HYBRID INVERTER | Installer Manual
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The batteries recommended for use with the Sunsynk systems are AGM Lead Acid or Lithium Battery Banks.
(‘AGM’ means Absorbed Glass Matt construction that allows the electrolyte to be suspended new the plate’s
active material. In theory, this enhances both the discharge and recharging efficiency. AGM batteries are very
heavy as a result).
State of Charge
Bulk:
The bulk charge is the first stage of a battery’s charging process, where the charger identifies the
battery and its needs and then applies a high voltage to do the bulk of the charging. It involves about 80% of
the recharge. The properly sized charger will give the battery as much current as it will accept up to charger
capacity (25% of battery capacity in Amp hours).
Absorption:
To fully charge a battery, a period of charging at a relatively high voltage is needed. This period
of the charging process is called absorption. This occurs when the charging of a battery has reached 80%
of its capacity. The remaining charge equals 20% approximately. It makes the charger hold the voltage at
the charger’s absorption voltage (between 14.1 VDC and 14.8 VDC, depending on charger set points) and
decreases the current until the battery is fully charged.
Float:
The charging voltage is reduced to between 13.0 VDC and 13.8 VDC and held constant, while the
current is reduced to less than 1% of battery capacity. This mode can be used to maintain a fully charged
battery indefinitely.
Equalisation:
This is essentially a controlled overcharge that occurs at the end of the Bulk mode and the ab
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sorption phase and is called the ‘equalisation voltage’. However, technically, this phase has another function.
Higher capacity wet (flooded) batteries sometimes benefit from this procedure, particularly the physically tall
batteries. The electrolyte in a wet battery can stratify over time if not cycled occasionally. In equalisation, the
voltage is brought up above the typical peak charging voltage well into the gassing stage and maintained for
a fixed (but limited) period. This stirs up the chemistry in the entire battery, ‘equalising’ the strength of the
electrolyte and knocking off any loose sulphating that may be on the battery plates.
5.13. Setting Up a Lithium Battery
To set up a lithium-ion battery, click on the BATTERY icon and visit the ‘Batt Type’ column.
What this page displays:
This information will only display if the ‘Lithium’ option is selected under ‘Batt Type’.
The type of communion protocol.
Approved batteries.
