Civil Engineering Reference
In-Depth Information
FIGURE 10-20
Battery management microprocessor for photovoltaic power system. (Source: Morningstar Cor-
poration, Newtown, Pennsylvania. With permission.)
10.9.2
Safety
The battery operation requires certain safety considerations. The most impor-
tant is not to overcharge the battery. Any overcharge above the trickle charge
rate is converted into heat, which can explode the battery if allowed to build
up beyond limit. This is particularly critical when the battery is charged
directly from a photovoltaic module without a charge regulator. In such
cases, the array is sized below a certain safe limit. As a rule of thumb, the
photovoltaic array rating is kept below the continuous overcharge current
that can be tolerated by the battery. This is typically below C/15 amperes
for the lead-acid batteries.
