Charger QOLTEC 36V–42V 4A for e-bike, DC plug 5.5×2.1 mm

QOLTEC 36V–42V 4A charger is a regulated external power supply designed for recharging e-bike battery packs with nominal voltages in the 36–42 V range. Equipped with a standard 5.5×2.1 mm DC plug, the charger delivers up to 4 A of output current and provides stable voltage regulation to support repeated daily charging cycles for commuting and recreational electric bicycles. The compact housing and integrated cable make it suitable for use at home, in the workshop, or when storing the bike between rides.

Advantages

The charger offers steady current output and voltage regulation to reduce the risk of overcharging and to support the safe restoration of lithium and lead-acid battery packs within the specified voltage range. Its universal 5.5×2.1 mm DC connector fits many e-bike battery sockets or intermediate adapters, while the 4 A maximum current provides a balance between charging speed and battery longevity. The unit's compact design and standard mains connector simplify storage and connection.

Suitable for

• Charging e-bike battery packs with nominal voltage 36 V to 42 V
• Home and workshop battery maintenance and topping up
• Daily commuters and recreational cyclists needing reliable overnight charging
• Use with battery systems compatible with a 5.5×2.1 mm DC plug

Key specifications

• Input: standard AC mains voltage (country dependant)
• Output voltage range: suitable for nominal 36 V–42 V battery packs
• Maximum output current: 4 A
• Output connector: 5.5×2.1 mm DC plug
• Regulated output for consistent charging
• Enclosure: compact external power supply design

How to use

Connect the charger to the AC mains using the appropriate country mains lead, then plug the 5.5×2.1 mm DC connector into the compatible socket on the e-bike battery or its external charging port. Ensure the battery nominal voltage falls within the 36–42 V range before beginning charge. Monitor the battery and charger during initial use to confirm correct connection and charging behavior. After the battery reaches the manufacturer-recommended charge level, disconnect the charger first from the battery and then from the mains.

Usage recommendations

Use the charger only with batteries rated for 36–42 V and compatible with a 5.5×2.1 mm DC input. Avoid exposing the charger to moisture, extreme temperatures, or direct sunlight during operation. For longest battery life, follow the battery manufacturer's charging instructions and avoid prolonged storage at full charge.