NOT need to fully charge the batteries each cycle in order to maintain the capacity
however see the section below on periodic fast & complete charge cycle
recommendations.
Float-Charging: For charging sources that may be charging the battery for an extended
period of time (solar, or an alternator if motoring for a while); set the float voltage to
13.4V or 13.5V for the G31 and 4.5V for the L15. Firefly batteries do not require a float
charge. But, if you are float charging, due to their longer projected lifespan, it is
important to keep the float voltage at 13.4V or 13.5V (4.5V for each 4V/450AH) to ensure
the battery lasts for as many cycles as possible.
Reset to bulk phase: for programmable charging sources, adjust the “reset to bulk
phase” to occur if the battery voltage drops below 12.0V for >1 minute for the G31 or
4.0V for >1 minute for the 4V/450AH.
Periodic Fast & Complete Charge Cycle Recommendations: Note that periodic fast (high
current) charging from a low state of charge can help restore usable capacity after
periods of repeated slow charging (less than 0.2C) or deep discharge cycles. It is
recommended that the battery goes through a complete charge cycle from a low state of
charge every week if they are being heavily cycled or at minimum every 30 days. Ideally
the batteries will be charged at a current of 0.4C (46 Amps for an Oasis G31) but a
minimum of 0.2C (25A per G31 battery) is acceptable. For applications lacking fast
charging capability, contact OPE or for alternative restoration procedures.
Operating Temperature: The optimum operating temperature for a lead-acid battery is
25°C (77°F). As a rule of thumb, every 8-10°C (14-18°F) rise in temperature will cut the
battery life in half. Note that continuous duty at elevated temperature will shorten the
life of any battery. At sub zero ambient at CCCV charging , reduce the limit current to
0.1C Amps instead of 0.4C rate charging for prolonged duration.
Restoration Charge
As stated, Firefly Batteries can operate in a partial state of charge for long periods of time
without sustaining any permanent damage. The usable capacity will decrease, however, with
each cycle within a partial state of charge, up to a point. In order to regain the full original
capacity and in some cases more, it is necessary to perform a restoration charge. To perform the
restoration charge: charge the G31 to 14.4V or the 4V/450AH to 4.8V and continue to charge
until the current drops to 0.5 A on the G31 or 3A on a 4V/450AH. Fully discharge the battery to
10.5V (G31) or 3.5V (4V/450AH), and then repeat the same charge cycle.
Safety
For any operation on the batteries, from storage to recycling, the
following safety rules should be observed:
Do not smoke.
Use tools with insulated handles to tighten connections.
Check that the connections between the cells / monoblocs are fitted
correctly.
