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Sterling BB122470 battery-to-battery charger front

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  • Sterling BB122470 battery-to-battery charger front
  • Sterling BB122470 battery-to-battery charger
  • Sterling BB122470 battery-to-battery charger with temp sensor
  • Sterling BB122470 battery-to-battery charger side

Sterling Battery-to-Battery Charger | 24V In - 12V Out | 35 Amp Input

SKU: ST-BB241235
Pro Batt Ultra Model # BB241235
Charges 12 volt batteries from a 24 volt system

Availability: In stock

Product Description


    Charges a 12 volt battery from a 24 volt charging system. Capacity is 35A @ 24V input, and approximately 65A @ 12V output.

    Sterling's range of Battery to Battery Chargers (B2Bs) has grown significantly over the past few years in an effort to supplement the ever-growing demand from the commercial vehicle, recreational vehicle, and marine industries. B2Bs have become extremely popular, as they charge batteries quickly to reduce run time and without the need for complex wiring. You can provide the batteries with a fast 4-stage charging profle with a very simple and speedy installation, giving you all the benefits of advanced charging without any of the drawbacks. Simply connect the B2B between the battery being charged and the battery you wish to charge.

    • Charges 12V auxiliary batteries from a standard 24V system
    • Each battery bank receives the correct charge current, depending on its state of charge.
    • The voltage drop induced by a long cable run to a remote or bow-mounted battery is corrected for (these batteries tend to not be fully charged otherwise).
    • Alternator output is maximized, minimizing engine run time for battery charging.
    • Remote batteries are properly maintained and de-sulphated, extending battery life.
    • It is possible to charge batteries when voltages differ from the primary system.

    Sterling BB241235 battery to battery charger features:

    Multiple Activation Modes: Automatic for most non vehicle applications,
    Manual for remote activation.
    Regenerative braking (requiring ignition feed),
    Automatic regenerative braking, requiring no ignition feed.

    Step-up options: Output charging at 12V, 24V, 36V and 48V. Input voltages at 12V and 24V, depending on model. (This is 24V to 12V).

    Current is NOT taken from the input battery and given to the output battery. The B2B uses alternator power to charge the output battery. Manual mode and regenerative braking mode allows you to override this.

    Safety features:
    100% fire proof plastic box.
    No screws to corrode.
    Thermal power reduction.
    Multi stage fan cooling.

    Night Time Setting: Allows the unit to run at half power, minimizing fan noise.

    Boost / Reduce Charging: The B2Bs ensure batteries get the correct charging profile irrespective of high or low input voltages.

    Auto on/off: Charger turns on at 26.6V and turns off at 26.0V and thus will not drain the input battery. Regenerative braking mode allows the input voltage to drop to 24.4V.

    Customizable Profile: Choose your own charging profile on the front panel.

    9 preset battery chemistry options: Including AGM, LiFePO4, Gel, Flooded and sealed lead acid.

    4 stage battery charging: The B2B charges batteries 5-20 times faster than a stand alone alternator.

    Very Simple to install: No Electronic Control Unit (ECU) issues. No complex wiring. No warranty issues. Fully prepared for smart alternators (regenerative braking).

    Remote control optional.

    For more information, see the Sterling Battery to Battery Charger Owner's Manual.

Additional Information

    Additional Information

    Manufacturer Sterling Power
    Data Sheet No
    Product Manual No