipment near batteries.
The following could act as sources of ignition for gas explosions:
– open flames
– flying sparks
– electrical, sparking equipment
– mechanical, sparking equipment
– electrostatic charge.
Observe the following measures to prevent gas explosions:
– sufficient natural or technical ventilation
– no heating using open flames or glowing objects (T > 300°C)
– separate battery compartments with individual ventilation
– anti-static clothing, shoes and gloves (according to applicable DIN and EN regulations)
– surface conductivity resistance: <10
8
Ω and insulating resistance ≥ 10
5
Ω
– hand-held lights with power cable without switch (protection class II)
– hand-held lights with battery (protection category IP54)
– warning and regulatory signs.
The ventilation requirements for battery rooms, cabinets or compartments are based on the required reduction
of the concentration of hydrogen generated during charging and safety factors which include battery aging and
the potential for fault (“worst case”).
5.2.1.2 Ventilation - calculation for ventilation requirements of battery rooms
Air volume flow Q:
v = dillution factor = 96% air/4% H
2
= 24
q = quantity of hydrogen generated = 0.42 10
–3
m
3
/Ah
s = safety facotr = 5
n = number of cells
I
Gas
= current per 100 Ah
C = nominal capacity of the battery
