What is Float Voltage and Charging Voltage?

    What is Float Voltage and Charging Voltage?

    float voltage

    It is the voltage at which a battery is maintained after being fully charged to maintain that capacity by compensating for self-discharge of the battery. The voltage could be kept constant for the entire duration of the cell's operation (such as in a solar battery) or it could be maintained for a particular phase of charging by the charger. The proper float voltage varies significantly with battery chemistry and construction, and with ambient temperature.

    With the proper voltage for the battery type and with proper temperature compensation, a float charger can stay connected indefinitely without damaging the battery.

    charging voltage

    The charging voltage should be between 13,8 and 14,4 V at a temperature between 15 and 25 °C. The optimal value of the charging current should be one tenth of the battery capacity (e.g. 4 A for a 40 Ah battery)

    and for “fast” charges at most a third of the capacity. But the battery should not be charged to the maximum with high currents. A fast charging device can recharge a lead vacuum quickly, but only up to 70%, from then on it should be charged with lower currents to avoid corrosion of the mesh. (e.g. it will automatically change Float charging mode).

    The following Charging Voltage and Floating Voltage of each types of batteries:

    Open Lead Acid

    Hen/Stag Monoblock batteries They are the most economical batteries on the market, they have great performance, very useful for small installations, but taking into account that they do not withstand starting peaks very well and these can reduce their useful life, these batteries have a useful life of 4 or 5 years, the output voltages of monoblock batteries are usually 6V or 12V. These batteries require maintenance approximately every 6 months.

    It has a low cost
    They withstand large specific discharges


    Hen/Stag AGM batteries They are sealed batteries, therefore they are maintenance-free, this is because the electrolyte is absorbed by a fiberglass mesh, they have a good self-discharge rate and can even go for long periods without needing to recharge, they have an approximate useful life 12 years old.

    Typically used for small installations

    Good value for money
    High resistance to depth of discharge
    They do not require maintenance
    Very low self-discharge value
    Great temperature resistance


    Hen/Stag gel batteries They stand out for their great performance and durability, these batteries are sealed, making them safer for isolated installations, since they do not require maintenance either. These batteries have a useful life of approximately 15 years.

    Long duration
    High resistance to depth of discharge
    They do not require maintenance
    Respectful of the environment
    Less self discharge

    Stationary Batteries (OPzS, TOPzS and CPzS)

    These batteries are made up of 2v cells each, which are connected together to be able to have 12v, 24v or 48v systems. These batteries are designed for large installations with a longer duration. They are open batteries, therefore their maintenance must be checked. which will be approximately every 6 months, they usually have a useful life of 17 years. The difference between the OPzS and TOPzS is that TOPzS are made with a translucent material, reducing part of their costs. The batteries CPzS They use a different container than the OPzS, making it have a lower concentration of electrolyte, making its maintenance more frequent.
    They are used for installations that require large powers and energy.

    deep discharge
    Long useful life
    Easy replacement
    Large amount of energy
    Constant Power


    Hen/Stag Lithium batteries They are the ones with the longest useful life on the market, these batteries have a very low self-discharge and an incredible depth of discharge, these batteries do not have very high weights since they are manufactured with the lightest elements possible. These batteries have an approximate useful life of more than 10 years depending on the heat the battery receives (ideally 25ºC). They are used for any type of installation and are the best on the current market.


    They can be charged at any time without affecting their useful life.

    More energy in less space

    More storage

    Longer shelf life

    They do not emit gases or vapors

    Whenever you have any type of query, do not hesitate to contact us through our phone number 854556349 or an e-mail at servicio@wccsolar.es or on our part of contact

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