Outback Power Systems EnergyCell RE Battery Owners Manual - Manual (Page 9)

EnergyCell Batteries
900-0127-01-00 Rev D 9
System Layout
CAUTION: Fire Hazard
Failure to ventilate the battery compartment can result in the buildup of
hydrogen gas, which is explosive.
 The battery enclosure or room must be well-ventilated. This protects against accidental gas buildup.
All EnergyCell batteries are sealed and do not normally emit noticeable amounts of gas. However, in
the event of accidental leakage, the enclosure must not allow gas to become concentrated.
 The battery enclosure or room must have adequate lighting. This is necessary to read terminal
polarity, identify cable color, and view the physical state of the battery as required.
 The battery should be installed with a minimum 36” (91.4 cm) clearance in front. This allows access for
testing, maintenance, and any other reasons.
 If multiple batteries are installed, they should have a minimum of ½” (12.7 mm) clearance on
either side.
Battery Configurations
Figure 6 Series String Configurations
Figure 7 Parallel String Configuration
Series String (24 Vdc) Series String (48 Vdc)
Load + Load – Load + Load –
Batteries are placed in series (negative to positive) for additive voltages. Batteries in series are known as a
“string”. A string of two EnergyCell batteries has a nominal voltage of 24 Vdc and can be used for 24-volt
loads. A string of four has a nominal voltage of 48 Vdc. Other voltages are possible. However, batteries in
series do not have additive amp-hours. A single string of any voltage (as shown above) has the same
amp-hours as a single battery.
When replacing batteries, a new battery should not be placed in series with old batteries. This will cause
severe stress and shorten the life of all batteries. All batteries in a string should be replaced at the same time.
Batteries are placed in parallel (positive to positive,
negative to negative) for additive amp-hour capacity.
Three batteries in parallel have three times the
amp-hours of a single battery. However, batteries in
parallel do not have additive voltages. A single set of
batteries in parallel (as shown in this figure) have the
same voltage as a single battery.
NOTE: Use caution when designing or building systems
with more than three batteries or strings in parallel.
The extra conductors and connections used in larger
paralleled systems can lead to unexpected resistances
and imbalances between batteries. Without proper
precautions, these factors will reduce the system
efficiency and shorten the life of all batteries. Parallel Batteries
Load Bus + Load Bus –