SMA S Technical Description page 171

SMA Solar Technology AG Glossary
Battery
A battery is an electrochemical storage device which can release previously stored chemical energy
as electrical energy. A distinction is made between non-rechargeable primary elements (often used in
(e.g.) consumer markets) and rechargeable secondary elements (accumulators). In stand-alone grid
systems, the batteries used as rechargeable secondary elements are almost exclusively lead acid
batteries and, very rarely, nickel/cadmium batteries.
Battery Bank
See Battery System.
Battery Charging Mode
A battery inverter operating mode, in which the inverter takes energy from the AC grid to recharge
the battery in a controlled fashion. In this operating mode, the battery inverter is primarily responsible
for correctly charging the battery, and acts as an independent battery charger.
Battery Inverter
See Battery Power Converter.
Battery Management
The battery management is responsible for optimal battery charging and reliable protection against
deep discharge. This is the only way of ensuring that the battery service life reflects the manufacturer's
specifications.
Battery Power Converter
A bidirectional power converter which can regulate voltage and frequency in a stand-alone grid and
is also responsible for correct battery charging.
Battery System
Series connection and possibly also parallel connection of several identical batteries. Battery banks
of 12 V, 24 V, 48 V and 60 V are typical.
Boost Charge
Boost charge: allows the batteries to be charged to a level of approx. 85 – 90 % in the shortest time
and the most efficient manner.
Bulk Phase
I phase: The charging phase in which charging can be done using the maximum allowable charging
current.
Capacity
Describes the storage capability of a cell or battery, specified in Ah (ampere hours). The capacity of
a battery is heavily dependent on the charging cycle, the amount of current drawn and the
temperature.
Central Inverters
An inverter concept in which all PV modules are connected to each other (in series and/or parallel)
and which uses a single inverter for feeding energy into the external grid. The lower cost of the inverter
is usually offset by the much higher installation outlay required and possible yield losses due to
variations in shadowing on individual solar modules.
Technical Description SBU2200-TEN083320 171