3.5 Watt, 12-Volt Solar Battery Trickle Charger with OBD-II Connector

Trickle charge your vehicle’s 12V battery with the Coleman 3.5W Trickle Charger with OBD-II Connector.


  • Ideal for trickle charging the batteries of cars, SUVs, and trucks
  • Made of durable ABS plastic and shatterproof tempered glass
  • Amorphous solar technology allows the panel to operate in all daylight conditions, even on cloudy days
  • Fully weatherproof design
  • Three easy connection options:
  • (1) OBD-II (On-board diagnostic) connector allows the solar panel to connect to the onboard diagnostics port in most modern vehicles for quick, safe and convenient battery charging
  • (2) Connects to vehicle’s 12V socket with included 12V DC plug
  • (3) Connects directly to battery with included battery clamps
  • Suction cups allow the panel to be mounted inside a vehicle’s windshield


  • Solar panel with 10ft. (3m) of wire
  • OBD-II connector & fuse
  • 12V DC plug
  • Battery clamps
  • Suction cups

Technical Information

  • Power Rating:3.5W
  • Working Voltage:15V
  • Amperage:233 mA
  • Solar Technology: Amorphous


The OBD-II connector allows the solar panel to charge through a vehicle’s On-Board Diagnostic Port. This method of charging is ideal as the OBD-II port is always live.

For safety reasons, the solar panel should be stored while the vehicle is in motion as any distraction to the driver can be dangerous.

No, anything below 15W will not overcharge a standard automobile battery.

No, a solar battery charge controller is only needed for panels of 15 Watts or greater.

A trickle charger is designed to slowly increase a battery’s voltage, offsetting any natural decrease. The actual time to charge a battery is governed more by the size and condition of the battery than the trickle charger.

To measure the voltage of the panel, use a voltmeter. The open-circuit voltage reading should be between 16 and 25 volts in full sun (not connected to the battery).

Yes, panel extensions and panel accessories can be purchased through our order parts page.

Yes, this panel comes with a 5-year limited warranty.