7.4V (2S) Li-ion Charger 8.4V 2A DC 5.5×2.1mm for 18650 21700 Battery Pack

2S 7.4V Li-ion Battery Charger – 8.4V Output (DC 5.5 × 2.1 mm)

This CC/CV charger is designed for 2S (7.4V nominal) lithium-ion battery packs that charge to 8.4V max. Ideal for DIY battery builders, scooters, robotics, audio packs, LED projects, and custom power systems using 18650 or 21700 cells with a 2S BMS.

Key Features

• Output: 8.4V DC (correct full-charge voltage for 2S Li-ion)
• Charging method: CC/CV (constant current / constant voltage)
• Connector: DC 5.5 × 2.1 mm (center positive)
• Compatible with 18650, 21700 and other Li-ion cells in 2S configuration
• US wall plug – 100–240V AC input
• Compact, lightweight, plug-and-play

Compatibility Notes

• For battery packs using a 2S BMS (8.4V maximum charge)
• Works regardless of cell size as long as the pack is configured as 2 cells in series (2S)
• Not compatible with 3S, 4S, LiFePO₄, or non-lithium batteries

What’s Included

• 1 × 2S Li-ion Battery Charger (8.4V output, DC 5.5 × 2.1 mm)

Selected by RenewSpark for DIY battery builders and technicians who need a reliable 2S charger.

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